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Sample records for noise influencing human

  1. Quantum noise influencing human behaviour could fake effectiveness of drugs in clinical trials

    CERN Document Server

    Janzing, D; Janzing, Dominik; Beth, Thomas

    2002-01-01

    To test the effectiveness of a drug one can advice two randomly selected groups of patients to take or not to take it, respectively. It is well-known that the causal effect cannot be identified if not all patients comply. This holds even when the non-compliers can be identified afterwards since latent factors like patient's personality can influence both his decision and his physical response. However, one can still give bounds on the effectiveness of the drug depending on the rate of compliance. Remarkably, the proofs of these bounds given in the literature rely on models that represent all relevant latent factors (including noise) by hidden classical variables. In strong analogy to the violation of Bell's inequality, some of these bounds fail if patient's behavior is influenced by latent quantum processes (e.g. in his nervous system). Quantum effects could fake an increase of the recovery rate by about 13% although the drug would hurt as many patients as it would help if everyone took it. The other bounds a...

  2. The effect of human activity noise on the acoustic quality in open plan office

    DEFF Research Database (Denmark)

    Dehlbæk, Tania Stenholt; Jeong, Cheol-Ho; Brunskog, Jonas

    2016-01-01

    A disadvantage of open plan offices is the noise annoyance. Noise problems in open plan offices have been dealt with in several studies, and standards have been set up. Still, what has not been taken into account is the effect of human activity noise on acoustic conditions. In this study, measure...... D2,S have an impact on the variation in the activity noise. At 1 kHz, the technical background noise influences human activity noise positively. In both octave bands, the human activity noise level varies significantly with the office type, from a call center to a lawyer’s office....

  3. Environmental noise and human prenatal growth

    Energy Technology Data Exchange (ETDEWEB)

    Schell, L.M.

    1981-09-01

    To determine whether chronic exposure to relatively loud noise has demonstrable biological effects in humans, a study was conducted on the effect of mother's exposure to airport noise while pregnant, and of social and biological characteristics of the family upon birthweight and gestation length. The sample of births was drawn from a community located adjacent to an international airport in the U.S., where noise levels had been measured previously. Mother's noise exposure was based upon noise levels near her residence in the community while she was pregnant. Data from 115 births were used, these being from mothers whose noise exposure history was most complete throughout the pregnancy. Using multivariate analysis to correct for family characteristics, the partial correlation coefficient for noise exposure and gestation length was negative, large, and significant in girls (r . -0.49, p less than 0.001). In boys the partial correlation coefficient was also negative but was smaller and did not quite reach statistical significance. Partial correlations with birthweight were smaller in both boys and girls and not significant. These results agree best with previous studies that suggest that noise may reduce prenatal growth. The size of the observed effects may be related to a conservative research design biased towards underestimation, as well as to the real effects of noise upon human prenatal growth.

  4. Human influences

    NARCIS (Netherlands)

    Lanen, van H.A.J.; Kasparek, L.; Novicky, O.; Querner, E.P.; Fendeková, M.; Kupczyk, E.

    2004-01-01

    Human activities can cause drought, which was not previously reported (man-induced hydrological drought). Groundwater abstractions for domestic and industrial use are a well-known example of such an environmental change

  5. Tram squealing noise and its impact on human health

    Directory of Open Access Journals (Sweden)

    Eva Panulinova

    2016-01-01

    Full Text Available Introduction: Tramway has become a serious urban noise source in densely populated areas. The disturbance from squealing noise is significant. Curve squeal is the very loud, tonal noise emitted by tram operation in tight radius curves. Studies had reported a relationship between noise levels and health effects, such as annoyance, sleep disturbance, and elevated systolic and diastolic blood pressure. Materials and Methods: This study aimed to analyze the wheel squeal noise along the tramway line in Košice, Slovakia, review the effects on human health, and discuss its inclusion in the design method. To observe the influence of a track curve on noise emission, several measurement points were selected, and the noise emission was measured both in the curve and in the straight lines employing the same type of permanent way. Results: The results in the sections with the radius below 50 m were greatly affected by the presence of a squeal noise, while the resulting noise level in the sections with the radius above 50 m depended on their radius. The difference between the average values of LAeq with and without the squeal in the measurement points with the radius below 50 m was 9 dB. The difference between the measurements in the curve sections with the radius below 50 m and those in the straight line was 2.7 dB. Conclusion: The resulting noise level in general was influenced by the car velocity and the technical shape of the permanent way. These results can be used in noise prognoses and in the health effect predictions.

  6. Phase Noise Influence in Optical OFDM Systems employing RF Pilot Tone for Phase Noise Cancellation

    OpenAIRE

    Jacobsen, Gunnar; Kazovsky, Leonid G.; Xu, TianHua; Popov, Sergei; Li, Jie; Zhang, Yimo; Friberg, Ari T.

    2016-01-01

    For coherent and direct-detection Orthogonal Frequency Division Multiplexed (OFDM) systems employing radio frequency (RF) pilot tone phase noise cancellation the influence of laser phase noise is evaluated. Novel analytical results for the common phase error and for the (modulation dependent) inter carrier interference are evaluated based upon Gaussian statistics for the laser phase noise. In the evaluation it is accounted for that the laser phase noise is filtered in the correlation signal d...

  7. Noise Effects on Human Performance: A Meta-Analytic Synthesis

    Science.gov (United States)

    Szalma, James L.; Hancock, Peter A.

    2011-01-01

    Noise is a pervasive and influential source of stress. Whether through the acute effects of impulse noise or the chronic influence of prolonged exposure, the challenge of noise confronts many who must accomplish vital performance duties in its presence. Although noise has diffuse effects, which are shared in common with many other chronic forms of…

  8. Influence of microparticle size on cavitation noise during ultrasonic vibration

    Directory of Open Access Journals (Sweden)

    H. Ge

    2015-09-01

    Full Text Available The cavitation noise in the ultrasonic vibration system was found to be influenced by the size of microparticles added in water. The SiO2 microparticles with the diameter smaller than 100 μm reduced the cavitation noise, and the reason was attributed to the constrained oscillation of the cavitation bubbles, which were stabilized by the microparticles.

  9. 1/f Noise Outperforms White Noise in Sensitizing Baroreflex Function in the Human Brain

    Science.gov (United States)

    Soma, Rika; Nozaki, Daichi; Kwak, Shin; Yamamoto, Yoshiharu

    2003-08-01

    We show that externally added 1/f noise more effectively sensitizes the baroreflex centers in the human brain than white noise. We examined the compensatory heart rate response to a weak periodic signal introduced via venous blood pressure receptors while adding 1/f or white noise with the same variance to the brain stem through bilateral cutaneous stimulation of the vestibular afferents. In both cases, this noisy galvanic vestibular stimulation optimized covariance between the weak input signals and the heart rate responses. However, the optimal level with 1/f noise was significantly lower than with white noise, suggesting a functional benefit of 1/f noise for neuronal information transfer in the brain.

  10. Influence of environmental noise on the weak value amplification

    Science.gov (United States)

    Zhu, Xuannmin; Zhang, Yu-Xiang

    2016-08-01

    Quantum systems are always disturbed by environmental noise. We have investigated the influence of the environmental noise on the amplification in weak measurements. Three typical quantum noise processes are discussed in this article. The maximum expectation values of the observables of the measuring device decrease sharply with the strength of the depolarizing and phase damping channels, while the amplification effect of weak measurement is immune to the amplitude damping noise. To obtain significantly amplified signals, we must ensure that the preselection quantum systems are kept away from the depolarizing and phase damping processes.

  11. Detection of microbiologically influenced corrosion by electrochemical noise transients

    NARCIS (Netherlands)

    Homborg, A.M.; Morales, C.F. Leon; Tinga, Tiedo; de Wit, J.H.W.; Mol, J.M.C.

    2014-01-01

    This work investigates the electrochemical processes involved in pitting corrosion induced by microbiologically influenced corrosion by using time-resolved instantaneous frequency information of electrochemical current noise (ECN) transients obtained from Hilbert spectra. In addition to the

  12. Influence of refraction on wind turbine noise

    CERN Document Server

    Makarewicz, Rufin

    2013-01-01

    A semi-empirical method is applied to calculate the time-average sound level of wind turbine noise generation and propagation. Both are affected by wind shear refraction. Under upwind conditions the partially ensonified zone separates the fully ensonified zone (close to the turbine) and the shadow zone (far away from the turbine). Refraction is described in terms of the wind speed linear profile fitted to the power law profile. The rotating blades are treated as a two-dimensional circular source in the vertical plane. Inside the partially ensonified zone the effective A-weighted sound power decreases to zero when the receiver moves from the turbine toward the shadow zone. The presented results would be useful in practical applications to give a quick estimate of the effect of refraction on wind turbine noise.

  13. Influence of vane sweep on rotor-stator interaction noise

    Science.gov (United States)

    Envia, Edmane; Kerschen, Edward J.

    1990-01-01

    The influence of vane sweep in rotor-stator interaction noise is investigated. In an analytical approach, the interaction of a convected gust representing the rotor viscous wake, with a cascade of cascade of finite span swept airfoils, representing the stator, is analyzed. The analysis is based on the solution of the exact linearized equations of motion. High frequency convected gusts for which noise generation is concentrated near the leading edge of airfoils is considered. In a preliminary study, the problem of an isolated finite span swept airfoil interacting with a convected gust is analyzed. Results indicate that sweep can substantially reduce the farfield noise levels for a single airfoil. Using the single airfoil model, an approximate solution to the problem of noise radiation from a cascade of finite span swept airfoils interacting with a convected gust is derived. A parametric study of noise generated by gust cascade interaction is carried out to assess the effectiveness of vane sweep in reducing rotor-stator interaction noise. The results show that sweep is beneficial in reducing noise levels. Rotor wake twist or circumferential lean substantially influences the effectiveness of vane sweep. The orientation of vane sweep must be chosen to enhance the natural phase lag caused by wake lean, in which case rather small sweep angles substantially reduce the noise levels.

  14. The influence of road traffic noise on sleep

    Science.gov (United States)

    Eberhardt, J. L.

    1988-12-01

    The influence of road traffic noise on the sleep of adults and 6-11 year old children was studied by using electrophysiological methods. Young adults, unaccustomed to traffic noise, were disturbed by continuous and intermittent traffic noise at 45 dB(A). No sleep disturbances were found for continuous traffic noise at 36 dB(A). Car passages with a peak noise level of 55 dB(A) caused awakenings. The equivalent sound pressure level ( Leq) did not correlate with sleep disturbance effects. A better noise dose description was found in the number of vehicles per night that made most noise. Children wer about 10 dB(A) less sensitive than adults to awakening reactions, and even less sensitive with respect to disturbances of REM sleep and deep sleep. Total habituation to road traffic noise did not occur, even after at least one year of exposure. Sound reduction in the bedroom induced increased amounts of deep sleep for adults and reduced falling-asleep time for children. Road traffic noise during the first hours of a night's sleep tended to disturb sleep more than when it ocurred later in the night, the main effects being a reduction of the total amount of REM sleep during the night and an increased duration of intermittent wakefulness during the hours of exposure.

  15. The possible influence of noise frequency components on the health of exposed industrial workers - A review

    Directory of Open Access Journals (Sweden)

    K V Mahendra Prashanth

    2011-01-01

    Full Text Available Noise is a common occupational health hazard in most industrial settings. An assessment of noise and its adverse health effects based on noise intensity is inadequate. For an efficient evaluation of noise effects, frequency spectrum analysis should also be included. This paper aims to substantiate the importance of studying the contribution of noise frequencies in evaluating health effects and their association with physiological behavior within human body. Additionally, a review of studies published between 1988 and 2009 that investigate the impact of industrial/occupational noise on auditory and non-auditory effects and the probable association and contribution of noise frequency components to these effects is presented. The relevant studies in English were identified in Medknow, Medline, Wiley, Elsevier, and Springer publications. Data were extracted from the studies that fulfilled the following criteria: title and/or abstract of the given study that involved industrial/occupational noise exposure in relation to auditory and non-auditory effects or health effects. Significant data on the study characteristics, including noise frequency characteristics, for assessment were considered in the study. It is demonstrated that only a few studies have considered the frequency contributions in their investigations to study auditory effects and not non-auditory effects. The data suggest that significant adverse health effects due to industrial noise include auditory and heart-related problems. The study provides a strong evidence for the claims that noise with a major frequency characteristic of around 4 kHz has auditory effects and being deficient in data fails to show any influence of noise frequency components on non-auditory effects. Furthermore, specific noise levels and frequencies predicting the corresponding health impacts have not yet been validated. There is a need for advance research to clarify the importance of the dominant noise frequency

  16. Masking of Wind Turbine Noise: Influence of wind turbulence on ambient noise fluctuations

    Energy Technology Data Exchange (ETDEWEB)

    Fegeant, Olivier

    2002-07-01

    In the issue of noise annoyance generated by wind turbines, masking by ambient noise is of great importance. At wind turbine sites, the main source of ambient noise arises from the wind blowing on the vegetation. However, natural wind can barely be described as a steady flow and 'lulls' and 'gusts' are words used to describe its unsteady component. This latter, also called wind turbulence, may affect the masking effect, as the wind turbine may become audible during short laps of time of low wind speed, that is of low ambient noise. The aim of the present report is to study the influence of wind turbulence on ambient noise fluctuations. It is shown that these latter are governed not only by the turbulence intensity, but also by its temporal and spatial structure. This report provides some elements of atmospheric turbulence as well as techniques for the simulation of turbulent wind fields. Simulation results are given that illustrate how the standard deviation of the vegetation noise can vary as function of the canopy size and turbulence spatial patterns. Finally, ambient noise fluctuations and their statistical descriptions are also discussed, based on both theoretical considerations and empirical results.

  17. Considering the influence of artificial environmental noise to study cough time-frequency features

    Science.gov (United States)

    Van Hirtum, A.; Berckmans, D.

    2003-09-01

    In general the study of the cough mechanism and sound in both animal and human is performed by eliciting coughing in a reproducible way by nebulization of an irritating substance. Due to ventilation the controlled evaporation-protocol causes artificial noises from a mechanical origin. The resulting environmental low-frequency noises complicate cough time-frequency features. In order to optimize the study of the cough-sound the research described in this paper attempts on the one hand to characterize and model the environmental noises and on the other hand to evaluate the influence of the noise on the time-frequency representation for the intended cough sounds by comparing different de-noising approaches. Free field acoustic sound is continuously registered during 30 min citric acid cough-challenges on individual Belgian Landrace piglets and during respiratory infection experiments, with a duration of about 10 days, where room-ventilation was present.

  18. Phase Noise Influence in Optical OFDM Systems employing RF Pilot Tone for Phase Noise Cancellation

    Science.gov (United States)

    Jacobsen, Gunnar; Kazovsky, Leonid G.; Xu, Tianhua; Popov, Sergei; Li, Jie; Zhang, Yima; Friberg, Ari T.

    2011-06-01

    For coherent and direct-detection Orthogonal Frequency Division Multiplexed (OFDM) systems employing radio frequency (RF) pilot tone phase noise cancellation the influence of laser phase noise is evaluated. Novel analytical results for the common phase error and for the (modulation dependent) inter carrier interference are evaluated based upon Gaussian statistics for the laser phase noise. In the evaluation it is accounted for that the laser phase noise is filtered in the correlation signal detection. Numerical results are presented for OFDM systems with 4 and 16 PSK modulation, 200 OFDM bins and baud rate of 1 GS/s. It is found that about 225 km transmission is feasible for the coherent 4PSK-OFDM system over normal (G.652) fiber.

  19. Phase Noise Influence in Optical OFDM Systems employing RF Pilot Tone for Phase Noise Cancellation

    CERN Document Server

    Jacobsen, Gunnar; Xu, Tianhua; Popov, Sergei; Li, Jie; Zhang, Yimo; Friberg, Ari T

    2016-01-01

    For coherent and direct-detection Orthogonal Frequency Division Multiplexed (OFDM) systems employing radio frequency (RF) pilot tone phase noise cancellation the influence of laser phase noise is evaluated. Novel analytical results for the common phase error and for the (modulation dependent) inter carrier interference are evaluated based upon Gaussian statistics for the laser phase noise. In the evaluation it is accounted for that the laser phase noise is filtered in the correlation signal detection. Numerical results are presented for OFDM systems with 4 and 16 PSK modulation, 200 OFDM bins and baud rate of 1 GS/s. It is found that about 225 km transmission is feasible for the coherent 4PSK-OFDM system over normal (G.652) fiber.

  20. On the influence of freight trains on humans: a laboratory investigation of the impact of nocturnal low frequency vibration and noise on sleep and heart rate.

    Directory of Open Access Journals (Sweden)

    Michael G Smith

    Full Text Available BACKGROUND: A substantial increase in transportation of goods on railway may be hindered by public fear of increased vibration and noise leading to annoyance and sleep disturbance. As the majority of freight trains run during night time, the impact upon sleep is expected to be the most serious adverse effect. The impact of nocturnal vibration on sleep is an area currently lacking in knowledge. We experimentally investigated sleep disturbance with the aim to ascertain the impact of increasing vibration amplitude. METHODOLOGY/PRINCIPAL FINDINGS: The impacts of various amplitudes of horizontal vibrations on sleep disturbance and heart rate were investigated in a laboratory study. Cardiac accelerations were assessed using a combination of polysomnography and ECG recordings. Sleep was assessed subjectively using questionnaires. Twelve young, healthy subjects slept for six nights in the sleep laboratory, with one habituation night, one control night and four nights with a variation of vibration exposures whilst maintaining the same noise exposure. With increasing vibration amplitude, we found a decrease in latency and increase in amplitude of heart rate as well as a reduction in sleep quality and increase in sleep disturbance. CONCLUSIONS/SIGNIFICANCE: We concluded that nocturnal vibration has a negative impact on sleep and that the impact increases with greater vibration amplitude. Sleep disturbance has short- and long-term health consequences. Therefore, it is necessary to define levels that protect residents against sleep disruptive vibrations that may arise from night time railway freight traffic.

  1. The relative importance of noise level and number of events on human reactions to noise: Community survey findings and study methods

    Science.gov (United States)

    Fields, J. M.

    1980-01-01

    The data from seven surveys of community response to environmental noise are reanalyzed to assess the relative influence of peak noise levels and the numbers of noise events on human response. The surveys do not agree on the value of the tradeoff between the effects of noise level and numbers of events. The value of the tradeoff cannot be confidently specified in any survey because the tradeoff estimate may have a large standard error of estimate and because the tradeoff estimate may be seriously biased by unknown noise measurement errors. Some evidence suggests a decrease in annoyance with very high numbers of noise events but this evidence is not strong enough to lead to the rejection of the conventionally accepted assumption that annoyance is related to a log transformation of the number of noise events.

  2. Signs of noise-induced neural degeneration in humans

    DEFF Research Database (Denmark)

    Holtegaard, Pernille; Olsen, Steen Østergaard

    2015-01-01

    Animal studies demonstrated that noise exposure causes a primary and selective loss of auditory-nerve fibres with low spontaneous firing rate. This neuronal impairment, if also present in humans, can be assumed to affect the processing of supra-threshold stimuli, especially in the presence...... thresholds within the “normal” range perform poorer, in terms of their speech recognition threshold in noise (SRTN), and (2) if auditory brainstem responses (ABR) reveal lower amplitude of wave I in the noise-exposed listeners. A test group of noise/music-exposed individuals and a control group were...

  3. Influence of mechanical noise inside a scanning electron microscope.

    Science.gov (United States)

    de Faria, Marcelo Gaudenzi; Haddab, Yassine; Le Gorrec, Yann; Lutz, Philippe

    2015-04-01

    The scanning electron microscope is becoming a popular tool to perform tasks that require positioning, manipulation, characterization, and assembly of micro-components. However, some of these applications require a higher level of performance with respect to dynamics and precision of positioning. One limiting factor is the presence of unidentified noises and disturbances. This work aims to study the influence of mechanical disturbances generated by the environment and by the microscope, identifying how these can affect elements in the vacuum chamber. To achieve this objective, a dedicated setup, including a high-resolution vibrometer, was built inside the microscope. This work led to the identification and quantification of main disturbances and noise sources acting on a scanning electron microscope. Furthermore, the effects of external acoustic excitations were analysed. Potential applications of these results include noise compensation and real-time control for high accuracy tasks.

  4. Statistical mechanics of influence maximization with thermal noise

    Science.gov (United States)

    Lynn, Christopher W.; Lee, Daniel D.

    2017-03-01

    The problem of optimally distributing a budget of influence among individuals in a social network, known as influence maximization, has typically been studied in the context of contagion models and deterministic processes, which fail to capture stochastic interactions inherent in real-world settings. Here, we show that by introducing thermal noise into influence models, the dynamics exactly resemble spins in a heterogeneous Ising system. In this way, influence maximization in the presence of thermal noise has a natural physical interpretation as maximizing the magnetization of an Ising system given a budget of external magnetic field. Using this statistical mechanical formulation, we demonstrate analytically that for small external-field budgets, the optimal influence solutions exhibit a highly non-trivial temperature dependence, focusing on high-degree hub nodes at high temperatures and on easily influenced peripheral nodes at low temperatures. For the general problem, we present a projected gradient ascent algorithm that uses the magnetic susceptibility to calculate locally optimal external-field distributions. We apply our algorithm to synthetic and real-world networks, demonstrating that our analytic results generalize qualitatively. Our work establishes a fruitful connection with statistical mechanics and demonstrates that influence maximization depends crucially on the temperature of the system, a fact that has not been appreciated by existing research.

  5. Noise-induced transition in human reaction times

    Science.gov (United States)

    Medina, José M.; Díaz, José A.

    2016-09-01

    The human reaction/response time can be defined as the time elapsed from the onset of stimulus presentation until a response occurs in many sensory and cognitive processes. A reaction time model based on Piéron’s law is investigated. The model shows a noise-induced transition in the moments of reaction time distributions due to the presence of strong additive noise. The model also demonstrates that reaction times do not follow fluctuation scaling between the mean and the variance but follow a generalized version between the skewness and the kurtosis. The results indicate that noise-induced transitions in the moments govern fluctuations in sensory-motor transformations and open an insight into the macroscopic effects of noise in human perception and action. The conditions that lead to extreme reaction times are discussed based on the transfer of information in neurons.

  6. Influence of Spanwise Boundary Conditions on Slat Noise Simulations

    Science.gov (United States)

    Lockard, David P.; Choudhari, Meelan M.; Buning, Pieter G.

    2015-01-01

    The slat noise from the 30P/30N high-lift system is being investigated through computational fluid dynamics simulations with the OVERFLOW code in conjunction with a Ffowcs Williams-Hawkings acoustics solver. In the present study, two different spanwise grids are being used to investigate the effect of the spanwise extent and periodicity on the near-field unsteady structures and radiated noise. The baseline grid with periodic boundary conditions has a short span equal to 1/9th of the stowed chord, whereas the other, longer span grid adds stretched grids on both sides of the core, baseline grid to allow inviscid surface boundary conditions at both ends. The results indicate that the near-field mean statistics obtained using the two grids are similar to each other, as are the directivity and spectral shapes of the radiated noise. However, periodicity forces all acoustic waves with less than one wavelength across the span to be two-dimensional, without any variation in the span. The spanwise coherence of the acoustic waves is what is needed to make estimates of the noise that would be radiated from realistic span lengths. Simulations with periodic conditions need spans of at least six slat chords to allow spanwise variation in the low-frequencies associated with the peak of broadband slat noise. Even then, the full influence of the periodicity is unclear, so employing grids with a fine, central region and highly stretched meshes that go to slip walls may be a more efficient means of capturing the spanwise decorrelation of low-frequency acoustic phenomena.

  7. Guide to the evaluation of human exposure to noise from large wind turbines

    Science.gov (United States)

    Stephens, D. G.; Shepherd, K. P.; Hubbard, H. H.; Grosveld, F.

    1982-01-01

    Guidance for evaluating human exposure to wind turbine noise is provided and includes consideration of the source characteristics, the propagation to the receiver location, and the exposure of the receiver to the noise. The criteria for evaluation of human exposure are based on comparisons of the noise at the receiver location with the human perception thresholds for wind turbine noise and noise-induced building vibrations in the presence of background noise.

  8. Toward Reduced Aircraft Community Noise Impact Via a Perception-Influenced Design Approach

    Science.gov (United States)

    Rizzi, Stephen A.

    2016-01-01

    This is an exciting time for aircraft design. New configurations, including small multi-rotor uncrewed aerial systems, fixed- and tilt-wing distributed electric propulsion aircraft, high-speed rotorcraft, hybrid-electric commercial transports, and low-boom supersonic transports, are being made possible through a host of propulsion and airframe technology developments. The resulting noise signatures may be radically different, both spectrally and temporally, than those of the current fleet. Noise certification metrics currently used in aircraft design do not necessarily reflect these characteristics and therefore may not correlate well with human response. Further, as operations and missions become less airport-centric, e.g., those associated with on-demand mobility or package delivery, vehicles may operate in closer proximity to the population than ever before. Fortunately, a new set of tools are available for assessing human perception during the design process in order to affect the final design in a positive manner. The tool chain utilizes system noise prediction methods coupled with auralization and psychoacoustic testing, making possible the inclusion of human response to noise, along with performance criteria and certification requirements, into the aircraft design process. Several case studies are considered to illustrate how this approach could be used to influence the design of future aircraft.

  9. Influence of background noise on the performance in the odor sensitivity task: effects of noise type and extraversion.

    Science.gov (United States)

    Seo, Han-Seok; Hähner, Antje; Gudziol, Volker; Scheibe, Mandy; Hummel, Thomas

    2012-10-01

    Recent research demonstrated that background noise relative to silence impaired subjects' performance in a cognitively driven odor discrimination test. The current study aimed to investigate whether the background noise can also modulate performance in an odor sensitivity task that is less cognitively loaded. Previous studies have shown that the effect of background noise on task performance can be different in relation to degree of extraversion and/or type of noise. Accordingly, we wanted to examine whether the influence of background noise on the odor sensitivity task can be altered as a function of the type of background noise (i.e., nonverbal vs. verbal noise) and the degree of extraversion (i.e., introvert vs. extrovert group). Subjects were asked to conduct an odor sensitivity task in the presence of either nonverbal noise (e.g., party sound) or verbal noise (e.g., audio book), or silence. Overall, the subjects' mean performance in the odor sensitivity task was not significantly different across three auditory conditions. However, with regard to the odor sensitivity task, a significant interaction emerged between the type of background noise and the degree of extraversion. Specifically, verbal noise relative to silence significantly impaired or improved the performance of the odor sensitivity task in the introvert or extrovert group, respectively; the differential effect of introversion/extraversion was not observed in the nonverbal noise-induced task performance. In conclusion, our findings provide new empirical evidence that type of background noise and degree of extraversion play an important role in modulating the effect of background noise on subjects' performance in an odor sensitivity task.

  10. The possible influence of noise frequency components on the health of exposed industrial workers--a review.

    Science.gov (United States)

    Mahendra Prashanth, K V; Venugopalachar, Sridhar

    2011-01-01

    Noise is a common occupational health hazard in most industrial settings. An assessment of noise and its adverse health effects based on noise intensity is inadequate. For an efficient evaluation of noise effects, frequency spectrum analysis should also be included. This paper aims to substantiate the importance of studying the contribution of noise frequencies in evaluating health effects and their association with physiological behavior within human body. Additionally, a review of studies published between 1988 and 2009 that investigate the impact of industrial/occupational noise on auditory and non-auditory effects and the probable association and contribution of noise frequency components to these effects is presented. The relevant studies in English were identified in Medknow, Medline, Wiley, Elsevier, and Springer publications. Data were extracted from the studies that fulfilled the following criteria: title and/or abstract of the given study that involved industrial/occupational noise exposure in relation to auditory and non-auditory effects or health effects. Significant data on the study characteristics, including noise frequency characteristics, for assessment were considered in the study. It is demonstrated that only a few studies have considered the frequency contributions in their investigations to study auditory effects and not non-auditory effects. The data suggest that significant adverse health effects due to industrial noise include auditory and heart-related problems. The study provides a strong evidence for the claims that noise with a major frequency characteristic of around 4 kHz has auditory effects and being deficient in data fails to show any influence of noise frequency components on non-auditory effects. Furthermore, specific noise levels and frequencies predicting the corresponding health impacts have not yet been validated. There is a need for advance research to clarify the importance of the dominant noise frequency contribution in

  11. Noise

    Science.gov (United States)

    Noise is all around you, from televisions and radios to lawn mowers and washing machines. Normally, you ... sensitive structures of the inner ear and cause noise-induced hearing loss. More than 30 million Americans ...

  12. The influences of low frequency noise on mental performance

    Directory of Open Access Journals (Sweden)

    J. Hatami

    2008-01-01

    Full Text Available AbstractBackground and Purpose: Although the evolution of industrial systems toward digital technologies decreased the exposure to high levels of noise, it has created some problems encountered with low level and provoking noise (low frequency noise. In the present work, the mental performance of students exposed to low frequency and reference noises at low and high levels (45 & 65 dB were studied. Additionally, other factors such as annoyance, sensitivity to low frequency noise and hearing status of participants were considered.Materials and Methods: After generating low frequency and reference noises required for the study, a pilot study was conducted. Then, 54 students participated in the main study after preliminary tests. Their mental performances were evaluated with standard psychological tests while they were exposed to low frequency and reference noises at 45 and 65 dBA.Results: The results showed that noise annoyance and low frequency noise sensitivity do not have a significant correlation with age and sex. The results also revealed that, low frequency noise at 65 dB can decrease concentration (P=0.003 and increase response time (P=0.039 of performance in comparison with low frequency noise at 45 dB. On the other hand, reference noise at 65 dB can increase speed (P<0.001 of performance in comparison with reference noise at 45 dB.Conclusion: Low frequency noise can reduce the mental performance and increase its response time.Key words: Low Frequency Noise, Reference Noise, Noise Annoyance, Mental PerformanceJ Mazand Univ Med Sci 2008; 18(63: 55-65(Persian

  13. Beam-beam effects under the influence of external noise

    CERN Document Server

    Ohmi, K.

    2014-01-01

    Fast external noise, which gives fluctuation into the beam orbit, is discussed in connection with beam-beam effects. Phase noise from crab cavities and detection devices (position monitor) and kicker noise from the bunch by bunch feedback system are the sources. Beam-beam collisions with fast orbit fluctuations with turn by turn or multi-turn correlations, cause emittance growth and luminosity degradation. We discuss the tolerance of the noise amplitude for LHC and HL-LHC.

  14. Quantification of airport community noise impact in terms of noise levels, population density, and human subjective response

    Science.gov (United States)

    Deloach, R.

    1981-01-01

    The Fraction Impact Method (FIM), developed by the National Research Council (NRC) for assessing the amount and physiological effect of noise, is described. Here, the number of people exposed to a given level of noise is multiplied by a weighting factor that depends on noise level. It is pointed out that the Aircraft-noise Levels and Annoyance MOdel (ALAMO), recently developed at NASA Langley Research Center, can perform the NRC fractional impact calculations for given modes of operation at any U.S. airport. The sensitivity of these calculations to errors in estimates of population, noise level, and human subjective response is discussed. It is found that a change in source noise causes a substantially smaller change in contour area than would be predicted simply on the basis of inverse square law considerations. Another finding is that the impact calculations are generally less sensitive to source noise errors than to systematic errors in population or subjective response.

  15. Reduction of noise influence during the periodical inspection of the nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Hikono, Masaru [Inst. of Nuclear Safety System Inc., Mihama, Fukui (Japan)

    2002-09-01

    At the nuclear power plant under the regular inspection, the sound level and the worker's impression of the environmental noises were measured. The environmental noise was the level with a possibility to cause the noise-induced deafness and have the psychological influence on the workers such as ''Get irritated''. These results imply the necessity of the noise countermeasure. For the noise influence relaxation, we examined the effectiveness of ear protections (e.g., ear plugs) and the intelligibility improvement of the paging system, prepared the noise management manual and the educational leaflet for the support of worker's self-defense. The results of the examinations showed that ear plug was effective especially in the high-noise environment and that the improvement of paging system increased the intelligibility. (author)

  16. The influence of the noise environment on crew communications

    Science.gov (United States)

    Leverton, J. W.

    1978-01-01

    The noise environment and how it affects crew communications in helicopters is considered. The signal to noise (S/N) ratio at the microphone and the effect of the attenuation provided by the helmet is discussed. This shows that the most important aspect is the S/N ratio at the microphone, particularly when helmets with improved attenuation characteristics are considered. Evidence is presented which shows that in high noise environments, the system S/N ratio is well below that required and hence there is an urgent need to reduce the cabin noise levels and improve the microphone rejection properties. Emphasis is placed on environmental/acoustic considerations.

  17. Unexpected arousal modulates the influence of sensory noise on confidence

    Science.gov (United States)

    Allen, Micah; Frank, Darya; Schwarzkopf, D Samuel; Fardo, Francesca; Winston, Joel S; Hauser, Tobias U; Rees, Geraint

    2016-01-01

    Human perception is invariably accompanied by a graded feeling of confidence that guides metacognitive awareness and decision-making. It is often assumed that this arises solely from the feed-forward encoding of the strength or precision of sensory inputs. In contrast, interoceptive inference models suggest that confidence reflects a weighted integration of sensory precision and expectations about internal states, such as arousal. Here we test this hypothesis using a novel psychophysical paradigm, in which unseen disgust-cues induced unexpected, unconscious arousal just before participants discriminated motion signals of variable precision. Across measures of perceptual bias, uncertainty, and physiological arousal we found that arousing disgust cues modulated the encoding of sensory noise. Furthermore, the degree to which trial-by-trial pupil fluctuations encoded this nonlinear interaction correlated with trial level confidence. Our results suggest that unexpected arousal regulates perceptual precision, such that subjective confidence reflects the integration of both external sensory and internal, embodied states. DOI: http://dx.doi.org/10.7554/eLife.18103.001 PMID:27776633

  18. Noise peaks influence communication in the operating room. An observational study.

    Science.gov (United States)

    Keller, Sandra; Tschan, Franziska; Beldi, Guido; Kurmann, Anita; Candinas, Daniel; Semmer, Norbert K

    2016-12-01

    Noise peaks are powerful distractors. This study focuses on the impact of noise peaks on surgical teams' communication during 109 long abdominal surgeries. We related measured noise peaks during 5-min intervals to the amount of observed communication during the same interval. Results show that noise peaks are associated with less case-relevant communication; this effect is moderated by the level of surgical experience; case-relevant communications decrease under high noise peak conditions among junior, but not among senior surgeons. However, case-irrelevant communication did not decrease under high noise level conditions, rather there was a trend to more case-irrelevant communication under high noise peaks. The results support the hypothesis that noise peaks impair communication because they draw on attentional resources rather than impairing understanding of communication. As case-relevant communication is important for surgical performance, exposure to high noise peaks in the OR should be minimised especially for less experienced surgeons. Practitioner Summary: This study investigated whether noise during surgeries influenced the communication within surgical teams. During abdominal surgeries, noise levels were measured and communication was observed. Results showed that high noise peaks reduced the frequency of patient-related communication, but did not reduce patient-irrelevant communication. Noise may negatively affect team coordination in surgeries.

  19. Running train induced vibrations and noises of elevated railway structures and their influences on environment

    Institute of Scientific and Technical Information of China (English)

    He XIA; Fei GAO; Xuan WU; Nan ZHANG; Guido DE ROECK; Geert DEGRANDE

    2009-01-01

    The vibrations and noises of elevated railway structures have been cause for concern due to their effects on the environment and the people living near elevated lines. In this paper, the main structural features of some new elevated bridges and station hall were introduced. The generation mechanism of vibrations and noise of elevated structures induced by trains were investigated. The noise induced by different types of elevated bridges, their influences on the environment and the theoretical method for the analysis of structure borne noise was analyzed.Finally, several field measurements on train induced noises at the platforms of elevated subway stations and bridges were presented.

  20. Influence of Noise on Time Evolution of Intensity Correlation Function

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Using the linear approximation method, we have studied how the correlation function C(t) of the laser intensity changes with time in the loss-noise model of the single-mode laser driven by the colored pump noise with signal modulation and the quantum noise with cross-correlation between the real and imaginary parts. We have found that when the pump noise self-correlation time τ changes, (I) in the case ofτ 1, the curve only exhibits periodically surging with descending envelope. When τ < 1 and τ does not change, with the increase of the pump noise intensity P, the curve experiences a repeated changing process, that is, from the monotonous descending to the appearance of a maximum, then to monotonous rise, and finally to the appearance of a maximum again. With the increase of the quantum noise intensity Q, the curve experiences a changing process from the monotonous rise to the appearance of a maximum, and finally to the monotonous descending. The increase of the quantum noise with cross-correlation between the real and imaginary parts will lead to the fall of the whole curve, but not affect the form of the time evolution of C(t).

  1. The influence of periodic wind turbine noise on infrasound array measurements

    Science.gov (United States)

    Pilger, Christoph; Ceranna, Lars

    2017-02-01

    Aerodynamic noise emissions from the continuously growing number of wind turbines in Germany are creating increasing problems for infrasound recording systems. These systems are equipped with highly sensitive micro pressure sensors accurately measuring acoustic signals in a frequency range inaudible to the human ear. Ten years of data (2006-2015) from the infrasound array IGADE in Northern Germany are analysed to quantify the influence of wind turbine noise on infrasound recordings. Furthermore, a theoretical model is derived and validated by a field experiment with mobile micro-barometer stations. Fieldwork was carried out 2004 to measure the infrasonic pressure level of a single horizontal-axis wind turbine and to extrapolate the sound effect for a larger number of nearby wind turbines. The model estimates the generated sound pressure level of wind turbines and thus enables for specifying the minimum allowable distance between wind turbines and infrasound stations for undisturbed recording. This aspect is particularly important to guarantee the monitoring performance of the German infrasound stations I26DE in the Bavarian Forest and I27DE in Antarctica. These stations are part of the International Monitoring System (IMS) verifying compliance with the Comprehensive Nuclear-Test-Ban Treaty (CTBT), and thus have to meet stringent specifications with respect to infrasonic background noise.

  2. Noise in brain activity engenders perception and influences discrimination sensitivity.

    Science.gov (United States)

    Bernasconi, Fosco; De Lucia, Marzia; Tzovara, Athina; Manuel, Aurelie L; Murray, Micah M; Spierer, Lucas

    2011-12-07

    Behavioral and brain responses to identical stimuli can vary with experimental and task parameters, including the context of stimulus presentation or attention. More surprisingly, computational models suggest that noise-related random fluctuations in brain responses to stimuli would alone be sufficient to engender perceptual differences between physically identical stimuli. In two experiments combining psychophysics and EEG in healthy humans, we investigated brain mechanisms whereby identical stimuli are (erroneously) perceived as different (higher vs lower in pitch or longer vs shorter in duration) in the absence of any change in the experimental context. Even though, as expected, participants' percepts to identical stimuli varied randomly, a classification algorithm based on a mixture of Gaussians model (GMM) showed that there was sufficient information in single-trial EEG to reliably predict participants' judgments of the stimulus dimension. By contrasting electrical neuroimaging analyses of auditory evoked potentials (AEPs) to the identical stimuli as a function of participants' percepts, we identified the precise timing and neural correlates (strength vs topographic modulations) as well as intracranial sources of these erroneous perceptions. In both experiments, AEP differences first occurred ~100 ms after stimulus onset and were the result of topographic modulations following from changes in the configuration of active brain networks. Source estimations localized the origin of variations in perceived pitch of identical stimuli within right temporal and left frontal areas and of variations in perceived duration within right temporoparietal areas. We discuss our results in terms of providing neurophysiologic evidence for the contribution of random fluctuations in brain activity to conscious perception.

  3. Influences of Modulated Noise on Normalized Intensity Fluctuation in a Single-Mode Laser

    Institute of Scientific and Technical Information of China (English)

    WANG Jun; CAO Li; WU Da-Jin

    2004-01-01

    @@ The influences of the two forms of modulated noises, i.e. the bias signal-modulated noise and the direct signalmodulated noise, on the normalized intensity fluctuation (NIF) are investigated, and the results of the two forms of modulation are compared in detail. We find that a minimum for the case of the bias signal modulation appears in the curve of the dependence of the NIF upon the quantum and pump noise intensities when the correlation coefficient between the quantum noise and the pump noise is negative. However, the NIF for the case of the direct signal modulation is independent of the correlation coefficient between the two noises. Moreover, at the same parameter region, the NIF for the bias signal modulation is only one-eighth as much as that for the direct signal modulation.

  4. [Influence of environmental noise on sleep quality and sleeping disorders-implications for health].

    Science.gov (United States)

    Kohlhuber, M; Bolte, G

    2011-12-01

    Environmental noise is a well-known risk factor influencing sleep-wake behavior and sleep quality. Epidemiologic studies have shown that environmental noise is regarded as the most annoying environmental factor. Noise causes modifications in physiologic and mental functions and may result in health outcomes like elevated blood pressure and ischemic heart disease. Reactions to high sound levels during sleep are decreased sleep intensity, arousals, and increased stress hormone secretion. Effects of poor sleep quality are reduced cognitive performance, tiredness, and psychosomatic symptoms. Long-term consequences of recurrent sleep loss due to environmental noise may be heart disease and increased medication intake. Arousals occur especially due to single noise events and intermittent noise. Laboratory and field studies showed no habituation of physiologic parameters to high sound levels. Sleep is especially sensitive to noise; therefore, sound levels during nighttime should be much lower than during daytime.

  5. Influence of barrier tops on noise levels: new BEM calculations

    DEFF Research Database (Denmark)

    Pigasse, Gilles; Kragh, Jørgen; Cutanda Henriquez, Vicente

    2012-01-01

    a complex geometry such as a threepanel top. The results show that the T-shaped barrier offers most noise reduction compared to the others. It can indeed bring up to 6.6 dB extra noise reduction at a position 40 m behind the barrier compared to a regular barrier. This study also shows that the noise......The Danish Road Directorate is currently investigating the possibility to optimise noise barriers by using specially shaped tops. The noise level at different positions behind the noise barrier has been calculated using the boundary element method with the help of the OpenBEM software....... The simulated situation is a barrier between a residential area and a motorway. The highway is modelled as a two-lane road and the sound levels are predicted at 10 m, 20 m and 40 m behind the barrier, respectively. Seven different types of barriers were tested including L-, T- and Y-tops as well as more...

  6. Investigation of the influence of extra noises in seed beams on continuous-variable entanglement generation

    Institute of Scientific and Technical Information of China (English)

    Shang Ya-Na; Yan Zhi-Hui; Jia Xiao-Jun; Su Xiao-Long; Xie Chang-De

    2011-01-01

    The influence of the extra classical noises in seed beams on the entanglement between the signal and the idler modes of the output fields generated by a non-degenerate optical parametric amplifier operating at deamplification is investigated theoretically and experimentally. With the increase of the extra classical noises in the seed beams, the correlation degree of the output entangled optical fields, which is scaled by the quantum noise limit, decreases rapidly. The experimental results are in good agreement with the theoretical calculations.

  7. The influence of visual characteristics of barriers on railway noise perception.

    Science.gov (United States)

    Maffei, Luigi; Masullo, Massimiliano; Aletta, Francesco; Di Gabriele, Maria

    2013-02-15

    Noise annoyance is considered as the main effect of noise, it is a complex and multifaceted psychological concept dealing with immediate behavioral and evaluative aspects. In the last decades the research has intensely investigated the correlation between noise exposure and noise annoyance, nevertheless recent studies confirm that non-auditory factors influence the noise perception of individuals. In particular audio-video interaction can play a fundamental role. Today Immersive Virtual Reality (IVR) systems allow building laboratory test providing realistic experiences of the surrounding environment to detect more accurate information about the reactions of the local population. Regarding the interventions for environmental noise control the barriers represent the main solution; however some aspects related to their visual characteristic have to be further investigated. This paper presented a case study, where a sample of residents living close to a railway line assessed noise-related aspects for several barriers with different visual characteristics in an IVR laboratory test. In particular, three main factors were analyzed: the barrier type concerning the visibility of the noise source through the screen, the visual aspect of the barrier concerning some aesthetic issues and the noise level at the receiver concerning the acoustic performance of the barrier and the magnitude of the sound source. The main results of the ANOVA analysis showed that for transparent barriers Perceived Loudness and Noise Annoyance were judged lower than for opaque barriers; this difference increased as noise level increased. Copyright © 2012. Published by Elsevier B.V.

  8. Stochastic resonance subject to multiplicative and additive noise: The influence of potential asymmetries

    Science.gov (United States)

    Qiao, Zijian; Lei, Yaguo; Lin, Jing; Niu, Shantao

    2016-11-01

    The influence of potential asymmetries on stochastic resonance (SR) subject to both multiplicative and additive noise is studied by using two-state theory, where three types of asymmetries are introduced in double-well potential by varying the depth, the width, and both the depth and the width of the left well alone. The characteristics of SR in the asymmetric cases are different from symmetric ones, where asymmetry has a strong influence on output signal-to-noise ratio (SNR) and optimal noise intensity. Even optimal noise intensity is also associated with the steepness of the potential-barrier wall, which is generally ignored. Moreover, the largest SNR in asymmetric SR is found to be relatively larger than the symmetric one, which also closely depends on noise intensity ratio. In addition, a moderate cross-correlation intensity between two noises is good for improving the output SNR. More interestingly, a double SR phenomenon is observed in certain cases for two correlated noises, whereas it disappears for two independent noises. The above clues are helpful in achieving weak signal detection under heavy background noise.

  9. Influence of Signal and Noise on Statistical Fluctuation of Single-Mode Laser System

    Institute of Scientific and Technical Information of China (English)

    XU Da-Hai; CHENG Qing-Hua; CAO Li; WU Da-Jin

    2006-01-01

    On the basis of calculating the steady-state mean normalized intensity fluctuation of a signal-mode laser system driven by both colored pump noise with signal modulation and the quantum noise with cross-correlation between its real and imaginary parts, we analyze the influence of modulation signal, noise, and its correlation form on the statistical fluctuation of the laser system. We have found that when the amplitude of modulation signal weakens and its frequency quickens, the statistical fluctuation will reduce rapidly. The statistical fluctuation of the laser system can be restrained by reducing the intensity of pump noise and quantum noise. Moreover, with prolonging of colored cross-correlation time, the statistical fluctuation of laser system experiences a repeated changing process, that is, from decreasing to augmenting,then to decreasing, and finally to augmenting again. With the decreasing of the value of cross-correlation coefficient, the statistical fluctuation will decrease too. When the cross-correlation form between the real part and imaginary part of quantum noise is zero correlation, the statistical fluctuation of laser system has a minimum. Compared with the influence of intensity of pump noise, the influence of intensity of quantum noise on the statistical fluctuation is smaller.

  10. Influence of the Karman Vortex Street on the Broadband Noise Generated from a Multiblade Fan

    Institute of Scientific and Technical Information of China (English)

    Souichi SASAKI; Yoshio KODAMA; Hidechito HAYASHI; Makoto HATAKEYAMA

    2005-01-01

    In the prediction theory for the broadband noise generated from a multiblade fan, the vortices in the Karman vortex street was divided into n pieces. The frequency distribution of the noise was estimated so that the Strouhal number could become constant even if the wake is spread by the diffusion. From the results of the measurement of the internal flow of the fan, it was found that the noise was related to the wake characteristics of the specific location in the scroll casing where the relative flow velocity was high. The noise operating in the vicinity of the maximum efficiency point of the fan was distributed over the domain from 500 Hz to 1250 Hz. It was experimentally proved that the influence of the Karman vortex street on the noise in the domains of high and low frequencies did not exist when the distribution of the estimated sound pressure level corresponded to the measured broadband noise.

  11. Influence of Periodic Stiffenning on Flanking Noise Transmission

    DEFF Research Database (Denmark)

    Domadiya, Parthkumar Gandalal; Dickow, Kristoffer Ahrens; Andersen, Lars

    2011-01-01

    In this paper, a finite-element model is utilized for analysis of noise transmission in a lightweight structure consisting of a source panel subjected to external forces, a receiver panel used to measure the output, and a panel in between acting as a transmission path. Each panel consists of two ...

  12. Guidelines for roadless area campsite spacing to minimize impact of human-related noises.

    Science.gov (United States)

    Tom Dailey; Dave. Redman

    1975-01-01

    This report offers guidelines for campsite spacing and location in roadless areas to allow several levels of insulation from noise impacts between camping parties. The guidelines are based on the distance that different human-related noises travel in a variety of outdoor settings. The physical and psychological properties of these noises are described and discussed....

  13. The influence of diffraction gratings relief noise on the intensity distribution in diffraction orders

    Science.gov (United States)

    Kolyuchkin, V. V.; Odinokov, S. B.

    2016-08-01

    The method of security hologram quality inspection, in which the relief phase parameters are determined by registering results of the intensity distribution in diffraction orders, is known. The profile of relief as a harmonious distribution is represented. Deviation of the real relief profile from the ideal profile, another words phase relief noise, influence on the accuracy of this method. In the paper, on the assumption of homogeneity of the phase relief noise, the mathematical expressions for evaluating the influence of the phase relief noise on the intensity distribution in the diffraction orders are represented. Parameters of the correlation functions approximation describing the phase relief noise are determined. The dependence of the intensity values from the standard deviation of the phase relief noise is represented.

  14. The Influence of Realistic Reynolds Numbers on Slat Noise Simulations

    Science.gov (United States)

    Lockard, David P.; Choudhari, Meelan M.

    2012-01-01

    The slat noise from the 30P/30N high-lift system has been computed using a computational fluid dynamics code in conjunction with a Ffowcs Williams-Hawkings solver. Varying the Reynolds number from 1.71 to 12.0 million based on the stowed chord resulted in slight changes in the radiated noise. Tonal features in the spectra were robust and evident for all Reynolds numbers and even when a spanwise flow was imposed. The general trends observed in near-field fluctuations were also similar for all the different Reynolds numbers. Experiments on simplified, subscale high-lift systems have exhibited noticeable dependencies on the Reynolds number and tripping, although primarily for tonal features rather than the broadband portion of the spectra. Either the 30P/30N model behaves differently, or the computational model is unable to capture these effects. Hence, the results underscore the need for more detailed measurements of the slat cove flow.

  15. Influence of urban morphology on total noise pollution: multifractal description.

    Science.gov (United States)

    Ariza-Villaverde, Ana B; Jiménez-Hornero, Francisco J; Gutiérrez De Ravé, Eduardo

    2014-02-15

    Exposure to ambient noise levels above 65 dB can cause public health problems. The spatial distribution of this kind of pollution is linked to various elements which make up the urban form, such as construction density, the existence of open spaces and the shape and physical position of buildings. Since urban morphology displays multifractal behaviour, the present research studies for the first time the relationship between total noise pollution and urban features, such as street width and building height by means of a joint multifractal spectrum in two neighbourhoods of the city of Cordoba (Andalusia, Spain). According to the results, the joint multifractal spectrum reveals a positive correlation between the total noise pollution and the street width to building height ratio, this being more evident when urban morphology is regular. The information provided by the multifractal analysis completes the description obtained by using urban indexes and landscape metrics and might be useful for urban planning once the linkage between both frameworks has been done.

  16. The influence of preconceptions on perceived sound reduction by environmental noise barriers.

    Science.gov (United States)

    Joynt, Jennifer L R; Kang, Jian

    2010-09-15

    The paper presents research that answers three main questions: (1) Do preconceptions held about the constituent materials of an environmental noise barrier affect how people perceive the barrier will perform at attenuating noise? (2) Does aesthetic preference influence the perception of how a barrier will perform? (3) Are barriers, which are deemed more aesthetically pleasing, more likely to be perceived as better noise attenuators? In a virtual reality setting with film to improve the contextual realism of the intersensory interaction test, participants were required to compare the perceived effectiveness of five standard 'in-situ' noise barriers, including concrete, timber, metal, transparent acrylic and a vegetative screen. The audio stimulus was held at a constant sound pressure level (SPL), whilst the visual stimulus changed, as the influential factor. As the noise levels projected during the study were held constant, it was possible to attribute the participants' perception of noise attenuation by the barriers, to preconceptions of how the varying barrier material would attenuate noise. There was also an inverse correlation between aesthetics and perception of how a noise barrier would perform. The transparent and deciduous vegetation barriers, judged most aesthetically pleasing, were judged as the least effective at attenuating noise.

  17. The influence of ambient noise on maternal behavior in a Bornean sun bear (Helarctos malayanus euryspilus).

    Science.gov (United States)

    Owen, Megan A; Hall, Suzanne; Bryant, Lisa; Swaisgood, Ronald R

    2014-01-01

    Anthropogenic noise has become a pervasive feature of both marine and terrestrial habitats worldwide. While a comprehensive understanding of the biologically significant impacts of noise on wildlife is lacking, concerns regarding its influence persist. Noise is also a common feature in the zoological setting, and much can be learned regarding the species-typical response to ambient noise by studying animals in captivity. Here we correlate behavioral and vocal patterns in a Bornean sun bear (Helarctos malayanus euryspilus) mother and cub with ambient noise levels during the 6-month post-partum period. We hypothesized that loud ambient noise would be correlated with changes in behavior, and predicted that noise would be negatively correlated with maternal care behavior, potentially masking cub vocalizations or providing a distraction to the mother. Contrary to expectation, we found that the mother spent significantly more time attending to her cub (P=0.03) on loud days. We also found that she tended to spend less time feeding (P=0.08); however her time spent resting was not affected. The cub was approximately twice as vocal on loud days, although these results were not statistically significant (humming: P=0.10; squawks/cries: P=0.14). Taken together, these results suggest that the behavioral response to ambient noise may have potential energetic costs, and as a result efforts should be made to reduce ambient noise exposure during the post-partum period.

  18. INFLUENCE OF STOCHASTIC NOISE STATISTICS ON KALMAN FILTER PERFORMANCE BASED ON VIDEO TARGET TRACKING

    Institute of Scientific and Technical Information of China (English)

    Chen Ken; Napolitano; Zhang Yun; Li Dong

    2010-01-01

    The system stochastic noises involved in Kalman filtering are preconditioned on being ideally white and Gaussian distributed. In this research,efforts are exerted on exploring the influence of the noise statistics on Kalman filtering from the perspective of video target tracking quality. The correlation of tracking precision to both the process and measurement noise covariance is investigated; the signal-to-noise power density ratio is defined; the contribution of predicted states and measured outputs to Kalman filter behavior is discussed; the tracking precision relative sensitivity is derived and applied in this study case. The findings are expected to pave the way for future study on how the actual noise statistics deviating from the assumed ones impacts on the Kalman filter optimality and degradation in the application of video tracking.

  19. Fractal EEG analysis with Higuchi's algorithm of low-frequency noise exposition on humans

    Science.gov (United States)

    Panuszka, Ryszard; Damijan, Zbigniew; Kasprzak, Cezary

    2004-05-01

    Authors used methods based on fractal analysis of EEG signal to assess the influence of low-frequency sound field on the human brain electro-potentials. The relations between LFN (low-frequency noise) and change in fractal dimension EEG signal were measured with stimulations tones. Three types of LFN stimuli were presented; each specified dominant frequency and sound-pressure levels (7 Hz at 120 dB, 18 Hz at 120 dB, and 40 Hz at 110 dB). Standard EEG signal was recorded before, during, and after subject's exposure for 35 min. LFN. Applied to the analysis fractal dimension of EEG-signal Higuchis algorithm. Experiments show LFN influence on complexity of EEG-signal with calculated Higuchi's algorithm. Observed increase of mean value of Higuchi's fractal dimension during exposition to LFN.

  20. Complexity in neurobiology: perspectives from the study of noise in human motor systems.

    Science.gov (United States)

    Balasubramaniam, Ramesh; Torre, Kjerstin

    2012-01-01

    This article serves as an introduction to the themed special issue on "Complex Systems in Neurobiology." The study of complexity in neurobiology has been sensitive to the stochastic processes that dominate the micro-level architecture of neurobiological systems and the deterministic processes that govern the macroscopic behavior of these systems. A large body of research has traversed these scales of interest, seeking to determine how noise at one spatial or temporal scale influences the activity of the system at another scale. In introducing this special issue, we pay special attention to the history of inquiry in complex systems and why scientists have tended to favor linear, causally driven, reductionist approaches in Neurobiology. We follow this with an elaboration of how an alternative approach might be formulated. To illustrate our position on how the sciences of complexity and the study of noise can inform neurobiology, we use three systematic examples from the study of human motor control and learning: 1) phase transitions in bimanual coordination; 2) balance, intermittency, and discontinuous control; and 3) sensorimotor synchronization and timing. Using these examples and showing that noise is adaptively utilized by the nervous system, we make the case for the studying complexity with a perspective of understanding the macroscopic stability in biological systems by focusing on component processes at extended spatial and temporal scales. This special issue continues this theme with contributions in topics as diverse as neural network models, physical biology, motor learning, and statistical physics.

  1. Influence of perturbative phase noise on active coherent polarization beam combining system.

    Science.gov (United States)

    Ma, Pengfei; Zhou, Pu; Wang, Xiaolin; Ma, Yanxing; Su, Rongtao; Liu, Zejin

    2013-12-02

    In this manuscript, the influence of perturbative phase noise on active coherent polarization beam combining (CPBC) system is studied theoretically and experimentally. By employing a photo-detector to obtain phase error signal for feedback loop, actively coherent polarization beam combining of two 20 W-level single mode polarization-maintained (PM) fiber amplifiers are demonstrated with more than 94% combining efficiency. Then the influence of perturbative phase noise on active CPBC system is illustrated by incorporating a simulated phase noise signal in one of the two amplifiers. Experimental results show that the combining efficiency of the CPBC system is susceptible to the frequency or amplitude of the perturbative phase noise. In order to ensure the combining efficiency of the unit of CPBC system higher than 90%, the competence of our active phase control module for high power operation is discussed, which suggests that it could be worked at 100s W power level. The relationship between residual phase noise of the active controller and the normalized voltage signal of the photo-detector is developed and validated experimentally. Experimental results correspond exactly with the theoretically analyzed combining efficiency. Our method offers a useful approach to estimate the influence of phase noise on CPBC system.

  2. The influence of noise sources on cross-correlation amplitudes

    CERN Document Server

    Hanasoge, Shravan M

    2012-01-01

    We use analytical examples and asymptotic forms to examine the mathematical structure and physical meaning of the seismic cross correlation measurement. We show that in general, cross correlations are not Green's functions of medium, and may be very different depending on the source distribution. The modeling of noise sources using spatial distributions as opposed to discrete collections of sources is emphasized. When stations are illuminated by spatially complex source distributions, cross correlations show arrivals at a variety of time lags, from zero to the maximum surface-wave arrival time. Here, we demonstrate the possibility of inverting for the source distribution using the energy of the full cross-correlation waveform. The interplay between the source distribution and wave attenuation in determining the functional dependence of cross correlation energies on station-pair distance is quantified. Without question, energies contain information about wave attenuation. However, the accurate interpretation o...

  3. Modeling of road traffic noise and estimated human exposure in Fulton County, Georgia, USA.

    Science.gov (United States)

    Seong, Jeong C; Park, Tae H; Ko, Joon H; Chang, Seo I; Kim, Minho; Holt, James B; Mehdi, Mohammed R

    2011-11-01

    Environmental noise is a major source of public complaints. Noise in the community causes physical and socio-economic effects and has been shown to be related to adverse health impacts. Noise, however, has not been actively researched in the United States compared with the European Union countries in recent years. In this research, we aimed at modeling road traffic noise and analyzing human exposure in Fulton County, Georgia, United States. We modeled road traffic noise levels using the United States Department of Transportation Federal Highway Administration Traffic Noise Model implemented in SoundPLAN®. After analyzing noise levels with raster, vector and façade maps, we estimated human exposure to high noise levels. Accurate digital elevation models and building heights were derived from Light Detection And Ranging survey datasets and building footprint boundaries. Traffic datasets were collected from the Georgia Department of Transportation and the Atlanta Regional Commission. Noise level simulation was performed with 62 computers in a distributed computing environment. Finally, the noise-exposed population was calculated using geographic information system techniques. Results show that 48% of the total county population [N=870,166 residents] is potentially exposed to 55 dB(A) or higher noise levels during daytime. About 9% of the population is potentially exposed to 67 dB(A) or higher noises. At nighttime, 32% of the population is expected to be exposed to noise levels higher than 50 dB(A). This research shows that large-scale traffic noise estimation is possible with the help of various organizations. We believe that this research is a significant stepping stone for analyzing community health associated with noise exposures in the United States.

  4. Human responses to noise and vibration aboard ships

    NARCIS (Netherlands)

    Houben, M.M.J.; Kurt, R.; Khalid, H.; Zoet, P.; Bos, J.E.; Turan, O.

    2012-01-01

    Within the EU FP7 project SILENV, noise and vibration measurements were carried out on several ships. These objective measures were accompanied by subjective measures recorded through questionnaires. With this, we developed models describing the relationship between the levels of noise and vibration

  5. Influence of Multiharmonics Excitation on Rattle Noise in Automotive Gearboxes

    Directory of Open Access Journals (Sweden)

    Y. Kadmiri

    2011-01-01

    Full Text Available We consider the automotive gearbox rattle noise resulting from vibro-impacts that can occur between the idle gears under excessive velocity fluctuations of the shaft-driving gears imposed by engine torque fluctuation. Even if the rattling phenomenon has no consequence on reliability, it may be particularly annoying for vehicle interior sound quality and acoustic comfort. The main parameters governing such kind of vibrations are the excitation source associated with engine torque fluctuation which can be modeled by an imposed displacement of the driveline, the inertia of the idle gear, the drag torque acting during the free flight motion, and the impact laws. In the case of rattle, it is reasonable to assume that duration of impacts between teeth is very short compared to the excitation period. Then, these impacts are modeled by a coefficient of restitution law. The excitation source is not composed only with fundamental component but also with other harmonic components. This study presents some effects of these additional components on the dynamic response of the idle gear.

  6. Influence of Raman effect on the noise characteristics in a dual pump FOPA

    Institute of Scientific and Technical Information of China (English)

    CHENG Xiao-peng; YU Chong-xiu; DENG Yun-yi; SANG Xin-zhu; YUAN Jin-hui; RAO Lan

    2011-01-01

    Influence induced by Raman effect on the noise characteristics of a depleted and lossy dual pump fiber optical parametric amplifier (FOPA) is investigated.Taking the Raman effect into account,the modified coupled amplitude equations are firstly built,then the influences of Raman effect on the Stokes and anti-Stokes wavelengths with different initial signal powers are further analyzed.Besides,the effect on the FOPA gain is also shown with the same initial signal power and constant noise figure (NF).

  7. A 3 year update on the influence of noise on performance and behavior

    Directory of Open Access Journals (Sweden)

    Charlotte Clark

    2012-01-01

    Full Text Available The effect of noise exposure on human performance and behavior continues to be a focus for research activities. This paper reviews developments in the field over the past 3 years, highlighting current areas of research, recent findings, and ongoing research in two main research areas: Field studies of noise effects on children′s cognition and experimental studies of auditory distraction. Overall, the evidence for the effects of external environmental noise on children′s cognition has strengthened in recent years, with the use of larger community samples and better noise characterization. Studies have begun to establish exposure-effect thresholds for noise effects on cognition. However, the evidence remains predominantly cross-sectional and future research needs to examine whether sound insulation might lessen the effects of external noise on children′s learning. Research has also begun to explore the link between internal classroom acoustics and children′s learning, aiming to further inform the design of the internal acoustic environment. Experimental studies of the effects of noise on cognitive performance are also reviewed, including functional differences in varieties of auditory distraction, semantic auditory distraction, individual differences in susceptibility to auditory distraction, and the role of cognitive control on the effects of noise on understanding and memory of target speech materials. In general, the results indicate that there are at least two functionally different types of auditory distraction: One due to the interruption of processes (as a result of attention being captured by the sound, another due to interference between processes. The magnitude of the former type is related to individual differences in cognitive control capacities (e.g., working memory capacity; the magnitude of the latter is not. Few studies address noise effects on behavioral outcomes, emphasizing the need for researchers to explore noise

  8. An examination of the effects of various noise on physiological sensibility responses by using human EEG

    Energy Technology Data Exchange (ETDEWEB)

    Cho, W. H.; Lee, J. K.; Son, T. Y.; Hwang, S. H.; Choi, H. [Sungkyunkwan University, Suwon (Korea, Republic of); Lee, M. S. [Hyundai Motor Company, Hwaseong (Korea, Republic of)

    2013-12-15

    This study investigated human stress levels based on electroencephalogram (EEG) data and carried out a subjective evaluation analysis about noise. Visual information is very important for finding human's emotional state. And relatively more previous works have been done than those using auditory stimulus. Since there are fewer previous works, we thought that using auditory stimulus is good choice for our study. Twelve human subjects were exposed to classic piano, ocean wave, army alarm, ambulance, and mosquito noises. We used two groups of comfortable and uncomfortable noises are to see the difference between the definitely different two groups to confirm usefulness of using this setting of experiment. EEG data were collected during the experimental session. The subjects were tested in a soundproof chamber and asked to minimize blinking, head movement, and swallowing during the experiment. The total time of the noise experiment included the time of the relaxation phase, during which the subjects relaxed in silence for 10 minutes. The relaxation phase was followed by a 20 -second noise exposure. The alpha band activities of the subjects were significantly decreased for the ambulance and mosquito noises, as it compared to the classic piano and ocean wave noises. The alpha band activities of the subjects decreased by 12.8 ± 2.3% for the ocean wave noise, decreased by 32.0 ± 5.4% for the army alarm noise, decreased by 34.5 ± 6.7% for the ambulance noise and decreased by 58.3 ± 9.1% for the mosquito noise compared to that of classic piano. On the other hand, their beta band activities were significantly increased for the ambulance and mosquito noises as it compared to classic piano and ocean wave. The beta band activities of the subjects increased by 7.9 ± 1.7% for the ocean wave noise, increased by 20.6 ± 5.3% for the army alarm noise, increased by 48.0 ± 7.5% for the ambulance noise and increased by 61.9 ± 11.2% for the mosquito noise, as it is compared

  9. Effects of exposure to noise and indoor air pollution on human perception and symptoms

    DEFF Research Database (Denmark)

    Witterseh, Thomas; Wargocki, Pawel; Fang, Lei

    1999-01-01

    was modified by playing a recording of ventilation noise. Thirty female subjects, six at a time, occupied the office for 4.4 hours. The subjects assessed the air quality, the noise, and the indoor environment upon entering the office and on six occasions during occupation. Furthermore, SBS symptoms......The objective of the present study was to investigate human perception and SBS symptoms when people are exposed simultaneously to different levels of air pollution and ventilation noise. The air quality in an office was modified by placing or removing a carpet and the background noise level...

  10. STUDY ON NOISE LEVEL GENERATED BY HUMAN ACTIVITIES IN SIBIU CITY, ROMANIA

    Directory of Open Access Journals (Sweden)

    Cristina STANCA-MOISE

    2014-10-01

    Full Text Available In this paper I have proposed an analysis and monitoring of the noise sources in the open spaces of air traffic, rail and car in Sibiu. From centralizing data obtained from the analysis of the measurements performed with equipment noise levels, we concluded that the noise and vibration produced by means of Transportation (air, road, rail can affect human health if they exceed limits. Noise is present and part of our lives and always a source of pollution as any of modern man is not conscious.

  11. A chamber-experiment investigation of the interaction between perceptions of noise and odor in humans.

    Science.gov (United States)

    Pan, Zhiwei; Kjaergaard, Søren K; Mølhave, Lars

    2003-10-01

    This study was designed to investigate human comfort and health effects following exposure to noise and odor and to explore the interaction between perceptions of noise and odor in humans. Nine healthy subjects were randomly exposed to noise, odor, and their combination, in a 3 x 3 Latin square design for 80 min in an exposure chamber. Continuous noise was broadcast at an average level of 75 dBA by a loudspeaker, and odor was provided by furfurylmercaptan (a coffee-aroma constituent). A standardized 28-item questionnaire, together with mood-scale ratings, nasal dimensions by acoustic rhinometry, addition tests for distraction, and skin humidity, were performed before and at the end of exposure. In the questionnaire investigation, the perceived "sound level" was significantly affected by noise and the combined exposures, while "odor intensity", "air quality", and "need more ventilation" was significantly affected by odor and the combined exposures. Perceptions of symptoms became worse with increasing exposure time, such as perceived "dry nose" and "sleepiness" by odor and combined exposures, "headache" by noise, "concentration difficulty", "general well being", and "stressed by being in the chamber" by noise, odor and combined exposures. In addition, the occurrence of interactions was analyzed by comparison of the ratings of perceived "sound level", "odor intensity", "air quality", and "need more ventilation" during the combined exposure with two single exposures. Insignificant interaction was found but it indicated a decreased tendency to perceptions of discomfort from "odor intensity", "air quality", and "need for more ventilation" when noise was added to odor exposure. It may be concluded that noise and odor cause discomfort in humans. Moreover, the study might indicate that additions of noise reduce (mask) the perception of discomfort from odor, and additions of odor have no or little affect on the perception of noise.

  12. STUDY THE INFLUENCE OF H3BO3 ON THE ZINC ELECTROPLATING USING ELECTROCHEMICAL NOISE TECHNIQUE

    Institute of Scientific and Technical Information of China (English)

    Z.Zhang; C.S.Wu; Q.Y.Cai; Y.L.Cheng; F.H.Cao; J.Q.Zhang; C.N.Cao

    2004-01-01

    The influence of H3BO3 on the zinc electroplating was studied using electrochemical noise technique, cyclic voltammetry and steady-state polarization method. The results showed that,under the experimental conditions, the deposition of zinc followed the mechanism of two-dimensional nucleation and subsequent grain growth. The addition of H3BO3 into the electroplating solution prominently changes the nucleation and growth kinetics of zinc deposits, which is directly related to the features of electrocrystallization noise and the corresponding structure of the elec.trodeposits. The results also shown that the electrochemical noise (EN) technique can give more information about the electrodeposits structure and electroplating mechanism than other normal electrochemical measurements can give, such as steady-state polarization method and cyclic voltammetry technique.

  13. Investigating binocular summation in human vision using complementary fused external noise

    Science.gov (United States)

    Howell, Christopher L.; Olson, Jeffrey T.

    2016-05-01

    The impact noise has on the processing of visual information at various stages within the human visual system (HVS) is still an open research area. To gain additional insight, twelve experiments were administered to human observers using sine wave targets to determine their contrast thresholds. A single frame of additive white Gaussian noise (AWGN) and its complement were used to investigate the effect of noise on the summation of visual information within the HVS. A standard contrast threshold experiment served as the baseline for comparisons. In the standard experiment, a range of sine wave targets are shown to the observers and their ability to detect the targets at varying contrast levels were recorded. The remaining experiments added some form of noise (noise image or its complement) and/or an additional sine wave target separated between one to three octaves to the test target. All of these experiments were tested using either a single monitor for viewing the targets or with a dual monitor presentation method for comparison. In the dual monitor experiments, a ninety degree mirror was used to direct each target to a different eye, allowing for the information to be fused binocularly. The experiments in this study present different approaches for delivering external noise to the HVS, and should allow for an improved understanding regarding how noise enters the HVS and what impact noise has on the processing of visual information.

  14. Modeling of the Simultaneous Influence of the Thermal Noise and the Phase Noise in Space Communication Systems

    Directory of Open Access Journals (Sweden)

    O. Baran

    2010-12-01

    Full Text Available Our work deals with studies of a noise behavior in space communication systems. Two most important noise types the additive thermal noise and the multiplicative phase noise, respectively, are included. A simple model of the narrowband communication system is created and simulated in the Ansoft Designer system simulator. The additive thermal noise is modeled as AWGN in a communication channel. The phase noise is produced in transmitter and receiver oscillators. The main intention is to investigate the receiver filter bandwidth decrease effect on powers of both noise types. Results proposed in this paper show that for defined system conditions and for a certain filter bandwidth value, the power of the multiplicative phase noise equals to the additive thermal noise power. Another decrease of the filter bandwidth causes the phase noise power exceeding. To demonstrate the noise behavior transparently, input system parameters are properly selected. All simulation results are documented by theoretical calculations. Simulation outcomes express a good coincidence with presumptions and calculations.

  15. Influences of low-frequency and other noises produced by wind turbines: An epidemiological literature review.

    Science.gov (United States)

    Kubo, Tatsuhiko; Hasunuma, Hideki; Morimatsu, Yoshitaka; Fujino, Yoshihisa; Hara, Kunio; Ishitake, Tatsuya

    2017-01-01

    Objectives Due to its' environment-friendly and clean energy characteristics, wind power has been increasingly used globally, particularly in advanced countries. However, concerns about health hazards, especially due to low-frequency and other noises generated from wind turbines, have been reported repeatedly. In order to manage adverse health effects appropriately, regulatory standards or guidelines that consider the health of residents need to be developed. To provide a scientific basis for the development of such regulatory standards and guidelines, this paper conducted a literature review to analyze epidemiological studies involving residents living in the vicinity of wind farms.Methods Using the PubMED database, epidemiological papers that examined the health effects of noises produced by wind turbines were searched and collected. Additional papers were collected from the abstracts presented at relevant international academic conferences such as the Inter-Noise 2013 and Wind Turbine Noise 2015. An evidence table comprising the study design, subjects, exposure assessment, outcomes, confounders, and research results of each selected study was created.Results A total of 11 papers were collected (2 of which were abstracts from the international academic conferences). These studies reported outcomes such as perception of noises, annoyance caused by the noises, and the association of the noises with stress and sleeplessness. Significant associations between the noises or annoyance produced by wind turbines and subjective adverse health effects were reported repeatedly. Two studies reported an odds ratio of 1.1 for an increase of 1 dB in the A-weighted sound pressure level as a factor representing the influence level. For other factors, it was not possible to compare the magnitude of the impact among the collected studies. Individual attitudes toward wind power and landscapes, economic benefits of wind farms, visibility of wind turbines, sensitivity to sounds

  16. Prior implicit knowledge shapes human threshold for orientation noise

    DEFF Research Database (Denmark)

    Christensen, Jeppe H; Bex, Peter J; Fiser, József

    2015-01-01

    , resulting in an image-class-specific threshold that changes the shape and position of the dipper function according to image class. These findings do not fit a filter-based feed-forward view of orientation coding, but can be explained by a process that utilizes an experience-based perceptual prior...... of the expected local orientations and their noise. Thus, the visual system encodes orientation in a dynamic context by continuously combining sensory information with expectations derived from earlier experiences....

  17. [Influence of intraoperative noise protection on postoperative pain: demonstrated exemplified by total knee arthroplasty].

    Science.gov (United States)

    Keshmiri, A; Wolf, T; Wiech, O; Benditz, A; Grifka, J; Springorum, H

    2014-02-01

    It is known that implied memory of intraoperative noise influences postoperative pain. The aim of this study was to evaluate the influence of different intraoperative noise protection methods during total knee arthroplasty on postoperative pain scores. A total of 83 patients were included in this prospectively designed, double-blind trial and underwent total knee arthroplasty with psoas compartment and sciatic nerve regional anesthesia and additionally propofol sedation. After randomization patients were assigned either to the noise protection group, the music group or the control group. Postoperative pain scores (VAS) were evaluated in each group. In the three different time intervals evaluated there were no significant differences between the groups. Also the pain maxima for each postoperative day showed no significant difference but there was a slight trend to the advantage of the music group. Even though there were no significant effects of music or noise protection on postoperative pain scores, it can be concluded, as has been done by many other authors that music should be used in the perioperative setting for general patient comfort.

  18. Effects of exposure to noise and indoor air pollution on human perception and symptoms

    DEFF Research Database (Denmark)

    Witterseh, Thomas; Wargocki, Pawel; Fang, Lei

    1999-01-01

    The objective of the present study was to investigate human perception and SBS symptoms when people are exposed simultaneously to different levels of air pollution and ventilation noise. The air quality in an office was modified by placing or removing a carpet and the background noise level...... was modified by playing a recording of ventilation noise. Thirty female subjects, six at a time, occupied the office for 4.4 hours. The subjects assessed the air quality, the noise, and the indoor environment upon entering the office and on six occasions during occupation. Furthermore, SBS symptoms...... of the occupants were recorded throughout the exposure period. During occupation, the subjects performed simulated office work. The results show that elevated air pollution and noise in an office can interact and negatively affect office workers by increasing the prevalence of SBS symptoms. A moderate increase...

  19. INFLUENCE OF OCEAN INTERNAL WAVE ON PROPAGATION OF UNDERWATER RADIATION NOISE

    Institute of Scientific and Technical Information of China (English)

    YE Chun-sheng; SHEN Guo-guang

    2004-01-01

    The underwater acoustic field influenced by a selected ocean internal wave was computed using the Parabolic Equation (PE) method and split-step difference algorithm in this paper. Acoustic field is formed by sound source with different frequency covering the range of radiation noise of ships and submarines. Owing to the adoption of complex variables, sparse matrix, Gaussian source and analysis on the grid size, numerical results are achieved smoothly. The results show that internal wave's influence on underwater sound can't be neglected, especially for higher sound frequency. So it's necessary to take internal wave into account in identifying radiation noise of ships and submarines, namely for sound intensity, transmission loss and spectra shape.

  20. INFLUENCE OF NOISE AND DELAY ON REACTION-DIFFUSION RECURRENT NEURAL NETWORKS

    Institute of Scientific and Technical Information of China (English)

    Li Wu

    2006-01-01

    In this paper, the influence of the noise and delay upon the stability property of reaction-diffusion recurrent neural networks (RNNs) with the time-varying delay is discussed. The new and easily verifiable conditions to guarantee the mean value exponential stability of an equilibrium solution are derived. The rate of exponential convergence can be estimated by means of a simple computation based on these criteria.

  1. Effects of ultrasonic noise on the human body-a bibliographic review.

    Science.gov (United States)

    Smagowska, Bożena; Pawlaczyk-Łuszczyńska, Małgorzata

    2013-01-01

    Industrial noise in the working environment has adverse effects on human hearing; literature and private studies confirm that. It has been determined that significant changes in the hearing threshold level occur in the high frequency audiometry, i.e., in the 8-20 kHz frequency range. Therefore, it is important to determine the effect of ultrasonic noise (10-40 kHz) on the human body in the working environment. This review describes hearing and nonhearing effects (thermal effects, subjective symptoms and functional changes) of the exposure to noise emitted by ultrasound devices. Many countries have standard health exposure limits to prevent effects of the exposure to ultrasonic noise in the working environment.

  2. Evaluation of human exposure to the noise from large wind turbine generators

    Science.gov (United States)

    Shepherd, K. P.; Grosveld, F. W.; Stephens, D. G.

    1983-01-01

    The human perception of a nuisance level of noise was quantified in tests and attempts were made to define criteria for acceptable sound levels from wind turbines. Comparisons were made between the sound necessary to cause building vibration, which occurred near the Mod-1 wind turbine, and human perception thresholds for building noise and building vibration. Thresholds were measured for both broadband and impulsive noise, with the finding that noise in the 500-2000 Hz region, and impulses with a 1 Hz fundamental, were most noticeable. Curves were developed for matching a receiver location with expected acoustic output from a machine to determine if the sound levels were offensive. In any case, further data from operating machines are required before definitive criteria can be established.

  3. Cylinder wake influence on the tonal noise and aerodynamic characteristics of a NACA0018 airfoil

    Science.gov (United States)

    Takagi, Y.; Fujisawa, N.; Nakano, T.; Nashimoto, A.

    2006-11-01

    The influence of cylinder wake on discrete tonal noise and aerodynamic characteristics of a NACA0018 airfoil is studied experimentally in a uniform flow at a moderate Reynolds number. The experiments are carried out by measuring sound pressure levels and spectrum, separation and the reattachment points, pressure distribution, fluid forces, mean-flow and turbulence characteristics around the airfoil with and without the cylinder wake. Present results indicate that the tonal noise from the airfoil is suppressed by the influence of the cylinder wake and the aerodynamic characteristics are improved in comparison with the case without the cylinder wake. These are mainly due to the separation control of boundary layers over the airfoil caused by the wake-induced transition, which is observed by surface flow visualization with liquid- crystal coating. The PIV measurements of the flow field around the airfoil confirm that highly turbulent velocity fluctuation of the cylinder wake induces the transition of the boundary layers and produces an attached boundary layer over the airfoil. Then, the vortex shedding phenomenon near the trailing edge of pressure surface is removed by the influence of the wake and results in the suppression of tonal noise.

  4. Influence of embedding parameters and noise in center of pressure recurrence quantification analysis.

    Science.gov (United States)

    Hasson, Christopher J; Van Emmerik, Richard E A; Caldwell, Graham E; Haddad, Jeffrey M; Gagnon, Jeff L; Hamill, Joseph

    2008-04-01

    Recurrence quantification analysis (RQA) can extract the dynamics of postural control from center of pressure (CoP) data by quantifying the system's repeatability, complexity, and local dynamic stability through several variables. Computation of these variables requires the selection of suitable embedding parameters for state space reconstruction (i.e. time delay and embedding dimension); however, it is unclear how the parameters influence RQA variables when examining noisy CoP data. This study evaluated the sensitivity of RQA variables to embedding parameter values and noise level, and assessed methods of selecting embedding parameters for CoP data. Five healthy male subjects maintained quiet stance for 30s while the anterior-posterior CoP was measured. The effect of noise was evaluated by adding uniform white noise of increasing amplitude to the raw CoP signal. The magnitude of all RQA variables decreased with increasing noise amplitude for all subjects. A sensitivity analysis was performed by systematically altering the embedding parameters for the raw data with and without a selected level of added noise. The key result was that, for all subjects, the RQA variables were sensitive to the embedding parameter values and the level of noise in the CoP data. Finally, the performance of false nearest neighbors and average displacement algorithms for choosing embedding parameters was evaluated. Both methods gave clear and consistent results for all subjects with either raw or noisy data. The results suggest that careful selection of embedding parameters is essential when using RQA to examine postural control based on noisy CoP data.

  5. How does stochastic resonance work within the human brain? - Psychophysics of internal and external noise

    Energy Technology Data Exchange (ETDEWEB)

    Aihara, Takatsugu [ATR Computational Neuroscience Laboratories, 2-2-2 Hikaridai, Seika-cho, Soraku-gun, Kyoto 619-0288 (Japan); Kitajo, Keiichi [Laboratory for Dynamics of Emergent Intelligence, RIKEN Brain Science Institute, Wako, Saitama 351-0198 (Japan); PRESTO, Japan Science and Technology Agency (JST), 4-1-8 Honcho Kawaguchi, Saitama 332-0012 (Japan); Nozaki, Daichi [Educational Physiology Laboratory, Graduate School of Education, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Yamamoto, Yoshiharu, E-mail: yamamoto@p.u-tokyo.ac.jp [Educational Physiology Laboratory, Graduate School of Education, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2010-10-05

    We review how research on stochastic resonance (SR) in neuroscience has evolved and point out that the previous studies have overlooked the interaction between internal and external noise. We propose a new psychometric function incorporating SR effects, and show that a Bayesian adaptive method applied to the function efficiently estimates the parameters of the function. Using this procedure in visual detection experiments, we provide significant insight into the relationship between internal and external noise in SR within the human brain.

  6. Investigation of LO-leakage cancellation and DC-offset influence on flicker-noise in X-band mixers

    DEFF Research Database (Denmark)

    Michaelsen, Rasmus; Johansen, Tom; Tamborg, Kjeld

    2012-01-01

    This paper describes an investigation on the influences in 1/f noise of LO-leakage and DC-offset cancellation for X-band mixers. Conditions for LO-leakage cancellation and zero DC-offset is derived. Measurements on a double balanced diode mixer shows an improvement in noise figure from 14.3dB to 12...

  7. Ubiquitous crossmodal Stochastic Resonance in humans: auditory noise facilitates tactile, visual and proprioceptive sensations.

    Directory of Open Access Journals (Sweden)

    Eduardo Lugo

    Full Text Available BACKGROUND: Stochastic resonance is a nonlinear phenomenon whereby the addition of noise can improve the detection of weak stimuli. An optimal amount of added noise results in the maximum enhancement, whereas further increases in noise intensity only degrade detection or information content. The phenomenon does not occur in linear systems, where the addition of noise to either the system or the stimulus only degrades the signal quality. Stochastic Resonance (SR has been extensively studied in different physical systems. It has been extended to human sensory systems where it can be classified as unimodal, central, behavioral and recently crossmodal. However what has not been explored is the extension of this crossmodal SR in humans. For instance, if under the same auditory noise conditions the crossmodal SR persists among different sensory systems. METHODOLOGY/PRINCIPAL FINDINGS: Using physiological and psychophysical techniques we demonstrate that the same auditory noise can enhance the sensitivity of tactile, visual and propioceptive system responses to weak signals. Specifically, we show that the effective auditory noise significantly increased tactile sensations of the finger, decreased luminance and contrast visual thresholds and significantly changed EMG recordings of the leg muscles during posture maintenance. CONCLUSIONS/SIGNIFICANCE: We conclude that crossmodal SR is a ubiquitous phenomenon in humans that can be interpreted within an energy and frequency model of multisensory neurons spontaneous activity. Initially the energy and frequency content of the multisensory neurons' activity (supplied by the weak signals is not enough to be detected but when the auditory noise enters the brain, it generates a general activation among multisensory neurons of different regions, modifying their original activity. The result is an integrated activation that promotes sensitivity transitions and the signals are then perceived. A physiologically

  8. The Role of Visual Noise in Influencing Mental Load and Fatigue in a Steady-State Motion Visual Evoked Potential-Based Brain-Computer Interface.

    Science.gov (United States)

    Xie, Jun; Xu, Guanghua; Luo, Ailing; Li, Min; Zhang, Sicong; Han, Chengcheng; Yan, Wenqiang

    2017-08-14

    As a spatial selective attention-based brain-computer interface (BCI) paradigm, steady-state visual evoked potential (SSVEP) BCI has the advantages of high information transfer rate, high tolerance to artifacts, and robust performance across users. However, its benefits come at the cost of mental load and fatigue occurring in the concentration on the visual stimuli. Noise, as a ubiquitous random perturbation with the power of randomness, may be exploited by the human visual system to enhance higher-level brain functions. In this study, a novel steady-state motion visual evoked potential (SSMVEP, i.e., one kind of SSVEP)-based BCI paradigm with spatiotemporal visual noise was used to investigate the influence of noise on the compensation of mental load and fatigue deterioration during prolonged attention tasks. Changes in α, θ, θ + α powers, θ/α ratio, and electroencephalography (EEG) properties of amplitude, signal-to-noise ratio (SNR), and online accuracy, were used to evaluate mental load and fatigue. We showed that presenting a moderate visual noise to participants could reliably alleviate the mental load and fatigue during online operation of visual BCI that places demands on the attentional processes. This demonstrated that noise could provide a superior solution to the implementation of visual attention controlling-based BCI applications.

  9. A region finding method to remove the noise from the images of the human hand gesture recognition system

    Science.gov (United States)

    Khan, Muhammad Jibran; Mahmood, Waqas

    2015-12-01

    The performance of the human hand gesture recognition systems depends on the quality of the images presented to the system. Since these systems work in real time environment the images may be corrupted by some environmental noise. By removing the noise the performance of the system can be enhanced. So far different noise removal methods have been presented in many researches to eliminate the noise but all have its own limitations. We have presented a region finding method to deal with the environmental noise that gives better results and enhances the performance of the human hand gesture recognition systems so that the recognition rate of the system can be improved.

  10. Influence of correspondence noise and spatial scaling on the upper limit for spatial displacement in fully-coherent random-dot kinematogram stimuli.

    Directory of Open Access Journals (Sweden)

    Srimant P Tripathy

    Full Text Available Correspondence noise is a major factor limiting direction discrimination performance in random-dot kinematograms. In the current study we investigated the influence of correspondence noise on Dmax, which is the upper limit for the spatial displacement of the dots for which coherent motion is still perceived. Human direction discrimination performance was measured, using 2-frame kinematograms having leftward/rightward motion, over a 200-fold range of dot-densities and a four-fold range of dot displacements. From this data Dmax was estimated for the different dot densities tested. A model was proposed to evaluate the correspondence noise in the stimulus. This model summed the outputs of a set of elementary Reichardt-type local detectors that had receptive fields tiling the stimulus and were tuned to the two directions of motion in the stimulus. A key assumption of the model was that the local detectors would have the radius of their catchment areas scaled with the displacement that they were tuned to detect; the scaling factor k linking the radius to the displacement was the only free parameter in the model and a single value of k was used to fit all of the psychophysical data collected. This minimal, correspondence-noise based model was able to account for 91% of the variability in the human performance across all of the conditions tested. The results highlight the importance of correspondence noise in constraining the largest displacement that can be detected.

  11. Simultaneous influence of hydrostatic pressure and temperature on diamagnetic susceptibility of impurity doped quantum dots under the aegis of noise

    Science.gov (United States)

    Saha, Surajit; Ganguly, Jayanta; Bera, Aindrila; Ghosh, Manas

    2016-11-01

    We explore the diamagnetic susceptibility (DMS) of impurity doped quantum dot (QD) in presence of Gaussian white noise and under the combined influence of hydrostatic pressure (HP) and temperature (T). Presence of noise and also its mode of application discernibly affect the DMS profile. Application of HP and T invites greater delicacies in the observed DMS profiles. However, whereas the interplay between T and noise comes out to be extremely sensitive in fabricating the DMS profile, the pressure-noise interplay appears to be not that much noticeable. Under all conditions of temperature and pressure, the presence of multiplicative noise diminishes the value of DMS in comparison with that in presence of its additive analogue. The present study renders a deep insight into the remarkable role played by the interplay between noise, hydrostatic pressure and temperature in controlling the effective confinement imposed on the system which bears unquestionable relevance.

  12. Characterizing noise in nonhuman vocalizations: Acoustic analysis and human perception of barks by coyotes and dogs

    Science.gov (United States)

    Riede, Tobias; Mitchell, Brian R.; Tokuda, Isao; Owren, Michael J.

    2005-07-01

    Measuring noise as a component of mammalian vocalizations is of interest because of its potential relevance to the communicative function. However, methods for characterizing and quantifying noise are less well established than methods applicable to harmonically structured aspects of signals. Using barks of coyotes and domestic dogs, we compared six acoustic measures and studied how they are related to human perception of noisiness. Measures of harmonic-to-noise-ratio (HNR), percent voicing, and shimmer were found to be the best predictors of perceptual rating by human listeners. Both acoustics and perception indicated that noisiness was similar across coyote and dog barks, but within each species there was significant variation among the individual vocalizers. The advantages and disadvantages of the various measures are discussed.

  13. The influence of stressors on biochemical reactions--a review of present scientific findings with noise.

    Science.gov (United States)

    Maschke, C; Rupp, T; Hecht, K

    2000-03-01

    For every faculty of perception there is, according to the degree of irritation, a biochemical or psychobiological activation. This is also true for the perception of sound or noise. Initially, these processes allow for the adjustment of the organism to a changed situation (eustress). Prolonged effects of stressors may ultimately lead to regulatory disturbances and induce pathological processes (distress). The pathogenetic concept that psychobiological stresses (e.g. noise) may be connected with the well-known risk factors of cardiovascular diseases, through excitation of the central nervous system, is based on the known stress models. The central connective factors are the activation hormones of the adrenal gland, also referred to as stress hormones. From blood and urine parameters recorded in epidemiological and experimental studies under the influence of acute or chronic noise, a simplified model of the pathogenetic mechanism has been developed. Fundamental conditions for future assessing the "stress hormones" have been derived, by means of which premorbid conditions can be determined on a population or group basis.

  14. ELECTROCHEMICAL NOISE ANALYSIS OF THE INFLUENCE OF THE Zn2+ IONS CONCENTRATION ON ZINC ELECTROPLATING

    Institute of Scientific and Technical Information of China (English)

    Z. Zhang; C.S. Wu; Q.Y. Cai; F.H. Cao; J.Q. Zhang

    2005-01-01

    The influence of the concentration of Zn2+ ions on zinc electroplating process was investigated by means of electrochemical noise (EN) and cyclic voltammetry methods in conjunction with the scanning electron microscopy (SEM) technique. It was found that the EN generated during the electroplating of dentritic or large polymeric zinc deposit has large potential oscillation amplitude and positive potential drift while the compact zinc deposit possesses small noise amplitude and little potential drifi. With the change of rate determining step from diffusion-control through mixed-control to activation-control, the maximum relative energy obtained from wavelet analysis defined from the region with larger scales to those with smaller scales, and the EDP (relative energy distribution plot) can be us, as 'fingerprints" of EN to characterize the electroplating process and the deposit structure. The results also showed that electrochemical noise technique can give more information about the electrodeposit structure than other normal electrochemical measurements, such as linear potential sweep method and cyclic voltammetry technique.

  15. How much does language proficiency by non-native listeners influence speech audiometric tests in noise?

    Science.gov (United States)

    Warzybok, Anna; Brand, Thomas; Wagener, Kirsten C; Kollmeier, Birger

    2015-01-01

    The current study investigates the extent to which the linguistic complexity of three commonly employed speech recognition tests and second language proficiency influence speech recognition thresholds (SRTs) in noise in non-native listeners. SRTs were measured for non-natives and natives using three German speech recognition tests: the digit triplet test (DTT), the Oldenburg sentence test (OLSA), and the Göttingen sentence test (GÖSA). Sixty-four non-native and eight native listeners participated. Non-natives can show native-like SRTs in noise only for the linguistically easy speech material (DTT). Furthermore, the limitation of phonemic-acoustical cues in digit triplets affects speech recognition to the same extent in non-natives and natives. For more complex and less familiar speech materials, non-natives, ranging from basic to advanced proficiency in German, require on average 3-dB better signal-to-noise ratio for the OLSA and 6-dB for the GÖSA to obtain 50% speech recognition compared to native listeners. In clinical audiology, SRT measurements with a closed-set speech test (i.e. DTT for screening or OLSA test for clinical purposes) should be used with non-native listeners rather than open-set speech tests (such as the GÖSA or HINT), especially if a closed-set version in the patient's own native language is available.

  16. Influence of sound-conditioning on noise-induced susceptibility of distortion-product otoacoustic emissions.

    Science.gov (United States)

    Luebke, Anne E; Stagner, Barden B; Martin, Glen K; Lonsbury-Martin, Brenda L

    2015-07-01

    Cochlear damage caused by loud sounds can be attenuated by "sound-conditioning" methods. The amount of adaptation for distortion product otoacoustic emissions (DPOAEs) measured in alert rabbits previously predicted an ear's susceptibility to a subsequent noise exposure. The present study investigated if sound-conditioning influenced the robustness of such DPOAE adaptation, and if such conditioning elicited more protection by increasing the amount of DPOAE adaptation. Toward this end, rabbits were divided into two study groups: (1) experimental animals exposed to a sound-conditioning protocol, and (2) unconditioned control animals. After base-line measures, all rabbits were exposed to an overstimulation paradigm consisting of an octave band noise, and then re-assessed 3 weeks post-exposure to determine permanent changes in DPOAEs. A major result was that prior sound-conditioning protected reductions in DPOAE levels by an average of 10-15 dB. However, DPOAE adaptation decreased with sound-conditioning, so that such conditioning was no longer related to noise-induced reductions in DPOAEs. Together, these findings suggest that sound-conditioning affected neural pathways other than those that likely mediate DPOAE adaptation (e.g., medial olivocochlear efferent and/or middle-ear muscle reflexes).

  17. Human response to wind turbine noise - perception, annoyance and moderating factors

    Energy Technology Data Exchange (ETDEWEB)

    Pedersen, Eja

    2007-05-15

    The aims of this thesis were to describe and gain an understanding of how people who live in the vicinity of wind turbines are affected by wind turbine noise, and how individual, situational and visual factors, as well as sound properties, moderate the response. Methods A cross-sectional study was carried out in a flat, mainly rural area in Sweden, with the objective to estimate the prevalence of noise annoyance and to examine the dose-response relationship between A-weighted sound pressure levels (SPLs) and perception of and annoyance with wind turbine noise. Subjective responses were obtained through a questionnaire (n = 513; response rate: 68%) and outdoor, A-weighted SPLs were calculated for each respondent. To gain a deeper understanding of the observed noise annoyance, 15 people living in an area were interviewed using open-ended questions. The interviews were analysed using the comparative method of Grounded Theory (GT). An additional cross-sectional study, mainly exploring the influence of individual and situational factors, was carried out in seven areas in Sweden that differed with regard to terrain (flat or complex) and degree of urbanization (n = 765; response rate: 58%). To further explore the impact of visual factors, data from the two cross-sectional studies were tested with structural equation modelling. A proposed model of the influence of visual attitude on noise annoyance, also comprising the influence of noise level and general attitude, was tested among respondents who could see wind turbines versus respondents who could not see wind turbines from their dwelling, and respondents living in flat versus complex terrain. Dose-response relationships were found both for perception of noise and for noise annoyance in relation to A-weighted SPLs. The risk of annoyance was enhanced among respondents who could see at least one turbine from their dwelling and among those living in a rural in comparison with a suburban area. Noise from wind turbines was

  18. Human Response to Helicopter Noise: A Test of A-Weighting

    Science.gov (United States)

    1991-11-01

    34Environmental Quality Technology" Work Unit NN-TGO, "Department of Defense (DOD) Noise Source Human Response Characterization." Cosponsors of this research were...CH53E Indoo 50 CH5E Idoo92 dB Control SEL / O 4 0

  19. Human diffusion and city influence

    CERN Document Server

    Lenormand, Maxime; Tugores, Antònia; Ramasco, José J

    2015-01-01

    Cities are characterized by concentrating population, economic activity and services. However, not all cities are equal and hierarchy in terms of influence at local, regional or global scales naturally emerges. Traditionally, there have been important efforts to describe this hierarchy by indirect measures such the sharing of company headquarters, traffic by air, train or boats or economical exchanges. In this work, we take a different approach and introduce a method that uses geolocated Twitter information to quantify the impact of cities on rural or other urban areas. Since geolocated tweets are becoming a global phenomenon, the method can be applied at a world-wide scale. We focus on $58$ cities and analyze the mobility patterns of people after visiting them for the first time. Cities such as Rome and Paris appear consistently as those with largest area covered by Twitter users after their visit and as those attracting visitors most diverse in origin. The study is also performed discerning users mobility b...

  20. Human decision making based on variations in internal noise: an EEG study.

    Directory of Open Access Journals (Sweden)

    Sygal Amitay

    Full Text Available Perceptual decision making is prone to errors, especially near threshold. Physiological, behavioural and modeling studies suggest this is due to the intrinsic or 'internal' noise in neural systems, which derives from a mixture of bottom-up and top-down sources. We show here that internal noise can form the basis of perceptual decision making when the external signal lacks the required information for the decision. We recorded electroencephalographic (EEG activity in listeners attempting to discriminate between identical tones. Since the acoustic signal was constant, bottom-up and top-down influences were under experimental control. We found that early cortical responses to the identical stimuli varied in global field power and topography according to the perceptual decision made, and activity preceding stimulus presentation could predict both later activity and behavioural decision. Our results suggest that activity variations induced by internal noise of both sensory and cognitive origin are sufficient to drive discrimination judgments.

  1. Influence of external white noise on the formation of Tsallis' velocity distribution function: A molecular dynamics study

    Science.gov (United States)

    Nouri Kadijani, M.; Abbasi, H.

    2016-09-01

    Dynamics of a dust layer suspending in a plasma and interacting through a Yukawa-type potential is considered. In the small affinity limit, the influence of an external white noise on the formation of Tsallis' velocity distribution function is studied through molecular dynamics simulation. The characteristic length of the noise is much smaller than the system size that causes a number of subsystems (islands) to be formed with the size similar to the noise one. The external noise leads to the temperature fluctuation in each island. Therefore, a stochastic formalism based on a Langevin equation for the fluctuating temperature is presented. The approach provides a dynamical reason how a fluctuating temperature takes a system to a unique class of quasi-equilibrium states. In particular, the dependence of the model systems on the noise parameters is explained. The non-extensive parameter is obtained through which the small affinity limit can be defined.

  2. Noise-induced phase transition in the model of human virtual stick balancing

    CERN Document Server

    Zgonnikov, Arkady

    2016-01-01

    Humans face the task of balancing dynamic systems near an unstable equilibrium repeatedly throughout their lives. Much research has been aimed at understanding the mechanisms of intermittent control in the context of human balance control. The present paper deals with one of the recent developments in the theory of human intermittent control, namely, the double-well model of noise-driven control activation. We demonstrate that the double-well model can reproduce the whole range of experimentally observed distributions under different conditions. Moreover, we show that a slight change in the noise intensity parameter leads to a sudden shift of the action point distribution shape, that is, a phase transition is observed.

  3. Noise-driven activation in human intermittent control: a double-well potential model

    CERN Document Server

    Zgonnikov, Arkady

    2014-01-01

    In controlling unstable systems humans switch intermittently between the passive and active behavior instead of controlling the system in a continuous manner. The notion of noise-driven control activation provides a richer alternative to the conventional threshold-based models of intermittent motor control. The present study represents the control activation as a random walk in a continuously changing double-well potential. The match between the proposed model and the previous data on human balancing of virtual stick prompts that the double-well approach can aid in explaining complex dynamics of human behavior in control processes.

  4. Prediction of the influence of reverberation on binaural speech intelligibility in noise and in quiet.

    Science.gov (United States)

    Rennies, Jan; Brand, Thomas; Kollmeier, Birger

    2011-11-01

    Reverberation usually degrades speech intelligibility for spatially separated speech and noise sources since spatial unmasking is reduced and late reflections decrease the fidelity of the received speech signal. The latter effect could not satisfactorily be predicted by a recently presented binaural speech intelligibility model [Beutelmann et al. (2010). J. Acoust. Soc. Am. 127, 2479-2497]. This study therefore evaluated three extensions of the model to improve its predictions: (1) an extension of the speech intelligibility index based on modulation transfer functions, (2) a correction factor based on the room acoustical quantity "definition," and (3) a separation of the speech signal into useful and detrimental parts. The predictions were compared to results of two experiments in which speech reception thresholds were measured in a reverberant room in quiet and in the presence of a noise source for listeners with normal hearing. All extensions yielded better predictions than the original model when the influence of reverberation was strong, while predictions were similar for conditions with less reverberation. Although model (3) differed substantially in the assumed interaction of binaural processing and early reflections, its predictions were very similar to model (2) that achieved the best fit to the data.

  5. Olfactory Performance Can Be Influenced by the Presentation Order, Background Noise, and Positive Concurrent Feedback.

    Science.gov (United States)

    Walliczek-Dworschak, Ute; Pellegrino, Robert; Lee, Shangwa; Hummel, Cornelia; Hähner, Antje; Hummel, Thomas

    2016-10-01

    Sniffin' Sticks have become a popular procedure to measure overall olfactory functionality with 3 subtest: phenyl ethyl alcohol threshold test (T), discrimination (D), and identification (I). However, several procedural components specified by the original paper have not been tested nor has the impact of deviations been measured. The aim of the present work was to measure olfactory performance under modified testing procedures. First, the reverse order of subtests (IDT) was compared with more standard practices (TDI). Next, the possible impact of background noise and positive concurrent feedback were assessed. A total of 120 individuals participated in the study where the 3 conditional experiments, each involving 40 participants, were completed. Testing procedures that reversed the presentation order of subtests (I->D->T) scored a significantly lower overall TDI score than standard testing order with the threshold subtest being the most influenced. Additionally, nonverbal background noise lowered overall olfactory performance while concurrent feedback modulated threshold performance. These results emphasize the importance of testing parameters where olfactory perception and tasks may be modulated by adaptation and attentional distraction, respectively. This study helped furthermore to demonstrate that the investigated 3 deviations from the standard procedure revealed a significant impact on the performance outcome in olfactory assessment using the Sniffin' Sticks.

  6. Deformation and stiffness of spur gear teeth and their influence on gear noise

    Directory of Open Access Journals (Sweden)

    Silvia MEDVECKÁ-BEŇOVÁ

    2015-12-01

    Full Text Available Gear teeth are deformed due to the load. The deformation of gear teeth is causing some negative as well as positive effects. A tooth has a complex shape and due to the complex shape of the teeth, a theoretical determination of the deformation is difficult. The existing experimental techniques are based on static deflection measurements gearing loaded of constant force or seismic measurement deviations at slow rotation. Recently, at ever faster evolving computer technology and the available literature, we can encounter modern numerical methods, such as finite element method (FEM, which can serve as methods for the determination of teeth of gearing. The article is devoted to the problems of gearing stiffness analysis. The problem is solved for spur gears. Deformation analysis solved by FEM is used for calculations of the gearing stiffness. There are many influences that cause vibrations in the gearbox and that have to be taken into account already in the phase of design, manufacture, installation and operation. Detailed analysis of gearboxes manufacturers have shown that improving of the gear accuracy cannot reduce the transmission unit noise to the desired level. Only fundamental changes to the shape of the tooth and changes in production technology can achieve stronger noise reduction of gear mechanism.

  7. Influence of exchange on signal-to-noise ratio in [CoX/Pt]4 media

    Science.gov (United States)

    Zhao, Zhen; Li, Jiangnan; Wang, Longze; Wei, Dan

    2017-05-01

    In longitudinal hard disk drives, the medium Signal-to-Noise Ratio (SNR) is higher with better grain segregation or lower inter-grain exchange. In current energy assisted magnetic recording system, multilayer perpendicular media are utilized; thus, it is significant to study the influence of grain segregation on SNR, as well as the relevant percolation phenomenon, to give suggestions on the recording media design. In this study, micromagnetic recording models of Microwave Assisted Magnetic Recording (MAMR) is built up to calculate SNR to find optimized [CoX/Pt]4 media parameters such as the inter-grain exchange Agb and the anisotropy orientation distribution αθ, with different field generation layer (FGL) saturation in the spin torque oscillator (STO). The constrained relationship between Agb and αθ in MAMR have been estimated, and the medium SNR will be optimized in the perpendicular [CoX/Pt]4 with a proper but not lowest exchange.

  8. Influence of prenatal noise and music on the spatial memory and neurogenesis in the hippocampus of developing rats.

    Science.gov (United States)

    Kim, Hong; Lee, Myoung-Hwa; Chang, Hyun-Kyung; Lee, Taeck-Hyun; Lee, Hee-Hyuk; Shin, Min-Chul; Shin, Mal-Soon; Won, Ran; Shin, Hye-Sook; Kim, Chang-Ju

    2006-03-01

    During the prenatal period, the development of individual is influenced by the environmental factors. In the present study, the influence of prenatal noise and music on the spatial memory and neurogenesis in the hippocampus of developing rats was investigated. The exposure to the noise during pregnancy caused growth retardation, decreased neurogenesis in the hippocampus, and impaired spatial learning ability in pups. The exposure to music during pregnancy, on the other hand, caused increased neurogenesis in the hippocampus and enhanced spatial learning ability in pups. The present study has shown the importance of the prenatal environmental conditions for the cognition and brain development.

  9. Influence of lasers with non-white frequency noise on the design of coherent optical links

    DEFF Research Database (Denmark)

    Kakkar, Aditya; Navarro, Jaime Rodrigo; Schatz, Richard

    2017-01-01

    We experimentally demonstrate for a 28 Gbaud 64-QAM metro link that the LO frequency noise causes timing impairment. Results show the existence of LO frequency noise spectrum regimes where different design criteria apply....

  10. Through-wall imaging and characterization of human activity using ultrawideband (UWB) random noise radar

    Science.gov (United States)

    Lai, Chieh-Ping; Narayanan, Ram M.

    2005-05-01

    Recent terrorist activities and law-enforcement situations involving hostage situations underscore the need for effective through-wall imaging. Current building interior imaging systems are based on short-pulse waveforms, which require specially designed antennas to subdue unwanted ringing. In addition, periodically transmitted pulses of energy are easily recognizable by the intelligent adversary who may employ appropriate countermeasures to confound detection. A coherent polarimetric random noise radar architecture is being developed based on UWB technology and software defined radio, which has great promise in its ability to covertly image obscured targets. The main advantages of the random noise radar lie in two aspects: first, random noise waveform has an ideal "thumbtack" ambiguity function, i.e., its down range and cross range resolution can be separately controlled, thus providing unambiguous high resolution imaging at any distance; second, random noise waveform is inherently low probability of intercept (LPI) and low probability of detection (LPD), i.e., it is immune from detection, jamming, and interference. Thus, it is an ideal candidate sensor for covert imaging of obscured regions in hostile environments. The coherency in the system can be exploited to field a fully-polarimetric system that can take advantage of polarization features in target recognition. Moving personnel can also be detected using Doppler processing. Simulation studies are used to analyze backscattered signals from the walls, and humans and other targets behind the walls. Real-time data processing shows human activity behind the wall and human target tracking. The high resolution provides excellent multipath and clutter rejection.

  11. Influence of molecular noise on the growth of single cells and bacterial populations.

    Directory of Open Access Journals (Sweden)

    Mischa Schmidt

    Full Text Available During the last decades experimental studies have revealed that single cells of a growing bacterial population are significantly exposed to molecular noise. Important sources for noise are low levels of metabolites and enzymes that cause significant statistical variations in the outcome of biochemical reactions. In this way molecular noise affects biological processes such as nutrient uptake, chemotactic tumbling behavior, or gene expression of genetically identical cells. These processes give rise to significant cell-to-cell variations of many directly observable quantities such as protein levels, cell sizes or individual doubling times. In this study we theoretically explore if there are evolutionary benefits of noise for a growing population of bacteria. We analyze different situations where noise is either suppressed or where it affects single cell behavior. We consider two specific examples that have been experimentally observed in wild-type Escherichia coli cells: (i the precision of division site placement (at which molecular noise is highly suppressed and (ii the occurrence of noise-induced phenotypic variations in fluctuating environments. Surprisingly, our analysis reveals that in these specific situations both regulatory schemes [i.e. suppression of noise in example (i and allowance of noise in example (ii] do not lead to an increased growth rate of the population. Assuming that the observed regulatory schemes are indeed caused by the presence of noise our findings indicate that the evolutionary benefits of noise are more subtle than a simple growth advantage for a bacterial population in nutrient rich conditions.

  12. Cultural and Demographic Factors Influencing Noise Exposure Estimates from Use of Portable Listening Devices in an Urban Environment

    Science.gov (United States)

    Fligor, Brian J.; Levey, Sandra; Levey, Tania

    2014-01-01

    Purpose: This study examined listening levels and duration of portable listening devices (PLDs) used by people with diversity of ethnicity, education, music genre, and PLD manufacturer. The goal was to estimate participants' PLD noise exposure and identify factors influencing user behavior. Method: This study measured listening levels of 160…

  13. Cultural and Demographic Factors Influencing Noise Exposure Estimates from Use of Portable Listening Devices in an Urban Environment

    Science.gov (United States)

    Fligor, Brian J.; Levey, Sandra; Levey, Tania

    2014-01-01

    Purpose: This study examined listening levels and duration of portable listening devices (PLDs) used by people with diversity of ethnicity, education, music genre, and PLD manufacturer. The goal was to estimate participants' PLD noise exposure and identify factors influencing user behavior. Method: This study measured listening levels of 160…

  14. On the influence of noise correlations in measurement data on basis image noise in dual-energylike x-ray imaging.

    Science.gov (United States)

    Roessl, Ewald; Ziegler, Andy; Proksa, Roland

    2007-03-01

    In conventional dual-energy systems, two transmission measurements with distinct spectral characteristics are performed. These measurements are used to obtain the line integrals of two basis material densities. Usually, the measurement process is such that the two measured signals can be treated as independent and therefore uncorrelated. Recently, however, a readout system for x-ray detectors has been introduced for which this is no longer the case. The readout electronics is designed to obtain simultaneous measurements of the total number of photons N and the total energy E they deposit in the sensor material. Practically, this is realized by a signal replication and separate counting and integrating processing units. Since the quantities N and E are (electronically) derived from one and the same physical sensor signal, they are statistically correlated. Nevertheless, the pair N and E can be used to perform a dual-energy processing following the well-known approach by Alvarez and Macovski. Formally, this means that N is to be identified with the first dual-energy measurement M1 and E with the second measurement M2. In the presence of input correlations between M1 = N and M2 = E, however, the corresponding analytic expressions for the basis image noise have to be modified. The main observation made in this paper is that for positively correlated data, as is the case for the simultaneous counting and integrating device mentioned above, the basis image noise is suppressed through the influence of the covariance between the two signals. We extend the previously published relations for the basis image noise to the case where the original measurements are not independent and illustrate the importance of the input correlations by comparing dual-energy basis image noise resulting from the device mentioned above and a device measuring the photon numbers and the deposited energies consecutively.

  15. Influence of laser scanner range measurement noise on the quantification of rock surface roughness

    Science.gov (United States)

    Khoshelham, Kourosh; Altundag, Dogan

    2010-05-01

    The roughness of rock surfaces is traditionally measured by using manual tools such as carpenter's comp and compass and disc clinometers. The manual measurements are limited to small samples at accessible parts of the rock. Terrestrial laser scanning is an attractive alternative measurement technique, which offers large coverage, high resolution, and the ability to reach inaccessible high rock faces. The application of laser scanning to the study of rock surface roughness faces a major challenge: the inherent range imprecision hinders the quantification of roughness parameters. In practice, when roughness is in millimeter scale it is often lost in the range measurement noise. The parameters derived from the data, therefore, reflect noise rather than the actual roughness of the surface. In this paper, we investigate the influence of laser scanner range measurement noise on the quantification of rock surfaces roughness. We show that measurement noise leads to the overestimation of roughness parameters. We also demonstrate the application of wavelet de-noising method to eliminating noise from laser scanner data and deriving realistic roughness parameters. A slightly metamorphosed limestone rock in the east bank of the Meuse River in southern Belgium was scanned with a Faro LS880 terrestrial laser scanner. The scanner was positioned at approximately 5 meters distance to the rock surface, and operated at the highest possible angular resolution, i.e. 0.009 degrees. The resulting point cloud contained about 1.2 million points on the rock surface with a point-spacing of 1 mm on average. According to the technical specifications of the laser scanner, the nominal range precision at a perpendicular incidence angle, which was roughly the case in our scan, is between 0.7 mm and 5.2 mm respectively for objects of 90% and 10% reflectivity at a distance of 10 m. To serve as reference roughness data were also collected manually along three profiles on the rock surface by using a

  16. Earthing the human body influences physiologic processes.

    Science.gov (United States)

    Sokal, Karol; Sokal, Pawel

    2011-04-01

    This study was designed to answer the question: Does the contact of the human organism with the Earth via a copper conductor affect physiologic processes? Subjects and experiments: Five (5) experiments are presented: experiment 1-effect of earthing on calcium-phosphate homeostasis and serum concentrations of iron (N = 84 participants); experiment 2-effect of earthing on serum concentrations of electrolytes (N = 28); experiment 3-effect of earthing on thyroid function (N = 12); experiment 4-effect of earthing on glucose concentration (N = 12); experiment 5-effect of earthing on immune response to vaccine (N = 32). Subjects were divided into two groups. One (1) group of people was earthed, while the second group remained without contact with the Earth. Blood and urine samples were examined. Earthing of an electrically insulated human organism during night rest causes lowering of serum concentrations of iron, ionized calcium, inorganic phosphorus, and reduction of renal excretion of calcium and phosphorus. Earthing during night rest decreases free tri-iodothyronine and increases free thyroxine and thyroid-stimulating hormone. The continuous earthing of the human body decreases blood glucose in patients with diabetes. Earthing decreases sodium, potassium, magnesium, iron, total protein, and albumin concentrations while the levels of transferrin, ferritin, and globulins α1, α2, β, and γ increase. These results are statistically significant. Earthing the human body influences human physiologic processes. This influence is observed during night relaxation and during physical activity. Effect of the earthing on calcium-phosphate homeostasis is the opposite of that which occurs in states of weightlessness. It also increases the activity of catabolic processes. It may be the primary factor regulating endocrine and nervous systems.

  17. The influence of low frequencies on the assessment of noise from neighbours

    DEFF Research Database (Denmark)

    Rindel, Jens Holger; Rasmussen, Birgit; Nielsen, Jesper Rye

    1996-01-01

    Lightweight building constructions often suffer from insufficient sound insulation at low frequencies. In order to investigate the degree of the problems, a laboratory experiment has been carried out. Twenty test persons have been asked to evaluate series of typical noise from neighbours, ie, two...... kinds of airborne noise and two kinds of impact noise. The noise examples were presented with two different shapings of the frequency spectrum in order to stimulate either a heavy building construction or a typical lightweight construction. The noise examples were presented at four different levels...... and combined with two levels of background noise. The two frequency shapings were different in the frequency range 25-200 Hz, but identical at higher frequencies. Dose-response curves have been derived for annoyance, disturbance of concentration and subjective loudness. It has not been possible to analyze...

  18. Complexity and multifractality of neuronal noise in mouse and human hippocampal epileptiform dynamics

    Science.gov (United States)

    Serletis, Demitre; Bardakjian, Berj L.; Valiante, Taufik A.; Carlen, Peter L.

    2012-10-01

    Fractal methods offer an invaluable means of investigating turbulent nonlinearity in non-stationary biomedical recordings from the brain. Here, we investigate properties of complexity (i.e. the correlation dimension, maximum Lyapunov exponent, 1/fγ noise and approximate entropy) and multifractality in background neuronal noise-like activity underlying epileptiform transitions recorded at the intracellular and local network scales from two in vitro models: the whole-intact mouse hippocampus and lesional human hippocampal slices. Our results show evidence for reduced dynamical complexity and multifractal signal features following transition to the ictal epileptiform state. These findings suggest that pathological breakdown in multifractal complexity coincides with loss of signal variability or heterogeneity, consistent with an unhealthy ictal state that is far from the equilibrium of turbulent yet healthy fractal dynamics in the brain. Thus, it appears that background noise-like activity successfully captures complex and multifractal signal features that may, at least in part, be used to classify and identify brain state transitions in the healthy and epileptic brain, offering potential promise for therapeutic neuromodulatory strategies for afflicted patients suffering from epilepsy and other related neurological disorders. This paper is based on chapter 5 of Serletis (2010 PhD Dissertation Department of Physiology, Institute of Biomaterials and Biomedical Engineering, University of Toronto).

  19. Human Gravity-Gradient Noise in Interferometric Gravitational-Wave Detectors

    CERN Document Server

    Thorne, K S; Thorne, Kip S.; Winstein, Carolee J.

    1999-01-01

    Among all forms of routine human activity, the one which produces the strongest gravity-gradient noise in interferometric gravitational-wave detectors (e.g. LIGO) is the beginning and end of weight transfer from one foot to the other during walking. The beginning and end of weight transfer entail sharp changes (timescale tau ~ 20msec) in the horizontal jerk (first time derivative of acceleration) of a person's center of mass. These jerk pairs, occuring about twice per second, will produce gravity-gradient noise in LIGO in the frequency band 2.5 Hz <~ f <~ 1/(2 tau) ~= 25 Hz with the form sqrt{S_h(f)} sum is over all the walking people, r_i is the distance of the i'th person from the nearest interferometer test mass, and we estimate this formula to be accurate to within a factor 3. To ensure that this noise is neglible in advanced LIGO interferometers, people should be prevented from coming nearer to the test masses than r ~= 10m. A r ~= 10m exclusion zone will also reduce to an acceptable level gravity ...

  20. Microbial consortium influence upon steel corrosion rate, using polarisation resistance and electrochemical noise techniques

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez Gayosso, M.J.; Zavala Olivares, G.; Ruiz Ordaz, N.; Juarez Ramirez, C.; Garcia Esquivel, R.; Padilla Viveros, A

    2004-10-01

    The microbiologically influenced corrosion (MIC) is a process, which affects the oil industry, particularly the hydrocarbons extraction, transport and storage. MIC evaluation has been normally based upon microbiological tests, and just a few references mention alternating methods, such as the electrochemical techniques, which can be used as criteria for their evaluation. In this work, two different electrochemical laboratory techniques, polarisation resistance and electrochemical noise were used, in order to determine the corrosion behaviour of a microbial consortium, obtained from a gas transporting pipeline, located in the southeast of Mexico. The bacteria population growth was found to be different for sessile and plancktonic microorganisms. Moreover, long incubation times were required to reach the maximum concentration of sessile bacteria. The electrochemical techniques used in this study exhibited a similar tendency on the corrosion rate behaviour with time, and values above 0.3 mm year{sup -1} were observed at the end of the experiments. The experiments were complemented with surface analysis. Scanning electron microscope observation of APIXL52 steel coupons, exposed to the consortium action, revealed bacteria presence, as well as a damaged steel surface. A type of localized corrosion was observed on the metal surface, and it was associated to the bacteria effect.

  1. Influence of sociodemographic characteristics on human mobility

    CERN Document Server

    Lenormand, Maxime; Cantu-Ros, Oliva G; Picornell, Miguel; Herranz, Ricardo; Arias, Juan Murillo; Barthelemy, Marc; Miguel, Maxi San; Ramasco, Jose J

    2014-01-01

    Human mobility has been traditionally studied using surveys that deliver snapshots of population displacement patterns. The growing accessibility to ICT information obtained from portable digital media has recently opened the possibility of going beyond such fixed pictures, exploring human behavior at high spatio-temporal resolutions. Mobile phone records, geolocated tweets, check-ins from Foursquare or geotagged photos, have contributed to this purpose at different scales from cities to countries and in different areas of the world. Many of these previous works have lacked, however, details on the attributes of the individuals. In this work, we analyze credit-card transaction records as mobility proxies and assess the influence of sociodemographic characteristics on the way people move and spend their money in cities. In particular, we focus on Barcelona and Madrid, the two most populated cities of Spain, and by examining the geolocated credit-card transactions of individuals living in the two provinces, we ...

  2. Investigation of the influence of magnetostriction and magnetic forces on transformer core noise and vibration

    Science.gov (United States)

    Phophongviwat, Teeraphon

    Transformer noise is of increasing environmental concern so continued efforts are being made by electrical steel and transformer producers to satisfy users by reducing the noise. Magnetostriction and magnetic forces are the main causes of transformer core noise and vibration. Understanding of the relationship from the core material to core structure and core vibration to core noise can help the design of low noise transformer cores. The most appropriate parameter for investigating the relationship between noise and vibration is sound pressure (in the unit of Pascals) in the frequency domain because it is not A-weighted. In this study, the side surfaces of transformer cores were found to emit higher noise than front and top surfaces at low magnetic induction. When the magnetic induction was increased, the effect of magnetic force increased and caused the front surfaces to emit higher noise. For three phase three limb transformer cores, the front surface of the middle limb generated higher noise than the outer limbs due to the effect of T-joint. However this does not translate higher noise level because of the phase difference of the vibration between the limbs. Due to this A-weighted sound power level of three phase, three limb transformer cores were shown to be lower than single phase transformer cores, although at the same cross sectional area and core window size the three phase cores has larger size.. A model, developed to separate the effects of magnetostriction and magnetic forces on transformer core vibration, showed that at low induction, magnetostriction is more significant than magnetic forces. The magnetic forces become more significant than magnetostriction when the induction is increased. Magnetostriction primarily depends on material and stress but magnetic forces principally depend on core building. Louder noise can be generated from a core built with low magnetostriction material than higher magnetostriction if the building tolerances are worse. The

  3. Influence of age and sex on hearing threshold levels in workers exposed to different intensity levels of occupational noise

    Energy Technology Data Exchange (ETDEWEB)

    Szanto, C.; Ionescu, M.

    1983-01-01

    The influence of age, sex and duration of exposure on hearing threshold level (HTL) was assessed in male and female workers exposed to occupational noise. The noise intensities were of 84 and 98 dB(A) continuous equivalent level. Large differences were noted between males and females exposed to 98 dB(A) as well as between males exposed to 98 and 83 dB(A). We concluded that exposure to 98 dB(A) accelerates the evolution of hearing loss, this trend being more pronounced in males. The 83-dB(A) intensity apparently induces a hearing loss above the values due to socioacusis. To evaluate the noxious effect of noise, the HTLs obtained in the group exposed to 98 and 83-dB(A) were compared to those of the non-exposed group of Royster and Thomas. The highest difference was found in males exposed to 98 dB(A).

  4. Exploring optical dielectric function of impurity doped quantum dots under combined influence of hydrostatic pressure and temperature and in presence of noise

    Science.gov (United States)

    Bera, Aindrila; Ghosh, Manas

    2017-01-01

    We investigate the total optical dielectric function (TODF) of impurity doped QDs under the combined influence of hydrostatic pressure (HP) and temperature and in presence of Gaussian white noise. Noise has been incorporated to the system additively and multiplicatively. Variations of HP, temperature and noise strength affect TODF profile in subtle way. And the subtlety also depends on mode of application of noise. Extrapolation of the present study would be important in understanding the effective optical properties of the system under given conditions of HP and temperature and in presence of noise.

  5. Involuntary and Persistent Environmental Noise Influences Health and Hearing in Beirut, Lebanon

    Science.gov (United States)

    Fooladi, Marjaneh M.

    2012-01-01

    Objective. This study was conducted to assess the effects of involuntary and persistent noise exposure on health and hearing among Lebanese adults in Beirut, Lebanon, where people are exposed to noise from construction sites, power generators, honking cars, and motorcycles. Methods. Using a descriptive and exploratory design with mixed methods, participants were surveyed, interviewed, and tested for hearing while street noise levels were measured near their residents and work places. Results. Self-reports of 83 Lebanese adult, who lived and worked in Beirut, helped identify common patterns in experiences such as irritability, anger, headaches, and sleep disturbances due to noise annoyance. Of those tested, 30% suffered from high-frequency hearing impairment. Our results showed that environmental sound dB had increased by 12% and sound intensity by 400% above the maximum standard level when compared to the WHO report of 1999. Conclusion. Environmental noise contributes to premature hearing loss and potentiates systemic diseases among Lebanese. PMID:22013454

  6. Influence of music and music preference on acceptable noise levels in listeners with normal hearing.

    Science.gov (United States)

    Gordon-Hickey, Susan; Moore, Robert E

    2007-05-01

    Acceptable noise level (ANL) is defined as the maximum level of background noise that an individual is willing to accept while listening to speech. The type of background noise does not affect ANL results with the possible exception of music. The purpose of this study was to determine if ANL for music was different from ANL for twelve-talker babble and investigate if there was a correlation between ANL for music samples and preference for those music samples. Results demonstrated that ANL for music tended to be better than ANL for twelve-talker babble, indicating listeners were more willing to accept music as a background noise than speech babble. The results further demonstrated that ANL for the music samples were not correlated with preference for the music samples, indicating that ANL for music was not related to music preference. Therefore, music appeared to be processed differently as a background noise than twelve-talker babble.

  7. High Intensity Pressure Noise Transmission in Human Ear: A Three Dimensional Simulation Study

    Science.gov (United States)

    Hawa, Takumi; Gan, Rong; Leckness, Kegan

    2015-03-01

    High intensity pressure noise generated by explosions and jet engines causes auditory damage and hearing loss of the military service personals, which are the most common disabilities in the veterans. Authors have investigated the high intensity pressure noise transmission from the ear canal to middle ear cavity. A fluid-structure interaction with a viscoelastic model for the tympanic membrane (TM) as well as the ossicular chain has been considered in the study. For the high intensity pressure simulation the geometry of the ear was based on a 3D finite element (FE) model of the human ear reported by Gan et al. (Ann Biomed Eng 2004). The model consists of the ear canal, TM, ossicular chain, and the middle ear cavity. The numerical approach includes two steps: 1) FE based finite-volume method simulation to compute pressure distributions in the ear canal and the middle ear cavity using CFX; and 2) FE modeling of TM and middle ear ossicles in response to high intensity sound using multi-physics analysis in ANSYS. The simulations provide the displacement of the TM/ossicular chain and the pressure fields in the ear canal and the middle ear cavity. These results are compared with human temporal bone experimental data obtained in our group. This work was supported by DOD W81XWH-14-1-0228.

  8. The influence of jet engine noise on hearing of technical staff

    Directory of Open Access Journals (Sweden)

    Wiesław Konopka

    2014-10-01

    Full Text Available Background: Due to high sound pressure levels (SPLs, noise produced by jet planes may be harmful to hearing of people working in their proximity. The aim of this study was to assess the effects of exposure to jet engine noise on technical staff hearing. Material and Methods: The study comprised 60 men, aged 24–50 years, employed in army as technical staff and exposed to jet engine noise for 6–20 years. The control group were 50 non-noise exposed males, aged 25–51 years. Exposure to noise emitted by jet engines was evaluated. Pure-tone audiometry (PTA and distortion product otoacoustic emissions (DPOAE were recorded in both groups. Results: Jet engines emitted broadband noise with spectrum dominated by components in the frequency range 315–6300 Hz (1/3-octave bands. Maximum A-weighted SPL during tests reached values of approx. 120–130 dB. Consequently, engine-servicing personnel (even in the case of a single engine test was exposed to noise (at A-weighted daily noise exposure level above 95 dB exceeding permissible levels. Averaged audiometric hearing threshold levels of technical staff were higher (≤ 17 dB HL, p < 0.001 than in the control group. Similarly, the DPOAE amplitude was lower (≤ 17 dB SPL, p < 0.01 in the noise-exposed subjects compared to the non-exposed ones. Significant reduction of DPOAE levels was mainly noted for high frequencies (3–6 kHz. Conclusions: Despite the usage of hearing protection devices, both PTA and DPOAE consistently showed poorer hearing in engine-servicing personnel vs. control group. Med Pr 2014;65(5:583–592

  9. Influence of Pre- and Post-compensation of Chromatic Dispersion on Equalization Enhanced Phase Noise in Coherent Multilevel Systems

    CERN Document Server

    Jacobsen, Gunnar; Xu, Tianhua; Popov, Sergei; Friberg, Ari T; Zhang, Yimo

    2016-01-01

    In this paper we present a comparative study in order to specify the influence of equalization enhanced phase noise (EEPN) for pre- and post-compensation of chromatic dispersion in high capacity and high constellation systems. This is - to our knowledge - the first detailed study in this area for pre-compensation systems. Our main results show that the local oscillator phase noise determines the EEPN influence in post-compensation implementations whereas the transmitter laser determines the EEPN in pre-compensation implementations. As a result of significance for the implementation of practical longer-range systems it is to be emphasized that the use of chromatic dispersion equalization in the optical domain - e.g. by the use of dispersion compensation fibers - eliminates the EEPN entirely. Thus, this seems a good option for such systems operating at high constellations in the future.

  10. How noise and language proficiency influence speech recognition by individual non-native listeners.

    Science.gov (United States)

    Zhang, Jin; Xie, Lingli; Li, Yongjun; Chatterjee, Monita; Ding, Nai

    2014-01-01

    This study investigated how speech recognition in noise is affected by language proficiency for individual non-native speakers. The recognition of English and Chinese sentences was measured as a function of the signal-to-noise ratio (SNR) in sixty native Chinese speakers who never lived in an English-speaking environment. The recognition score for speech in quiet (which varied from 15%-92%) was found to be uncorrelated with speech recognition threshold (SRTQ/2), i.e. the SNR at which the recognition score drops to 50% of the recognition score in quiet. This result demonstrates separable contributions of language proficiency and auditory processing to speech recognition in noise.

  11. Channel Influence Mitigation in Pseudo-noise Waveform Design for Radar Applications

    Directory of Open Access Journals (Sweden)

    J. S. Kulpa

    2014-04-01

    Full Text Available Noise Radar is a rapidly developing technology which uses noise or pseudo-noise waveforms as sounding signals to de- tect targets of interest. The advantages of such waveforms are no range nor velocity ambiguities, the possibility of using continuous waveform and low probability of intercept. However, the noise waveform correlation sidelobes are spread across the entire range–Doppler plane and their level is de- termined by the time-bandwidth product. Such sidelobes limit the detection capability in the multitarget environment. Several algorithms exist that decrease the sidelobe level and thus enhance dynamic range of the radar, but they are very susceptible to distortions in an analogue channel. In this paper the author presents a method to create low-sidelobe waveforms using a filtering algorithm designed for given channel, decreasing the analogue front-end impact on the final properties of the waveforms.

  12. Influence of Solid Noise Barriers on Near-Road and On-Road Air Quality

    Science.gov (United States)

    Public health concerns regarding adverse health effects for populations spending significant amounts of time near high traffic roadways has increased substantially in recent years. Roadside features, including solid noise barriers, have been investigated as potential methods to ...

  13. Instantaneous liquid release from a rail tanker: the influence of noise shields on pool shape and pool size.

    Science.gov (United States)

    Rosmuller, Nils

    2009-05-30

    In the Netherlands, the Betuweline is a dedicated freight railway. It will, among other things, be used for transportation of all kinds of hazardous materials from the Port of Rotterdam to the German Hinterland and vice versa. The line is approximately 150 km long. Alongside the line, more than 100 km noise shields have been constructed. The question is how, and to what extent, this noise shield will affect the pool shape and size of an instantaneous release of a flammable liquid, such as liquefied petroleum gas (LPG). In case of an instantaneous release of liquid from a rail tanker (50 m(3)), both risk analysts and emergency responders use a circular pool shape of about 600 m(2) would result. To assess the influence of a noise shield, a full scale test was conducted on an already constructed part of the Betuweline. A rail tanker was filled with 50 m(3) red-colored environmentally safe liquid. The liquid was instantaneously released. A very peculiar pool shape actually results due to the presence of a noise shield. A zone between the rails and the noise shield (2m wide and 90 m long) is within 2-3 min filled with 15 cm of liquid. The total pool size area was about 750 m(2). Both shape and size deviate substantially from the traditional figures. These insights are both relevant to emergency responders for disaster abatement purposes and to risk analysts for effective modeling purposes. The Dutch Ministry of Transport is examining possible strategies to deal with these results. The results of this study are based upon one single instantaneous release test. In addition, it is valuable to find out what the pool shape and size would be in case of a continuous release from the rail tanker near a noise shield.

  14. Influence of native and non-native multitalker babble on speech recognition in noise

    Directory of Open Access Journals (Sweden)

    Chandni Jain

    2014-03-01

    Full Text Available The aim of the study was to assess speech recognition in noise using multitalker babble of native and non-native language at two different signal to noise ratios. The speech recognition in noise was assessed on 60 participants (18 to 30 years with normal hearing sensitivity, having Malayalam and Kannada as their native language. For this purpose, 6 and 10 multitalker babble were generated in Kannada and Malayalam language. Speech recognition was assessed for native listeners of both the languages in the presence of native and nonnative multitalker babble. Results showed that the speech recognition in noise was significantly higher for 0 dB signal to noise ratio (SNR compared to -3 dB SNR for both the languages. Performance of Kannada Listeners was significantly higher in the presence of native (Kannada babble compared to non-native babble (Malayalam. However, this was not same with the Malayalam listeners wherein they performed equally well with native (Malayalam as well as non-native babble (Kannada. The results of the present study highlight the importance of using native multitalker babble for Kannada listeners in lieu of non-native babble and, considering the importance of each SNR for estimating speech recognition in noise scores. Further research is needed to assess speech recognition in Malayalam listeners in the presence of other non-native backgrounds of various types.

  15. Influence of musical training on understanding voiced and whispered speech in noise.

    Science.gov (United States)

    Ruggles, Dorea R; Freyman, Richard L; Oxenham, Andrew J

    2014-01-01

    This study tested the hypothesis that the previously reported advantage of musicians over non-musicians in understanding speech in noise arises from more efficient or robust coding of periodic voiced speech, particularly in fluctuating backgrounds. Speech intelligibility was measured in listeners with extensive musical training, and in those with very little musical training or experience, using normal (voiced) or whispered (unvoiced) grammatically correct nonsense sentences in noise that was spectrally shaped to match the long-term spectrum of the speech, and was either continuous or gated with a 16-Hz square wave. Performance was also measured in clinical speech-in-noise tests and in pitch discrimination. Musicians exhibited enhanced pitch discrimination, as expected. However, no systematic or statistically significant advantage for musicians over non-musicians was found in understanding either voiced or whispered sentences in either continuous or gated noise. Musicians also showed no statistically significant advantage in the clinical speech-in-noise tests. Overall, the results provide no evidence for a significant difference between young adult musicians and non-musicians in their ability to understand speech in noise.

  16. Does exposure to noise from human activities compromise sensory information from cephalopod statocysts?

    Science.gov (United States)

    Solé, Marta; Lenoir, Marc; Durfort, Mercè; López-Bejar, Manel; Lombarte, Antoni; van der Schaar, Mike; André, Michel

    2013-10-01

    Many anthropogenic noise sources are nowadays contributing to the general noise budget of the oceans. The extent to which sound in the sea impacts and affects marine life is a topic of considerable current interest both to the scientific community and to the general public. Cepaholopods potentially represent a group of species whose ecology may be influenced by artificial noise that would have a direct consequence on the functionality and sensitivity of their sensory organs, the statocysts. These are responsible for their equilibrium and movements in the water column. Controlled Exposure Experiments, including the use of a 50-400Hz sweep (RL=157±5dB re 1μPa with peak levels up to SPL=175dB re 1μPa) revealed lesions in the statocysts of four cephalopod species of the Mediterranean Sea, when exposed to low frequency sounds: (n=76) of Sepia officinalis, (n=4) Octopus vulgaris, (n=5) Loligo vulgaris and (n=2) Illex condietii. The analysis was performed through scanning (SEM) and transmission (TEM) electron microscopical techniques of the whole inner structure of the cephalopods' statocyst, especially on the macula and crista. All exposed individuals presented the same lesions and the same incremental effects over time, consistent with a massive acoustic trauma observed in other species that have been exposed to much higher intensities of sound: Immediately after exposure, the damage was observed in the macula statica princeps (msp) and in the crista sensory epithelium. Kinocilia on hair cells were either missing or were bent or flaccid. A number of hair cells showed protruding apical poles and ruptured lateral plasma membranes, most probably resulting from the extrusion of cytoplasmic material. Hair cells were also partially ejected from the sensory epithelium, and spherical holes corresponding to missing hair cells were visible in the epithelium. The cytoplasmic content of the damaged hair cells showed obvious changes, including the presence of numerous vacuoles

  17. Combined influence of hydrostatic pressure and temperature on interband emission energy of impurity doped quantum dots in presence of noise

    Science.gov (United States)

    Bera, Aindrila; Ghosh, Manas

    2016-11-01

    We explore the profiles of interband emission energy (IEE) of impurity doped quantum dots (QDs) under the simultaneous influence of hydrostatic pressure (HP) and temperature (T) and in presence and absence of Gaussian white noise. Noise has been incorporated to the system additively and multiplicatively. In this regard, modulation of IEE by the variation of several other relevant quantities such as electric field, magnetic field, confinement potential, dopant location, dopant potential and aluminium concentration has also been investigated. Gradual alteration of HP and T affects IEE discernibly. Inclusion of noise has been found to enhance or deplete the IEE depending upon its mode of application. Moreover, under given conditions of temperature and pressure, the difference between the impurity-free ground state energy and the binding energy appears to be crucial in determining whether or not the profiles of IEE would resemble that of binding energy. The findings reveal fascinating role played by noise in tailoring the IEE of doped QD system under conspicuous presence of hydrostatic pressure and temperature.

  18. The influence of noise exposure on the parameters of a convolution model of the compound action potential.

    Science.gov (United States)

    Chertoff, M E; Lichtenhan, J T; Tourtillott, B M; Esau, K S

    2008-10-01

    The influence of noise exposure on the parameters of a convolution model of the compound action potential (CAP) was examined. CAPs were recorded in normal-hearing gerbils and in gerbils exposed to a 117 dB SPL 8 kHz band of noise for various durations. The CAPs were fitted with an analytic CAP to obtain the parameters representing the number of nerve fibers (N), the probability density function [P(t)] from a population of nerve fibers, and the single-unit waveform [U(t)]. The results showed that the analytic CAP fitted the physiologic CAPs well with correlations of approximately 0.90. A subsequent analysis using hierarchical linear modeling quantified the change in the parameters as a function of both signal level and hearing threshold. The results showed that noise exposure caused some of the parameter-level functions to simply shift along the signal level axis in proportion to the amount of hearing loss, whereas others shifted along the signal level axis and steepened. Significant changes occurred in the U(t) parameters, but they were not related to hearing threshold. These results suggest that noise exposure alters the physiology underlying the CAP, some of which can be explained by a simple lack of gain, whereas others may not.

  19. Aging and Temporal Influences on Speech Perception in Reverberation and Noise.

    Science.gov (United States)

    Helfer, Karen S.

    The present study examined the interactions of age, temporal resolution, hearing loss, and consonant perception under realistic listening conditions. Four subject groups were employed, with N = 8 per group: young adults with normal hearing or sloping sensorineural hearing loss; and elderly individuals with minimal peripheral hearing loss or presbycusis. Copies of the CUNY Nonsense Syllable Test (NST) were re-recorded under four levels of reverberation in quiet and in +10 signal-to-noise ratio of cafeteria noise. The test stimuli were presented binaurally to the subjects via TDH-49 headphones. In addition, a diotic wideband gap detection task, using a 72 dBSPL presentation level, was used as a measure of temporal resolution. Results of the present investigation demonstrated that all other subject groups performed significantly poorer than the young, normal hearing adults. Scores decreased as the amount of distortion increased, although there was very little difference between performance in the two highest reverberation conditions. For reverberation alone, the young, hearing-impaired listeners obtained the lowest scores; for reverberation + noise, the older, hearing-impaired subjects performed poorest. Large within-group variability was noted in the size of the gap thresholds, and only the two groups of young subjects differed significantly on this task of temporal resolution. Correlation analyses demonstrated a strong inverse relation between age and performance in reverberation + noise, even when degree of hearing loss was partialed out. Pure -tone average, as well as NST scores in quiet and in noise alone were related strongly to performance in reverberation. Multiple regression analyses demonstrated that nonsense syllable perception in reverberation could be predicted from a combination of age, pure-tone thresholds, scores in quiet and noise, and gap threshold. Gap threshold was the strongest predictor variable for reverberation alone, while the NST score

  20. An investigation into the influence of longitudinal creepage on railway squeal noise due to lateral creepage

    NARCIS (Netherlands)

    Monk-Steel, A.D.; Thompson, D.J.; Beer, F.G. de; Janssens, M.H.A.

    2006-01-01

    Curve squeal noise is of growing concern for the railway industry as rail systems become more widespread in densely populated areas. In response to the pressure to minimise environmental pollution, there is a demand for a deeper understanding of the phenomenon and to develop a methodical approach to

  1. The influence of low frequencies on the assessment of noise from neighbours

    DEFF Research Database (Denmark)

    Rindel, Jens Holger; Rasmussen, Birgit; Nielsen, Jesper Rye

    1996-01-01

    and combined with two levels of background noise. The two frequency shapings were different in the frequency range 25-200 Hz, but identical at higher frequencies. Dose-response curves have been derived for annoyance, disturbance of concentration and subjective loudness. It has not been possible to analyze...

  2. Improving the Effectiveness of Communication Headsets with Active Noise Reduction: Influence of Control Structure

    Science.gov (United States)

    2005-04-01

    for two circumaural communication headsets with similar passive, and active, noise reductions, one with an analog feedback control system and the...the feedback control system to maintain stability of the feedback loop, as well as the presence of communication sounds sensed by the control

  3. Load influence on gear noise. [mathematical model for determining acoustic pressure level as function of load

    Science.gov (United States)

    Merticaru, V.

    1974-01-01

    An original mathematical model is proposed to derive equations for calculation of gear noise. These equations permit the acoustic pressure level to be determined as a function of load. Application of this method to three parallel gears is reported. The logical calculation scheme is given, as well as the results obtained.

  4. Influence of noise and near-resonant perturbations on bifurcations in Josephson junctions

    DEFF Research Database (Denmark)

    Svensmark, Henrik; Hansen, Jørn Bindslev; Pedersen, Niels Falsig

    1987-01-01

    The stabilization of a nonlinear system against period-doubling bifurcations by means of a periodic perturbation has been investigated. With the Josephson junction as a model system, both numerical simulations (including noise) and measurements on Josephson tunnel junctions have been performed...

  5. Research on road traffic noise and human health in India: Review of literature from 1991 to current

    Directory of Open Access Journals (Sweden)

    Dibyendu Banerjee

    2012-01-01

    Full Text Available This article reviews the literature on research conducted during the last two decades on traffic noise impacts in India. Road traffic noise studies in India are fewer and restricted only to the metropolitan areas. The studies over the years have also focused on the monitoring, recording, analysis, modeling, and to some extent mapping related themes. Negligible studies are observed in areas of physiological and sleep research exposure-effect context. Most impact studies have been associated with annoyance and attitudinal surveys only. Little scientific literature exists related to effects of traffic noise on human physiology in the Indian context. The findings of this review search and analysis observe that very little studies are available relating to traffic noise and health impacts. All of them are subjective response studies and only a small portion of them quantify the exposure-effect chain and model the noise index with annoyance. The review of papers showed that road traffic noise is a cause for annoyance to a variety of degree among the respondents. A generalization of impacts and meta-analysis was not possible due to variability of the study designs and outputs preferred.

  6. Simultaneous human detection and ranging using a millimeter-wave radar system transmitting wideband noise with an embedded tone

    Science.gov (United States)

    Gallagher, Kyle A.; Narayanan, Ram M.

    2012-06-01

    This paper describes a millimeter-wave (mm-wave) radar system that has been constructed to simultaneously range and detect humans at distances up to 82 meters. This is done by utilizing a composite signal consisting of two waveforms: a wideband noise waveform and a single tone. These waveforms are summed together and transmitted simultaneously. Matched filtering of the received and transmitted noise signals is performed to range targets with high resolution, while the received single tone signal is used for Doppler analysis. The Doppler measurements are used to distinguish between different human movements using characteristic micro-Doppler signals. Using hardware and software filters allows for simultaneous processing of both the noise and Doppler waveforms. Our measurements establish the mm-wave system's ability to detect humans up to and beyond 80 meters and distinguish between different human movements. In this paper, we describe the architecture of the multi-modal mm-wave radar system and present results on human target ranging and Doppler characterization of human movements. In addition, data are presented showing the differences in reflected signal strength between a human with and without a concealed metallic object.

  7. Noise-Induced Hearing Loss (NIHL Prediction in Humans Using a Modified Back Propagation Neural Network

    Directory of Open Access Journals (Sweden)

    Muhammad Zubair Rehman

    2011-01-01

    Full Text Available Noise-Induced Hearing Loss (NIHL has become a major source of health problem in industrial workers due to continuous exposure to high frequency sounds emitting from the machines. In the past, several studies have been carried-out to identify NIHL industrial workers. Unfortunately, these studies neglected some important factors that directly affect hearing ability in human. Artificial Neural Network (ANN provides very effective way to predict hearing loss in humans. However, the training process for an ANN required the designers to arbitrarily select parameters such as network topology, initial weights and biases, learning rate value, the activation function, value for gain in activation function and momentum. An improper choice of any of these parameters can result in slow convergence or even network paralysis, where the training process comes to a standstill or get stuck at local minima. Therefore, this current study focuses on proposing a new framework on using Gradient Descent Back Propagation Neural Network model with an improvement on the momentum value to identify the important factors that directly affect the hearing ability of industrial workers. Results from the prediction will be used in determining the environmental health hazards which affect the workers health.

  8. Noise analysis and single-channel observations of 4 pS chloride channels in human airway epithelia.

    OpenAIRE

    Duszyk, M; French, A S; Man, S F

    1992-01-01

    Apical membranes of human airway epithelial cells have significant chloride permeability, which is reduced in cystic fibrosis (CF), causing abnormal electrochemistry and impaired mucociliary clearance. At least four types of chloride channels have been identified in these cells, but their relative roles in total permeability and CF are unclear. Noise analysis was used to measure the conductance of chloride channels in human nasal epithelial cells. The data indicate that channels with a mean c...

  9. Noise suppression by noise

    OpenAIRE

    Vilar, J. M. G.; Rubí Capaceti, José Miguel

    2001-01-01

    We have analyzed the interplay between an externally added noise and the intrinsic noise of systems that relax fast towards a stationary state, and found that increasing the intensity of the external noise can reduce the total noise of the system. We have established a general criterion for the appearance of this phenomenon and discussed two examples in detail.

  10. The Influence of High-Frequency Envelope Information on Low-Frequency Vowel Identification in Noise.

    Directory of Open Access Journals (Sweden)

    Wiebke Schubotz

    Full Text Available Vowel identification in noise using consonant-vowel-consonant (CVC logatomes was used to investigate a possible interplay of speech information from different frequency regions. It was hypothesized that the periodicity conveyed by the temporal envelope of a high frequency stimulus can enhance the use of the information carried by auditory channels in the low-frequency region that share the same periodicity. It was further hypothesized that this acts as a strobe-like mechanism and would increase the signal-to-noise ratio for the voiced parts of the CVCs. In a first experiment, different high-frequency cues were provided to test this hypothesis, whereas a second experiment examined more closely the role of amplitude modulations and intact phase information within the high-frequency region (4-8 kHz. CVCs were either natural or vocoded speech (both limited to a low-pass cutoff-frequency of 2.5 kHz and were presented in stationary 3-kHz low-pass filtered masking noise. The experimental results did not support the hypothesized use of periodicity information for aiding low-frequency perception.

  11. Mitigating Insider Threat Using Human Behavior Influence Models

    Science.gov (United States)

    2006-06-01

    Change in Score Versus Time for Both Employees (over 3 years).......................94 45. Distribution of Sensitivity Tests Performed ...Human Behavior Human Behavior is defined as a “collection of activities performed by human beings and influenced by culture, attitudes, emotions...values, ethics, authority, rapport, hypnosis , persuasion, and/or coercion.” [6] The theory behind human behavior is humans react to “definite objective

  12. Identifying human influences on atmospheric temperature.

    Science.gov (United States)

    Santer, Benjamin D; Painter, Jeffrey F; Mears, Carl A; Doutriaux, Charles; Caldwell, Peter; Arblaster, Julie M; Cameron-Smith, Philip J; Gillett, Nathan P; Gleckler, Peter J; Lanzante, John; Perlwitz, Judith; Solomon, Susan; Stott, Peter A; Taylor, Karl E; Terray, Laurent; Thorne, Peter W; Wehner, Michael F; Wentz, Frank J; Wigley, Tom M L; Wilcox, Laura J; Zou, Cheng-Zhi

    2013-01-02

    We perform a multimodel detection and attribution study with climate model simulation output and satellite-based measurements of tropospheric and stratospheric temperature change. We use simulation output from 20 climate models participating in phase 5 of the Coupled Model Intercomparison Project. This multimodel archive provides estimates of the signal pattern in response to combined anthropogenic and natural external forcing (the fingerprint) and the noise of internally generated variability. Using these estimates, we calculate signal-to-noise (S/N) ratios to quantify the strength of the fingerprint in the observations relative to fingerprint strength in natural climate noise. For changes in lower stratospheric temperature between 1979 and 2011, S/N ratios vary from 26 to 36, depending on the choice of observational dataset. In the lower troposphere, the fingerprint strength in observations is smaller, but S/N ratios are still significant at the 1% level or better, and range from three to eight. We find no evidence that these ratios are spuriously inflated by model variability errors. After removing all global mean signals, model fingerprints remain identifiable in 70% of the tests involving tropospheric temperature changes. Despite such agreement in the large-scale features of model and observed geographical patterns of atmospheric temperature change, most models do not replicate the size of the observed changes. On average, the models analyzed underestimate the observed cooling of the lower stratosphere and overestimate the warming of the troposphere. Although the precise causes of such differences are unclear, model biases in lower stratospheric temperature trends are likely to be reduced by more realistic treatment of stratospheric ozone depletion and volcanic aerosol forcing.

  13. White noise and synchronization shaping the age structure of the human population

    Science.gov (United States)

    Cebrat, Stanislaw; Biecek, Przemyslaw; Bonkowska, Katarzyna; Kula, Mateusz

    2007-06-01

    We have modified the standard diploid Penna model of ageing in such a way that instead of threshold of defective loci resulting in genetic death of individuals, the fluctuation of environment and "personal" fluctuations of individuals were introduced. The sum of the both fluctuations describes the health status of the individual. While environmental fluctuations are the same for all individuals in the population, the personal component of fluctuations is composed of fluctuations corresponding to each physiological function (gene, genetic locus). It is rather accepted hypothesis that physiological parameters of any organism fluctuate highly nonlinearly. Transition to the synchronized behaviors could be a very strong diagnostic signal of the life threatening disorder. Thus, in our model, mutations of genes change the chaotic fluctuations representing the function of a wild gene to the synchronized signals generated by mutated genes. Genes are switched on chronologically, like in the standard Penna model. Accumulation of defective genes predicted by Medawar's theory of ageing leads to the replacement of uncorrelated white noise corresponding to the healthy organism by the correlated signals of defective functions. As a result we have got the age distribution of population corresponding to the human demographic data.

  14. Random genetic drift, natural selection, and noise in human cranial evolution.

    Science.gov (United States)

    Roseman, Charles C

    2016-08-01

    This study assesses the extent to which relationships among groups complicate comparative studies of adaptation in recent human cranial variation and the extent to which departures from neutral additive models of evolution hinder the reconstruction of population relationships among groups using cranial morphology. Using a maximum likelihood evolutionary model fitting approach and a mixed population genomic and cranial data set, I evaluate the relative fits of several widely used models of human cranial evolution. Moreover, I compare the goodness of fit of models of cranial evolution constrained by genomic variation to test hypotheses about population specific departures from neutrality. Models from population genomics are much better fits to cranial variation than are traditional models from comparative human biology. There is not enough evolutionary information in the cranium to reconstruct much of recent human evolution but the influence of population history on cranial variation is strong enough to cause comparative studies of adaptation serious difficulties. Deviations from a model of random genetic drift along a tree-like population history show the importance of environmental effects, gene flow, and/or natural selection on human cranial variation. Moreover, there is a strong signal of the effect of natural selection or an environmental factor on a group of humans from Siberia. The evolution of the human cranium is complex and no one evolutionary process has prevailed at the expense of all others. A holistic unification of phenome, genome, and environmental context, gives us a strong point of purchase on these problems, which is unavailable to any one traditional approach alone. Am J Phys Anthropol 160:582-592, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  15. Influencing Factors of Rural Human Consumption in China

    Directory of Open Access Journals (Sweden)

    Jun LI

    2014-12-01

    Full Text Available The paper combines the social capital theory, the ordered choice model, and the case study in order to analyze the influence factors of the rural human consumption. The results show the presence of inverted U shape curve relation between human consumption amount and age. Human communication range, income, the highest single human consumption amount and the minimum amount, occupation, family population, the existing of human consumption capacity and the scope of the existing relationships between interpersonal relationship satisfaction and other factors on human consumption level has positive influence on human consumption level. Domestic researches on human behaviour are wide, but most of the studies are focused on the social, human, and psychological disciplines. For the origin of human consumption, scholars focus on four aspects like novelty, human or mutual needs. This research is based on field investigation conducted in Niuxintai village, Liaoning Province, in order to understand the current situation of the rural human consumption in China, and to explain the function and influencing factors of human consumption.

  16. Influence of Workforce Ageing on Human Capital Formation

    OpenAIRE

    Stonawski, M.

    2008-01-01

    This paper addresses the question of how workforce ageing influences human capital formation, human capital deterioration, and future productivity growth. The method presented in this paper focuses on the magnitude of human capital that has been accumulated in an individual. It takes into consideration education, acquiring knowledge and experience, knowledge becoming obsolete or forgotten, as well as the impact of health. The estimated human capital curve (based on the net effect of the vario...

  17. Tire-road noise: an experimental study of tire and road design parameters

    NARCIS (Netherlands)

    Bekke, Dirk; Wijnant, Ysbrand; Weegerink, Thijs; Boer, de Andre

    2013-01-01

    It is widely known that road traffic noise has negative influences on human health. Hence, as tire-road noise is considered to be the most dominant cause of road traffic noise above 30-50 km/h, a lot of research is performed by the two involving industries: road authorities/manufacturers and tire ma

  18. Tire-road noise: an experimental study of tire and road design parameters

    NARCIS (Netherlands)

    Bekke, Dirk; Wijnant, Ysbrand H.; Weegerink, Thijs; de Boer, Andries

    2013-01-01

    It is widely known that road traffic noise has negative influences on human health. Hence, as tire-road noise is considered to be the most dominant cause of road traffic noise above 30-50 km/h, a lot of research is performed by the two involving industries: road authorities/manufacturers and tire

  19. Influence of human behavior on cholera dynamics.

    Science.gov (United States)

    Wang, Xueying; Gao, Daozhou; Wang, Jin

    2015-09-01

    This paper is devoted to studying the impact of human behavior on cholera infection. We start with a cholera ordinary differential equation (ODE) model that incorporates human behavior via modeling disease prevalence dependent contact rates for direct and indirect transmissions and infectious host shedding. Local and global dynamics of the model are analyzed with respect to the basic reproduction number. We then extend the ODE model to a reaction-convection-diffusion partial differential equation (PDE) model that accounts for the movement of both human hosts and bacteria. Particularly, we investigate the cholera spreading speed by analyzing the traveling wave solutions of the PDE model, and disease threshold dynamics by numerically evaluating the basic reproduction number of the PDE model. Our results show that human behavior can reduce (a) the endemic and epidemic levels, (b) cholera spreading speeds and (c) the risk of infection (characterized by the basic reproduction number). Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  20. Influence of human behavior on cholera dynamics

    OpenAIRE

    Wang, Xueying; Gao, Daozhou; Wang, Jin

    2015-01-01

    This paper is devoted to studying the impact of human behavior on cholera infection. We start with a cholera ordinary differential equation (ODE) model that incorporates human behavior via modeling disease prevalence dependent contact rates for direct and indirect transmissions and infectious host shedding. Local and global dynamics of the model are analyzed with respect to the basic reproduction number. We then extend the ODE model to a reaction-convection-diffusion partial differential equa...

  1. Influence of measurement noise on the PSO based localization of an impact occurring on elastic plates

    Directory of Open Access Journals (Sweden)

    El-Bakari A.

    2014-01-01

    Full Text Available This paper presents the application of particle swarm optimization algorithm to reconstruct the characteristics of impacts occurring on homogeneous and isotropic elastic plates and which cannot be reduced to a concentrated force. Solution of this inverse problem was achieved through minimizing a fitness function defined in terms of the root mean square error between the measured and the calculated responses. This included information provided by numerous sensors. The impacting force was assumed to result from uniformly distributed pressure acting over a rectangular patch. Use was made of the reciprocity theorem to decouple the localization problem from the deconvolution part intended to reconstruct the pressure time signal. The particle swarm optimization based model was found to be highly efficient in finding the impact zone location. Focus was done on the robustness aspect of force impact localization when an additive white noise is assumed to perturb response measurements.

  2. An overview of health effects on noise

    Science.gov (United States)

    Osada, Y.

    1988-12-01

    Although noise can damage the inner ear and cause other pathological changes, its most common negative effects are non-somatic, such as a perception of noisiness and disturbance of daily activities. According to the definition of health by WHO, this should be considered as a health hazard. These health effects of noise can be classified into the following three categories: (I) hearing loss, perception of noisiness and masking are produced along the auditory pathway and are thus direct and specific effects of noise; (II) interference with performance, rest and sleep, a feeling of discomfort and some physiological effects are produced as indirect and non-specific effects via reticular formation of the midbrain; (III) annoyance is not merely a feeling of unpleasantness but the feeling of being bothered or troubled, and includes the development of a particular attitude toward the noise source. Individual or group behavioral responses will be evoked when annoyance develops. Annoyance and behavioral response are integrated and composite effects. The health effects of noise are modified by many factors related to both the noise and the individual. Noise level, frequency spectrum, duration and impulsiveness modify the effects. Sex, age, health status and mental character also have an influence on the effects. Direct effects of noise are most dependent on the physical nature of the noise and least dependent on human factors. Indirect effects are more dependent, and integrated effects most dependent, on human factors.

  3. ABOUT TRACK CIRCUIT CALCULATION METHOD DEPENDENT ON FERROMAGNET PROPERTIES IN CONDITIONS OF TRACTION CURRENT NOISE INFLUENCE

    Directory of Open Access Journals (Sweden)

    A. Yu. Zhuravlev

    2016-02-01

    Full Text Available Purpose. The work is intended to investigate the electromagnetic processes in impedance bond in order to improve noise immunity of track circuits (TC for safe railway operation. Methodology. To achieve this purpose the methods of scientific analysis, mathematical modelling, experimental study, a large-scale simulation were used. Findings. The work examined the interference affecting the normal performance of track circuits. To a large extent, part of track circuit damages account for failures in track circuit equipment. Track circuit equipment is connected directly to the track line susceptible to traction current interference, which causes changes in its electrical characteristics and electromagnetic properties. Normal operability, performance of the main operating modes of the track circuit is determined by previous calculation of its performance and compilation of regulatory tables. The classical method for determination of track circuit parameters was analysed. The classical calculation method assumes representation of individual sections of the electrical track circuit using the quadripole network with known coefficients, usually in the A-form. Determining the coefficients of linear element circuit creates no metrological or mathematical difficulties. However, in circuits containing nonlinear ferromagnets (FM, obtaining the coefficients on the entire induction change range in the cores is quite a difficult task because the classical methods of idling (I and short circuit (SC are not acceptable. This leads to complicated methods for determining both the module and the arguments of quadripole network coefficients. Instead of the classical method, the work proposed the method for calculating the track circuit dependent on nonlinear properties of ferromagnets. Originality. The article examines a new approach to the calculation of TC taking into account the losses in ferromagnets (FM, without determination of equivalent circuit quadripole

  4. Human influences on evolution, and the ecological and societal consequences

    Science.gov (United States)

    Hendry, Andrew P.; Svensson, Erik I.

    2017-01-01

    Humans have dramatic, diverse and far-reaching influences on the evolution of other organisms. Numerous examples of this human-induced contemporary evolution have been reported in a number of ‘contexts’, including hunting, harvesting, fishing, agriculture, medicine, climate change, pollution, eutrophication, urbanization, habitat fragmentation, biological invasions and emerging/disappearing diseases. Although numerous papers, journal special issues and books have addressed each of these contexts individually, the time has come to consider them together and thereby seek important similarities and differences. The goal of this special issue, and this introductory paper, is to promote and expand this nascent integration. We first develop predictions as to which human contexts might cause the strongest and most consistent directional selection, the greatest changes in evolutionary potential, the greatest genetic (as opposed to plastic) changes and the greatest effects on evolutionary diversification. We then develop predictions as to the contexts where human-induced evolutionary changes might have the strongest effects on the population dynamics of the focal evolving species, the structure of their communities, the functions of their ecosystems and the benefits and costs for human societies. These qualitative predictions are intended as a rallying point for broader and more detailed future discussions of how human influences shape evolution, and how that evolution then influences species traits, biodiversity, ecosystems and humans. This article is part of the themed issue ‘Human influences on evolution, and the ecological and societal consequences’. PMID:27920373

  5. Signals and noise in the octavolateralis systems: what is the impact of human activities on fish sensory function?

    Science.gov (United States)

    Braun, Christopher B

    2015-01-01

    The octavolateralis systems of fishes include the vestibular, auditory, lateral line and electrosensory systems. They are united by common developmental and neuro-computational features, including hair cell sensors and computations based on cross-neuron analyses of differential hair cell stimulation patterns. These systems also all use both spectral and temporal filters to separate signals from each other and from noise, and the distributed senses (lateral line and electroreception) add spatial filters as well. Like all sensory systems, these sensors must provide the animal with guidance for adaptive behavior within a sensory scene composed of multiple stimuli and varying levels of ambient noise, including that created by human activities. In the extreme, anthropogenic activities impact the octavolateralis systems by destroying or degrading the habitats that provide ecological resources and sensory inputs. At slightly lesser levels of effect, anthropogenic pollutants can be damaging to fish tissues, with sensory organs often the most vulnerable. The exposed sensory cells of the lateral line and electrosensory systems are especially sensitive to aquatic pollution. At still lesser levels of impact, anthropogenic activities can act as both acute and chronic stressors, activating hormonal changes that may affect behavioral and sensory function. Finally, human activities are now a nearly ubiquitous presence in aquatic habitats, often with no obvious effects on the animals exposed to them. Ship noise, indigenous and industrial fishing techniques, and all the ancillary noises of human civilization form a major part of the soundscape of fishes. How fish use these new sources of information about their habitat is a new and burgeoning field of study. © 2014 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

  6. Adaptive Noise Reduction System

    Directory of Open Access Journals (Sweden)

    Ivana Ropuš

    2013-01-01

    Full Text Available Noise is an all-present environment pollutant, considered to be one of the greatest contemporary pollutants. World-wide, co-ordinated actions are conducted in order to develop systems which minimise the noise influence onto society.In this article we argue that novel approach to suppression of influence of noise is useful. Furthermore, we argue that the efficient approach is formulation of the efficient, broadly applicable, ubiquituous, adaptive noise-protection system. The approach combines the natural noise-protection form based on plants with the artificially formed coatings.Elements of the system are discussed, its formation and maintenance analysed and perspectives conjectured.

  7. Influence of x-ray energy spectrum, contrasting detail and detector on the signal-to-noise ratio (SNR) and detective quantum efficiency (DQE) in projection radiography

    Energy Technology Data Exchange (ETDEWEB)

    Sandborg, Michael; Carlsson, G.A. (Linkoeping Univ. (Sweden). Dept. of Radiation Physics)

    1992-06-01

    A lower limit to patient irradiation in diagnostic radiology is set by the fundamental stochastics of the energy imparted to the image receptor (quantum noise). Image quality is investigated here and expressed in terms of the signal-to-noise ratio due to quantum noise. The Monte Carlo method is used to calculate signal-to-noise ratios (SNR{sub {Delta}S}) and detective quantum efficiencies (DQE{sub {Delta}S}) in imaging thin contrasting details of air, fat, bone and iodine within a water phantom using x-ray spectra (40-140 kV) and detectors of CsI, BaFCl and Gd{sub 2}O{sub 2}S. The atomic composition of the contrasting detail influences considerably the values of SNR{sub {Delta}S} due to the different modulations of the energy spectra of primary photons passing beside and through the contrasting detail. (author).

  8. Introductory guide to noise

    CSIR Research Space (South Africa)

    Ferreira, T.M

    1973-01-01

    Full Text Available The difference between sound and noise varies from one human being to another. Noise, then, is simply unwanted sound and to understand how it can be combatted we must know more about its nature. A guide of acceptable levels of noise are investigated....

  9. Influence of sociodemographics on human mobility

    Science.gov (United States)

    Lenormand, Maxime; Louail, Thomas; Cantú-Ros, Oliva G.; Picornell, Miguel; Herranz, Ricardo; Arias, Juan Murillo; Barthelemy, Marc; Miguel, Maxi San; Ramasco, José J.

    2015-05-01

    Human mobility has been traditionally studied using surveys that deliver snapshots of population displacement patterns. The growing accessibility to ICT information from portable digital media has recently opened the possibility of exploring human behavior at high spatio-temporal resolutions. Mobile phone records, geolocated tweets, check-ins from Foursquare or geotagged photos, have contributed to this purpose at different scales, from cities to countries, in different world areas. Many previous works lacked, however, details on the individuals’ attributes such as age or gender. In this work, we analyze credit-card records from Barcelona and Madrid and by examining the geolocated credit-card transactions of individuals living in the two provinces, we find that the mobility patterns vary according to gender, age and occupation. Differences in distance traveled and travel purpose are observed between younger and older people, but, curiously, either between males and females of similar age. While mobility displays some generic features, here we show that sociodemographic characteristics play a relevant role and must be taken into account for mobility and epidemiological modelization.

  10. Fingertip contact influences human postural control

    Science.gov (United States)

    Jeka, J. J.; Lackner, J. R.

    1994-01-01

    Touch and pressure stimulation of the body surface can strongly influence apparent body orientation, as well as the maintenance of upright posture during quiet stance. In the present study, we investigated the relationship between postural sway and contact forces at the fingertip while subjects touched a rigid metal bar. Subjects were tested in the tandem Romberg stance with eyes open or closed under three conditions of fingertip contact: no contact, touch contact (postural sway when compared to the no contact, eyes closed condition. Body sway and fingertip forces were essentially in phase with force contact, suggesting that fingertip contact forces are physically counteracting body sway. Time delays between body sway and fingertip forces were much larger with light touch contact, suggesting that the fingertip is providing information that allows anticipatory innervation of musculature to reduce body sway. The results are related to observations on precision grip as well as the somatosensory, proprioceptive, and motor mechanisms involved in the reduction of body sway.

  11. Human Auditory Communication Disturbances Due To Road Traffic Noise Pollution in Calabar City, Nigeria

    Directory of Open Access Journals (Sweden)

    E. O. Obisung

    2016-10-01

    Full Text Available Study on auditory communication disturbances due to road transportation noise in Calabar Urban City, Nigeria was carried out. Both subjective (psycho-social and objective (acoustical measurements were made for a period of twelve months. Questionnaire/interview schedules containing pertinent questions were administered randomly to 500 respondents of age 15 year and above, who were also with a good level of literacy skills (reading writing and leaving in houses sited along or parallel to busy road, with heavy traffic volume for at least three (3 years. The questionnaires provided the psycho-social responses of respondents used in this study, their reactions to road traffic noise effect on communication activities (listening to radio, listening and watching television, verbal communication between individuals, speech communication and telephone/GSM communication. Acoustical measurements were made at the facades of respondents' houses facing the road using precision digital sound level meter, Bruel and Kjaer (B & K type 732 following ISO standards 1996. The meter read the road traffic noise levels at measurement sites (facades of respondents' houses. From the results obtained in this study residents of Calabar City suffer serious communication interferences as a result of excessive road traffic noise levels. The noise indices used for this study were LAeq and Ldn. Noise levels obtained were over 93 dB(A (daytime and 60 dB(A, (nighttime for LAeq and 80 dB(A for Ldn. These far exceeded the recommended theoretical values of 45-55 and 70 dB(A, for LAeqand Ldn respectively. A-weighted sound pressure level (SPLS range between 87.0 and 100.0 dB(A. In this study it was also observed that over 98% of the respondents reported their television watching/radio listening disturbed, 99% recorded telephone/GSM disturbed, and 98% reported face-to-face verbal conversation disturbed, and 98% reported speech communication disturbed. The background noise levels (BNLs of

  12. On the Origin of the 1,000 Hz Peak in the Spectrum of the Human Tympanic Electrical Noise

    Directory of Open Access Journals (Sweden)

    Javiera Pardo-Jadue

    2017-07-01

    Full Text Available The spectral analysis of the spontaneous activity recorded with an electrode positioned near the round window of the guinea pig cochlea shows a broad energy peak between 800 and 1,000 Hz. This spontaneous electric activity is called round window noise or ensemble background activity. In guinea pigs, the proposed origin of this peak is the random sum of the extracellular field potentials generated by action potentials of auditory nerve neurons. In this study, we used a non-invasive method to record the tympanic electric noise (TEN in humans by means of a tympanic wick electrode. We recorded a total of 24 volunteers, under silent conditions or in response to stimuli of different modalities, including auditory, vestibular, and motor activity. Our results show a reliable peak of spontaneous activity at ~1,000 Hz in all studied subjects. In addition, we found stimulus-driven responses with broad-band noise that in most subjects produced an increase in the magnitude of the energy band around 1,000 Hz (between 650 and 1,200 Hz. Our results with the vestibular stimulation were not conclusive, as we found responses with all caloric stimuli, including 37°C. No responses were observed with motor tasks, like eye movements or blinking. We demonstrate the feasibility of recording neural activity from the electric noise of the tympanic membrane with a non-invasive method. From our results, we suggest that the 1,000 Hz component of the TEN has a mixed origin including peripheral and central auditory pathways. This research opens up the possibility of future clinical non-invasive techniques for the functional study of auditory and vestibular nerves in humans.

  13. Influence Factors of Audible Noise Caused by Corona Discharge on UHVDC Transmission Lines Under High Altitude Condition

    Institute of Scientific and Technical Information of China (English)

    TIAN Feng; YU Zhanqing; ZENG Rong; LIU Lei; LI Min; LI Ruihai

    2012-01-01

    Audible noises (AN) generated by corona discharges on ultra high voltage direct current (UHVDC) transmission lines is one of the key issues of UHVDC power projects. Experimental results were obtained synchronously by 10 Briiel & Kjeer outdoor AN instruments under the full-scale test lines in National Laboratory for UHV Technology in Kunming at an altitude of 2 100 m. Long-term statistical measurements of the AN level were performed almost 24 hours a day and 5 ~ 6 days a week in 2 years. Influences of voltage, line configurations, temperature and humidity on the characteristics of AN levels were analysed. The measurement results show that the AN level rises with increasing line voltage, decreasing minimum conductor height and increasing bundle radius. The pole spacing has no significant influence on the peak value of the AN level. The AN level varies about _+ 1 dB in the temperature range of 15~22℃, and no more than ±2 dB within 6.8~24.4 ℃. The results also indicate that in a relative low range of absolute humidity, about 5 ~ 7. 99 g/ma, the AN level fluctuates slightly at different measurement points. However, in a relative high absolute humidity range, about 8 ~ 11. 5 g/ma, the AN level decreases with the increase of absolute humidity.

  14. Investigation of a glottal related harmonics-to-noise ratio and spectral tilt as indicators of glottal noise in synthesized and human voice signals.

    LENUS (Irish Health Repository)

    Murphy, Peter J

    2008-03-01

    The harmonics-to-noise ratio (HNR) of the voiced speech signal has implicitly been used to infer information regarding the turbulent noise level at the glottis. However, two problems exist for inferring glottal noise attributes from the HNR of the speech wave form: (i) the measure is fundamental frequency (f0) dependent for equal levels of glottal noise, and (ii) any deviation from signal periodicity affects the ratio, not just turbulent noise. An alternative harmonics-to-noise ratio formulation [glottal related HNR (GHNR\\')] is proposed to overcome the former problem. In GHNR\\' a mean over the spectral range of interest of the HNRs at specific harmonic\\/between-harmonic frequencies (expressed in linear scale) is calculated. For the latter issue [(ii)] two spectral tilt measures are shown, using synthesis data, to be sensitive to glottal noise while at the same time being comparatively insensitive to other glottal aperiodicities. The theoretical development predicts that the spectral tilt measures reduce as noise levels increase. A conventional HNR estimator, GHNR\\' and two spectral tilt measures are applied to a data set of 13 pathological and 12 normal voice samples. One of the tilt measures and GHNR\\' are shown to provide statistically significant differentiating power over a conventional HNR estimator.

  15. Influence of strong noise on the decline and propagation of population in the delayed Malthus-Verhulst model

    Science.gov (United States)

    Cai, Jian-Chun; Mei, Dong-Cheng

    2010-11-01

    The effects of strong noise on the decline and propagation processes of a population in the Malthus-Verhulst model with time delay are investigated by a stochastic simulation. Time delays in two different processes are concurrent in ecosystems. The simulation results indicate that: The stability of the population is enhanced by the decreasing multiplicative noise intensity and the increasing delay time. The replacement of old individuals with young ones is accelerated by an increasing multiplicative noise intensity, an increasing additive noise intensity and a decreasing delay time. An increasing multiplicative noise intensity will drive the population of species to fluctuate more largely.

  16. Robustness of intrinsic connectivity networks in the human brain to the presence of acoustic scanner noise

    NARCIS (Netherlands)

    Langers, Dave R. M.; van Dijk, Pim

    2011-01-01

    Evoked responses in functional magnetic resonance imaging (fMRI) are affected by the presence of acoustic scanner noise (ASN). Particularly, stimulus-related activation of the auditory system and deactivation of the default mode network have repeatedly been shown to diminish. In contrast, little is

  17. Some remarks on the effects of drugs, lack of sleep and loud noise on human performance.

    NARCIS (Netherlands)

    Sanders, A.F. & A.A. Bunt.

    1971-01-01

    Some literature is reviewed on the effect of some drugs, (amphetamine, hypnotics, alcohol), loud noise and sleep loss in test of time estimation, decision making, long term performance and short term memory. Results are most clear with respect to amphetamine, hypnotics and lack of sleep, in that amp

  18. Some remarks on the effects of drugs, lack of sleep and loud noise on human performance.

    NARCIS (Netherlands)

    Sanders, A.F. & A.A. Bunt.

    1971-01-01

    Some literature is reviewed on the effect of some drugs, (amphetamine, hypnotics, alcohol), loud noise and sleep loss in test of time estimation, decision making, long term performance and short term memory. Results are most clear with respect to amphetamine, hypnotics and lack of sleep, in that

  19. What is the influence of background noise and exercise on the listening levels of iPod users?

    Science.gov (United States)

    Hodgetts, William; Szarko, Ryan; Rieger, Jana

    2009-12-01

    The widespread use of portable listening devices (PLDs) has increased concern about the potential for hearing impairment caused by their use. The current study investigated the effects of external noise and exercise on the use of PLDs. The 24 participants listened to the same song on an iPod during rest-in-quiet, rest-in-noise, and exercise-in-noise conditions. Preferred listening levels (PLLs) were recorded and participants' maximum noise doses were calculated. Participants selected significantly higher listening levels in both noise conditions than in the quiet condition. The variability of volume selection was reduced significantly in the noise conditions. The maximum daily noise dose would have been exceeded by seven participants in the rest-in-noise condition and by eight in the exercise-in-noise condition compared to one participant in the rest-in-quiet condition. These results indicated that increased background noise causes individuals to increase the volume on their PLDs to potentially dangerous levels and that increased noise alone was not the only factor affecting the participants as the addition of exercise induced even further increases in PLLs.

  20. Experimental study of traffic noise and human response in an urban area: Deviations from standard annoyance predictions

    NARCIS (Netherlands)

    Salomons, E.M.; Janssen, S.A.; Verhagen, H.L.M.; Wessels, P.W.

    2014-01-01

    Annoyance and sleep disturbance by road and rail traffic noise in an urban area are investigated. Noise levels Lden and Lnight are determined with an engineering noise model that is optimized for the local situation, based on local noise measurements. The noise levels are combined with responses of

  1. Lifestyle influences human sperm functional quality

    Institute of Scientific and Technical Information of China (English)

    Mnica Ferreira; Joana Vieira Silva; Vladimiro Silva; Antnio Barros; Margarida Fardilha

    2012-01-01

    Objective:To investigate the impact of acute lifestyle changes on human sperm functional quality.Methods:In the academic festivities week, young and apparently healthy male students who voluntarily submit themselves to acute lifestyle alterations(among the potentially important variations are increase in alcohol, caffeine, and tobacco consumption and circadian rhythm shifts) were used as a model system.Sperm samples were obtained before and after the academic week and compared by traditional semen analysis(n=54) and also tested for cleavedPolyADP-ribose polymerase(PARP) protein, an apoptotic marker(n=35).Results:Acute lifestyle changes that occurred during the academic week festivities(the study model) resulted both in a significant reduction in sperm quality, assessed by basic semen analysis(decrease in sperm concentration, total number of spermatozoa, progressive and non-progressive motility and increase in sperm morphological abnormalities) and by an increase in the expression of the apoptotic marker, cleavedPARP, in the ejaculate.Conclusions:Acute lifestyle changes have clear deleterious effects on sperm quality.We propose cleavedPARP as a novel molecular marker, valuable for assessing spermquality in parallel with the basic semen analysis method.

  2. Can Helicobacter pylori infection influence human reproduction?

    Science.gov (United States)

    Moretti, Elena; Figura, Natale; Collodel, Giulia; Ponzetto, Antonio

    2014-05-21

    Helicobacter pylori (H. pylori) infection could be associated with extra-digestive diseases. Here, we report the evidences concerning the decrease in reproductive potential occurring in individuals infected by H. pylori, especially by strains expressing CagA. This infection is more prevalent in individuals with fertility disorders. Infected women have anti-H. pylori antibodies in cervical mucus and follicular fluid that may decrease sperm motility and cross react immunologically with spermatozoa, conceivably hampering the oocyte/sperm fusion. Infection by CagA positive organisms enhances the risk of preeclampsia, which is a main cause of foetus death. These findings are supported by the results of experimental infections of pregnant mice, which may cause reabsorption of a high number of foetuses and alter the balance between Th1 and Th2 cell response. Infected men have decreased sperm motility, viability and numbers of normally shaped sperm and augmented systemic levels of inflammatory cytokines, such as tumor necrosis factor-α, which may damage spermatozoa. In countries where parasitic infestation is endemic, detrimental effects of infection upon spermatozoa may not occur, because the immune response to parasites could determine a switch from a predominant Th1 type to Th2 type lymphocytes, with production of anti-inflammatory cytokines. In conclusion, the evidences gathered until now should be taken into consideration for future studies aiming to explore the possible role of H. pylori infection on human reproduction.

  3. Criteria for environmental noise assessment

    OpenAIRE

    Hadzi-Nikolova, Marija; Mirakovski, Dejan; Doneva, Nikolinka

    2015-01-01

    The noise assessment generally refers to the assessment of noise impact from a specific source, such as noise originating from certain industrial plants, road traffic, and this is not always an easy task. Practically in every surrounding, a number of different sources contribute to the ambiental noise at a certain point. Standardization of noise level includes recommendations for noise level prescribed by legislation, which are enabling stay in the environment without danger to human heal...

  4. Dopamine Activation Preserves Visual Motion Perception Despite Noise Interference of Human V5/MT

    Science.gov (United States)

    Yousif, Nada; Fu, Richard Z.; Abou-El-Ela Bourquin, Bilal; Bhrugubanda, Vamsee; Schultz, Simon R.

    2016-01-01

    When processing sensory signals, the brain must account for noise, both noise in the stimulus and that arising from within its own neuronal circuitry. Dopamine receptor activation is known to enhance both visual cortical signal-to-noise-ratio (SNR) and visual perceptual performance; however, it is unknown whether these two dopamine-mediated phenomena are linked. To assess this, we used single-pulse transcranial magnetic stimulation (TMS) applied to visual cortical area V5/MT to reduce the SNR focally and thus disrupt visual motion discrimination performance to visual targets located in the same retinotopic space. The hypothesis that dopamine receptor activation enhances perceptual performance by improving cortical SNR predicts that dopamine activation should antagonize TMS disruption of visual perception. We assessed this hypothesis via a double-blinded, placebo-controlled study with the dopamine receptor agonists cabergoline (a D2 agonist) and pergolide (a D1/D2 agonist) administered in separate sessions (separated by 2 weeks) in 12 healthy volunteers in a William's balance-order design. TMS degraded visual motion perception when the evoked phosphene and the visual stimulus overlapped in time and space in the placebo and cabergoline conditions, but not in the pergolide condition. This suggests that dopamine D1 or combined D1 and D2 receptor activation enhances cortical SNR to boost perceptual performance. That local visual cortical excitability was unchanged across drug conditions suggests the involvement of long-range intracortical interactions in this D1 effect. Because increased internal noise (and thus lower SNR) can impair visual perceptual learning, improving visual cortical SNR via D1/D2 agonist therapy may be useful in boosting rehabilitation programs involving visual perceptual training. SIGNIFICANCE STATEMENT In this study, we address the issue of whether dopamine activation improves visual perception despite increasing sensory noise in the visual cortex

  5. Reexamining the evidence for a pitch-sensitive region: a human fMRI study using iterated ripple noise.

    Science.gov (United States)

    Barker, Daphne; Plack, Christopher J; Hall, Deborah A

    2012-04-01

    Human neuroimaging studies have identified a region of auditory cortex, lateral Heschl's gyrus (HG), that shows a greater response to iterated ripple noise (IRN) than to a Gaussian noise control. Based in part on results using IRN as a pitch-evoking stimulus, it has been argued that lateral HG is a general "pitch center." However, IRN contains slowly varying spectrotemporal modulations, unrelated to pitch, that are not found in the control stimulus. Hence, it is possible that the cortical response to IRN is driven in part by these modulations. The current study reports the first attempt to control for these modulations. This was achieved using a novel type of stimulus that was generated by processing IRN to remove the fine temporal structure (and thus the pitch) but leave the slowly varying modulations. This "no-pitch IRN" stimulus is referred to as IRNo. Results showed a widespread response to the spectrotemporal modulations across auditory cortex. When IRN was contrasted with IRNo rather than with Gaussian noise, the apparent effect of pitch was no longer statistically significant. Our findings raise the possibility that a cortical response unrelated to pitch could previously have been errantly attributed to pitch coding.

  6. Influence of age, irradiation and humanization on NSG mouse phenotypes

    Directory of Open Access Journals (Sweden)

    Jaclyn S. Knibbe-Hollinger

    2015-10-01

    Full Text Available Humanized mice are frequently utilized in bench to bedside therapeutic tests to combat human infectious, cancerous and degenerative diseases. For the fields of hematology-oncology, regenerative medicine, and infectious diseases, the immune deficient mice have been used commonly in basic research efforts. Obstacles in true translational efforts abound, as the relationship between mouse and human cells in disease pathogenesis and therapeutic studies requires lengthy investigations. The interplay between human immunity and mouse biology proves ever more complicated when aging, irradiation, and human immune reconstitution are considered. All can affect a range of biochemical and behavioral functions. To such ends, we show age- and irradiation-dependent influences for the development of macrocytic hyper chromic anemia, myelodysplasia, blood protein reductions and body composition changes. Humanization contributes to hematologic abnormalities. Home cage behavior revealed day and dark cycle locomotion also influenced by human cell reconstitutions. Significant age-related day-to-day variability in movement, feeding and drinking behaviors were observed. We posit that this data serves to enable researchers to better design translational studies in this rapidly emerging field of mouse humanization.

  7. The influence of hologram aperture on speckle noise in the reconstructed image of digital holography and its reduction

    Science.gov (United States)

    Cai, Xiao-ou; Wang, Hui

    2008-01-01

    Based on the whole process of the recording and reconstruction of digital holography, we study the formation cause of speckle noise in its reconstructed image and acquire the conclusion that the small size of hologram aperture diffraction aggravates the speckle noise of reconstructed image and the speckle noise has been one of primary noise sources in the reconstruction process. In order to reduce the speckle noise resulting from little hologram aperture diffraction, we set an appropriate aperture function matching the recording parameter and aperture size of hologram and deconvolve the reconstructed image with it. The validity has been proved in theory and experiment. Therefore, it offers a brand-new thought and practical way to reduce the speckle noise in the reconstructed image of digital holography.

  8. Influence of the nonlinear phase and ASE noise on DPSK balanced optical receiver in optical fiber communication system

    Institute of Scientific and Technical Information of China (English)

    李蔚; 梅君瑶; 韩庆生; 王腾

    2009-01-01

    The analytical expression of bit error probability in a balanced differential phase-shift keying(DPSK) optical receiver considering nonlinear phase noise and EDFA ASE noise is given,which is very useful to estimate the performance of DPSK balanced and unbalanced receiver in optical communication system.Through analysis,if only nonlinear phase noise is considered,both the balance and unbalanced receivers have the same performances.But if adding the ASE noise of EDFA,the balanced receiver is better.

  9. Anthropogenic noise changes arthropod abundances.

    Science.gov (United States)

    Bunkley, Jessie P; McClure, Christopher J W; Kawahara, Akito Y; Francis, Clinton D; Barber, Jesse R

    2017-05-01

    Anthropogenic noise is a widespread and growing form of sensory pollution associated with the expansion of human infrastructure. One specific source of constant and intense noise is that produced by compressors used for the extraction and transportation of natural gas. Terrestrial arthropods play a central role in many ecosystems, and given that numerous species rely upon airborne sounds and substrate-borne vibrations in their life histories, we predicted that increased background sound levels or the presence of compressor noise would influence their distributions. In the second largest natural gas field in the United States (San Juan Basin, New Mexico, USA), we assessed differences in the abundances of terrestrial arthropod families and community structure as a function of compressor noise and background sound level. Using pitfall traps, we simultaneously sampled five sites adjacent to well pads that possessed operating compressors, and five alternate, quieter well pad sites that lacked compressors, but were otherwise similar. We found a negative association between sites with compressor noise or higher levels of background sound and the abundance of five arthropod families and one genus, a positive relationship between loud sites and the abundance of one family, and no relationship between noise level or compressor presence and abundance for six families and two genera. Despite these changes, we found no evidence of community turnover as a function of background sound level or site type (compressor and noncompressor). Our results indicate that anthropogenic noise differentially affects the abundances of some arthropod families. These preliminary findings point to a need to determine the direct and indirect mechanisms driving these observed responses. Given the diverse and important ecological functions provided by arthropods, changes in abundances could have ecological implications. Therefore, we recommend the consideration of arthropods in the environmental

  10. Common genetic variants influence human subcortical brain structures

    NARCIS (Netherlands)

    Hibar, Derrek P.; Stein, Jason L.; Renteria, Miguel E.; Arias-Vasquez, Alejandro; Desrivieres, Sylvane; Jahanshad, Neda; Toro, Roberto; Wittfeld, Katharina; Abramovic, Lucija; Andersson, Micael; Aribisala, Benjamin S.; Armstrong, Nicola J.; Bernard, Manon; Bohlken, Marc M.; Boks, Marco P.; Bralten, Janita; Brown, Andrew A.; Chakravarty, M. Mallar; Chen, Qiang; Ching, Christopher R. K.; Cuellar-Partida, Gabriel; den Braber, Anouk; Giddaluru, Sudheer; Goldman, Aaron L.; Grimm, Oliver; Guadalupe, Tulio; Hass, Johanna; Woldehawariat, Girma; Holmes, Avram J.; Hoogman, Martine; Janowitz, Deborah; Jia, Tianye; Kim, Sungeun; Klein, Marieke; Kraemer, Bernd; Lee, Phil H.; Loohuis, Loes M. Olde; Luciano, Michelle; Macare, Christine; Mather, Karen A.; Mattheisen, Manuel; Milaneschi, Yuri; Nho, Kwangsik; Papmeyer, Martina; Ramasamy, Adaikalavan; Risacher, Shannon L.; Roiz-Santianez, Roberto; Rose, Emma J.; Salami, Alireza; Saemann, Philipp G.; Schmaal, Lianne; Schork, Andrew J.; Shin, Jean; Strike, Lachlan T.; Teumer, Alexander; van Donkelaar, Marjolein M. J.; van Eijk, Kristel R.; Walters, Raymond K.; Westlye, Lars T.; Whelan, Christopher D.; Winkler, Anderson M.; Zwiers, Marcel P.; Alhusaini, Saud; Athanasiu, Lavinia; Ehrlich, Stefan; Hakobjan, Marina M. H.; Hartberg, Cecilie B.; Haukvik, Unn K.; Heister, Angelien J. G. A. M.; Hoehn, David; Kasperaviciute, Dalia; Liewald, David C. M.; Lopez, Lorna M.; Makkinje, Remco R. R.; Matarin, Mar; Naber, Marlies A. M.; McKay, D. Reese; Needham, Margaret; Nugent, Allison C.; Puetz, Benno; Royle, Natalie A.; Shen, Li; Sprooten, Emma; Trabzuni, Daniah; van der Marel, Saskia S. L.; van Hulzen, Kimm J. E.; Walton, Esther; Wolf, Christiane; Almasy, Laura; Ames, David; Arepalli, Sampath; Assareh, Amelia A.; Bastin, Mark E.; Brodaty, Henry; Bulayeva, Kazima B.; Carless, Melanie A.; Cichon, Sven; Corvin, Aiden; Curran, Joanne E.; Czisch, Michael; de Zubicaray, Greig I.; Dillman, Allissa; Duggirala, Ravi; Dyer, Thomas D.; Erk, Susanne; Fedko, Iryna O.; Ferrucci, Luigi; Foroud, Tatiana M.; Fox, Peter T.; Fukunaga, Masaki; Gibbs, J. Raphael; Goering, Harald H. H.; Green, Robert C.; Guelfi, Sebastian; Hansell, Narelle K.; Hartman, Catharina A.; Hegenscheid, Katrin; Heinz, Andreas; Hernandez, Dena G.; Heslenfeld, Dirk J.; Hoekstra, Pieter J.; Holsboer, Florian; Homuth, Georg; Hottenga, Jouke-Jan; Ikeda, Masashi; Jack, Clifford R.; Jenkinson, Mark; Johnson, Robert; Kanai, Ryota; Keil, Maria; Kent, Jack W.; Kochunov, Peter; Kwok, John B.; Lawrie, Stephen M.; Liu, Xinmin; Longo, Dan L.; McMahon, Katie L.; Meisenzah, Eva; Melle, Ingrid; Mahnke, Sebastian; Montgomery, Grant W.; Mostert, Jeanette C.; Muehleisen, Thomas W.; Nalls, Michael A.; Nichols, Thomas E.; Nilsson, Lars G.; Noethen, Markus M.; Ohi, Kazutaka; Olvera, Rene L.; Perez-Iglesias, Rocio; Pike, G. Bruce; Potkin, Steven G.; Reinvang, Ivar; Reppermund, Simone; Rietschel, Marcella; Romanczuk-Seiferth, Nina; Rosen, Glenn D.; Rujescu, Dan; Schnell, Knut; Schofield, Peter R.; Smith, Colin; Steen, Vidar M.; Sussmann, Jessika E.; Thalamuthu, Anbupalam; Toga, Arthur W.; Traynor, Bryan J.; Troncoso, Juan; Turner, Jessica A.; Valdes Hernandez, Maria C.; van't Ent, Dennis; van der Brug, Marcel; van der Wee, Nic J. A.; van Tol, Marie-Jose; Veltman, Dick J.; Wassink, Thomas H.; Westman, Eric; Zielke, Ronald H.; Zonderman, Alan B.; Ashbrook, David G.; Hager, Reinmar; Lu, Lu; McMahon, Francis J.; Morris, Derek W.; Williams, Robert W.; Brunner, Han G.; Buckner, Randy L.; Buitelaar, Jan K.; Cahn, Wiepke; Calhoun, Vince D.; Cavalleri, Gianpiero L.; Crespo-Facorro, Benedicto; Dale, Anders M.; Davies, Gareth E.; Delanty, Norman; Depondt, Chantal; Djurovic, Srdjan; Drevets, Wayne C.; Espeseth, Thomas; Gollub, Randy L.; Ho, Beng-Choon; Hoffman, Wolfgang; Hosten, Norbert; Kahn, Rene S.; Le Hellard, Stephanie; Meyer-Lindenberg, Andreas; Mueller-Myhsok, Bertram; Nauck, Matthias; Nyberg, Lars; Pandolfo, Massimo; Penninx, Brenda W. J. H.; Roffman, Joshua L.; Sisodiya, Sanjay M.; Smoller, Jordan W.; van Bokhoven, Hans; van Haren, Neeltje E. M.; Voelzke, Henry; Walter, Henrik; Weiner, Michael W.; Wen, Wei; White, Tonya; Agartz, Ingrid; Andreassen, Ole A.; Blangero, John; Boomsma, Dorret I.; Brouwer, Rachel M.; Cannon, Dara M.; Cookson, Mark R.; de Geus, Eco J. C.; Deary, Ian J.; Donohoe, Gary; Fernandez, Guillen; Fisher, Simon E.; Francks, Clyde; Glahn, David C.; Grabe, Hans J.; Gruber, Oliver; Hardy, John; Hashimoto, Ryota; Pol, Hilleke E. Hulshoff; Joensson, Erik G.; Kloszewska, Iwona; Lovestone, Simon; Mattay, Venkata S.; Mecocci, Patrizia; McDonald, Colm; McIntosh, Andrew M.; Ophoff, Roel A.; Paus, Tomas; Pausova, Zdenka; Ryten, Mina; Sachdev, Perminder S.; Saykin, Andrew J.; Simmons, Andy; Singleton, Andrew; Soininen, Hilkka; Wardlaw, Joanna M.; Weale, Michael E.; Weinberger, Daniel R.; Adams, Hieab H. H.; Launer, Lenore J.; Seiler, Stephan; Schmidt, Reinhold; Chauhan, Ganesh; Satizabal, Claudia L.; Becker, James T.; Yanek, Lisa; van der Lee, Sven J.; Ebling, Maritza; Fischl, Bruce; Longstreth, W. T.; Greve, Douglas; Schmidt, Helena; Nyquist, Paul; Vinke, Louis N.; van Duijn, Cornelia M.; Xue, Luting; Mazoyer, Bernard; Bis, Joshua C.; Gudnason, Vilmundur; Seshadri, Sudha; Ikram, M. Arfan; Martin, Nicholas G.; Wright, Margaret J.; Schumann, Gunter; Franke, Barbara; Thompson, Paul M.; Medland, Sarah E.

    2015-01-01

    The highly complex structure of the human brain is strongly shaped by genetic influences(1). Subcortical brain regions form circuits with cortical areas to coordinate movement(2), learning, memory(3) and motivation(4), and altered circuits can lead to abnormal behaviour and disease(5). To investigat

  11. Common genetic variants influence human subcortical brain structures

    NARCIS (Netherlands)

    D.P. Hibar (Derrek); J.L. Stein; M.E. Rentería (Miguel); A. Arias-Vásquez (Alejandro); S. Desrivières (Sylvane); N. Jahanshad (Neda); R. Toro (Roberto); K. Wittfeld (Katharina); L. Abramovic (Lucija); M. Andersson (Micael); B. Aribisala (Benjamin); N.J. Armstrong (Nicola J.); M. Bernard (Manon); M.M. Bohlken (Marc M.); M.P.M. Boks (Marco); L.B.C. Bralten (Linda); A.A. Brown (Andrew); M.M. Chakravarty (M. Mallar); Q. Chen (Qiang); C.R.K. Ching (Christopher); G. Cuellar-Partida (Gabriel); A. den Braber (Anouk); S. Giddaluru (Sudheer); A.L. Goldman (Aaron L.); O. Grimm (Oliver); T. Guadalupe (Tulio); J. Hass (Johanna); G. Woldehawariat (Girma); A.J. Holmes (Avram); M. Hoogman (Martine); D. Janowitz (Deborah); T. Jia (Tianye); S. Kim (Shinseog); M. Klein (Marieke); B. Kraemer (Bernd); P.H. Lee (Phil H.); L.M. Olde Loohuis (Loes M.); M. Luciano (Michelle); C. MacAre (Christine); R. Mather; M. Mattheisen (Manuel); Y. Milaneschi (Yuri); K. Nho (Kwangsik); M. Papmeyer (Martina); A. Ramasamy (Adaikalavan); S.L. Risacher (Shannon); R. Roiz-Santiañez (Roberto); E.J. Rose (Emma); A. Salami (Alireza); P.G. Sämann (Philipp); L. Schmaal (Lianne); N.J. Schork (Nicholas); J. Shin (Jean); V.M. Strike (Vanessa); A. Teumer (Alexander); M.M.J. Van Donkelaar (Marjolein M. J.); K.R. van Eijk (Kristel); R.K. Walters (Raymond); L.T. Westlye (Lars); C.D. Whelan (Christopher); A.M. Winkler (Anderson); M.P. Zwiers (Marcel); S. Alhusaini (Saud); L. Athanasiu (Lavinia); S.M. Ehrlich (Stefan); M. Hakobjan (Marina); C.B. Hartberg (Cecilie B.); U.K. Haukvik (Unn); A.J.G.A.M. Heister (Angelien J. G. A. M.); D. Hoehn (David); D. Kasperaviciute (Dalia); D.C. Liewald (David C.); L.M. Lopez (Lorna); R.R.R. Makkinje (Remco R. R.); M. Matarin (Mar); M.A.M. Naber (Marlies A. M.); D. Reese McKay; M. Needham (Margaret); A.C. Nugent (Allison); B. Pütz (Benno); N.A. Royle (Natalie); L. Shen (Li); R. Sprooten (Roy); D. Trabzuni (Danyah); S.S.L. Van Der Marel (Saskia S. L.); K.J.E. Van Hulzen (Kimm J. E.); E. Walton (Esther); A. Björnsson (Asgeir); L. Almasy (Laura); D. Ames (David); S. Arepalli (Sampath); A.A. Assareh; M.E. Bastin (Mark); H. Brodaty (Henry); K. Bulayeva (Kazima); M.A. Carless (Melanie); S. Cichon (Sven); A. Corvin (Aiden); J.E. Curran (Joanne); M. Czisch (Michael); G.I. de Zubicaray (Greig); A. Dillman (Allissa); A. Duggirala (Aparna); M.D. Dyer (Matthew); S. Erk; I. Fedko (Iryna); L. Ferrucci (Luigi); T. Foroud (Tatiana); P.T. Fox (Peter); M. Fukunaga (Masaki); J. Raphael Gibbs; H.H.H. Göring (Harald H.); R.C. Green (Robert C.); S. Guelfi (Sebastian); N.K. Hansell (Narelle); C.A. Hartman (Catharina); K. Hegenscheid (Katrin); J. Heinz (Judith); D.G. Hernandez (Dena); D.J. Heslenfeld (Dirk); P.J. Hoekstra (Pieter); F. Holsboer; G. Homuth (Georg); J.J. Hottenga (Jouke Jan); M. Ikeda (Masashi); C.R. Jack Jr. (Clifford); S. Jenkinson (Sarah); R. Johnson (Robert); R. Kanai (Ryota); M. Keil (Maria); J.W. Kent (Jack W.); P. Kochunov (Peter); J.B. Kwok (John B.); S. Lawrie (Stephen); X. Liu (Xinmin); D.L. Longo (Dan L.); K.L. Mcmahon (Katie); E. Meisenzahl (Eva); I. Melle (Ingrid); S. Mohnke (Sebastian); G.W. Montgomery (Grant); J.C. Mostert (Jeanette C.); T.W. Mühleisen (Thomas); M.A. Nalls (Michael); T.E. Nichols (Thomas); L.G. Nilsson; M.M. Nöthen (Markus); K. Ohi (Kazutaka); R.L. Olvera (Rene); R. Perez-Iglesias (Rocio); G. Bruce Pike; S.G. Potkin (Steven); I. Reinvang (Ivar); S. Reppermund; M. Rietschel (M.); N. Seiferth (Nina); G.D. Rosen (Glenn D.); D. Rujescu (Dan); K. Schnell (Kerry); C.J. Schofield (Christopher); C. Smith (Colin); V.M. Steen (Vidar); J. Sussmann (Jessika); A. Thalamuthu (Anbupalam); A.W. Toga (Arthur W.); B. Traynor (Bryan); J.C. Troncoso (Juan); J. Turner (Jessica); M.C. Valdés Hernández (Maria); D. van 't Ent (Dennis); M.P. van der Brug (Marcel); N.J. van der Wee (Nic); M.J.D. van Tol (Marie-José); D.J. Veltman (Dick); A.M.J. Wassink (Annemarie); E. Westman (Eric); R.H. Zielke (Ronald H.); A.B. Zonderman (Alan B.); D.G. Ashbrook (David G.); R. Hager (Reinmar); L. Lu (Lu); F.J. Mcmahon (Francis J); D.W. Morris (Derek W); R.W. Williams (Robert W.); H.G. Brunner; M. Buckner; J.K. Buitelaar (Jan K.); W. Cahn (Wiepke); V.D. Calhoun Vince D. (V.); G. Cavalleri (Gianpiero); B. Crespo-Facorro (Benedicto); A.M. Dale (Anders); G.E. Davies (Gareth); N. Delanty; C. Depondt (Chantal); S. Djurovic (Srdjan); D.A. Drevets (Douglas); T. Espeseth (Thomas); R.L. Gollub (Randy); B.C. Ho (Beng ); W. Hoffmann (Wolfgang)

    2015-01-01

    textabstractThe highly complex structure of the human brain is strongly shaped by genetic influences. Subcortical brain regions form circuits with cortical areas to coordinate movement, learning, memory and motivation, and altered circuits can lead to abnormal behaviour and disease. To investigate

  12. Common genetic variants influence human subcortical brain structures

    NARCIS (Netherlands)

    Hibar, D.P.; Stein, J.L.; Renteria, M.E.; Arias Vasquez, A.; Desrivieres, S.; Jahanshad, N.; Toro, R.; Wittfeld, K.; Abramovic, L.; Andersson, M.; Aribisala, B.S.; Armstrong, N.J.; Bernard, M.; Bohlken, M.M.; Boks, M.P.; Bralten, J.; Brown, A.A.; Chakravarty, M.M.; Chen, Q.; Ching, C.R.; Cuellar-Partida, G.; Braber, A.; Giddaluru, S.; Goldman, A.L.; Grimm, O.; Guadalupe, T.; Hass, J.; Woldehawariat, G.; Holmes, A.J.; Hoogman, M.; Janowitz, D.; Jia, T.; Kim, S.; Klein, M.; Kraemer, B.; Lee, P.H.; Olde Loohuis, L.M.; Luciano, M.; Macare, C.; Mather, K.A.; Mattheisen, M.; Milaneschi, Y.; Nho, K.; Papmeyer, M.; Ramasamy, A.; Risacher, S.L.; Roiz-Santianez, R.; Rose, E.J.; Salami, A.; Samann, P.G.; Schmaal, L.; Schork, A.J.; Shin, J.; Strike, L.T.; Teumer, A.; Donkelaar, M.M.J. van; Eijk, K.R. van; Walters, R.K.; Westlye, L.T.; Whelan, C.D.; Winkler, A.M.; Zwiers, M.P.; Alhusaini, S.; Athanasiu, L.; Ehrlich, S.; Hakobjan, M.M.; Hartberg, C.B.; Haukvik, U.K.; Heister, A.J.; Hoehn, D.; Kasperaviciute, D.; Liewald, D.C.; Lopez, L.M.; Makkinje, R.R.; Matarin, M.; Naber, M.; McKay, D.R.; Needham, M.; Nugent, A.C.; Putz, B.; Royle, N.A.; Shen, L.; Sprooten, E.; Trabzuni, D.; Marel, S.S. van der; Hulzen, K.J.E. van; Walton, E.; Wolf, C.; Almasy, L.; Ames, D.; Arepalli, S.; Assareh, A.A.; Bastin, M.E.; Brodaty, H.; Bulayeva, K.B.; Carless, M.A.; Cichon, S.; Corvin, A.; Curran, J.E.; Czisch, M.; Fisher, S.E.

    2015-01-01

    The highly complex structure of the human brain is strongly shaped by genetic influences. Subcortical brain regions form circuits with cortical areas to coordinate movement, learning, memory and motivation, and altered circuits can lead to abnormal behaviour and disease. To investigate how common

  13. Common genetic variants influence human subcortical brain structures

    NARCIS (Netherlands)

    Hibar, Derrek P.; Stein, Jason L.; Renteria, Miguel E.; Arias-Vasquez, Alejandro; Desrivieres, Sylvane; Jahanshad, Neda; Toro, Roberto; Wittfeld, Katharina; Abramovic, Lucija; Andersson, Micael; Aribisala, Benjamin S.; Armstrong, Nicola J.; Bernard, Manon; Bohlken, Marc M.; Boks, Marco P.; Bralten, Janita; Brown, Andrew A.; Chakravarty, M. Mallar; Chen, Qiang; Ching, Christopher R. K.; Cuellar-Partida, Gabriel; den Braber, Anouk; Giddaluru, Sudheer; Goldman, Aaron L.; Grimm, Oliver; Guadalupe, Tulio; Hass, Johanna; Woldehawariat, Girma; Holmes, Avram J.; Hoogman, Martine; Janowitz, Deborah; Jia, Tianye; Kim, Sungeun; Klein, Marieke; Kraemer, Bernd; Lee, Phil H.; Loohuis, Loes M. Olde; Luciano, Michelle; Macare, Christine; Mather, Karen A.; Mattheisen, Manuel; Milaneschi, Yuri; Nho, Kwangsik; Papmeyer, Martina; Ramasamy, Adaikalavan; Risacher, Shannon L.; Roiz-Santianez, Roberto; Rose, Emma J.; Salami, Alireza; Saemann, Philipp G.; Schmaal, Lianne; Schork, Andrew J.; Shin, Jean; Strike, Lachlan T.; Teumer, Alexander; van Donkelaar, Marjolein M. J.; van Eijk, Kristel R.; Walters, Raymond K.; Westlye, Lars T.; Whelan, Christopher D.; Winkler, Anderson M.; Zwiers, Marcel P.; Alhusaini, Saud; Athanasiu, Lavinia; Ehrlich, Stefan; Hakobjan, Marina M. H.; Hartberg, Cecilie B.; Haukvik, Unn K.; Heister, Angelien J. G. A. M.; Hoehn, David; Kasperaviciute, Dalia; Liewald, David C. M.; Lopez, Lorna M.; Makkinje, Remco R. R.; Matarin, Mar; Naber, Marlies A. M.; McKay, D. Reese; Needham, Margaret; Nugent, Allison C.; Puetz, Benno; Royle, Natalie A.; Shen, Li; Sprooten, Emma; Trabzuni, Daniah; van der Marel, Saskia S. L.; van Hulzen, Kimm J. E.; Walton, Esther; Wolf, Christiane; Almasy, Laura; Ames, David; Arepalli, Sampath; Assareh, Amelia A.; Bastin, Mark E.; Brodaty, Henry; Bulayeva, Kazima B.; Carless, Melanie A.; Cichon, Sven; Corvin, Aiden; Curran, Joanne E.; Czisch, Michael; de Zubicaray, Greig I.; Dillman, Allissa; Duggirala, Ravi; Dyer, Thomas D.; Erk, Susanne; Fedko, Iryna O.; Ferrucci, Luigi; Foroud, Tatiana M.; Fox, Peter T.; Fukunaga, Masaki; Gibbs, J. Raphael; Goering, Harald H. H.; Green, Robert C.; Guelfi, Sebastian; Hansell, Narelle K.; Hartman, Catharina A.; Hegenscheid, Katrin; Heinz, Andreas; Hernandez, Dena G.; Heslenfeld, Dirk J.; Hoekstra, Pieter J.; Holsboer, Florian; Homuth, Georg; Hottenga, Jouke-Jan; Ikeda, Masashi; Jack, Clifford R.; Jenkinson, Mark; Johnson, Robert; Kanai, Ryota; Keil, Maria; Kent, Jack W.; Kochunov, Peter; Kwok, John B.; Lawrie, Stephen M.; Liu, Xinmin; Longo, Dan L.; McMahon, Katie L.; Meisenzah, Eva; Melle, Ingrid; Mahnke, Sebastian; Montgomery, Grant W.; Mostert, Jeanette C.; Muehleisen, Thomas W.; Nalls, Michael A.; Nichols, Thomas E.; Nilsson, Lars G.; Noethen, Markus M.; Ohi, Kazutaka; Olvera, Rene L.; Perez-Iglesias, Rocio; Pike, G. Bruce; Potkin, Steven G.; Reinvang, Ivar; Reppermund, Simone; Rietschel, Marcella; Romanczuk-Seiferth, Nina; Rosen, Glenn D.; Rujescu, Dan; Schnell, Knut; Schofield, Peter R.; Smith, Colin; Steen, Vidar M.; Sussmann, Jessika E.; Thalamuthu, Anbupalam; Toga, Arthur W.; Traynor, Bryan J.; Troncoso, Juan; Turner, Jessica A.; Valdes Hernandez, Maria C.; van't Ent, Dennis; van der Brug, Marcel; van der Wee, Nic J. A.; van Tol, Marie-Jose; Veltman, Dick J.; Wassink, Thomas H.; Westman, Eric; Zielke, Ronald H.; Zonderman, Alan B.; Ashbrook, David G.; Hager, Reinmar; Lu, Lu; McMahon, Francis J.; Morris, Derek W.; Williams, Robert W.; Brunner, Han G.; Buckner, Randy L.; Buitelaar, Jan K.; Cahn, Wiepke; Calhoun, Vince D.; Cavalleri, Gianpiero L.; Crespo-Facorro, Benedicto; Dale, Anders M.; Davies, Gareth E.; Delanty, Norman; Depondt, Chantal; Djurovic, Srdjan; Drevets, Wayne C.; Espeseth, Thomas; Gollub, Randy L.; Ho, Beng-Choon; Hoffman, Wolfgang; Hosten, Norbert; Kahn, Rene S.; Le Hellard, Stephanie; Meyer-Lindenberg, Andreas; Mueller-Myhsok, Bertram; Nauck, Matthias; Nyberg, Lars; Pandolfo, Massimo; Penninx, Brenda W. J. H.; Roffman, Joshua L.; Sisodiya, Sanjay M.; Smoller, Jordan W.; van Bokhoven, Hans; van Haren, Neeltje E. M.; Voelzke, Henry; Walter, Henrik; Weiner, Michael W.; Wen, Wei; White, Tonya; Agartz, Ingrid; Andreassen, Ole A.; Blangero, John; Boomsma, Dorret I.; Brouwer, Rachel M.; Cannon, Dara M.; Cookson, Mark R.; de Geus, Eco J. C.; Deary, Ian J.; Donohoe, Gary; Fernandez, Guillen; Fisher, Simon E.; Francks, Clyde; Glahn, David C.; Grabe, Hans J.; Gruber, Oliver; Hardy, John; Hashimoto, Ryota; Pol, Hilleke E. Hulshoff; Joensson, Erik G.; Kloszewska, Iwona; Lovestone, Simon; Mattay, Venkata S.; Mecocci, Patrizia; McDonald, Colm; McIntosh, Andrew M.; Ophoff, Roel A.; Paus, Tomas; Pausova, Zdenka; Ryten, Mina; Sachdev, Perminder S.; Saykin, Andrew J.; Simmons, Andy; Singleton, Andrew; Soininen, Hilkka; Wardlaw, Joanna M.; Weale, Michael E.; Weinberger, Daniel R.; Adams, Hieab H. H.; Launer, Lenore J.; Seiler, Stephan; Schmidt, Reinhold; Chauhan, Ganesh; Satizabal, Claudia L.; Becker, James T.; Yanek, Lisa; van der Lee, Sven J.; Ebling, Maritza; Fischl, Bruce; Longstreth, W. T.; Greve, Douglas; Schmidt, Helena; Nyquist, Paul; Vinke, Louis N.; van Duijn, Cornelia M.; Xue, Luting; Mazoyer, Bernard; Bis, Joshua C.; Gudnason, Vilmundur; Seshadri, Sudha; Ikram, M. Arfan; Martin, Nicholas G.; Wright, Margaret J.; Schumann, Gunter; Franke, Barbara; Thompson, Paul M.; Medland, Sarah E.

    2015-01-01

    The highly complex structure of the human brain is strongly shaped by genetic influences(1). Subcortical brain regions form circuits with cortical areas to coordinate movement(2), learning, memory(3) and motivation(4), and altered circuits can lead to abnormal behaviour and disease(5). To

  14. Common genetic variants influence human subcortical brain structures

    NARCIS (Netherlands)

    D.P. Hibar (Derrek); J.L. Stein; M.E. Rentería (Miguel); A. Arias-Vásquez (Alejandro); S. Desrivières (Sylvane); N. Jahanshad (Neda); R. Toro (Roberto); K. Wittfeld (Katharina); L. Abramovic; M. Andersson (Micael); B. Aribisala (Benjamin); N.J. Armstrong (Nicola J.); M. Bernard (Manon); M.M. Bohlken (Marc M.); M.P.M. Boks (Marco); L.B.C. Bralten (Linda); A.A. Brown (Andrew); M.M. Chakravarty (M. Mallar); Q. Chen (Qiang); C.R.K. Ching (Christopher); G. Cuellar-Partida (Gabriel); A. den Braber (Anouk); S. Giddaluru (Sudheer); A.L. Goldman (Aaron L.); O. Grimm (Oliver); T. Guadalupe (Tulio); J. Hass (Johanna); G. Woldehawariat (Girma); A.J. Holmes (Avram); M. Hoogman (Martine); D. Janowitz (Deborah); T. Jia (Tianye); S. Kim (Shinseog); M. Klein (Marieke); B. Kraemer (Bernd); P.H. Lee (Phil H.); L.M. Olde Loohuis (Loes M.); M. Luciano (Michelle); C. MacAre (Christine); R. Mather; M. Mattheisen (Manuel); Y. Milaneschi (Yuri); K. Nho (Kwangsik); M. Papmeyer (Martina); A. Ramasamy (Adaikalavan); S.L. Risacher (Shannon); R. Roiz-Santiañez (Roberto); E.J. Rose (Emma); A. Salami (Alireza); P.G. Sämann (Philipp); L. Schmaal (Lianne); N.J. Schork (Nicholas); J. Shin (Jean); V.M. Strike (Vanessa); A. Teumer (Alexander); M.M.J. Van Donkelaar (Marjolein M. J.); K.R. van Eijk (Kristel); R.K. Walters (Raymond); L.T. Westlye (Lars); C.D. Whelan (Christopher); A.M. Winkler (Anderson); M.P. Zwiers (Marcel); S. Alhusaini (Saud); L. Athanasiu (Lavinia); S.M. Ehrlich (Stefan); M. Hakobjan (Marina); C.B. Hartberg (Cecilie B.); U.K. Haukvik (Unn); A.J.G.A.M. Heister (Angelien J. G. A. M.); D. Hoehn (David); D. Kasperaviciute (Dalia); D.C. Liewald (David C.); L.M. Lopez (Lorna); R.R.R. Makkinje (Remco R. R.); M. Matarin (Mar); M.A.M. Naber (Marlies A. M.); D. Reese McKay; M. Needham (Margaret); A.C. Nugent (Allison); B. Pütz (Benno); N.A. Royle (Natalie); L. Shen (Li); R. Sprooten (Roy); D. Trabzuni (Danyah); S.S.L. Van Der Marel (Saskia S. L.); K.J.E. Van Hulzen (Kimm J. E.); E. Walton (Esther); A. Björnsson (Asgeir); L. Almasy (Laura); D. Ames (David); S. Arepalli (Sampath); A.A. Assareh; M.E. Bastin (Mark); H. Brodaty (Henry); K. Bulayeva (Kazima); M.A. Carless (Melanie); S. Cichon (Sven); A. Corvin (Aiden); J.E. Curran (Joanne); M. Czisch (Michael); G.I. de Zubicaray (Greig); A. Dillman (Allissa); A. Duggirala (Aparna); M.D. Dyer (Matthew); S. Erk; I. Fedko (Iryna); L. Ferrucci (Luigi); T. Foroud (Tatiana); P.T. Fox (Peter); M. Fukunaga (Masaki); J. Raphael Gibbs; H.H.H. Göring (Harald H.); R.C. Green (Robert C.); S. Guelfi (Sebastian); N.K. Hansell (Narelle); C.A. Hartman (Catharina); K. Hegenscheid (Katrin); J. Heinz (Judith); D.G. Hernandez (Dena); D.J. Heslenfeld (Dirk); P.J. Hoekstra (Pieter); F. Holsboer; G. Homuth (Georg); J.J. Hottenga (Jouke Jan); M. Ikeda (Masashi); C.R. Jack Jr. (Clifford); S. Jenkinson (Sarah); R. Johnson (Robert); R. Kanai (Ryota); M. Keil (Maria); J.W. Kent (Jack W.); P. Kochunov (Peter); J.B. Kwok (John B.); S. Lawrie (Stephen); X. Liu (Xinmin); D.L. Longo (Dan L.); K.L. Mcmahon (Katie); E. Meisenzahl (Eva); I. Melle (Ingrid); S. Mohnke (Sebastian); G.W. Montgomery (Grant); J.C. Mostert (Jeanette C.); T.W. Mühleisen (Thomas); M.A. Nalls (Michael); T.E. Nichols (Thomas); L.G. Nilsson; M.M. Nöthen (Markus); K. Ohi (Kazutaka); R.L. Olvera (Rene); R. Perez-Iglesias (Rocio); G. Bruce Pike; S.G. Potkin (Steven); I. Reinvang (Ivar); S. Reppermund; M. Rietschel (M.); N. Seiferth (Nina); G.D. Rosen (Glenn D.); D. Rujescu (Dan); K. Schnell (Kerry); C.J. Schofield (Christopher); C. Smith (Colin); V.M. Steen (Vidar); J. Sussmann (Jessika); A. Thalamuthu (Anbupalam); A.W. Toga (Arthur W.); B. Traynor (Bryan); J.C. Troncoso (Juan); J. Turner (Jessica); M.C. Valdés Hernández (Maria); D. van 't Ent (Dennis); M.P. van der Brug (Marcel); N.J. van der Wee (Nic); M.J.D. van Tol (Marie-José); D.J. Veltman (Dick); A.M.J. Wassink (Annemarie); E. Westman (Eric); R.H. Zielke (Ronald H.); A.B. Zonderman (Alan B.); D.G. Ashbrook (David G.); R. Hager (Reinmar); L. Lu (Lu); F.J. Mcmahon (Francis J); D.W. Morris (Derek W); R.W. Williams (Robert W.); H.G. Brunner; M. Buckner; J.K. Buitelaar (Jan K.); W. Cahn (Wiepke); V.D. Calhoun Vince D. (V.); G. Cavalleri (Gianpiero); B. Crespo-Facorro (Benedicto); A.M. Dale (Anders); G.E. Davies (Gareth); N. Delanty; C. Depondt (Chantal); S. Djurovic (Srdjan); D.A. Drevets (Douglas); T. Espeseth (Thomas); R.L. Gollub (Randy); B.C. Ho (Beng ); W. Hoffmann (Wolfgang); N. Hosten (Norbert); R. Kahn; S. Le Hellard (Stephanie); A. Meyer-Lindenberg; B. Müller-Myhsok (B.); M. Nauck (Matthias); L. Nyberg (Lars); M. Pandolfo (Massimo); B.W.J.H. Penninx (Brenda); J.L. Roffman (Joshua); S.M. Sisodiya (Sanjay); J.W. Smoller; H. van Bokhoven (Hans); N.E.M. van Haren (Neeltje E.); H. Völzke (Henry); H.J. Walter (Henrik); M.W. Weiner (Michael); W. Wen (Wei); T.J.H. White (Tonya); I. Agartz (Ingrid); O.A. Andreassen (Ole A.); J. Blangero (John); D.I. Boomsma (Dorret); R.M. Brouwer (Rachel); D.M. Cannon (Dara); M.R. Cookson (Mark); E.J.C. de Geus (Eco); I.J. Deary (Ian J.); D.J. Donohoe (Dennis); G. Fernandez (Guillén); S.E. Fisher (Simon); C. Francks (Clyde); D.C. Glahn (David); H.J. Grabe (Hans Jörgen); O. Gruber (Oliver); J. Hardy (John); R. Hashimoto (Ryota); H.E. Hulshoff Pol (Hilleke); E.G. Jönsson (Erik); I. Kloszewska (Iwona); S. Lovestone (Simon); V.S. Mattay (Venkata S.); P. Mecocci (Patrizia); C. McDonald (Colm); A.M. McIntosh (Andrew); R.A. Ophoff (Roel); T. Paus (Tomas); Z. Pausova (Zdenka); M. Ryten (Mina); P.S. Sachdev (Perminder); A.J. Saykin (Andrew); A. Simmons (Andrew); A. Singleton (Andrew); H. Soininen (H.); J.M. Wardlaw (J.); M.E. Weale (Michael); D.R. Weinberger (Daniel); H.H.H. Adams (Hieab); L.J. Launer (Lenore); S. Seiler (Stephan); R. Schmidt (Reinhold); G. Chauhan (Ganesh); C.L. Satizabal (Claudia L.); J.T. Becker (James); L.R. Yanek (Lisa); S. van der Lee (Sven); M. Ebling (Maritza); B. Fischl (Bruce); W.T. Longstreth Jr; D. Greve (Douglas); R. Schmidt (Reinhold); P. Nyquist (Paul); L.N. Vinke (Louis N.); C.M. van Duijn (Cock); L. Xue (Luting); B. Mazoyer (Bernard); J.C. Bis (Joshua); V. Gudnason (Vilmundur); S. Seshadri (Sudha); M.A. Ikram (Arfan); N.G. Martin (Nicholas); M.J. Wright (Margaret); G. Schumann (Gunter); B. Franke (Barbara); P.M. Thompson (Paul); S.E. Medland (Sarah Elizabeth)

    2015-01-01

    textabstractThe highly complex structure of the human brain is strongly shaped by genetic influences. Subcortical brain regions form circuits with cortical areas to coordinate movement, learning, memory and motivation, and altered circuits can lead to abnormal behaviour and disease. To investigate h

  15. Vision Influence on Whole-Body Human Vibration Comfort Levels

    Directory of Open Access Journals (Sweden)

    Maria Lúcia Machado Duarte

    2006-01-01

    Full Text Available The well being of people needs to be a priority in the modern world. In that respect, vibration cannot be one more cause of stress. Besides that, vibration comfort is very important, since high levels may cause health or even tasks' accomplishment problems. Several parameters may influence the levels of vibration a human being supports. Among them, one can mention the influence of gender, age, corporeal mass index (CMI, temperature, humor, anxiety, hearing, posture, vision, etc. The first three parameters mentioned were already investigated in previous studies undertaken by GRAVI (Group of Acoustics and Vibration researchers. In this paper, the influence of vision is evaluated. The main objective with this series of tests performed is to try to quantify in a future the influence of each parameter in a global vibration comfort level. Conclusions are presented for the parameter investigated.

  16. Influences of quantum noises on direct-modulated properties of 1.3-μm InGaAsP/InP laser diodes

    Institute of Scientific and Technical Information of China (English)

    Wang Jun; Ma Xiao-Yu; Bai Yi-Ming; Cao Li; Wu Da-Jin

    2006-01-01

    Due to the zero dispersion point at 1.3μm in optical fibres, 1.3-μm InGaAsP/InP laser diodes have become main light sources in fibre communication systems recently. Influences of quantum noises on direct-modulated properties of single-mode 1.3-μm InGaAsP/InP laser diodes are investigated in this article. Considering the carrier and photon noises and the cross-correlation between the two noises, the power spectrum of the photon density and the signal-to-noise ratio (SNR) of the direct-modulated single-mode laser system are calculated using the linear approximation method. We find that the stochastic resonance (SR) always appears in the dependence of the SNR on the bias current density, and is strongly affected by the cross-correlation coefficient between the carrier and photon noises, the frequency of modulation signal, and the photon lifetime in the laser cavity. Hence, it is promising to use the SR mechanism to enhance the SNRof direct-modulated InGaAsP/InP laser diodes and improve the quality of optical fibre communication systems.

  17. Underwater noise levels in UK waters

    Science.gov (United States)

    Merchant, Nathan D.; Brookes, Kate L.; Faulkner, Rebecca C.; Bicknell, Anthony W. J.; Godley, Brendan J.; Witt, Matthew J.

    2016-11-01

    Underwater noise from human activities appears to be rising, with ramifications for acoustically sensitive marine organisms and the functioning of marine ecosystems. Policymakers are beginning to address the risk of ecological impact, but are constrained by a lack of data on current and historic noise levels. Here, we present the first nationally coordinated effort to quantify underwater noise levels, in support of UK policy objectives under the EU Marine Strategy Framework Directive (MSFD). Field measurements were made during 2013-2014 at twelve sites around the UK. Median noise levels ranged from 81.5-95.5 dB re 1 μPa for one-third octave bands from 63-500 Hz. Noise exposure varied considerably, with little anthropogenic influence at the Celtic Sea site, to several North Sea sites with persistent vessel noise. Comparison of acoustic metrics found that the RMS level (conventionally used to represent the mean) was highly skewed by outliers, exceeding the 97th percentile at some frequencies. We conclude that environmental indicators of anthropogenic noise should instead use percentiles, to ensure statistical robustness. Power analysis indicated that at least three decades of continuous monitoring would be required to detect trends of similar magnitude to historic rises in noise levels observed in the Northeast Pacific.

  18. Common genetic variants influence human subcortical brain structures.

    Science.gov (United States)

    Hibar, Derrek P; Stein, Jason L; Renteria, Miguel E; Arias-Vasquez, Alejandro; Desrivières, Sylvane; Jahanshad, Neda; Toro, Roberto; Wittfeld, Katharina; Abramovic, Lucija; Andersson, Micael; Aribisala, Benjamin S; Armstrong, Nicola J; Bernard, Manon; Bohlken, Marc M; Boks, Marco P; Bralten, Janita; Brown, Andrew A; Chakravarty, M Mallar; Chen, Qiang; Ching, Christopher R K; Cuellar-Partida, Gabriel; den Braber, Anouk; Giddaluru, Sudheer; Goldman, Aaron L; Grimm, Oliver; Guadalupe, Tulio; Hass, Johanna; Woldehawariat, Girma; Holmes, Avram J; Hoogman, Martine; Janowitz, Deborah; Jia, Tianye; Kim, Sungeun; Klein, Marieke; Kraemer, Bernd; Lee, Phil H; Olde Loohuis, Loes M; Luciano, Michelle; Macare, Christine; Mather, Karen A; Mattheisen, Manuel; Milaneschi, Yuri; Nho, Kwangsik; Papmeyer, Martina; Ramasamy, Adaikalavan; Risacher, Shannon L; Roiz-Santiañez, Roberto; Rose, Emma J; Salami, Alireza; Sämann, Philipp G; Schmaal, Lianne; Schork, Andrew J; Shin, Jean; Strike, Lachlan T; Teumer, Alexander; van Donkelaar, Marjolein M J; van Eijk, Kristel R; Walters, Raymond K; Westlye, Lars T; Whelan, Christopher D; Winkler, Anderson M; Zwiers, Marcel P; Alhusaini, Saud; Athanasiu, Lavinia; Ehrlich, Stefan; Hakobjan, Marina M H; Hartberg, Cecilie B; Haukvik, Unn K; Heister, Angelien J G A M; Hoehn, David; Kasperaviciute, Dalia; Liewald, David C M; Lopez, Lorna M; Makkinje, Remco R R; Matarin, Mar; Naber, Marlies A M; McKay, D Reese; Needham, Margaret; Nugent, Allison C; Pütz, Benno; Royle, Natalie A; Shen, Li; Sprooten, Emma; Trabzuni, Daniah; van der Marel, Saskia S L; van Hulzen, Kimm J E; Walton, Esther; Wolf, Christiane; Almasy, Laura; Ames, David; Arepalli, Sampath; Assareh, Amelia A; Bastin, Mark E; Brodaty, Henry; Bulayeva, Kazima B; Carless, Melanie A; Cichon, Sven; Corvin, Aiden; Curran, Joanne E; Czisch, Michael; de Zubicaray, Greig I; Dillman, Allissa; Duggirala, Ravi; Dyer, Thomas D; Erk, Susanne; Fedko, Iryna O; Ferrucci, Luigi; Foroud, Tatiana M; Fox, Peter T; Fukunaga, Masaki; Gibbs, J Raphael; Göring, Harald H H; Green, Robert C; Guelfi, Sebastian; Hansell, Narelle K; Hartman, Catharina A; Hegenscheid, Katrin; Heinz, Andreas; Hernandez, Dena G; Heslenfeld, Dirk J; Hoekstra, Pieter J; Holsboer, Florian; Homuth, Georg; Hottenga, Jouke-Jan; Ikeda, Masashi; Jack, Clifford R; Jenkinson, Mark; Johnson, Robert; Kanai, Ryota; Keil, Maria; Kent, Jack W; Kochunov, Peter; Kwok, John B; Lawrie, Stephen M; Liu, Xinmin; Longo, Dan L; McMahon, Katie L; Meisenzahl, Eva; Melle, Ingrid; Mohnke, Sebastian; Montgomery, Grant W; Mostert, Jeanette C; Mühleisen, Thomas W; Nalls, Michael A; Nichols, Thomas E; Nilsson, Lars G; Nöthen, Markus M; Ohi, Kazutaka; Olvera, Rene L; Perez-Iglesias, Rocio; Pike, G Bruce; Potkin, Steven G; Reinvang, Ivar; Reppermund, Simone; Rietschel, Marcella; Romanczuk-Seiferth, Nina; Rosen, Glenn D; Rujescu, Dan; Schnell, Knut; Schofield, Peter R; Smith, Colin; Steen, Vidar M; Sussmann, Jessika E; Thalamuthu, Anbupalam; Toga, Arthur W; Traynor, Bryan J; Troncoso, Juan; Turner, Jessica A; Valdés Hernández, Maria C; van 't Ent, Dennis; van der Brug, Marcel; van der Wee, Nic J A; van Tol, Marie-Jose; Veltman, Dick J; Wassink, Thomas H; Westman, Eric; Zielke, Ronald H; Zonderman, Alan B; Ashbrook, David G; Hager, Reinmar; Lu, Lu; McMahon, Francis J; Morris, Derek W; Williams, Robert W; Brunner, Han G; Buckner, Randy L; Buitelaar, Jan K; Cahn, Wiepke; Calhoun, Vince D; Cavalleri, Gianpiero L; Crespo-Facorro, Benedicto; Dale, Anders M; Davies, Gareth E; Delanty, Norman; Depondt, Chantal; Djurovic, Srdjan; Drevets, Wayne C; Espeseth, Thomas; Gollub, Randy L; Ho, Beng-Choon; Hoffmann, Wolfgang; Hosten, Norbert; Kahn, René S; Le Hellard, Stephanie; Meyer-Lindenberg, Andreas; Müller-Myhsok, Bertram; Nauck, Matthias; Nyberg, Lars; Pandolfo, Massimo; Penninx, Brenda W J H; Roffman, Joshua L; Sisodiya, Sanjay M; Smoller, Jordan W; van Bokhoven, Hans; van Haren, Neeltje E M; Völzke, Henry; Walter, Henrik; Weiner, Michael W; Wen, Wei; White, Tonya; Agartz, Ingrid; Andreassen, Ole A; Blangero, John; Boomsma, Dorret I; Brouwer, Rachel M; Cannon, Dara M; Cookson, Mark R; de Geus, Eco J C; Deary, Ian J; Donohoe, Gary; Fernández, Guillén; Fisher, Simon E; Francks, Clyde; Glahn, David C; Grabe, Hans J; Gruber, Oliver; Hardy, John; Hashimoto, Ryota; Hulshoff Pol, Hilleke E; Jönsson, Erik G; Kloszewska, Iwona; Lovestone, Simon; Mattay, Venkata S; Mecocci, Patrizia; McDonald, Colm; McIntosh, Andrew M; Ophoff, Roel A; Paus, Tomas; Pausova, Zdenka; Ryten, Mina; Sachdev, Perminder S; Saykin, Andrew J; Simmons, Andy

    2015-04-01

    The highly complex structure of the human brain is strongly shaped by genetic influences. Subcortical brain regions form circuits with cortical areas to coordinate movement, learning, memory and motivation, and altered circuits can lead to abnormal behaviour and disease. To investigate how common genetic variants affect the structure of these brain regions, here we conduct genome-wide association studies of the volumes of seven subcortical regions and the intracranial volume derived from magnetic resonance images of 30,717 individuals from 50 cohorts. We identify five novel genetic variants influencing the volumes of the putamen and caudate nucleus. We also find stronger evidence for three loci with previously established influences on hippocampal volume and intracranial volume. These variants show specific volumetric effects on brain structures rather than global effects across structures. The strongest effects were found for the putamen, where a novel intergenic locus with replicable influence on volume (rs945270; P = 1.08 × 10(-33); 0.52% variance explained) showed evidence of altering the expression of the KTN1 gene in both brain and blood tissue. Variants influencing putamen volume clustered near developmental genes that regulate apoptosis, axon guidance and vesicle transport. Identification of these genetic variants provides insight into the causes of variability in human brain development, and may help to determine mechanisms of neuropsychiatric dysfunction.

  19. Attitudes toward noise, perceived hearing symptoms, and reported use of hearing protection among college students: Influence of youth culture.

    Science.gov (United States)

    Balanay, Jo Anne G; Kearney, Gregory D

    2015-01-01

    The purpose of this study was to assess the attitude toward noise, perceived hearing symptoms, noisy activities that were participated in, and factors associated with hearing protection use among college students. A 44-item online survey was completed by 2,151 college students (aged 17 years and above) to assess the attitudes toward noise, perceived hearing symptoms related to noise exposure, and use of hearing protection around noisy activities. Among the participants, 39.6% experienced at least one hearing symptom, with ear pain as the most frequently reported (22.5%). About 80% of the participants were involved in at least one noise activity, out of which 41% reported the use of hearing protection. A large majority of those with ear pain, hearing loss, permanent tinnitus, and noise sensitivity was involved in attending a sporting event, which was the most reported noisy activity. The highest reported hearing protection use was in the use of firearms, and the lowest in discos/ dances. The reported use of hearing protection is associated with having at least one hearing symptom but the relationship is stronger with tinnitus, hearing loss, and ear pain (χ² = 30.5-43.5, Pstudent health services, involving student groups in noise-induced hearing loss (NIHL) awareness and prevention, and establishing noise level limitations for all on-campus events.

  20. Factors influencing trace element composition in human teeth

    Energy Technology Data Exchange (ETDEWEB)

    Tandon, L. [Los Alamos National Lab., NM (United States); Iyengar, G.V. [Biomineral Sciences International, Inc., Bethesda, MD (United States)

    1997-12-01

    The authors recently compiled and reviewed the literature published in or after 1978 for 45 major, minor, and trace elements in human teeth as a part of an International Atomic Energy Agency (IAEA) study. The purpose of this paper is to discuss the various factors that influence the concentration levels of certain trace elements in human teeth. The sampling practices and analytical techniques that are applicable for trace element analysis are also discussed. It is also our intention to identify reference range of values, where data permit such conclusions. The scrutiny was designed to identify only the healthy permanent teeth, and values from teeth with fillings, caries, or periodontal diseases were eliminated.

  1. Biases in human sequential predictions as a consequence of incorrect world models, noise and limited memory

    NARCIS (Netherlands)

    Narain, D.; Beers, R.J. van; Smeets, J.B.J.

    2016-01-01

    Recent studies demonstrate that biases found in human behavior can be explained by rational agents that make incorrect generative-model assumptions. While predicting a sequence of uncorrelated events, humans are biased towards overestimating its serial correlation. We demonstrate how such biases may

  2. Environmental influences on human growth and development: historical review and case study of contemporary influences.

    Science.gov (United States)

    Schell, Lawrence M; Gallo, Mia V; Ravenscroft, Julia

    2009-01-01

    Over the past 100 years, the study of environmental influences on human physical growth and development has focused on the influences of social and economic factors; family and household characteristics; urbanization/modernization; nutrition; and features of the physical environment such as altitude, temperature and climate. Continuing in this tradition are current investigations into the roles of pollutants and other aspects of the human-made environment in affecting patterns of human growth and development, specifically the timing of sexual maturation and the development of obesity. Some of the methodological problems in conducting such studies are presented, as are results from an ongoing investigation among one Native American community that show relationships of pollutants to sexual maturation, overweight/obesity and thyroid system function which can impact growth and maturation.

  3. On the use of sensor fusion to reduce the impact of rotational and additive noise in human activity recognition.

    Science.gov (United States)

    Banos, Oresti; Damas, Miguel; Pomares, Hector; Rojas, Ignacio

    2012-01-01

    The main objective of fusion mechanisms is to increase the individual reliability of the systems through the use of the collectivity knowledge. Moreover, fusion models are also intended to guarantee a certain level of robustness. This is particularly required for problems such as human activity recognition where runtime changes in the sensor setup seriously disturb the reliability of the initial deployed systems. For commonly used recognition systems based on inertial sensors, these changes are primarily characterized as sensor rotations, displacements or faults related to the batteries or calibration. In this work we show the robustness capabilities of a sensor-weighted fusion model when dealing with such disturbances under different circumstances. Using the proposed method, up to 60% outperformance is obtained when a minority of the sensors are artificially rotated or degraded, independent of the level of disturbance (noise) imposed. These robustness capabilities also apply for any number of sensors affected by a low to moderate noise level. The presented fusion mechanism compensates the poor performance that otherwise would be obtained when just a single sensor is considered.

  4. On the Use of Sensor Fusion to Reduce the Impact of Rotational and Additive Noise in Human Activity Recognition

    Directory of Open Access Journals (Sweden)

    Ignacio Rojas

    2012-06-01

    Full Text Available The main objective of fusion mechanisms is to increase the individual reliability of the systems through the use of the collectivity knowledge. Moreover, fusion models are also intended to guarantee a certain level of robustness. This is particularly required for problems such as human activity recognition where runtime changes in the sensor setup seriously disturb the reliability of the initial deployed systems. For commonly used recognition systems based on inertial sensors, these changes are primarily characterized as sensor rotations, displacements or faults related to the batteries or calibration. In this work we show the robustness capabilities of a sensor-weighted fusion model when dealing with such disturbances under different circumstances. Using the proposed method, up to 60% outperformance is obtained when a minority of the sensors are artificially rotated or degraded, independent of the level of disturbance (noise imposed. These robustness capabilities also apply for any number of sensors affected by a low to moderate noise level. The presented fusion mechanism compensates the poor performance that otherwise would be obtained when just a single sensor is considered.

  5. Humans, Fish, and Whales: How Right Whales Modify Calling Behavior in Response to Shifting Background Noise Conditions.

    Science.gov (United States)

    Parks, Susan E; Groch, Karina; Flores, Paulo; Sousa-Lima, Renata; Urazghildiiev, Ildar R

    2016-01-01

    This study investigates the role of behavioral plasticity in the variation of sound production of southern right whales (Eubalaena australis) in response to changes in the ambient background noise conditions. Data were collected from southern right whales in Brazilian waters in October and November 2011. The goal of this study was to quantify differences in right whale vocalizations recorded in low background noise as a control, fish chorus noise, and vessel noise. Variation in call parameters were detected among the three background noise conditions and have implications for future studies of noise effects on whale sound production.

  6. Influence of Coloured Correlated Noises on Probability Distribution and Mean of Tumour Cell Number in the Logistic Growth Model

    Institute of Scientific and Technical Information of China (English)

    HAN Li-Bo; GONG Xiao-Long; CAO Li; WU Da-Jin

    2007-01-01

    An approximate Fokker-P1anck equation for the logistic growth model which is driven by coloured correlated noises is derived by applying the Novikov theorem and the Fox approximation. The steady-state probability distribution (SPD) and the mean of the tumour cell number are analysed. It is found that the SPD is the single extremum configuration when the degree of correlation between the multiplicative and additive noises, λ, is in -1<λ ≤ 0 and can be the double extrema in 0<λ<1. A configuration transition occurs because of the variation of noise parameters. A minimum appears in the curve of the mean of the steady-state tumour cell number, 〈x〉, versus λ. The position and the value of the minimum are controlled by the noise-correlated times.

  7. Common genetic variants influence human subcortical brain structures

    OpenAIRE

    Hibar, Derrek P.; Stein, Jason L.; Renteria, Miguel E.; Arias-Vasquez, Alejandro,; Desrivieres, Sylvane; Jahanshad, Neda; Toro, Roberto; Wittfeld, Katharina; Abramovic, Lucija; Andersson, Micael; Aribisala, Benjamin S.; Armstrong, Nicola J.; Bernard, Manon; Bohlken, Marc M.; Boks, Marco P

    2015-01-01

    The highly complex structure of the human brain is strongly shaped by genetic influences(1). Subcortical brain regions form circuits with cortical areas to coordinate movement(2), learning, memory(3) and motivation(4), and altered circuits can lead to abnormal behaviour and disease(5). To investigate how common genetic variants affect the structure of these brain regions, here we conduct genome-wide association studies of the volumes of seven subcortical regions and the intracranial volume de...

  8. A study on the effects of human age, type of computer and noise on operators' performance of a data entry task.

    Science.gov (United States)

    Khan, Zahid A; Rizvi, Sayed Aliul H

    2010-01-01

    The effects of human age, type of computer, and noise on computer operators' performance of a data entry task were investigated. Twenty male subjects aged 10-55 were assigned into 4 age groups each consisting of 5 persons. They performed the task for 15 min on desktop and laptop computers in a sitting posture under varying levels of noise. The mean number of characters entered per minute (MNCEPM) was statistically analyzed. Operators in the 16-25 age group achieved the highest rate of data entry at each level of noise investigated. Operators performed better on desktop than on laptop computers. Their performance decreased when noise level increased from 82 to 92 dB(A), but it improved at 102 dB(A). The effects of age and noise were statistically significant. However, the effects of the type of computer, the interactions between age and type of computer, age and noise level, and type of computer and noise were not found to be statistically significant.

  9. Influence of sinogram affirmed iterative reconstruction of CT data on image noise characteristics and low-contrast detectability: an objective approach.

    Directory of Open Access Journals (Sweden)

    Christian von Falck

    Full Text Available OBJECTIVES: To utilize a novel objective approach combining a software phantom and an image quality metric to systematically evaluate the influence of sinogram affirmed iterative reconstruction (SAFIRE of multidetector computed tomography (MDCT data on image noise characteristics and low-contrast detectability (LCD. MATERIALS AND METHODS: A low-contrast and a high-contrast phantom were examined on a 128-slice scanner at different dose levels. The datasets were reconstructed using filtered back projection (FBP and SAFIRE and virtual low-contrast lesions (-20HU were inserted. LCD was evaluated using the multiscale structural similarity index (MS-SIM*. Image noise texture and spatial resolution were objectively evaluated. RESULTS: The use of SAFIRE led to an improvement of LCD for all dose levels and lesions sizes. The relative improvement of LCD was inversely related to the dose level, declining from 208%(±37%, 259%(±30% and 309%(±35% at 25mAs to 106%(±6%, 119%(±9% and 123%(±8% at 200mAs for SAFIRE filter strengths of 1, 3 and 5 (p<0.05. SAFIRE reached at least the LCD of FBP at a relative dose of 50%. There was no statistically significant difference in spatial resolution. The use of SAFIRE led to coarser image noise granularity. CONCLUSION: A novel objective approach combining a software phantom and the MS-SSIM* image quality metric was used to analyze the detectability of virtual low-contrast lesions against the background of image noise as created using SAFIRE in comparison to filtered back-projection. We found, that image noise characteristics using SAFIRE at 50% dose were comparable to the use of FBP at 100% dose with respect to lesion detectability. The unfamiliar imaging appearance of iteratively reconstructed datasets may in part be explained by a different, coarser noise characteristic as demonstrated by a granulometric analysis.

  10. The Influence of Optical Filtering on the Noise Performance of Microwave Photonic Phase Shifters Based on SOAs

    DEFF Research Database (Denmark)

    Lloret, Juan; Ramos, Francisco; Xue, Weiqi

    2011-01-01

    Different optical filtering scenarios involving microwave photonic phase shifters based on semiconductor optical amplifiers are investigated numerically as well as experimentally with respect to noise performance. Investigations on the role of the modulation depth and number of elements in cascaded...... shifting stages are also carried out. Suppression of the noise level by more than 5 dB has been achieved in schemes based on band-pass optical filtering when three phase shifting stages are cascaded....

  11. Human and animal sounds influence recognition of body language.

    Science.gov (United States)

    Van den Stock, Jan; Grèzes, Julie; de Gelder, Beatrice

    2008-11-25

    In naturalistic settings emotional events have multiple correlates and are simultaneously perceived by several sensory systems. Recent studies have shown that recognition of facial expressions is biased towards the emotion expressed by a simultaneously presented emotional expression in the voice even if attention is directed to the face only. So far, no study examined whether this phenomenon also applies to whole body expressions, although there is no obvious reason why this crossmodal influence would be specific for faces. Here we investigated whether perception of emotions expressed in whole body movements is influenced by affective information provided by human and by animal vocalizations. Participants were instructed to attend to the action displayed by the body and to categorize the expressed emotion. The results indicate that recognition of body language is biased towards the emotion expressed by the simultaneously presented auditory information, whether it consist of human or of animal sounds. Our results show that a crossmodal influence from auditory to visual emotional information obtains for whole body video images with the facial expression blanked and includes human as well as animal sounds.

  12. The influence of recombination on human genetic diversity.

    Directory of Open Access Journals (Sweden)

    Chris C A Spencer

    2006-09-01

    Full Text Available In humans, the rate of recombination, as measured on the megabase scale, is positively associated with the level of genetic variation, as measured at the genic scale. Despite considerable debate, it is not clear whether these factors are causally linked or, if they are, whether this is driven by the repeated action of adaptive evolution or molecular processes such as double-strand break formation and mismatch repair. We introduce three innovations to the analysis of recombination and diversity: fine-scale genetic maps estimated from genotype experiments that identify recombination hotspots at the kilobase scale, analysis of an entire human chromosome, and the use of wavelet techniques to identify correlations acting at different scales. We show that recombination influences genetic diversity only at the level of recombination hotspots. Hotspots are also associated with local increases in GC content and the relative frequency of GC-increasing mutations but have no effect on substitution rates. Broad-scale association between recombination and diversity is explained through covariance of both factors with base composition. To our knowledge, these results are the first evidence of a direct and local influence of recombination hotspots on genetic variation and the fate of individual mutations. However, that hotspots have no influence on substitution rates suggests that they are too ephemeral on an evolutionary time scale to have a strong influence on broader scale patterns of base composition and long-term molecular evolution.

  13. Quantifying the Influence of Climate on Human Conflict

    Science.gov (United States)

    Hsiang, S. M.; Burke, M.; Miguel, E.

    2014-12-01

    A rapidly growing body of research examines whether human conflict can be affected by climatic changes. Drawing from archaeology, criminology, economics, geography, history, political science, and psychology, we assemble and analyze the most rigorous quantitative studies and document, for the first time, a striking convergence of results. We find strong causal evidence linking climatic events to human conflict across a range of spatial and temporal scales and across all major regions of the world. The magnitude of climate's influence is substantial: for each one standard deviation (1sd) change in climate toward warmer temperatures or more extreme rainfall, median estimates indicate that the frequency of interpersonal violence rises 4% and the frequency of intergroup conflict rises 14%. Because locations throughout the inhabited world are expected to warm 2sd to 4sd by 2050, amplified rates of human conflict could represent a large and critical impact of anthropogenic climate change.

  14. The impact of human perception of simultaneous exposure to thermal load, low-frequency ventilation noise and indoor air pollution

    DEFF Research Database (Denmark)

    Alm, Ole; Witterseh, Thomas; Clausen, Geo

    1999-01-01

    Human perception of simultaneous exposure to combinations of three different levels of operative temperature, low-frequency ventilation noise and indoor air pollution (27 combinations) was studied in climate chambers. The operative temperatures studied were: 26.0 deg.C, 27.6 deg.C and 29.6 deg.......C, and the sound pressure levels were: 45 dB(A), 48 dB(A) and 51 dB(A). The air pollution corresponding to these three levels of perceived air quality (at 26 deg.C) was: 1.1 decipol (dp), 2.4 dp and 4.5 dp. A 1 deg.C change in operative temperature had the same impact on the human perception of the overall...... conditions as a change of 3.8 dB(A) in sound pressure level or a change of 7 dp in air pollution (at 26 deg.C). The percentage of dissatisfied with the perceived air quality increased with increasing temperature. An elevated temperature had a dominant impact on the human perception of the indoor environment...

  15. The impact of human perception of simultaneous exposure to thermal load, low-frequency ventilation noise and indoor air pollution

    DEFF Research Database (Denmark)

    Alm, Ole; Witterseh, Thomas; Clausen, Geo

    1999-01-01

    Human perception of simultaneous exposure to combinations of three different levels of operative temperature, low-frequency ventilation noise and indoor air pollution (27 combinations) was studied in climate chambers. The operative temperatures studied were: 26.0 deg.C, 27.6 deg.C and 29.6 deg.......C, and the sound pressure levels were: 45 dB(A), 48 dB(A) and 51 dB(A). The air pollution corresponding to these three levels of perceived air quality (at 26 deg.C) was: 1.1 decipol (dp), 2.4 dp and 4.5 dp. A 1 deg.C change in operative temperature had the same impact on the human perception of the overall...... conditions as a change of 3.8 dB(A) in sound pressure level or a change of 7 dp in air pollution (at 26 deg.C). The percentage of dissatisfied with the perceived air quality increased with increasing temperature. An elevated temperature had a dominant impact on the human perception of the indoor environment...

  16. Common genetic variants influence human subcortical brain structures

    Science.gov (United States)

    Hibar, Derrek P.; Stein, Jason L.; Renteria, Miguel E.; Arias-Vasquez, Alejandro; Desrivières, Sylvane; Jahanshad, Neda; Toro, Roberto; Wittfeld, Katharina; Abramovic, Lucija; Andersson, Micael; Aribisala, Benjamin S.; Armstrong, Nicola J.; Bernard, Manon; Bohlken, Marc M.; Boks, Marco P.; Bralten, Janita; Brown, Andrew A.; Chakravarty, M. Mallar; Chen, Qiang; Ching, Christopher R. K.; Cuellar-Partida, Gabriel; den Braber, Anouk; Giddaluru, Sudheer; Goldman, Aaron L.; Grimm, Oliver; Guadalupe, Tulio; Hass, Johanna; Woldehawariat, Girma; Holmes, Avram J.; Hoogman, Martine; Janowitz, Deborah; Jia, Tianye; Kim, Sungeun; Klein, Marieke; Kraemer, Bernd; Lee, Phil H.; Olde Loohuis, Loes M.; Luciano, Michelle; Macare, Christine; Mather, Karen A.; Mattheisen, Manuel; Milaneschi, Yuri; Nho, Kwangsik; Papmeyer, Martina; Ramasamy, Adaikalavan; Risacher, Shannon L.; Roiz-Santiañez, Roberto; Rose, Emma J.; Salami, Alireza; Sämann, Philipp G.; Schmaal, Lianne; Schork, Andrew J.; Shin, Jean; Strike, Lachlan T.; Teumer, Alexander; van Donkelaar, Marjolein M. J.; van Eijk, Kristel R.; Walters, Raymond K.; Westlye, Lars T.; Whelan, Christopher D.; Winkler, Anderson M.; Zwiers, Marcel P.; Alhusaini, Saud; Athanasiu, Lavinia; Ehrlich, Stefan; Hakobjan, Marina M. H.; Hartberg, Cecilie B.; Haukvik, Unn K.; Heister, Angelien J. G. A. M.; Hoehn, David; Kasperaviciute, Dalia; Liewald, David C. M.; Lopez, Lorna M.; Makkinje, Remco R. R.; Matarin, Mar; Naber, Marlies A. M.; McKay, D. Reese; Needham, Margaret; Nugent, Allison C.; Pütz, Benno; Royle, Natalie A.; Shen, Li; Sprooten, Emma; Trabzuni, Daniah; van der Marel, Saskia S. L.; van Hulzen, Kimm J. E.; Walton, Esther; Wolf, Christiane; Almasy, Laura; Ames, David; Arepalli, Sampath; Assareh, Amelia A.; Bastin, Mark E.; Brodaty, Henry; Bulayeva, Kazima B.; Carless, Melanie A.; Cichon, Sven; Corvin, Aiden; Curran, Joanne E.; Czisch, Michael; de Zubicaray, Greig I.; Dillman, Allissa; Duggirala, Ravi; Dyer, Thomas D.; Erk, Susanne; Fedko, Iryna O.; Ferrucci, Luigi; Foroud, Tatiana M.; Fox, Peter T.; Fukunaga, Masaki; Gibbs, J. Raphael; Göring, Harald H. H.; Green, Robert C.; Guelfi, Sebastian; Hansell, Narelle K.; Hartman, Catharina A.; Hegenscheid, Katrin; Heinz, Andreas; Hernandez, Dena G.; Heslenfeld, Dirk J.; Hoekstra, Pieter J.; Holsboer, Florian; Homuth, Georg; Hottenga, Jouke-Jan; Ikeda, Masashi; Jack, Clifford R.; Jenkinson, Mark; Johnson, Robert; Kanai, Ryota; Keil, Maria; Kent, Jack W.; Kochunov, Peter; Kwok, John B.; Lawrie, Stephen M.; Liu, Xinmin; Longo, Dan L.; McMahon, Katie L.; Meisenzahl, Eva; Melle, Ingrid; Mohnke, Sebastian; Montgomery, Grant W.; Mostert, Jeanette C.; Mühleisen, Thomas W.; Nalls, Michael A.; Nichols, Thomas E.; Nilsson, Lars G.; Nöthen, Markus M.; Ohi, Kazutaka; Olvera, Rene L.; Perez-Iglesias, Rocio; Pike, G. Bruce; Potkin, Steven G.; Reinvang, Ivar; Reppermund, Simone; Rietschel, Marcella; Romanczuk-Seiferth, Nina; Rosen, Glenn D.; Rujescu, Dan; Schnell, Knut; Schofield, Peter R.; Smith, Colin; Steen, Vidar M.; Sussmann, Jessika E.; Thalamuthu, Anbupalam; Toga, Arthur W.; Traynor, Bryan J.; Troncoso, Juan; Turner, Jessica A.; Valdés Hernández, Maria C.; van ’t Ent, Dennis; van der Brug, Marcel; van der Wee, Nic J. A.; van Tol, Marie-Jose; Veltman, Dick J.; Wassink, Thomas H.; Westman, Eric; Zielke, Ronald H.; Zonderman, Alan B.; Ashbrook, David G.; Hager, Reinmar; Lu, Lu; McMahon, Francis J.; Morris, Derek W.; Williams, Robert W.; Brunner, Han G.; Buckner, Randy L.; Buitelaar, Jan K.; Cahn, Wiepke; Calhoun, Vince D.; Cavalleri, Gianpiero L.; Crespo-Facorro, Benedicto; Dale, Anders M.; Davies, Gareth E.; Delanty, Norman; Depondt, Chantal; Djurovic, Srdjan; Drevets, Wayne C.; Espeseth, Thomas; Gollub, Randy L.; Ho, Beng-Choon; Hoffmann, Wolfgang; Hosten, Norbert; Kahn, René S.; Le Hellard, Stephanie; Meyer-Lindenberg, Andreas; Müller-Myhsok, Bertram; Nauck, Matthias; Nyberg, Lars; Pandolfo, Massimo; Penninx, Brenda W. J. H.; Roffman, Joshua L.; Sisodiya, Sanjay M.; Smoller, Jordan W.; van Bokhoven, Hans; van Haren, Neeltje E. M.; Völzke, Henry; Walter, Henrik; Weiner, Michael W.; Wen, Wei; White, Tonya; Agartz, Ingrid; Andreassen, Ole A.; Blangero, John; Boomsma, Dorret I.; Brouwer, Rachel M.; Cannon, Dara M.; Cookson, Mark R.; de Geus, Eco J. C.; Deary, Ian J.; Donohoe, Gary; Fernández, Guillén; Fisher, Simon E.; Francks, Clyde; Glahn, David C.; Grabe, Hans J.; Gruber, Oliver; Hardy, John; Hashimoto, Ryota; Hulshoff Pol, Hilleke E.; Jönsson, Erik G.; Kloszewska, Iwona; Lovestone, Simon; Mattay, Venkata S.; Mecocci, Patrizia; McDonald, Colm; McIntosh, Andrew M.; Ophoff, Roel A.; Paus, Tomas; Pausova, Zdenka; Ryten, Mina; Sachdev, Perminder S.; Saykin, Andrew J.; Simmons, Andy; Singleton, Andrew; Soininen, Hilkka; Wardlaw, Joanna M.; Weale, Michael E.; Weinberger, Daniel R.; Adams, Hieab H. H.; Launer, Lenore J.; Seiler, Stephan; Schmidt, Reinhold; Chauhan, Ganesh; Satizabal, Claudia L.; Becker, James T.; Yanek, Lisa; van der Lee, Sven J.; Ebling, Maritza; Fischl, Bruce; Longstreth, W. T.; Greve, Douglas; Schmidt, Helena; Nyquist, Paul; Vinke, Louis N.; van Duijn, Cornelia M.; Xue, Luting; Mazoyer, Bernard; Bis, Joshua C.; Gudnason, Vilmundur; Seshadri, Sudha; Ikram, M. Arfan; Martin, Nicholas G.; Wright, Margaret J.; Schumann, Gunter; Franke, Barbara; Thompson, Paul M.; Medland, Sarah E.

    2015-01-01

    The highly complex structure of the human brain is strongly shaped by genetic influences1. Subcortical brain regions form circuits with cortical areas to coordinate movement2, learning, memory3 and motivation4, and altered circuits can lead to abnormal behaviour and disease2. To investigate how common genetic variants affect the structure of these brain regions, here we conduct genome-wide association studies of the volumes of seven subcortical regions and the intracranial volume derived from magnetic resonance images of 30,717 individuals from 50 cohorts. We identify five novel genetic variants influencing the volumes of the putamen and caudate nucleus. We also find stronger evidence for three loci with previously established influences on hippocampal volume5 and intracranial volume6. These variants show specific volumetric effects on brain structures rather than global effects across structures. The strongest effects were found for the putamen, where a novel intergenic locus with replicable influence on volume (rs945270; P = 1.08 × 10−33; 0.52% variance explained) showed evidence of altering the expression of the KTN1 gene in both brain and blood tissue. Variants influencing putamen volume clustered near developmental genes that regulate apoptosis, axon guidance and vesicle transport. Identification of these genetic variants provides insight into the causes of variability inhuman brain development, and may help to determine mechanisms of neuropsychiatric dysfunction. PMID:25607358

  17. Geo-spatial distribution of cloud cover and influence of cloud induced attenuation and noise temperature on satellite signal propagation over Nigeria

    Science.gov (United States)

    Ojo, Joseph Sunday

    2017-05-01

    The study of the influence of cloud cover on satellite propagation links is becoming more demanding due to the requirement of larger bandwidth for different satellite applications. Cloud attenuation is one of the major factors to consider for optimum performance of Ka/V and other higher frequency bands. In this paper, the geo-spatial distribution of cloud coverage over some chosen stations in Nigeria has been considered. The substantial scale spatial dispersion of cloud cover based on synoptic meteorological data and the possible impact on satellite communication links at higher frequency bands was also investigated. The investigation was based on 5 years (2008-2012) achieved cloud cover data collected by the Nigerian Meteorological Agency (NIMET) Federal Ministry of Aviation, Oshodi Lagos over four synoptic hours of the day covering day and night. The performances of satellite signals as they traverse through the cloud and cloud noise temperature at different seasons and over different hours of days at Ku/W-bands frequency are also examined. The overall result shows that the additional total atmospheric noise temperature due to the clear air effect and the noise temperature from the cloud reduces the signal-to-noise ratio of the satellite receiver systems, leading to more signal loss and if not adequately taken care of may lead to significant outage. The present results will be useful for Earth-space link budgeting, especially for the proposed multi-sensors communication satellite systems in Nigeria.

  18. Human influences on water quality in Great Lakes coastal wetlands.

    Science.gov (United States)

    Morrice, John A; Danz, Nicholas P; Regal, Ronald R; Kelly, John R; Niemi, Gerald J; Reavie, Euan D; Hollenhorst, Tom; Axler, Richard P; Trebitz, Anett S; Cotter, Anne M; Peterson, Gregory S

    2008-03-01

    A better understanding of relationships between human activities and water chemistry is needed to identify and manage sources of anthropogenic stress in Great Lakes coastal wetlands. The objective of the study described in this article was to characterize relationships between water chemistry and multiple classes of human activity (agriculture, population and development, point source pollution, and atmospheric deposition). We also evaluated the influence of geomorphology and biogeographic factors on stressor-water quality relationships. We collected water chemistry data from 98 coastal wetlands distributed along the United States shoreline of the Laurentian Great Lakes and GIS-based stressor data from the associated drainage basin to examine stressor-water quality relationships. The sampling captured broad ranges (1.5-2 orders of magnitude) in total phosphorus (TP), total nitrogen (TN), dissolved inorganic nitrogen (DIN), total suspended solids (TSS), chlorophyll a (Chl a), and chloride; concentrations were strongly correlated with stressor metrics. Hierarchical partitioning and all-subsets regression analyses were used to evaluate the independent influence of different stressor classes on water quality and to identify best predictive models. Results showed that all categories of stress influenced water quality and that the relative influence of different classes of disturbance varied among water quality parameters. Chloride exhibited the strongest relationships with stressors followed in order by TN, Chl a, TP, TSS, and DIN. In general, coarse scale classification of wetlands by morphology (three wetland classes: riverine, protected, open coastal) and biogeography (two ecoprovinces: Eastern Broadleaf Forest [EBF] and Laurentian Mixed Forest [LMF]) did not improve predictive models. This study provides strong evidence of the link between water chemistry and human stress in Great Lakes coastal wetlands and can be used to inform management efforts to improve water

  19. Beneficial or harmful influence of phytosterols on human cells?

    Science.gov (United States)

    Rubis, Blazej; Paszel, Anna; Kaczmarek, Mariusz; Rudzinska, Magdalena; Jelen, Henryk; Rybczynska, Maria

    2008-12-01

    So far, a protective influence of phytosterols on the human organism and atherogenesis has been suggested. Most studies have concentrated on the cytotoxic efficacy of phytosterols on cancer cells. However, there are only a few reports showing their influence on normal cells. The aim of the present study was to determine whether dietary plant sterols and their thermal processing products could influence the viability of normal, abdominal endothelial cells that play a crucial role in atherogenesis. Thus, we studied the effect of rapeseed oil-extract components, beta-sitosterol, cholesterol and their epoxy-derivatives, 5 alpha,6 alpha-epoxy-beta-sitosterol and 5 alpha,6 alpha-epoxycholesterol, on the proliferation and viability of human abdominal aorta endothelial cells HAAE-2 in vitro. We showed strong cytotoxic properties of beta-sitosterol in HAAE-2 cells (half maximal inhibitory concentration (IC50) = 1.99 (SEM 0.56) microm) and, interestingly, a weaker cytotoxic effect of 5 alpha,6 alpha-epoxy-beta-sitosterol (IC50>200 microm). Moreover, we observed a significantly stronger cytotoxic activity of beta-sitosterol than cholesterol (IC50 = 8.99 (SEM 2.74) microm). We also revealed that beta-sitosterol as well as cholesterol caused apoptosis, inducing caspase-3 activity in the cells (60 % increase compared with control cells) that corresponded to the DNA fragmentation analysis in a terminal uridine deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labelling (TUNEL) study. Although absorption of plant sterols is low compared with cholesterol, they can still influence other physiological functions. Since they effectively reduce serum LDL-cholesterol and atherosclerotic risk but also decrease the viability of cancer cells as well as normal cells in a time- and dose-dependent manner in vitro, their influence on other metabolic processes remains to be elucidated.

  20. Human detection and ranging at long range and through light foliage using a W-band noise radar with an embedded tone

    Science.gov (United States)

    Gallagher, Kyle A.; Narayanan, Ram M.

    2013-05-01

    This paper describes a millimeter-wave (mm-wave) radar system that has been used to range humans concealed in light foliage at 30 meters and range exposed humans at distances up to 213 meters. Human micro-Doppler is also detected through light foliage at 30 meters and up to 90 meters when no foliage is present. This is done by utilizing a composite signal consisting of two waveforms: a wide-band noise waveform and a single tone. These waveforms are summed together and transmitted simultaneously. Matched filtering of the received and transmitted noise signals is performed to range targets with high resolution, while the received single tone signal is used for Doppler analysis. The Doppler measurements are used to distinguish between different human movements using characteristic micro-Doppler signals. Using hardware and software filters allows for simultaneous processing of both the noise and Doppler waveforms. Our measurements establish the mm-wave system's ability to range humans up to 213 meters and distinguish between different human movements at 90 meters. The radar system was also tested through light foliage. In this paper, we present results on human target ranging and Doppler characterization of human movements.

  1. A Possible Model of Noise Enhanced Visual Perception in Human Vision

    CERN Document Server

    Kundu, Ajanta

    2010-01-01

    We demonstrate, through simulation, that a simple centre surround receptive field of vision is capable of exhibiting stochastic resonance. We also show that this could be used to model the nature of contrast sensitivity enhancement of human vision, through stochastic resonance, observed in psychophysical experiments.

  2. Attribution of observed surface humidity changes to human influence.

    Science.gov (United States)

    Willett, Katharine M; Gillett, Nathan P; Jones, Philip D; Thorne, Peter W

    2007-10-11

    Water vapour is the most important contributor to the natural greenhouse effect, and the amount of water vapour in the atmosphere is expected to increase under conditions of greenhouse-gas-induced warming, leading to a significant feedback on anthropogenic climate change. Theoretical and modelling studies predict that relative humidity will remain approximately constant at the global scale as the climate warms, leading to an increase in specific humidity. Although significant increases in surface specific humidity have been identified in several regions, and on the global scale in non-homogenized data, it has not been shown whether these changes are due to natural or human influences on climate. Here we use a new quality-controlled and homogenized gridded observational data set of surface humidity, with output from a coupled climate model, to identify and explore the causes of changes in surface specific humidity over the late twentieth century. We identify a significant global-scale increase in surface specific humidity that is attributable mainly to human influence. Specific humidity is found to have increased in response to rising temperatures, with relative humidity remaining approximately constant. These changes may have important implications, because atmospheric humidity is a key variable in determining the geographical distribution and maximum intensity of precipitation, the potential maximum intensity of tropical cyclones, and human heat stress, and has important effects on the biosphere and surface hydrology.

  3. Exploring possible human influences on the evolution of Darwin's finches.

    Science.gov (United States)

    De León, Luis Fernando; Raeymaekers, Joost A M; Bermingham, Eldredge; Podos, Jeffrey; Herrel, Anthony; Hendry, Andrew P

    2011-08-01

    Humans are an increasingly common influence on the evolution of natural populations. Potential arenas of influence include altered evolutionary trajectories within populations and modifications of the process of divergence among populations. We consider this second arena in the medium ground finch (Geospiza fortis) on Santa Cruz Island, Galápagos, Ecuador. Our study compared the G. fortis population at a relatively undisturbed site, El Garrapatero, to the population at a severely disturbed site, Academy Bay, which is immediately adjacent to the town of Puerto Ayora. The El Garrapatero population currently shows beak size bimodality that is tied to assortative mating and disruptive selection, whereas the Academy Bay population was historically bimodal but has lost this property in conjunction with a dramatic increase in local human population density. We here evaluate potential ecological-adaptive drivers of the differences in modality by quantifying relationships between morphology (beak and head dimensions), functional performance (bite force), and environmental characteristics (diet). Our main finding is that associations among these variables are generally weaker at Academy Bay than at El Garrapatero, possibly because novel foods are used at the former site irrespective of individual morphology and performance. These results are consistent with the hypothesis that the rugged adaptive landscapes promoting and maintaining diversification in nature can be smoothed by human activities, thus hindering ongoing adaptive radiation.

  4. The Influence of Nonlinearity, Noise and Extinction Ratio on the Cascading Properties of 2R-Regenerators

    DEFF Research Database (Denmark)

    Öhman, Filip; Mørk, Jesper

    2005-01-01

    We have derived an expression for the BER of a cascade of 2R-regenerators including the effects of nonlinearity, noise and extinction-ratio. The best choice of threshold and the interplay bet1-55752-770-9ween device parameters are investigated.......We have derived an expression for the BER of a cascade of 2R-regenerators including the effects of nonlinearity, noise and extinction-ratio. The best choice of threshold and the interplay bet1-55752-770-9ween device parameters are investigated....

  5. Near-infrared transmission spectroscopy of aqueous solutions: The influence of optical pathlength on signal-to-noise ratio

    DEFF Research Database (Denmark)

    Jensen, P.S.; Bak, J.

    2002-01-01

    The optimal choice of optical pathlength, source intensity, and detector for near-infrared transmission measurements of trace components in aqueous solutions depends on the strong absorption of water. In this study we examine under which experimental circumstances one may increase the pathlength...... to obtain a measurement with higher signal-to-noise ratio. The noise level of measurements at eight different pathlengths from 0.2 to 2.0 mm of pure water and of 1 g/dL aqueous glucose signals were measured using a Fourier transform near-infrared spectrometer and a variable pathlength transmission cell...

  6. Demonstration of brain noise on human EEG signals in perception of bistable images

    Science.gov (United States)

    Grubov, Vadim V.; Runnova, Anastasiya E.; Kurovskaya, Maria K.; Pavlov, Alexey N.; Koronovskii, Alexey A.; Hramov, Alexander E.

    2016-03-01

    In this report we studied human brain activity in the case of bistable visual perception. We proposed a new approach for quantitative characterization of this activity based on analysis of EEG oscillatory patterns and evoked potentials. Accordingly to theoretical background, obtained experimental EEG data and results of its analysis we studied a characteristics of brain activity during decision-making. Also we have shown that decisionmaking process has the special patterns on the EEG data.

  7. Functional Architecture of Noise Correlations in Human Early Visual Cortex and its Relationship with Coherent Spontaneous Activity

    Directory of Open Access Journals (Sweden)

    Jungwon Ryu

    2012-10-01

    Full Text Available Responses of single sensory neurons to stimuli are ‘noisy’, varying substantially across repeated trials of identical stimulation. Intriguingly, these individual ‘noise responses’ (NR—deviations from their means—are not isolated; rather they are highly correlated, referred to as ‘noise correlation’ (NC. From a computational viewpoint, the presence and nature of NC exert great impacts on the information processing capacity of neurons as they encode sensory events as a population, decode those encoded neural responses, and contribute to perceptual choices for action. Regarding the origin of NR, on the other hand, there has been growing evidence pointing to its tight linkage with ‘spontaneous responses’ (SR—fluctuations of neural activity in the absence of external input or tasks. To investigate the functional structure of NC and its relationship with ‘correlations in SR’ (SC, we defined population receptive fields (pRFs of unit volumes of gray matter (UV in human early visual cortex and computed NRs and SRs using fMRI. NC increased with an increasing degree of similarity in pRF tuning properties such as orientation, spatial frequency, and visuotopic position, particularly between UV pairs close in cortical distance. This ‘like-to-like’ structure of NC remained unaltered across scan runs with different stimuli, even among between-area UV pairs. SC was higher than NC, and its functional and temporal structures were quite similar to those of NC. Furthermore, the partial correlation analysis revealed that NC between a given pair of UVs was best predicted by their SC than by any other factors examined in the current study.

  8. Mapping genetic influences on the corticospinal motor system in humans

    DEFF Research Database (Denmark)

    Cheeran, B J; Ritter, C; Rothwell, J C

    2009-01-01

    It is becoming increasingly clear that genetic variations account for a certain amount of variance in the acquisition and maintenance of different skills. Until now, several levels of genetic influences were examined, ranging from global heritability estimates down to the analysis...... of the contribution of single nucleotide polymorphisms (SNP) and variable number tandem repeats. In humans, the corticospinal motor system is essential to the acquisition of fine manual motor skills which require a finely tuned coordination of activity in distal forelimb muscles. Here we review recent brain mapping...

  9. Influence of prebiotics on the human immune system (GALT).

    Science.gov (United States)

    Bodera, Pawel

    2008-06-01

    Prebiotics have great potential to improve human health in specific intestinal disorders. The knowledge about the influence of prebiotics on the gut-associated lymphoid tissues (GALT) for the improvement of human health is still growing. This paper reviews the latest evidence for the immunity-enhancing effects of prebiotics. Prebiotics, include inulin, fructooligosaccharides, mannosoligosaccharides, and arabinogalactans, are a therapeutic nutritional preparation used for the gut function favoring growth of normal bacterial flora and impedes growth of pathogenic organisms. There is convincing preliminary data to suggest that the consumption of prebiotics can modulate immune parameters in GALT, secondary lymphoid tissues and peripheral circulation. There is increasing evidence that the newly described prebiotics and innovative means of administration can modulate various properties of the immune system, including those of the gut-associated lymphoid tissues (GALT). Authors of recently published patents showed new mechanisms for immuno-modulation, and the ultimate impact on immunological health of prebiotics.

  10. Using eye movements for analyzing the influence of linguistic complexity, noise, and hearing loss on sentence processing time

    DEFF Research Database (Denmark)

    Wendt, Dorothea; Müller, Jana; Kollmeier, Birger;

    2015-01-01

    and compares the ET method to electrooculography (EOG). The processing time of sentences with different linguistic complexity was measured in quiet and in modulated noise using ET and EOG simultaneously. Eleven participants with hearing impairment and five participants with normal hearing participated...

  11. The influence of lexical-access ability and vocabulary knowledge on measures of speech recognition in noise.

    Science.gov (United States)

    Kaandorp, Marre W; De Groot, Annette M B; Festen, Joost M; Smits, Cas; Goverts, S Theo

    2016-01-01

    The main objective was to investigate the effect of linguistic abilities (lexical-access ability and vocabulary size) on different measures of speech-in-noise recognition in normal-hearing listeners with various levels of language proficiency. Speech reception thresholds (SRTs) were measured for sentences in steady-state (SRTstat) and fluctuating noise (SRTfluc), and for digit-triplets in steady-state noise (DIN). Lexical-access ability was measured with a lexical-decision test and a word-naming test. Vocabulary size was also measured. For the SRT, keyword scoring and sentence scoring were compared. To introduce variation in linguistic abilities, three groups of 24 young normal-hearing listeners were included: higher-educated native, lower-educated native, and higher-educated non-native listeners. Lexical-access ability was most accurately measured with combined results of lexical decision and word naming. Lexical-access ability explained 60% of the variance in SRT. The effect of linguistic abilities on SRTs was up to 5.6 dB for SRTstat and 8 dB for SRTfluc. Using keyword scoring reduced this effect by approximately 1.5 dB. For DIN the effect of linguistic ability was less than 1 dB. Lexical-access ability is an important predictor of SRTs in normal-hearing listeners. These results are important to consider in the interpretation of speech-in-noise scores of hearing-impaired listeners.

  12. Network Analysis of Human Genes Influencing Susceptibility to Mycobacterial Infections.

    Directory of Open Access Journals (Sweden)

    Ettie M Lipner

    Full Text Available Tuberculosis and nontuberculous mycobacterial infections constitute a high burden of pulmonary disease in humans, resulting in over 1.5 million deaths per year. Building on the premise that genetic factors influence the instance, progression, and defense of infectious disease, we undertook a systems biology approach to investigate relationships among genetic factors that may play a role in increased susceptibility or control of mycobacterial infections. We combined literature and database mining with network analysis and pathway enrichment analysis to examine genes, pathways, and networks, involved in the human response to Mycobacterium tuberculosis and nontuberculous mycobacterial infections. This approach allowed us to examine functional relationships among reported genes, and to identify novel genes and enriched pathways that may play a role in mycobacterial susceptibility or control. Our findings suggest that the primary pathways and genes influencing mycobacterial infection control involve an interplay between innate and adaptive immune proteins and pathways. Signaling pathways involved in autoimmune disease were significantly enriched as revealed in our networks. Mycobacterial disease susceptibility networks were also examined within the context of gene-chemical relationships, in order to identify putative drugs and nutrients with potential beneficial immunomodulatory or anti-mycobacterial effects.

  13. The noise spectrum influence on Noise-Induced Hearing Loss prevalence in workers A influência do espectro de ruído na prevalência de Perda Auditiva Induzida por Ruído em trabalhadores

    Directory of Open Access Journals (Sweden)

    Marlene Escher Boger

    2009-06-01

    Full Text Available Noise Induced Hearing Loss (NIHL is an insidious and cumulative disease that worsens over the years with work-related noise exposure. AIM: To evaluate the noise spectrum influence on NIHL prevalence in workers. MATERIALS AND METHODS: This a cross-sectional historical cohort carried out in steel mills, lumber mills and marble shops, with noise levels above 85dB, in which we evaluated the auditory thresholds for frequencies from 250Hz to 8,000Hz. To evaluate the work environment, we observed the entire setting, aiming at checking sound intensities in an eighth frequency filter. RESULTS: We carried out 192 hearing threshold evaluations after an occupational anamnesis. Concerning NIHL, we noticed that 49% of the audiometry results presented hearing deterioration in the acute frequencies. We studied the mean values and standard deviations for frequencies over 3,000Hz, in all workers, and we observed that the highest average values were in the frequency of 6,000Hz. We did not notice any association among frequency bands carrying intense noise levels and the hearing damage frequency. CONCLUSION: Noise intensity seems to be the main risk factor for loss hearing, regardless of frequency range.A Perda Auditiva Induzida por Ruído (PAIR é uma doença insidiosa cumulativa, que cresce ao longo dos anos de exposição ao ruído associado ao ambiente de trabalho. OBJETIVO: Avaliar a influência do espectro de ruído na prevalência de PAIR em trabalhadores. MATERIAL E MÉTODO: Trata-se de estudo de coorte histórica com corte transversal realizado em indústrias metalúrgicas, madeireiras e marmorarias, com níveis de ruído acima de 85dB, nas quais avaliou-se o limiar auditivo para as frequências de 250Hz a 8.000Hz. Na avaliação ambiental verificou-se a distribuição da intensidade sonora em filtro de frequência de oitava. RESULTADOS: Foram realizadas 192 avaliações do limiar auditivo precedidas de anamnese ocupacional. Em relação à PAIR observou

  14. The influence of human papillomavirus on nasopharyngeal carcinoma in Japan.

    Science.gov (United States)

    Kano, Makoto; Kondo, Satoru; Wakisaka, Naohiro; Moriyama-Kita, Makiko; Nakanishi, Yosuke; Endo, Kazuhira; Murono, Shigeyuki; Nakamura, Hiroyuki; Yoshizaki, Tomokazu

    2017-06-01

    Although Japan is a non-endemic area with nasopharyngeal carcinoma (NPC), the proportion of WHO type I NPC in Japan are different from that in non-endemic areas such as North America and Europe. Recently, it is said that not only Epstein-Barr virus (EBV) but also human papillomavirus (HPV) has an influence on NPC in non-endemic areas. The aim of this study is to clarify the influence of HPV on NPC in Japan. Paraffin-embedded tumor specimens were available for 59 patients with NPC diagnosed between 1996 and 2015. We detected the virus status by p16 immunohistochemistry, HPV PCR, and in situ hybridization for Epstein-Barr virus (EBV)-encoded RNA. Kaplan-Meier curves were used to compare the overall survival by viral status. Among the 59 patients, 49 (83%) were EBV-positive/HPV-negative, 2 (3%) were EBV-positive/HPV-positive, and 8 (16%) were EBV-negative/HPV-negative. All HPV-positive NPCs were co-infected with EBV. There were no significant differences between the overall survival in the three groups (p=0.111). In Japan, HPV was detected in a few patients with NPC, and we suggest that HPV has no influence on NPC carcinogenesis in this population. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  15. 井下噪声对人心理生理影响分析%Impact of underground noise on human physiology and psychology

    Institute of Scientific and Technical Information of China (English)

    程根银; 陈绍杰; 魏志勇; 贺飞

    2011-01-01

    为了研究井下噪声对作业人员心理生理的影响,探究井下噪声的危害,通过对某矿井下作业人员问卷调查,用统计数据去分析噪声对作业人员的影响.分析结果表明:井下噪声对作业人员的影响是由年龄、工龄、作业区综合影响的结果,只从单一因素考虑噪声对井下人员的影响是不全面的;噪声对井下作业人员的影响,不仅与年龄、工龄有关,还因作业区间的不同而不同.井下噪声对心理的影响主要是使作业人员产生烦躁情绪,对生理的影响主要包括对听觉、消化系统、神经系统、内分泌系统等系统的影响.%In order to study the effects of underground noise on workers' physiology and psychology and investigate the harm of underground noise, according to questionnaire survey for work personnel in some underground coal mine, the influence of noise on workers is analyzed with the statistical data, and the analysis results indicate that the influence of underground noise on working personnel is a result of the combined effects of age, length of service, and work areas, and moreover the longer age of work is more serious effects; furthermore it is not perfect that take into account upon the influence on underground personnel according to only one signal factor. The influence "of noise on workers not only has something to do with age and length of service, but also depends on the working areas. The major influence of noise on workers' physiology refers to the work personnel suffering from irritable feeling, and the influence on workers' psychology mainly include auditory system, digestive system, nervous system, endocrine system and other systems.

  16. Detector of Optical Vortices as the Main Element of the System of Data Transfer: Principles of Operation, Numerical Model, and Influence of Noise and Atmospheric Turbulence

    Directory of Open Access Journals (Sweden)

    Valerii Aksenov

    2012-01-01

    Full Text Available The method is proposed of optical vortex topological charge detection along with a design of a corresponding detector. The developed technique is based on measurements of light field intensity. Mathematical model simulating performance of the detector is described in the paper, and results of numerical experiments are presented which illustrate recognition of a vortex in a turbulent medium and in the presence of amplitude and phase noise in the registered radiation. Influence of shifts of the system optical axis on precision of registration is also considered in the paper.

  17. Practical ranges of loudness levels of various types of environmental noise, including traffic noise, aircraft noise, and industrial noise

    NARCIS (Netherlands)

    Salomons, E.M.; Janssen, S.A.

    2011-01-01

    In environmental noise control one commonly employs the A-weighted sound level as an approximate measure of the effect of noise on people. A measure that is more closely related to direct human perception of noise is the loudness level. At constant A-weighted sound level, the loudness level of a noi

  18. Comprehensive study of CD compensation and carrier phase estimation in optical communication systems influenced by equalization enhanced phase noise

    CERN Document Server

    Xu, Tianhua; Popov, Sergei; Li, Jie; Sergeyev, Sergey; Friberg, Ari T; Liu, Tiegen; Zhang, Yimo

    2016-01-01

    The performance of long-haul coherent optical fiber transmission system is significantly affected by the equalization enhanced phase noise (EEPN), due to the interaction between the electronic dispersion compensation (EDC) and the laser phase noise. In this paper, we present a comprehensive study on different chromatic dispersion (CD) compensation and carrier phase recovery (CPR) approaches, in the n-level phase shift keying (n-PSK) and the n-level quadrature amplitude modulation (n-QAM) coherent optical transmission systems, considering the impacts of EEPN. Four CD compensation methods are considered: the time-domain equalization (TDE), the frequency-domain equalization (FDE), the least mean square (LMS) adaptive equalization are applied for EDC, and the dispersion compensating fiber (DCF) is employed for optical dispersion compensation (ODC). Meanwhile, three carrier phase recovery methods are also involved: a one-tap normalized least mean square (NLMS) algorithm, a block-wise average (BWA) algorithm, and a...

  19. Influence of boat noises on escape behaviour of white-spotted eagle ray Aetobatus ocellatus at Moorea Island (French Polynesia).

    Science.gov (United States)

    Berthe, Cecile; Lecchini, David

    2016-02-01

    The present study tested different sounds that could disturb eagle rays (Aetobatus ocellatus) during their foraging activities at Moorea, French Polynesia. Results showed that artificial white sound and single-frequency tones (40 Hz, 600 Hz or 1 kHz) did not have an effect on rays (at least 90% of rays continued to forage over sand), while playbacks of boat motor sound significantly disturbed rays during foraging activity (60% exhibited an escape behaviour). Overall, our study highlighted the negative effect of boat noises on the foraging activity of eagle rays. These noises produced by boat traffic could, however, have some positive effects for marine aquaculture if they could be used as a deterrent to repel the eagle rays, main predators of the pearl oysters.

  20. Influence of sensory neuropeptides on human cutaneous wound healing process.

    Science.gov (United States)

    Chéret, J; Lebonvallet, N; Buhé, V; Carre, J L; Misery, L; Le Gall-Ianotto, C

    2014-06-01

    Close interactions exist between primary sensory neurons of the peripheral nervous system (PNS) and skin cells. The PNS may be implicated in the modulation of different skin functions as wound healing. Study the influence of sensory neurons in human cutaneous wound healing. We incubated injured human skin explants either with rat primary sensory neurons from dorsal root ganglia (DRG) or different neuropeptides (vasoactive intestinal peptide or VIP, calcitonin gene-related peptide or CGRP, substance P or SP) at various concentrations. Then we evaluated their effects on the proliferative and extracellular matrix (ECM) remodeling phases, dermal fibroblasts adhesion and differentiation into myofibroblasts. Thus, DRG and all studied neuromediators increased fibroblasts and keratinocytes proliferation and act on the expression ratio between collagen type I and type III in favor of collagen I, particularly between the 3rd and 7th day of culture. Furthermore, the enzymatic activities of matrix metalloprotesases (MMP-2 and MMP-9) were increased in the first days of wound healing process. Finally, the adhesion of human dermal fibroblasts and their differentiation into myofibroblasts were promoted after incubation with neuromediators. Interestingly, the most potent concentrations for each tested molecules, were the lowest concentrations, corresponding to physiological concentrations. Sensory neurons and their derived-neuropeptides are able to promote skin wound healing. Copyright © 2014 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

  1. The efficacy of N-acetylcysteine to protect the human cochlea from subclinical hearing loss caused by impulse noise: A controlled trial

    Directory of Open Access Journals (Sweden)

    Ann-Cathrine Lindblad

    2011-01-01

    Full Text Available In military outdoor shooting training, with safety measures enforced, the risk of a permanent, noise-induced hearing loss is very small. But urban warfare training performed indoors, with reflections from walls, might increase the risk. A question is whether antioxidants can reduce the negative effects of noise on human hearing as it does on research animals. Hearing tests were performed on a control group of 23 military officers before and after a shooting session in a bunker-like room. The experiments were repeated on another group of 11 officers with peroral adminstration of N-acetyl-cysteine (NAC, directly after the shooting. The measurements performed were tone thresholds; transient-evoked otoacoustic emissions, with and without contralateral noise; and psycho-acoustical modulation transfer function (PMTF, thresholds for brief tones in modulated noise. Effects from shooting on hearing thresholds were small, but threshold behavior supports use of NAC treatment. On the PMTF, shooting without NAC gave strong effects. Those effects were like those from continuous noise, which means that strict safety measures should be enforced. The most striking finding was that the non-linearity of the cochlea, that was strongly reduced in the group without NAC, as manifested by the PMTF-results, was practically unchanged in the NAC-group throughout the study. NAC treatment directly after shooting in a bunkerlike room seems to give some protection of the cochlea.

  2. Simulating food web dynamics along a gradient: quantifying human influence.

    Directory of Open Access Journals (Sweden)

    Ferenc Jordán

    Full Text Available Realistically parameterized and dynamically simulated food-webs are useful tool to explore the importance of the functional diversity of ecosystems, and in particular relations between the dynamics of species and the whole community. We present a stochastic dynamical food web simulation for the Kelian River (Borneo. The food web was constructed for six different locations, arrayed along a gradient of increasing human perturbation (mostly resulting from gold mining activities along the river. Along the river, the relative importance of grazers, filterers and shredders decreases with increasing disturbance downstream, while predators become more dominant in governing eco-dynamics. Human activity led to increased turbidity and sedimentation which adversely impacts primary productivity. Since the main difference between the study sites was not the composition of the food webs (structure is quite similar but the strengths of interactions and the abundance of the trophic groups, a dynamical simulation approach seemed to be useful to better explain human influence. In the pristine river (study site 1, when comparing a structural version of our model with the dynamical model we found that structurally central groups such as omnivores and carnivores were not the most important ones dynamically. Instead, primary consumers such as invertebrate grazers and shredders generated a greater dynamical response. Based on the dynamically most important groups, bottom-up control is replaced by the predominant top-down control regime as distance downstream and human disturbance increased. An important finding, potentially explaining the poor structure to dynamics relationship, is that indirect effects are at least as important as direct ones during the simulations. We suggest that our approach and this simulation framework could serve systems-based conservation efforts. Quantitative indicators on the relative importance of trophic groups and the mechanistic modeling

  3. Simulating food web dynamics along a gradient: quantifying human influence.

    Science.gov (United States)

    Jordán, Ferenc; Gjata, Nerta; Mei, Shu; Yule, Catherine M

    2012-01-01

    Realistically parameterized and dynamically simulated food-webs are useful tool to explore the importance of the functional diversity of ecosystems, and in particular relations between the dynamics of species and the whole community. We present a stochastic dynamical food web simulation for the Kelian River (Borneo). The food web was constructed for six different locations, arrayed along a gradient of increasing human perturbation (mostly resulting from gold mining activities) along the river. Along the river, the relative importance of grazers, filterers and shredders decreases with increasing disturbance downstream, while predators become more dominant in governing eco-dynamics. Human activity led to increased turbidity and sedimentation which adversely impacts primary productivity. Since the main difference between the study sites was not the composition of the food webs (structure is quite similar) but the strengths of interactions and the abundance of the trophic groups, a dynamical simulation approach seemed to be useful to better explain human influence. In the pristine river (study site 1), when comparing a structural version of our model with the dynamical model we found that structurally central groups such as omnivores and carnivores were not the most important ones dynamically. Instead, primary consumers such as invertebrate grazers and shredders generated a greater dynamical response. Based on the dynamically most important groups, bottom-up control is replaced by the predominant top-down control regime as distance downstream and human disturbance increased. An important finding, potentially explaining the poor structure to dynamics relationship, is that indirect effects are at least as important as direct ones during the simulations. We suggest that our approach and this simulation framework could serve systems-based conservation efforts. Quantitative indicators on the relative importance of trophic groups and the mechanistic modeling of eco

  4. Influence of PAMAM dendrimers on the human insulin

    Science.gov (United States)

    Nowacka, Olga; Miłowska, Katarzyna; Ionov, Maksim; Bryszewska, Maria

    2015-12-01

    Dendrimers are specific class of polymeric macromolecules with wide spectrum of properties. One of the promising activities of dendrimers involves inhibition of protein fibril formation. Aggregation and fibrillation of insulin occurs in insulin-dependent diabetic patients after repeated administration, due to these processes being very easily triggered by the conditions of drug administration. The aim of this work was to study the influence of various generations PAMAM dendrimers on human insulin zeta potential, secondary structure and dithiotreitol (DTT)-induced aggregation. We observed the dependence between the number of positive charges on the surface of the PAMAM dendrimer and the values of zeta potential. Addition of dendrimers to insulin caused insignificant changes in the secondary structure. There was a small decrease in ellipticity, but it did not result in alterations in the circular dichroism (CD) spectrum shape. Dendrimers neither induced protein aggregation nor inhibited the aggregation process induced by DTT, except for 0.01 µmol/l concentration.

  5. Visual attentional load influences plasticity in the human motor cortex.

    Science.gov (United States)

    Kamke, Marc R; Hall, Michelle G; Lye, Hayley F; Sale, Martin V; Fenlon, Laura R; Carroll, Timothy J; Riek, Stephan; Mattingley, Jason B

    2012-05-16

    Neural plasticity plays a critical role in learning, memory, and recovery from injury to the nervous system. Although much is known about the physical and physiological determinants of plasticity, little is known about the influence of cognitive factors. In this study, we investigated whether selective attention plays a role in modifying changes in neural excitability reflecting long-term potentiation (LTP)-like plasticity. We induced LTP-like effects in the hand area of the human motor cortex using transcranial magnetic stimulation (TMS). During the induction of plasticity, participants engaged in a visual detection task with either low or high attentional demands. Changes in neural excitability were assessed by measuring motor-evoked potentials in a small hand muscle before and after the TMS procedures. In separate experiments plasticity was induced either by paired associative stimulation (PAS) or intermittent theta-burst stimulation (iTBS). Because these procedures induce different forms of LTP-like effects, they allowed us to investigate the generality of any attentional influence on plasticity. In both experiments reliable changes in motor cortex excitability were evident under low-load conditions, but this effect was eliminated under high-attentional load. In a third experiment we investigated whether the attentional task was associated with ongoing changes in the excitability of motor cortex, but found no difference in evoked potentials across the levels of attentional load. Our findings indicate that in addition to their role in modifying sensory processing, mechanisms of attention can also be a potent modulator of cortical plasticity.

  6. The Influence of Ouabain on Human Dendritic Cells Maturation

    Directory of Open Access Journals (Sweden)

    C. R. Nascimento

    2014-01-01

    Full Text Available Although known as a Na,K-ATPase inhibitor, several other cellular and systemic actions have been ascribed to the steroid Ouabain (Oua. Particularly in the immune system, our group showed that Ouabain acts on decreasing lymphocyte proliferation, synergizing with glucocorticoids in spontaneous thymocyte apoptosis, and also lessening CD14 expression and blocking CD16 upregulation on human monocytes. However, Ouabain effects on dendritic cells (DCs were not explored so far. Considering the peculiar plasticity and the importance of DCs in immune responses, the aim of our study was to investigate DC maturation under Ouabain influence. To generate immature DCs, human monocytes were cultured with IL-4 and GM-CSF (5 days. To investigate Ouabain role on DC activation, DCs were stimulated with TNF-α for 48 h in the presence or absence of Ouabain. TNF-induced CD83 expression and IL-12 production were abolished in DCs incubated with 100 nM Ouabain, though DC functional capacity concerning lymphocyte activation remained unaltered. Nevertheless, TNF-α-induced antigen capture downregulation, another maturation marker, occurred even in the presence of Ouabain. Besides, Ouabain increased HLA-DR and CD86 expression, whereas CD80 expression was maintained. Collectively, our results suggest that DCs respond to Ouabain maturating into a distinct category, possibly contributing to the balance between immunity and tolerance.

  7. Macro And Microcosmus: Moon Influence On The Human Body

    Science.gov (United States)

    Zanchin, Giorgio

    Belief in the action of the macrocosmus, i.e., celestial bodies, on the microcosmus, i.e., on man, goes back to the dawn of human thinking. More specifically, lunar phases have been considered to act on behaviour and on physiological functions. This possible relationship has not only been taken for granted for many centuries in ancient medicine but also investigated in a number of modern published works, mainly on the issues of emergency activity; violent behaviour; car accidents; drug overdose; menses and birth; and mood disorders. Indeed, if the idea that the stars and planets may influence human health and behaviour can be traced so far in the past, it seems that not only the laymen but a high proportion of health professionals continue to hold this credence: recently, in New Orleans a questionnaire sent to 325 people indicated that 140 individuals (43%) held the opinion that lunar phenomena alter personal behaviour. Specifically, it came out that mental health professionals (social workers, clinical psychologists, nurses' aides) held this belief more strongly than other occupational groups (Vance, 1995). A short historical outline of some old beliefs and the results of contemporary research on this fascinating, time-honoured field, will be presented.

  8. [Influence of genetic factors on human sexual orientation. Review].

    Science.gov (United States)

    Rodríguez-Larralde, Alvaro; Paradisi, Irene

    2009-09-01

    Human sexual orientation is a complex trait, influenced by several genes, experiential and sociocultural factors. These elements interact and produce a typical pattern of sexual orientation towards the opposite sex. Some exceptions exist, like bisexuality and homosexuality, which seem to be more frequent in males than females. Traditional methods for the genetic study of behavior multifactorial characteristics consist in detecting the presence of familial aggregation. In order to identify the importance of genetic and environmental factors in this aggregation, the concordance of the trait for monozygotic and dizygotic twins and for adopted sibs, reared together and apart, is compared. These types of studies have shown that familial aggregation is stronger for male than for female homosexuality. Based on the threshold method for multifactorial traits, and varying the frequency of homosexuality in the population between 4 and 10%, heritability estimates between 0.27 and 0.76 have been obtained. In 1993, linkage between homosexuality and chromosomal region Xq28 based on molecular approaches was reported. Nevertheless, this was not confirmed in later studies. Recently, a wide search of the genome has given significant or close to significant linkage values with regions 7q36, 8p12 and 10q26, which need to be studied more closely. Deviation in the proportion of X chromosome inactivation in mothers of homosexuals seems to favor the presence of genes related with sexual orientation in this chromosome. There is still much to be known about the genetics of human homosexuality.

  9. Uncorrelated Phase Noise Analysis for Millimeter-Wave Radiometer Imager Frequency Synthesizer

    Directory of Open Access Journals (Sweden)

    Jin Zhang

    2013-09-01

    Full Text Available In this paper, a nontrivial uncorrelated phase noise analysis is proposed for frequency synthesizer of a passive millimeter-wave Synthetic Aperture Interferometric Radiometer (SAIR imager named BHU-2D-U designed for concealed weapon detections on human bodies with high imaging rates. This synthesizer provides local oscillators both for millimeter-wave front-ends and intermediate frequency IQ demodulators for the receivers. The influence of synthesizer uncorrelated phase noise in different offset frequency ranges on the visibility phase errors have been systematically investigated with phase noise mismatch requirements drawn. Integrated RMS phase error has been applied to establish uncorrelated phase noise requirements for visibility error control. Measurement results have proved that uncorrelated phase noise does exist among synthesizer output pairs, and the previously defined requirements are achieved with imaging results proposed. In conclusion, the uncorrelated phase noise effects on SAIR visibility errors have been concretized to phase noise design requirements, which have been realized by synthesizer design.

  10. THE INFLUENCE OF INFORMATION TECHNOLOGIES ON THE HUMAN FACTOR WITHIN AN ORGNANIZATION

    OpenAIRE

    Sarkiunaite, Ingrida

    2005-01-01

    The article discusses a number of important changes of influence of information technologies on human factor within the organization. The focus of the article is on human factor and IT using problem. According to the theoretical and empirical material of IT influence on human factor, aspects of information technology are analyzed.

  11. Impact of Vessel Noise on Oyster Toadfish (Opsanus tau) Behavior and Implications for Underwater Noise Management

    Science.gov (United States)

    Krahforst, Cecilia S.

    Underwater noise and its impacts on marine life are growing management concerns. This dissertation considers both the ecological and social concerns of underwater noise, using the oyster toadfish (Opsanus tau) as a model species. Oyster toadfish call for mates using a boatwhistle sound, but increased ambient noise levels from vessels or other anthropogenic activities are likely to influence the ability of males to find mates. If increased ambient noise levels reduce fish fitness then underwater noise can impact socially valued ecosystem services (e.g. fisheries). The following ecological objectives of the impacts of underwater noise on oyster toadfish were investigated: (1) to determine how noise influences male calling behavior; (2) to assess how areas of high vessel activity ("noisy") and low vessel activity ("quiet") influence habitat utilization (fish standard length and occupancy rate); and (3) to discover if fitness (number of clutches and number of embryos per clutch) is lower in "noisy" compared with "quiet" sites. Field experiments were executed in "noisy" and "quiet" areas. Recorded calls by males in response to playback sounds (vessel, predator, and snapping shrimp sounds) and egg deposition by females ("noisy" vs. "quiet" sites) demonstrated that oyster toadfish are impacted by underwater noise. First, males decreased their call rates and called louder in response to increased ambient noise levels. Second, oyster toadfish selected nesting sites in areas with little or no inboard motorboat activity. Third, male oyster toadfish at "noisy" sites either had no egg clutches on their shelters or the number of embryos per clutch was significantly lower than in the "quiet" areas. Underwater noise and disturbance from vessels are influencing the fitness of the oyster toadfish. The social significance of the growing concerns regarding underwater noise was investigated by identifying dominant themes found within two types of texts: four recent underwater noise

  12. Psychoacoustic study on contribution of fan noise to engine noise

    Science.gov (United States)

    Zhang, Junhong; Liu, Hai; Bi, Fengrong; Ni, Guangjian; Zhang, Guichang; Lin, Jiewei; Yu, Hanzhengnan

    2012-07-01

    There are more researches on engine fan noise control focusing on reducing fan noise level through optimizing fan structure, and a lot of research achievements have been obtained. However, researches on the effect of fan noise to engine noise quality are lacking. The influences of the effects of fan structure optimization on the engine noise quality are unclear. Thus, there will be a decline in fan noise level, but the deterioration of engine noise quality. Aiming at the above problems, in consideration of fan structure design and engine noise quality, an innovative method to analyze the contribution of fan noise to engine noise quality using psychoacoustic theory is proposed. The noises of diesel engine installing different cooling fans are measured by using the acoustic pressure method. The experiment results are regarded as analysis samples. The model of sensory pleasantness is used to analyze the sound quality of a diesel engine with different cooling fans. Results show that after installing 10-blade fan in medium diameter the sensory pleasantness at each test point is increased, and the increase is 13.53% on average, which indicate the improvement of the engine noise quality. In order to verify the psychoacoustical analysis, the subjective assessment is carried out. The test result shows the noise quality of engine installed 10-blade fan in medium diameter is most superior. 1/3 octave frequency spectrum analysis is used to study the reason of the improvement of engine noise quality. It is found that after installing proper cooling fan the sound pressure level below 400 Hz are obviously increased, the frequency assignment and spectral envelope are more reasonable and a proper cooling fan can optimize the spectrum structure of the engine noise. The psychoacoustic study is applied in the contribution of fan noise to engine noise, and the idea of engine sound quality improvement through the structure optimization is proposed.

  13. Modeling of noise pollution and estimated human exposure around İstanbul Atatürk Airport in Turkey.

    Science.gov (United States)

    Ozkurt, Nesimi; Sari, Deniz; Akdag, Ali; Kutukoglu, Murat; Gurarslan, Aliye

    2014-06-01

    The level of aircraft noise exposure around İstanbul Atatürk Airport was calculated according to the European Noise Directive. These calculations were based on the actual flight data for each flight in the year 2011. The study area was selected to cover of 25km radius centered on the Aerodrome Reference Point of the airport. The geographical data around İstanbul Atatürk Airport was used to prepare elevation, residential building, auxiliary building, hospital and school layers in SoundPlan software. It was found that 1.2% of the land area of İstanbul City exceeds the threshold of 55dB(A) during daytime. However, when the exceedance of threshold of 65dB(A)is investigated, the affected area is found quite small (0.2% of land area of city). About 0.3% of the land area of İstanbul City has noise levels exceeding 55dB(A) during night-time. Our results show that about 4% of the resident population was exposed to 55dB(A) or higher noises during daytime in İstanbul. When applying the second threshhold criteria, nearly 1% of the population is exposed to noise levels greater than 65dB(A). At night-time, 1.3% of the population is exposed to 55dB(A) or higher noise levels.

  14. Influence of Fragrances on Human Psychophysiological Activity: With Special Reference to Human Electroencephalographic Response

    Directory of Open Access Journals (Sweden)

    Kandhasamy Sowndhararajan

    2016-11-01

    Full Text Available The influence of fragrances such as perfumes and room fresheners on the psychophysiological activities of humans has been known for a long time, and its significance is gradually increasing in the medicinal and cosmetic industries. A fragrance consists of volatile chemicals with a molecular weight of less than 300 Da that humans perceive through the olfactory system. In humans, about 300 active olfactory receptor genes are devoted to detecting thousands of different fragrance molecules through a large family of olfactory receptors of a diverse protein sequence. The sense of smell plays an important role in the physiological effects of mood, stress, and working capacity. Electrophysiological studies have revealed that various fragrances affected spontaneous brain activities and cognitive functions, which are measured by an electroencephalograph (EEG. The EEG is a good temporal measure of responses in the central nervous system and it provides information about the physiological state of the brain both in health and disease. The EEG power spectrum is classified into different frequency bands such as delta (0.5–4 Hz, theta (4–8 Hz, alpha (8–13 Hz, beta (13–30 Hz and gamma (30–50 Hz, and each band is correlated with different features of brain states. A quantitative EEG uses computer software to provide the topographic mapping of the brain activity in frontal, temporal, parietal and occipital brain regions. It is well known that decreases of alpha and beta activities and increases of delta and theta activities are associated with brain pathology and general cognitive decline. In the last few decades, many scientific studies were conducted to investigate the effect of inhalation of aroma on human brain functions. The studies have suggested a significant role for olfactory stimulation in the alteration of cognition, mood, and social behavior. This review aims to evaluate the available literature regarding the influence of fragrances on the

  15. Influence of base and PAG on deprotection blur in EUV photoresists and some thoughts on shot noise

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Juanita; Anderson, Christopher; Naulleau, Patrick; Niakoula, Demitra; Hassanein, Elsayed; Brainard, Robert; Gallatin, Gregg; Dean, Kim

    2008-06-01

    A contact-hole deprotection blur metric has been used to monitor the deprotection blur of an experimental open platform resist (EH27) as the weight percent of base and photo acid generator (PAG) were varied. Patterning ability in 1:1 line-space patterns is shown to improve at smaller pitches as base/PAG are increased however no significant change in deprotection blur was observed. Isolated (or intrinsic) line-edge-roughness (LER) is shown to improve with increased base loading while remaining fixed through PAG loading. A discussion of improved patterning performance as related to shot noise and deprotection blur concludes with a speculation that the spatial distribution of PAG molecules has been playing some role, perhaps a dominant one, in determining the uniformity of photo generated acids in the resists that have been studied.

  16. Influence of inductance induced noise in an YBa2Cu3O7 dc-SQUID at high operation temperatures

    DEFF Research Database (Denmark)

    Nilsson, P. Å.; Claeson, T.; Hansen, J. B.;

    1994-01-01

    The voltage modulation depth of a high T(c) dc-SQUID was measured at temperatures close to T(c) and compared to a model by Enpuku et al. where the flux noise from the SQUID inductance is taken into account. The device was an YBa2Cu3O7 dc-SQUID made on a bicrystal substrate of SrTiO3. The design...... was of the Ketchen square-washer type with an inductance of 67 pH. Measurements were made in a temperature interval from 75 to 87 K, where the voltage modulation depth changed from 4.5 to 1.4 muV in close agreement with the model....

  17. Prediction of the dynamic oscillation threshold in a clarinet model with a linearly increasing blowing pressure : Influence of noise

    CERN Document Server

    Bergeot, Baptiste; Vergez, Christophe; Gazengel, Bruno

    2013-01-01

    This paper presents an analysis of the effects of noise and precision on a simplified model of the clarinet driven by a variable control parameter. In a previous work [5], the dynamic oscillation threshold of a simplified model of a clarinet is obtained analytically. In the present article, the sensitivity of the dynamic threshold on precision is analyzed as a stochastic variable introduced in the model. A new theoretical expression is given for the dynamic thresholds in presence of the stochastic variable, providing a fair prediction of the thresholds found in finite-precision simulations. The dynamic thresholds are found to depend on increase rate and are independent on the initial value of the parameter, both in simulations and in theory.

  18. Frequently updated noise threat maps created with use of supercomputing grid

    Directory of Open Access Journals (Sweden)

    Szczodrak Maciej

    2014-09-01

    Full Text Available An innovative supercomputing grid services devoted to noise threat evaluation were presented. The services described in this paper concern two issues, first is related to the noise mapping, while the second one focuses on assessment of the noise dose and its influence on the human hearing system. The discussed serviceswere developed within the PL-Grid Plus Infrastructure which accumulates Polish academic supercomputer centers. Selected experimental results achieved by the usage of the services proposed were presented. The assessment of the environmental noise threats includes creation of the noise maps using either ofline or online data, acquired through a grid of the monitoring stations. A concept of estimation of the source model parameters based on the measured sound level for the purpose of creating frequently updated noise maps was presented. Connecting the noise mapping grid service with a distributed sensor network enables to automatically update noise maps for a specified time period. Moreover, a unique attribute of the developed software is the estimation of the auditory effects evoked by the exposure to noise. The estimation method uses a modified psychoacoustic model of hearing and is based on the calculated noise level values and on the given exposure period. Potential use scenarios of the grid services for research or educational purpose were introduced. Presentation of the results of predicted hearing threshold shift caused by exposure to excessive noise can raise the public awareness of the noise threats.

  19. Influence of Magnesium Alloy Degradation on Undifferentiated Human Cells.

    Directory of Open Access Journals (Sweden)

    Francesca Cecchinato

    Full Text Available Magnesium alloys are of particular interest in medical science since they provide compatible mechanical properties with those of the cortical bone and, depending on the alloying elements, they have the capability to tailor the degradation rate in physiological conditions, providing alternative bioresorbable materials for bone applications. The present study investigates the in vitro short-term response of human undifferentiated cells on three magnesium alloys and high-purity magnesium (Mg.The degradation parameters of magnesium-silver (Mg2Ag, magnesium-gadolinium (Mg10Gd and magnesium-rare-earth (Mg4Y3RE alloys were analysed after 1, 2, and 3 days of incubation in cell culture medium under cell culture condition. Changes in cell viability and cell adhesion were evaluated by culturing human umbilical cord perivascular cells on corroded Mg materials to examine how the degradation influences the cellular development.The pH and osmolality of the medium increased with increasing degradation rate and it was found to be most pronounced for Mg4Y3RE alloy. The biological observations showed that HUCPV exhibited a more homogeneous cell growth on Mg alloys compared to high-purity Mg, where they showed a clustered morphology. Moreover, cells exhibited a slightly higher density on Mg2Ag and Mg10Gd in comparison to Mg4Y3RE, due to the lower alkalinisation and osmolality of the incubation medium. However, cells grown on Mg10Gd and Mg4Y3RE generated more developed and healthy cellular structures that allowed them to better adhere to the surface. This can be attributable to a more stable and homogeneous degradation of the outer surface with respect to the incubation time.

  20. Relationship of firing intervals of human motor units to the trajectory of post-spike after-hyperpolarization and synaptic noise.

    Science.gov (United States)

    Matthews, P B

    1996-04-15

    1. Interspike interval distributions from human motor units of a variety of muscles were analysed to assess the role of synaptic noise in excitation. The time course of the underlying post-spike after-hyperpolarization (AHP) was deduced by applying a specially developed transform to the interval data. Different firing rates were studied both by varying the firing voluntarily, and by selecting subpopulations of spikes for a given firing rate from long recordings with slight variations in frequency. 2. At low firing rates the interval histograms had an exponential tail. Thus at long intervals, the motoneurone was randomly excited by noise and its post-spike AHP was complete. This contrasts with the firing produced by intracellular current injection in the cat, when the membrane potential increases linearly until threshold is reached. The interval histogram was therefore analysed with the aid of a model of synaptic excitation to deduce the mean 'trajectory' of membrane voltage in the last part of the interspike interval. 3. The computer model, described in the Appendix, was used to determine the effect of the mean level of membrane potential on the probability of a spike being excited, per unit time, during an on-going interspike interval. All variables were treated as voltages, with synaptic noise simulated by time-smoothed Gaussian noise. This enabled an interval distribution to be transformed into a segment of the underlying trajectory of the membrane potential; the potential was expressed in terms of the noise amplitude and the spike threshold. 4. At low firing rates, the equilibrium value of the membrane voltage trajectory lay well below threshold; the deviation typically corresponded to the standard deviation of the noise or more. The noise standard deviation was estimated to be about 2 mV. 5. With increasing mean firing rate, the near-threshold portion of the trajectory obtainable from the histogram occurred earlier, was steeper and rose to a higher level

  1. Holes influence the mutation spectrum of human mitochondrial DNA

    Science.gov (United States)

    Villagran, Martha; Miller, John

    Mutations drive evolution and disease, showing highly non-random patterns of variant frequency vs. nucleotide position. We use computational DNA hole spectroscopy [M.Y. Suarez-Villagran & J.H. Miller, Sci. Rep. 5, 13571 (2015)] to reveal sites of enhanced hole probability in selected regions of human mitochondrial DNA. A hole is a mobile site of positive charge created when an electron is removed, for example by radiation or contact with a mutagenic agent. The hole spectra are quantum mechanically computed using a two-stranded tight binding model of DNA. We observe significant correlation between spectra of hole probabilities and of genetic variation frequencies from the MITOMAP database. These results suggest that hole-enhanced mutation mechanisms exert a substantial, perhaps dominant, influence on mutation patterns in DNA. One example is where a trapped hole induces a hydrogen bond shift, known as tautomerization, which then triggers a base-pair mismatch during replication. Our results deepen overall understanding of sequence specific mutation rates, encompassing both hotspots and cold spots, which drive molecular evolution.

  2. Influence of cigarette smoking on human autonomic function

    Science.gov (United States)

    Niedermaier, O. N.; Smith, M. L.; Beightol, L. A.; Zukowska-Grojec, Z.; Goldstein, D. S.; Eckberg, D. L.

    1993-01-01

    BACKGROUND. Although cigarette smoking is known to lead to widespread augmentation of sympathetic nervous system activity, little is known about the effects of smoking on directly measured human sympathetic activity and its reflex control. METHODS AND RESULTS. We studied the acute effects of smoking two research-grade cigarettes on muscle sympathetic nerve activity and on arterial baroreflex-mediated changes of sympathetic and vagal neural cardiovascular outflows in eight healthy habitual smokers. Measurements were made during frequency-controlled breathing, graded Valsalva maneuvers, and carotid baroreceptor stimulation with ramped sequences of neck pressure and suction. Smoking provoked the following changes: Arterial pressure increased significantly, and RR intervals, RR interval spectral power at the respiratory frequency, and muscle sympathetic nerve activity decreased. Plasma nicotine levels increased significantly, but plasma epinephrine, norepinephrine, and neuropeptide Y levels did not change. Peak sympathetic nerve activity during and systolic pressure overshoots after Valsalva straining increased significantly in proportion to increases of plasma nicotine levels. The average carotid baroreceptor-cardiac reflex relation shifted rightward and downward on arterial pressure and RR interval axes; average gain, operational point, and response range did not change. CONCLUSIONS. In habitual smokers, smoking acutely reduces baseline levels of vagal-cardiac nerve activity and completely resets vagally mediated arterial baroreceptor-cardiac reflex responses. Smoking also reduces muscle sympathetic nerve activity but augments increases of sympathetic activity triggered by brief arterial pressure reductions. This pattern of autonomic changes is likely to influence smokers' responses to acute arterial pressure reductions importantly.

  3. Environmental influences on human migration in rural Ecuador.

    Science.gov (United States)

    Gray, Clark; Bilsborrow, Richard

    2013-08-01

    The question of whether environmental conditions influence human migration has recently gained considerable attention, driven by claims that global environmental change will displace large populations. Despite this high level of interest, few quantitative studies have investigated the potential effects of environmental factors on migration, particularly in the developing world and for gradual but pervasive forms of environmental change. To address this, a retrospective migration survey was conducted in rural Ecuador and linked to data on topography, climate, and weather shocks. These data were used to estimate multivariate event history models of alternative forms of mobility (local mobility, internal migration, and international migration), controlling for a large number of covariates. This approach is generalizable to other study areas and responds to calls for the development of more rigorous methods in this field. The results indicate that adverse environmental conditions do not consistently increase rural out-migration and, in some cases, reduce migration. Instead, households respond to environmental factors in diverse ways, resulting in complex migratory responses. Overall, the results support an alternative narrative of environmentally induced migration that recognizes the adaptability of rural households in responding to environmental change.

  4. Influence of human genetic variation on nutritional requirements.

    Science.gov (United States)

    Stover, Patrick J

    2006-02-01

    Genetic variation is known to affect food tolerances among human subpopulations and may also influence dietary requirements, giving rise to the new field of nutritional genomics and raising the possibility of individualizing nutritional intake for optimal health and disease prevention on the basis of an individual's genome. However, because gene-diet interactions are complex and poorly understood, the use of genomic knowledge to adjust population-based dietary recommendations is not without risk. Whereas current recommendations target most of the population to prevent nutritional deficiencies, inclusion of genomic criteria may indicate subpopulations that may incur differential benefit or risk from generalized recommendations and fortification policies. Current efforts to identify gene alleles that affect nutrient utilization have been enhanced by the identification of genetic variations that have expanded as a consequence of selection under extreme conditions. Identification of genetic variation that arose as a consequence of diet as a selective pressure helps to identify gene alleles that affect nutrient utilization. Understanding the molecular mechanisms underlying gene-nutrient interactions and their modification by genetic variation is expected to result in dietary recommendations and nutritional interventions that optimize individual health.

  5. Adaptation to fragmentation: evolutionary dynamics driven by human influences.

    Science.gov (United States)

    Cheptou, Pierre-Olivier; Hargreaves, Anna L; Bonte, Dries; Jacquemyn, Hans

    2017-01-19

    Fragmentation-the process by which habitats are transformed into smaller patches isolated from each other-has been identified as a major threat for biodiversity. Fragmentation has well-established demographic and population genetic consequences, eroding genetic diversity and hindering gene flow among patches. However, fragmentation should also select on life history, both predictably through increased isolation, demographic stochasticity and edge effects, and more idiosyncratically via altered biotic interactions. While species have adapted to natural fragmentation, adaptation to anthropogenic fragmentation has received little attention. In this review, we address how and whether organisms might adapt to anthropogenic fragmentation. Drawing on selected case studies and evolutionary ecology models, we show that anthropogenic fragmentation can generate selection on traits at both the patch and landscape scale, and affect the adaptive potential of populations. We suggest that dispersal traits are likely to experience especially strong selection, as dispersal both enables migration among patches and increases the risk of landing in the inhospitable matrix surrounding them. We highlight that suites of associated traits are likely to evolve together. Importantly, we show that adaptation will not necessarily rescue populations from the negative effects of fragmentation, and may even exacerbate them, endangering the entire metapopulation.This article is part of the themed issue 'Human influences on evolution, and the ecological and societal consequences'. © 2016 The Author(s).

  6. The Adverse Effects of Heavy Metals with and without Noise Exposure on the Human Peripheral and Central Auditory System: A Literature Review

    Directory of Open Access Journals (Sweden)

    Marie-Josée Castellanos

    2016-12-01

    Full Text Available Exposure to some chemicals in the workplace can lead to occupational chemical-induced hearing loss. Attention has mainly focused on the adverse auditory effects of solvents. However, other chemicals such as heavy metals have been also identified as ototoxic agents. The aim of this work was to review the current scientific knowledge about the adverse auditory effects of heavy metal exposure with and without co-exposure to noise in humans. PubMed and Medline were accessed to find suitable articles. A total of 49 articles met the inclusion criteria. Results from the review showed that no evidence about the ototoxic effects in humans of manganese is available. Contradictory results have been found for arsenic, lead and mercury as well as for the possible interaction between heavy metals and noise. All studies found in this review have found that exposure to cadmium and mixtures of heavy metals induce auditory dysfunction. Most of the studies investigating the adverse auditory effects of heavy metals in humans have investigated human populations exposed to lead. Some of these studies suggest peripheral and central auditory dysfunction induced by lead exposure. It is concluded that further evidence from human studies about the adverse auditory effects of heavy metal exposure is still required. Despite this issue, audiologists and other hearing health care professionals should be aware of the possible auditory effects of heavy metals.

  7. The Adverse Effects of Heavy Metals with and without Noise Exposure on the Human Peripheral and Central Auditory System: A Literature Review.

    Science.gov (United States)

    Castellanos, Marie-Josée; Fuente, Adrian

    2016-12-09

    Exposure to some chemicals in the workplace can lead to occupational chemical-induced hearing loss. Attention has mainly focused on the adverse auditory effects of solvents. However, other chemicals such as heavy metals have been also identified as ototoxic agents. The aim of this work was to review the current scientific knowledge about the adverse auditory effects of heavy metal exposure with and without co-exposure to noise in humans. PubMed and Medline were accessed to find suitable articles. A total of 49 articles met the inclusion criteria. Results from the review showed that no evidence about the ototoxic effects in humans of manganese is available. Contradictory results have been found for arsenic, lead and mercury as well as for the possible interaction between heavy metals and noise. All studies found in this review have found that exposure to cadmium and mixtures of heavy metals induce auditory dysfunction. Most of the studies investigating the adverse auditory effects of heavy metals in humans have investigated human populations exposed to lead. Some of these studies suggest peripheral and central auditory dysfunction induced by lead exposure. It is concluded that further evidence from human studies about the adverse auditory effects of heavy metal exposure is still required. Despite this issue, audiologists and other hearing health care professionals should be aware of the possible auditory effects of heavy metals.

  8. Non-auditory Effect of Noise Pollution and Its Risk on Human Brain Activity in Different Audio Frequency Using Electroencephalogram Complexity.

    Science.gov (United States)

    Allahverdy, Armin; Jafari, Amir Homayoun

    2016-10-01

    Noise pollution is one of the most harmful ambiance disturbances. It may cause many deficits in ability and activity of persons in the urban and industrial areas. It also may cause many kinds of psychopathies. Therefore, it is very important to measure the risk of this pollution in different area. This study was conducted in the Department of Medical Physics and Biomedical Engineering, Tehran University of Medical Sciences from June to September of 2015, in which, different frequencies of noise pollution were played for volunteers. 16-channel EEG signal was recorded synchronously, then by using fractal dimension and relative power of Beta sub-band of EEG, the complexity of EEG signals was measured. As the results, it is observed that the average complexity of brain activity is increased in the middle of audio frequency range and the complexity map of brain activity changes in different frequencies, which can show the effects of frequency changes on human brain activity. The complexity of EEG is a good measure for ranking the annoyance and non-auditory risk of noise pollution on human brain activity.

  9. Natural and man-made terrestrial electromagnetic noise: an outlook

    Directory of Open Access Journals (Sweden)

    A. Meloni

    2007-06-01

    Full Text Available The terrestrial environment is continuously exposed to electromagnetic radiations which set up a «background» electromagnetic noise. Within the Non Ionizing Radiation band (NIR, i.e. for frequencies lower than 300 GHz, this background can have a natural or an artificial origin. Natural origins of electromagnetic radiations are generally atmospheric or cosmic while artificial origins are technological applications, power transmission, communications, etc. This paper briefly describes the natural and man-made electromagnetic noise in the NIR band. Natural noise comes from a large variety of sources involving different physical phenomena and covering a wide range of frequencies and showing various propagation characteristics with an extremely broad range of power levels. Due to technological growth man-made electromagnetic noise is nowadays superimposed on natural noise almost everywhere on Earth. In the last decades man-made noise has increased dramatically over and above the natural noise in residential and business areas. This increase has led some scientists to consider possible negative effects of electromagnetic waves on human life and living systems in general. Accurate measurements of natural and man-made electromagnetic noise are necessary to understand the relative power levels in the different bands and their influence on life.

  10. Influence of base and PAG on deprotection blur in EUV photoresists and some thoughts on shot noise

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Christopher N.; Naulleau, Patrick P.; Niakoula, Dimitra; Hassanein, Elsayed; Brainard, Robert; Gallatin, Gregg; Dean, Kim

    2008-06-01

    A contact-hole deprotection blur metric has been used to monitor the deprotection blur of an experimental open platform resist (EH27) as the weight percent of base and photo acid generator (PAG) were varied. A 6x increase in base weight percent is shown to reduce the size of successfully patterned 1:1 line-space features from 52 nm to 39 nm without changing deprotection blur. Corresponding isolated line-edge-roughness is reduced from 6.9 nm to 4.1 nm. A 2x increase in PAG weight percent is shown to improve 1:1 line-space patterning from 47 nm to 40 nm without changing deprotection blur or isolated LER. A discussion of improved patterning performance as related to shot noise and deprotection blur concludes with a speculation that the spatial distribution of PAG molecules has been playing some role, perhaps a dominant one, in determining the uniformity of photo generated acids in the resists that have been studied.

  11. Numerical exploration of the influence of neural noise on the psychometric function at low stimulation intensity levels

    Indian Academy of Sciences (India)

    C M Gómez

    2008-12-01

    The relationship between stimulus intensity and the probability of detecting the presence of the stimulus is described by the psychometrical function. The probabilistic nature of this relationship is based on the stochastic behaviour of sensory neural channels and sensory networks involved in perceptual processing (Kiang 1968). This study tries to establish a continuum of variability across different levels of integration in the central nervous system. Once the opening and closing times of ionic channels was simulated, a threshold to the collective behaviour of voltage-gated ionic channels was imposed in order to generate the spike train of a single neuron. Afterwards, the trains of spikes of different neurons were added up, simulating the activity of a sensory nerve. By adding the activity due to the stimulus to the spontaneous neural behaviour, the psychometric function was simulated using a thresholding approach. The results can replicate the stochastic resonance phenomenon, but also open up the possibility that attentional phenomena can be mediated not only by increasing neural activity (bursting or oscillatory), but also by increasing noise at the neural level.

  12. Numerical Research about Influence of Blade Outlet Angle on Flow-Induced Noise and Vibration for Centrifugal Pump

    Directory of Open Access Journals (Sweden)

    Ailing Yang

    2014-03-01

    Full Text Available A hybrid numerical method was used to calculate the flow-induced noise and vibration of the centrifugal pump in the paper. The unsteady flows inside the centrifugal pumps with different blade outlet angles were simulated firstly. The unsteady pressure on the inner surface of the volute and the unsteady force applied on the impeller were analyzed. Then the vibration of the volute and sound field were calculated based on an acoustic-vibro-coupling method. The results show that the pump head has increased 7% while the hydraulic efficiency decreased 11.75% as blade outlet angles increased from 18° to 39°. The amplitude of pressure fluctuation at the first blade passing frequency has decreased but increased at the second-order blade passing frequency as the angle growing. The total fluctuation power near volute tongue goes up about 12% every 3° increment of blade outlet angle. The results also show that vibrating-velocity of the volute at second-order blade passing frequency is much higher than at other frequencies, and the velocity increases rapidly as blade outlet angle varies from 18° to 39°. At the same time, the sound pressure level outside the pump has increased about 8.6 dB when the angle increased from 18° to 39°.

  13. Monitoring of Noise During Ganeshotsav

    Directory of Open Access Journals (Sweden)

    Mrs. P. Saler

    2011-09-01

    Full Text Available Sound is a form of energy emitted by a vibrating body causing change in pressure of the surrounding elastic medium through which energy is transmitted. Noise has been defined as unwanted sound. Noise is a disturbance to the human environment which is escalating at a high rate. There are numerous effects of noise on human and environment due to the increase in noise pollution slowly, insensibly; we seem to accept noise and the physiological and psychological deterioration that accompanies it as an inevitable part of our lives. Althoughattempts have been made to regulate noise pollution by setting standards for some of the major sources of noise, we often are unable to monitor them. One such source of noise in India is celebration of festival and especially in Maharashtra, the biggest festival- Ganeshostav. The way noise levels are increasing year by year during this festival, it seems we enjoy these sounds, though it has harmful effects on Human Health and Environment. This paper focuses on study of noise pollution during Ganesh Festival and also its other causes and effects.

  14. Catastrophic debris-flows: geological hazard and human influence

    Science.gov (United States)

    Del Ventisette, Chiara; Garfagnoli, Francesca; Ciampalini, Andrea; Battistini, Alessandro; Gigli, Giovanni; Moretti, Sandro; Casagli, Nicola

    2013-04-01

    Rainfall-induced landslides are widespread phenomena often affecting urbanized areas and causing intense damages and casualties. The management of the post-event phase requires a fast evaluation of the involved areas and triggering factors. The latter are fundamental to evaluate the stability of the area affected by landslides, in order to facilitate quick and safe activities of the Civil Protection Authorities during the emergency. On October 1st 2009, a prolonged and intense rainstorm triggered hundreds of landslides (predominantly debris flows) in an area of about 50 km2 in the north-eastern sector of Sicily (Italy). Debris flows swept the highest parts of many villages and passed over the SS114 state highway and the Messina-Catania railway, causing more than 30 fatalities. This work deals with the geological and hydro-geomorphological studies performed as a part of the post-disaster activities operated in collaboration with Civil Protection Authority, with the aim of examining landslides effects and mechanisms. The data were elaborated into a GIS platform, to evaluate the influence of urbanization on the drainage pattern and were correlated with the lithological and structural framework of the area. The case study of Giampilieri focuses the attention on the necessity of sustainable land use and reasonable urban management in areas characterized by a high hydrogeological hazard and on the tremendous destructive power of these phenomena, which are capable of causing a large number of victims in such small villages. Field surveys and stereo-photo geomorphological analysis revealed a significant human influence on determining landslide triggering causes, as well as the final amount of damage. In particular, destruction and injuries in the built-up area of Giampilieri were made even more severe by the main water flow lines made narrower due to building activity and enlargement of the urban area. The area maintains a high degree of hazard: deposits of poorly

  15. Human REM sleep: influence on feeding behaviour, with clinical implications.

    Science.gov (United States)

    Horne, James A

    2015-08-01

    Rapid eye movement (REM) sleep shares many underlying mechanisms with wakefulness, to a much greater extent than does non-REM, especially those relating to feeding behaviours, appetite, curiosity, exploratory (locomotor) activities, as well as aspects of emotions, particularly 'fear extinction'. REM is most evident in infancy, thereafter declining in what seems to be a dispensable manner that largely reciprocates increasing wakefulness. However, human adults retain more REM than do other mammals, where for us it is most abundant during our usual final REM period (fREMP) of the night, nearing wakefulness. The case is made that our REM is unusual, and that (i) fREMP retains this 'dispensability', acting as a proxy for wakefulness, able to be forfeited (without REM rebound) and substituted by physical activity (locomotion) when pressures of wakefulness increase; (ii) REM's atonia (inhibited motor output) may be a proxy for this locomotion; (iii) our nocturnal sleep typically develops into a physiological fast, especially during fREMP, which is also an appetite suppressant; (iv) REM may have 'anti-obesity' properties, and that the loss of fREMP may well enhance appetite and contribute to weight gain ('overeating') in habitually short sleepers; (v) as we also select foods for their hedonic (emotional) values, REM may be integral to developing food preferences and dislikes; and (vii) REM seems to have wider influences in regulating energy balance in terms of exercise 'substitution' and energy (body heat) retention. Avenues for further research are proposed, linking REM with feeding behaviours, including eating disorders, and effects of REM-suppressant medications.

  16. Beat Noise Limitation in Coherent Time-Spreading OCDMA Network

    Institute of Scientific and Technical Information of China (English)

    Ken-ichi; Kitayama; Koji; Mutsushima

    2003-01-01

    The BER performance of the coherent time-spreading OCDMA network is analyzed by considering the MAI and beat noises as well as the other additive noises. The influence and solution for the beat noise issue are discussed.

  17. Investigation of the influence of air gap thickness and eccentricity on the noise of the rotating electrical machine

    Directory of Open Access Journals (Sweden)

    Donát M.

    2013-12-01

    Full Text Available This article deals with the numerical modelling of the dynamic response of the rotating electrical machine on the application of the magnetic forces. The special attention is paid to the modelling of the magnetic forces that act on the stator winding of the machine and the computational model of the modal properties of the stator winding. The created computational model was used to investigation of the influence of the nominal air gap thickness and the air gap eccentricity on the sound power radiated by outer surface of the stator of the machine. The obtained results show that the nominal air gap thickness has slightly greater influence on the sound power of the machine than eccentricity of the air gap.

  18. Sound over Matter: The Effects of Functional Noise, Robot Size and Approach Velocity in Human-Robot Encounters

    NARCIS (Netherlands)

    Joosse, M.P.; Lohse, M.; Evers, Vanessa

    2014-01-01

    In our previous work we introduced functional noise as a modality for robots to communicate intent [6]. In this follow-up experiment, we replicated the first study with a robot which was taller in order to find out if the same results would apply to a tall vs. a short robot. Our results show a

  19. Sound over Matter: The Effects of Functional Noise, Robot Size and Approach Velocity in Human-Robot Encounters

    NARCIS (Netherlands)

    Joosse, M.P.; Lohse, M.; Evers, Vanessa

    2014-01-01

    In our previous work we introduced functional noise as a modality for robots to communicate intent [6]. In this follow-up experiment, we replicated the first study with a robot which was taller in order to find out if the same results would apply to a tall vs. a short robot. Our results show a simil

  20. Influence Of Globalization On Human Resource Development In ...

    African Journals Online (AJOL)

    It was seen as a panacea for the training of marketable, self employed individuals ... presence in human resource development, international transfer of technology. ... human resource planning based on the cost benefit analysis of education.

  1. Balancing Human and Inter-Agent Influences for Shared Control of Bio-Inspired Collectives

    Science.gov (United States)

    2014-10-01

    multiple uavs ,” IEEE Robotics and Automation Magazine, 2009. [4] Z. Kira and M. A. Potter, “Exerting human control over decentral- ized robot swarms ,” in...how influence is shared between the human and the swarm and (2) the resulting success of the human- swarm interaction. Note that related literature...control is shared: persistence and span. We define per- sistence as how long the human signals the swarm and span as how many agents the human

  2. Speech recognition in natural background noise.

    Directory of Open Access Journals (Sweden)

    Julien Meyer

    Full Text Available In the real world, human speech recognition nearly always involves listening in background noise. The impact of such noise on speech signals and on intelligibility performance increases with the separation of the listener from the speaker. The present behavioral experiment provides an overview of the effects of such acoustic disturbances on speech perception in conditions approaching ecologically valid contexts. We analysed the intelligibility loss in spoken word lists with increasing listener-to-speaker distance in a typical low-level natural background noise. The noise was combined with the simple spherical amplitude attenuation due to distance, basically changing the signal-to-noise ratio (SNR. Therefore, our study draws attention to some of the most basic environmental constraints that have pervaded spoken communication throughout human history. We evaluated the ability of native French participants to recognize French monosyllabic words (spoken at 65.3 dB(A, reference at 1 meter at distances between 11 to 33 meters, which corresponded to the SNRs most revealing of the progressive effect of the selected natural noise (-8.8 dB to -18.4 dB. Our results showed that in such conditions, identity of vowels is mostly preserved, with the striking peculiarity of the absence of confusion in vowels. The results also confirmed the functional role of consonants during lexical identification. The extensive analysis of recognition scores, confusion patterns and associated acoustic cues revealed that sonorant, sibilant and burst properties were the most important parameters influencing phoneme recognition. . Altogether these analyses allowed us to extract a resistance scale from consonant recognition scores. We also identified specific perceptual consonant confusion groups depending of the place in the words (onset vs. coda. Finally our data suggested that listeners may access some acoustic cues of the CV transition, opening interesting perspectives for

  3. 声学建模和阻尼损失系数对舱室噪声影响的研究%Study on the Influence of the Acoustic Modeling and Damping Coefficients on Cabin Noise

    Institute of Scientific and Technical Information of China (English)

    郑律; 朱锐

    2014-01-01

    文章基于统计能量法(SEA)开展了声学覆盖层敷设位置对舱室噪声的影响研究,探讨了不同损耗因子对舱室噪声的影响,计算对比表明阻尼损失系数发生改变时,声学覆盖层的抑振降噪效果亦将发生改变。%In combination with SEA, this article, based on an analysis of the influence of the laying position of the acoustic layer on cabin noise, studies the influence of different dissipation factors on cabin noise, the re-sults of which indicate that the changes of the damping coefficients have a great effect on the vibration damping and noise reduction of the acoustic layer.

  4. Noise measurements in the specific locations of traffic-engineering measures

    OpenAIRE

    Smejtek, Daniel

    2016-01-01

    This thesis deals with measurements of noise generated by road traffic. In theoretical part is described physical essence of sound, sound spread, perception of sound by human, effects of noise on human, methods of noise reduction, sources of noise from road traffic, legislation regarding noise and traffic-engineering measures. In practical part the noise was measured. Evaluate the noise at the bus stop, different noise level on straight road and sleeping policeman and different noise level on...

  5. Noise Pollution

    Science.gov (United States)

    ... Search Clean Air Act Overview Share Facebook Twitter Google+ Pinterest Contact Us Clean Air Act Title IV - ... noises in the community (from your neighbor, boom cars, lawn equipment, etc.) and from commercial businesses (factory, ...

  6. Active noise control primer

    CERN Document Server

    Snyder, Scott D

    2000-01-01

    Active noise control - the reduction of noise by generating an acoustic signal that actively interferes with the noise - has become an active area of basic research and engineering applications. The aim of this book is to present all of the basic knowledge one needs for assessing how useful active noise control will be for a given problem and then to provide some guidance for designing, setting up, and tuning an active noise-control system. Written for students who have no prior knowledge of acoustics, signal processing, or noise control but who do have a reasonable grasp of basic physics and mathematics, the book is short and descriptive. It leaves for more advanced texts or research monographs all mathematical details and proofs concerning vibrations, signal processing and the like. The book can thus be used in independent study, in a classroom with laboratories, or in conjunction with a kit for experiment or demonstration. Topics covered include: basic acoustics; human perception and sound; sound intensity...

  7. Influence of intralipid on free propofol fraction assayed in human serum albumin solutions and human plasma

    Institute of Scientific and Technical Information of China (English)

    Rafal KALITYNSKI; Andrzej L DAWIDOWICZ; Jacek POSZYTEK

    2006-01-01

    Aim: It is generally assumed that only unbound drugs can reach the site of action by diffusing across the membranes and exerting pharmacological effects by interacting with receptors. Recent research has shown that the percentage of free drugs may depend on the total drug concentration. The aim of the paper is to verify whether the mentioned dependence reported for propofol also takes place in plasma and human serum albumin samples in the presence of intralipid-the medium used as a vehicle for propofol infusions and a parenteral nutrition agent. Methods: Artificial plasma samples and human plasma were spiked with intralipid or ethanolic solutions of propofol. The samples were then assayed for free propofol concentration using ultrafiltration and high performance liquid chromatography with fluorimetric detection. Results: The decrease of the total drug concentration results in free propofol fraction increase, irrespectively of the used type of propofol solvent and sample type. The addition of intralipid causes the lowering of the overall free drug fraction with respect to the samples spiked with ethanolic solutions of the drug. Conclusion: The presence of intralipid does not influence the phenomenon of free propofol fraction rise at low total drug concentration. Such a rise cannot be ignored in clinical conditions when the drug is applied for sedative, antiemetic or other low-dosage purposes.

  8. 铁路混凝土箱梁箱内空腔共鸣噪声及其影响研究%Study on Cavity Resonance Noise of Railway Concrete Box-Girder and Its Influence

    Institute of Scientific and Technical Information of China (English)

    张迅; 王党雄; 李小珍

    2015-01-01

    为探讨铁路混凝土箱梁箱内空腔共鸣噪声及其影响,以某客运专线32 m预应力混凝土简支箱梁为研究对象,开展实桥振动与噪声试验,分析箱梁振动与噪声的时域特性及频谱特性。采用有限元法建立三维空腔声模型,分析箱内空腔声模态与腔内噪声峰值的关联性。采用边界元法分别建立两端封闭与两端开口的箱梁声学模型,验证箱内空腔共鸣噪声的来源及其影响。结果表明:在特定行车速度下,箱内噪声出现“拍”现象,显著增大箱内噪声,瞬时最大声压可达40 Pa,峰值频率为75.0 Hz;箱内噪声的“拍”现象来源于顶板的振动噪声,顶板的振动峰值频率与箱内空腔垂向声模态频率吻合时,箱内噪声显著增大;由于梁缝的声泄漏特性,箱内空腔共鸣噪声在梁缝处衰减较大,但其对桥梁两侧总体噪声的影响不可忽略。%In order to study the cavity resonance noise of concrete box-girder and its influence,a field test con-cerning vibration and noise of a 32 m PC simply-supported box-girder was carried out,to investigate the time-domain characteristics and frequency spectrum characteristics of vibration and noise of the box-girder.A 3D cavity acoustical model was established based on FEM to analyze the correlation between cavity acoustic mode and cavity noise peak.Two acoustical models for box-girders with closed ends and open ends,were built based on BEM,respectively,to verify the source and influence of cavity resonance noise.Results showed that the“beat”wave phenomenon of cavity noise appeared under a specific train speed,significantly increasing the cavi-ty noise,with the transient maximum sound pressure of cavity noise reaching 40 Pa and the noise peak frequen-cy being 75.0 Hz;The “beat”wave phenomenon of cavity noise derived from the vibration of deck.When the peak vibration frequency of deck matched with the frequency of vertical acoustic modal of the cavity

  9. The influence of flow conditions on the wide-band noise of an axial blower; Der Einfluss der Zustroembedingungen auf das breitbandige Geraeusch eines Axialventilators

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, M.

    2006-07-01

    Blower noise is calculated using semi-empirical methods presented in the relevant literature, and the results are compared with measurements. The noise fractions of the various sources are calculated separately in this method, and the results are then put together, also spectrally. One focal aspect was the investigation of the mechanism ''interaction of fan blades with inflow turbulence'', which is a dominant noise mechanism even if the degree of turbulence is still relatively low. Hot wire measurements served to provide information on the characteristic turbulence parameters of different flow configurations towards the fan, which were used as input variables in the noise calculation methods. The forecasted spectral noise levels as well as the total noise levels were in satisfactory agreement with measurements for all flow configurations investigated. (orig.)

  10. Influence of Magnetite Nanoparticles on Human Leukocyte Activity

    Science.gov (United States)

    Džarová, Anežka; Dubničková, Martina; Závišová, Vlasta; Koneracká, Martina; Kopčanský, Peter; Gojzewski, Hubert; Timko, Milan

    2010-12-01

    Chemically synthesized magnetite particles coated by sodium oleate and PEG (MNP), and magnetosomes (MS) influence the process of phagocytosis and the metabolic activity (lysozyme and peroxidase activity) in leukocytes. Lysozyme activity is oxygen-independent liquidation mechanisms of engulfed microorganism, peroxidase activity is an oxygen-dependent mechanism. Both tested types of nanoparticles lysed leukocyte cells during incubation. MNP at concentrations of 10 and 20 μg/mL lysed almost all leukocytes and their cell viability was in the 14±0.05% range. On the other hand MS begin to influence leukocytes activity at the concentration of 1 μg/ml and this influence grows with increasing concentration up to 20 μg/ml. MS are more suitable for biological applications than MNP which are more aggressive material than MS. MS should not be used above 10 μg/mL.

  11. Influence of spectral resolution, spectral range and signal-to-noise ratio of Fourier transform infra-red spectra on identification of high explosive substances.

    Science.gov (United States)

    Banas, Krzysztof; Banas, Agnieszka M; Heussler, Sascha P; Breese, Mark B H

    2018-01-05

    In the contemporary spectroscopy there is a trend to record spectra with the highest possible spectral resolution. This is clearly justified if the spectral features in the spectrum are very narrow (for example infra-red spectra of gas samples). However there is a plethora of samples (in the liquid and especially in the solid form) where there is a natural spectral peak broadening due to collisions and proximity predominately. Additionally there is a number of portable devices (spectrometers) with inherently restricted spectral resolution, spectral range or both, which are extremely useful in some field applications (archaeology, agriculture, food industry, cultural heritage, forensic science). In this paper the investigation of the influence of spectral resolution, spectral range and signal-to-noise ratio on the identification of high explosive substances by applying multivariate statistical methods on the Fourier transform infra-red spectral data sets is studied. All mathematical procedures on spectral data for dimension reduction, clustering and validation were implemented within R open source environment. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Multinational Parent Companies' Influence over Human Resource Decisions of Affiliates: U.S. Firms in Mexico

    OpenAIRE

    Zaida L. Martinez; David A Ricks

    1989-01-01

    This study provides empirical evidence for the relationship between the degree of influence U.S. parent companies have over the human resource decisions of their Mexican affiliates and the affiliates' resource dependencies on the parent company. Both wholly-owned and Joint venture affiliates are examined. Resource dependence was the factor most closely related to parent influence over affiliate human resource decisions. The importance of an affiliate to a parent company, the nationality of af...

  13. INFLUENCE OF VIBRATIONS AND DYNAMIC CHARACTERIZATION OF THE HUMAN BODY GENERATED BY CARS

    Directory of Open Access Journals (Sweden)

    Bogdan Andrei BARBU

    2011-05-01

    Full Text Available Vibrations influence the human body in many different ways. The response to a vibration exposure is primarily dependent on the frequency, amplitude, and duration of exposure. This paper studies the influence of vibrations generated by automobiles on the human body, taking into account both amplitude and especially the frequency of these vibrations. Measurement of these vibrations was made through the acquisition of latest equipment by acquiring tridimensional signals.

  14. Road Traffic Noise

    Science.gov (United States)

    Beckenbauer, Thomas

    Road traffic is the most interfering noise source in developed countries. According to a publication of the European Union (EU) at the end of the twentieth century [1], about 40% of the population in 15 EU member states is exposed to road traffic noise at mean levels exceeding 55 dB(A). Nearly 80 million people, 20% of the population, are exposed to levels exceeding 65 dB(A) during daytime and more than 30% of the population is exposed to levels exceeding 55 dB(A) during night time. Such high noise levels cause health risks and social disorders (aggressiveness, protest, and helplessness), interference of communication and disturbance of sleep; the long- and short-term consequences cause adverse cardiovascular effects, detrimental hormonal responses (stress hormones), and possible disturbance of the human metabolism (nutrition) and the immune system. Even performance at work and school could be impaired.

  15. Noise and Tinnitus

    Directory of Open Access Journals (Sweden)

    Mansoureh Adel Ghahraman

    1999-03-01

    Full Text Available Tinnitus from the Latin word tinnire meaning ringing is the perception of sound within the human ear in the absence of corresponding external sound. The most common cause is noise induced hearing loss. Tinnitus may be induced by an acoustic trauma or a permanent noise in the workplace. In case that Tinnitus is induced by acoustic trauma the site of lesion is commonly the base of the cochlea. Tinnitus in the senile population is mostly accompanying presbycusis. Although the incidence of permanent tinnitus following noise exposure is high, little is published about this issue. In the current article we are aimed at studying the prevalence of tinnitus in Minoo and other manufactures.

  16. Variables influencing the frictional behaviour of in vivo human skin.

    Science.gov (United States)

    Veijgen, N K; Masen, M A; van der Heide, E

    2013-12-01

    In the past decades, skin friction research has focused on determining which variables are important to affect the frictional behaviour of in vivo human skin. Until now, there is still limited knowledge on these variables. This study has used a large dataset to identify the effect of variables on the human skin, subject characteristics and environmental conditions on skin friction. The data are obtained on 50 subjects (34 males and 16 females). Friction measurements represent the friction between in vivo human skin and an aluminium sample, assessed on three anatomical locations. The coefficient of friction increased significantly (pskin and the height of the subject. Other outcome variables in this study were the hydration of the skin and the skin temperature.

  17. bFGF influences human articular chondrocyte differentiation

    DEFF Research Database (Denmark)

    Schmal, H; Zwingmann, J; Fehrenbach, M

    2007-01-01

    FGF concentrations in supernatants of primary human articular chondrocytes peaked immediately after isolation and then declined. In a dose-dependent manner, bFGF enhanced cell amplification and viability. BFGF induced a decrease in the apoptotic cell population, while the number of proliferating cells remained......BACKGROUND: The possible functional role of basic fibroblast growth factor (bFGF) in regulating the mitotic and metabolic activity of primary human articular chondrocytes was investigated. METHODS: [EF1]Chondrocytes were enzymatically isolated from femoral head cartilage, and were cultured in vitro...

  18. Chronic Heat Stress and Cognitive Development: An Example of Thermal Conditions Influencing Human Development

    Science.gov (United States)

    Riniolo, Todd C.; Schmidt, Louis A.

    2006-01-01

    Although thermal conditions influence the development of living organisms in a wide variety of ways, this topic has been recently ignored in humans. This paper reintroduces thermal conditions as a topic of importance for developmentalists by presenting an example of how thermal conditions are hypothesized to influence a particular developmental…

  19. Improving human performance: Industry factors influencing the ability to perform

    Directory of Open Access Journals (Sweden)

    Güera Massyn Romo

    2013-03-01

    Full Text Available Learning interventions and new technologies that aim to improve human performance must take cognisance of industry factors inhibiting human performance. The dynamic and fast pace nature of the Information and Communication Technologies (ICT and the engineering industries do not lend themselves to proper skills planning and management. These industries experience real skills gaps, to some of which they contribute by themselves. This study reports on these performance-inhibiting factors such as the underutilisation of available skills, tolerance for individual preferences, and dynamically, and informally refining a role objective while an employee is occupying a certain role. The important professional skills required by individuals to cope with these real life factors are also explored in the skills gaps management context. Moreover, these industries need a profile they refer to as Special Forces, which denotes a high calibre of worker that possesses well-developed professional skills whilst having advanced technical expertise and sufficient experience. This resource profile is required largely due to the poor management of human resource processes in practice and the current reported lack of adequate skills. Furthermore, this study refers to the recent lack of a working definition for these Special Forces leading to the omitted active development of these profiles in industry today, which appears to become a key human performance inhibiting factor.

  20. Learned predictiveness influences automatic evaluations in human contingency learning

    NARCIS (Netherlands)

    Le Pelley, M. E.; Calvini, G.; Spears, R.

    2013-01-01

    Experiments used an affective priming procedure to investigate whether evaluative conditioning in humans is subject to bias as a consequence of differences in the learned predictiveness of the cues involved. Experiment 1, using brief prime presentation, demonstrated stronger affective priming for

  1. Variables influencing the frictional behaviour of in vivo human skin

    NARCIS (Netherlands)

    Veijgen, N.K.; Masen, M.A.; Heide, van der E.

    2013-01-01

    In the past decades, skin friction research has focused on determining which variables are important to affect the frictional behaviour of in vivo human skin. Until now, there is still limited knowledge on these variables. This study has used a large dataset to identify the effect of variables on t

  2. Variables influencing the frictional behaviour of in vivo human skin

    NARCIS (Netherlands)

    Veijgen, N.K.; Masen, M.A.; Heide, E. van der

    2013-01-01

    In the past decades, skin friction research has focused on determining which variables are important to affect the frictional behaviour of in vivo human skin. Until now, there is still limited knowledge on these variables.This study has used a large dataset to identify the effect of variables on the

  3. Learned predictiveness influences automatic evaluations in human contingency learning

    NARCIS (Netherlands)

    Le Pelley, M. E.; Calvini, G.; Spears, R.

    2013-01-01

    Experiments used an affective priming procedure to investigate whether evaluative conditioning in humans is subject to bias as a consequence of differences in the learned predictiveness of the cues involved. Experiment 1, using brief prime presentation, demonstrated stronger affective priming for cu

  4. Hypnosis and Human Development: Interpersonal Influence of Intrapersonal Processes.

    Science.gov (United States)

    Vandenberg, Brian

    1998-01-01

    Examines the relationship between hypnosis and human development. Defines hypnosis within a communications framework, and identifies essential features of hypnosis in the communicative exchanges of the first months of life; this forces a reconsideration of the understanding of the ontogenesis of hypnosis. Identifies four key features of hypnosis,…

  5. Endogenous collagen influences differentiation of human multipotent mesenchymal stromal cells

    NARCIS (Netherlands)

    Fernandes, H.; Mentink, A.; Bank, R.; Stoop, R.; Blitterswijk, C. van; Boer, J. de

    2010-01-01

    Human multipotent mesenchymal stromal cells (hMSCs) are multipotent cells that, in the presence of appropriate stimuli, can differentiate into different lineages such as the osteogenic, chondrogenic, and adipogenic lineages. In the presence of ascorbic acid, MSCs secrete an extracellular matrix main

  6. Hypnosis and Human Development: Interpersonal Influence of Intrapersonal Processes.

    Science.gov (United States)

    Vandenberg, Brian

    1998-01-01

    Examines the relationship between hypnosis and human development. Defines hypnosis within a communications framework, and identifies essential features of hypnosis in the communicative exchanges of the first months of life; this forces a reconsideration of the understanding of the ontogenesis of hypnosis. Identifies four key features of hypnosis,…

  7. 钢弹簧浮置板轨道对车内噪声影响的实测与分析%Measurement and Analysis of Influence of Steel Spring Floating Slab Track on Vehicle Interior Noise

    Institute of Scientific and Technical Information of China (English)

    肖安鑫; 田野

    2012-01-01

    When a train passes through on steel spring floating slab, intermediate and low frequency noises will be generated in its vehicles. Such noises will reduce the traveling comfort. In this paper, the vehicle' s interior noises of floating slab in different tracks are compared and analyzed. The influence of steel spring floating slab track on vehicle' s interior noise is analyzed. The results show that the floating slab track with high damping steel spring can effectively reduce the interior noise.%在列车经过钢弹簧浮置板地段时,车内产生中低频噪声,影响着人们乘车环境舒适性.通过对不同钢弹簧浮置板轨道地段车内噪声的对比测试,分析钢弹簧浮置板轨道对车内噪声的影响,结果表明采用高阻尼钢弹簧浮置板轨道可有效降低车内噪声.

  8. Metabolic and Sensory Influences on Odor Sensitivity in Humans.

    Science.gov (United States)

    Ramaekers, Marielle G; Verhoef, Alard; Gort, Gerrit; Luning, Pieternel A; Boesveldt, Sanne

    2016-02-01

    Our olfactory sense plays an important role in eating behavior by modulating our food preferences and intake. However, hunger or satiety may also influence how we perceive odors. Albeit speculative, contradictory results found in the past may have resulted from confounding by type of meal that participants ate to induce satiety. We aimed to investigate the influence of hunger state on olfactory sensitivity, comparing hunger to satiety using 2 different types of lunch to control for sensory-specific satiety. Odor detection thresholds were measured in 2 groups of participants (39 per group, 18-40 years), under 3 conditions: when hungry (twice), after a sweet lunch, and after a savory lunch. One group had their detection thresholds tested for a sweet odor, whereas in the other group, sensitivity to a savory odor was measured. Differences in olfactory sensitivity conditions were analyzed using linear mixed models. Participants had higher scores on the odor sensitivity task in a hungry versus satiated state (P = 0.001). Within the satiated condition, there was no effect of type of lunch on odor sensitivity. In conclusion, hunger slightly enhances sensitivity to food odors, but did not significantly depend on the type of food participants ate, suggesting no clear influence of sensory-specific satiety.

  9. Noise radar with broadband microwave ring correlator

    Science.gov (United States)

    Susek, Waldemar; Stec, Bronislaw

    2011-06-01

    A principle of quadrature correlation detection of noise signals using an analog broadband microwave correlator is presented in the paper. Measurement results for the correlation function of noise signals are shown and application of such solution in the noise radar for precise determination of distance changes and velocity of these changes is also presented. Results for short range noise radar operation are presented both for static and moving objects. Experimental results using 2,6 - 3,6 GHz noise like waveform for the signal from a breathing human is presented. Conclusions and future plans for applications of presented detection technique in broadband noise radars bring the paper to an end.

  10. The associations between noise sensitivity, reported physical and mental health, perceived environmental quality, and noise annoyance

    Directory of Open Access Journals (Sweden)

    Dirk Schreckenberg

    2010-01-01

    Full Text Available One hundred and ninety residents around Frankfurt Airport (46% female; 17-80 years were interviewed concerning noise annoyance due to transportation noise (aircraft, road traffic, perceived mental and physical health, perceived environmental quality, and noise sensitivity. The aim of the analyses was to test whether noise sensitivity reflects partly general environmental sensitivity and is associated with an elevated susceptibility for the perception of mental and physical health. In this study, the reported physical and mental health variables were not associated with noise exposure but with noise annoyance, and were interpreted to reflect nonspecific codeterminants of annoyance rather than noise effects. Noise sensitivity was found to influence total noise annoyance and aircraft noise annoyance but to a lesser degree annoyance due to road traffic noise. Noise sensitivity was associated with reported physical health, but not with reported mental health. Noise-sensitive persons reported poorer environmental quality in their residential area than less sensitive persons in particular with regard to air traffic (including the facets noise, pollution, and contaminations and quietness. Other aspects of the perceived quality of the environment were scarcely associated with noise sensitivity. This indicates that noise sensitivity is more specific and a reliable predictor of responses to noise from the dominant source (in this case air traffic rather than a predictor of the individual perception of the environmental quality in general.

  11. The associations between noise sensitivity, reported physical and mental health, perceived environmental quality, and noise annoyance.

    Science.gov (United States)

    Schreckenberg, Dirk; Griefahn, Barbara; Meis, Markus

    2010-01-01

    One hundred and ninety residents around Frankfurt Airport (46% female; 17-80 years) were interviewed concerning noise annoyance due to transportation noise (aircraft, road traffic), perceived mental and physical health, perceived environmental quality, and noise sensitivity. The aim of the analyses was to test whether noise sensitivity reflects partly general environmental sensitivity and is associated with an elevated susceptibility for the perception of mental and physical health. In this study, the reported physical and mental health variables were not associated with noise exposure but with noise annoyance, and were interpreted to reflect nonspecific codeterminants of annoyance rather than noise effects. Noise sensitivity was found to influence total noise annoyance and aircraft noise annoyance but to a lesser degree annoyance due to road traffic noise. Noise sensitivity was associated with reported physical health, but not with reported mental health. Noise-sensitive persons reported poorer environmental quality in their residential area than less sensitive persons in particular with regard to air traffic (including the facets noise, pollution, and contaminations) and quietness. Other aspects of the perceived quality of the environment were scarcely associated with noise sensitivity. This indicates that noise sensitivity is more specific and a reliable predictor of responses to noise from the dominant source (in this case air traffic) rather than a predictor of the individual perception of the environmental quality in general.

  12. Influence of socio-cultural modernization on development of human capital assets in Russia

    Directory of Open Access Journals (Sweden)

    2014-01-01

    Full Text Available The paper presents major points of research into socio-cultural conditions of human capital assets accumulation in Russia. Notion of social justice, social responsibility of business, realization of their role as “vehicle of capital” by employees, national mentality – all this essentially influences on efficiency of human capital assets accumulation in Russia.

  13. Couple Reports of the Perceived Influences of a College Human Sexuality Course: An Exploratory Study

    Science.gov (United States)

    Henry, Dayna S.

    2013-01-01

    Research on the effects of college sexuality education has been largely quantitative in nature and has focused on changes in individual attitudes, behaviours and knowledge. This study sought to explore, qualitatively, the influences of enrolment in a human sexuality course on relationships. Eight couples from an undergraduate human sexuality…

  14. Stereology of human myometrium in pregnancy: influence of maternal body mass index and age.

    LENUS (Irish Health Repository)

    Sweeney, Eva M

    2013-04-01

    Knowledge of the stereology of human myometrium in pregnancy is limited. Uterine contractile performance may be altered in association with maternal obesity and advanced maternal age. The aim of this study was to investigate the stereology of human myometrium in pregnancy, and to evaluate a potential influence of maternal body mass index (BMI) and age.

  15. The problem of noise in weaving mills. [considering sound absorbing ceiling

    Science.gov (United States)

    Georgescu, T.; Harastaseanu, E.; Mercea, F.

    1974-01-01

    In weaving mill departments equipped with shuttle looms there exists a high noise level that has a noxious effect on the human organism, a fact which affects a very great number of employees and has negative repercussions on productivity. Measurements were conducted in different weaving mills to determine the noise level as well as the influence of some factors that depend on the type of construction, the type, number and manner of operation of the looms, etc. Solutions for noise reduction were established that were applied experimentally in some weaving mills, and the results obtained are discussed.

  16. Simulating Food Web Dynamics along a Gradient: Quantifying Human Influence

    OpenAIRE

    Ferenc Jordán; Nerta Gjata; Shu Mei; Yule, Catherine M.

    2012-01-01

    Realistically parameterized and dynamically simulated food-webs are useful tool to explore the importance of the functional diversity of ecosystems, and in particular relations between the dynamics of species and the whole community. We present a stochastic dynamical food web simulation for the Kelian River (Borneo). The food web was constructed for six different locations, arrayed along a gradient of increasing human perturbation (mostly resulting from gold mining activities) along the river...

  17. The Influence of Human Factor in Aircraft Maintenance

    Directory of Open Access Journals (Sweden)

    Darko Virovac

    2017-06-01

    during aircraft maintenance. In the EASA approved aircraft maintenance organisation, which includes in its working system the human factor as well, the tendency is to apply the approach by continuous monitoring and analysis of errors in aircraft maintenance. Such approach achieves advance prevention or reduction of the occurrence of harmful events, such as accidents, incidents, injuries and in a wider sense damages related to aircraft operation and maintenance. The research presented in this paper is a result of gathering and systematization of errors caused by human factors over the last five years in one organisation for aircraft maintenance certified according to the European standards. The study encompasses an analysis of 28 (twenty-eight investigations of individual cases and provides insight into the main factors of errors. The results of analyses on the cause of occurrence of human error show similar results like the Boeing study which was carried out for the world fleet.

  18. Noise Pollution and Health Effects

    Directory of Open Access Journals (Sweden)

    Geravandi

    2015-01-01

    Full Text Available Background Noise pollution is of particular importance due to the physical and psychological effects on humans. Noise is a stressor that affects the autonomic nervous system and the endocrine system. Noise is also a threat to marine and terrestrial ecosystems. Health risks from noise are correlated with road traffic. In other words, noise health effects are the health consequences of elevated sound levels. Objectives This study aims to determine the effect of noise pollution (near roadways on health issues in Ahvaz, Iran. Materials and Methods In this cross-sectional study, equivalent sound pressure level were measured by sound level meters TES-1353 in 75 locations around 4 roadways, which had a high load of traffic in Ahvaz City during day time. During the study, 820 measurements were recorded at measuring stations, for 7 days per week with 1-hour interval between each measurement. Statistical analysis was carried out by SPSS software. Results According to the research findings, the equivalent sound pressure levels in all stations were 76.28 ± 3.12 dB (Mean ± SD. According to sound measurements and the survey questionnaire, noise pollution is higher than EPA (US Environmental Protection Agency and Iran standard level. Based on result of this study the worst noise health effects were the nervousness and sleep quality during 2012. Conclusions According to the results of this study, with increasing load of traffic, there is an increasing need for proper consideration plans to control noise pollution and prevent its effects.

  19. Integrating social networks and human social motives to achieve social influence at scale

    Science.gov (United States)

    Contractor, Noshir S.; DeChurch, Leslie A.

    2014-01-01

    The innovations of science often point to ideas and behaviors that must spread and take root in communities to have impact. Ideas, practices, and behaviors need to go from accepted truths on the part of a few scientists to commonplace beliefs and norms in the minds of the many. Moving from scientific discoveries to public good requires social influence. We introduce a structured influence process (SIP) framework to explain how social networks (i.e., the structure of social influence) and human social motives (i.e., the process of social influence wherein one person’s attitudes and behaviors affect another’s) are used collectively to enact social influence within a community. The SIP framework advances the science of scientific communication by positing social influence events that consider both the “who” and the “how” of social influence. This framework synthesizes core ideas from two bodies of research on social influence. The first is network research on social influence structures, which identifies who are the opinion leaders and who among their network of peers shapes their attitudes and behaviors. The second is research on social influence processes in psychology, which explores how human social motives such as the need for accuracy or the need for affiliation stimulate behavior change. We illustrate the practical implications of the SIP framework by applying it to the case of reducing neonatal mortality in India. PMID:25225373

  20. The influence of acoustical and non-acoustical factors on short-term annoyance due to aircraft noise in the field - The COSMA study.

    Science.gov (United States)

    Bartels, Susanne; Márki, Ferenc; Müller, Uwe

    2015-12-15

    Air traffic has increased for the past decades and is forecasted to continue to grow. Noise due to current airport operations can impair the physical and psychological well-being of airport residents. The field study investigated aircraft noise-induced short-term (i.e., within hourly intervals) annoyance in local residents near a busy airport. We aimed at examining the contribution of acoustical and non-acoustical factors to the annoyance rating. Across four days from getting up till going to bed, 55 residents near Cologne/Bonn Airport (M=46years, SD=14years, 34 female) rated their annoyance due to aircraft noise at hourly intervals. For each participant and each hour, 26 noise metrics from outdoor measurements and further 6 individualized metrics that took into account the sound attenuation due to each person's whereabouts in and around their homes were obtained. Non-acoustical variables were differentiated into situational factors (time of day, performed activity during past hour, day of the week) and personal factors (e.g., sensitivity to noise, attitudes, domestic noise insulation). Generalized Estimation Equations were applied for the development of a prediction model for annoyance. Acoustical factors explained only a small proportion (13.7%) of the variance in the annoyance ratings. The number of fly-overs predicted annoyance better than did equivalent and maximum sound pressure levels. The proportion of explained variance in annoyance rose considerably (to 27.6%) when individualized noise metrics as well as situational and personal variables were included in the prediction model. Consideration of noise metrics related to the number of fly-overs and individual adjustment of noise metrics can improve the prediction of short-term annoyance compared to models using equivalent outdoor levels only. Non-acoustical factors have remarkable impact not only on long-term annoyance as shown before but also on short-term annoyance judged in the home environment. Copyright

  1. Relationship between the field local quadrature and the quantum discord of a photon-added correlated channel under the influence of scattering and phase fluctuation noise

    Science.gov (United States)

    Domínguez-Serna, Francisco A.; Mendieta-Jimenez, Francisco J.; Rojas, Fernando

    2017-10-01

    We study quantum correlations and discord in a bipartite continuous variable hybrid system formed by linear combinations of coherent states \\mathinner {|{α }\\rangle } and single photon-added coherent states of the form \\mathinner {|{ψ }\\rangle }_{ {dp(pa)}}= \\mathcal {N}/√{2} (\\hat{a}^\\dagger \\mathinner {|{α }\\rangle }_a\\mathinner {|{α }\\rangle }_b ± \\hat{b}^\\dagger \\mathinner {|{α }\\rangle }_a\\mathinner {|{α }\\rangle }_b). We stablish a relationship between the quantum discord with a local observable (the quadrature variance for one subsystem) under the influence of scattering and phase fluctuation noise. For the pure states the quantum correlations are characterized by means of measurement induced disturbance (MID) with simultaneous quadrature measurements. In a scenario where homodyne conditional measurements are available we show that the MID provides an easy way to select optimal phases to obtain information of the maximal correlations in the channels. The quantum correlations of these entangled states with channel losses are quantitatively characterized with the quantum discord (QD) with a displaced qubit projector. We observe that as scattering increases, QD decreases monotonically. At the same time for the state \\mathinner {|{ψ }\\rangle }_{ {dp}}, QD is more resistant to high phase fluctuations when the average photon number n_0 is bigger than zero, but if phase fluctuations are low, QD is more resistant if n_0=0. For the dp model with scattering, we obtain an analytical expression of the QD as a function of the observable quadrature variance in a local subsystem. This relation allows us to have a way to obtain the degree of QD in the channel by just measuring a local property observable such as the quadrature variance. For the other model this relation still exists but is explored numerically. This relation is an important result that allows to identify quantum processing capabilities in terms of just local observables.

  2. Organophosphorus flame retardants – Toxicity and influence on human health

    Directory of Open Access Journals (Sweden)

    Elżbieta Bruchajzer

    2015-06-01

    Full Text Available Organophosphorus flame retardants (flame retardants, FRs have been used for several decades in many industries, including the production of dyes, varnishes, adhesives, synthetic resins, polyvinyl chloride, hydraulic fluids, plastics and textiles. Their importance in recent times has increased due to i.a., significantly reduced use of polybrominated diphenyl ethers (PBDEs – persistent organic pollutants, dangerous for the environment. The aim of this study was to review the available literature data concerning phosphorous FRs primarily for neurotoxic, fertility, reproductive and carcinogenic effects. The analysis concerned the following most commonly used substances: tris(2-ethylhexylphosphate (TEHP, tris(2-butoxyethylphosphate (TBEP, triphenyl phosphate (TPP, tris(2-chloroethylphosphate (TCEP, tetrakis(hydroxymethyl-phosphonium chloride (THPC, tributyl phosphate (TBP, tricresyl phosphate (TCP, tris(2-chloroisopropylphosphate (TCPP, tris(1,3-dichloroisopropylphosphate (TDCP and tetrakis(hydroxymethyl phosphonium sulphate (THPS. In animal studies neurotoxic effects were found after exposure to TBEP, THPC, TBP and TCP, while in humans they were observed only after exposure to TCP. TCEP, THPS, TBP, TCP and TDCP caused disorders in fertility and/or fetal development of animals. Adverse effects on reproduction in humans may be caused by TPP, TCP, and TDCP. In laboratory animals the development of tumors was observed after high doses of TEHP, TCEP, TBP and TDCP. None of these compounds is classified as a human carcinogen. The environmental toxicity of phosphate FRs is low (except for TPP, TCEP and TBEP. They are not stable compounds, in living organisms they are metabolised and quickly excreted. Therefore, they can be used as an alternative to PBDEs. Med. Pr. 2015;66(2:235–264

  3. [ORGANOPHOSPHORUS FLAME RETARDANTS - TOXICITY AND INFLUENCE ON HUMAN HEALTH].

    Science.gov (United States)

    Bruchajzer, Elżbieta; Frydrych, Barbara; Szymańska, Jadwiga Anna

    2015-01-01

    Organophosphorus flame retardants (flame retardants, FRs) have been used for several decades in many industries, including the production of dyes, varnishes, adhesives, synthetic resins, polyvinyl chloride, hydraulic fluids, plastics and textiles. Their importance in recent times has increased due to i.a., significantly reduced use of polybrominated diphenyl ethers (PBDEs) - persistent organic pollutants, dangerous for the environment. The aim of this study was to review the available literature data concerning phosphorous FRs primarily for neurotoxic, fertility, reproductive and carcinogenic effects. The analysis concerned the following most commonly used substances: tris(2-ethylhexyl)phosphate (TEHP), tris(2-butoxyethyl)phosphate (TBEP), triphenyl phosphate (TPP), tris(2-chloroethyl)phosphate (TCEP), tetrakis(hydroxymethyl)-phosphonium chloride (THPC), tributyl phosphate (TBP), tricresyl phosphate (TCP), tris(2-chloroisopropyl)phosphate (TCPP), tris(1,3-dichloroisopropyl)phosphate (TDCP) and tetrakis(hydroxymethyl)phosphonium sulphate (THPS). In animal studies neurotoxic effects were found after exposure to TBEP, THPC, TBP and TCP, while in humans they were observed only after exposure to TCP. TCEP, THPS, TBP, TCP and TDCP caused disorders in fertility and/or fetal development of animals. Adverse effects on reproduction in humans may be caused by TPP, TCP, and TDCP. In laboratory animals the development of tumors was observed after high doses of TEHP, TCEP, TBP and TDCP. None of these compounds is classified as a human carcinogen. The environmental toxicity of phosphate FRs is low (except for TPP, TCEP and TBEP). They are not stable compounds, in living organisms they are metabolised and quickly excreted. Therefore, they can be used as an alternative to PBDEs.

  4. Human solvent exposure. Factors influencing the pharmacokinetics and acute toxicity

    DEFF Research Database (Denmark)

    Bælum, Jesper

    1991-01-01

    exposed to mixtures of solvents experience an increased frequency of work related irritative and neurological symptoms although the exposure has been far below the occupational exposure limits. A series of controlled human exposure studies was carried out. Different groups of persons were exposed...... to the most frequent solvent, toluene. Toluene in alveolar air and the urinary excretion of the metabolites were measured and the acute effects of toluene were assessed by the performance in a series of test of the perceptual and psychomotor functions as well as a standardized registration of annoyance...

  5. Influence of a constant magnetic field on human lymphocyte cultures.

    Science.gov (United States)

    Ardito, G; Lamberti, L; Bigatti, P; Prono, G

    1984-07-31

    The growing exposure to magnetic fields of a certain intensity could represent a serious hazard for our health. In the present note we analyze the effect of a 740 Gauss magnetic field on human lymphocyte cell cultures. From the analysis of our data it is possible to point out that this field produces an inhibition of the cell growth, while does not affect at all the sister chromatid exchange frequency of the chromosomes. Conversely we found a significant increase of chromosome aberrations in the exposed cells. The chromosome aberrations found were mostly gaps and breaks.

  6. Human influences on trophic cascades along rocky shores

    Science.gov (United States)

    Lindberg, D.R.; Estes, J.A.; Warheit, K.I.

    1998-01-01

    A three-trophic-level interaction among American Black Oystercatchers (Haematopus bachmani), limpets (Lottia spp.), and erect fleshy algae in rocky intertidal communities of central and southern California was documented via manipulative and 'natural' experiments. Removal of the territorial limpet (Lottia gigantea) initially caused large increases in the percent cover of erect fleshy algae, followed by a more gradual increase in density of small limpets (Lottia spp.) and a decline in algal cover. Algal cover increased following the removal of small limpets at the sites from which L. gigantea had been removed earlier, thus demonstrating that the large and small limpets had similar inhibitory effects on plant populations. A comparison of sites with and without oyster-catchers showed that L. gigantea occupied substrate inclinations in proportion to their availability at sites where oystercatchers were rare, whereas the distribution of L. gigantea was skewed toward vertically inclined substrates where oystercatchers were common. Survival rates of limpets translocated to horizontal and vertical substrates were similar in sites lacking oystercatcher predation, but were much lower on horizontal substrates where oystercatchers were common. Our results are consistent with those from several prior studies in demonstrating that shorelines frequented by humans typically lack oystercatchers. Humans also exploit L. gigantea and reduce populations to low densities of small individuals. These findings may explain why the midlittoral zone of rocky intertidal communities in western North America are so often dominated by high population densities of small limpets.

  7. Search strategy has influenced the discovery rate of human viruses.

    Science.gov (United States)

    Rosenberg, Ronald; Johansson, Michael A; Powers, Ann M; Miller, Barry R

    2013-08-20

    A widely held concern is that the pace of infectious disease emergence has been increasing. We have analyzed the rate of discovery of pathogenic viruses, the preeminent source of newly discovered causes of human disease, from 1897 through 2010. The rate was highest during 1950-1969, after which it moderated. This general picture masks two distinct trends: for arthropod-borne viruses, which comprised 39% of pathogenic viruses, the discovery rate peaked at three per year during 1960-1969, but subsequently fell nearly to zero by 1980; however, the rate of discovery of nonarboviruses remained stable at about two per year from 1950 through 2010. The period of highest arbovirus discovery coincided with a comprehensive program supported by The Rockefeller Foundation of isolating viruses from humans, animals, and arthropod vectors at field stations in Latin America, Africa, and India. The productivity of this strategy illustrates the importance of location, approach, long-term commitment, and sponsorship in the discovery of emerging pathogens.

  8. Human tolerance to heat strain during exercise: influence of hydration.

    Science.gov (United States)

    Sawka, M N; Young, A J; Latzka, W A; Neufer, P D; Quigley, M D; Pandolf, K B

    1992-07-01

    This study determined whether 1) exhaustion from heat strain occurs at the same body temperatures during exercise in the heat when subjects are euhydrated as when they are hypohydrated, 2) aerobic fitness influences the body temperature at which exhaustion from heat strain occurs, and 3) curves could be developed to estimate exhaustion rates at a given level of physiological strain. Seventeen heat-acclimated men [maximal oxygen uptake (VO2max) from 45 to 65 ml.kg-1.min-1] attempted two heat stress tests (HSTs): one when euhydrated and one when hypohydrated by 8% of total body water. The HSTs consisted of 180 min of rest and treadmill walking (45% VO2max) in a hot-dry (ambient temperature 49 degrees C, relative humidity 20%) environment. The required evaporative cooling (Ereq) exceeded the maximal evaporative cooling capacity of the environment (Emax); thus thermal equilibrium could not be achieved and 27 of 34 HSTs ended by exhaustion from heat strain. Our findings concerning exhaustion from heat strain are 1) hypohydration reduced the core temperature that could be tolerated; 2) aerobic fitness, per se, did not influence the magnitude of heat strain that could be tolerated; 3) curves can be developed to estimate exhaustion rates for a given level of physiological strain; and 4) exhaustion was rarely associated with a core temperature up to 38 degrees C, and it always occurred before a temperature of 40 degrees C was achieved. These findings are applicable to heat-acclimated individuals performing moderate-intensity exercise under conditions where Ereq approximates or exceeds Emax and who have high skin temperatures.

  9. Influence of organophosphate poisoning on human dendritic cells.

    Science.gov (United States)

    Schäfer, Marina; Koppe, Franziska; Stenger, Bernhard; Brochhausen, Christoph; Schmidt, Annette; Steinritz, Dirk; Thiermann, Horst; Kirkpatrick, Charles James; Pohl, Christine

    2013-12-05

    Organophosphourus compounds (OPC, including nerve agents and pesticides) exhibit acute toxicity by inhibition of acetylcholinesterase. Lung affections are frequent complications and a risk factor for death. In addition, epidemiological studies reported immunological alterations after OPC exposure. In our experiments we investigated the effects of organophosphourus pesticides dimethoate and chlorpyrifos on dendritic cells (DC) that are essential for the initial immune response, especially in the pulmonary system. DC, differentiated from the monocyte cell line THP-1 by using various cytokines (IL-4, GM-CSF, TNF-α, Ionomycin), were exposed to organophosphourus compounds at different concentrations for a 24h time period. DC were characterized by flow cytometry and immunofluorescence using typical dendritic cell markers (e.g., CD11c, CD209 and CD83). After OPC exposure we investigated cell death, the secretion profile of inflammatory mediators, changes of DC morphology, and the effect on protein kinase signalling pathways. Our results revealed a successful differentiation of THP-1 into DC. OPC exposure caused a significant concentration-dependent influence on DC: Dendrites of the DC were shortened and damaged, DC-specific cell surface markers (i.e., CD83and CD209) decreased dramatically after chlorpyrifos exposure. Interestingly, the effects caused by dimethoate were in general less pronounced. The organophosphourus compounds affected the release of inflammatory cytokines, such as IL-1ß and IL-8. The anti-inflammatory cytokine IL-10 was significantly down regulated. Protein kinases like the Akt family or ERK, which are essential for cell survival and proliferation, were inhibited by both OPC. These findings indicate that the tested organophosphourus compounds induced significant changes in cell morphology, inhibited anti-inflammatory cytokines and influenced important protein signalling pathways which are involved in regulation of apoptosis. Thus our results highlight

  10. Kurtosis corrected sound pressure level as a noise metric for risk assessment of occupational noises.

    Science.gov (United States)

    Goley, G Steven; Song, Won Joon; Kim, Jay H

    2011-03-01

    Current noise guidelines use an energy-based noise metric to predict the risk of hearing loss, and thus ignore the effect of temporal characteristics of the noise. The practice is widely considered to underestimate the risk of a complex noise environment, where impulsive noises are embedded in a steady-state noise. A basic form for noise metrics is designed by combining the equivalent sound pressure level (SPL) and a temporal correction term defined as a function of kurtosis of the noise. Several noise metrics are developed by varying this basic form and evaluated utilizing existing chinchilla noise exposure data. It is shown that the kurtosis correction term significantly improves the correlation of the noise metric with the measured hearing losses in chinchillas. The average SPL of the frequency components of the noise that define the hearing loss with a kurtosis correction term is identified as the best noise metric among tested. One of the investigated metrics, the kurtosis-corrected A-weighted SPL, is applied to a human exposure study data as a preview of applying the metrics to human guidelines. The possibility of applying the noise metrics to human guidelines is discussed.

  11. Noise-control needs in the developing energy technologies

    Energy Technology Data Exchange (ETDEWEB)

    Keast, D.N.

    1978-03-01

    The noise characteristics of existing energy conversion technologies, e.g., from obtaining and processing fossil fuels to power plants operations, and of developing energy technologies (wind, geothermal sources, solar energy or fusion systems) are discussed in terms of the effects of noise on humans, animals, structures, and equipment and methods for noise control. Regulations for noise control are described. Recommendations are made for further research on noise control and noise effects. (LCL)

  12. Noise Annoyance in Urban Children: A Cross-Sectional Population-Based Study

    Science.gov (United States)

    Grelat, Natacha; Houot, Hélène; Pujol, Sophie; Levain, Jean-Pierre; Defrance, Jérôme; Mariet, Anne-Sophie; Mauny, Frédéric

    2016-01-01

    Acoustical and non-acoustical factors influencing noise annoyance in adults have been well-documented in recent years; however, similar knowledge is lacking in children. The aim of this study was to quantify the annoyance caused by chronic ambient noise at home in children and to assess the relationship between these children′s noise annoyance level and individual and contextual factors in the surrounding urban area. A cross sectional population-based study was conducted including 517 children attending primary school in a European city. Noise annoyance was measured using a self-report questionnaire adapted for children. Six noise exposure level indicators were built at different locations at increasing distances from the child′s bedroom window using a validated strategic noise map. Multilevel logistic models were constructed to investigate factors associated with noise annoyance in children. Noise indicators in front of the child′s bedroom (p ≤ 0.01), family residential satisfaction (p ≤ 0.03) and socioeconomic characteristics of the individuals and their neighbourhood (p ≤ 0.05) remained associated with child annoyance. These findings illustrate the complex relationships between our environment, how we may perceive it, social factors and health. Better understanding of these relationships will undoubtedly allow us to more effectively quantify the actual effect of noise on human health. PMID:27801858

  13. Low noise road surfaces

    OpenAIRE

    Bolčina, Matjaž

    2014-01-01

    Noise is everywhere. Noise is a sound that makes people stressful and irritate. It often couses sleep disorders and also health problems like different cardiovascular disorders, hearing loss…In most cases traffic noise is the most disturbing. There are different ways to prevent people from traffic noise like building noise barriers and insulation of facades. However noise barriers and insulation of facades do not prevent noise formation, but are lowering existing noise. Another disadvantage i...

  14. Water Resources Vulnerability Assessment Accounting for Human Influence

    Science.gov (United States)

    Mehran, A.; AghaKouchak, A.

    2014-12-01

    Reservoirs are one of the main infrastructures that provide resilience against extremes (e.g., floods and droughts) and they play a key role in water resources management. Based on International Commission of Large Dams (ICOLD 2003) records, the total volume of reservoirs is over 6200 km3, which is twice larger than the global annual water use estimated as 3000 km3. Just a simple comparison of the two numbers indicates the importance of reservoirs and their role in providing resilience for water security. On the other hand, man-made reservoirs change the water distribution throughout the year. Most climate change impact studies ignore the role of reservoirs in water availability studies. However, water availability cannot be properly assessed without a thorough assessment of reservoir conditions. By combining classical methods for climate variability assessment (top-down approach) and influence assessment (bottom-up approach), this study offers a hybrid framework that integrates different drivers of water storage vulnerability. Final index is termed as the Multivariate Standardized Reliability and Resilience Index (MSRRI). This index investigates the adaptive capacity of the reservoir and exposure of the system to variable conditions. MSRRI has been investigated over several major reservoirs in Australia and California, United States. This presentation reviews recent findings and discusses reservoir conditions in Australia and California using MSRRI under different climatic change scenarios.

  15. Speech production in amplitude-modulated noise

    DEFF Research Database (Denmark)

    Macdonald, Ewen N; Raufer, Stefan

    2013-01-01

    The Lombard effect refers to the phenomenon where talkers automatically increase their level of speech in a noisy environment. While many studies have characterized how the Lombard effect influences different measures of speech production (e.g., F0, spectral tilt, etc.), few have investigated...... the consequences of temporally fluctuating noise. In the present study, 20 talkers produced speech in a variety of noise conditions, including both steady-state and amplitude-modulated white noise. While listening to noise over headphones, talkers produced randomly generated five word sentences. Similar...... to previous studies, talkers raised the level of their voice in steady-state noise. While talkers also increased the level of their voice in amplitude-modulated noise, the increase was not as large as that observed in steady-state noise. Importantly, for the 2 and 4 Hz amplitude-modulated noise conditions...

  16. Low-arousal speech noise improves performance in N-back task: an ERP study.

    Directory of Open Access Journals (Sweden)

    Longzhu Han

    Full Text Available The relationship between noise and human performance is a crucial topic in ergonomic research. However, the brain dynamics of the emotional arousal effects of background noises are still unclear. The current study employed meaningless speech noises in the n-back working memory task to explore the changes of event-related potentials (ERPs elicited by the noises with low arousal level vs. high arousal level. We found that the memory performance in low arousal condition were improved compared with the silent and the high arousal conditions; participants responded more quickly and had larger P2 and P3 amplitudes in low arousal condition while the performance and ERP components showed no significant difference between high arousal and silent conditions. These findings suggested that the emotional arousal dimension of background noises had a significant influence on human working memory performance, and that this effect was independent of the acoustic characteristics of noises (e.g., intensity and the meaning of speech materials. The current findings improve our understanding of background noise effects on human performance and lay the ground for the investigation of patients with attention deficits.

  17. Restriction of shot noise and material noise in a multilevel photochromic memory on signal-to-noise ratio

    Institute of Scientific and Technical Information of China (English)

    Zhang Qi-Cheng; Ni Yi; Xu Duan-Yi; Hu Heng

    2006-01-01

    The recording density of multilevel photochromic memory is limited by the signal-to-noise ratio (SNR) of the readout signal. In this paper, shot noise and material noise are investigated through theoretical analysis of SNR. When the bandwidth of a system is less than 1MHz, the material noise takes a prominent position; when the bandwidth of the system is more than 10MHz, the shot noise becomes dominant. The thickness of recording layer can be optimized to maximize the SNR and reduce the influence of the bandwidth of the system on SNR.

  18. Hand classification of fMRI ICA noise components.

    Science.gov (United States)

    Griffanti, Ludovica; Douaud, Gwenaëlle; Bijsterbosch, Janine; Evangelisti, Stefania; Alfaro-Almagro, Fidel; Glasser, Matthew F; Duff, Eugene P; Fitzgibbon, Sean; Westphal, Robert; Carone, Davide; Beckmann, Christian F; Smith, Stephen M

    2016-12-16

    We present a practical "how-to" guide to help determine whether single-subject fMRI independent components (ICs) characterise structured noise or not. Manual identification of signal and noise after ICA decomposition is required for efficient data denoising: to train supervised algorithms, to check the results of unsupervised ones or to manually clean the data. In this paper we describe the main spatial and temporal features of ICs and provide general guidelines on how to evaluate these. Examples of signal and noise components are provided from a wide range of datasets (3T data, including examples from the UK Biobank and the Human Connectome Project, and 7T data), together with practical guidelines for their identification. Finally, we discuss how the data quality, data type and preprocessing can influence the characteristics of the ICs and present examples of particularly challenging datasets.

  19. Effects of Quantum Noise on Quantum Clock Synchronization

    Institute of Scientific and Technical Information of China (English)

    谢端; 彭进业

    2012-01-01

    In laboratory environment, the channel apparatus will generate particular dominant quantum noise. The noise then will give rise to some errors during synchronization. In this work, the accuracies of one qubit transport protocol and entangled states transport protocol in the presence of noise have been studied. With the help of three important and familiar noise models, the quantum noise will degrade the accuracy has been proved. Due to the influence of quantum noise, the accuracy of entangled qubits decrease faster than that of one qubit. The entangled states will improve the accuracy in noise-free channel, and will degrade the accuracy in noise channel.

  20. Influence of heredity on human sensitivity to environmental chemicals

    Energy Technology Data Exchange (ETDEWEB)

    Weber, W.W. [Univ. of Michigan, Ann Arbor, MI (United States)

    1995-12-31

    Hereditary peculiarities in individual responses to environmental chemicals are a common occurrence in human populations. Genetic variation in glutathione S-transferase, CYP1A2, N-acetyltransferase, and paraoxonase exemplify the relationship of metabolic variation to individual susceptibility to cancer and other toxicants of environmental origin. Heritable receptor protein variants, a subset of proteins of enormous pharmacogenetic, potential that have not thus far been extensively explored form the pharmacogenetic standpoint, and also considered. Examples of interest that are considered include receptor variants associated with retinoic acid resistance in acute promyelocytic leukemia, with paradoxical responses to antiandrogens in prostate cancer, and with retinitis pigmentosa. Additional heritable protein variants of pharmacogenetic interest that result in antibiotic-induced deafness, glucocorticoid-remediable aldosteronism and hypertension, the long-QT syndrome, and beryllium-induced lung disease are also discussed. These traits demonstrate how knowledge of the molecular basis and mechanism of the variant response may contribute to its prevention in sensitive persons as well as to improved therapy for genetically conditioned disorders that arise form environmental chemicals. 99 refs.

  1. The Influence of Human Body Orientation on Distance Judgments

    Directory of Open Access Journals (Sweden)

    Edgard eJung

    2016-03-01

    Full Text Available People maintain larger distances to other peoples’ front than to their back. We investigated if humans also judge another person as closer when viewing their front than their back. Participants watched animated virtual characters (avatars and moved a virtual plane towards their location after the avatar was removed. In Experiment 1, participants judged avatars, which were facing them as closer and made quicker estimates than to avatars looking away. In Experiment 2, avatars were rotated in 30 degree steps around the vertical axis. Observers judged avatars roughly facing them (i.e., looking max. 60 degrees away as closer than avatars roughly looking away. No particular effect was observed for avatars directly facing and also gazing at the observer. We conclude that body orientation was sufficient to generate the asymmetry. Sensitivity of the orientation effect to gaze and to interpersonal distance would have suggested involvement of social processing, but this was not observed. We discuss social and lower-level processing as potential reasons for the effect.

  2. Hot spices influence permeability of human intestinal epithelial monolayers.

    Science.gov (United States)

    Jensen-Jarolim, E; Gajdzik, L; Haberl, I; Kraft, D; Scheiner, O; Graf, J

    1998-03-01

    Indirect evidence suggests that hot spices may interact with epithelial cells of the gastrointestinal tract to modulate their transport properties. Using HCT-8 cells, a cell line from a human ileocoecal carcinoma, we studied the effects of spices on transepithelial electrical resistance (TER), permeability for fluorescein isothiocyanate (FITC)-labeled dextrans with graded molecular weight, and morphological alterations of tight junctions by immunofluorescence using an anti-ZO-1 antibody, a marker for tight junction integrity. Two different reactivity patterns were observed: paprika and cayenne pepper significantly decreased the TER and increased permeability for 10-, 20- and 40-kDa dextrans but not for -70 kDa dextrans. Simultaneously, tight junctions exhibited a discontinuous pattern. Applying extracts from black or green pepper, bay leaf or nutmeg increased the TER and macromolecular permeability remained low. Immunofluorescence ZO-1 staining was preserved. In accordance with the above findings, capsaicin transiently reduced resistance and piperine increased resistance, making them candidates for causing the effects seen with crude spice extracts. The observation that Solanaceae spices (paprika, cayenne pepper) increase permeability for ions and macromolecules might be of pathophysiological importance, particularly with respect to food allergy and intolerance.

  3. Influence of diabetes mellitus on immunity to human tuberculosis.

    Science.gov (United States)

    Kumar Nathella, Pavan; Babu, Subash

    2017-09-01

    Type 2 diabetes mellitus(DM) is a major risk factor for the development of active pulmonary tuberculosis (TB), with development of DM pandemic in countries where TB is also endemic. Understanding the impact of DM on TB and the determinants of co-morbidity is essential in responding to this growing public health problem with improved therapeutic approaches. Despite the clinical and public health significance posed by the dual burden of TB and DM, little is known about the immunological and biochemical mechanisms of susceptibility. One possible mechanism is that an impaired immune response in patients with DM facilitates either primary infection with Mycobacterium tuberculosis or reactivation of latent TB. Diabetes is associated with immune dysfunction and alterations in the components of the immune system, including altered levels of specific cytokines and chemokines. Some effects of DM on adaptive immunity that are potentially relevant to TB defence have been identified in humans. In this review, we summarize current findings regarding the alterations in the innate and adaptive immune responses and immunological mechanisms of susceptibility of patients with DM to M. tuberculosis infection and disease. © 2017 John Wiley & Sons Ltd.

  4. Influence of passive muscle tension on electromechanical delay in humans.

    Directory of Open Access Journals (Sweden)

    Lilian Lacourpaille

    Full Text Available BACKGROUND: Electromechanical delay is the time lag between onsets of muscle activation and muscle force production and reflects both electro-chemical processes and mechanical processes. The aims of the present study were two-fold: to experimentally determine the slack length of each head of the biceps brachii using elastography and to determine the influence of the length of biceps brachii on electromechanical delay and its electro-chemical/mechanical processes using very high frame rate ultrasound. METHODS/RESULTS: First, 12 participants performed two passive stretches to evaluate the change in passive tension for each head of the biceps brachii. Then, they underwent two electrically evoked contractions from 120 to 20° of elbow flexion (0°: full extension, with the echographic probe maintained over the muscle belly and the myotendinous junction of biceps brachii. The slack length was found to occur at 95.5 ± 6.3° and 95.3 ± 8.2° of the elbow joint angle for the long and short heads of the biceps brachii, respectively. The electromechanical delay was significantly longer at 120° (16.9 ± 3.1 ms; p0.95. CONCLUSION: In contrast to previous observations on gastrocnemius medialis, the onset of muscle motion and the onset of myotendinous junction motion occurred simultaneously regardless of the length of the biceps brachii. That suggests that the between-muscles differences reported in the literature cannot be explained by different muscle passive tension but instead may be attributable to muscle architectural differences.

  5. Influence of Artificial Sweetener on Human Blood Glucose Concentration

    Directory of Open Access Journals (Sweden)

    Ilse Skokan

    2007-01-01

    Full Text Available Artificial sweeteners, such as saccharin or cyclamic acid are synthetically manufactured sweetenings. Known for their low energetic value they serve especially diabetic and adipose patients as sugar substitutes. It has been hypothesized that the substitution of sugar with artificial sweeteners may induce a decrease of the blood glucose. The aim of this study was to determine the reliability of this hypothesis by comparing the influence of regular table sugar and artificial sweeteners on the blood glucose concentration. In this pilot-study 16 patients were included suffering from adiposity, pre-diabetes and hypertension. In the sense of a cross-over design, three test trials were performed at intervals of several weeks. Each trial was followed by a test free interval. Within one test trial each patient consumed 150 ml test solution (water that contained either 6 g of table sugar (“Kandisin” with sweetener free serving as control group. Tests were performed within 1 hr after lunch to ensure conditions comparable to patients having a desert. Every participant had to determine their blood glucose concentration immediately before and 5, 15, 30 and 60 minutes after the intake of the test solution. For statistics an analysis of variance was performed. The data showed no significant changes in the blood glucose concentration. Neither the application of sugar (F4;60 = 1.645; p = .175 nor the consumption of an artificial sweetener (F2.068;31.023 = 1.551; p > .05 caused significant fluctuations in the blood sugar levels. Over a time frame of 60 minutes in the control group a significant decrease of the blood sugar concentration was found (F2.457;36.849 = 4.005; p = .020 as a physiological reaction during lunch digestion.

  6. Influence of the Thickness of the Barrier Layer in Nanoheterostructures and the Gate-Drain Capacitance on the Microwave and Noise Parameters of Field-Effect AlGaN/GaN HEMT

    Science.gov (United States)

    Mikhaylovich, S. V.; Fedorov, Yu. V.

    2016-07-01

    We perform a computational and analytical study of how the thickness of the barrier layer in nanoheterostructures and the gate-drain capacitance C gd influence the microwave parameters (limiting frequency of current amplification and maximum generation frequency) and noise parameters (noise factor) of a field-effect AlGaN/GaN high electron mobility transistor. The results of complex measurements of the parameters of such transistors based on nanoheterostructures with a barrier layer thickness of 3.5-15.7 nm, which were performed within the framework of four technological routes in the range 0.1-67 GHz, are presented. It is shown that in order to reduce the noise ratio and improve the microwave parameters, it is necessary to optimize both the parameters of nanoheterostructures and the manufacturing techniques. In particular, the thickness of the barrier layer should be reduced, and the gate length should be chosen such as to maximize the product of the squared maximum current amplification frequency in the interior of the transistor and the output impedance between the drain and the source. Additionally, attention should be given to the shape of the gate to reduce the capacitance C gd. Under certain conditions of manufacture of nitride field-effect HEMT, one can achieve a lower noise factor compared with the transistors based on arsenide nanoheterostructures.

  7. Pharmacodynamic Profile of Tramadol in Humans: Influence of Naltrexone Pretreatment

    Science.gov (United States)

    Stoops, William W.; Lofwall, Michelle R.; Nuzzo, Paul A.; Craig, Lori B.; Siegel, Anthony J.; Walsh, Sharon L.

    2012-01-01

    Rationale Tramadol is a prescription analgesic that activates mu opioid and monoamine receptor systems. Tramadol is thought to have limited abuse potential compared to mu opioid agonists, but laboratory data indicate that it shares some of their pharmacodynamic effects. Objectives This study evaluated the effect of mu opioid receptor blockade with naltrexone on the pharmacodynamic action of tramadol in humans. Methods This inpatient, double-blind, randomized, within-subject study examined the effects of oral placebo, tramadol (87.5, 175 and 350 mg) and hydromorphone (4 and 16 mg; positive control) after 1 hr pretreatment with oral naltrexone (0 and 50 mg). Ten recreational opioid users completed the study. Pharmacodynamic effects were measured before and for 7 hr after initial drug administration. Results Lower doses of tramadol and hydromorphone were generally placebo-like. Hydromorphone (16 mg) produced prototypic mu opioid agonist-like effects that were blocked by naltrexone. Tramadol (350 mg) produced miosis and increased ratings of “Good Effects” and “Liking ,” but also increased ratings of “Bad Effects.” Naltrexone reversed tramadol-induced physiological effects and mydriasis emerged, but unlike results with hydromorphone, naltrexone only partially attenuated tramadol’s positive subjective effects and actually enhanced several unpleasant subjective ratings. Conclusions Naltrexone can be used to disentangle the mixed neuropharmacological actions of tramadol. High dose tramadol produces a mixed profile of effects. These data suggest that both mu and non-mu opioid actions play a role in tramadol’s subjective profile of action. PMID:22623016

  8. Mapping Urban Environmental Noise Using Smartphones

    Directory of Open Access Journals (Sweden)

    Jinbo Zuo

    2016-10-01

    Full Text Available Noise mapping is an effective method of visualizing and accessing noise pollution. In this paper, a noise-mapping method based on smartphones to effectively and easily measure environmental noise is proposed. By using this method, a noise map of an entire area can be created using limited measurement data. To achieve the measurement with certain precision, a set of methods was designed to calibrate the smartphones. Measuring noise with mobile phones is different from the traditional static observations. The users may be moving at any time. Therefore, a method of attaching an additional microphone with a windscreen is proposed to reduce the wind effect. However, covering an entire area is impossible. Therefore, an interpolation method is needed to achieve full coverage of the area. To reduce the influence of spatial heterogeneity and improve the precision of noise mapping, a region-based noise-mapping method is proposed in this paper, which is based on the distribution of noise in different region types tagged by volunteers, to interpolate and combine them to create a noise map. To validate the effect of the method, a comparison of the interpolation results was made to analyse our method and the ordinary Kriging method. The result shows that our method is more accurate in reflecting the local distribution of noise and has better interpolation precision. We believe that the proposed noise-mapping method is a feasible and low-cost noise-mapping solution.

  9. Temporal characteristics of the influence of punishment on perceptual decision making in the human brain

    OpenAIRE

    Blank, H.; Guido, B.; Heekeren, H.R.; Philiastides, M.G.

    2013-01-01

    Perceptual decision making is the process by which information from sensory systems is combined and used to influence our behavior. In addition to the sensory input, this process can be affected by other factors, such as reward and punishment for correct and incorrect responses. To investigate the temporal dynamics of how monetary punishment influences perceptual decision making in humans, we collected electroencephalography (EEG) data during a perceptual categorization task whereby the punis...

  10. Tandem Cylinder Noise Predictions

    Science.gov (United States)

    Lockhard, David P.; Khorrami, Mehdi R.; CHoudhari, Meelan M.; Hutcheson, Florence V.; Brooks, Thomas F.; Stead, Daniel J.

    2007-01-01

    In an effort to better understand landing-gear noise sources, we have been examining a simplified configuration that still maintains some of the salient features of landing-gear flow fields. In particular, tandem cylinders have been studied because they model a variety of component level interactions. The present effort is directed at the case of two identical cylinders spatially separated in the streamwise direction by 3.7 diameters. Experimental measurements from the Basic Aerodynamic Research Tunnel (BART) and Quiet Flow Facility (QFF) at NASA Langley Research Center (LaRC) have provided steady surface pressures, detailed off-surface measurements of the flow field using Particle Image Velocimetry (PIV), hot-wire measurements in the wake of the rear cylinder, unsteady surface pressure data, and the radiated noise. The experiments were conducted at a Reynolds number of 166 105 based on the cylinder diameter. A trip was used on the upstream cylinder to insure a fully turbulent shedding process and simulate the effects of a high Reynolds number flow. The parallel computational effort uses the three-dimensional Navier-Stokes solver CFL3D with a hybrid, zonal turbulence model that turns off the turbulence production term everywhere except in a narrow ring surrounding solid surfaces. The current calculations further explore the influence of the grid resolution and spanwise extent on the flow and associated radiated noise. Extensive comparisons with the experimental data are used to assess the ability of the computations to simulate the details of the flow. The results show that the pressure fluctuations on the upstream cylinder, caused by vortex shedding, are smaller than those generated on the downstream cylinder by wake interaction. Consequently, the downstream cylinder dominates the noise radiation, producing an overall directivity pattern that is similar to that of an isolated cylinder. Only calculations based on the full length of the model span were able to

  11. Influence of horse stable environment on human airways

    Directory of Open Access Journals (Sweden)

    Pringle John

    2009-05-01

    Full Text Available Abstract Background Many people spend considerable amount of time each day in equine stable environments either as employees in the care and training of horses or in leisure activity. However, there are few studies available on how the stable environment affects human airways. This study examined in one horse stable qualitative differences in indoor air during winter and late summer conditions and assessed whether air quality was associated with clinically detectable respiratory signs or alterations to selected biomarkers of inflammation and lung function in stable personnel. Methods The horse stable environment and stable-workers (n = 13 in one stable were investigated three times; first in the winter, second in the interjacent late summer and the third time in the following winter stabling period. The stable measurements included levels of ammonia, hydrogen sulphide, total and respirable dust, airborne horse allergen, microorganisms, endotoxin and glucan. The stable-workers completed a questionnaire on respiratory symptoms, underwent nasal lavage with subsequent analysis of inflammation markers, and performed repeated measurements of pulmonary function. Results Measurements in the horse stable showed low organic dust levels and high horse allergen levels. Increased viable level of fungi in the air indicated a growing source in the stable. Air particle load as well as 1,3-β-glucan was higher at the two winter time-points, whereas endotoxin levels were higher at the summer time-point. Two stable-workers showed signs of bronchial obstruction with increased PEF-variability, increased inflammation biomarkers relating to reported allergy, cold or smoking and reported partly work-related symptoms. Furthermore, two other stable-workers reported work-related airway symptoms, of which one had doctor's diagnosed asthma which was well treated. Conclusion Biomarkers involved in the development of airway diseases have been studied in relation to

  12. [The concept of medical entomology: the management of the influence of arthropods on human health].

    Science.gov (United States)

    Rasnitsyn, S P

    1997-01-01

    The tasks of medical entomology are analyzed with special reference to the development of methods of protection against the harmful influence of arthropods on human health and the use of these animals in health sciences. Special attention is paid to the following problems: characterization of individual and group features of humans and their relationship with arthropods, elucidation of the properties of arthropods, determination of the state of their populations, estimation of the efficiency of controlling measures, their ecological consequences, etc.

  13. Study of an investigation on factors influencing human resources productivity in Shiraz University of Medical Sciences

    Directory of Open Access Journals (Sweden)

    Zahra Ghasemi

    2016-01-01

    Full Text Available Introduction: Human resources development is one of the most important components of any organization and detecting important factors influencing human resources management plays an essential role in the success of the firms. In this study, we investigated different factors influencing human resources productivity of Shiraz University of Medical Sciences staff. Method: The present research was a cross-sectional study. Sample size was calculated 208 individuals. To access information about the human resource productivity, a valid and reliable questionnaire was used. The data were analyzed using SPSS software. Pearson correlation was used for statistical analysis of the data (p=0.05. Results:The results showed that there was a statistically significant relationship (p-value<0.001 between human resources productivity and factors affecting the productivity of human resources (motivational factors, leadership style, creativity and innovation, general and applied education, and competitive spirit. Motivational factors (r =0.89 and general education (r =0.65 had the most and the least effects on human resources productivity. Conclusion: Considering the fact that motivational factors were the most effective factors on human resource productivity, we recommend that managers should care more than before about this factor; also, in order to motivate the employees, they should consider the staff’s individual differences.

  14. A Phase Noise Analysis Method for Millimeter-Wave Passive Imager BHU-2D-U Frequency Synthesizer

    OpenAIRE

    Jin Zhang; Cheng Zheng; Xianxun Yao; Baohua Yang

    2013-01-01

    A nontrivial phase noise analysis method is proposed for frequency synthesizer of a passive millimeter-wave synthetic aperture interferometric radiometer (SAIR) imager for concealed weapon detections on human bodies with high imaging rates. The frequency synthesizer provides local oscillator signals for both millimeter-wave front ends and intermediate frequency IQ demodulators for the SAIR system. The influence of synthesizer phase noise in different offset frequency ranges on the visibility ...

  15. Influence of biofuels on exhaust gas and noise emissions of small industrial diesel engines; Einfluss von Biokraftstoffen auf die Abgas- und Geraeuschemission kleiner Industriedieselmotoren

    Energy Technology Data Exchange (ETDEWEB)

    Spessert, B.M. [Fachhochschule Jena (Germany). Fachgebiet Kraft- und Arbeitsmaschinen; Schleicher, A. [Fachhochschule Jena (Germany). Fachgebiet Umweltmesstechnik

    2007-03-15

    At small industrial diesel engines, as they were brought in oftentimes on building sites, in the farming and forest industry and on boats, biofuels are increasingly used. In a research project of the University of Applied Sciences Jena, Germany, thus the changes of the exhaust gas pollutant and noise emissions of these diesel engines were investigated. Test fuels were diesel fuel, and also biofuels as biodiesel (RME), rape seed oil and sun flower oil. Depending on the operating point these biofuels increased or reduced the emissions of exhaust gas and noise of the investigated engines clearly. (orig.)

  16. Geomagnetic Storms and their Influence on the Human Brain Functional State

    Directory of Open Access Journals (Sweden)

    Elchin S. Babayev

    2005-01-01

    Full Text Available An investigation of the influence of geomagnetic storms of various intensities on healthy adults' human brain activity and its functional state was conducted. Results of electroencephalogram (EEG investigations were used as the most objective method reflecting functional state of the human brain. Studies on the influence of geomagnetic storms on the human brain functional state of healthy adult women patients (permanent group in states of relaxation, photo-stimulation and hyper-ventilation have revealed a negative influence of severe geomagnetic storms on functional state of the human brain. As a rule, during periods of strong geomagnetic disturbances, indisposition, weakness and presence of indistinct localized headaches were recorded for majority of patients. Complex of nonspecific shifts on EEG reflects disorganization of functional activity of cortex of large hemispheres of the human brain at geomagnetically disturbed days, which is likely connected with dysfunction of integrative subcortical systems, with disbalance of its ascending synchronizing and desynchronizing influences. Imbalance of activating and deactivating mechanisms including dysfunctions of ergo- and tropho-tropic over-segmentary centers was registered. Strengthening cortical connections in the right cortical hemisphere and their short circuit on temporal sections during geomagnetically disturbed days were observed, while, in geomagnetically quiet days, a profile of correlation interrelations reflected weak internal- and inter-hemispheric connections. The threshold of convulsive (spasmodic readiness of the human brain is reduced, which is especially dangerous for risk group persons. It is established that, in general, weak and moderate geomagnetic storms exert stimulating influence while strong disturbances of geomagnetic conditions activate braking (inhibiting processes.

  17. Pavement noise measurements in Poland

    Science.gov (United States)

    Zofka, Ewa; Zofka, Adam; Mechowski, Tomasz

    2017-09-01

    The objective of this study is to investigate the feasibility of the On-Board Sound Intensity (OBSI) system to measure tire-pavement noise in Poland. In general, sources of noise emitted by the modern vehicles are the propulsion noise, aerodynamic resistance and noise generated at the tire-pavement interface. In order to capture tire-pavement noise, the OBSI system uses a noise intensity probe installed in the close proximity of that interface. In this study, OBSI measurements were performed at different types of pavement surfaces such as stone mastic asphalt (SMA), regular asphalt concrete (HMA) as well as Portland cement concrete (PCC). The influence of several necessary OBSI measurement conditions were recognized as: testing speed, air temperature, tire pressure and tire type. The results of this study demonstrate that the OBSI system is a viable and robust tool that can be used for the quality evaluation of newly built asphalt pavements in Poland. It can be also applied to generate reliable input parameters for the noise propagation models that are used to assess the environmental impact of new and existing highway corridors.

  18. Early life influences on cognition, behavior, and emotion in humans: from birth to age 20

    NARCIS (Netherlands)

    Bergh, B.R. Van den; Loomans, E.M.; Mennes, M.

    2015-01-01

    The long-lasting effects of fetal exposure to early life influences (ELI) such as maternal anxiety, stress, and micronutrient deficiencies as well as mediating and moderating factors are quite well established in animal studies, but remain unclear in humans. Here, we report about effects on cognitio

  19. The sedimentary dynamics in natural and human-influenced delta channel belts

    NARCIS (Netherlands)

    Hobo, N.

    2015-01-01

    This study investigates the increased anthropogenic influence on the within-channel belt sedimentary dynamics in the Rhine delta. To make this investigation, the sedimentary dynamics within the life-cycle of a single channel belt were reconstructed for three key periods of increasing human impact, w

  20. Genetic and environmental influences on adult human height across birth cohorts from 1886 to 1994

    DEFF Research Database (Denmark)

    Jelenkovic, Aline; Hur, Yoon-Mi; Sund, Reijo

    2016-01-01

    Human height variation is determined by genetic and environmental factors, but it remains unclear whether their influences differ across birth-year cohorts. We conducted an individual-based pooled analysis of 40 twin cohorts including 143,390 complete twin pairs born 1886–1994. Although genetic v...

  1. Past Experience Influences the Processing of Stimulus Compounds in Human Pavlovian Conditioning

    Science.gov (United States)

    Melchers, Klaus G.; Lachnit, Harold; Shanks, David R.

    2004-01-01

    In two human skin conductance conditioning experiments we investigated whether processing of stimulus compounds can be influenced by past experience. Participants were either pre-trained with a discrimination problem that could be solved elementally (A+, B-, AB+, C- in Experiment 1 and A+, AB+, C-, CB- in Experiment 2) or one that required a…

  2. Analysis of Factors Influencing Undergraduates' Occupation Choices: An Investigation of Both Social and Human Capital

    Science.gov (United States)

    Liming, Li; Shunguo, Zhang

    2015-01-01

    Based on 2006 survey data on students from three universities in western China, this study analyzes the effect of the students' family background and academic achievements on their occupation choices. Both social capital and human capital were found to be significant factors influencing their employment decisions. The more abundant the social and…

  3. Climate suitability and human influences combined explain the range expansion of an invasive horticultural plant

    Science.gov (United States)

    Carolyn M. Beans; Francis F. Kilkenny; Laura F. Galloway

    2012-01-01

    Ecological niche models are commonly used to identify regions at risk of species invasions. Relying on climate alone may limit a model's success when additional variables contribute to invasion. While a climate-based model may predict the future spread of an invasive plant, we hypothesized that a model that combined climate with human influences would most...

  4. Influence of a nanoporous zirconia implant surface of on cell viability of human osteoblasts

    NARCIS (Netherlands)

    Aboushelib, M.N.; Osman, E.; Jansen, I.; Everts, V.; Feilzer, A.J.

    2013-01-01

    Purpose: The dense nonretentive surface of zirconia implants was modified into a nanoporous surface using selective infiltration etching surface treatment. The aim of this study was to investigate the influence of such a nanoporous modified zirconia surface on the attachment of human osteoblasts.

  5. Discussion on the Influence of Cultural Traditions To wards the Development of Human Rights

    Institute of Scientific and Technical Information of China (English)

    HUO GUIHUAN

    2011-01-01

    No matter whether we consider it from the perspective of historical development or specific conditions of reality,the formation of the concept of human rights,especially its process of playing the realistic role via the concrete realization,has a direct and extremely close relationship with specific cultural values and historical heritages.Therefore,studies of human rights should not just remain at the abstract level of "from concept to concept." On the contrary,we should further promote the sound development of the cause of human rights via concretizing this kind of studies.Consequently,revealing the influence of cultural traditions towards the development of human rights by exploring and studying the relationship betveen the concepts of human rights and cultural traditions has great practical significance and valuable intellectual merits.

  6. Human disturbance influences reproductive success and growth rate in California sea lions (Zalophus californianus).

    Science.gov (United States)

    French, Susannah S; González-Suárez, Manuela; Young, Julie K; Durham, Susan; Gerber, Leah R

    2011-03-16

    The environment is currently undergoing changes at both global (e.g., climate change) and local (e.g., tourism, pollution, habitat modification) scales that have the capacity to affect the viability of animal and plant populations. Many of these changes, such as human disturbance, have an anthropogenic origin and therefore may be mitigated by management action. To do so requires an understanding of the impact of human activities and changing environmental conditions on population dynamics. We investigated the influence of human activity on important life history parameters (reproductive rate, and body condition, and growth rate of neonate pups) for California sea lions (Zalophus californianus) in the Gulf of California, Mexico. Increased human presence was associated with lower reproductive rates, which translated into reduced long-term population growth rates and suggested that human activities are a disturbance that could lead to population declines. We also observed higher body growth rates in pups with increased exposure to humans. Increased growth rates in pups may reflect a density dependent response to declining reproductive rates (e.g., decreased competition for resources). Our results highlight the potentially complex changes in life history parameters that may result from human disturbance, and their implication for population dynamics. We recommend careful monitoring of human activities in the Gulf of California and emphasize the importance of management strategies that explicitly consider the potential impact of human activities such as ecotourism on vertebrate populations.

  7. Human disturbance influences reproductive success and growth rate in California sea lions (Zalophus californianus.

    Directory of Open Access Journals (Sweden)

    Susannah S French

    Full Text Available The environment is currently undergoing changes at both global (e.g., climate change and local (e.g., tourism, pollution, habitat modification scales that have the capacity to affect the viability of animal and plant populations. Many of these changes, such as human disturbance, have an anthropogenic origin and therefore may be mitigated by management action. To do so requires an understanding of the impact of human activities and changing environmental conditions on population dynamics. We investigated the influence of human activity on important life history parameters (reproductive rate, and body condition, and growth rate of neonate pups for California sea lions (Zalophus californianus in the Gulf of California, Mexico. Increased human presence was associated with lower reproductive rates, which translated into reduced long-term population growth rates and suggested that human activities are a disturbance that could lead to population declines. We also observed higher body growth rates in pups with increased exposure to humans. Increased growth rates in pups may reflect a density dependent response to declining reproductive rates (e.g., decreased competition for resources. Our results highlight the potentially complex changes in life history parameters that may result from human disturbance, and their implication for population dynamics. We recommend careful monitoring of human activities in the Gulf of California and emphasize the importance of management strategies that explicitly consider the potential impact of human activities such as ecotourism on vertebrate populations.

  8. Using noise to shape motor learning.

    Science.gov (United States)

    Thorp, Elias B; Kording, Konrad P; Mussa-Ivaldi, Ferdinando A

    2017-02-01

    Each of our movements is selected from any number of alternative movements. Some studies have shown evidence that the central nervous system (CNS) chooses to make the specific movements that are least affected by motor noise. Previous results showing that the CNS has a natural tendency to minimize the effects of noise make the direct prediction that if the relationship between movements and noise were to change, the specific movements people learn to make would also change in a predictable manner. Indeed, this has been shown for well-practiced movements such as reaching. Here, we artificially manipulated the relationship between movements and visuomotor noise by adding noise to a motor task in a novel redundant geometry such that there arose a single control policy that minimized the noise. This allowed us to see whether, for a novel motor task, people could learn the specific control policy that minimized noise or would need to employ other compensation strategies to overcome the added noise. As predicted, subjects were able to learn movements that were biased toward the specific ones that minimized the noise, suggesting not only that the CNS can learn to minimize the effects of noise in a novel motor task but also that artificial visuomotor noise can be a useful tool for teaching people to make specific movements. Using noise as a teaching signal promises to be useful for rehabilitative therapies and movement training with human-machine interfaces.

  9. Noise gates for decoherent quantum circuits

    OpenAIRE

    Bassi, Angelo; Deckert, D. -A.

    2008-01-01

    A major problem in exploiting microscopic systems for developing a new technology based on the principles of Quantum Information is the influence of noise which tends to work against the quantum features of such systems. It becomes then crucial to understand how noise affects the evolution of quantum circuits: several techniques have been proposed among which stochastic differential equations (SDEs) can represent a very convenient tool. We show how SDEs naturally map any Markovian noise into ...

  10. Combined Annoyance Assessment of Subway Train-Induced Structural Vibration and Ambient Noise

    Directory of Open Access Journals (Sweden)

    Ke Sun

    2016-01-01

    Full Text Available The subway train-induced structural vibration and ambient noise may cause annoyance and other negative influences on the human body. Presently, limited models have been developed to execute the quantitative evaluation of the combined annoyance caused by both structural vibration and ambient noise. In this study, a fuzzy membership function and normal distribution function were coupled to describe the fuzziness and randomness of human annoyance responses; a novel annoyance evaluation model was proposed to assess the structural vibration and ambient noise; and the annoyance of human was classified into six grades. Subsequently, we integrated an actual case into this study to calculate and analyze the combined annoyance degree. The applied results were compared with the standard limits, in which the rationality and superiority of the proposed model were verified. The results exhibit the notion that the proposed models perform well and can serve as a reference for spatial planning and development in the nearby subway environment.

  11. Stochastic noise in splicing machinery

    OpenAIRE

    Melamud, Eugene; Moult, John

    2009-01-01

    The number of known alternative human isoforms has been increasing steadily with the amount of available transcription data. To date, over 100 000 isoforms have been detected in EST libraries, and at least 75% of human genes have at least one alternative isoform. In this paper, we propose that most alternative splicing events are the result of noise in the splicing process. We show that the number of isoforms and their abundance can be predicted by a simple stochastic noise model that takes i...

  12. Inhibitory noise

    Directory of Open Access Journals (Sweden)

    Alain Destexhe

    2010-03-01

    Full Text Available Cortical neurons in vivo may operate in high-conductance states, in which the major part of the neuron's input conductance is due to synaptic activity, sometimes several-fold larger than the resting conductance. We examine here the contribution of inhibition in such high-conductance states. At the level of the absolute conductance values, several studies have shown that cortical neurons in vivo are characterized by strong inhibitory conductances. However, conductances are balanced and spiking activity is mostly determined by fluctuations, but not much is known about excitatory and inhibitory contributions to these fluctuations. Models and dynamic-clamp experiments show that, during high-conductance states, spikes are mainly determined by fluctuations of inhibition, or by inhibitory noise. This stands in contrast to low-conductance states, in which excitatory conductances determine spiking activity. To determine these contributions from experimental data, maximum likelihood methods can be designed and applied to intracellular recordings in vivo. Such methods indicate that action potentials are indeed mostly correlated with inhibitory fluctuations in awake animals. These results argue for a determinant role for inhibitory fluctuations in evoking spikes, and do not support feed-forward modes of processing, for which opposite patterns are predicted.

  13. Occupational noise management

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-06-15

    Occupational noise is a frequently encountered on-the-job health hazard. This guide presented the responsibilities and regulatory requirements related to business activities where noise above 80 decibels is present. The guide provided a definition of noise and discussed noise hazards, types of noise, and on-the-job noise exposure. A risk assessment to noise in the work environment was also discussed. A guide to a hearing conservation program was also included. The main purpose of a hearing conservation program is the prevention of noise induced hearing loss for employees exposed to occupational noise. The components of such a program were outlined, with particular reference to noise monitoring; noise exposure control; worker education and training; hearing (audiometric) testing; and annual program review and record keeping. It was concluded that in terms of record keeping, it can be very helpful to file noise exposure assessments, particularly personal exposure measurements, with hearing test records to facilitate for future reference. refs., appendices.

  14. Noise and Hearing Protection

    Science.gov (United States)

    ... ENTCareers Marketplace Find an ENT Doctor Near You Noise and Hearing Protection Noise and Hearing Protection Patient ... it is. How can I tell if a noise is dangerous? People differ in their sensitivity to ...

  15. Cosmological flux noise and measured noise power spectra in SQUIDs

    Science.gov (United States)

    Beck, Christian

    2016-06-01

    The understanding of the origin of 1/f magnetic flux noise commonly observed in superconducting devices such as SQUIDs and qubits is still a major unsolved puzzle. Here we discuss the possibility that a significant part of the observed low-frequency flux noise measured in these devices is ultimately seeded by cosmological fluctuations. We consider a theory where a primordial flux noise field left over in unchanged form from an early inflationary or quantum gravity epoch of the universe intrinsically influences the phase difference in SQUIDs and qubits. The perturbation seeds generated by this field can explain in a quantitatively correct way the form and amplitude of measured low-frequency flux noise spectra in SQUID devices if one takes as a source of fluctuations the primordial power spectrum of curvature fluctuations as measured by the Planck collaboration. Our theoretical predictions are in excellent agreement with recent low-frequency flux noise measurements of various experimental groups. Magnetic flux noise, so far mainly considered as a nuisance for electronic devices, may thus contain valuable information about fluctuation spectra in the very early universe.

  16. Influence of shape change of impeller and scroll in the axial direction on performance and noise for multiblade blower; Tayoku sofuki no haneguruma oyobi scroll keijo no jiku hoko henka ga seino to soon ni oyobosu eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Yanazaki, S.; Hashimoto, K.; Fukasaku, Y. [Hitachi, Ltd., Tokyo (Japan)

    1997-10-25

    In this paper, the influence of shape change of the impeller and scroll in the axial direction on performance and noise are investigated. It is shown that a 14% increase in the hub-side diameter of the impeller over that of the shroud side leads to a 4% increase in the efficiency {eta}t, and a 2dB reduction in the specific sound level SLs. It is also shown that an increase in the diffusion angle of the hub side of the scroll to that of the shroud side raises the efficiency by 2%. 8 refs., 10 figs.

  17. Field study on the impact of nocturnal road traffic noise on sleep: the importance of in- and outdoor noise assessment, the bedroom location and nighttime noise disturbances.

    Science.gov (United States)

    Pirrera, Sandra; De Valck, Elke; Cluydts, Raymond

    2014-12-01

    The aim of this field study is to gain more insight into the way nocturnal road traffic noise impacts the sleep of inhabitants living in noisy regions, by taking into account several modifying variables. Participants were tested during five consecutive nights in their homes and comparisons between effective indoor and outdoor noise levels (LAeq, LAmax, number of noise events), sleep (actigraphy and sleep logs) and aspects of well-being (questionnaires) were made. Also, we investigated into what extent nocturnal noise exposure - objectively measured as well as perceived - directly relates to sleep outcomes and how the bedroom location influenced our measurements. We found that subjects living and sleeping in noisy regions correctly perceive their environment in terms of noise exposure and reported an overall discomfort due to traffic noise. In the evaluation of the objective noise levels, the inside noise levels did not follow the outside noise levels, though the different noise patterns could be described as characteristic for a noise and quiet environment. The impact on sleep, however, was only modest and we did not find any influence of noise intrusion on mood or pre-sleep arousal levels. Concerning the subjectively reported noise disturbances during the night, a clear relationship between noise and sleep outcomes could be established; with sleep onset latencies and judged sleep quality being particularly affected. The importance of inside and outside noise assessment as well as the use of multiple noise indicators in a home environment is further described. Additional emphasis is put on the determination of quiet control regions and the bedroom location, as this can alter noise levels and sleep outcomes. Also, including subjective noise evaluations during the night might not only provide crucial information on how participants experience the noise, but also allows for a more qualitative interpretation of the actual noise situation.

  18. Effects of noise on human health. Methodological analysis of the findings of three epidemiological studies; Gesundheitliche Auswirkungen von Laermbelastung. Methodische Betrachtungen zu den Ergebnissen dreier epidemiologischer Studien

    Energy Technology Data Exchange (ETDEWEB)

    Bellach, B. [Robert-Koch-Inst., Berlin (Germany). Bundesinstitut fuer Infektionskrankheiten und Nicht-Uebertragbare Krankheiten, Fachbereich 6; Dortschy, R. [Robert-Koch-Inst., Berlin (Germany). Bundesinstitut fuer Infektionskrankheiten und Nicht-Uebertragbare Krankheiten, Fachbereich 6; Mueller, D. [Robert-Koch-Inst., Berlin (Germany). Bundesinstitut fuer Infektionskrankheiten und Nicht-Uebertragbare Krankheiten, Fachbereich 6; Ziese, T. [Robert-Koch-Inst., Berlin (Germany). Bundesinstitut fuer Infektionskrankheiten und Nicht-Uebertragbare Krankheiten, Fachbereich 6

    1995-03-01

    Studies on noise impact necessitate extensive acoustic measurements to find out about the real noise level, owing to the fact that not only the real noise level but also the subjective feeling of `noise nuisances` may correlate with health disorders. In order to test this hypothesis, this investigation summarizes the results of complex risk assessment studies in consideration of questionnaires on noise levels from three large-scale studies of the former Institute of Social medicine and Epidemiology (now: Department 6 of the Robert-Koch Institute). (orig.) [Deutsch] Zur Feststellung der tatsaechlichen Laermbelaestigung sind umfangreiche und aufwendige akustische Messungen erforderlich. Es korreliert nicht nur die tatsaechliche Laermbelastung, sondern auch die subjektiv empfundene Laermbelaestigung, wie sie in Frageboegen erfasst werden kann, mit Gesundheitsstoerungen. Zur Ueberpruefung dieser Hypothese sind im vorliegenden Text die Ergebnisse von komplexen Risikobewertungen unter Einbeziehung von Fragebogenangaben zur Laermbelastung aus drei grossen Studien des ehemaligen Instituts fuer Sozialmedizin und Epidemiologie (jetzt Fachbereich 6 des Robert Koch-Instituts) zusammengefasst. (orig.)

  19. Noise hazard course

    CERN Multimedia

    2003-01-01

    A 1/2 day course to promote awareness of the risks incurred by noise at the work place and recommendations to settle them. Next course Wednesday 24th September 2003. Costs are covered by TIS, Jacques Coillard from Bureau Véritas will present the course. Registration is obligatory. For more information and to enrol on this course go to the safety section of Human Resources Training and Development web pages, or contact : Ana-Paula Bernardes/TIS-GS (71385) or e-mail Ana-Paula.Bernardes@cern.ch

  20. Noise hazard course

    CERN Multimedia

    2003-01-01

    A 1/2 day course to promote awareness of the risks incurred by noise at the work place and recommendations to settle them. Next course Wednesday 24th September 2003. Costs are covered by TIS, Jacques Coillard from Bureau Véritas will present the course. Registration is obligatory. For more information and to enrol on this course go to the safety section of Human Resources Training and Development web pages, or contact: Ana-Paula Bernardes/TIS-GS (71385) or e-mail Ana-Paula.Bernardes@cern.ch

  1. Removing the Influence of Shimmer in the Calculation of Harmonics-To-Noise Ratios Using Ensemble-Averages in Voice Signals

    Directory of Open Access Journals (Sweden)

    Carlos Ferrer

    2009-01-01

    Full Text Available Harmonics-to-noise ratios (HNRs are affected by general aperiodicity in voiced speech signals. To specifically reflect a signal-to-additive-noise ratio, the measurement should be insensitive to other periodicity perturbations, like jitter, shimmer, and waveform variability. The ensemble averaging technique is a time-domain method which has been gradually refined in terms of its sensitivity to jitter and waveform variability and required number of pulses. In this paper, shimmer is introduced in the model of the ensemble average, and a formula is derived which allows the reduction of shimmer effects in HNR calculation. The validity of the technique is evaluated using synthetically shimmered signals, and the prerequisites (glottal pulse positions and amplitudes are obtained by means of fully automated methods. The results demonstrate the feasibility and usefulness of the correction.

  2. Ground Attenuation of Railroad Noise

    DEFF Research Database (Denmark)

    Makarewicz, R.; Rasmussen, Karsten Bo; Kokowski, P.

    1996-01-01

    The influence of ground effect on railroad noise is described using the concept of the peak A-weighted sound exposure level, and A-weighted sound exposure level. The train is modelled by a continuous line of incoherent point sources that have a cosine directivity. The ground effect is included by...

  3. The influence of human resource management on improvement of business ethics

    Directory of Open Access Journals (Sweden)

    Radenko Maric

    2010-02-01

    Full Text Available In this paper the importance of practice of human resource management as of a significant driver of business ethics in companies has been considered. The basic premise of the paper is the fact that the company’s main source of unethical behaviour is situated in its people’s activities which further implies that many measures aimed to apply and improve business ethics belong to the domain of human resource management. Based on research results on a sample of 36 enterprises, the paper attempts to answer important questions as: what are the problems regarding business ethics facing human resource experts and to what extent the existing human resource management practices influence the application and improvement of business ethics in Serbian enterprises.

  4. Nonsense-Mediated RNA Decay Influences Human Embryonic Stem Cell Fate

    Directory of Open Access Journals (Sweden)

    Chih-Hong Lou

    2016-06-01

    Full Text Available Nonsense-mediated RNA decay (NMD is a highly conserved pathway that selectively degrades specific subsets of RNA transcripts. Here, we provide evidence that NMD regulates early human developmental cell fate. We found that NMD factors tend to be expressed at higher levels in human pluripotent cells than in differentiated cells, raising the possibility that NMD must be downregulated to permit differentiation. Loss- and gain-of-function experiments in human embryonic stem cells (hESCs demonstrated that, indeed, NMD downregulation is essential for efficient generation of definitive endoderm. RNA-seq analysis identified NMD target transcripts induced when NMD is suppressed in hESCs, including many encoding signaling components. This led us to test the role of TGF-β and BMP signaling, which we found NMD acts through to influence definitive endoderm versus mesoderm fate. Our results suggest that selective RNA decay is critical for specifying the developmental fate of specific human embryonic cell lineages.

  5. Sympathetic influence on cerebral blood flow and metabolism during exercise in humans

    DEFF Research Database (Denmark)

    Seifert, Thomas; Secher, Niels H

    2011-01-01

    This review focuses on the possibility that autonomic activity influences cerebral blood flow (CBF) and metabolism during exercise in humans. Apart from cerebral autoregulation, the arterial carbon dioxide tension, and neuronal activation, it may be that the autonomic nervous system influences CBF......, but increases during cycling exercise. The increase in CMRO(2) is unaffected by beta-adrenergic blockade even though CBF is reduced suggesting that cerebral oxygenation becomes critical and a limited cerebral mitochondrial oxygen tension may induce fatigue. Also, sympathetic activity may drive cerebral non...

  6. Test of the Influence of Using Mixed Methanol-gasoline Fuel on Engine Exhaust Noise%甲醇汽油对发动机排气噪声影响的试验

    Institute of Scientific and Technical Information of China (English)

    殷俊; 张冰蔚

    2015-01-01

    With an improved 1.5 VCT engine as the test platform, the influence of combusting methanol-gasoline flexible fuel on the engine exhaust noise was investigated. The result of full speed load character test shows that the exhaust noise of the engine at middle and high speed for using methanol-gasoline fuel is higher than that for using gasoline. The difference of the engine exhaust noise between them can reach the maximum value of 4.0 dB (A) at 6 000 r/min speed. The result of load character test at 4 500 r/min speed shows that the exhaust noise for using methanol-gasoline fuel will increase when the load reaches 32%of the maximum load of M0.%以一款经过改造后的1.5 VCT发动机为试验研究平台,研究燃用甲醇汽油灵活燃料对排气噪声特性的影响.外特性试验结果表明甲醇汽油在中、高转速时使排气噪声增大,其中6 000 r/min时最大增加4.0 dB(A);负荷特性(4 500 r/min)试验表明负荷达到M0最大负荷的32%以上时排气噪声也会增大.

  7. Interpersonal influence among public health leaders in the United States Department of Health and Human Services

    Directory of Open Access Journals (Sweden)

    Jenine K. Harris

    2012-02-01

    Full Text Available Background. In public health, interpersonal influence has been identified as an important factor in the spread of health information, and in understanding and changing health behaviors. However, little is known about influence in public health leadership. Influence is important in leadership settings, where public health professionals contribute to national policy and practice agendas. Drawing on social theory and recent advances in statistical network modeling, we examined influence in a network of tobacco control leaders at the United States Department of Health and Human Services (DHHS. Design and Methods. Fifty-four tobacco control leaders across all 11 agencies in the DHHS were identified; 49 (91% responded to a web-based survey. Participants were asked about communication with other tobacco control leaders, who influenced their work, and general job characteristics. Exponential random graph modeling was used to develop a network model of influence accounting for characteristics of individuals, their relationships, and global network structures. Results. Higher job ranks, more experience in tobacco control, and more time devoted to tobacco control each week increased the likelihood of influence nomination, as did more frequent communication between network members. Being in the same agency and working the same number of hours per week were positively associated with mutual influence nominations. Controlling for these characteristics, the network also exhibited patterns associated with influential clusters of network members. Conclusions. Findings from this unique study provide a perspective on influence within a government agency that both helps to understand decision-making and also can serve to inform organizational efforts that allow for more effective structuring of leadership.

  8. [Influence of human activities on groundwater environment based on coefficient variation method].

    Science.gov (United States)

    Zhao, Wei; Lin, Jian; Wang, Shu-Fang; Liu, Ji-Lai; Chen, Zhong-Rong; Kou, Wen-Jie

    2013-04-01

    Groundwater system in the plain area of Beijing can be divided into six subsystems. Due to the different hydrogeological conditions of the subsystems, the degrees to which human activities affect the subsystems are also diverse. In order to evaluate the influence of human activities on each subsystem, the first and second aquifer with relatively poor water quality were chosen to be the evaluating positions, based on the data of groundwater sampled in September, 2011. With respect to human activities affect index such as total hardness, TDS, sulfate and ammonium, variation coefficient methods were used to calculate the weight of each index. Then scores were obtained for each index with national standard as reference, and superposition calculations were used to gain comprehensive scores, finally the groundwater quality conditions were evaluated. Contrast analyses were used to evaluate the incidence of human activities with groundwater subsystems as evaluation unit and water quality partitions as evaluation factors. The results indicate that the influence of human activities on the first aquifer is greater than that of the second aquifer, the Yongding river groundwater subsystems and the Chaobai river groundwater subsystems are affected more than other groundwater subsystems.

  9. The Problems with "Noise Numbers" for Wind Farm Noise Assessment

    Science.gov (United States)

    Thorne, Bob

    2011-01-01

    Human perception responds primarily to sound character rather than sound level. Wind farms are unique sound sources and exhibit special audible and inaudible characteristics that can be described as modulating sound or as a tonal complex. Wind farm compliance measures based on a specified noise number alone will fail to address problems with noise…

  10. Influence of different types of trams on human perception of vibrations in buildings

    Directory of Open Access Journals (Sweden)

    Kowalska-Koczwara Alicja

    2017-01-01

    Full Text Available In an increasingly urbanized areas transport vibration source are closer and closer to the receiver which is a building. At the same time residents requirements for comfort in rooms are higher. In this paper influence of transport vibrations from various types of trams on human perception was tested and analysed. Measurements were made in Cracow on 11 buildings located near tramway. Human perception were investigated according to ISO and Polish standard. Basic RMS method and additional VDV method were applied because of high crest factor of recorded signal. Results of both methods were compared.

  11. Variation in macronutrients in human bank milk: influencing factors and implications for human milk banking

    DEFF Research Database (Denmark)

    Michaelsen, K F; Skafte, L; Badsberg, J H;

    1990-01-01

    Protein (P), fat (F), and carbohydrate (C) concentration in expressed human bank milk was determined by infrared analysis of 2,554 samples from 224 mothers. The mean contents of P, F, C, and energy (E, calculated from P, F, and C) were 9.0 g/L, 39.0 g/L, 71.9 g/L, and 696 kcal/L, respectively...... with a high P content, we have developed a "high-protein" milk with a P content of about 12 g/L (true protein) and an E content of about 725 kcal/L. Thus, by continuous monitoring of macronutrient content in human bank milk it is possible to develop a "high-protein" milk with sufficient P and E content....... The main results were as follows: the P and F contents increased slightly with increasing body mass index of the mother, the P content decreased with increasing amounts of milk delivered to the milk bank, and the F content was higher in mothers delivering large amounts of milk. By selecting incoming milk...

  12. Ruído escolar e sua implicação na atividade de ditado Influence of school noise on dictation activity

    Directory of Open Access Journals (Sweden)

    Graziela Cambruzzi Jaroszewski

    2007-03-01

    Full Text Available OBJETIVO: avaliar o nível de ruído nas salas de aula de primeira série do ensino fundamental, bem como verificar sua interferência durante as atividades de leitura e ditado. MÉTODOS: realizou-se a medição dos níveis de ruído segundo padrões ANSI em sete salas de aula de cinco escolas da rede municipal de ensino da cidade de Urussanga/SC durante as atividades de leitura e ditado. Posteriormente aplicou-se um questionário aos alunos e professores abordando a interferência do ruído nas atividades realizadas. Participaram da pesquisa 109 crianças sendo, 59 do gênero masculino e 50 do gênero feminino. RESULTADOS: os níveis de ruído presentes nas salas de aulas, variou de 59,5 a 71,3 dB(A. Quanto à percepção dos alunos e professores sobre o ruído, 94,5% dos alunos e 100% dos professores perceberam outras fontes sonoras durante as atividades, mas, apenas 52,39% dos alunos e 42,8% dos professores afirmaram interferência do ruído na aplicação das atividades. CONCLUSÃO: observou-se que o nível de ruído mesmo estando acima do proposto pelas normas nacionais, não interferiu no resultado do ditado. Por outro lado, os professores, principalmente das salas mais ruidosas, necessitaram elevar a voz durante a aplicação da atividade, queixando-se posteriormente de cansaço vocal.PURPOSE: to evaluate noise level in the classrooms of first grade children as well as, to verify its interference during reading and dictation activities. METHODS: measuring noise levels according to ANSI standards was performed in seven classrooms of five schools of the municipal network of teaching in the city of Urussanga, Santa Catarina during reading and dictation activities. Afterwards, a questionnaire was introduced to the students and teachers dealing with the interference of noise in the accomplished activities. 109 children participated in the survey and 59 were males and 50 females. RESULTS: noise levels present in the classrooms varied from 59

  13. A before-after control-impact assessment to understand the potential impacts of highway construction noise and activity on an endangered songbird.

    Science.gov (United States)

    Long, Ashley M; Colón, Melanie R; Bosman, Jessica L; Robinson, Dianne H; Pruett, Hannah L; McFarland, Tiffany M; Mathewson, Heather A; Szewczak, Joseph M; Newnam, J Cal; Morrison, Michael L

    2017-01-01

    Anthropogenic noise associated with highway construction and operation can have individual- and population-level consequences for wildlife (e.g., reduced densities, decreased reproductive success, behavioral changes). We used a before-after control-impact study design to examine the potential impacts of highway construction and traffic noise on endangered golden-cheeked warblers (Setophaga chrysoparia; hereafter warbler) in urban Texas. We mapped and monitored warbler territories before (2009-2011), during (2012-2013), and after (2014) highway construction at three study sites: a treatment site exposed to highway construction and traffic noise, a control site exposed only to traffic noise, and a second control site exposed to neither highway construction or traffic noise. We measured noise levels at varying distances from the highway at sites exposed to construction and traffic noise. We examined how highway construction and traffic noise influenced warbler territory density, territory placement, productivity, and song characteristics. In addition, we conducted a playback experiment within study sites to evaluate acute behavioral responses to highway construction noises. Noise decreased with increasing distance from the highways. However, noise did not differ between the construction and traffic noise sites or across time. Warbler territory density increased over time at all study sites, and we found no differences in warbler territory placement, productivity, behavior, or song characteristics that we can attribute to highway construction or traffic noise. As such, we found no evidence to suggest that highway construction or traffic noise had a negative effect on warblers during our study. Because human population growth will require recurring improvements to transportation infrastructure, understanding wildlife responses to anthropogenic noise associated with the construction and operation of roads is essential for effective management and recovery of prioritized

  14. Social and emotional values of sounds influence human (Homo sapiens) and non-human primate (Cercopithecus campbelli) auditory laterality.

    Science.gov (United States)

    Basile, Muriel; Lemasson, Alban; Blois-Heulin, Catherine

    2009-07-17

    The last decades evidenced auditory laterality in vertebrates, offering new important insights for the understanding of the origin of human language. Factors such as the social (e.g. specificity, familiarity) and emotional value of sounds have been proved to influence hemispheric specialization. However, little is known about the crossed effect of these two factors in animals. In addition, human-animal comparative studies, using the same methodology, are rare. In our study, we adapted the head turn paradigm, a widely used non invasive method, on 8-9-year-old schoolgirls and on adult female Campbell's monkeys, by focusing on head and/or eye orientations in response to sound playbacks. We broadcast communicative signals (monkeys: calls, humans: speech) emitted by familiar individuals presenting distinct degrees of social value (female monkeys: conspecific group members vs heterospecific neighbours, human girls: from the same vs different classroom) and emotional value (monkeys: contact vs threat calls; humans: friendly vs aggressive intonation). We evidenced a crossed-categorical effect of social and emotional values in both species since only "negative" voices from same class/group members elicited a significant auditory laterality (Wilcoxon tests: monkeys, T = 0 p = 0.03; girls: T = 4.5 p = 0.03). Moreover, we found differences between species as a left and right hemisphere preference was found respectively in humans and monkeys. Furthermore while monkeys almost exclusively responded by turning their head, girls sometimes also just moved their eyes. This study supports theories defending differential roles played by the two hemispheres in primates' auditory laterality and evidenced that more systematic species comparisons are needed before raising evolutionary scenario. Moreover, the choice of sound stimuli and behavioural measures in such studies should be the focus of careful attention.

  15. Social and emotional values of sounds influence human (Homo sapiens and non-human primate (Cercopithecus campbelli auditory laterality.

    Directory of Open Access Journals (Sweden)

    Muriel Basile

    Full Text Available The last decades evidenced auditory laterality in vertebrates, offering new important insights for the understanding of the origin of human language. Factors such as the social (e.g. specificity, familiarity and emotional value of sounds have been proved to influence hemispheric specialization. However, little is known about the crossed effect of these two factors in animals. In addition, human-animal comparative studies, using the same methodology, are rare. In our study, we adapted the head turn paradigm, a widely used non invasive method, on 8-9-year-old schoolgirls and on adult female Campbell's monkeys, by focusing on head and/or eye orientations in response to sound playbacks. We broadcast communicative signals (monkeys: calls, humans: speech emitted by familiar individuals presenting distinct degrees of social value (female monkeys: conspecific group members vs heterospecific neighbours, human girls: from the same vs different classroom and emotional value (monkeys: contact vs threat calls; humans: friendly vs aggressive intonation. We evidenced a crossed-categorical effect of social and emotional values in both species since only "negative" voices from same class/group members elicited a significant auditory laterality (Wilcoxon tests: monkeys, T = 0 p = 0.03; girls: T = 4.5 p = 0.03. Moreover, we found differences between species as a left and right hemisphere preference was found respectively in humans and monkeys. Furthermore while monkeys almost exclusively responded by turning their head, girls sometimes also just moved their eyes. This study supports theories defending differential roles played by the two hemispheres in primates' auditory laterality and evidenced that more systematic species comparisons are needed before raising evolutionary scenario. Moreover, the choice of sound stimuli and behavioural measures in such studies should be the focus of careful attention.

  16. An Auditing Approach for ERP Systems Examining Human Factors that Influence ERP User Satisfaction

    Directory of Open Access Journals (Sweden)

    Theodoros MITAKOS

    2010-01-01

    Full Text Available This paper tries to connect the successful implementation and operation of the ERP (Enterprise Resource Planning information systems with people and their characteristics through a pilot survey. It examines the human factors that influence ERP user satisfaction. The presented survey tests 14 hypotheses and is based on the model developed by Zviran, Pliskin & Levin [21]. An additional factor has been added to the specified model, the self-efficacy factor analyzed by Bandura [1]. The results are based on 250 ERP users that responded to the survey. The key findings that were revealed by data analysis were that none of the human socio-demographic characteristics do influence ERP user satisfaction. Additionally it was found that perceived usefulness and self-efficacy are the key directors of the ERP user satisfaction. Moreover suggestions are given about how the companies should handle ERP usage in order to develop the prerequisites for increasing user satisfaction and productivity accordingly.

  17. Some proves of integrated influence of geomagnetic activity and weather changes on human health

    CERN Document Server

    Khabarova, O V

    2008-01-01

    Our environment includes many factors, and each person on the Earth is permanently influenced by two of them: weather and magnetic field. It was found in the works of many investigators that the weather changes correlate with human health state. In the same time, disturbances of geomagnetic field (as one of the space weather manifestations) may influence bioobjects, including people. In this work we demonstrate the cumulative effect of different external factors (space weather and meteorological weather parameters) on human health on the base of medical experimental data (blood pressure and heart rate data rows for 86 people). It is shown that inclusion both solar-geomagnetic and weather parameters in simulation process give adjusting mixed parameter, which correlates with health state significantly better, than separated environmental parameters do.

  18. The spatially varying influence of humans on fire probability in North America

    Science.gov (United States)

    Parisien, Marc-André; Miller, Carol; Parks, Sean A.; DeLancey, Evan R.; Robinne, François-Nicolas; Flannigan, Mike D.

    2016-07-01

    Humans affect fire regimes by providing ignition sources in some cases, suppressing wildfires in others, and altering natural vegetation in ways that may either promote or limit fire. In North America, several studies have evaluated the effects of society on fire activity; however, most studies have been regional or subcontinental in scope and used different data and methods, thereby making continent-wide comparisons difficult. We circumvent these challenges by investigating the broad-scale impact of humans on fire activity using parallel statistical models of fire probability from 1984 to 2014 as a function of climate, enduring features (topography and percent nonfuel), lightning, and three indices of human activity (population density, an integrated metric of human activity [Human Footprint Index], and a measure of remoteness [roadless volume]) across equally spaced regions of the United States and Canada. Through a statistical control approach, whereby we account for the effect of other explanatory variables, we found evidence of non-negligible human-wildfire association across the entire continent, even in the most sparsely populated areas. A surprisingly coherent negative relationship between fire activity and humans was observed across the United States and Canada: fire probability generally diminishes with increasing human influence. Intriguing exceptions to this relationship are the continent’s least disturbed areas, where fewer humans equate to less fire. These remote areas, however, also often have lower lightning densities, leading us to believe that they may be ignition limited at the spatiotemporal scale of the study. Our results suggest that there are few purely natural fire regimes in North America today. Consequently, projections of future fire activity should consider human impacts on fire regimes to ensure sound adaptation and mitigation measures in fire-prone areas.

  19. Perception of human-derived risk influences choice at top of the food chain.

    Science.gov (United States)

    Cristescu, Bogdan; Stenhouse, Gordon B; Boyce, Mark S

    2013-01-01

    On human-used landscapes, animal behavior is a trade-off between maximizing fitness and minimizing human-derived risk. Understanding risk perception in wildlife can allow mitigation of anthropogenic risk, with benefits to long-term animal fitness. Areas where animals choose to rest should minimize risk from predators, which for large carnivores typically equate to humans. We hypothesize that high human activity leads to selection for habitat security, whereas low activity enables trading security for forage. We investigated selection of resting (bedding) sites by GPS radiocollared adult grizzly bears (n = 10) in a low density population on a multiple-use landscape in Canada. We compared security and foods at resting and random locations while accounting for land use, season, and time of day. On reclaimed mines with low human access, bears selected high horizontal cover far from trails, but did not avoid open (herbaceous) areas, resting primarily at night. In protected areas bears also bedded at night, in areas with berry shrubs and Hedysarum spp., with horizontal cover selected in the summer, during high human access. On public lands with substantial human recreation, bears bedded at day, selected resting sites with high horizontal cover in the summer and habitat edges, with bedding associated with herbaceous foods. These spatial and temporal patterns of selection suggest that bears perceive human-related risk differentially in relation to human activity level, season and time of day, and employ a security-food trade-off strategy. Although grizzly bears are presently not hunted in Alberta, their perceived risks associated with humans influence resting-site selection.

  20. Perception of human-derived risk influences choice at top of the food chain.

    Directory of Open Access Journals (Sweden)

    Bogdan Cristescu

    Full Text Available On human-used landscapes, animal behavior is a trade-off between maximizing fitness and minimizing human-derived risk. Understanding risk perception in wildlife can allow mitigation of anthropogenic risk, with benefits to long-term animal fitness. Areas where animals choose to rest should minimize risk from predators, which for large carnivores typically equate to humans. We hypothesize that high human activity leads to selection for habitat security, whereas low activity enables trading security for forage. We investigated selection of resting (bedding sites by GPS radiocollared adult grizzly bears (n = 10 in a low density population on a multiple-use landscape in Canada. We compared security and foods at resting and random locations while accounting for land use, season, and time of day. On reclaimed mines with low human access, bears selected high horizontal cover far from trails, but did not avoid open (herbaceous areas, resting primarily at night. In protected areas bears also bedded at night, in areas with berry shrubs and Hedysarum spp., with horizontal cover selected in the summer, during high human access. On public lands with substantial human recreation, bears bedded at day, selected resting sites with high horizontal cover in the summer and habitat edges, with bedding associated with herbaceous foods. These spatial and temporal patterns of selection suggest that bears perceive human-related risk differentially in relation to human activity level, season and time of day, and employ a security-food trade-off strategy. Although grizzly bears are presently not hunted in Alberta, their perceived risks associated with humans influence resting-site selection.

  1. Complexity of the influence of gangliosides on histamine release from human basophils and rat mast cells

    DEFF Research Database (Denmark)

    Jensen, C; Svendsen, U G; Thastrup, Ole;

    1987-01-01

    The influence of exogenous addition of gangliosides on histamine release from human basophils and rat mast cells was examined in vitro. Gangliosides dose-dependently inhibited histamine release, and this inhibition was dependent on the ganglioside sialic acid content, since GT1b, having 3 sialic...... was reflected in the sensitivity of the cells to extracellular calcium, since inhibition of the release could be counteracted by increasing the extracellular concentration of calcium....

  2. Do commitment based human resource practices influence job embeddedness and intention to quit?

    Directory of Open Access Journals (Sweden)

    Debjani Ghosh

    2015-12-01

    Full Text Available This empirical paper provides evidence that commitment based human resource practices (CBHRP influence employees' turnover intentions by embedding newcomers more extensively into organisations. The study was conducted with 501 managers in 19 financial service organisations in India. Results reveal that CBHRP enable organisations to actively embed employees. The results also indicate that on-the-job embeddedness (on-the-JE is negatively related to turnover intentions and mediates relationships between CBHRP and employees' intention to quit.

  3. The Influence of Social Networking Sites on Recruiting Human Resources in the Czech Republic

    Directory of Open Access Journals (Sweden)

    Bohmova Lucie

    2015-02-01

    Full Text Available Background: This paper is focused on the usage of social networking sites (SNS for human resources departments in the process of hiring new employees. It also maps the development and influence of SNS on recruiter's behavior and customs. The main aim is to find out, whether SNS could/will replace traditional online job boards in the Czech Republic. The motivation for the research is to determine whether SNS can be used for serious and practical business purposes.

  4. Progressing the state of knowledge on the human influence on hydrological droughts through case studies

    Science.gov (United States)

    Rangecroft, Sally; Van Loon, Anne; Bosman, Marianne; Wanders, Niko; Di Baldassarre, Giuliano; AghaKouchak, Amir

    2017-04-01

    Human activities can have a large influence on changes in the hydrological system and hydrological extremes, more than climate variability and climate change in some cases. However, there are currently only a limited number of studies which aim to quantify the human impact on hydrological droughts. Here we present a synthesis study of existing and new results that aims to summarize and quantify the anthropogenic impact on hydrological drought from case studies and observations. By combining a large number of case studies, we allow conclusions to be drawn about the effects of different human activities. This work suggests ways forward to increase our understanding on how human activities are influencing drought characteristics; invaluable information for water resource management and adaptation. During this project, the impact of different human activities (e.g. water abstraction, reservoir building, urbanisation, etc) on drought frequency, duration and deficit has been calculated in a consistent manner, allowing for an improved understanding to how they have impacted droughts. This consistent methodology is a necessary element for this comparative hydrology exercise, yet we use one which is flexible and applicable to different case study set ups and data availability. The methodology used here depends on available observation data, with three possible approaches: i) paired catchment approach; ii) upstream-downstream comparison; iii) observation modelling framework. The synthesised results of the existing and new case studies cover a number of human activities, hydro-climatic and socio-economic contexts. In particular, we remove the climate dependency in the results by using case studies from multiple climatic regions, including UK, Italy, US, Australia, Mexico and Chile. For groundwater abstraction, it is clear across all the relevant case studies that abstraction activities worsen drought events. This is especially prominent in the deficit volumes, with nearly all

  5. Contralateral Noise Stimulation Delays P300 Latency in School-Aged Children.

    Directory of Open Access Journals (Sweden)

    Thalita Ubiali

    Full Text Available The auditory cortex modulates auditory afferents through the olivocochlear system, which innervates the outer hair cells and the afferent neurons under the inner hair cells in the cochlea. Most of the studies that investigated the efferent activity in humans focused on evaluating the suppression of the otoacoustic emissions by stimulating the contralateral ear with noise, which assesses the activation of the medial olivocochlear bundle. The neurophysiology and the mechanisms involving efferent activity on higher regions of the auditory pathway, however, are still unknown. Also, the lack of studies investigating the effects of noise on human auditory cortex, especially in peadiatric population, points to the need for recording the late auditory potentials in noise conditions. Assessing the auditory efferents in schoolaged children is highly important due to some of its attributed functions such as selective attention and signal detection in noise, which are important abilities related to the development of language and academic skills. For this reason, the aim of the present study was to evaluate the effects of noise on P300 responses of children with normal hearing.P300 was recorded in 27 children aged from 8 to 14 years with normal hearing in two conditions: with and whitout contralateral white noise stimulation.P300 latencies were significantly longer at the presence of contralateral noise. No significant changes were observed for the amplitude values.Contralateral white noise stimulation delayed P300 latency in a group of school-aged children with normal hearing. These results suggest a possible influence of the medial olivocochlear activation on P300 responses under noise condition.

  6. Influence of temporal noise on the skin blood flow measurements performed by cooled thermal imaging camera: limit possibilities within each physiological frequency range

    Science.gov (United States)

    Sagaidachnyi, A. A.; Volkov, I. U.; Fomin, A. V.

    2016-04-01

    This paper describes limit possibilities of modern cooled thermal imaging cameras as a tool for estimation of blood flow oscillations at the surface of living body. Skin temperature oscillations, as we assumed, are a consequence of the blood flow oscillations. We considered the temperature sensitivity 0.01-0.02 °C as a typical for the most of modern cooled long wave thermal imaging cameras. Fourier filter used to investigate the temperature signal separately within endothelial, neurogenic, myogenic, respiratory and cardiac frequency ranges. The level of temporal noise has been estimated during measurements of no living body with stabilized temperature ~ 24°C. The level of temperature oscillations has been calculated for the group of healthy subjects within each frequency range. Thus, we were able to determine signal-to-noise ratio within frequency band [0.001, 1] Hz. As a result, we determine that skin temperature oscillations measured by thermal imaging camera with sensitivity 0.02°C have the upper frequency limit ~ 0.2 Hz. In other words, within the respiratory and cardiac frequency ranges of blood flow oscillations the noise level exceeds signal one, and temperature measurements at the skin surface are practically useless. The endothelial, neurogenic and myogenic components of the temperature oscillations contain ~98% of the total spectral power of the signal. We have plot the empirical extrapolated curve of sensitivity of thermal imaging camera vs. frequency of the temperature oscillations. The data analysis shows that measurements of skin temperature oscillations within respiratory and cardiac ranges require the temperature sensitivity at least ~ 0.01°C and 0.001°C, respectively.

  7. Iodine potassium iodide improves the contrast-to-noise ratio of micro-computed tomography images of the human middle ear.

    Science.gov (United States)

    Rohani, S A; Ghomashchi, S; Umoh, J; Holdsworth, D W; Agrawal, S K; Ladak, H M

    2016-12-01

    High-resolution imaging of middle-ear geometry is necessary for finite-element modeling. Although micro-computed tomography (microCT) is widely used because of its ability to image bony structures of the middle ear, it is difficult to visualize soft tissues - including the tympanic membrane and the suspensory ligaments/tendons - because of lack of contrast. The objective of this research is to quantitatively evaluate the efficacy of iodine potassium iodide (IKI) solution as a contrast agent. Six human temporal bones were used in this experiment, which were obtained in right-left pairs, from three cadaveric heads. All bones were fixed using formaldehyde. Three bones (one from each pair) were stained in IKI solution for 2 days, whereas the other three were not stained. Samples were scanned using a microCT system at a resolution of 20 μm. Eight soft tissues in the middle ear were segmented: anterior mallear ligament, incudomallear joint, lateral mallear ligament, posterior incudal ligament, stapedial annular ligament, stapedius muscle, tympanic membrane and tensor tympani muscle. Contrast-to-noise ratios (CNRs) of each soft tissue were calculated for each temporal bone. Combined CNRs of the soft tissues in unstained samples were 6.1 ± 3.0, whereas they were 8.1 ± 2.7 in stained samples. Results from Welch's t-test indicate significant difference between the two groups at a 95% confidence interval. Results for paired t-tests for each of the individual soft tissues also indicated significant improvement of contrast in all tissues after staining. Relatively large soft tissues in the middle ear such as the tympanic membrane and the tensor tympani muscle were impacted by staining more than smaller tissues such as the stapedial annular ligament. The increase in contrast with IKI solution confirms its potential application in automatic segmentation of the middle-ear soft tissues.

  8. Noise Exclusion Ability in Infants

    Directory of Open Access Journals (Sweden)

    Geroldene Tsui

    2011-05-01

    Full Text Available An important perceptual ability is to filter out background distractions from relevant information. However, prior research has not identified when this begins in humans. Our study aims to investigate whether noise exclusion ability occurs in infancy. Infants' contrast sensitivity function (CSF was measured by a Baynesian adaptive inference method. Infants' attention was directed to the middle of a monitor where an 8.72 degree static Gabor grating was presented on the left or right side of the monitor. In half the trials, the grating was presented against a gray background; in the other half, against a 16% contrast random-dot noise background. The experimenter and two independent coders judged which side the infants gazed at (force-choice preferential looking paradigm. One-hundred babies aged from 4 to 10 months satisfied the 70% interrater consistency criterion for inclusion. Four parameters defined the best-fitted CSF for each infant. Of these, peak spatial frequency, bandwidth and truncation of CSF were similar in conditions with and without noise. The peak gain estimate was most significantly impaired by external noise, but a marked 31% improvement was observed in 7- to 10-month-olds. This may be the first sign of development of human's noise exclusion ability, and is worth further study.

  9. Human Response to Aircraft Noise

    NARCIS (Netherlands)

    Kroesen, M.

    2011-01-01

    How can it be that one person is extremely annoyed by the sounds of aircrafts, while his neighbour claims not to be bothered at all? The present thesis attempts to explain this observation by applying a range of quantitative methods to field data gathered among residents living near large airports.

  10. Can Noise Kill People?

    Institute of Scientific and Technical Information of China (English)

    刘玲娣

    2007-01-01

    Someone is singing next door,but you feel unhappy because her singing is just making a noise.We know that too much noise makes people feel terrible. Scientists are still trying to find out more about noise,but already it is known that a noise of over 85 decibels can make some people tired and anxious.

  11. Active Noise Control for Dishwasher noise

    Science.gov (United States)

    Lee, Nokhaeng; Park, Youngjin

    2016-09-01

    The dishwasher is a useful home appliance and continually used for automatically washing dishes. It's commonly placed in the kitchen with built-in style for practicality and better use of space. In this environment, people are easily exposed to dishwasher noise, so it is an important issue for the consumers, especially for the people living in open and narrow space. Recently, the sound power levels of the noise are about 40 - 50 dBA. It could be achieved by removal of noise sources and passive means of insulating acoustical path. For more reduction, such a quiet mode with the lower speed of cycle has been introduced, but this deteriorates the washing capacity. Under this background, we propose active noise control for dishwasher noise. It is observed that the noise is propagating mainly from the lower part of the front side. Control speakers are placed in the part for the collocation. Observation part of estimating sound field distribution and control part of generating the anti-noise are designed for active noise control. Simulation result shows proposed active noise control scheme could have a potential application for dishwasher noise reduction.

  12. PBDE levels in human milk: the situation in Germany and potential influencing factors - a controlled study

    Energy Technology Data Exchange (ETDEWEB)

    Vieth, B.; Mielke, H.; Ostermann, B.; Ruediger, T. [Federal Inst. for Risk Assessment, Berlin (Germany); Herrmann, T.; Paepke, O. [ERGO Forschungsgesellschaft mbH, Hamburg (Germany)

    2004-09-15

    An exponential increase of PBDE levels in breast milk from Sweden between 1972 and 1997 has been reported, which is in contrast to the continuous decline of other chlorinated POPs in breast milk. Also in blood samples from Germany, an increasing trend has been observed during the period from 1985 to 1999. The knowledge about human exposure pathways, which contribute to the PBDE body burden, is very limited. Consumption of food of animal origin, inhalation or ingestion of dust and further factors possibly influencing the PBDE levels in human matrices, like age, breast-feeding or smoking are under discussion. Only a few data on PBDE levels in breast milk from Germany have been published. To fill the data gaps, a controlled study was started in 2001 to characterise the PBDE levels in human milk from Germany with special efforts to identify and quantify deca-BDE-209. Furthermore, it was intended to verify potential factors possibly influencing PBDE levels. Two main hypotheses were proposed: (1) Are PBDE levels in breast milk from mothers consuming traditional food (omnivores) higher than those found in breast milk from mothers consuming vegetarian or vegan food? and (2) Are the PBDE levels found in human milk after a three-months period of breast-feeding lower than those detected at the beginning or does breast feeding result in a lower body burden, respectively? This paper summarises preliminary results. Further analytical data and results of data evaluation will be presented at the conference.

  13. Large-scale identification of sequence variants influencing human transcription factor occupancy in vivo.

    Science.gov (United States)

    Maurano, Matthew T; Haugen, Eric; Sandstrom, Richard; Vierstra, Jeff; Shafer, Anthony; Kaul, Rajinder; Stamatoyannopoulos, John A

    2015-12-01

    The function of human regulatory regions depends exquisitely on their local genomic environment and on cellular context, complicating experimental analysis of common disease- and trait-associated variants that localize within regulatory DNA. We use allelically resolved genomic DNase I footprinting data encompassing 166 individuals and 114 cell types to identify >60,000 common variants that directly influence transcription factor occupancy and regulatory DNA accessibility in vivo. The unprecedented scale of these data enables systematic analysis of the impact of sequence variation on transcription factor occupancy in vivo. We leverage this analysis to develop accurate models of variation affecting the recognition sites for diverse transcription factors and apply these models to discriminate nearly 500,000 common regulatory variants likely to affect transcription factor occupancy across the human genome. The approach and results provide a new foundation for the analysis and interpretation of noncoding variation in complete human genomes and for systems-level investigation of disease-associated variants.

  14. Diurnally varying annoyance due to railway and road traffic noise; Laermbelaestigung durch Strassen- und Schienenverkehr zu unterschiedlichen Tageszeiten

    Energy Technology Data Exchange (ETDEWEB)

    Schreckenberg, D. [Zentrum fuer Angewandte Psychologie, Umwelt- und Sozialforschung (ZEUS GmbH), Bochum (Germany); Guski, R. [Ruhr-Univ. Bochum, Fakultaet fuer Psychologie, Bochum (Germany)

    2005-07-01

    One of the most prominent non-auditory effects of noise influencing the life quality of human beings is the disturbance of activities (i.e. communicating, relaxing, working, sleeping). The disturbance of activities results in noise annoyance, and in the long run may lead to further health effects. Due to the fact that activities vary diurnally it is plausible to assume that peoples'' responses to noise differ depending on the times of day. The aim of the study, which is part of the German research network ''Quiet Traffic'' is to provide empirical data of dose-response relationships for different times of day (excluding the night). 1110 residents from four areas with dominant road traffic noise (683 subjects) and from two areas with dominant railway noise (427 subjects) have been asked in a face-to-face interview for contentment with house and living environment and noise reactions. 131 persons of the total sample took part in an additional study (experience-sampling study) in which the hourly noise annoyance was measured for three consecutive days using a handheld computer. For each subject individual source-specific immission noise level for each hour of the day has been calculated. There is higher annoyance due to road traffic noise in the late afternoon/evening from 4 pm to 7 pm. For railway noise higher annoyance is reported in the evening from 6 pm to 10 am. The reported differences in noise annoyance depending on the times of day are higher with increasing noise level. (orig.)

  15. Mechanics of underwater noise

    CERN Document Server

    Ross, Donald

    1976-01-01

    Mechanics of Underwater Noise elucidates the basic mechanisms by which noise is generated, transmitted by structures and radiated into the sea. Organized into 10 chapters, this book begins with a description of noise, decibels and levels, significance of spectra, and passive sonar equation. Subsequent chapters discuss sound waves in liquids; acoustic radiation fundamentals; wind-generated ocean ambient noise; vibration isolation and structural damping; and radiation by plate flexural vibrations. Other chapters address cavitation, propeller cavitation noise, radiation by fluctuating-force (dipo

  16. Variation in human mate choice: simultaneously investigating heritability, parental influence, sexual imprinting, and assortative mating.

    Science.gov (United States)

    Zietsch, Brendan P; Verweij, Karin J H; Heath, Andrew C; Martin, Nicholas G

    2011-05-01

    Human mate choice is central to individuals' lives and to the evolution of the species, but the basis of variation in mate choice is not well understood. Here we looked at a large community-based sample of twins and their partners and parents ([Formula: see text] individuals) to test for genetic and family environmental influences on mate choice, while controlling for and not controlling for the effects of assortative mating. Key traits were analyzed, including height, body mass index, age, education, income, personality, social attitudes, and religiosity. This revealed near-zero genetic influences on male and female mate choice over all traits and no significant genetic influences on mate choice for any specific trait. A significant family environmental influence was found for the age and income of females' mate choices, possibly reflecting parental influence over mating decisions. We also tested for evidence of sexual imprinting, where individuals acquire mate-choice criteria during development by using their opposite-sex parent as the template of a desirable mate; there was no such effect for any trait. The main discernible pattern of mate choice was assortative mating; we found that partner similarity was due to initial choice rather than convergence and also at least in part to phenotypic matching.

  17. How Angular Velocity Features and Different Gyroscope Noise Types Interact and Determine Orientation Estimation Accuracy

    Directory of Open Access Journals (Sweden)

    Ilaria Pasciuto

    2015-09-01

    Full Text Available In human movement analysis, 3D body segment orientation can be obtained through the numerical integration of gyroscope signals. These signals, however, are affected by errors that, for the case of micro-electro-mechanical systems, are mainly due to: constant bias, scale factor, white noise, and bias instability. The aim of this study is to assess how the orientation estimation accuracy is affected by each of these disturbances, and whether it is influenced by the angular velocity magnitude and 3D distribution across the gyroscope axes. Reference angular velocity signals, either constant or representative of human walking, were corrupted with each of the four noise types within a simulation framework. The magnitude of the angular velocity affected the error in the orientation estimation due to each noise type, except for the white noise. Additionally, the error caused by the constant bias was also influenced by the angular velocity 3D distribution. As the orientation error depends not only on the noise itself but also on the signal it is applied to, different sensor placements could enhance or mitigate the error due to each disturbance, and special attention must be paid in providing and interpreting measures of accuracy for orientation estimation algorithms.

  18. How Angular Velocity Features and Different Gyroscope Noise Types Interact and Determine Orientation Estimation Accuracy.

    Science.gov (United States)

    Pasciuto, Ilaria; Ligorio, Gabriele; Bergamini, Elena; Vannozzi, Giuseppe; Sabatini, Angelo Maria; Cappozzo, Aurelio

    2015-01-01

    In human movement analysis, 3D body segment orientation can be obtained through the numerical integration of gyroscope signals. These signals, however, are affected by errors that, for the case of micro-electro-mechanical systems, are mainly due to: constant bias, scale factor, white noise, and bias instability. The aim of this study is to assess how the orientation estimation accuracy is affected by each of these disturbances, and whether it is influenced by the angular velocity magnitude and 3D distribution across the gyroscope axes. Reference angular velocity signals, either constant or representative of human walking, were corrupted with each of the four noise types within a simulation framework. The magnitude of the angular velocity affected the error in the orientation estimation due to each noise type, except for the white noise. Additionally, the error caused by the constant bias was also influenced by the angular velocity 3D distribution. As the orientation error depends not only on the noise itself but also on the signal it is applied to, different sensor placements could enhance or mitigate the error due to each disturbance, and special attention must be paid in providing and interpreting measures of accuracy for orientation estimation algorithms.

  19. Research on Emerging and Descending Aircraft Noise

    Directory of Open Access Journals (Sweden)

    Monika Bartkevičiūtė

    2013-12-01

    Full Text Available Along with an increase in the aircraft engine power and growth in air traffic, noise level at airports and their surrounding environs significantly increases. Aircraft noise is high level noise spreading within large radius and intensively irritating the human body. Air transport is one of the main sources of noise having a particularly strong negative impact on the environment. The article deals with activities and noises taking place in the largest nationwide Vilnius International Airport.The level of noise and its dispersion was evaluated conducting research on the noise generated by emerging and descending aircrafts in National Vilnius Airport. Investigation was carried out at 2 measuring points located in a residential area. There are different types of aircrafts causing different sound levels. It has been estimated the largest exceedances that occur when an aircraft is approaching. In this case, the noisiest types of aircrafts are B733, B738 and AT72. The sound level varies from 70 to 85 dBA. The quietest aircrafts are RJ1H and F70. When taking off, the equivalent of the maximum sound level value of these aircrafts does not exceed the authorized limits. The paper describes the causes of noise in aircrafts, the sources of origin and the impact of noise on humans and the environment.Article in Lithuanian

  20. ETM study of electroporation influence on cell morphology in human malignant melanoma and human primary gingival fibroblast cells

    Institute of Scientific and Technical Information of China (English)

    Nina Skolucka; Malgorzata Daczewska; Jolanta Saczko; Agnieszka Chwilkowska; Anna Choromanska; Malgorzata Kotulska; Iwona Kaminska; Julita Kulbacka

    2011-01-01

    Objective:To estimate electroporation (EP) influence on malignant and normal cells.Methods:Two cell lines including human malignant melanoma (Me-45) and normal human gingival fibroblast (HGFs) were used. EP parameters were the following:250,1000,1750,2500 V/cm;50 μs by5 impulses for every case. The viability of cells after EP was estimated byMTT assay. The ultrastructural analysis was observed by transmission electron microscope (ZeissEM900). Results:In the current study we observed the intracellular effect followingEP on Me-45 and HGF cells. At the conditions applied, we did not observe any significant damage of mitochondrial activity in both cell lines treated byEP. Conversely, we showed thatEP in some conditions can stimulate cells to proliferation. Some changes induced byEP were only visible in electron microscopy. In fibroblast cells we observed significant changes in lower parameters ofEP (250 and1000 V/cm). After applying higher electric field intensities (2500 V/cm) we detected many vacuoles, myelin-like bodies and swallowed endoplasmic reticulum. In melanoma cells such strong pathological modifications afterEP were not observed, in comparison with control cells. The ultrastructure of both treated cell lines was changed according to the applied parameters ofEP.Conclusions:We can claim thatEP conditions are cell line dependent. In terms of the intracellular morphology, human fibroblasts are more sensitive to electric field as compared with melanoma cells. Optimal conditions should be determined for each cell line. Summarizing our study, we can conclude thatEP is not an invasive method for human normal and malignant cells. This technique can be safely applied in chemotherapy for delivering drugs into tumor cells.

  1. ETM study of electroporation influence on cell morphology in human malignant melanoma and human primary gingival fibroblast cells.

    Science.gov (United States)

    Skolucka, Nina; Daczewska, Malgorzata; Saczko, Jolanta; Chwilkowska, Agnieszka; Choromanska, Anna; Kotulska, Malgorzata; Kaminska, Iwona; Kulbacka, Julita

    2011-04-01

    To estimate electroporation (EP) influence on malignant and normal cells. Two cell lines including human malignant melanoma (Me-45) and normal human gingival fibroblast (HGFs) were used. EP parameters were the following: 250, 1 000, 1 750, 2 500 V/cm; 50 µs by 5 impulses for every case. The viability of cells after EP was estimated by MTT assay. The ultrastructural analysis was observed by transmission electron microscope (Zeiss EM 900). In the current study we observed the intracellular effect following EP on Me-45 and HGF cells. At the conditions applied, we did not observe any significant damage of mitochondrial activity in both cell lines treated by EP. Conversely, we showed that EP in some conditions can stimulate cells to proliferation. Some changes induced by EP were only visible in electron microscopy. In fibroblast cells we observed significant changes in lower parameters of EP (250 and 1 000 V/cm). After applying higher electric field intensities (2 500 V/cm) we detected many vacuoles, myelin-like bodies and swallowed endoplasmic reticulum. In melanoma cells such strong pathological modifications after EP were not observed, in comparison with control cells. The ultrastructure of both treated cell lines was changed according to the applied parameters of EP. We can claim that EP conditions are cell line dependent. In terms of the intracellular morphology, human fibroblasts are more sensitive to electric field as compared with melanoma cells. Optimal conditions should be determined for each cell line. Summarizing our study, we can conclude that EP is not an invasive method for human normal and malignant cells. This technique can be safely applied in chemotherapy for delivering drugs into tumor cells.

  2. Influence of fluoroquinolones on phagocytosis and killing of Candida albicans by human polymorphonuclear neutrophils.

    Science.gov (United States)

    Gruger, Thomas; Morler, Caroline; Schnitzler, Norbert; Brandenburg, Kerstin; Nidermajer, Sabine; Horre, Regine; Zundorf, Josef

    2008-11-01

    Candida albicans infections often occur during or shortly after antibacterial treatment. Phagocytosis by polymorphonuclear neutrophil granulocytes (PMN) is the most important primarily defence mechanism against C. albicans. Certain antibiotics such as some fluoroquinolones (FQ) are known to influence phagocyte functions. Thus, we investigated the influence of older and newer FQ on the phagocytosis and killing of C. albicans by human PMN paying special attention to CD11b expression of these cells as an indicator of the degree of their activation. In order to obtain comprehensive and comparable results we tested 13 FQ over a wide range of concentrations and in a time dependent manner in a standardized approach. When used at therapeutic concentrations, the FQ tested did not influence to a clinically significant degree the phagocytosis or the killing of C. albicans by human PMN and also not their activation. However, at high concentrations those FQ with cyclopropyl-moiety at position N1 showed increase in CD11b expression and diminished phagocytosis and oxidative burst.

  3. Human Impacts and Climate Change Influence Nestedness and Modularity in Food-Web and Mutualistic Networks.

    Directory of Open Access Journals (Sweden)

    Kazuhiro Takemoto

    Full Text Available Theoretical studies have indicated that nestedness and modularity-non-random structural patterns of ecological networks-influence the stability of ecosystems against perturbations; as such, climate change and human activity, as well as other sources of environmental perturbations, affect the nestedness and modularity of ecological networks. However, the effects of climate change and human activities on ecological networks are poorly understood. Here, we used a spatial analysis approach to examine the effects of climate change and human activities on the structural patterns of food webs and mutualistic networks, and found that ecological network structure is globally affected by climate change and human impacts, in addition to current climate. In pollination networks, for instance, nestedness increased and modularity decreased in response to increased human impacts. Modularity in seed-dispersal networks decreased with temperature change (i.e., warming, whereas food web nestedness increased and modularity declined in response to global warming. Although our findings are preliminary owing to data-analysis limitations, they enhance our understanding of the effects of environmental change on ecological communities.

  4. The influence of genomic context on mutation patterns in the human genome inferred from rare variants.

    Science.gov (United States)

    Schaibley, Valerie M; Zawistowski, Matthew; Wegmann, Daniel; Ehm, Margaret G; Nelson, Matthew R; St Jean, Pamela L; Abecasis, Gonçalo R; Novembre, John; Zöllner, Sebastian; Li, Jun Z

    2013-12-01

    Understanding patterns of spontaneous mutations is of fundamental interest in studies of human genome evolution and genetic disease. Here, we used extremely rare variants in humans to model the molecular spectrum of single-nucleotide mutations. Compared to common variants in humans and human-chimpanzee fixed differences (substitutions), rare variants, on average, arose more recently in the human lineage and are less affected by the potentially confounding effects of natural selection, population demographic history, and biased gene conversion. We analyzed variants obtained from a population-based sequencing study of 202 genes in >14,000 individuals. We observed considerable variability in the per-gene mutation rate, which was correlated with local GC content, but not recombination rate. Using >20,000 variants with a derived allele frequency ≤ 10(-4), we examined the effect of local GC content and recombination rate on individual variant subtypes and performed comparisons with common variants and substitutions. The influence of local GC content on rare variants differed from that on common variants or substitutions, and the differences varied by variant subtype. Furthermore, recombination rate and recombination hotspots have little effect on rare variants of any subtype, yet both have a relatively strong impact on multiple variant subtypes in common variants and substitutions. This observation is consistent with the effect of biased gene conversion or selection-dependent processes. Our results highlight the distinct biases inherent in the initial mutation patterns and subsequent evolutionary processes that affect segregating variants.

  5. New genetic and linguistic analyses show ancient human influence on baobab evolution and distribution in Australia.

    Science.gov (United States)

    Rangan, Haripriya; Bell, Karen L; Baum, David A; Fowler, Rachael; McConvell, Patrick; Saunders, Thomas; Spronck, Stef; Kull, Christian A; Murphy, Daniel J

    2015-01-01

    This study investigates the role of human agency in the gene flow and geographical distribution of the Australian baobab, Adansonia gregorii. The genus Adansonia is a charismatic tree endemic to Africa, Madagascar, and northwest Australia that has long been valued by humans for its multiple uses. The distribution of genetic variation in baobabs in Africa has been partially attributed to human-mediated dispersal over millennia, but this relationship has never been investigated for the Australian species. We combined genetic and linguistic data to analyse geographic patterns of gene flow and movement of word-forms for A. gregorii in the Aboriginal languages of northwest Australia. Comprehensive assessment of genetic diversity showed weak geographic structure and high gene flow. Of potential dispersal vectors, humans were identified as most likely to have enabled gene flow across biogeographic barriers in northwest Australia. Genetic-linguistic analysis demonstrated congruence of gene flow patterns and directional movement of Aboriginal loanwords for A. gregorii. These findings, along with previous archaeobotanical evidence from the Late Pleistocene and Holocene, suggest that ancient humans significantly influenced the geographic distribution of Adansonia in northwest Australia.

  6. New genetic and linguistic analyses show ancient human influence on baobab evolution and distribution in Australia.

    Directory of Open Access Journals (Sweden)

    Haripriya Rangan

    Full Text Available This study investigates the role of human agency in the gene flow and geographical distribution of the Australian baobab, Adansonia gregorii. The genus Adansonia is a charismatic tree endemic to Africa, Madagascar, and northwest Australia that has long been valued by humans for its multiple uses. The distribution of genetic variation in baobabs in Africa has been partially attributed to human-mediated dispersal over millennia, but this relationship has never been investigated for the Australian species. We combined genetic and linguistic data to analyse geographic patterns of gene flow and movement of word-forms for A. gregorii in the Aboriginal languages of northwest Australia. Comprehensive assessment of genetic diversity showed weak geographic structure and high gene flow. Of potential dispersal vectors, humans were identified as most likely to have enabled gene flow across biogeographic barriers in northwest Australia. Genetic-linguistic analysis demonstrated congruence of gene flow patterns and directional movement of Aboriginal loanwords for A. gregorii. These findings, along with previous archaeobotanical evidence from the Late Pleistocene and Holocene, suggest that ancient humans significantly influenced the geographic distribution of Adansonia in northwest Australia.

  7. The influence of facility design and human resource management on health care professionals.

    Science.gov (United States)

    Sadatsafavi, Hessam; Walewski, John; Shepley, Mardelle M

    2015-01-01

    Cost control of health care services is a strategic concern for organizations. To lower costs, some organizations reduce staffing levels. However, this may not be worth the trade-off, as the quality of services will likely be reduced, morale among health care providers tends to suffer, and patient satisfaction is likely to decline. The potential synergy between human resource management and facility design and operation was investigated to achieve the goal of providing cost containment strategies without sacrificing the quality of services and the commitment of employees. About 700 health care professionals from 10 acute-care hospitals participated in this cross-sectional study. The authors used structural equation modeling to test whether employees' evaluations of their physical work environment and human resource practices were significantly associated with lower job-related anxiety, higher job satisfaction, and higher organizational commitment. The analysis found that employees' evaluations of their physical work environment and human resource practices influenced their job-related feelings and attitudes. Perceived organizational support mediated this relationship. The study also found a small but positive interaction effect between the physical work environment and human resource practices. The influence of physical work environment was small, mainly because of the high predictive value of human resource practices and strong confounding variables included in the analysis. This study specifically showed the role of facility design in reducing job-related anxiety among caregivers. Preliminary evidence is provided that facility design can be used as a managerial tool for improving job-related attitudes and feelings of employees and earning their commitment. Providing a healthy and safe work environment can be perceived by employees as an indication that the organization respects them and cares about their well-being, which might be reciprocated with higher levels

  8. Does Fertility Status Influence Impulsivity and Risk Taking in Human Females? Adaptive Influences on Intertemporal Choice and Risky Decision Making

    Directory of Open Access Journals (Sweden)

    Farnaz Kaighobadi

    2013-07-01

    Full Text Available Informed by the research on adaptive decision making in other animal species, this study investigated human females' intertemporal and risky choices across the ovulatory cycle. We tested the hypothesis that at peak fertility, women who are exposed to environments that signal availability of higher quality mates (by viewing images of attractive males, become more impulsive and risk-seeking in economic decision tasks. To test this, we collected intertemporal and risky choice measures before and after exposure to images of either attractive males or neutral landscapes both at peak and low fertility conditions. The results showed an interaction between women's fertility status and image type, such that women at peak fertility viewing images of attractive men chose the smaller, sooner monetary reward option less than women at peak fertility viewing neutral images. Neither fertility status nor image type influenced risky choice. Thus, though exposure to images of men altered intertemporal choices at peak fertility, this occurred in the opposite direction than predicted—i.e., women at peak fertility became less impulsive. Nevertheless, the results of the current study provide evidence for shifts in preferences over the ovulatory cycle and opens future research on economic decision making.

  9. Vessel noise pollution as a human threat to fish: assessment of the stress response in gilthead sea bream (Sparus aurata, Linnaeus 1758).

    Science.gov (United States)

    Celi, Monica; Filiciotto, Francesco; Maricchiolo, Giulia; Genovese, Lucrezia; Quinci, Enza Maria; Maccarrone, Vincenzo; Mazzola, Salvatore; Vazzana, Mirella; Buscaino, Giuseppa

    2016-04-01

    This study examined the effects of boat noise pollution on the stress indices of gilthead sea bream (Sparus aurata, Linnaeus 1758). To assess the stress response in these fish, biometric values and plasma parameters such as ACTH, cortisol, glucose, lactate, haematocrit, Hsp70, total protein, cholesterol, triglycerides and osmolarity were analysed. After acclimatization of the animals, the experiment was carried out in a tank fitted with underwater speakers where the fish were exposed to sound treatments (in duplicate) consisting of: 10 days of no sound (control treatment; the animals were only exposed to the experimental tank's background noise) and 10 days of noise derived from original recordings of motor boats, including recreational boats, hydrofoil, fishing boat and ferry boat (vessel noise treatment). The exposure to noise produced significant variations in almost all the plasma parameters assessed, but no differences were observed in weights and fork lengths. A PERMANOVA analysis highlighted significantly increased values (p pollutant. Finally, these experimental studies could represent part of the science that is able to improve the quality of the policies related to management plans for maritime spaces (Marine Strategy Framework Directive 56/2008 CE) that are aimed at stemming this pollutant phenomenon.

  10. The influence of sex hormones on seizures in dogs and humans.

    Science.gov (United States)

    Van Meervenne, Sofie A E; Volk, Holger A; Matiasek, Kaspar; Van Ham, Luc M L

    2014-07-01

    Epilepsy is the most common chronic neurological disorder in both humans and dogs. The effect of sex hormones on seizures is well documented in human medicine. Catamenial epilepsy is defined as an increase in frequency and severity of seizures during certain periods of the menstrual cycle. Oestradiol increases seizure activity and progesterone is believed to exhibit a protective effect. The role of androgens is controversial and there is a lack of research focusing on androgens and epilepsy. Indeed, little is known about the influence of sex hormones on epilepsy in dogs. Sterilisation is believed to improve seizure control, but no systematic research has been conducted in this field. This review provides an overview of the current literature on the influence of sex hormones on seizures in humans. The literature on idiopathic epilepsy in dogs was assessed to identify potential risk factors related to sex and sterilisation status. In general, there appears to be an over-representation of male dogs with idiopathic epilepsy but no explanation for this difference in prevalence between sexes has been reported. In addition, no reliable conclusions can be drawn on the effect of sterilisation due to the lack of focused research and robust scientific evidence.

  11. Critical Factors Influencing Decision to Adopt Human Resource Information System (HRIS) in Hospitals.

    Science.gov (United States)

    Alam, Md Golam Rabiul; Masum, Abdul Kadar Muhammad; Beh, Loo-See; Hong, Choong Seon

    2016-01-01

    The aim of this research is to explore factors influencing the management decisions to adopt human resource information system (HRIS) in the hospital industry of Bangladesh-an emerging developing country. To understand this issue, this paper integrates two prominent adoption theories-Human-Organization-Technology fit (HOT-fit) model and Technology-Organization-Environment (TOE) framework. Thirteen factors under four dimensions were investigated to explore their influence on HRIS adoption decisions in hospitals. Employing non-probability sampling method, a total of 550 copies of structured questionnaires were distributed among HR executives of 92 private hospitals in Bangladesh. Among the respondents, usable questionnaires were 383 that suggesting a valid response rate of 69.63%. We classify the sample into 3 core groups based on the HRIS initial implementation, namely adopters, prospectors, and laggards. The obtained results specify 5 most critical factors i.e. IT infrastructure, top management support, IT capabilities of staff, perceived cost, and competitive pressure. Moreover, the most significant dimension is technological dimension followed by organisational, human, and environmental among the proposed 4 dimensions. Lastly, the study found existence of significant differences in all factors across different adopting groups. The study results also expose constructive proposals to researchers, hospitals, and the government to enhance the likelihood of adopting HRIS. The present study has important implications in understanding HRIS implementation in developing countries.

  12. 离散频谱分析比值校正法幅值和相位的抗噪性分析%Noise influence on amplitude and phase estimation accuracy by interpolation method for discrete spectrum

    Institute of Scientific and Technical Information of China (English)

    徐传燕; 丁康; 林慧斌; 杨志坚

    2011-01-01

    谐波信号离散频谱分析的比值校正法(内插法)在无噪声时是一种准确的校正方法,只存在计算时的舍入误差,但在包含噪声尤其信噪比较低时,校正精度会有所下降,甚至误差很大.研究了比值校正法的幅值与相位加不同的窗函数及加性高斯白噪声时的统计方差公式,并通过不同信噪比下的仿真验证了其准确性.建议避免在归一化频率误差较低的情况下使用加矩形窗的比值校正法来校正相位.%Without noise, Interpolation method for discrete spectrum is an accurate correction method except rounding errors. However, the estimation accuracy can be greatly reduced when a signal corrupted with noise, and even turns out to be meaningless. The paper investigates the influences of windowing and additive White Gaussian Noise on the accuracy of amplitude and phase based on interpolation method. Analytical expressions of the estimator variance for amplitude and phase correction are derived. Simulation results confirm the validity of the presented analysis. We suggest to avoid using interpolation method under the condition that the rectangular window is adopted to correct the phase when the normalization frequency error is small.

  13. Phylogenetic perspectives on noise-induced fear and annoyance

    Science.gov (United States)

    Bowles, Ann

    2003-04-01

    Negative human responses to noise are typically interpreted in terms of human psychological, cognitive, or social processes. However, it may be useful to frame hypotheses about human responses in terms of evolutionary history, during which negative responses have been part of a suite of adaptions to a variable sound environment. By comparing the responses of a range of nonhuman animals to various types of noise, it is possible to develop hypotheses about the ecology of human responses. Examples of noise-related phenomena that could be explained usefully from this perspective include the Schulz curve, noise-induced physical stress, acute fear responses induced by transient noise, and the relationship between temperament and noise-induced annoyance. Responses of animals from a range of taxa will be described and their behavior interpreted in terms of their life-history strategies. With this perspective, some testable hypotheses about noise-induced fear and annoyance will be suggested.

  14. PARP-1 inhibition influences the oxidative stress response of the human lens

    Directory of Open Access Journals (Sweden)

    Andrew J.O. Smith

    2016-08-01

    Full Text Available Poly(ADP-ribose polymerase-1 (PARP-1 is best characterised for its involvement in DNA repair. PARP-1 activity is also linked to cell fate, confounding its roles in maintaining genome integrity. The current study assessed the functional roles of PARP-1 within human lens cells in response to oxidative stress. The human lens epithelial cell line FHL124 and whole human lens cultures were used as experimental systems. Hydrogen peroxide (H2O2 was employed to induce oxidative stress and cell death was assessed by LDH release. The functional influence of PARP-1 was assessed using targeted siRNA and chemical inhibition (by AG14361. Immunocytochemistry and western blotting were used to assess PARP-1 expression and the alkaline comet assay determined the levels of DNA strand breaks. PARP-1 was generally observed in the cell nucleus in both the FHL124 cell line and whole human lenses. PARP-1 inhibition rendered FHL124 cells more susceptible to H2O2-induced DNA strand breaks. Interestingly, reduction of PARP-1 activity significantly inhibited H2O2-induced cell death relative to control cells. Inhibition of PARP-1 in whole human lenses resulted in a reduced level of lens opacity and cell death following exposure to H2O2 relative to matched pair controls. Thus, we show that PARP-1 could play a role in the fate of human lens cells, and these first observations in human lenses suggest that it could impact on lens opacity. Further studies are required to elucidate the regulatory processes that give rise to these effects.

  15. Humans (really) are animals: picture-book reading influences 5-year-old urban children's construal of the relation between humans and non-human animals.

    Science.gov (United States)

    Waxman, Sandra R; Herrmann, Patricia; Woodring, Jennie; Medin, Douglas L

    2014-01-01

    What is the relation between humans and non-human animals? From a biological perspective, we view humans as one species among many, but in the fables and films we create for children, we often offer an anthropocentric perspective, imbuing non-human animals with human-like characteristics. What are the consequences of these distinctly different perspectives on children's reasoning about the natural world? Some have argued that children universally begin with an anthropocentric perspective and that acquiring a biological perspective requires a basic conceptual change (cf. Carey, 1985). But recent work reveals that this anthropocentric perspective, evidenced in urban 5-year-olds, is not evident in 3-year-olds (Herrmann etal., 2010). This indicates that the anthropocentric perspective is not an obligatory first step in children's reasoning about biological phenomena. In the current paper, we introduced a priming manipulation to assess whether 5-year-olds' reasoning about a novel biological property is influenced by the perspectives they encounter in children's books. Just before participating in a reasoning task, each child read a book about bears with an experimenter. What varied was whether bears were depicted from an anthropomorphic (Berenstain Bears) or biological perspective (Animal Encyclopedia). The priming had a dramatic effect. Children reading the Berenstain Bears showed the standard anthropocentric reasoning pattern, but those reading the Animal Encyclopedia adopted a biological pattern. This offers evidence that urban 5-year-olds can adopt either a biological or a human-centered stance, depending upon the context. Thus, children's books and other media are double-edged swords. Media may (inadvertently) support human-centered reasoning in young children, but may also be instrumental in redirecting children's attention to a biological model.

  16. Humans (really) are animals: picture-book reading influences 5-year-old urban children’s construal of the relation between humans and non-human animals

    Science.gov (United States)

    Waxman, Sandra R.; Herrmann, Patricia; Woodring, Jennie; Medin, Douglas L.

    2014-01-01

    What is the relation between humans and non-human animals? From a biological perspective, we view humans as one species among many, but in the fables and films we create for children, we often offer an anthropocentric perspective, imbuing non-human animals with human-like characteristics. What are the consequences of these distinctly different perspectives on children’s reasoning about the natural world? Some have argued that children universally begin with an anthropocentric perspective and that acquiring a biological perspective requires a basic conceptual change (cf. Carey, 1985). But recent work reveals that this anthropocentric perspective, evidenced in urban 5-year-olds, is not evident in 3-year-olds (Herrmann etal., 2010). This indicates that the anthropocentric perspective is not an obligatory first step in children’s reasoning about biological phenomena. In the current paper, we introduced a priming manipulation to assess whether 5-year-olds’ reasoning about a novel biological property is influenced by the perspectives they encounter in children’s books. Just before participating in a reasoning task, each child read a book about bears with an experimenter. What varied was whether bears were depicted from an anthropomorphic (Berenstain Bears) or biological perspective (Animal Encyclopedia). The priming had a dramatic effect. Children reading the Berenstain Bears showed the standard anthropocentric reasoning pattern, but those reading the Animal Encyclopedia adopted a biological pattern. This offers evidence that urban 5-year-olds can adopt either a biological or a human-centered stance, depending upon the context. Thus, children’s books and other media are double-edged swords. Media may (inadvertently) support human-centered reasoning in young children, but may also be instrumental in redirecting children’s attention to a biological model. PMID:24672493

  17. Investigation of noise sources and propagation in external gear pumps

    Science.gov (United States)

    Opperwall, Timothy J.

    Oil hydraulics is widely accepted as the best technology for transmitting power in many engineering applications due to its advantages in power density, control, layout flexibility, and efficiency. Due to these advantages, hydraulic systems are present in many different applications including construction, agriculture, aerospace, automotive, forestry, medical, and manufacturing, just to identify a few. Many of these applications involve the systems in close proximity to human operators and passengers where noise is one of the main constraints to the acceptance and spread of this technology. As a key component in power transfer, displacement machines can be major sources of noise in hydraulic systems. Thus, investigation into the sources of noise and discovering strategies to reduce noise is a key part of applying fluid power systems to a wider range of applications, as well as improving the performance of current hydraulic systems. The present research aims to leverage previous efforts and develop new models and experimental techniques in the topic of noise generation caused by hydrostatic units. This requires challenging and surpassing current accepted methods in the understanding of noise in fluid power systems. This research seeks to expand on the previous experimental and modeling efforts by directly considering the effect that system and component design changes apply on the total sound power and the sound frequency components emitted from displacement machines and the attached lines. The case of external gear pumps is taken as reference for a new model to understand the generation and transmission of noise from the sources out to the environment. The lumped parameter model HYGESim (HYdraulic GEar machine Simulator) was expanded to investigate the dynamic forces on the solid bodies caused by the pump operation and to predict interactions with the attached system. Vibration and sound radiation were then predicted using a combined finite element and boundary

  18. How the Learning Path and the Very Structure of a Multifloored Environment Influence Human Spatial Memory.

    Science.gov (United States)

    Dollé, Laurent; Droulez, Jacques; Bennequin, Daniel; Berthoz, Alain; Thibault, Guillaume

    2015-01-01

    Few studies have explored how humans memorize landmarks in complex multifloored buildings. They have observed that participants memorize an environment either by floors or by vertical columns, influenced by the learning path. However, the influence of the building's actual structure is not yet known. In order to investigate this influence, we conducted an experiment using an object-in-place protocol in a cylindrical building to contrast with previous experiments which used rectilinear environments. Two groups of 15 participants were taken on a tour with a first person perspective through a virtual cylindrical three-floored building. They followed either a route discovering floors one at a time, or a route discovering columns (by simulated lifts across floors). They then underwent a series of trials, in which they viewed a camera movement reproducing either a segment of the learning path (familiar trials), or performing a shortcut relative to the learning trajectory (novel trials). We observed that regardless of the learning path, participants better memorized the building by floors, and only participants who had discovered the building by columns also memorized it by columns. This expands on previous results obtained in a rectilinear building, where the learning path favoured the memory of its horizontal and vertical layout. Taken together, these results suggest that both learning mode and an environment's structure influence the spatial memory of complex multifloored buildings.

  19. Influence of ventilation and hypocapnia on sympathetic nerve responses to hypoxia in normal humans.

    Science.gov (United States)

    Somers, V K; Mark, A L; Zavala, D C; Abboud, F M

    1989-11-01

    The sympathetic response to hypoxia depends on the interaction between chemoreceptor stimulation (CRS) and the associated hyperventilation. We studied this interaction by measuring sympathetic nerve activity (SNA) to muscle in 13 normal subjects, while breathing room air, 14% O2, 10% O2, and 10% O2 with added CO2 to maintain isocapnia. Minute ventilation (VE) and blood pressure (BP) increased significantly more during isocapnic hypoxia (IHO) than hypocapnic hypoxia (HHO). In contrast, SNA increased more during HHO [40 +/- 10% (SE)] than during IHO (25 +/- 19%, P less than 0.05). To determine the reason for the lesser increase in SNA with IHO, 11 subjects underwent voluntary apnea during HHO and IHO. Apnea potentiated the SNA responses to IHO more than to HHO. SNA responses to IHO were 17 +/- 7% during breathing and 173 +/- 47% during apnea whereas SNA responses to HHO were 35 +/- 8% during breathing and 126 +/- 28% during apnea. During ventilation, the sympathoexcitation of IHO (compared with HHO) is suppressed, possibly for two reasons: 1) because of the inhibitory influence of activation of pulmonary afferents as a result of a greater increase in VE, and 2) because of the inhibitory influence of baroreceptor activation due to a greater rise in BP. Thus in humans, the ventilatory response to chemoreceptor stimulation predominates and restrains the sympathetic response. The SNA response to chemoreceptor stimulation represents the net effect of the excitatory influence of the chemoreflex and the inhibitory influence of pulmonary afferents and baroreceptor afferents.

  20. Solar noise storms

    CERN Document Server

    Elgaroy, E O

    2013-01-01

    Solar Noise Storms examines the properties and features of solar noise storm phenomenon. The book also presents some theories that can be used to gain a better understanding of the phenomenon. The coverage of the text includes topics that cover the features and behavior of noise storms, such as the observable features of noise storms; the relationship between noise storms and the observable features on the sun; and ordered behavior of storm bursts in the time-frequency plane. The book also covers the spectrum, polarization, and directivity of noise storms. The text will be of great use to astr

  1. Sympathetic influence on cerebral blood flow and metabolism during exercise in humans

    DEFF Research Database (Denmark)

    Seifert, Thomas; Secher, Niels H

    2011-01-01

    -oxidative carbohydrate uptake during exercise. Adrenaline appears to accelerate cerebral glycolysis through a beta2-adrenergic receptor mechanism since noradrenaline is without such an effect. In addition, the exercise-induced cerebral non-oxidative carbohydrate uptake is blocked by combined beta 1/2-adrenergic blockade......, but not by beta1-adrenergic blockade. Furthermore, endurance training appears to lower the cerebral non-oxidative carbohydrate uptake and preserve cerebral oxygenation during submaximal exercise. This is possibly related to an attenuated catecholamine response. Finally, exercise promotes brain health as evidenced......This review focuses on the possibility that autonomic activity influences cerebral blood flow (CBF) and metabolism during exercise in humans. Apart from cerebral autoregulation, the arterial carbon dioxide tension, and neuronal activation, it may be that the autonomic nervous system influences CBF...

  2. The intent to exercise influences the cerebral O(2)/carbohydrate uptake ratio in humans

    DEFF Research Database (Denmark)

    Dalsgaard, Mads K; Ide, Kojiro; Cai, Yan

    2002-01-01

    During and after maximal exercise there is a 15-30 % decrease in the metabolic uptake ratio (O(2)/[glucose + 1/2 lactate]) and a net lactate uptake by the human brain. This study evaluated if this cerebral metabolic uptake ratio is influenced by the intent to exercise, and whether a change could......, the a-v difference for the amino acids and glycerol did not change significantly, and there was only a minimal increase in the a-v difference for free fatty acids after maximal exercise. After maximal exercise the metabolic uptake ratio of the brain decreased from 6.1 +/- 0.5 (mean +/- S.E.M.) at rest.......2) in the early recovery (n = 10; P brain are increased out of proportion to O(2) when the brain is activated by exhaustive exercise, and that such metabolic changes are influenced by the will to exercise. We speculate that the uptake ratio...

  3. [Optimally control urban railway noise by sound propagation path].

    Science.gov (United States)

    Di, Guo-qing; Li, Zheng-guang; Chen, Yu; Zhang, Bang-jun

    2008-08-01

    In order to control railway noise pollution in urban areas, the residential district located near the Zhegan railway in Hangzhou urban was taken for example, and some controlling measures were proposed based on the investigation in railway noise impact as well as the planning of the district, the environmental scene and the project devises. The measures included setting man-made soil slopes, noise barriers and virescence. Combining some of them could be a typical noise reduction scheme. The professional software Cadna/A was used to predict the noise reduction results of every scheme. Results show that the maximal difference of noise reduction is 19.4 dB and the noise reduction effect of the second scheme is best. However, if only railway noise influence is considered, the first scheme is best. The research results can provide reference for residential districts planning and noise control near the railway in urban areas.

  4. Ranking of Reactions Based on Sensitivity of Protein Noise Depends on the Choice of Noise Measure.

    Directory of Open Access Journals (Sweden)

    Sucheta Gokhale

    Full Text Available Gene expression is a stochastic process. Identification of the step maximally affecting noise in the protein level is an important aspect of investigation of gene product distribution. There are numerous experimental and theoretical studies that seek to identify this important step. However, these studies have used two different measures of noise, viz. coefficient of variation and Fano factor, and have compared different processes leading to contradictory observations regarding the important step. In this study, we performed systematic global and local sensitivity analysis on two models of gene expression to investigate relative contribution of reaction rate parameters to steady state noise in the protein level using both the measures of noise. We analytically and computationally showed that the ranking of parameters based on the sensitivity of the noise to variation in a given parameter is a strong function of the choice of the noise measure. If the Fano factor is used as the noise measure, translation is the important step whereas for coefficient of variation, transcription is the important step. We derived an analytical expression for local sensitivity and used it to explain the distinct contributions of each reaction parameter to the two measures of noise. We extended the analysis to a generic linear catalysis reaction system and observed that the reaction network topology was an important factor influencing the local sensitivity of the two measures of noise. Our study suggested that, for the analysis of contributions of reactions to the noise, consideration of both the measures of noise is important.

  5. Noise controlled pattern for- mation in subexcitable media

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The numerical simulation on a reaction-diffu- sion system indicates that different patterns can be obtained by tuning the strength of parameter noise in subexcitable media. With the increase of noise intensity, the waves sustained by noise are not broken up as usual, they evolve orderly, and the period of the waves decreases, the survival time of waves varies. The time interval of inputting noise also influences the process of pattern formation and the survival time of waves.

  6. Probabilistic assessment of the influence of lake properties in long-term radiation doses to humans.

    Science.gov (United States)

    Pohjola, Jari; Turunen, Jari; Lipping, Tarmo; Ikonen, Ari T K

    2016-11-01

    The assessment processes concerning the safety of nuclear waste repositories include the modelling of radionuclide transport in biosphere and the evaluation of the doses to the most affected humans. In this paper, a scenario, in which a contaminated lake is the water source for drinking water, irrigation water and watering of livestock, is presented. The objective of the paper is to probabilistically study the influence of lake properties as parameters in the assessment scenario. The properties of the lake are a result of previously conducted probabilistic studies, where the land uplift of the terrain surrounding the repositories and the formation of water bodies were studied in a 10,000-year time span using Monte Carlo simulation. The lake is formed at 3000 years from present day and the changing properties of the lake have been used in the study. The studied radionuclides (36)Cl, (135)Cs, (129)I, (237)Np, (90)Sr, (99)Tc and (238)U enter the lake with a rate of 1 Bq/year. The transport process from the lake water to humans is described and the doses (dose conversion factors) to adult humans are evaluated based on a study on average food consumption. Sensitivity analysis is used for identifying the parameters having the most influence on the outcome of the dose. Based on the results from the sensitivity analysis, the volumetric outflow rate of the lake and the volume of the lake were taken into closer consideration. The results show the influence of probabilistically derived geomorphic lake input parameters on the dose. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Platelet serotonin transporter (5HTt): physiological influences on kinetic characteristics in a large human population.

    Science.gov (United States)

    Banović, Miroslav; Bordukalo-Niksić, Tatjana; Balija, Melita; Cicin-Sain, Lipa; Jernej, Branimir

    2010-01-01

    The present study had two goals: first, to give a detailed description of a reliable method for full kinetic analysis of serotonin transporter (5HTt) on the membrane of human platelets, and second, as a main issue, to report on physiological influences on kinetic characteristics of this transmembrane transport on a large population of healthy individuals. Full kinetic analyses of platelet serotonin uptake were performed on 334 blood donors of both sexes by the use of 14C-radioisotopic method, which was first optimized according to assumptions of enzyme kinetic analyses, with regard to platelet concentration, duration of uptake, concentration of substrate as well as important technical parameters (underpressure of filtration, blanks, incubating temperature, etc). Kinetic parameters of platelet serotonin uptake in the whole population were for V(max): 142 +/- 25.3 pmol 5HT/10(8) platelets/minute and for K(m): 0.404 +/- 0.089 microM 5HT. Besides the report on kinetic values of 5HT transporter protein, we have also described major physiological influences on the mentioned parameters, V(max), K(m) and their derivative, V(max)/K(m) (transporter efficiency): range and frequency distribution of normal values, intraindividual stability over time, lack of age influence, gender dependence and seasonal variations. The report on kinetic values and main physiological influences on platelet serotonin transport kinetics, obtained by the use of thoroughly reassessed methodology, and on by far the largest human population studied until now, offers a reliable frame of reference for pathophysiological studies of this parameter in various clinical fields.

  8. Noise Estimation and Noise Removal Techniques for Speech Recognition in Adverse Environment

    OpenAIRE

    Shrawankar, Urmila; Thakare, Vilas

    2010-01-01

    International audience; Noise is ubiquitous in almost all acoustic environments. The speech signal, that is recorded by a microphone is generally infected by noise originating from various sources. Such contamination can change the characteristics of the speech signals and degrade the speech quality and intelligibility, thereby causing significant harm to human-to-machine communication systems. Noise detection and reduction for speech applications is often formulated as a digital filtering pr...

  9. Reaggregation of human, chick, and human embryonic brain cells. Factors influencing the formation of a histiotypic unit.

    Science.gov (United States)

    Lodin, Z; Fleischmannová, V; Hájková, B; Faltin, J; Hartman, J

    1981-01-01

    1. Aggregation of embryo human, mouse, and chick brain cells was studied. The optimum age interval of donors from different species was determined. 2. The significance of different dissociation procedures (mild trypsinisation followed by sieving, trypsinisation + DNA digestion, mechanical dissociation in 1 or 2 steps, and Ca2+ chelation by EGTA) for the rate of aggregation was estimated. A significant reduction of aggregation was observed after one step mechanical dissociation. Nonspecific adhesion of cells on DNA molecules was found only during the first stages of aggregation. 3. The curve of aggregation kinetics follows the curve of floculation kinetics. 90% free cells disappear from the medium after 2 h of aggregation and a large number of microaggregates are formed which condense after 20 to 24 h into compact aggregates. The time course of aggregation was similar for all cells dissociated by different means. Small differences in the rate of aggregation, caused by dissociation procedures, were apparent only during the first stages of aggregation. 4. The histiotypic unit formed by aggregation of human, mouse, and chick embryo brain cells exhibits some common and some specific features. During aggregation a multiple structural reconstruction takes place and a limited number of cells are exchanged or sorted out from aggregates into the medium. 5. The structural organisation of aggregates from differently dissociated cells differs in several aspects. This indicates that membrane surface structures are influenced differently by dissociation and behave differently during distinct stages of aggregation.

  10. The influence of culture on human resource management processes and practices: The propositions for Serbia

    Directory of Open Access Journals (Sweden)

    Bogićević-Milikić Biljana

    2009-01-01

    Full Text Available This paper attempts to address the influence of national culture on HRM practices and processes in order to draw conclusions for Serbian HR practitioners, multinational corporations operating in Serbia, and any other country or organizational context that has similar cultural characteristics. To achieve this we first review the relevant literature to identify the interdependencies between Hofstede's cultural dimensions and HRM practices and processes. On the basis of recognized relationships we put forward 11 propositions about likely appropriate HRM practices (such as job analysis, recruitment and selection, human resource planning and career management for the Serbian cultural context, characterized by high Uncertainty Avoidance, high Power Distance, Collectivism and Femininity.

  11. An essay concerning human understanding: how the cerebri anatome of Thomas Willis influenced John Locke.

    Science.gov (United States)

    Lega, Bradley C

    2006-03-01

    Neurosurgeons are familiar with the anatomic investigations of Thomas Willis, but his intellectual legacy actually extends into the arena of philosophy. John Locke was a student of Willis while at Oxford, and this essay explores how some of Willis's anatomic discoveries might have influenced the ideas Locke expressed in his Essay Concerning Human Understanding. It also includes historical information about 17th century England and the group of men (including Christopher Wren and Robert Boyle) who worked with Willis and founded the Oxford Experimental Philosophy Club, which became the Royal Society.

  12. Influence of nimodipine, verapamil and lanthanum on histamine release from human basophils

    DEFF Research Database (Denmark)

    Jensen, C B; Thastrup, Ole; Norn, S;

    1987-01-01

    Our previous studies suggest that the membrane content of sialic acid influences histamine release from human basophils by interfering with the transmembraneous calcium fluxes preceding histamine release. In this study we investigated a possible interaction between membrane sialic acid...... and the calcium channels, using the calcium antagonists nimodipine, verapamil and lanthanum. Anti-IgE-induced histamine release was inhibited by verapamil, nimodipine and lanthanum. When cells were pretreated with sialidase in order to remove sialic acid from the cell membrane, the inhibitory action of nimodipine...

  13. Helicopter Noise And Noise Abatement Procedures

    Directory of Open Access Journals (Sweden)

    Borivoj Galović

    2004-03-01

    Full Text Available The helicopter generated noise at and around the airports islower than the noise generated by aeroplanes, since their numberof operations, i. e. the number of takeoffs and landings ismuch lower than the takeoffs and landings of the aeroplanes.Out of some hundred operations a day, helicopters participatewith approximately 15%, but the very impact of noise is by nomeans negligible, since the number of helicopter flights aboveurban areas is constantly increasing.This paper attempts to analyse this phenomenon and thetype of helicopter generated noise, its negative impacts, to explainthe flight procedures and the operative procedures duringtakeoff, landing and overflight of helicopters in operations inthe vicinity and outside airports, as well as the methods of measuringand determining the limit of noise [eve~ and the resultingproblems.

  14. Influences of dibutyryl cyclic adenosine monophosphate and forskolin on human sperm motility in vitro

    Institute of Scientific and Technical Information of China (English)

    Ji-HongLIU; YangLI; Zheng-GuoCAO; Zhang-QunYE

    2003-01-01

    Aim: To study the influences of dibutyryl cyclic adenosine monophosphate (dbcAMP) and forskolin on human sperm motility in vitro. Methods: Semen samples, aseptically obtained by masturbation and prepared by swim-up technique from 20 fertile men, were incubated with different concenlrations of dbcAMP and forskolin at 37℃. Measurements were carried out after l0 min, 20 min, 30 min and 60 min incubation. Motility parameters were estimated by using an automatic analyzing system. Results: Treatment with dbcAMP or forskolin resulted in a significant increase in sperm motility and progressive motility. The larger the concenlrations of dbcAMP or forskolin,the greater the effect appeared. The straight linear velocity and curvilinear velocity were not affected by both agents.Conclusion: dbcAMP and forskolin increase the motility and progressive motility of human sperm in vitro. ( Asian J Androl 2003 Jun; 5: 113-115)

  15. [Influence of Storage Temperature and Cryopreservation Conditions on the Extent of Human Sperm DNA Fragmentation].

    Science.gov (United States)

    Simonenko, E Yu; Garmaeva, S B; Yakovenko, S A; Grigorieva, A A; Tverdislov, V A; Mironova, A G; Aprishko, V P

    2016-01-01

    With the direct labeling procedure for detecting DNA fragmentation we explored the influence of the different storage temperature conditions as well as different methods of cryopreservation on the structure of DNA organization in the human sperm. 19 sperm samples obtained from healthy men with normozoospermia (according to the criteria of the World Health Organization) were used for investigation. A significant increase of human sperm DNA-fragmentation was observed after 8 hours of incubation at +39 degrees C (by 76.7%) and at +37 degrees C (by 68.9%). It was found that sperm cooling with the use of a cryoprotectant immediately after thawing did not produce significant differences in the extent of DNA fragmentation, although samples, containing cryoprotectants, showed a sharp increase of DNA fragmentation after 24 hours of incubation, that could suggest cryoprotectant cytotoxicity.

  16. On Noise Generation and Dynamic Transmission Error of Gears

    OpenAIRE

    Henriksson, Mats

    2009-01-01

    Noise from heavy trucks is an important environmental issue. Several sources contribute to the total noise level of a vehicle, such as the engine, gearbox, tires, etc. The tonal noise from the gearbox can be very disturbing for the driver, even if the noise level from the gearbox is lower than the total noise level. The human ear has a remarkable way of detecting pure tones of which the noise from loaded gears consists of. To be allowed to sell a heavy truck within the European Union, the so ...

  17. 推力轴承基座对艇体振动及其辐射噪声的影响%Influence of Thrust Bearing Pedestal Form on Vibration and Radiated Noise of Submarine

    Institute of Scientific and Technical Information of China (English)

    丁科; 王永生; 魏应三

    2013-01-01

    FEM/BEM method is used to calculate the structure vibration and underwater radiated noise of the single-shell submarine which is full-scale caused by the propeller fluctuating thrust force. The influence of vibration and radiated noise caused by the propeller of the two kinds thrust bearing pedestal forms (flanged thrust bearing pedestal and common pedestal) is analysed and com-pared. The study shows that the flanged thrust bearing pedestal can reduce the underwater radiated noise up to 25 dB in frequency region except around 28 Hz. The common pedestal is combined with the submarine hull, it causes the longitudinal vibration and the lateral vibration, and the normal vi-bration is much stronger; but the flanged thrust bearing pedestal transfers the propeller fluctuating force equally to the submarine hull along the circumference, it mainly causes longitudinal vibration, only the head and tail of the hull cause normal vibration, and so the noise level is lower.%  利用FEM/BEM方法计算了实尺度单壳体潜艇在螺旋桨激振力作用下的结构振动和水下声辐射特性。分析比较了两种推力轴承基座形式(法兰盘式基座和普通基座)对潜艇在螺旋桨激励下振动与噪声性能的影响。结果表明,安装法兰盘式推力轴承基座能在除28 Hz附近降低潜艇辐射噪声,最大降低25 dB左右。普通推力轴承基座形式只将螺旋桨脉动推力加载到与其相连的艇体结构上,引起纵向振动和横向振动,其壳体的法向振动较强烈;而法兰盘式推力轴承基座可以将螺旋桨脉动推力沿周向均匀地加载到艇体上,它主要引起纵向振动,只有艇体首尾处有法向振动,因而,噪声较低。

  18. The influence of body posture on the kinematics of prehension in humans and gorillas (Gorilla gorilla).

    Science.gov (United States)

    Reghem, E; Chèze, L; Coppens, Y; Pouydebat, E

    2014-03-01

    Much of our current understanding of human prehension in a comparative context is based on macaque models in a sitting, constrained body posture. In a previous study, we clearly showed differences in the amplitude of the forelimb joints between five primate species (lemur, capuchin, chimpanzee, gorilla and human) during unconstrained grasping where the animals were free to choose their body posture. One of our interrogations was to know if these differences could be due to the body posture. To address this question, this study compares humans with new data for gorillas during an unconstrained food prehension task in two body postures, a sitting and a quadrupedal one. The objective is to determine the behavioral and kinematic strategies (amplitudes and patterns of evolution of the articular angles) as well as differences and invariants of trunk and forelimb motions between species. The subjects were recorded by five cameras, and landmarks were digitized frame by frame to reconstruct 3D movement. Our results show that (1) despite significant influences of body postures on ranges of motion in gorillas and humans, species preserve their specific forelimb joint and trunk contribution; (2) body posture has a limited effect on the basic pattern of wrist velocity. Our study indicates that different primate species have specific kinematic features of limb coordination during prehension, which dose not alter with changes in posture. Therefore, across varying species, it is possible to compare limb kinematics irrespective of postural constraints and unconstrained condition need to be explored in other primates to understand the evolution of primate prehension.

  19. Variation at genes influencing facial morphology are not associated with developmental imprecision in human faces.

    Directory of Open Access Journals (Sweden)

    Sonja Windhager

    Full Text Available Facial asymmetries are commonly used as a proxy for human developmental imprecision resulting from inbreeding, and thus reduced genetic heterozygosity. Several environmental factors influence human facial asymmetry (e.g., health care, parasites, but the generalizability of findings on genetic stressors has been limited in humans by sample characteristics (island populations, endogamy and indirect genetic assessment (inference from pedigrees. In a sample of 3215 adult humans from the Rotterdam Study, we therefore studied the relationship of facial asymmetry, estimated from nine mid-facial landmarks, with genetic variation at 102 single nucleotide polymorphism (SNP loci recently associated with facial shape variation. We further tested whether the degree of individual heterozygosity is negatively correlated with facial asymmetry. An ANOVA tree regression did not identify any SNP relating to either fluctuating asymmetry or total asymmetry. In a general linear model, only age and sex--but neither heterozygosity nor any SNP previously reported to covary with facial shape--was significantly related to total or fluctuating asymmetry of the midface. Our study does not corroborate the common assumption in evolutionary and behavioral biology that morphological asymmetries reflect heterozygosity. Our results, however, may be affected by a relatively small degree of inbreeding, a relatively stable environment, and an advanced age in the Rotterdam sample. Further large-scale genetic studies, including gene expression studies, are necessary to validate the genetic and developmental origin of morphological asymmetries.

  20. Sex, Body Mass Index, and Dietary Fiber Intake Influence the Human Gut Microbiome

    Science.gov (United States)

    Dominianni, Christine; Sinha, Rashmi; Goedert, James J.; Pei, Zhiheng; Yang, Liying; Hayes, Richard B.; Ahn, Jiyoung

    2015-01-01

    Increasing evidence suggests that the composition of the human gut microbiome is important in the etiology of human diseases; however, the personal factors that influence the gut microbiome composition are poorly characterized. Animal models point to sex hormone-related differentials in microbiome composition. In this study, we investigated the relationship of sex, body mass index (BMI) and dietary fiber intake with the gut microbiome in 82 humans. We sequenced fecal 16S rRNA genes by 454 FLX technology, then clustered and classified the reads to microbial genomes using the QIIME pipeline. Relationships of sex, BMI, and fiber intake with overall gut microbiome composition and specific taxon abundances were assessed by permutational MANOVA and multivariate logistic regression, respectively. We found that sex was associated with the gut microbiome composition overall (p=0.001). The gut microbiome in women was characterized by a lower abundance of Bacteroidetes (p=0.03). BMI (>25 kg/m2 vs. Fiber from beans and from fruits and vegetables were associated, respectively, with greater abundance of Actinobacteria (p=0.006 and false discovery rate adjusted q=0.05) and Clostridia (p=0.009 and false discovery rate adjusted q=0.09). Our findings suggest that sex, BMI, and dietary fiber contribute to shaping the gut microbiome in humans. Better understanding of these relationships may have significant implications for gastrointestinal health and disease prevention. PMID:25874569

  1. Influence of the model's degree of freedom on human body dynamics identification.

    Science.gov (United States)

    Maita, Daichi; Venture, Gentiane

    2013-01-01

    In fields of sports and rehabilitation, opportunities of using motion analysis of the human body have dramatically increased. To analyze the motion dynamics, a number of subject specific parameters and measurements are required. For example the contact forces measurement and the inertial parameters of each segment of the human body are necessary to compute the joint torques. In this study, in order to perform accurate dynamic analysis we propose to identify the inertial parameters of the human body and to evaluate the influence of the model's number of degrees of freedom (DoF) on the results. We use a method to estimate the inertial parameters without torque sensor, using generalized coordinates of the base link, joint angles and external forces information. We consider a 34DoF model, a 58DoF model, as well as the case when the human is manipulating a tool (here a tennis racket). We compare the obtained in results in terms of contact force estimation.

  2. Ancient Humans Influenced the Current Spatial Genetic Structure of Common Walnut Populations in Asia.

    Directory of Open Access Journals (Sweden)

    Paola Pollegioni

    Full Text Available Common walnut (Juglans regia L is an economically important species cultivated worldwide for its wood and nuts. It is generally accepted that J. regia survived and grew spontaneously in almost completely isolated stands in its Asian native range after the Last Glacial Maximum. Despite its natural geographic isolation, J. regia evolved over many centuries under the influence of human management and exploitation. We evaluated the hypothesis that the current distribution of natural genetic resources of common walnut in Asia is, at least in part, the product of ancient anthropogenic dispersal, human cultural interactions, and afforestation. Genetic analysis combined with ethno-linguistic and historical data indicated that ancient trade routes such as the Persian Royal Road and Silk Road enabled long-distance dispersal of J. regia from Iran and Trans-Caucasus to Central Asia, and from Western to Eastern China. Ancient commerce also disrupted the local spatial genetic structure of autochthonous walnut populations between Tashkent and Samarkand (Central-Eastern Uzbekistan, where the northern and central routes of the Northern Silk Road converged. A significant association between ancient language phyla and the genetic structure of walnut populations is reported even after adjustment for geographic distances that could have affected both walnut gene flow and human commerce over the centuries. Beyond the economic importance of common walnut, our study delineates an alternative approach for understanding how the genetic resources of long-lived perennial tree species may be affected by the interaction of geography and human history.

  3. Vienna international airport noise abatement

    Directory of Open Access Journals (Sweden)

    Heidelinde Jelinek-Nigitz

    2016-03-01

    Full Text Available Purpose: On the topic of sustainable aviation a study was carried out to measure the difference between the actual change in air traffic noise and the airport’s residents’ perception of the noise change at Vienna International Airport. Therefore, a questionnaire was developed in cooperation with the airport and an online survey was conducted. Design/methodology/approach: For the survey of the opinion of the affected population of the surrounding communities, a web based online questionnaire is created and distributed via various channels including e-mail, and online forums. After the basic structure of the questionnaire had been defined, the questions were developed in cooperation with employees form the environmental department of VIE, who had a sustainable influence on the questions’ order and formulation. As the survey was supposed to be answered by residents around VIE. Findings: Results of the online study show that only parts of the participants are affected by air traffic noise at VIE. Even less experienced a significant change over the last five years. About one third of the participants stated that they are affected by air traffic noise in one way or another. The majority of these people live in Lower Austria, the federal state in which the airport is located. The participants obviously judge air traffic noise during day time more importantly than air traffic noise at night. Research limitations/implications: Due to the low number of returns, no statistically relevant conclusions can be drawn, the results of the survey can be used to make some general statements. Originality/value: Economic growth and deregulation lead to growing aircraft operations. Vienna International Airport with its approximately 260,000 flight movements per year is the biggest airport in Austria and a major hub in Europe. The combination of constantly growing air transport and the resulting noise exposure, as well as the steadily increasing

  4. Molecular evidence of host influences on the evolution and spread of human tapeworms.

    Science.gov (United States)

    Michelet, Lorraine; Dauga, Catherine

    2012-08-01

    The taeniasis/cysticercosis complex is included in the list of neglected zoonotic diseases by the World Health Organization due to its significant impact on public health in tropical areas. Cysticercosis is still endemic in many regions of Asia, Africa and Latin America. Long absent in Europe and in other developed countries, cysticercosis has recently re-emerged in the United States and Canada, due to immigration, travel and local transmission. This has encouraged the use of molecular data to understand better the influence of animal and human hosts on the emergence and spread of Taenia species. The increasing number of mitochondrial sequences now available from human tapeworms and recent advances in computational tools has enabled reconstruction of the biogeography and evolutionary history of these organisms. New molecular data have provided insights into the biogeography of T. solium, T. asiatica and T. saginata. A Bayesian statistical framework using variable evolutionary rates from lineage to lineage has allowed an improved timescale analysis of human tapeworms. The dates of divergence obtained were compared to the timing of evolutionary events in the history of their hosts, based on the hypothesis that Taenia spp. and their hosts share a common history. Herein, we review changes in the definitive and secondary hosts and human interactions that underlie the differentiation and evolution of tapeworms. Species diversification of Taenia seems to be closely linked with the evolution of intermediate hosts in response to climatic events during the Pleistocene. Different genotypes of T. solium emerged when European and Asian wild boar Sus spp. populations diverged. Taenia saginata emerged when wild cattle Bos primigenius evolved and when zebu Bos indicus and taurine Bos taurus ancestors separated. Humans through migrations and later with the development of farming and animal husbandry may have had a significant impact on the spread and diversification of tapeworms

  5. Longitudinal Study of Human Hearings: Its Relationship to Noise and Other Factors. 1. Design of Five Year Study; Data from First Year

    Science.gov (United States)

    1977-03-01

    that exposure to loud noises causes more histological damage in young than in adult guinea pigs (Jauhiainen et al., 1972) and that kittens lose more...particular care . Further, serial studies offer several advantages over cross-sectional studies. The major reasons why serial studies of auditory

  6. The Influence of Cochlear Mechanical Dysfunction, Temporal Processing Deficits, and Age on the Intelligibility of Audible Speech in Noise for Hearing-Impaired Listeners

    Directory of Open Access Journals (Sweden)

    Peter T. Johannesen

    2016-05-01

    Full Text Available The aim of this study was to assess the relative importance of cochlear mechanical dysfunction, temporal processing deficits, and age on the ability of hearing-impaired listeners to understand speech in noisy backgrounds. Sixty-eight listeners took part in the study. They were provided with linear, frequency-specific amplification to compensate for their audiometric losses, and intelligibility was assessed for speech-shaped noise (SSN and a time-reversed two-talker masker (R2TM. Behavioral estimates of cochlear gain loss and residual compression were available from a previous study and were used as indicators of cochlear mechanical dysfunction. Temporal processing abilities were assessed using frequency modulation detection thresholds. Age, audiometric thresholds, and the difference between audiometric threshold and cochlear gain loss were also included in the analyses. Stepwise multiple linear regression models were used to assess the relative importance of the various factors for intelligibility. Results showed that (a cochlear gain loss was unrelated to intelligibility, (b residual cochlear compression was related to intelligibility in SSN but not in a R2TM, (c temporal processing was strongly related to intelligibility in a R2TM and much less so in SSN, and (d age per se impaired intelligibility. In summary, all factors affected intelligibility, but their relative importance varied across maskers.

  7. The Influence of Cochlear Mechanical Dysfunction, Temporal Processing Deficits, and Age on the Intelligibility of Audible Speech in Noise for Hearing-Impaired Listeners

    Science.gov (United States)

    Johannesen, Peter T.; Pérez-González, Patricia; Kalluri, Sridhar; Blanco, José L.

    2016-01-01

    The aim of this study was to assess the relative importance of cochlear mechanical dysfunction, temporal processing deficits, and age on the ability of hearing-impaired listeners to understand speech in noisy backgrounds. Sixty-eight listeners took part in the study. They were provided with linear, frequency-specific amplification to compensate for their audiometric losses, and intelligibility was assessed for speech-shaped noise (SSN) and a time-reversed two-talker masker (R2TM). Behavioral estimates of cochlear gain loss and residual compression were available from a previous study and were used as indicators of cochlear mechanical dysfunction. Temporal processing abilities were assessed using frequency modulation detection thresholds. Age, audiometric thresholds, and the difference between audiometric threshold and cochlear gain loss were also included in the analyses. Stepwise multiple linear regression models were used to assess the relative importance of the various factors for intelligibility. Results showed that (a) cochlear gain loss was unrelated to intelligibility, (b) residual cochlear compression was related to intelligibility in SSN but not in a R2TM, (c) temporal processing was strongly related to intelligibility in a R2TM and much less so in SSN, and (d) age per se impaired intelligibility. In summary, all factors affected intelligibility, but their relative importance varied across maskers. PMID:27604779

  8. Noise Gating Solar Images

    Science.gov (United States)

    DeForest, Craig; Seaton, Daniel B.; Darnell, John A.

    2017-08-01

    I present and demonstrate a new, general purpose post-processing technique, "3D noise gating", that can reduce image noise by an order of magnitude or more without effective loss of spatial or temporal resolution in typical solar applications.Nearly all scientific images are, ultimately, limited by noise. Noise can be direct Poisson "shot noise" from photon counting effects, or introduced by other means such as detector read noise. Noise is typically represented as a random variable (perhaps with location- or image-dependent characteristics) that is sampled once per pixel or once per resolution element of an image sequence. Noise limits many aspects of image analysis, including photometry, spatiotemporal resolution, feature identification, morphology extraction, and background modeling and separation.Identifying and separating noise from image signal is difficult. The common practice of blurring in space and/or time works because most image "signal" is concentrated in the low Fourier components of an image, while noise is evenly distributed. Blurring in space and/or time attenuates the high spatial and temporal frequencies, reducing noise at the expense of also attenuating image detail. Noise-gating exploits the same property -- "coherence" -- that we use to identify features in images, to separate image features from noise.Processing image sequences through 3-D noise gating results in spectacular (more than 10x) improvements in signal-to-noise ratio, while not blurring bright, resolved features in either space or time. This improves most types of image analysis, including feature identification, time sequence extraction, absolute and relative photometry (including differential emission measure analysis), feature tracking, computer vision, correlation tracking, background modeling, cross-scale analysis, visual display/presentation, and image compression.I will introduce noise gating, describe the method, and show examples from several instruments (including SDO

  9. Influence of object location in different FOVs on trabecular bone microstructure measurements of human mandible: a cone beam CT study

    NARCIS (Netherlands)

    Ibrahim, N.; Parsa, A.; Hassan, B.; van der Stelt, P.; Aartman, I.H.A.; Nambiar, P.

    2014-01-01

    The aim of this study was to assess the influence of different object locations in different fields of view (FOVs) of two cone beam CT (CBCT) systems on trabecular bone microstructure measurements of a human mandible. A block of dry human mandible was scanned at five different locations (centre,

  10. Influence of object location in different FOVs on trabecular bone microstructure measurements of human mandible: a cone beam CT study

    NARCIS (Netherlands)

    Ibrahim, N.; Parsa, A.; Hassan, B.; van der Stelt, P.; Aartman, I.H.A.; Nambiar, P.

    2014-01-01

    The aim of this study was to assess the influence of different object locations in different fields of view (FOVs) of two cone beam CT (CBCT) systems on trabecular bone microstructure measurements of a human mandible. A block of dry human mandible was scanned at five different locations (centre, lef

  11. Noise-Measuring Method

    DEFF Research Database (Denmark)

    Diamond, J. M.

    1965-01-01

    A noise-measuring method based on the use of a calibrated noise generator and an output meter with a special scale is described. The method eliminates the effect of noise contributions occurring in the circuits following the device under test....

  12. Determination of the chemical composition of human renal stones with MDCT: influence of the surrounding media

    Science.gov (United States)

    Grosjean, Romain; Sauer, Benoît; Guerra, Rui; Kermarrec, Isabelle; Ponvianne, Yannick; Winninger, Daniel; Daudon, Michel; Blum, Alain; Felblinger, Jacques; Hubert, Jacques

    2007-03-01

    The selection of the optimal treatment method for urinary stones diseases depends on the chemical composition of the stone and its corresponding fragility. MDCT has become the most used modality to determine rapidly and accurately the presence of stones when evaluating urinary lithiasis treatment. That is why several studies have tempted to determine the chemical composition of the stones based on the stone X-ray attenuation in-vitro and invivo. However, in-vitro studies did not reproduce the normal abdominal wall and fat, making uncertain the standardization of the obtained values. The aim of this study is to obtain X-ray attenuation values (in Hounsfield Units) of the six more frequent types of human renal stones (n=217) and to analyze the influence of the surrounding media on these values. The stones were first placed in a jelly, which X-ray attenuation is similar to that of the human kidney (30 HU at 120 kV). They were then stuck on a grid, scanned in a water tank and finally scanned in the air. Significant differences in CT-attenuation values were obtained with the three different surrounding media (jelly, water, air). Furthermore there was an influence of the surrounding media and consequently discrepancies in determination of the chemical composition of the renal stones. Consequently, CT-attenuation values found in in-vitro studies cannot really be considered as a reference for the determination of the chemical composition except if the used phantom is an anthropomorphic one.

  13. Mouse models for studying genetic influences on factors determining smoking cessation success in humans

    Science.gov (United States)

    Hall, F. Scott; Markou, Athina; Levin, Edward D.; Uhl, George R.

    2014-01-01

    Humans differ in their ability to quit using addictive substances, including nicotine, the major psychoactive ingredient in tobacco. For tobacco smoking, a substantial body of evidence, largely derived from twin studies, indicates that approximately half of these individual differences in ability to quit are heritable [1, 2], genetic influences that likely overlap with those for other addictive substances [3]. Both twin and molecular genetic studies support overlapping influences on nicotine addiction vulnerability and smoking cessation success, although there is little formal analysis of the twin data that supports this important point [2, 3]. None of the current datasets provides clear data concerning which heritable factors might provide robust dimensions around which individuals differ in ability to quit smoking. One approach to this problem is to test mice with genetic variations in genes that contain human variants that alter quit-success. This review considers which features of quit success should be included in a comprehensive approach to elucidating the genetics of quit success, and how those features may be modeled in mice. PMID:22304675

  14. Observational Quantification of Climatic and Human Influences on Vegetation Greening in China

    Directory of Open Access Journals (Sweden)

    Wenjian Hua

    2017-04-01

    Full Text Available This study attempts to quantify the relative contributions of vegetation greening in China due to climatic and human influences from multiple observational datasets. Satellite measured vegetation greenness, Normalized Difference Vegetation Index (NDVI, and relevant climate, land cover, and socioeconomic data since 1982 are analyzed using a multiple linear regression (MLR method. A statistically significant positive trend of average growing-season (April–October NDVI is found over more than 34% of the vegetated areas, mainly in North China, while significant decreases in NDVI are only seen in less than 5% of the areas. The relationships between vegetation and climate (temperature, precipitation, and radiation vary by geographical location and vegetation type. We estimate the NDVI changes in association with the non-climatic effects by removing the climatic effects from the original NDVI time series using the MLR analysis. Our results indicate that land use change is the dominant factor driving the long-term changes in vegetation greenness. The significant greening in North China is due to the increase in crops, grasslands, and forests. The socioeconomic datasets provide consistent and supportive results for the non-climatic effects at the provincial level that afforestation and reduced fire events generally have a major contribution. This study provides a basis for quantifying the non-climatic effects due to possible human influences on the vegetation greening in China.

  15. Factors influencing recombination frequency and distribution in a human meiotic crossover hotspot.

    Science.gov (United States)

    Jeffreys, Alec J; Neumann, Rita

    2005-08-01

    Little is known about the factors that influence the frequency and distribution of meiotic recombination events within human crossover hotspots. We now describe the detailed analysis of sperm recombination in the NID1 hotspot. Like the neighbouring MS32 hotspot, the NID1 hotspot is associated with a minisatellite, suggesting that hotspots predispose DNA to tandem repetition. Unlike MS32, crossover resolution breakpoints in NID1 avoid the minisatellite, producing a cold spot within the hotspot. This avoidance may be related to the palindromic nature of the minisatellite interfering with the generation and/or processing of recombination intermediates. The NID1 hotspot also contains a single nucleotide polymorphism (SNP) close to the centre, which appears to directly influence the frequency of crossover initiation. Quantitative gene conversion assays show that this SNP affects the frequency of gene conversion and crossover to a very similar extent, providing evidence that conversions and crossovers are triggered by the same recombination initiating events. The recombination-suppressing allele is over-transmitted to recombinant progeny, and provides the most dramatic example to date of recombination-mediated meiotic drive, of a magnitude sufficient to virtually guarantee that the recombination suppressor will eventually replace the more active allele in human populations.

  16. A study on human serum albumin influence on glycation of fibrinogen

    Energy Technology Data Exchange (ETDEWEB)

    Kielmas, Martyna; Szewczuk, Zbigniew; Stefanowicz, Piotr, E-mail: Piotr.stefanowicz@chem.uni.wroc.pl

    2013-09-13

    Highlights: •The glycation of fibrinogen was investigated by isotopic labeling method. •The potential glycation sites in fibrinogen were identified. •Human serum albumin (HSA) inhibits the glycation of fibrinogen. •The effect of HSA on fibrinogen glycation is sequence-dependent. -- Abstract: Although in vivo glycation proceeds in complex mixture of proteins, previous studies did not take in consideration the influence of protein–protein interaction on Maillard reaction. The aim of our study was to test the influence of human serum albumin (HSA) on glycation of fibrinogen. The isotopic labeling using [{sup 13}C{sub 6}] glucose combined with LC-MS were applied as tool for identification possible glycation sites in fibrinogen and for evaluation the effect of HSA on the glycation level of selected amino acids in fibrinogen. The obtained data indicate that the addition of HSA protects the fibrinogen from glycation. The level of glycation in presence of HSA is reduced by 30–60% and depends on the location of glycated residue in sequence of protein.

  17. Literature survey on how different factors influence human comfort in indoor environments

    DEFF Research Database (Denmark)

    Frontczak, Monika Joanna; Wargocki, Pawel

    2011-01-01

    The present paper shows the results of a literature survey aimed at exploring how the indoor environment in buildings affects human comfort. The survey was made to gather data that can be useful when new concepts of controlling the indoor environment are developed. The following indoor environmen......The present paper shows the results of a literature survey aimed at exploring how the indoor environment in buildings affects human comfort. The survey was made to gather data that can be useful when new concepts of controlling the indoor environment are developed. The following indoor...... environmental conditions influencing comfort in the built environment were surveyed: thermal, visual and acoustic, as well as air quality. The literature was surveyed to determine which of these conditions were ranked by building users as being the most important determinants of comfort. The survey also...... examined the extent to which other factors unrelated to the indoor environment, such as individual characteristics of building occupants, building-related factors and outdoor climate including seasonal changes, influence whether the indoor environment is evaluated as comfortable or not. The results suggest...

  18. Cultural influences on children's understanding of the human body and the concept of life.

    Science.gov (United States)

    Panagiotaki, Georgia; Nobes, Gavin

    2014-09-01

    This study aimed to identify the age by which children begin to demonstrate a biological understanding of the human body and the idea that the purpose of body functioning is to maintain life. The study also explored the influence of education, culturally specific experiences and religion on knowledge acquisition in this domain. Children aged between 4 and 7 years from three different cultural backgrounds (White British, British Muslim, and Pakistani Muslim) were interviewed about the human body and its functioning. At least half of the 4- to 5-year-olds in each cultural group, and almost all 6- to 7-year-olds, referred to the maintenance of life when explaining organs' functions and so were classified as 'life theorizers'. Pakistani Muslim children gave fewer biological responses to questions about organs' functions and the purpose of eating and breathing, but referred to life more than their British counterparts. Irrespective of cultural group, older children understood organ location and function better than younger children. These findings support Jaakkola and Slaughter's (2002, Br. J. Dev. Psychol., 20, 325) view that children's understanding of the body as a 'life machine' emerges around the ages of 4-5 years. They also suggest that, despite many similarities in children's ideas cross-culturally, different educational input and culturally specific experiences influence aspects of their biological understanding.

  19. Do robots have goals? How agent cues influence action understanding in non-human primates.

    Science.gov (United States)

    Kupferberg, Aleksandra; Glasauer, Stefan; Burkart, Judith M

    2013-06-01

    The capacity to understand goals and intentions emerges early and universally in humans and is a basic precondition for the interpretation and prediction of others' actions, be it other humans, animals, or even robots. It is unclear, however, how this goal attribution system is acquired, in particular with regard to the role of prior experience with the actor and visual characteristics that are necessary. In four preferential looking time experiments we examined how familiarity, appearance, and movement of different agents influence the capability of marmosets to perceive the behavior of these agents as goal directed. To this end we compared the monkeys' reactions to the same goal-directed actions performed by four different agents: a human actor, a conspecific, a monkey-like small robot, and a black box. The results showed that monkeys attributed goals to the human actor, the conspecific, and the robot, but not the box. Thus, the monkeys extended their capacity for goal attribution not only to familiar agents, but also to agents not previously encountered, provided that they had some conspecific-like features. Our results suggest that in non-human primates, the system for goal attribution does not require previous experience with a specific agent or agent-category, as long as it exhibits certain visual characteristics like face, body or legs. Furthermore, the results suggest that the capacity to attribute goals emerged very early during evolution and, at least in marmoset monkeys, does not necessarily require pre-learned associations in order to fulfill its function when dealing with unfamiliar agents.

  20. Humans (really are animals: Picture-book reading influences five-year-old urban children’s construal of the relation between humans and non-human animals

    Directory of Open Access Journals (Sweden)

    Sandra R Waxman

    2014-03-01

    Full Text Available What is the relation between humans and nonhuman animals? From a biological perspective, we view humans as one species among many, but in the fables and films we create for children, we often offer an anthropocentric perspective, imbuing nonhuman animals with human-like characteristics. What are the consequences of these distinctly different perspectives on children’s reasoning about the natural world? Some have argued that children universally begin with an anthropocentric perspective and that acquiring a biological perspective requires a basic conceptual change (cf. Carey 1985. But recent work reveals that this anthropocentric perspective, evidenced in urban five-year-olds, is not evident in three-year-olds (Herrmann et al. 2010. This indicates that the anthropocentric perspective is not an obligatory first step in children’s reasoning about biological phenomena. In the current paper, we introduced a priming manipulation to assess whether five-year-olds’ reasoning about a novel biological property is influenced by the perspectives they encounter in children’s books. Just before participating in a reasoning task, each child read a book about bears with an experimenter. What varied was whether bears were depicted from an anthropomorphic (Berenstain Bears or biological perspective (Animal Encyclopedia. The priming had a dramatic effect. Children reading the Berenstain Bears showed the standard anthropocentric reasoning pattern, but those reading the Animal Encyclopedia adopted a biological pattern. This offers evidence that urban five-year-olds can adopt either a biological or a human-centered stance, depending upon the context. Thus, children’s books and other media are double-edged swords. Media may (inadvertently support human-centered reasoning in young children, but may also be instrumental in redirecting children’s attention to a biological model.

  1. Assessment of human body influence on exposure measurements of electric field in indoor enclosures.

    Science.gov (United States)

    de Miguel-Bilbao, Silvia; García, Jorge; Ramos, Victoria; Blas, Juan

    2015-02-01

    Personal exposure meters (PEMs) used for measuring exposure to electromagnetic fields (EMF) are typically used in epidemiological studies. As is well known, these measurement devices cause a perturbation of real EMF exposure levels due to the presence of the human body in the immediate proximity. This paper aims to model the alteration caused by the body shadow effect (BSE) in motion conditions and in indoor enclosures at the Wi-Fi frequency of 2.4 GHz. For this purpose, simulation techniques based on ray-tracing have been carried out, and their results have been verified experimentally. A good agreement exists between simulation and experimental results in terms of electric field (E-field) levels, and taking into account the cumulative distribution function (CDF) of the spatial distribution of amplitude. The Kolmogorov-Smirnov (KS) test provides a P-value greater than 0.05, in fact close to 1. It has been found that the influence of the presence of the human body can be characterized as an angle of shadow that depends on the dimensions of the indoor enclosure. The CDFs show that the E-field levels in indoor conditions follow a lognormal distribution in the absence of the human body and under the influence of BSE. In conclusion, the perturbation caused by BSE in PEMs readings cannot be compensated for by correction factors. Although the mean value is well adjusted, BSE causes changes in CDF that would require improvements in measurement protocols and in the design of measuring devices to subsequently avoid systematic errors.

  2. Intrinsic Noise Level of Noise Cross-Correlation Functions and its Implication to Source Population of Ambient noises

    Science.gov (United States)

    Chen, Ying-Nien; Gung, Yuancheng; Chiao, Ling-Yun; Rhie, Junkee

    2017-01-01

    SUMMARYWe present a quantitative procedure to evaluate the intrinsic noise level (INL) of the noise cross-correlation function (NCF). The method is applied to realistic NCFs derived from the continuous data recorded by the seismic arrays in Taiwan and Korea. The obtained temporal evolution of NCF noise level follows fairly the prediction of the theoretical formulation, confirming the feasibility of the method. We then apply the obtained INL to the assessment of data quality and the source characteristics of ambient noise. We show that the INL-based signal-to-noise ratio provides an exact measure for the true noise level within the NCF and better resolving power for the NCF quality, and such measurement can be implemented to any time windows of the NCFs to evaluate the quality of overtones or coda waves. Moreover, since NCF amplitudes are influenced by both the population and excitation strengths of noises, while INL is primarily sensitive to the overall source population, with information from both measurements, we may better constrain the source characteristics of seismic ambient noises.

  3. [Influence of the human blood serum on contractility and beta-adrenoreactyvity of the isolated human myocardium].

    Science.gov (United States)

    Korotaeva, K N; Viaznikov, V A; Tsirkin, V I; Kostiaev, A A

    2011-01-01

    On strips of the isolated myocardium of right hearts auriculum of the 43 patients with ischemic illness of heart and 9 patients with heart diseases of various ethyology at statement venous canule during aorto-coronary shunting, estimated influence of adrenaline (10(-9)-10(-4) g/ml) on amplitude caused by electrostimulus (1H, 5ms, 25-30 V) contractions, and also inotropic and adrenomodulation activity of serum blood (in dilution 1 : 10000, 1: 1000, 1 : 500, 1: 100, 1 : 50, 1: 10 and 1 : 5) nonpregnant women. Direct dependence of amplitude of contraction on size of fraction of of blood emission on Teyholts is revealed. It means, that strips of right auriculum myocardium reflect contractility of a left ventriculum myocardium. Adrenaline in concentration 10(-7)-10(-6) g/ml dependent of dose raised amplitude of the caused contraction not influencing it in concentration of 10(-9) and 10(-8) g/ml (the constant of dissotiation has 2 x 10(-7) g/ml), that as a whole, speaks about decrease in efficiency of activation beta-AP. Blood Serum in dissolutions 1 : 10000-1 : 50 did not influence on amplitude of contraction, and in dissolutions 1 : 10 and 1 : 5 strengthened it, that speaks presence in blood the endogenous activator of myocyte contractility (EAMC). Serum showed beta-adrenomodulation activity that speaks presence in it endogenous sensitizer of beta-adrenoreceptors (ESBAR) and endogenous blocker of beta-adrenoreceptors (EBBAR). In particular, in experiences with adrenaline in subthreshold concentration (10(-8) g/ml) serum showed ESBAR-activity (in dissolutions 1 : 1000, 1 : 500, 1 : 100 and 1 : 50), and in experiences with adrenaline in as much as possible effective concentration (10(-6) g/ml) serum showed ESBAR-activity (in dissolutions 1 : 50 and 1 : 10) and EBBAR-activity (in dissolutions 1:500) Hence, containing in blood serum endogenous modulators of beta-adrenoreactivity - ESBAR and EBBAR can modulate efficiency of beta-adrenoreceptors activation of human

  4. Economic growth and marine biodiversity: influence of human social structure on decline of marine trophic levels.

    Science.gov (United States)

    Clausen, Rebecca; York, Richard

    2008-04-01

    We assessed the effects of economic growth, urbanization, and human population size on marine biodiversity. We used the mean trophic level (MTL) of marine catch as an indicator of marine biodiversity and conducted cross-national time-series analyses (1960-2003) of 102 nations to investigate human social influences on fish catch and trends in MTL. We constructed path models to examine direct and indirect effects relating to marine catch and MTL. Nations' MTLs declined with increased economic growth, increased urbanization, and increased population size, in part because of associated increased catch. These findings contradict the environmental Kuznets curve hypothesis, which claims that economic modernization will reduce human impact on the environment. To make informed decisions on issues of marine resource management, policy makers, nonprofit entities, and professional societies must recognize the need to include social analyses in overall conservation-research strategies. The challenge is to utilize the socioeconomic and ecological research in the service of a comprehensive marine-conservation movement.

  5. Influence of mechanical stimulation on human dermal fibroblasts derived from different body sites.

    Science.gov (United States)

    Kuang, Ruixia; Wang, Zhiguo; Xu, Quanchen; Liu, Su; Zhang, Weidong

    2015-01-01

    Mechanical stimulation is highly associated with pathogenesis of human hypertrophic scar. Although much work has focused on the influence of mechanical stress on fibroblast populations from various tissues and organs in the human body, their effects on cultured dermal fibroblasts by the area of the body have not been as well studied. In this study, cultures of skin fibroblasts from two different body sites were subjected to cyclic mechanical stimulation with a 10% stretching amplitude at a frequency of 0.1 Hz for 24, 36 and 48 hours, respectively, and thereafter harvested for experimental assays. Fibroblasts from scapular upper back skin, subjected to mechanical loads for 36 and 48 hours, respectively, were observed to proliferate at a higher rate and reach confluent more rapidly during in vitro culturing, had higher expression levels of mRNA and protein production of integrin β1, p130Cas and TGF β1 versus those from medial side of upper arm. These data indicate that skin fibroblasts, with regard to originated body sites studied in the experiments, display a diversity of mechanotransduction properties and biochemical reactions in response to applied mechanical stress, which contributes to the increased susceptibility to hypertrophic scars formation at certain areas of human body characterized by higher skin and muscle tension.

  6. Influence of neopterin on generation of reactive species by myeloperoxidase in human neutrophils.

    Science.gov (United States)

    Razumovitch, Julia A; Fuchs, Dietmar; Semenkova, Galina N; Cherenkevich, Sergei N

    2004-04-07

    Increased neopterin concentrations in human serum indicate activation of cell-mediated immune response. Earlier we have shown that neopterin enhanced generation of singlet oxygen, hydroxyl radical and nitric oxide in human peripheral blood neutrophils by NADPH-independent pathways. To further investigate a participation of neopterin in reactive species production by neutrophils, we studied its influence on myeloperoxidase (MPO) activity. MPO was isolated from human peripheral blood neutrophils from healthy donors. Generation of reactive species by MPO/H(2)O(2) in Earl's solution (pH=7.2) at 37 degrees C was investigated by monitoring of chemiluminescence using luminol as light emitter. In the MPO/H(2)O(2) system, neopterin increased singlet oxygen in a concentration-dependent manner, but it decreased formation of other oxidizing species. Comparing several oxygen scavengers, formation of reactive species was totally blocked by sodium azide (NaN(3)), both in the presence and in the absence of neopterin. Superoxide dismutase (SOD) and d-mannitol insignificantly decreased chemiluminescence of this reaction, but diazabicyclo[2.2.2]octane (DABCO) strongly inhibited it. We conclude that the effects of neopterin on neutrophils' MPO are directed to increase singlet oxygen and to decrease other reactive species via inhibition of MPO and/or scavenging of reactive species.

  7. Influence of the mechanical properties of a manipulandum on human operator dynamics. II. Viscosity.

    Science.gov (United States)

    Jones, L A; Hunter, I W

    1993-01-01

    The influence of the viscosity of a manipulandum used by a human operator in a position-control pursuit-tracking task was examined. An active servo-system was used to set the viscosity of a manipulandum (motor) connected to the forearm to one of seven levels ranging in a geometric series from 12 to 800 N.s/m. During each condition the viscosity of the motor was held constant by a computer while subjects tracked, by moving their forearm in the sagittal plane, a visually presented target whose position changed randomly every 1.5 s for 255 s. Nonparametric and parametric impulse response functions were calculated between the input (target) and output (position) in each tracking condition. Nonparametric analyses revealed that subjects became sluggish at higher viscosities (above 200 N.s/m) and took longer to reach the target. A second-order low-pass transfer function was found to provide a very good description of tracking performance at each viscous level. The gain and damping parameter of this transfer function were not affected by the manipulandum's viscosity, whereas both the pure delay and natural frequency of the human operator system decreased systematically with increasing manipulandum viscosity. These findings suggest that over the range of viscosities studied, there is no speed-accuracy trade-off in terms of determining an optimal level of manipulandum viscosity for a human operator, and that a less viscous interface will result in faster performance.

  8. TMS reveals a direct influence of spinal projections from human SMAp on precise force production.

    Science.gov (United States)

    Entakli, Jonathan; Bonnard, Mireille; Chen, Sophie; Berton, Eric; De Graaf, Jozina B

    2014-01-01

    The corticospinal (CS) system plays an important role in fine motor control, especially in precision grip tasks. Although the primary motor cortex (M1) is the main source of the CS projections, other projections have been found, especially from the supplementary motor area proper (SMAp). To study the characteristics of these CS projections from SMAp, we compared muscle responses of an intrinsic hand muscle (FDI) evoked by stimulation of human M1 and SMAp during an isometric static low-force control task. Subjects were instructed to maintain a small cursor on a target force curve by applying a pressure with their right precision grip on a force sensor. Neuronavigated transcranial magnetic stimulation was used to stimulate either left M1 or left SMAp with equal induced electric field values at the defined cortical targets. The results show that the SMAp stimulation evokes reproducible muscle responses with similar latencies and amplitudes as M1 stimulation, and with a clear and significant shorter silent period. These results suggest that (i) CS projections from human SMAp are as rapid and efficient as those from M1, (ii) CS projections from SMAp are directly involved in control of the excitability of spinal motoneurons and (iii) SMAp has a different intracortical inhibitory circuitry. We conclude that human SMAp and M1 both have direct influence on force production during fine manual motor tasks. © 2013 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  9. Analysis of complex patterns of human exposure and immunity to Schistosomiasis mansoni: the influence of age, sex, ethnicity and IgE.

    Directory of Open Access Journals (Sweden)

    Angela Pinot de Moira

    Full Text Available BACKGROUND: Numerous factors may influence Schistosoma infection intensity and prevalence within endemic communities, including exposure-related factors such as local environment and behaviour, and factors relating to susceptibility to infection such as immunology and genetics. While animal studies performed in the laboratory can be tightly controlled, human populations are highly heterogeneous, varying according to demographic characteristics, genetic background and exposure to infection. The heterogeneous nature of human water contact behaviour in particular makes it difficult to distinguish between a lack of cercarial exposure and reduced susceptibility to infection as the cause for low levels of infection in the field. METHODS AND PRINCIPAL FINDINGS: In this study we investigate risk factors for Schistosoma mansoni infection in a rural Ugandan fishing community receiving treatment as part of a multi-disciplinary longitudinal reinfection study. More specifically, we examine the influence that age, sex and ethnic background have on susceptibility to reinfection after anti-helminth drug treatment, but use individual estimates of cercarial exposure and multivariable methods in an attempt to remove noise created by environmental and behavioural heterogeneities. We then investigate whether schistosome-specific IgE immune responses could account for any remaining variations in susceptibility to reinfection. Our findings suggest that observed ethnic- and sex-related variations in S. mansoni reinfection were due to variations in cercarial exposure, as opposed to biological differences in susceptibility to infection. Age-related differences in reinfection were not explained by exposure, however, and appeared linked to the balance of IgE and IgG(4 to the tegumental antigen SmTAL1 (formerly Sm22.6, which itself was significantly related to resistance to reinfection. CONCLUSIONS: This study highlights the benefit of taking a multidisciplinary approach in

  10. Low-noise amplifier

    Directory of Open Access Journals (Sweden)

    V. B. Gulkov

    2012-11-01

    Full Text Available The mixture of signal and noise processing device is considered in this article. It contains two channels: the main channel (MC contains the mixture of signal and noise, and compensation channel (CC that extracts just a noise from the mixture. The feature of the processing circuit is that the mixture samples are formed by short impulses at the moments of passing signal through zero. Further antiphase noise is set in the channels, adder by which the noise is removed from mixture is set on the cannels output. Study of the described device was carried out for simulated AM signal and white Gaussian noise in simulation environment Matlab. The results are shown, that device reduces noise by 16 dB of power.

  11. Formation of the peak amplitude of blood flow oscillations at a frequency of 0.1 Hz in the human cardiovascular system by the noise effect on the heart

    Science.gov (United States)

    Grinevich, Andrey A.; Tankanag, Arina V.; Chemeris, Nikolay K.

    2017-04-01

    In the framework of our previous hypothesis about the participation of structural and hydrodynamic properties of the vascular bed in the formation of the 0.1-Hz component of blood flow oscillations in the human cardiovascular system and on the basis of the reduced hydrodynamic model, the role of additive stochastic perturbations of the operation of the single-chamber pump that simulates the heart was investigated. It was shown that aperiodic noise modulation of the rigidity of the walls of the pump or its valves generates low-frequency oscillations of pressure of arterial vascular bed with the spectral components at a frequency close to 0.1 Hz.

  12. Mathematical modeling of complex noise barriers

    Energy Technology Data Exchange (ETDEWEB)

    Hayek, S.I.

    1982-01-01

    Mathematical modeling of the noise reduction efficiency of highway noise barriers depends on the shape and absorptivity of the barrier, the influence of the impedance of the ground under the receiver, the atmospheric conditions as well as traffic details. The mathematical model for a barrier's noise reduction requires the knowledge of point-to-point acoustic diffraction models. In many instances, the shape of the barrier is simple; such as thin wall (edge), sharp wedge, and cylindrically topped berms. However, new designs of more efficient barriers have been investigated recently.

  13. Noise from wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Fegeant, Olivier [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Building Sciences

    2002-02-01

    A rapid growth of installed wind power capacity is expected in the next few years. However, the siting of wind turbines on a large scale raises concerns about their environmental impact, notably with respect to noise. To this end, variable speed wind turbines offer a promising solution for applications in densely populated areas like the European countries, as this design would enable an efficient utilisation of the masking effect due to ambient noise. In rural and recreational areas where wind turbines are sited, the ambient noise originates from the action of wind on the vegetation and about the listener's ear (pseudo-noise). It shows a wind speed dependence similar to that of the noise from a variable speed wind turbine and can therefore mask the latter for a wide range of conditions. However, a problem inherent to the design of these machines is their proclivity to pure tone generation, because of the enhanced difficulty of avoiding structural resonances in the mechanical parts. Pure tones are deemed highly annoying and are severely regulated by most noise policies. In relation to this problem, the vibration transmission of structure-borne sound to the tower of the turbine is investigated, in particular when the tower is stiffened at its upper end. Furthermore, since noise annoyance due to wind turbine is mostly a masking issue, the wind-related sources of ambient noise are studied and their masking potentials assessed. With this aim, prediction models for wind-induced vegetation noise and pseudo-noise have been developed. Finally, closely related to the effect of masking, is the difficulty, regularly encountered by local authorities and wind farm developers, to measure noise immission from wind turbines. A new measurement technique has thus been developed in the course of this work. Through improving the signal-to-noise ratio between wind turbine noise and ambient noise, the new technique yields more accurate measurement results.

  14. Influence of ganciclovir prophylaxis on citomegalovirus, human herpesvirus 6, and human herpesvirus 7 viremia in renal transplant recipients.

    Science.gov (United States)

    Galarraga, M C; Gomez, E; de Oña, M; Rodriguez, A; Laures, A; Boga, J A; Melon, S

    2005-06-01

    In order to know the influence of ganciclovir (GCV) prophylaxis on cytomegalovirus (CMV) human herpesvirus (HHV)-6 and HHV-7 replication in renal transplant recipients, three groups were studies: 54 patients without GCV; 29, with short-term GCV prophylaxis (less than 30 days); and 51, with long-term GCV prophylaxis (more than 60 days). CMV viremia was more prevalent in the first group (74%, 55%, and 29%, respectively), but CMV replication was also found in 14 patients during therapy, in the other two groups. The antiviral did not affect the prevalence of HHV-6 (67.2%) or HHV-7 (76%), but HHV-6 viremia appeared later (42 +/- 31 vs 21 +/- 25/38 +/- 29 days posttransplant) and was shorter (29 +/- 30 vs 62 +/- 34/41 +/- 33 days) among patients with long-term GCV prophylaxis. On the other hand, CMV viremia was longer when HHV-6 replication was present (40 +/- 25 days vs 18 +/- 16 days). In addition, HHV-7 DNA was detected in all patients with CMV disease.

  15. Ambiguity noise analysis of a SAR system

    Science.gov (United States)

    Tian, Haishan; Chang, Wenge; Li, Xiangyang

    2015-12-01

    The presence of range and azimuth (or Doppler) ambiguities in synthetic aperture radars (SARs) is well known. The ambiguity noise is related to the antenna pattern and the value of pulse repetition frequency (PRF). Because a new frequency modulated continuous wave (FMCW) SAR has the characters of low cost and small size, and the capacity of real-time signal processing, the antenna will likely vibrate or deform due to a lack of the stabilized platform. And the value of PRF cannot be much high because of the high computation burden for the real-time processing. The aim of this study is to access and improve the performance of a new FMCW SAR system based on the ambiguity noise. First, the quantitative analysis of the system's ambiguity noise level is performed; an antenna with low sidelobes is designed. The conclusion is that the range ambiguity noise is small; the azimuth ambiguity noise is somewhat increased, however, it is sufficiently small to have marginal influence on the image quality. Finally, the ambiguity noise level is measured using the imaging data from a Ku-band FMCW SAR. The results of this study show that the measured noise level coincides with the theoretical noise level.

  16. The Role that Natural Environment Plays in Reducing Noise Pollution

    Directory of Open Access Journals (Sweden)

    Nasim Saber Maash

    1999-03-01

    Full Text Available Noise pollution is one of the major problems for the present time and it can affect the life of human being. Noise pollution is excessive, displeasing human, animal or machine-created environmental noise that disrupts the activity or balance of human or animal life. Researchers have mentioned a lot of devastating effects of noise that can disrupt the physical and psychological health of human beings. Noise pollution has also been considered as an important issue which needs to be solved in industrial countries and also as a main factor that is required to be minimized in factory construction and also in producing machinery. In the current article we are aimed at discussing some solutions that natural environment can bring to mankind regarding the reduction of noise pollution.

  17. Influence of wheel polygonal wear on interior noise of high-speed trains%高速列车车轮多边形对车内噪声的影响

    Institute of Scientific and Technical Information of China (English)

    Jie ZHANG; Guang-xu HAN; Xin-biao XIAO; Rui-qian WANG; Yue ZHAO; Xue-song JIN

    2014-01-01

    This work presents a detailed investigation conducted into the relationships between wheel polygonal wear and wheel/rail noise, and the interior noise of high-speed trains through extensive experiments and numerical simulations. The field experiments include roundness measurement and characteristics analysis of the high-speed wheels in service, and analysis on the effect of re-profiling on the interior noise of the high-speed coach. The experimental analysis shows that wheel polygonal wear has a great impact on wheel/rail noise and interior noise. In the numerical simulation, the model of high-speed wheel/rail noise caused by the uneven wheel wear is developed by means of the high-speed wheel-track noise software (HWTNS). The calculation model of the interior noise of a high-speed coach is developed based on the hybrid of the finite element method and the statistic energy analysis (FE-SEA). The numerical simulation analyses the effect of the polygonal wear characteristics, such as roughness level, polygon order (or wavelength), and polygon phase, on wheel/rail noise and interior noise of a high-speed coach. The numerical results show that different polygon order with nearly the same roughness levels can cause different wheel/rail noises and interior noises. The polygon with a higher roughness level can cause a larger wheel/rail noise and a larger interior noise. The combination of different polygon phases can make a different wheel circle diameter difference due to wear, but its effect on the interior noise level is not great. This study can provide a basis for improving the criteria for high-speed wheel re-profiling of China’s high-speed trains.

  18. Caveolin-1 influences human influenza A virus (H1N1 multiplication in cell culture

    Directory of Open Access Journals (Sweden)

    Hemgård Gun-Viol

    2010-05-01

    Full Text Available Abstract Background The threat of recurring influenza pandemics caused by new viral strains and the occurrence of escape mutants necessitate the search for potent therapeutic targets. The dependence of viruses on cellular factors provides a weak-spot in the viral multiplication strategy and a means to interfere with viral multiplication. Results Using a motif-based search strategy for antiviral targets we identified caveolin-1 (Cav-1 as a putative cellular interaction partner of human influenza A viruses, including the pandemic influenza A virus (H1N1 strains of swine origin circulating from spring 2009 on. The influence of Cav-1 on human influenza A/PR/8/34 (H1N1 virus replication was determined in inhibition and competition experiments. RNAi-mediated Cav-1 knock-down as well as transfection of a dominant-negative Cav-1 mutant results in a decrease in virus titre in infected Madin-Darby canine kidney cells (MDCK, a cell line commonly used in basic influenza research as well as in virus vaccine production. To understand the molecular basis of the phenomenon we focussed on the putative caveolin-1 binding domain (CBD located in the lumenal, juxtamembranal portion of the M2 matrix protein which has been identified in the motif-based search. Pull-down assays and co-immunoprecipitation experiments showed that caveolin-1 binds to M2. The data suggest, that Cav-1 modulates influenza virus A replication presumably based on M2/Cav-1 interaction. Conclusion As Cav-1 is involved in the human influenza A virus life cycle, the multifunctional protein and its interaction with M2 protein of human inf