Structural-thermodynamic analysis of the relationship between the half-width and the position of the absorption band maxima in the low-frequency IR spectra of liquid systems

2007 ◽  
Vol 74 (4) ◽  
pp. 230
Author(s):  
V. N. Demidov ◽  
V. G. Puzenko ◽  
A. I. Savinova
Keyword(s):  
Absorption Band ◽  
Ir Spectra ◽  
Thermodynamic Analysis ◽  
Low Frequency ◽  
Half Width ◽  
Liquid Systems ◽  
The Relationship

Representation of stimulus azimuth by low-frequency neurons in inferior colliculus of the cat

1985 ◽  
Vol 53 (1) ◽  
pp. 43-59 ◽  
Author(s):  
L. M. Aitkin ◽  
J. D. Pettigrew ◽  
M. B. Calford ◽  
S. C. Phillips ◽  
L. Z. Wise
Keyword(s):  
Inferior Colliculus ◽  
Sound Source ◽  
Low Frequency ◽  
Stimulus Location ◽  
Small Sample ◽  
Half Width ◽  
Medial Side ◽  
Unit Classes ◽  
Contralateral Ear ◽  
The Relationship

The responses to changes in stimulus azimuth of 204 neurons in the inferior colliculus of the cat with best frequencies of less than 3 kHz were studied. Three main unit classes were identified: omnidirectional units uninfluenced by speaker azimuth (39%); multipeaked units with several azimuthal regions at which peak firing occurred (9%); and azimuth-selective units that showed clear preferences for a discrete range of sound-source azimuths (52%). Alterations in stimulus intensity produced little change in the shapes of profiles relating firing rate to stimulus azimuth (azimuth functions), but the peaks of these functions could shift by up to 20 degrees. Similar observations were made for a small sample of units, each of which was examined with a variety of stimulus frequencies. The pinnae were removed bilaterally in 11 cats, and azimuth functions for 35 units were measured both binaurally and with the ipsilateral or contralateral ear occluded. Evidence was found for facilitative or suppressive interactions, as a function of stimulus azimuth, between monaural inputs. The sharpness of an azimuth function was expressed by the half-width of the function, i.e., the number of degrees of azimuth between the peak of the function and the point at which 50% of maximum firing occurred on the medial side of the peak. When half-widths were plotted as a function of best frequency, it was found that the sharpest azimuth functions occurred for units with best frequencies between 1.1 and 1.5 kHz. Most units in the lowest two octaves (0.1-0.4 kHz) or having best frequencies between 2 and 3 kHz were omnidirectional. The relationship between half-width and the azimuth at which peak firing occurred (best azimuth) revealed that a range of best azimuths between 10 and 40 degrees contralateral contained the sharpest azimuth functions. When best frequency was plotted against best azimuth, it was observed that the majority of units (93%) had best azimuths in the contralateral hemifield. For frequencies between 0.7 and 1.7 kHz, best azimuths occurred relatively evenly between 10 and 60 degrees contralateral. These data suggested that for frequencies between 1.2 and 1.4 kHz, at least, the best azimuths of different units with the same best frequency collectively provide information about stimulus location across much of the contralateral hemifield.(ABSTRACT TRUNCATED AT 400 WORDS)

Practical High Resolution Microscopy

1968 ◽  
Vol 26 ◽  
pp. 302-303
Author(s):  
P. A. Marsh ◽  
T. Mullens ◽  
D. Price
Keyword(s):  
High Resolution ◽  
Magnetic Fields ◽  
Low Frequency ◽  
Resolving Power ◽  
Careful Attention ◽  
Electron Microscopes ◽  
The Relationship ◽  
High Resolution Microscopy ◽  
New Facilities

It is possible to exceed the guaranteed resolution on most electron microscopes by careful attention to microscope parameters essential for high resolution work. While our experience is related to a Philips EM-200, we hope that some of these comments will apply to all electron microscopes.The first considerations are vibration and magnetic fields. These are usually measured at the pre-installation survey and must be within specifications. It has been our experience, however, that these factors can be greatly influenced by the new facilities and therefore must be rechecked after the installation is completed. The relationship between the resolving power of an EM-200 and the maximum tolerable low frequency interference fields in milli-Oerstedt is 10 Å - 1.9, 8 Å - 1.4, 6 Å - 0.8.

scholarly journals Slithering CSF: Cerebrospinal Fluid Dynamics in the Stationary and Moving Viper Boa, Candoia aspera

Biology ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 672
Author(s):  
Bruce A. Young ◽  
Skye Greer ◽  
Michael Cramberg
Keyword(s):  
Cerebrospinal Fluid ◽  
Cardiac Cycle ◽  
Low Frequency ◽  
Mean Amplitude ◽  
The Body ◽  
Body Waves ◽  
Lower Amplitude ◽  
Lateral Undulation ◽  
Recovery From Anesthesia ◽  
The Relationship

In the viper boa (Candoia aspera), the cerebrospinal fluid (CSF) shows two stable overlapping patterns of pulsations: low-frequency (0.08 Hz) pulses with a mean amplitude of 4.1 mmHg that correspond to the ventilatory cycle, and higher-frequency (0.66 Hz) pulses with a mean amplitude of 1.2 mmHg that correspond to the cardiac cycle. Manual oscillations of anesthetized C. aspera induced propagating sinusoidal body waves. These waves resulted in a different pattern of CSF pulsations with frequencies corresponding to the displacement frequency of the body and with amplitudes greater than those of the cardiac or ventilatory cycles. After recovery from anesthesia, the snakes moved independently using lateral undulation and concertina locomotion. The episodes of lateral undulation produced similar influences on the CSF pressure as were observed during the manual oscillations, though the induced CSF pulsations were of lower amplitude during lateral undulation. No impact on the CSF was found while C. aspera was performing concertina locomotion. The relationship between the propagation of the body and the CSF pulsations suggests that the body movements produce an impulse on the spinal CSF.

scholarly journals On the Relationship between Regional Ocean Heat Content and Sea Surface Height

2017 ◽  
Vol 30 (22) ◽  
pp. 9195-9211 ◽  
Author(s):  
John T. Fasullo ◽  
Peter R. Gent
Keyword(s):  
Time Scales ◽  
Low Frequency ◽  
Heat Content ◽  
Sea Surface Height ◽  
Ocean Heat Content ◽  
Ocean Dynamics ◽  
Sea Surface ◽  
Altimeter Data ◽  
Model Control ◽  
The Relationship

Abstract An accurate diagnosis of ocean heat content (OHC) is essential for interpreting climate variability and change, as evidenced for example by the broad range of hypotheses that exists for explaining the recent hiatus in global mean surface warming. Potential insights are explored here by examining relationships between OHC and sea surface height (SSH) in observations and two recently available large ensembles of climate model simulations from the mid-twentieth century to 2100. It is found that in decadal-length observations and a model control simulation with constant forcing, strong ties between OHC and SSH exist, with little temporal or spatial complexity. Agreement is particularly strong on monthly to interannual time scales. In contrast, in forced transient warming simulations, important dependencies in the relationship exist as a function of region and time scale. Near Antarctica, low-frequency SSH variability is driven mainly by changes in the circumpolar current associated with intensified surface winds, leading to correlations between OHC and SSH that are weak and sometimes negative. In subtropical regions, and near other coastal boundaries, negative correlations are also evident on long time scales and are associated with the accumulated effects of changes in the water cycle and ocean dynamics that underlie complexity in the OHC relationship to SSH. Low-frequency variability in observations is found to exhibit similar negative correlations. Combined with altimeter data, these results provide evidence that SSH increases in the Indian and western Pacific Oceans during the hiatus are suggestive of substantial OHC increases. Methods for developing the applicability of altimetry as a constraint on OHC more generally are also discussed.

NEW ETIOLOGICAL FACTORS OF OCCUPATIONAL HEARING LOSS

2021 ◽  
Author(s):  
V.B. Pankova ◽  
◽  
М.F. Vilk ◽  
◽  
◽  
...  
Keyword(s):  
Hearing Loss ◽  
Low Frequency ◽  
Evidence Base ◽  
Frequency Noise ◽  
Labor Intensity ◽  
Etiological Factors ◽  
Hearing Organ ◽  
The Relationship ◽  
Vascular Stria ◽  
Occupational Hearing Loss

Annotation. On the example of railway and air transport, a number of new issues of occupational hearing loss are shown, requiring study and subsequent implementation in practical health care, as new etiological factors in the development of hearing loss. This concerns the factor of labor intensity, which has a potentiating, pathogenetic significance, along with noise, in the development of hearing loss due to the formation of chronic stress, leading to additional ischemia of the vascular stria and damage to the neuroepithelium of the inner ear. There is a need, along with the development of a methodology for assessing the factor of labor intensity for SOUT of workplaces, to determine the criteria for its negative action when used for the examination of the connection between the disease of the organ of hearing and the profession. In the «List of occupational diseases» in clause 2.4.2. indicated diseases associated with exposure to infrasound (IZ), among the manifestations of which, called sensorineural hearing loss bilateral. However, IZ, as well as low-frequency noise (LFN), were not previously considered as significant adverse factors in relation to the hearing organ in mass clinical trials, therefore, there are no expert criteria for the relationship between hearing loss and their impact, which could be applied in practice, which requires accumulation of evidence base for the subsequent substantiation of an independent nosological form of a disease of the organ of hearing, associated with mechanoacoustic exposure.

scholarly journals The Relationship between Vibratory Sensation and Body Surface Vibration Induced by Low-Frequency Noise

2002 ◽  
Vol 21 (2) ◽  
pp. 87-100 ◽  
Author(s):  
Yukio Takahashi ◽  
Kazuo Kanada ◽  
Yoshiharu Yonekawa
Keyword(s):  
Body Surface ◽  
Mechanical Vibration ◽  
Low Frequency ◽  
The Body ◽  
Frequency Noise ◽  
Low Frequency Noise ◽  
Vibration Acceleration ◽  
Surface Vibration ◽  
Human Body Surface ◽  
The Relationship

Human body surface vibration induced by low-frequency noise was measured at the forehead, the chest and the abdomen. At the same time, subjects rated their vibratory sensation at each of these locations. The relationship between the measured vibration on the body surface and the rated vibratory sensation was examined, revealing that the vibratory sensations perceived in the chest and abdomen correlated closely with the vibration acceleration levels of the body surface vibration. This suggested that a person exposed to low-frequency noise perceives vibration at the chest or abdomen by sensing the mechanical vibration that the noise induces in the body. At the head, on the other hand, it was found that the vibratory sensation correlated comparably with the vibration acceleration level of the body surface vibration and the sound pressure level of the noise stimulus. This finding suggested that the mechanism of perception of vibration in the head is different from that of the perception of vibratory sensation in the chest and the abdomen.

scholarly journals The relationship between S-wave reflectors and deep low-frequency earthquakes in the northern Kinki district, southwestern Japan

2018 ◽  
Vol 70 (1) ◽  
Author(s):  
Shinya Katoh ◽  
Yoshihisa Iio ◽  
Hiroshi Katao ◽  
Masayo Sawada ◽  
Kazuhide Tomisaka ◽  
...  
Keyword(s):  
Low Frequency ◽  
S Wave ◽  
The Relationship

Trans*formative Thinking Through Sound: Artistic Research in Gender and Sound Beyond the Human

2021 ◽  
Vol 4 (1) ◽  
pp. 335-346
Author(s):  
Luca Soudant
Keyword(s):  
Queer Theory ◽  
Low Frequency ◽  
Sound Studies ◽  
Sound Design ◽  
Research Practice ◽  
Sound Waves ◽  
Frequency Sound ◽  
Gender Power ◽  
The Relationship ◽  
Artistic Research

Abstract This article reflects on an ongoing artistic research practice that deals with sound, gender, power, spatiality, and human–nonhuman entanglement. Sparked by a sound design for a less crunchy “lady-friendly” crisp, the research inquires the relationship between gender and sound at human–nonhuman encounter through making and thinking. Drawing on queer theory, sound studies, and posthumanism, it aims to transcend essentialist, vision-focused, and anthropocentric conceptualisations of gender and, as an insight gained from working with low-frequency sound waves, it reflects on sound as material-philosophically demonstrating human–nonhuman interconnectedness. The latter, as this article proposes, may encourage us to horizontalise hierarchies between the human and nonhuman. Finally, this text situates sonic thinking as a mode of trans*formative thinking: a process-oriented philosophy that aims to embrace the messy, queer ways of human–nonhuman relationality, which characterises a vibrant space from which this artistic research will further develop.

Synchronous and baroceptor-sensitive oscillations in skin microcirculation: evidence for central autonomic control

1997 ◽  
Vol 273 (4) ◽  
pp. H1867-H1878 ◽  
Author(s):  
Luciano Bernardi ◽  
Daniel Hayoz ◽  
René Wenzel ◽  
Claudio Passino ◽  
Alessandro Calciati ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Skin Blood Flow ◽  
Muscle Sympathetic Nerve Activity ◽  
Low Frequency ◽  
Doppler Flowmetry ◽  
Sympathetic Modulation ◽  
Baroreflex Stimulation ◽  
The Relationship ◽  
Spontaneous Fluctuations

To determine whether skin blood flow is local or takes part in general regulatory mechanisms, we recorded laser-Doppler flowmetry (LDF; left and right index fingers), blood pressure, muscle sympathetic nerve activity (MSNA), R-R interval, and respiration in 10 healthy volunteers and 3 subjects after sympathectomy. We evaluated 1) the synchronism of LDF fluctuations in two index fingers, 2) the relationship with autonomically mediated fluctuations in other signals, and 3) the LDF ability to respond to arterial baroreflex stimulation (by neck suction at frequencies from 0.02 to 0.20 Hz), using spectral analysis (autoregressive uni- and bivariate, time-variant algorithms). Synchronous LDF fluctuations were observed in the index fingers of healthy subjects but not in sympathectomized patients. LDF fluctuations were coherent with those obtained for blood pressure, MSNA, and R-R interval. LDF fluctuations were leading blood pressure in the low-frequency (LF; 0.1 Hz) band and lagging in the respiratory, high-frequency (HF; ∼0.25 Hz) band, suggesting passive “downstream” transmission only for HF and “upstream” transmission for LF from the microvessels. LDF fluctuations were responsive to sinusoidal neck suction up to 0.1 Hz, indicating response to sympathetic modulation. Skin blood flow thus reflects modifications determined by autonomic activity, detectable by frequency analysis of spontaneous fluctuations.

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