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124 records – page 1 of 13.

The 24-hour pulse wave velocity, aortic augmentation index, and central blood pressure in normotensive volunteers.

https://arctichealth.org/en/permalink/ahliterature104335
Source
Vasc Health Risk Manag. 2014;10:247-51
Publication Type
Article
Date
2014
Author
Tatyana Y Kuznetsova
Viktoria A Korneva
Evgeniya N Bryantseva
Vitaliy S Barkan
Artemy V Orlov
Igor N Posokhov
Anatoly N Rogoza
Author Affiliation
Faculty of Medicine, Petrozavodsk State University, Petrozavodsk, Russia.
Source
Vasc Health Risk Manag. 2014;10:247-51
Date
2014
Language
English
Publication Type
Article
Keywords
Adult
Aged
Algorithms
Blood pressure
Blood Pressure Monitoring, Ambulatory - standards
Circadian Rhythm
Diastole
Female
Healthy Volunteers
Heart rate
Humans
Male
Middle Aged
Predictive value of tests
Pulse Wave Analysis - standards
Reference Values
Russia
Signal Processing, Computer-Assisted
Systole
Time Factors
Vascular Stiffness
Abstract
The purpose of this study was to examine the pulse wave velocity, aortic augmentation index corrected for heart rate 75 (AIx@75), and central systolic and diastolic blood pressure during 24-hour monitoring in normotensive volunteers. Overall, 467 subjects (206 men and 261 women) were recruited in this study. Participants were excluded from the study if they were less than 19 years of age, had blood test abnormalities, had a body mass index greater than 2 7.5 kg/m(2), had impaired glucose tolerance, or had hypotension or hypertension. Ambulatory blood pressure monitoring (ABPM) with the BPLab(®) device was performed in each subject. ABPM waveforms were analyzed using the special automatic Vasotens(®) algorithm, which allows the calculation of pulse wave velocity, AIx@75, central systolic and diastolic blood pressure for "24-hour", "awake", and "asleep" periods. Circadian rhythms and sex differences in these indexes were identified. Pending further validation in prospective outcome-based studies, our data may be used as preliminary diagnostic values for the BPLab ABPM additional index in adult subjects.
Notes
Cites: J Invasive Cardiol. 2009 Jun;21(6):270-719494403
Cites: Hypertens Res. 2012 Oct;35(10):980-722622282
Cites: Am J Hypertens. 2010 Feb;23(2):180-519959999
Cites: J Hypertens. 2013 Jul;31(7):1281-35723817082
Cites: Vasc Health Risk Manag. 2011;7:649-5622140314
Cites: Age (Dordr). 2013 Dec;35(6):2345-5523319362
Cites: Hypertension. 2013 Jun;61(6):1148-923630945
Cites: Hypertension. 2013 Jun;61(6):1168-7623630950
Cites: J Hypertens. 2013 Sep;31(9):1731-6824029863
Cites: Eur Heart J. 2010 Oct;31(19):2338-5020530030
PubMed ID
24812515 View in PubMed
Less detail

Abnormalities in beat to beat complexity of heart rate dynamics in patients with a previous myocardial infarction.

https://arctichealth.org/en/permalink/ahliterature54616
Source
J Am Coll Cardiol. 1996 Oct;28(4):1005-11
Publication Type
Article
Date
Oct-1996
Author
T H Mäkikallio
T. Seppänen
M. Niemelä
K E Airaksinen
M. Tulppo
H V Huikuri
Author Affiliation
Department of Medicine, Oulu University, Finland.
Source
J Am Coll Cardiol. 1996 Oct;28(4):1005-11
Date
Oct-1996
Language
English
Publication Type
Article
Keywords
Adult
Electrocardiography, Ambulatory
Entropy
Female
Heart Rate - physiology
Humans
Male
Models, Statistical
Myocardial Infarction - physiopathology
Research Support, Non-U.S. Gov't
Signal Processing, Computer-Assisted
Abstract
OBJECTIVES: The purpose of this research was to study possible abnormalities in the beat to beat complexity of heart rate dynamics in patients with a previous myocardial infarction. BACKGROUND: Analysis of approximate entropy of time series data provides information on the complexity of both deterministic and random processes. It has been proposed that regularity or loss of complexity of RR interval dynamics may be related to pathologic states, but this hypothesis has not been well tested in cardiovascular disorders. METHODS: Approximate entropy and conventional time and frequency domain measures of RR interval variability were compared between 40 healthy subjects with no evidence of heart disease and 40 patients with coronary artery disease and a previous Q wave myocardial infarction. The groups were matched with respect to age, and cardiac medication was discontinued in the patients with coronary artery disease before the 24-h electrocardiographic recordings. RESULTS: Approximate entropy was significantly higher in the postinfarction patients (1.21 +/- 0.18 [mean +/- SD]) than in the healthy subjects (1.05 +/- 0.11, p
PubMed ID
8837582 View in PubMed
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Acoustically invisible feeding blue whales in Northern Icelandic waters.

https://arctichealth.org/en/permalink/ahliterature267088
Source
J Acoust Soc Am. 2014 Aug;136(2):939-44
Publication Type
Article
Date
Aug-2014
Author
Tomonari Akamatsu
Marianne Helene Rasmussen
Maria Iversen
Source
J Acoust Soc Am. 2014 Aug;136(2):939-44
Date
Aug-2014
Language
English
Publication Type
Article
Keywords
Acoustics - instrumentation
Animals
Balaenoptera - physiology - psychology
Equipment Design
Feeding Behavior
Iceland
Oceans and Seas
Signal Processing, Computer-Assisted
Sound Spectrography
Time Factors
Transducers, Pressure
Vocalization, Animal
Abstract
Fixed passive acoustic monitoring can be used for long-term recording of vocalizing cetaceans. Both presence monitoring and animal density estimation requires the call rates and sound source levels of vocalizations produced by single animals. In this study, blue whale calls were recorded using acoustic bio-logging systems in Skjálfandi Bay off Húsavík, Northeast Iceland, in June 2012. An accelerometer was attached to individual whales to monitor diving behavior. During 21?h recording two individuals, 8?h 45?min and 13?h 2?min, respectively, 105 and 104 lunge feeding events and four calls were recorded. All recorded calls were down-sweep calls ranging from 105 to 48?Hz. The sound duration was 1-2?s. The source level was estimated to be between 158 and 169?dB re 1µPa rms, assuming spherical sound propagation from the possible sound source location to the tag. The observed sound production rates and source levels of individual blue whales during feeding were extremely small compared with those observed previously in breeding grounds. The feeding whales were nearly acoustically invisible. The function of calls during feeding remains unknown.
PubMed ID
25096128 View in PubMed
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Acoustic vector sensor beamforming reduces masking from underwater industrial noise during passive monitoring.

https://arctichealth.org/en/permalink/ahliterature289559
Source
J Acoust Soc Am. 2016 04; 139(4):EL105
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Date
04-2016
Author
Aaron M Thode
Katherine H Kim
Robert G Norman
Susanna B Blackwell
Charles R Greene
Author Affiliation
Marine Physical Laboratory, Scripps Institution of Oceanography, San Diego, California 92093-0205, USA athode@ucsd.edu.
Source
J Acoust Soc Am. 2016 04; 139(4):EL105
Date
04-2016
Language
English
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Keywords
Acoustics - instrumentation
Animals
Environmental Monitoring - instrumentation - methods
Equipment Design
Models, Theoretical
Motion
Noise - adverse effects
Oceans and Seas
Oil and Gas Industry
Pressure
Signal Processing, Computer-Assisted
Signal-To-Noise Ratio
Sound Spectrography
Time Factors
Transducers, Pressure
Vocalization, Animal
Water
Abstract
Masking from industrial noise can hamper the ability to detect marine mammal sounds near industrial operations, whenever conventional (pressure sensor) hydrophones are used for passive acoustic monitoring. Using data collected from an autonomous recorder with directional capabilities (Directional Autonomous Seafloor Acoustic Recorder), deployed 4.1?km from an arctic drilling site in 2012, the authors demonstrate how conventional beamforming on an acoustic vector sensor can be used to suppress noise arriving from a narrow sector of geographic azimuths. Improvements in signal-to-noise ratio of up to 15?dB are demonstrated on bowhead whale calls, which were otherwise undetectable using conventional hydrophones.
PubMed ID
27106345 View in PubMed
Less detail

Acoustic vector sensor beamforming reduces masking from underwater industrial noise during passive monitoring.

https://arctichealth.org/en/permalink/ahliterature289717
Source
J Acoust Soc Am. 2016 04; 139(4):EL105
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Date
04-2016
Author
Aaron M Thode
Katherine H Kim
Robert G Norman
Susanna B Blackwell
Charles R Greene
Author Affiliation
Marine Physical Laboratory, Scripps Institution of Oceanography, San Diego, California 92093-0205, USA athode@ucsd.edu.
Source
J Acoust Soc Am. 2016 04; 139(4):EL105
Date
04-2016
Language
English
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Keywords
Acoustics - instrumentation
Animals
Environmental Monitoring - instrumentation - methods
Equipment Design
Models, Theoretical
Motion
Noise - adverse effects
Oceans and Seas
Oil and Gas Industry
Pressure
Signal Processing, Computer-Assisted
Signal-To-Noise Ratio
Sound Spectrography
Time Factors
Transducers, Pressure
Vocalization, Animal
Water
Abstract
Masking from industrial noise can hamper the ability to detect marine mammal sounds near industrial operations, whenever conventional (pressure sensor) hydrophones are used for passive acoustic monitoring. Using data collected from an autonomous recorder with directional capabilities (Directional Autonomous Seafloor Acoustic Recorder), deployed 4.1?km from an arctic drilling site in 2012, the authors demonstrate how conventional beamforming on an acoustic vector sensor can be used to suppress noise arriving from a narrow sector of geographic azimuths. Improvements in signal-to-noise ratio of up to 15?dB are demonstrated on bowhead whale calls, which were otherwise undetectable using conventional hydrophones.
PubMed ID
27106345 View in PubMed
Less detail

[Age-Related Features of EEG Coherence in Children and Adolescents Living in the European North of Russia].

https://arctichealth.org/en/permalink/ahliterature268694
Source
Fiziol Cheloveka. 2015 Sep-Oct;41(5):74-89
Publication Type
Article
Author
S I Soroko
Zh V Nagornova
V P Rozhkov
N V Shemyakina
Source
Fiziol Cheloveka. 2015 Sep-Oct;41(5):74-89
Language
Russian
Publication Type
Article
Keywords
Adolescent
Adolescent Development - physiology
Aging - physiology
Cerebral Cortex - physiology
Child
Child Development - physiology
Electroencephalography
Female
Humans
Male
Russia
Signal Processing, Computer-Assisted
Abstract
The paper presents data on the formation of spatial synchronization of brain potentials in 91 children aged 7-18 years living in European North of Russia. We estimated coherence values for 19 derivations (pair 171) in five EEG frequency bands (delta, theta, alpha-1, alpha-2 and beta). We described age-related changes, gender differences and topical specific features of the formation of coherence in the left and right hemispheres, and in inter- and intrahemispheric synchronization. We carried out computer assessment of the differences in EEG coherence between three age groups of children in order to determine criteria for identification of children with retarded formation of spatial organization of local EEG processes. Age-related changes in the structure of EEG patterns observed in the study reflect the processes of morphofunctional brain development in children and adolescents at different stages of postnatal ontogenesis under severe conditions of northern climate.
PubMed ID
26601411 View in PubMed
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Altered frequency distribution in the electroencephalogram is correlated to the analgesic effect of remifentanil.

https://arctichealth.org/en/permalink/ahliterature269341
Source
Basic Clin Pharmacol Toxicol. 2015 May;116(5):414-22
Publication Type
Article
Date
May-2015
Author
Carina Graversen
Lasse P Malver
Geana P Kurita
Camilla Staahl
Lona L Christrup
Per Sjøgren
Asbjørn M Drewes
Source
Basic Clin Pharmacol Toxicol. 2015 May;116(5):414-22
Date
May-2015
Language
English
Publication Type
Article
Keywords
Adult
Analgesics, Opioid - administration & dosage
Brain - drug effects - physiopathology
Brain Waves - drug effects
Cross-Over Studies
Denmark
Double-Blind Method
Electroencephalography
Healthy Volunteers
Hot Temperature - adverse effects
Humans
Infusions, Parenteral
Male
Multivariate Analysis
Pain - etiology - physiopathology - prevention & control
Pain Measurement
Pain Perception - drug effects
Pain Threshold - drug effects
Piperidines - administration & dosage
Predictive value of tests
Pressure - adverse effects
Signal Processing, Computer-Assisted
Time Factors
Young Adult
Abstract
Opioids alter resting state brain oscillations by multiple and complex factors, which are still to be elucidated. To increase our knowledge, multi-channel electroencephalography (EEG) was subjected to multivariate pattern analysis (MVPA), to identify the most descriptive frequency bands and scalp locations altered by remifentanil in healthy volunteers. Sixty-two channels of resting EEG followed by independent measures of pain scores to heat and bone pain were recorded in 21 healthy males before and during remifentanil infusion in a placebo-controlled, double-blind crossover study. EEG frequency distributions were extracted by a continuous wavelet transform and normalized into delta, theta, alpha, beta and gamma bands. Alterations relative to pre-treatment responses were calculated for all channels and used as input to the MVPA. Compared to placebo, remifentanil increased the delta band and decreased the theta and alpha band oscillations as a mean over all channels (all p = 0.007). The most discriminative channels in these frequency bands were F1 in delta (83.33%, p = 0.0023) and theta bands (95.24%, p
PubMed ID
25250670 View in PubMed
Less detail

Ambient noise measurements from 100 Hz to 80 kHz in an Alaskan fjord.

https://arctichealth.org/en/permalink/ahliterature224012
Source
J Acoust Soc Am. 1992 Apr;91(4 Pt 1):1990-2003
Publication Type
Article
Date
Apr-1992
Author
S O McConnell
M P Schilt
J G Dworski
Author Affiliation
Areté Associates, La Jolla, California 92038.
Source
J Acoust Soc Am. 1992 Apr;91(4 Pt 1):1990-2003
Date
Apr-1992
Language
English
Publication Type
Article
Keywords
Acoustics
Alaska
Humans
Noise
Oceans and Seas
Seasons
Signal Processing, Computer-Assisted - instrumentation
Sound Spectrography - instrumentation
Water
Weather
Wind
Abstract
Measurements covering a broad frequency range from 100 Hz to 80 kHz have been made in Behm Canal, Alaska. This site represents a fairly deep embayment (400 m) with a soft bottom (porosity of about 0.8) and, hence, the noise detected at the hydrophones is affected negligibly by multipath contributions except possibly at the lowest frequencies. Data were gathered over a wide range of wind speeds (0 to 15 m/s) and during periods of rain and snow. Several unique and noteworthy results were obtained. Foremost was the observation that the wind-generated noise level measured during the winter was approximately 5 dB lower than during the summer for the same wind speeds and air-sea temperature differences (air temperature about the same as or colder than the sea surface). The summer data agree well with the most recent published measurements and are approximately 2 dB higher than the standard Knudsen/Wenz reference spectra. It appeared that below-freezing air temperatures and snow were responsible for the 5 dB offset between the summer and winter data. Most reported wind noise measurements are restricted to frequencies less than 20 kHz. Those that go beyond this frequency display a noticeable hump above the usual--17 dB/decade power-law slope, and the Behm Canal measurements show that this hump continues to 80 kHz where the spectrum rejoins the extension of the canonical power-law slope.
PubMed ID
1597595 View in PubMed
Less detail

Analysis of measurements from the first Swedish universal neonatal hearing screening program.

https://arctichealth.org/en/permalink/ahliterature93945
Source
Int J Audiol. 2007 Nov;46(11):680-5
Publication Type
Article
Date
Nov-2007
Author
Hergils Leif
Author Affiliation
Center for Medical Technology Assessment, Linköping University, Linköping, Sweden. leihe@inr.liu.se
Source
Int J Audiol. 2007 Nov;46(11):680-5
Date
Nov-2007
Language
English
Publication Type
Article
Keywords
Brain Stem - physiology
Cross-Cultural Comparison
Databases as Topic
Evoked Potentials, Auditory, Brain Stem - physiology
Female
Humans
Infant, Newborn
Male
Neonatal Screening - organization & administration
Otoacoustic Emissions, Spontaneous - physiology
Reference Values
Signal Processing, Computer-Assisted
Software
Sweden
United States
Abstract
This study analyses results from the first Swedish UNHS program. It includes over 33 000 measurement files from 14 287 children at two maternity wards. The screening program uses a two-stage TEOAE test procedure. A database was created in MedLog after data transformation in Word and Excel. The coverage rate was 99.1%. Bilateral pass rate after retesting was 97.0%. A unilateral pass criterion would have resulted in 1268 fewer children (9.0% of target group) for retesting and 231 fewer children (1.6% of target group) for diagnostic evaluation. When the first test was performed on the day the child was born, the pass rate was 64.8%; the pass rate increased to 89.2% when testing> or =3 days after birth. High coverage rates and pass rates were found to be possible, independent of the number of children born at the maternity ward. Learning curves were observed in the program with improvements distributed over time. Test performance was clearly better when the children were tested day two after birth or later.
PubMed ID
17978950 View in PubMed
Less detail

Analysis of sway in Parkinson's disease using a new inclinometry-based method.

https://arctichealth.org/en/permalink/ahliterature50748
Source
Mov Disord. 2002 Jul;17(4):663-9
Publication Type
Article
Date
Jul-2002
Author
Maria K Viitasalo
Ville Kampman
Kyösti A Sotaniemi
Seppo Leppävuori
Vilho V Myllylä
Juha T Korpelainen
Author Affiliation
Department of Neurology, University of Oulu, Oulu, Finland.
Source
Mov Disord. 2002 Jul;17(4):663-9
Date
Jul-2002
Language
English
Publication Type
Article
Keywords
Aged
Aged, 80 and over
Equipment Design
Female
Humans
Kinesthesis - physiology
Male
Microcomputers
Middle Aged
Musculoskeletal Equilibrium - physiology
Neurologic Examination - instrumentation
Orientation - physiology
Parkinson Disease - diagnosis - physiopathology
Posture - physiology
Reference Values
Signal Processing, Computer-Assisted - instrumentation
Abstract
In order to analyze balance control, we developed a new inclinometry-based method to provide direct information about body sway in the side-to-side and forward-backward directions. We tested the clinical utility of this method for analyzing balance in Parkinson's disease (PD), and studied the clinical correlates of the balance measures in PD. Postural sway was measured during quiet stance with eyes open and eyes closed in 28 PD patients and in 32 age- and sex-matched control subjects. Postural sway was modeled using side-to-side and forward-backward directional sway movements, sway velocity, and sway area. The amount of postural sway in the PD patients was greater than in the control subjects, the higher level being most marked in patients with severe or long-duration PD. All the side-to-side directional sway parameters were abnormal in the PD patients compared with the control subjects (P
PubMed ID
12210854 View in PubMed
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124 records – page 1 of 13.