scholarly journals Beeinflusst das Tragen einer Gangjustierhilfe in Sicherheitsschuhen die allgemeine Beanspruchung bei Produktionsarbeitern in der Spätschicht?

2021 ◽  
Author(s):  
Isabelle Dürrschnabel ◽  
Lutz Dürrschnabel ◽  
Irina Böckelmann
Keyword(s):  
Frequency Band ◽  
High Frequency ◽  
Total Power ◽  
Sich Eine ◽  
Körperliche Leistungsfähigkeit ◽  
High Frequency Band ◽  
Band Power

Zusammenfassung Hintergrund Sicherheitsschuhe sind Teil einer persönlichen Schutzausrüstung zur Minderung des Unfallrisikos am Arbeitsplatz und bei vielen Tätigkeiten in verschiedenen Berufsgruppen vorgeschrieben. Das Tragen von normierten Arbeitsschuhen kann aufgrund der besonderen Eigenschaften (Passform und Gewicht) zu einer erhöhten Beanspruchung des Arbeiters führen. Eine zusätzliche Optimierung von Arbeitsschuhen, mit dem Ziel der Symmetrisierung des Ganges und der damit einhergehenden Verminderung der Beanspruchung, unter den besonderen Bedingungen des Arbeitsschutzes ist daher anzustreben. In dieser Studie soll überprüft werden, ob das Anbringen einer Gangjustierhilfe mit dem Ziel der Symmetrisierung des Ganges einen Einfluss auf die allgemeine Beanspruchung von Schichtarbeitern hat. Methodik Dafür wurde bei 29 männlichen Probanden (Interventionsgruppe: n = 15, Kontrollgruppe: n = 14) zu 2 Messzeitpunkten während der Spätschicht die Herzfrequenzvariabilität (HRV) kontinuierlich erfasst. Ergebnisse Nach 2‑wöchigem Tragen der Gangjustierhilfe zeigt sich eine signifikante Erhöhung der zeitbezogenen HRV-Parameter bei der Interventionsgruppe. Die frequenzbezogenen Parameter Gesamtleistung (Total Power) und Leistung im High Frequency Band (Power HF Band) zeigen bei der Kontrollgruppe eine Verringerung vom 1. zum 2. Messzeitpunkt. Die Ergebnisse sprechen dafür, dass die Gangjustierhilfe durchaus positive Effekte auf die HRV hat und damit die allgemeine Beanspruchungslage am Arbeitsplatz bei dieser Stichprobe positiv beeinflussen kann. Diskussion Weitere Studien zum Überprüfen eines Effektes mit größeren Fallzahlen und unter Berücksichtigung weitere Gruppierungsmöglichkeiten (bspw. Parameter der Ganganalyse, körperliche Leistungsfähigkeit und Vorerkrankungen) sind jedoch erforderlich.

Cardiovascular control and plasma catecholamines during rest and mental stress: effects of posture

1999 ◽  
Vol 96 (6) ◽  
pp. 567-576 ◽  
Author(s):  
J. H. M. TULEN ◽  
F. BOOMSMA ◽  
A. J. MAN IN ′TVELD
Keyword(s):  
Frequency Band ◽  
High Frequency ◽  
Daily Life ◽  
Plasma Catecholamines ◽  
High Frequency Band ◽  
Standing Posture ◽  
Plasma Adrenaline ◽  
Band Power ◽  
Parasympathetic Regulation ◽  
Sympathetic And Parasympathetic Regulation

In order to understand the complex autonomic adjustments that occur during the psychological challenges of normal daily life, autonomic responses to psychological stress were studied by evaluating the effects of body posture on various indices of sympathetic and parasympathetic regulation during performance of a psychological task. Twelve male subjects were studied in various postures (supine, sitting and standing), and during performance of the Colour Word Test (CWT) when sitting and then when standing. This procedure was subsequently repeated in reverse order (first standing and then sitting) after 15 min of supine rest. Blood samples for assay of plasma catecholamines were obtained before and during each CWT. Spectral analysis of beat-to-beat variations of heart rate (HR) and blood pressure (BP) was applied in order to obtain non-invasive indices of sympathetic and parasympathetic regulation. HR, diastolic BP, mid-frequency band power (0.07-0.14 Hz) of HR and systolic BP, and plasma adrenaline and noradrenaline concentrations showed significant increases when changing from supine to sitting to standing posture, whereas high-frequency band power (0.15-0.50 Hz) of HR decreased in a posture-dependent fashion. In the sitting position, the CWT caused significant increases in HR, BP and plasma adrenaline levels, and decreased HR and BP variability indices. In the standing posture, the CWT responses differed significantly from those during sitting for HR (a mild decrease during standing), high-frequency band power of HR (decreased more while sitting), high-frequency band power of BP (decreased more while standing), and plasma adrenaline responses (larger during sitting). Posture-related differential effects were observed on indices of sympatho-adrenomedullary activation during performance of a psychological challenge, whereas indices of parasympathetic activity indicated primarily less vagolytic effects when the task was performed in the standing posture. Our findings therefore underline the complexity of the adjustments that occur in neurohumoral and haemodynamic parameters during the psychological challenges of daily life.

The SIRIO satellite, 1968––1977: Between scientific engagement and managerial inexperience

2004 ◽  
Vol 34 (2) ◽  
pp. 371-398
Author(s):  
LUCIA ORLANDO
Keyword(s):  
International Economic ◽  
Organizational Structure ◽  
Frequency Band ◽  
High Frequency ◽  
Aerospace Industry ◽  
Space Research ◽  
High Frequency Band ◽  
Political Uncertainty ◽  
The 1960S ◽  
Super High Frequency

ABSTRACT: The story of the first Italian communications satellite, SIRIO, started in 1968, after the failure of the European project for the vector ELDO-PAS. The story up to the launch in 1977 involved the encumbering legacy of the San Marco satellite's success in the 1960s, political uncertainty in Italy, international economic crises of the 1970s, an overtly complex management system, and an inexperienced aerospace industry. Despite these handicaps, SIRIO won the race with its nearest competitor, the European satellite OTS, which had a similar research aim in the super high frequency band. In addition to collecting a large amount of useful data, SIRIO catalyzed the process for developing an improved organizational structure for Italian space research.

Nanoelectromagnetic of the N-doped single wall carbon nanotube in the extremely high frequency band

Nanoscale ◽  
2017 ◽  
Vol 9 (37) ◽  
pp. 14192-14200 ◽  
Author(s):  
B. Aïssa ◽  
M. Nedil ◽  
J. Kroeger ◽  
M. I. Hossain ◽  
K. Mahmoud ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Carbon Nanotube ◽  
Frequency Band ◽  
Electromagnetic Interference ◽  
High Frequency ◽  
High Electrical Conductivity ◽  
High Frequency Band ◽  
High Demand ◽  
Extremely High Frequency ◽  
Minimal Thickness

Materials offering excellent mechanical flexibility, high electrical conductivity and electromagnetic interference (EMI) attenuation with minimal thickness are in high demand, particularly if they can be easily processed into films.

High frequency band limits in spectral analysis of heart rate variability in preterm infants

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Hadas Israeli-Mendlovic ◽  
Joseph Mendlovic ◽  
Luba Zuk ◽  
Michal Katz-Leurer
Keyword(s):  
Preterm Infants ◽  
High Frequency ◽  
Neonatal Intensive Care ◽  
Breathing Rate ◽  
Frequency Bandwidth ◽  
High Frequency Band ◽  
Constant Frequency ◽  
Band Power ◽  
The Time Domain ◽  
Electrocardiogram Ecg

Abstract Objectives The current study aims to assess different high-frequency (HF) band power calculations based on different frequency bandwidth values, and compare them with the time domain the root mean square of successive RR differences (RMSSD) value in preterm infants. Methods At week 32, electrocardiogram (ECG) and breathing rate (BR) were recorded for 24 h on 30 preterm infants born between 28 and 32 weeks. The recording held in the neonatal intensive care unit without any interruption of routine. Results The median 24 h BR was 40–78 breaths per minute. The RMSSD was highly and positively correlated with frequency bands that were based on each preterms BR range, or on a constant frequency with band limits of 0.4–2 Hz. Conclusions At week 32, HF band Hz limits should be calculated based on each child’s breathing rate, generally between 0.4 and 2 Hz.

scholarly journals A Compact Printed Monopole Antenna for WiMAX/WLAN and UWB Applications

2018 ◽  
Vol 10 (12) ◽  
pp. 122 ◽  
Author(s):  
Zubin Chen ◽  
Baijun Lu ◽  
Yanzhou Zhu ◽  
Hao Lv
Keyword(s):  
Frequency Band ◽  
High Frequency ◽  
Field Work ◽  
Monopole Antenna ◽  
Center Frequency ◽  
High Frequency Band ◽  
Work Requirements ◽  
Printed Monopole Antenna ◽  
Printed Monopole ◽  
Uwb Applications

In this paper, a printed monopole antenna design for WiMAX/WLAN applications in cable-free self-positioning seismograph nodes is proposed. Great improvements were achieved in miniaturizing the antenna and in widening the narrow bandwidth of the high-frequency band. The antenna was fed by a microstrip gradient line and consisted of a triangle, an inverted-F shape, and an M-shaped structure, which was rotated 90° counterclockwise to form a surface-radiating patch. This structure effectively widened the operating bandwidth of the antenna. Excitation led to the generation of two impedance bands of 2.39–2.49 and 4.26–7.99 GHz for a voltage standing wave ratio of less than 2. The two impedance bandwidths were 100 MHz, i.e., 4.08% relative to the center frequency of 2.45 GHz, and 3730 MHz, i.e., 64.31% relative to the center frequency of 5.80 GHz, covering the WiMAX high-frequency band (5.25–5.85 GHz) and the WLAN band (2.4/5.2/5.8). This article describes the design details of the antenna and presents the results of both simulations and experiments that show good agreement. The proposed antenna meets the field-work requirements of cable-less seismograph nodes.

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