The impact of head orientation on multi-segmental torso coordination during the transition from sitting to standing

2010 ◽  
Author(s):  
Molly B. Johnson ◽  
Richard E. A. Van Emmerik
Keyword(s):  
Head Orientation ◽  
The Impact

scholarly journals A Two Joint Neck Model to Identify Malposition of the Head Relative to the Thorax

Sensors ◽  
2021 ◽  
Vol 21 (9) ◽  
pp. 3297
Author(s):  
Philipp M. Schmid ◽  
Christoph M. Bauer ◽  
Markus J. Ernst ◽  
Bettina Sommer ◽  
Lars Lünenburger ◽  
...  
Keyword(s):  
Neck Pain ◽  
Body Height ◽  
Biomechanical Model ◽  
The Body ◽  
Head Orientation ◽  
Neck Length ◽  
Proposed Model ◽  
Biofeedback System ◽  
Simple Measurement ◽  
The Impact

Neck pain is a frequent health complaint. Prolonged protracted malpositions of the head are associated with neck pain and headaches and could be prevented using biofeedback systems. A practical biofeedback system to detect malpositions should be realized with a simple measurement setup. To achieve this, a simple biomechanical model representing head orientation and translation relative to the thorax is introduced. To identify the parameters of this model, anthropometric data were acquired from eight healthy volunteers. In this work we determine (i) the accuracy of the proposed model when the neck length is known, (ii) the dependency of the neck length on the body height, and (iii) the impact of a wrong neck length on the models accuracy. The resulting model is able to describe the motion of the head with a maximum uncertainty of 5 mm only. To achieve this high accuracy the effective neck length must be known a priory. If however, this parameter is assumed to be a linear function of the palpable neck length, the measurement error increases. Still, the resulting accuracy can be sufficient to identify and monitor a protracted malposition of the head relative to the thorax.

The Impact of Maternal Voice on the Fetus: A Systematic Review

2019 ◽  
Vol 15 (3) ◽  
pp. 196-206 ◽  
Author(s):  
Maria Eduarda Salgado Carvalho ◽  
João Manuel Rosado de Miranda Justo ◽  
Maya Gratier ◽  
Helena Maria Ferreira Rodrigues da Silva
Keyword(s):  
Systematic Review ◽  
Mouth Opening ◽  
Head Orientation ◽  
New Paradigm ◽  
Surrogate Mothers ◽  
Nutritive Sucking ◽  
Brain Responses ◽  
Maternal Voice ◽  
Acoustic Conditions ◽  
The Impact

Background: Studies have shown pre-natal memory underlining the ability of newborns to discriminate maternal vs. other voices and to recognize linguistic stimuli presented prenatally by the mother. The fetus reacts to maternal voice at the end of gestation but it is important to clarify the indicators and conditions of these responses. Objective: To understand the state of the art concerning: 1) indicators of fetal reactions to maternal voice vs. other voices; 2) conditions of maternal voice required to obtain fetal response, 3) neonatal recognition of maternal voice and of linguistic material presented prenatally and 4) obstetric and behavioral maternal conditions compromising fetal ability to discriminate between maternal and other female voices. Method: Systematic review using EBSCO, WEBSCIENCE and MEDLINE. Eligibility: studies with maternal voice delivered before birth as stimulus and with fetal or neonatal behavior as responses. Results: Fetal responses to maternal voice are observed through fetal cardiac, motor (fetal yawning decrease, mouth opening, fetal body movements) and brain responses (activation of the lower bank of the left temporal lobe). Newborns’ head orientation and non-nutritive sucking are shown as being neonatal indicators. Conclusion: Gestational age, baseline measures (fetal state, acoustic conditions and pre-stimulus time) and obstetrical conditions may enable or compromise fetal discrimination between maternal and other voices. The role of maternal voice for prenatal human bonding needs to be discussed according to different maternity conditions such as surrogate mothers. A new paradigm is suggested; the focus of research should be on maternal-fetal interaction under the presence of maternal voice.</P>

scholarly journals DYNAMICS RESPONSE OF THE HUMAN HEAD DURING DRYWALL IMPACT

2021 ◽  
Vol 57 (2) ◽  
pp. 136-144
Author(s):  
Michael A.K. Liebschner ◽  
◽  
Leroy R. Waite ◽  
Keyword(s):  
Composite Structures ◽  
Block Design ◽  
Human Head ◽  
Study Data ◽  
Head Orientation ◽  
Drop Height ◽  
Study Objective ◽  
Randomized Block Design ◽  
Dynamics Response ◽  
The Impact

Little experimental data has been reported on the biomechanics of head collisions with drywall sections. The dynamics of head collisions with rigid structures are well documented. However, impacts with compliant, composite structures are more difficult to analyze. The study objective was to correlate the severity of a head impact with damage to the drywall. A human head analog was instrumented with a tri-axial accelerometer and a uniaxial load cell was placed along the cervical spine axis. A randomized block design of drop height and head orientation was utilized. The test results indicated a primarily linear correlation between drop height and peak head acceleration, as well as correlation between drop height and the geometry of the indentation to the drywall. Head posture had little influence on wall damage, however, head extension resulted in a stiffer head-spine complex compared to a flexed posture. A two-factor ANOVA determined a statistically significant correlation between damage severity and impact velocity. The results obtained can be used by accident reconstructionists to approximate the impact severity of a head impacting drywall. The study data are limited to drywall sections of known, similar geometry, and does not apply to scenarios with a support beam directly beneath the drywall. Further studies are needed to investigate additional head postures.

Effects of Head Orientation on Gaze Perception: How Positive Congruency Effects Can be Reversed

2008 ◽  
Vol 61 (3) ◽  
pp. 491-504 ◽  
Author(s):  
Paola Ricciardelli ◽  
Jon Driver
Keyword(s):  
Time Pressure ◽  
Gaze Direction ◽  
Head Orientation ◽  
Sources Of Information ◽  
Gaze Perception ◽  
Visible Part ◽  
The Face ◽  
Orientation Cues ◽  
The Impact ◽  
Eye Region

Several past studies have considered how perceived head orientation may be combined with perceived gaze direction in judging where someone else is attending. In three experiments we tested the impact of different sources of information by examining the role of head orientation in gaze-direction judgements when presenting: (a) the whole face; (b) the face with the nose masked; (c) just the eye region, removing all other head-orientation cues apart from some visible part of the nose; or (d) just the eyes, with all parts of the nose masked and no head orientation cues present other than those within the eyes themselves. We also varied time pressure on gaze direction judgements. The results showed that gaze judgements were not solely driven by the eye region. Gaze perception can also be affected by parts of the head and face, but in a manner that depends on the time constraints for gaze direction judgements. While “positive” congruency effects were found with time pressure (i.e., faster left/right judgements of seen gaze when the seen head deviated towards the same side as that gaze), the opposite applied without time pressure.

scholarly journals The impact of farrowing room noise on sows’ reactivity to piglets

2018 ◽  
Vol 3 (1) ◽  
pp. 175-184
Author(s):  
Nichole M Chapel ◽  
J Scott Radcliffe ◽  
Kara R Stewart ◽  
Jeffrey R Lucas ◽  
Donald C Lay
Keyword(s):  
Mechanical Ventilation ◽  
Drinking Behavior ◽  
Video Recording ◽  
Video Observation ◽  
Head Orientation ◽  
Fan Noise ◽  
Acoustic Environment ◽  
The Impact ◽  
Behavior Observations

Abstract Despite much interest in sow welfare, the impact of the acoustic environment on sow reactivity to her piglets is rarely considered. The objective of this study was to understand the impact of noise produced by mechanical ventilation and other sows on a sow’s reactivity to her piglets. Sows were farrowed in one of three environments: 1) with eight other sows exposed to constant fan noise (GROUP-FAN; n = 10), 2) alone with fan noise present (ISO-FAN; n = 10), and 3) alone without fans running (ISO-QUIET; n = 10). Sows were subjected for 5 min to a piglet removal event (REMOVAL) by an unknown handler twice, at 24 and 48 h postfarrowing. During a REMOVAL, sows were observed via video recording for changes in posture, eating and drinking behavior, and head orientation. Audio was recorded to quantify vocalizations by the sow. Once piglets were returned, sows underwent further behavior observations for 10 min (RETURN), resulting in approximately 15 min of total video observation. Sows were classified as young (second and third parity) and old (fifth parity and older). The YOUNG sows tended to be more Alert (looking toward the handler or their piglets) during REMOVE than OLD sows (P = 0.07; 2.01 and 1.33, respectively). The ISO-FAN sows vocalized the loudest during REMOVAL (P &lt; 0.001) with ISO-QUIET sows performing the quietest vocalizations (GROUP-FAN: 72.22 ± 1.06 dB; ISO-FAN: 73.61 ± 1.07 dB; ISO-QUIET: 67.41 ± 0.99 dB). During RETURN, YOUNG sows spent more time sitting than OLD sows (P &lt; 0.01; 7.48 ± 1.6% and 0.91 ± 1.8%, respectively). The ISO-QUIET sows tended to have more posture changes during the RETURN with ISO-FAN having the least changes (P = 0.06; GROUP-FAN: 1.23 ± 0.4; ISO-FAN: 0.44 ± 0.3; ISO-QUIET: 1.61 ± 0.4). Finally, sows decreased the amount of time Alert in the second RETURN (P = 0.03; first: 3.9 ± 0.6%; second: 2.5 ± 0.6%). Overall, sows acclimated to the removal and return events with decreased vocalizations and decreased Alert behaviors in the second REMOVAL and RETURN. Additionally, YOUNG sows performed more active behaviors than OLD sows, indicating that sows may become less interested in or cannot hear their piglets as they age. Finally, there is some indication that ventilation presence has an effect on sow–piglet communication with ISO-FAN sows having the loudest vocalizations when compared with sows without ventilation noise, indicating that ventilation noise may be a possible competitor with a sow’s ability to communicate with her piglets.

Formation of Lunar Craters and Bright Rays as a Result of Meteorite Impacts

1962 ◽  
Vol 14 ◽  
pp. 415-418
Author(s):  
K. P. Stanyukovich ◽  
V. A. Bronshten
Keyword(s):  
Explosive Charge ◽  
The Moon ◽  
Meteorite Impacts ◽  
The Earth ◽  
Lunar Craters ◽  
The Impact

The phenomena accompanying the impact of large meteorites on the surface of the Moon or of the Earth can be examined on the basis of the theory of explosive phenomena if we assume that, instead of an exploding meteorite moving inside the rock, we have an explosive charge (equivalent in energy), situated at a certain distance under the surface.

The Geosciences Applied to Lunar Exploration

1962 ◽  
Vol 14 ◽  
pp. 169-257 ◽  
Author(s):  
J. Green
Keyword(s):  
Lunar Surface ◽  
Probable Mechanism ◽  
Point Of View ◽  
Lunar Exploration ◽  
Geological Model ◽  
Apply Geophysics ◽  
Surface Features ◽  
The Impact

The term geo-sciences has been used here to include the disciplines geology, geophysics and geochemistry. However, in order to apply geophysics and geochemistry effectively one must begin with a geological model. Therefore, the science of geology should be used as the basis for lunar exploration. From an astronomical point of view, a lunar terrain heavily impacted with meteors appears the more reasonable; although from a geological standpoint, volcanism seems the more probable mechanism. A surface liberally marked with volcanic features has been advocated by such geologists as Bülow, Dana, Suess, von Wolff, Shaler, Spurr, and Kuno. In this paper, both the impact and volcanic hypotheses are considered in the application of the geo-sciences to manned lunar exploration. However, more emphasis is placed on the volcanic, or more correctly the defluidization, hypothesis to account for lunar surface features.

Asteroid and Comet Impact Speeds upon Mars: Significance for Panspermia and the Supply of Organics

1997 ◽  
Vol 161 ◽  
pp. 197-201 ◽  
Author(s):  
Duncan Steel
Keyword(s):  
Probability Distributions ◽  
Regions Of Interest ◽  
Significant Fraction ◽  
Organic Chemicals ◽  
Impact Speed ◽  
The Mean ◽  
The Impact

AbstractWhilst lithopanspermia depends upon massive impacts occurring at a speed above some limit, the intact delivery of organic chemicals or other volatiles to a planet requires the impact speed to be below some other limit such that a significant fraction of that material escapes destruction. Thus the two opposite ends of the impact speed distributions are the regions of interest in the bioastronomical context, whereas much modelling work on impacts delivers, or makes use of, only the mean speed. Here the probability distributions of impact speeds upon Mars are calculated for (i) the orbital distribution of known asteroids; and (ii) the expected distribution of near-parabolic cometary orbits. It is found that cometary impacts are far more likely to eject rocks from Mars (over 99 percent of the cometary impacts are at speeds above 20 km/sec, but at most 5 percent of the asteroidal impacts); paradoxically, the objects impacting at speeds low enough to make organic/volatile survival possible (the asteroids) are those which are depleted in such species.

Organic Syntheses During the Impact of a Comet with a Gaseous Planet

1997 ◽  
Vol 161 ◽  
pp. 189-195
Author(s):  
Cesare Guaita ◽  
Roberto Crippa ◽  
Federico Manzini
Keyword(s):  
Polymeric Material ◽  
Molecular Form ◽  
Parent Compound ◽  
Blue Filter ◽  
Organic Syntheses ◽  
The Impact

AbstractA large amount of CO has been detected above many SL9/Jupiter impacts. This gas was never detected before the collision. So, in our opinion, CO was released from a parent compound during the collision. We identify this compound as POM (polyoxymethylene), a formaldehyde (HCHO) polymer that, when suddenly heated, reformes monomeric HCHO. At temperatures higher than 1200°K HCHO cannot exist in molecular form and the most probable result of its decomposition is the formation of CO. At lower temperatures, HCHO can react with NH3 and/or HCN to form high UV-absorbing polymeric material. In our opinion, this kind of material has also to be taken in to account to explain the complex evolution of some SL9 impacts that we observed in CCD images taken with a blue filter.

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