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Acceleration forces in pilots

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https://www.readbyqxmd.com/read/28720183/g-loc-warning-algorithms-based-on-emg-features-of-the-gastrocnemius-muscle
#1
Sungho Kim, Taehwan Cho, Yongkyun Lee, Hyojin Koo, Booyong Choi, Dongsoo Kim
BACKGROUND: G-induced loss of consciousness (G-LOC) is mainly caused by failure to sustain an oxygenated blood supply to the pilot's brain because of the sudden acceleration in the direction of the +Gz axis, and is considered a critical safety issue. The purpose of this study was to develop G-LOC warning algorithms based on monitoring electromyograms (EMG) of the gastrocnemius muscle on the calf. METHODS: EMG data was retrieved from a total of 67 pilots and pilot trainees of the Korean Air Force during high-G training on a human centrifugal simulator...
August 1, 2017: Aerospace Medicine and Human Performance
https://www.readbyqxmd.com/read/28539143/incidence-of-g-induced-loss-of-consciousness-and-almost-loss-of-consciousness-in-the-royal-air-force
#2
Ellen Slungaard, Judith McLeod, Nicholas D C Green, Amit Kiran, Di J Newham, Stephen D R Harridge
INTRODUCTION: Exposure to sustained +Gz acceleration with inadequate G protection can result in G-induced loss of consciousness (G-LOC) or almost loss of consciousness (A-LOC). The UK Royal Air Force (RAF) last conducted a survey of G-LOC within their military aircrew in 2005 with interventions subsequently introduced. The aim of this study was to repeat the 2005 survey in order to evaluate the impact of those interventions. METHODS: An anonymous questionnaire requesting details of G-LOC and A-LOC events was mailed to all RAF pilots (N = 1878) and weapons systems operators (WSOs) (N = 473), irrespective of aircraft currently flown...
June 1, 2017: Aerospace Medicine and Human Performance
https://www.readbyqxmd.com/read/28430608/adrenalectomy-abolishes-hypergravity-induced-gastric-acid-hyposecretion
#3
Kiyong Na, Hyun-Soo Kim
Jet fighter pilots experience high gravitational acceleration forces in the cephalocaudal direction (+Gz), causing severe stress. Stress affects different physiological functions of the gastrointestinal tract. Although the effects of exposure to hypergravity on cardiovascular and cerebral functions have been the subject of numerous studies, crucial information regarding potential pathophysiological alterations following hypergravity exposure in the gastrointestinal tract is lacking. We recently documented a significant decrease in gastric secretory activity in rats after acute exposure to hypergravity...
May 9, 2017: Oncotarget
https://www.readbyqxmd.com/read/28323584/evidence-for-gz-adaptation-observed-with-wearable-biosensors-during-high-performance-jet-flight
#4
G Merrill Rice, Dallas Snider, Jeffrey L Moore, J Timothy Lavan, Rich Folga, Thomas B VanBrunt
INTRODUCTION: Few studies have evaluated physiological responses to high acceleration forces during actual flight and to our knowledge no normative data has been acquired by technologies such as wearable biosensors during high performance jet aircraft operations. METHODS: In-flight physiological data from an FDA cleared portable triaxial accelerometer and bio-sensor were observed from five active duty F-18 pilots of the Naval Flight Demonstration Squadron (Blue Angels)...
December 1, 2016: Aerospace Medicine and Human Performance
https://www.readbyqxmd.com/read/28225689/sex-differences-in-anthropometrics-and-heading-kinematics-among-division-i-soccer-athletes
#5
Abigail C Bretzin, Jamie L Mansell, Ryan T Tierney, Jane K McDevitt
BACKGROUND: Soccer players head the ball repetitively throughout their careers; this is also a potential mechanism for a concussion. Although not all soccer headers result in a concussion, these subconcussive impacts may impart acceleration, deceleration, and rotational forces on the brain, leaving structural and functional deficits. Stronger neck musculature may reduce head-neck segment kinematics. HYPOTHESIS: The relationship between anthropometrics and soccer heading kinematics will not differ between sexes...
March 2017: Sports Health
https://www.readbyqxmd.com/read/27916853/a-pilot-study-of-individual-muscle-force-prediction-during-elbow-flexion-and-extension-in-the-neurorehabilitation-field
#6
Jiateng Hou, Yingfei Sun, Lixin Sun, Bingyu Pan, Zhipei Huang, Jiankang Wu, Zhiqiang Zhang
This paper proposes a neuromusculoskeletal (NMS) model to predict individual muscle force during elbow flexion and extension. Four male subjects were asked to do voluntary elbow flexion and extension. An inertial sensor and surface electromyography (sEMG) sensors were attached to subject's forearm. Joint angle calculated by fusion of acceleration and angular rate using an extended Kalman filter (EKF) and muscle activations obtained from the sEMG signals were taken as the inputs of the proposed NMS model to determine individual muscle force...
November 29, 2016: Sensors
https://www.readbyqxmd.com/read/27849511/hiatal-hernia-as-the-cause-of-g-induced-abdominal-pain
#7
Scott B Hughey, Lauren H Mattingly
Sliding hiatal hernias are common and affect approximately 10% to 80% of the general population. The condition typically presents with reflux-type symptoms and is diagnosed either with imaging or endoscopy. In this case, the hernia presented as G-induced abdominal pain. The patient was an F-18 pilot who experienced worsening epigastric abdominal pain proportionate to the amount of accelerative force experienced. The pain would occur at approximately 3 Gs and increase beyond that. The patient was asymptomatic at rest and denied any dysphagia or reflux symptoms...
November 2016: Military Medicine
https://www.readbyqxmd.com/read/27834560/very-heavy-sled-training-for-improving-horizontal-force-output-in-soccer-players
#8
Jean-Benoît Morin, George Petrakos, Pedro Jimenez-Reyes, Scott R Brown, Pierre Samozino, Matt R Cross
Sprint running acceleration is a key feature of physical performance in team sports, and recent literature shows that the ability to generate large magnitudes of horizontal ground reaction force and mechanical effectiveness of force application are paramount. We tested the hypothesis that very-heavy loaded sled sprint training would induce an improvement in horizontal force production, via an increased effectiveness of application. Training-induced changes in sprint performance and mechanical outputs were computed using a field method based on velocity-time data, before and after an 8-week protocol (16 sessions of 10x20-m sprints)...
November 11, 2016: International Journal of Sports Physiology and Performance
https://www.readbyqxmd.com/read/27816900/gait-initiation-is-impaired-in-subjects-with-parkinson-s-disease-in-the-off-state-evidence-from-the-analysis-of-the-anticipatory-postural-adjustments-through-wearable-inertial-sensors
#9
Gianluca Bonora, Martina Mancini, Ilaria Carpinella, Lorenzo Chiari, Fay B Horak, Maurizio Ferrarin
People with Parkinson's disease (PD) typically demonstrate impaired anticipatory postural adjustments (APAs) that shift the body center of mass forward (imbalance) and over the stance leg (unloading) prior to gait initiation. APAs are known to be smallest when people with PD are in their OFF-medication state compared to ON-medication or healthy controls. The aim of this pilot study is to validate a previously developed method for the assessment of gait initiation on PD patients in OFF state with body-worn, inertial sensors...
January 2017: Gait & Posture
https://www.readbyqxmd.com/read/27662347/pitch-plane-angular-displacement-perception-during-helicopter-flight-and-gondola-centrifugation
#10
Arne Tribukait, Eddie Bergsten, Ola Eiken
BACKGROUND: During hovering with a helicopter, an involuntary change in attitude (during brownout) results in reduced lifting force and a horizontal acceleration component. This movement pattern is difficult to perceive via the otolith organs. If the angular displacement occurs rapidly, it will, however, activate the semicircular canals. The major aim of this study was to establish to what extent pitch-plane angular displacements can be perceived based on canal information when there is no tilt stimulus to the otoliths...
2016: Aerospace Medicine and Human Performance
https://www.readbyqxmd.com/read/27255878/cerebral-oxygenation-and-acceleration-in-pediatric-and-neonatal-interfacility-transport
#11
Michael E Valente, Judy A Sherif, Colleen G Azen, Phung K Pham, Calvin G Lowe
OBJECTIVE: The purpose of this study is to measure peak acceleration forces during interfacility transport; examine whether drops in cerebral oxygenation occurred; and test the associations between cerebral oxygenation, acceleration, and patient positioning. METHODS: A cerebral oximeter (INVOS-5100C; Somanetics, Minneapolis, MN) monitored regional saturation of oxygen (rSO2 [cerebral oxygenation]) in pediatric and neonatal patients (N = 24) transported between facilities by ground ambulance, helicopter, or fixed wing aircraft...
May 2016: Air Medical Journal
https://www.readbyqxmd.com/read/27034749/use-of-leukocyte-and-platelet-rich-fibrin-l-prf-in-periodontally-accelerated-osteogenic-orthodontics-paoo-clinical-effects-on-edema-and-pain
#12
Francisco Munoz, Constanza Jiménez, Daniela Espinoza, Alain Vervelle, Jacques Beugnet, Ziyad Haidar
BACKGROUND: Demand for shorter treatment time is common in orthodontic patients. Periodontally Accelerated Osteogenic Orthodontics (PAOO) is a somewhat new surgical procedure which allows faster tooth movement via combining orthodontic forces with corticotomy and grafting of alveolar bone plates. Leukocyte and Platelet-Rich Fibrin (L-PRF) possess hard- and soft-tissue healing properties. Further, evidence of pain-inhibitory and anti-inflammatory potential is growing. Therefore, this study explores the feasibility, intra- and post-operative effects of using L-PRF in PAOO in terms of post-operative pain, inflammation, infection and post-orthodontic stability...
April 2016: Journal of Clinical and Experimental Dentistry
https://www.readbyqxmd.com/read/27007513/effect-of-centrifuge-test-on-blood-serum-lipids-index-of-cadet-pilots
#13
Zbigniew Wochyński, Krzysztof Kowalczuk, Marek Kłossowski, Krzysztof A Sobiech
INTRODUCTION AND OBJECTIVE: This study aimed at investigating the relationship between the lipid index (WS) in the examined cadets and duration of exposure to +Gz in the human centrifuge. MATERIALS AND METHODS: The study involved 19 first-year cadets of the Polish Air Force Academy in Dęblin. Tests in the human centrifuge were repeated twice, i.e. prior to (test I) and 45 days after (test II). After exposure to +Gz, the examined cadets were divided into 2 groups...
2016: Annals of Agricultural and Environmental Medicine: AAEM
https://www.readbyqxmd.com/read/26791405/impairment-of-sprint-mechanical-properties-in-an-actual-soccer-match-a-pilot-study
#14
Ryu Nagahara, Jean-Benoit Morin, Masaaki Koido
PURPOSE: To assess soccer-specific impairment of mechanical properties in accelerated sprinting and its relation with activity profiles during an actual match. METHODS: Thirteen male field players completed 4 sprint measurements, wherein running speed was obtained using a laser distance-measurement system, before and after the 2 halves of 2 soccer matches. Macroscopic mechanical properties (theoretical maximal horizontal force [F0], maximal horizontal sprinting power [Pmax], and theoretical maximal sprinting velocity [V0]) during the 35-m sprint acceleration were calculated from speed-time data...
October 2016: International Journal of Sports Physiology and Performance
https://www.readbyqxmd.com/read/26737905/detection-of-g-induced-loss-of-consciousness-g-loc-prognosis-through-emg-monitoring-on-gastrocnemius-muscle-in-flight
#15
Booyong Choi, Yongkyun Lee, Taehwan Cho, Hyojin Koo, Dongsoo Kim
G-Induced Loss of Consciousness (G-LOC) is mainly caused by the sudden acceleration in the direction of +Gz axis from the fighter pilots, and is considered as an emergent situation of which fighter pilots are constantly aware. In order to resist against G-LOC, fighter pilots are subject to run Anti-G straining maneuver (AGSM), which includes L-1 respiration maneuvering and muscular contraction of the whole body. The purpose of this study is to create a G-LOC warning alarm prior to G-LOC by monitoring the Electromyogram (EMG) of the gastrocnemius muscle on the calf, which goes under constant muscular contraction during the AGSM process...
August 2015: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/26630055/scrotal-hematoma-precipitated-by-centrifuge-training-in-a-fighter-pilot-with-an-asymptomatic-varicocele
#16
Liyona Kampel, Eyal Klang, Harry Winkler, Barak Gordon, Yael Frenkel-Nir, Yifat Erlich Shoam
BACKGROUND: Varicocele is quite common in the general population, affecting up to 15% of men. It is not considered disqualifying for the pilot's training program of the Israeli Air Force as long as there are no related symptoms or associated pathologies. During combat flight, increased venous pressure due to acceleration forces and anti-G straining maneuvers, used to counteract high gravitational G forces, can theoretically aggravate the venous blood pooling in varicocele, leading to rupture...
December 2015: Aerospace Medicine and Human Performance
https://www.readbyqxmd.com/read/26465294/enhanced-phosphorus-removal-by-microbial-collaborating-sponge-iron
#17
Ya'e Wang, Jie Li, Siyuan Zhai, Zhiyong Wei, Juanjuan Feng
The collaborative and mutually reinforcing phosphorus removal in domestic wastewater in a sponge iron and microorganisms system was studied through a laboratory and a pilot scale experiment. The results showed that the total phosphorus concentration of the effluent of less than 0.5 mg/L could be achieved. The results also support that the biochemical reaction accelerated the iron electrochemical corrosion. As a driving force, iron bacteria strengthened the chemical oxidation of Fe(II) to Fe(III). The chemical precipitation of Fe(III) is the main form of phosphorus removal...
2015: Water Science and Technology: a Journal of the International Association on Water Pollution Research
https://www.readbyqxmd.com/read/26387895/in-flight-study-of-helmet-mounted-symbology-system-concepts-in-degraded-visual-environments
#18
Bob Cheung, Gregory Craig, Brad Steels, Robert Sceviour, Vaughn Cosman, Sion Jennings, Peter Holst
BACKGROUND: During approach and departure in rotary wing aircraft, a sudden loss of external visual reference precipitates spatial disorientation. METHODS: There were 10 Royal Canadian Air Force (RCAF) Griffon pilots who participated in an in-flight investigation of a 3-dimensional conformal Helmet Display Tracking System (HDTS) and the BrownOut Symbology System (BOSS) aboard an Advanced System Research Aircraft. For each symbology system, pilots performed a two-stage departure followed by a single-stage approach...
August 2015: Aerospace Medicine and Human Performance
https://www.readbyqxmd.com/read/26059242/pilot-safety-study-of-intrabronchial-instillation-of-bone-marrow-derived-mononuclear-cells-in-patients-with-silicosis
#19
Marcelo M Morales, Sérgio A L Souza, Luiz Paulo Loivos, Marina A Lima, Amir Szklo, Leandro Vairo, Taís H K Brunswick, Bianca Gutfilen, Miquéias Lopes-Pacheco, Alberto J Araújo, Alexandre P Cardoso, Regina C Goldenberg, Patricia R M Rocco, Lea M B Fonseca, José R Lapa e Silva
BACKGROUND: Silicosis is an occupational disease for which no effective treatment is currently known. Systemic administration of bone marrow-derived mononuclear cells (BMDMCs) has shown to be safe in lung diseases. However, so far, no studies have analyzed whether bronchoscopic instillation of autologous BMDMCs is a safe route of administration in patients with silicosis. METHODS: We conducted a prospective, non-randomized, single-center longitudinal study in five patients...
June 11, 2015: BMC Pulmonary Medicine
https://www.readbyqxmd.com/read/26048095/pressure-effects-on-the-nose-by-an-in-flight-oxygen-mask-during-simulated-flight-conditions
#20
J Rieneke C Schreinemakers, C Boer, P C G M van Amerongen, M Kon
BACKGROUND: Dutch F-16 fighter pilots experience oxygen mask inflicted nasal trauma, including discomfort, pain, skin abrasions, bruises and bone remodelling. Pressure and shear forces on the nose might contribute to causing these adverse effects. In this study, it was evaluated how flight conditions affected the exerted pressure, and whether shear forces were present. METHODS: The pressure exerted by the oxygen mask was measured in 20 volunteers by placing pressure sensors on the nose and chin underneath the mask...
December 2016: Journal of the Royal Army Medical Corps
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