scholarly journals Evaluation of Head and Body Kinematics Experienced During Parachute Opening Shock

2020 ◽  
Author(s):  
Tyler F Rooks ◽  
Brian L Novotny ◽  
Shannon M McGovern ◽  
Andrea Winegar ◽  
Bethany L Shivers ◽  
...  
Keyword(s):  
Musculoskeletal Pain ◽  
Potential Risk ◽  
Angular Rate ◽  
Free Fall ◽  
The Body ◽  
Future Research ◽  
Wing Loading ◽  
Neck Length ◽  
Parachute Canopy ◽  
The U.S

ABSTRACT Introduction The U.S. Army conducts airborne operations in order to insert soldiers into combat. Military airborne operations are physically demanding activities with a unique loading environment compared with normal duties. A significant amount of research surrounding airborne operations has focused on assessing the incidence and type of associated injuries as well as the potential risk factors for injuries. During parachute opening shock and other high-acceleration events (e.g., fixed wing flight or vehicle crashes), the neck may be vulnerable to injury if inertial loads overcome the voluntary muscular control of the cervical spine and soft tissue structures. A recent epidemiological survey of sport skydivers showed that the neck, shoulders, and back were the most frequently reported sites of musculoskeletal pain. In addition, the survey indicated that wing loading (a measure of the jumper’s weight divided by the size of the parachute canopy) was a potential contributing factor for developing musculoskeletal pain. Recently, there have been efforts to measure the severity of parachute opening shock as an additional potential risk factor for injury; however, no studies have measured both head and body accelerations and no studies have measured head or body angular rate during parachute opening shock. The purpose of this study was to measure and characterize the accelerations and angular rates of both the head and body during parachute opening shock as well as investigate potential factors contributing to higher severity opening shock, which may link to the development of musculoskeletal pain or injury. Materials and Methods Data were collected from the U.S. Army Parachute Team, The Golden Knights, under an approved Medical Research and Material Command Institutional Review Board protocol. Subjects were instrumented with a helmet- and body-mounted sensor package, which included three angular rate sensors and three single-axis accelerometers each. Data were collected at 2,500 samples per second. Kruskal-Wallis tests were used to determine if helmet-mounted equipment (e.g., cameras), neck length, neck circumference, or wing loading (the ratio of jump weight to the size of the main parachute canopy) affected the accelerations or angular rates of the head or body. Results A total of 54 jumps conducted by 19 experienced free-fall jumpers were analyzed. For the head, the mean (± SD) resultant accelerations and angular rates were 5.8 (± 1.6) g and 255.9 (± 74.2) degrees per second (deg/s), respectively. For the body, the resultant accelerations and angular rates were 4.3 (± 1.5) g and 181.3 (± 61.2) deg/s, respectively. A wing loading above 1.4 pounds per square foot (lb/ft2) was found to have a significant effect on head (P = .001) and body (P = .001) resultant acceleration as well as body angular rate about the Y-axis (P = .001). Conclusions There is evidence to suggest that wing loading has an influence on individual head and body resultant accelerations. However, no significant effects were found for the other variables (e.g., neck length and circumference, helmet-mounted equipment, etc.). Future research should focus on identifying additional factors that result in changes in accelerations and angular rates of the head and body during parachute opening shock events.

scholarly journals УСТАНОВЛЕНИЕ ОГРАНИЧЕНИЙ ПО МАКСИМАЛЬНЫМ СКОРОСТЯМ ДЕСАНТИРОВАНИЯ С УЧЁТОМ ДЕГРАДАЦИИ ПРОЧНОСТНЫХ ХАРАКТЕРИСТИК МАТЕРИАЛОВ КУПОЛА ПАРАШЮТА. СООБЩЕНИЕ 1. ЗАВИСИМОСТЬ ПРОЧНОСТИ ПАРАШЮТОВ ОТ ДЕГРАДАЦИИ ПРОЧНОСТНЫХ ХАРАКТЕРИСТИК КОНСТРУКЦИОННЫХ МАТЕРИАЛОВ

2019 ◽  
pp. 65-71
Author(s):  
Петр Александрович Фомичев
Keyword(s):  
Initial Conditions ◽  
Free Fall ◽  
The Body ◽  
Design Stage ◽  
Initial Moment ◽  
Safety Factors ◽  
Simplified Approach ◽  
Term Operation ◽  
Parachute Canopy

It is introduced the concept of the degradation coefficients of the parachute canopy power structure materials strength characteristics. These coefficients are defined as the ratio of destructive loads after long-term operation or storage to the original, taken at the design stage. It is noted revealed the dependence of safety factors on degradation factors. It was determined the condition of safety factors equality after the long-term operation and during the design stage. It was shown that the ratio of maximum permissible loads is equal to the degradation coefficient. It was defined as the method for calculating the load on the parachute during deployment. It was applied to the simplified approach proposed by N. A. Lobanov. The following statement was determined according to this approach: a dynamic coefficient equal to two, a method for determining the dangerous section of the dome when assessing the fabric strength, the dependence of the speed at the moment of full filling of the parachute canopy from the generalized empirical coefficient. Characteristics of the standard atmosphere, depending on the height of throwing the aircraft are given by approximating functions. The movement of the body until the parachute opens is given in the form of differential equations with known initial conditions. The equation allows you to find the falling speed at the initial moment of the parachute opening, depending on the delay time. It is given the speed of steady free fall without the introduction of a parachute into the work and with a stabilizing parachute, the landing speed with the main parachute. The dependences of the maximum permissible loads on the dome at the opening moment on the strength degradation factors for the fabric of the dome, lines, and free ends of the suspension system are established. It was proposed the correlations for the maximum allowable speed at the time of the beginning of the parachute opening on the requirements of strength. This speed determines the maximum allowed landing speed for a particular type of parachute after long-term operation or storage.

Questions

2018 ◽  
Author(s):  
James L. Gibson ◽  
Michael J. Nelson
Keyword(s):  
United States ◽  
African Americans ◽  
Supreme Court ◽  
Legal System ◽  
Public Support ◽  
The United States ◽  
Future Research ◽  
White Americans ◽  
Two Factors ◽  
The U.S

We have investigated the differences in support for the U.S. Supreme Court among black, Hispanic, and white Americans, catalogued the variation in African Americans’ group attachments and experiences with legal authorities, and examined how those latter two factors shape individuals’ support for the U.S. Supreme Court, that Court’s decisions, and for their local legal system. We take this opportunity to weave our findings together, taking stock of what we have learned from our analyses and what seem like fruitful paths for future research. In the process, we revisit Positivity Theory. We present a modified version of the theory that we hope will guide future inquiry on public support for courts, both in the United States and abroad.

scholarly journals Music, Politics, and History: An Introduction

2021 ◽  
Vol 60 (2) ◽  
pp. 362-374
Author(s):  
David Kennerley
Keyword(s):  
Sound Studies ◽  
The Body ◽  
Future Research ◽  
Short Article ◽  
Distinctive Features ◽  
Music And Politics ◽  
Introductory Article ◽  
History Of ◽  
Eighteenth And Nineteenth Centuries ◽  
The Relationship

AbstractMusic has been steadily rising up the historical agenda, a product of the emergence of sound studies, the history of the senses, and a mood of interdisciplinary curiosity. This introductory article offers a critical review of how the relationship between music and politics has featured in extant historical writing, from classic works of political history to the most recent scholarship. It begins by evaluating different approaches that historians have taken to music, summarizes the important shifts in method that have recently taken place, and advocates for a performance-centered, contextualized framework that is attentive to the distinctive features of music as a medium. The second half examines avenues for future research into the historical connections between music and politics, focusing on four thematic areas—the body, emotions, space, and memory—and closes with some overarching reflections on music's use as a tool of power, as well as a challenge to it. Although for reasons of cohesion, this short article focuses primarily on scholarship on Britain and Ireland in the eighteenth and nineteenth centuries, its discussion of theory and methods is intended to be applicable to the study of music and political culture across a broad range of periods and geographies.

scholarly journals Involvement of Probiotics and Postbiotics in the Immune System Modulation

Biologics ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 89-110
Author(s):  
Neslihan Yeşilyurt ◽  
Birsen Yılmaz ◽  
Duygu Ağagündüz ◽  
Raffaele Capasso
Keyword(s):  
Immune System ◽  
Pharmaceutical Industry ◽  
Intestinal Microbiota ◽  
Health Benefits ◽  
The Body ◽  
Future Research ◽  
Immune Systems ◽  
Advantages And Disadvantages ◽  
Immune System Modulation ◽  
Molecular Patterns

Intestinal microbiota interacts with other systems, especially the immune system, which is responsible for protecting the body by recognizing “stranger” (pathogen associated molecular patterns-PAMPs) and “danger” (damage-associated molecular patterns-DAMPs) molecular motifs. In this manner, it plays an important role in the pathogenesis of various diseases and health. Despite the use of probiotics that modulate the intestinal microbiota in providing health benefits and in the treatment of diseases, there are some possible concerns about the possibility of developing adverse effects, especially in people with suppressed immune systems. Since probiotics provide health benefits with bioactive compounds, studies are carried out on the use of products containing non-living probiotic microorganisms (paraprobiotics) and/or their metabolites (postbiotics) instead of probiotic products. It is even reported that these microbial compounds have more immunomodulatory activities than living microorganisms via some possible mechanism and eliminates some disadvantages of probiotics. Considering the increasing use of functional foods in health and disease, further studies are needed with respect to the benefits and advantages of parabiotic and/or postbiotic use in the food and pharmaceutical industry as well as immune system modulation. Although probiotics have been extensive studied for a long time, it seems that postbiotics are promising tools for future research and applications according to the recent literature. This review aimed to evaluate the interaction of probiotics and postbiotics with the immune systems and also their advantages and disadvantages in the area of food-pharmaceutical industry and immune system modulation.

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.

Understanding of Aviation Safety Pictograms among Respondents from Europe and the U.S.

1996 ◽  
Vol 40 (16) ◽  
pp. 820-824 ◽  
Author(s):  
Florian Jentsch
Keyword(s):  
Native Language ◽  
Safety Information ◽  
Aviation Safety ◽  
Future Research ◽  
Research Needs ◽  
Native Languages ◽  
Language Groups ◽  
Passenger Safety ◽  
Pictorial Representations ◽  
The U.S

Conveying safety information to aircraft passengers is an important task for the designers of aircraft passenger safety information cards. Since the information must be understood by all passengers, regardless of native language or nationality, many designers use pictorial representations that are considered “culture free.” The current study investigated the comprehension of 13 pictograms from a sample of actual safety cards among participants from four language groups in Europe and the U.S. One-hundred-and-fifty students whose native languages were English (British and U.S.), French, or German, respectively, interpreted 13 pictograms. From their responses, three main conclusions can be drawn: 1. Conveying aviation safety information by pictorial means appears to be largely effective, as indicated by general comprehension levels above 85%. 2. While passengers may get the “essence” of a particular pictogram, it is often difficult for them to recognize specific details. 3. There are relatively small differences in the comprehension levels between participants from different language groups, pointing towards the “universality” of pictograms in conveying safety information. Future research needs to focus on identifying exactly which features of pictograms are most effective in conveying safety information, without introducing cultural or language biases.

Event innovation induced corporate branding

2017 ◽  
Vol 29 (3) ◽  
pp. 862-882 ◽  
Author(s):  
Fiona X. Yang ◽  
Sherry Xiuchang Tan
Keyword(s):  
Corporate Branding ◽  
Structural Equation ◽  
Corporate Image ◽  
The Body ◽  
Equation Modeling ◽  
Future Research ◽  
Event Management ◽  
Content Type ◽  
Body Of Knowledge ◽  
Corporate Loyalty

Purpose This paper aims to empirically investigate how event innovation may induce desirable corporate branding. Design/methodology/approach A survey yielded 280 complete responses from tourists who had attended an event in Macau. Structural equation modeling was used to test the innovation-corporate loyalty framework through perceived event value and corporate image, with a multi-group comparison to examine differences between first-time and repeat customers. Findings The results indicate that innovation is not only the key to value enhancement of the event but also an efficacious instrument of branding the parent company and building corporate loyalty; only product-related innovation has a significant impact on event value; both functional and emotional values induce a more favorable corporate image; and event-induced corporate branding is more effective in securing repeat business than attracting new clientele. Practical implications The findings help hospitality operators and event planners to leverage innovative events for corporate branding and cater to different customer segments by providing distinct marketing strategies. Originality/value The study contributes to the body of knowledge regarding event management and corporate branding and sheds light on future research to explore the initiative and benefit of pushing forward event innovation.

The putative effects of green tea on body fat: an evaluation of the evidence and a review of the potential mechanisms

2011 ◽  
Vol 106 (9) ◽  
pp. 1297-1309 ◽  
Author(s):  
Navamayooran Thavanesan
Keyword(s):  
Weight Loss ◽  
Green Tea ◽  
Body Fat ◽  
Fatty Acid Synthase ◽  
The Body ◽  
Alternative Methods ◽  
Future Research ◽  
Prevalence Of Obesity ◽  
Simultaneous Inhibition

The increase in the prevalence of obesity in recent years has prompted research into alternative methods of modulating body weight and body fat. The last decade has reflected this with a surge in studies investigating the potential of green tea as a natural agent of weight loss, with a view to confirming and elucidating the mechanisms underlying its effect on the body. Currently, it is widely believed that the polyphenolic components present in green tea have an anti-obesogenic effect on fat homeostasis, by increasing thermogenesis or reducing fat absorption among other ways. The data published to date, however, are inconsistent, with numerous putative modes of action suggested therein. While several unimodal mechanisms have been postulated, a more plausible explanation of the observed results might involve a multimodal approach. Such a mechanism is suggested here, involving simultaneous inhibition of the enzymes catechol-O-methyltransferase, acetyl-CoA carboxylase, fatty acid synthase and impeding absorption of fat via the gut. An evaluation of the available evidence supports a role of green tea in weight loss; however the extent of the effects obtained is still subject to debate, and requires more objective quantification in future research.

scholarly journals Cyber-Flirting: An Examination of Men's and Women's Flirting Behaviour Both Offline and on the Internet

2004 ◽  
Vol 21 (2) ◽  
pp. 115-126 ◽  
Author(s):  
Monica T. Whitty
Keyword(s):  
Physical Attractiveness ◽  
The Body ◽  
Nonverbal Cues ◽  
Future Research ◽  
The Internet ◽  
Research Needs ◽  
Men And Women ◽  
Face To Face ◽  
Online Interactions

AbstractWhile flirting is a relatively underresearched area within psychology, even less is known about how people cyber-flirt. This paper explores how often individuals flirt offline compared to online. Moreover, it attempts to examine how men and women flirt within these different spaces. Five thousand, six hundred and ninety-seven individuals, of which 3554 (62%) were women and 2143 (38%) were men, completed a survey about their flirting behaviour both in face-to-face interactions and in chatrooms. The first hypothesis, which stated that the body would be used to flirt with as frequently online as offline, was partly supported. However, it was found that individuals downplayed the importance of physical attractiveness online. Women flirted by displaying nonverbal signals (offline) or substitutes for nonverbal cues (online), to a greater extent than men. In chatrooms men were more likely than women to initiate contact. It is concluded that cyber-flirting is more than simply a meeting of minds and that future research needs to consider the role of the body in online interactions.

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