Head-impact mechanisms in men's and women's collegiate ice hockey.

Science.gov (United States)

Wilcox, Bethany J; Machan, Jason T; Beckwith, Jonathan G; Greenwald, Richard M; Burmeister, Emily; Crisco, Joseph J

2014-01-01

Concussion injury rates in men's and women's ice hockey are reported to be among the highest of all collegiate sports. Quantification of the frequency of head impacts and the magnitude of head acceleration as a function of the different impact mechanisms (eg, head contact with the ice) that occur in ice hockey could provide a better understanding of this high injury rate. To quantify and compare the per-game frequency and magnitude of head impacts associated with various impact mechanisms in men's and women's collegiate ice hockey players. Cohort study. Collegiate ice hockey rink. Twenty-three men and 31 women from 2 National Collegiate Athletic Association Division I ice hockey teams. We analyzed magnitude and frequency (per game) of head impacts per player among impact mechanisms and between sexes using generalized mixed linear models and generalized estimating equations to account for repeated measures within players. Participants wore helmets instrumented with accelerometers to allow us to collect biomechanical measures of head impacts sustained during play. Video footage from 53 games was synchronized with the biomechanical data. Head impacts were classified into 8 categories: contact with another player; the ice, boards or glass, stick, puck, or goal; indirect contact; and contact from celebrating. For men and women, contact with another player was the most frequent impact mechanism, and contact with the ice generated the greatest-magnitude head accelerations. The men had higher per-game frequencies of head impacts from contact with another player and contact with the boards than did the women (P < .001), and these impacts were greater in peak rotational acceleration (P = .027). Identifying the impact mechanisms in collegiate ice hockey that result in frequent and high-magnitude head impacts will provide us with data that may improve our understanding of the high rate of concussion in the sport and inform injury-prevention strategies.

Validation of an "Intelligent Mouthguard" Single Event Head Impact Dosimeter.

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Bartsch, Adam; Samorezov, Sergey; Benzel, Edward; Miele, Vincent; Brett, Daniel

2014-11-01

Dating to Colonel John Paul Stapp MD in 1975, scientists have desired to measure live human head impacts with accuracy and precision. But no instrument exists to accurately and precisely quantify single head impact events. Our goal is to develop a practical single event head impact dosimeter known as "Intelligent Mouthguard" and quantify its performance on the benchtop, in vitro and in vivo. In the Intelligent Mouthguard hardware, limited gyroscope bandwidth requires an algorithm-based correction as a function of impact duration. After we apply gyroscope correction algorithm, Intelligent Mouthguard results at time of CG linear acceleration peak correlate to the Reference Hybrid III within our tested range of pulse durations and impact acceleration profiles in American football and Boxing in vitro tests: American football, IMG=1.00REF-1.1g, R2=0.99; maximum time of peak XYZ component imprecision 3.6g and 370 rad/s2; maximum time of peak azimuth and elevation imprecision 4.8° and 2.9°; maximum average XYZ component temporal imprecision 3.3g and 390 rad/s2. Boxing, IMG=1.00REF-0.9 g, R2=0.99, R2=0.98; maximum time of peak XYZ component imprecision 3.9 g and 390 rad/s2, maximum time of peak azimuth and elevation imprecision 2.9° and 2.1°; average XYZ component temporal imprecision 4.0 g and 440 rad/s2. In vivo Intelligent Mouthguard true positive head impacts from American football players and amateur boxers have temporal characteristics (first harmonic frequency from 35 Hz to 79 Hz) within our tested benchtop (first harmonic frequencyIntelligent Mouthguard qualifies as a single event dosimeter in American football and Boxing.

Practice type effects on head impact in collegiate football.

Science.gov (United States)

Reynolds, Bryson B; Patrie, James; Henry, Erich J; Goodkin, Howard P; Broshek, Donna K; Wintermark, Max; Druzgal, T Jason

2016-02-01

OBJECT IVE: This study directly compares the number and severity of subconcussive head impacts sustained during helmet-only practices, shell practices, full-pad practices, and competitive games in a National Collegiate Athletic Association (NCAA) Division I-A football team. The goal of the study was to determine whether subconcussive head impact in collegiate athletes varies with practice type, which is currently unregulated by the NCAA. Over an entire season, a cohort of 20 collegiate football players wore impact-sensing mastoid patches that measured the linear and rotational acceleration of all head impacts during a total of 890 athletic exposures. Data were analyzed to compare the number of head impacts, head impact burden, and average impact severity during helmet-only, shell, and full-pad practices, and games. Helmet-only, shell, and full-pad practices and games all significantly differed from each other (p ≤ 0.05) in the mean number of impacts for each event, with the number of impacts being greatest for games, then full-pad practices, then shell practices, and then helmet-only practices. The cumulative distributions for both linear and rotational acceleration differed between all event types (p football players.

Human papilloma virus: a new risk factor in a subset of head and neck cancers.

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Bisht, Manisha; Bist, Sampan Singh

2011-01-01

Head and neck cancer is the sixth most common malignancy worldwide. Tobacco smoking and alcohol consumption are two well known behavioral risk factors associated with head and neck cancer. Recently, evidence is mounting that infection with human papilloma virus, most commonly human papilloma virus-16 is responsible for a subset of head and neck squamous cell carcinoma especially tumors of tonsillar origin. The molecular pathway used by human papilloma virus to trigger malignant transformation of tissue is different from that of other well known risk factors, i.e. smoking and alcohol, associated with squamous cell carcinoma. Apparently, these subsets of patients with human papilloma virus positive tumor are more likely to have a better prognosis than human papilloma virus negative tumor. Considering this fact, the human papilloma virus infection should be determined in all oropharyngeal cancers since it can have a major impact on the decision making process of the treatment.

Methods That Examine the Extent to Which the Quality of Children's Experiences in Elementary School Moderate the Long-Term Impacts of Head Start

Science.gov (United States)

Mashburn, Andrew J.; Downer, Jason T.

2013-01-01

The goals of the Head Start Impact Study (HSIS) are to: (1) determine the impacts of Head Start on children's school readiness and parental practices that support children's development; and (2) to determine under what circumstances Head Start achieves its greatest impacts and for which children (US Department of Health and Human Services, 2010).…

Effects of Sex and Event Type on Head Impact in Collegiate Soccer

Science.gov (United States)

Reynolds, Bryson B.; Patrie, James; Henry, Erich J.; Goodkin, Howard P.; Broshek, Donna K.; Wintermark, Max; Druzgal, T. Jason

2017-01-01

Background: The effects of head impact in sports are of growing interest for clinicians, scientists, and athletes. Soccer is the most popular sport worldwide, but the burden of head impact in collegiate soccer is still unknown. Purpose: To quantify head impact associated with practicing and playing collegiate soccer using wearable accelerometers. Study Design: Descriptive epidemiological study. Methods: Mastoid patch accelerometers were used to quantify head impact in soccer, examining differences in head impact as a function of sex and event type (practice vs game). Seven female and 14 male collegiate soccer players wore mastoid patch accelerometers that measured head impacts during team events. Data were summarized for each athletic exposure, and statistical analyses evaluated the mean number of impacts, mean peak linear acceleration, mean peak rotational acceleration, and cumulative linear and rotational acceleration, each grouped by sex and event type. Results: There were no differences in the frequency or severity of head impacts between men’s and women’s soccer practices. For men’s soccer, games resulted in 285% more head impacts than practices, but there were no event-type differences in mean impact severity. Men’s soccer games resulted in more head impacts than practices across nearly all measured impact severities, which also resulted in men’s soccer games producing a greater cumulative impact burden. Conclusion: Similar to other sports, men’s soccer games have a greater impact burden when compared with practices, and this effect is driven by the quantity rather than severity of head impacts. In contrast, there were no differences in the quantity or severity of head impacts in men’s and women’s soccer practices. These data could prompt discussions of practical concern to collegiate soccer, such as understanding sex differences in head impact and whether games disproportionately contribute to an athlete’s head impact burden. PMID:28491885

The importance of rotational kinematics in pedestrian head to windshield impacts

NARCIS (Netherlands)

Mordaka, J.; Kleiven, S.; Schijndel-de Nooij, M. van; Lange, R. de; Casanova, L.J.G.; Carter, E.L.; Holst, H. von

2007-01-01

The objective of the present study was to analyze the effect of angular kinematics on head injury in pedestrian head-to-windshield impacts. Three cases of pedestrian head impacts were simulated with FE head and windshield models. The initial impact conditions were obtained from pedestrian accident

Evaluating the "Threshold Theory": Can Head Impact Indicators Help?

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Mihalik, Jason P; Lynall, Robert C; Wasserman, Erin B; Guskiewicz, Kevin M; Marshall, Stephen W

2017-02-01

This study aimed to determine the clinical utility of biomechanical head impact indicators by measuring the sensitivity, specificity, positive predictive value (PV+), and negative predictive value (PV-) of multiple thresholds. Head impact biomechanics (n = 283,348) from 185 football players in one Division I program were collected. A multidisciplinary clinical team independently made concussion diagnoses (n = 24). We dichotomized each impact using diagnosis (yes = 24, no = 283,324) and across a range of plausible impact indicator thresholds (10g increments beginning with a resultant linear head acceleration of 50g and ending with 120g). Some thresholds had adequate sensitivity, specificity, and PV-. All thresholds had low PV+, with the best recorded PV+ less than 0.4% when accounting for all head impacts sustained by our sample. Even when conservatively adjusting the frequency of diagnosed concussions by a factor of 5 to account for unreported/undiagnosed injuries, the PV+ of head impact indicators at any threshold was no greater than 1.94%. Although specificity and PV- appear high, the low PV+ would generate many unnecessary evaluations if these indicators were the sole diagnostic criteria. The clinical diagnostic value of head impact indicators is considerably questioned by these data. Notwithstanding, valid sensor technologies continue to offer objective data that have been used to improve player safety and reduce injury risk.

Drill-specific head impact exposure in youth football practice.

Science.gov (United States)

Campolettano, Eamon T; Rowson, Steven; Duma, Stefan M

2016-11-01

OBJECTIVE Although 70% of football players in the United States are youth players (6-14 years old), most research on head impacts in football has focused on high school, collegiate, or professional populations. The objective of this study was to identify the specific activities associated with high-magnitude (acceleration > 40g) head impacts in youth football practices. METHODS A total of 34 players (mean age 9.9 ± 0.6 years) on 2 youth teams were equipped with helmet-mounted accelerometer arrays that recorded head accelerations associated with impacts in practices and games. Videos of practices and games were used to verify all head impacts and identify specific drills associated with each head impact. RESULTS A total of 6813 impacts were recorded, of which 408 had accelerations exceeding 40g (6.0%). For each type of practice drill, impact rates were computed that accounted for the length of time that teams spent on each drill. The tackling drill King of the Circle had the highest impact rate (95% CI 25.6-68.3 impacts/hr). Impact rates for tackling drills (those conducted without a blocker [95% CI 14.7-21.9 impacts/hr] and those with a blocker [95% CI 10.5-23.1 impacts/hr]) did not differ from game impact rates (95% CI 14.2-21.6 impacts/hr). Tackling drills were observed to have a greater proportion (between 40% and 50%) of impacts exceeding 60g than games (25%). The teams in this study participated in tackling or blocking drills for only 22% of their overall practice times, but these drills were responsible for 86% of all practice impacts exceeding 40g. CONCLUSIONS In youth football, high-magnitude impacts occur more often in practices than games, and some practice drills are associated with higher impact rates and accelerations than others. To mitigate high-magnitude head impact exposure in youth football, practices should be modified to decrease the time spent in drills with high impact rates, potentially eliminating a drill such as King of the Circle

Development and field performance of indy race car head impact padding.

Science.gov (United States)

Melvin, J W; Bock, H; Anderson, K; Gideon, T

2001-11-01

The close-fitting cockpit of the modern Indy car single seat race car has the potential to provide a high level of head and neck impact protection in rear and side impacts. Crash investigation has shown that a wide variety of materials have been used as the padding for these cockpits and, as a result, produced varying outcomes in crashes. Additionally, these pads have not always been positioned for optimal performance. The purpose of this study was to investigate the head impact performance of a variety of energy-absorbing padding materials under impact conditions typical of Indy car rear impacts and to identify superior materials and methods of improving their performance as race car head pads. An extensive series of tests with the helmeted Hybrid III test dummy head and neck on an impact mini-sled was conducted to explore head padding concepts. Following this, a performance specification for a simplified impact test using a rigid headform that simulates the helmeted head was developed and recommendations for performance levels of head padding based on biomechanical data on helmeted head impacts were made. In 1997, during the time that the head pad research was being performed, the Indy Racing League introduced a new chassis specification for their cars. There were a number of rear- and side-impact crashes during that season that resulted in seven severe head injuries. Examples of the head padding in those cars were included in the experimental study. The results of the head pad research were used to specify new padding materials that met the new biomechanical criteria. The placement of the head pads was also changed for better location of the padding. These changes instituted in 1998 have reduced the number of head injuries in crashes similar to or more severe than those of 1997 and have resulted in only occasional moderate head injuries (concussions) in the 1998 and 1999 seasons.

Effect of head rotation in whiplash-type rear impacts.

Science.gov (United States)

Kumar, Shrawan; Ferrari, Robert; Narayan, Yogesh

2005-01-01

Knowledge is increasing about the electromyographic and kinematic response of the neck muscles to rear impact, and also recent information is available on the effect of a rear impact offset to the left (posterolateral). The effect of head rotation, however, at the time of rear impact is not known. The purpose of this study was to examine the effects of head rotation to the left and right on the cervical muscle response to increasing low-velocity posterolateral impacts. Twenty healthy volunteers were subjected to rear impacts of 4.7, 8.3, 10.9 and 13.7 m/s2 acceleration, offset by 45 degrees to the subject's left, with head rotation to right and left. Bilateral electromyograms of the sternocleidomastoids, trapezii and splenii capitis were recorded. Triaxial accelerometers recorded the acceleration of the sled, torso at the shoulder level, and head of the participant. With the head rotated to the right, at an acceleration of 13.7 m/s2, the left sternocleidomastoid generated 59% and the right sternocleidomastoid 20% of their maximal voluntary contraction (MVC) electromyogram (EMG). Under these conditions, the remaining muscles (both splenii capitis and trapezius) generated 25% or less of their MVC. With the head rotated to the left, at an acceleration of 13.7 m/s2, the right sternocleidomastoid generated 65% and the left sternocleidomastoid only 11% of the MVC EMG. Under these conditions, again the remaining muscles had low EMG activity (27% or less) with the exception of the left trapezius which generated 47% of its MVC. Electromyographic variables were significantly affected by the levels of acceleration (pfactor in determining the muscle response to whiplash, but head rotation at the time of impact is also important in this regard. More specifically, when a rear impact is left posterolateral, it results in increased EMG generation mainly in the contralateral sternocleidomastoid, as expected, but head rotation at the same time in this type of impact reduces the EMG

The Role of Classroom Quality in Explaining Head Start Impacts

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Connors, Maia C.; Friedman-Krauss, Allison H.; Morris, Pamela A.; Page, Lindsay C.; Feller, Avi

2014-01-01

This study seeks to answer the following question: Are impacts on Head Start classroom quality associated with impacts of Head Start on children's learning and development? This study employs a variety of descriptive and quasi-experimental methods to explore the role of classroom quality as a mediator or mechanism of Head Start impacts. This…

Assessment of head injury of children due to golf ball impact.

Science.gov (United States)

Lee, Heow Pueh; Wang, Fang

2010-10-01

Head trauma injury due to impact by a flying golf ball is one of the most severe possible injury accidents on the golf course. Numerical simulations based on the finite element method are presented to investigate head injury in children due to impact by a flying golf ball. The stress and energy flow patterns in a head model during the golf ball impact are computed for various combinations of striking speed, falling angle of the golf ball before impact, and impact location. It is found that a child is more prone to head injury due to golf ball impact on the frontal and side/temporal areas. The simulated results are found to conform to the clinical reports on children's head injuries from flying golf balls.

Head Impact Exposure and Neurologic Function of Youth Football Players.

Science.gov (United States)

Munce, Thayne A; Dorman, Jason C; Thompson, Paul A; Valentine, Verle D; Bergeron, Michael F

2015-08-01

Football players are subjected to repetitive impacts that may lead to brain injury and neurologic dysfunction. Knowledge about head impact exposure (HIE) and consequent neurologic function among youth football players is limited. This study aimed to measure and characterize HIE of youth football players throughout one season and explore associations between HIE and changes in selected clinical measures of neurologic function. Twenty-two youth football players (11-13 yr) wore helmets outfitted with a head impact telemetry (HIT) system to quantify head impact frequency, magnitude, duration, and location. Impact data were collected for each practice (27) and game (9) in a single season. Selected clinical measures of balance, oculomotor performance, reaction time, and self-reported symptoms were assessed before and after the season. The median individual head impacts per practice, per game, and throughout the entire season were 9, 12, and 252, respectively. Approximately 50% of all head impacts (6183) had a linear acceleration between 10g and 20g, but nearly 2% were greater than 80g. Overall, the head impact frequency distributions in this study population were similar in magnitude and location as in high school and collegiate football, but total impact frequency was lower. Individual changes in neurologic function were not associated with cumulative HIE. This study provides a novel examination of HIE and associations with short-term neurologic function in youth football and notably contributes to the limited HIE data currently available for this population. Whereas youth football players can experience remarkably similar head impact forces as high school players, cumulative subconcussive HIE throughout one youth football season may not be detrimental to short-term clinical measures of neurologic function.

Head Impact Exposure in Junior and Adult Australian Football Players

Directory of Open Access Journals (Sweden)

Mark Hecimovich

2018-01-01

Full Text Available This study measured and compared the frequency, magnitude, and distribution of head impacts sustained by junior and adult Australian football players, respectively, and between player positions over a season of games. Twelve junior and twelve adult players were tracked using a skin-mounted impact sensor. Head impact exposure, including frequency, magnitude, and location of impacts, was quantified using previously established methods. Over the collection period, there were no significant differences in the impact frequency between junior and adult players. However, there was a significant increase in the frequency of head impacts for midfielders in both grades once we accounted for player position. A comparable amount of head impacts in both junior and adult players has implications for Australian football regarding player safety and medical coverage as younger players sustained similar impact levels as adult players. The other implication of a higher impact profile within midfielders is that, by targeting education and prevention strategies, a decrease in the incidence of sports-related concussion may result.

Head Start Impact Study. Final Report. Executive Summary

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Puma, Michael; Bell, Stephen; Cook, Ronna; Heid, Camilla; Shapiro, Gary; Broene, Pam; Jenkins, Frank; Fletcher, Philip; Quinn, Liz; Friedman, Janet; Ciarico, Janet; Rohacek, Monica; Adams, Gina; Spier, Elizabeth

2010-01-01

This report summarizes the findings from a study on the impacts of Head Start on children and families during the children's preschool, kindergarten, and 1st grade years. Its study goals were to: (1) Determine the impact of Head Start on children's school readiness, and on parental practices that support children's development; and to (2)…

Characterizing Verified Head Impacts in High School Girls' Lacrosse.

Science.gov (United States)

Caswell, Shane V; Lincoln, Andrew E; Stone, Hannah; Kelshaw, Patricia; Putukian, Margot; Hepburn, Lisa; Higgins, Michael; Cortes, Nelson

2017-12-01

Girls' high school lacrosse players have higher rates of head and facial injuries than boys. Research indicates that these injuries are caused by stick, player, and ball contacts. Yet, no studies have characterized head impacts in girls' high school lacrosse. To characterize girls' high school lacrosse game-related impacts by frequency, magnitude, mechanism, player position, and game situation. Descriptive epidemiology study. Thirty-five female participants (mean age, 16.2 ± 1.2 years; mean height, 1.66 ± 0.05 m; mean weight, 61.2 ± 6.4 kg) volunteered during 28 games in the 2014 and 2015 lacrosse seasons. Participants wore impact sensors affixed to the right mastoid process before each game. All game-related impacts recorded by the sensors were verified using game video. Data were summarized for all verified impacts in terms of frequency, peak linear acceleration (PLA), and peak rotational acceleration (PRA). Descriptive statistics and impact rates were calculated. Fifty-eight verified game-related impacts ≥20 g were recorded (median PLA, 33.8 g; median PRA, 6151.1 rad/s 2 ) during 467 player-games. The impact rate for all game-related verified impacts was 0.12 per athlete-exposure (AE) (95% CI, 0.09-0.16), equivalent to 2.1 impacts per team game, indicating that each athlete suffered fewer than 2 head impacts per season ≥20 g. Of these impacts, 28 (48.3%) were confirmed to directly strike the head, corresponding with an impact rate of 0.05 per AE (95% CI, 0.00-0.10). Overall, midfielders (n = 28, 48.3%) sustained the most impacts, followed by defenders (n = 12, 20.7%), attackers (n = 11, 19.0%), and goalies (n = 7, 12.1%). Goalies demonstrated the highest median PLA and PRA (38.8 g and 8535.0 rad/s 2 , respectively). The most common impact mechanisms were contact with a stick (n = 25, 43.1%) and a player (n = 17, 29.3%), followed by the ball (n = 7, 12.1%) and the ground (n = 7, 12.1%). One hundred percent of ball impacts occurred to goalies. Most impacts

Influence of impact speed on head and brain injury outcome in vulnerable road user impacts to the car hood.

Science.gov (United States)

Fredriksson, Rikard; Zhang, Liying; Boström, Ola; Yang, King

2007-10-01

EuroNCAP and regulations in Europe and Japan evaluate the pedestrian protection performance of cars. The test methods are similar and they all have requirements for the passive protection of the hood area at a pedestrian to car impact speed of 40 km/h. In Europe, a proposal for a second phase of the regulation mandates a brake-assist system along with passive requirements. The system assists the driver in optimizing the braking performance during panic braking, resulting in activation only when the driver brakes sufficiently. In a European study this was estimated to occur in about 50% of pedestrian accidents. A future system for brake assistance will likely include automatic braking, in response to a pre-crash sensor, to avoid or mitigate injuries of vulnerable road users. An important question is whether these systems will provide sufficient protection, or if a parallel, passive pedestrian protection system will be necessary. This study investigated the influence of impact speed on head and brain injury risk, in impacts to the carhood. One car model was chosen and a rigid adjustable plate was mounted under the hood. Free-flying headform impacts were carried out at 20 and 30 km/h head impact velocities at different under-hood distances, 20 to 100 mm; and were compared to earlier tests at 40 km/h. The EEVC WG17 adult pedestrian headform was used for non-rotating tests and a Hybrid III adult 50th percentile head was used for rotational tests where linear and rotational acceleration was measured. Data from the rotational tests was used as input to a validated finite element model of the human head, the Wayne State University Head Injury Model (WSUHIM). The model was utilized to assess brain injury risk and potential injury mechanism in a pedestrian-hood impact. Although this study showed that it was not necessarily true that a lower HIC value reduced the risk for brain injury, it appeared, for the tested car model, under-hood distances of 60 mm in 20 km/h and 80 mm

Head impact exposure measured in a single youth football team during practice drills.

Science.gov (United States)

Kelley, Mireille E; Kane, Joeline M; Espeland, Mark A; Miller, Logan E; Powers, Alexander K; Stitzel, Joel D; Urban, Jillian E

2017-11-01

OBJECTIVE This study evaluated the frequency, magnitude, and location of head impacts in practice drills within a youth football team to determine how head impact exposure varies among different types of drills. METHODS On-field head impact data were collected from athletes participating in a youth football team for a single season. Each athlete wore a helmet instrumented with a Head Impact Telemetry (HIT) System head acceleration measurement device during all preseason, regular season, and playoff practices. Video was recorded for all practices, and video analysis was performed to verify head impacts and assign each head impact to a specific drill. Eleven drills were identified: dummy/sled tackling, install, special teams, Oklahoma, one-on-one, open-field tackling, passing, position skill work, multiplayer tackle, scrimmage, and tackling drill stations. Generalized linear models were fitted to log-transformed data, and Wald tests were used to assess differences in head accelerations and impact rates. RESULTS A total of 2125 impacts were measured during 30 contact practices in 9 athletes (mean age 11.1 ± 0.6 years, mean mass 44.9 ± 4.1 kg). Open-field tackling had the highest median and 95th percentile linear accelerations (24.7 g and 97.8 g, respectively) and resulted in significantly higher mean head accelerations than several other drills. The multiplayer tackle drill resulted in the highest head impact frequency, with an average of 0.59 impacts per minute per athlete, but the lowest 95th percentile linear accelerations of all drills. The front of the head was the most common impact location for all drills except dummy/sled tackling. CONCLUSIONS Head impact exposure varies significantly in youth football practice drills, with several drills exposing athletes to high-magnitude and/or high-frequency head impacts. These data suggest that further study of practice drills is an important step in developing evidence-based recommendations for modifying or eliminating

How Well Does the Latest Anthropomorphic Test Device Mimic Human Impact Responses?

Science.gov (United States)

Newby, Nate; Somers, Jeff; Caldewll, Erin; Gernhardt, Michael

2014-01-01

One of the goals of the NASA Occupant Protection Group is to understand the human tolerance to dynamic loading. This knowledge has to come through indirect approaches such as existing human response databases, anthropometric test devices (ATD), animal testing, post-­-mortem human subjects, and models. This study investigated the biofidelity of the National Highway Traffic Safety Administration's ATD named the THOR (test device for human occupant restraint). If THOR responds comparably to humans, then it could potentially be used as a human surrogate to help validate space vehicle requirements for occupant protection. The THOR responses to frontal and spinal impacts (ranging from 8 to 12 G with rise times of 40, 70, and 100 ms) were measured and compared to human volunteer responses (95 trials in frontal and 58 in spinal) previously collected by the U. S. Air Force on the same horizontal impact accelerator. The impact acceleration profiles tested are within the expected range of multi-­-purpose crew vehicle (MPCV) landing dynamics. A correlation score was calculated for each THOR to human comparison using CORA (CORrelation and Analysis) software. A two-­-parameter beta distribution model fit was obtained for each dependent variable using maximum likelihood estimation. For frontal impacts, the THOR head x-­-acceleration peak response correlated with the human response at 8 and 10-­-G 100 ms but not 10-­-G 70 ms. The phase lagged the human response. Head z-­-acceleration was not correlated. Chest x-­-acceleration was in phase, had a higher peak response, and was well correlated with lighter subjects (Cora = 0.8 for 46 kg vs. Cora = 0.4 for 126 kg). Head x-­-displacement had a leading phase. Several subjects responded with the same peak displacement but the mean of the group was lower. The shoulder x-­-displacement was in phase but had higher peaks than the human response. For spinal impacts, the THOR head x-­-acceleration was not well correlated. Head and

Development of a human head FE model for the impact analysis using VOXEL approach and simulation for the assessment on the focal brain injury

International Nuclear Information System (INIS)

Watanabe, Dai; Yuge, Kohei; Nishimoto, Tetsuya; Murakami, Shigeyuki; Takao, Hiroyuki

2008-01-01

In this paper, a three-dimensional digital human-head model was developed and several dynamic analyses on the head trauma were conducted. This model was built up by the VOXEL approach using 433 slice CT images (512 x 512 pixels) and made of 1.22 million parallelepiped finite elements with 10 anatomical tissue properties such as scalp, cerebrospinal fluid (CSF), skull, brain, dura mater and so on. The numerical analyses were conducted using a finite element code the authors have developed. The main features of the code are it is based on the explicit time integration method and it uses the one point integration method to evaluate the equivalent nodal forces with the hourglass control proposed by Flanagan and Belythcko and it utilizes the parallel computation with the Massage Passing Interface (MPI). In order to verify the developed model, the head impact experiment for a cadaver by Nahum et al. was simulated. The calculated results showed good agreement with experimental ones. A front and rear impact analyses were also performed investigate the relation between the impact direction and the positions of the high measurement of pressure and stresses in brain. The obtained results represent that brain injury has a closer relation with the Mises equivalent stress rather than the pressure. At this time, the large deformation of a frontal cranial base was observed in both frontal and occipital impact analyses. We expect that it induces the brain injury in a frontal lobe regardless of the impact positions. (author)

Analysis of impact noise induced by hitting of titanium head golf driver.

Science.gov (United States)

Kim, Young Ho; Kim, Young Chul; Lee, Jun Hee; An, Yong-Hwi; Park, Kyung Tae; Kang, Kyung Min; Kang, Yeon June

2014-11-01

The hitting of titanium head golf driver against golf ball creates a short duration, high frequency impact noise. We analyzed the spectra of these impact noises and evaluated the auditory hazards from exposure to the noises. Noises made by 10 titanium head golf drivers with five maximum hits were collected, and the spectra of the pure impact sounds were studied using a noise analysis program. The noise was measured at 1.7 m (position A) and 3.4 m (position B) from the hitting point in front of the hitter and at 3.4 m (position C) behind the hitting point. Average time duration was measured and auditory risk units (ARUs) at position A were calculated using the Auditory Hazard Assessment Algorithm for Humans. The average peak levels at position A were 119.9 dBA at the sound pressure level (SPL) peak and 100.0 dBA at the overall octave level. The average peak levels (SPL and overall octave level) at position B were 111.6 and 96.5 dBA, respectively, and at position C were 111.5 and 96.7 dBA, respectively. The average time duration and ARUs measured at position A were 120.6 ms and 194.9 units, respectively. Although impact noises made by titanium head golf drivers showed relatively low ARUs, individuals enjoying golf frequently may be susceptible to hearing loss due to the repeated exposure of this intense impact noise with short duration and high frequency. Unprotected exposure to impact noises should be limited to prevent cochleovestibular disorders.

Video Analysis Verification of Head Impact Events Measured by Wearable Sensors.

Science.gov (United States)

Cortes, Nelson; Lincoln, Andrew E; Myer, Gregory D; Hepburn, Lisa; Higgins, Michael; Putukian, Margot; Caswell, Shane V

2017-08-01

Wearable sensors are increasingly used to quantify the frequency and magnitude of head impact events in multiple sports. There is a paucity of evidence that verifies head impact events recorded by wearable sensors. To utilize video analysis to verify head impact events recorded by wearable sensors and describe the respective frequency and magnitude. Cohort study (diagnosis); Level of evidence, 2. Thirty male (mean age, 16.6 ± 1.2 years; mean height, 1.77 ± 0.06 m; mean weight, 73.4 ± 12.2 kg) and 35 female (mean age, 16.2 ± 1.3 years; mean height, 1.66 ± 0.05 m; mean weight, 61.2 ± 6.4 kg) players volunteered to participate in this study during the 2014 and 2015 lacrosse seasons. Participants were instrumented with GForceTracker (GFT; boys) and X-Patch sensors (girls). Simultaneous game video was recorded by a trained videographer using a single camera located at the highest midfield location. One-third of the field was framed and panned to follow the ball during games. Videographic and accelerometer data were time synchronized. Head impact counts were compared with video recordings and were deemed valid if (1) the linear acceleration was ≥20 g, (2) the player was identified on the field, (3) the player was in camera view, and (4) the head impact mechanism could be clearly identified. Descriptive statistics of peak linear acceleration (PLA) and peak rotational velocity (PRV) for all verified head impacts ≥20 g were calculated. For the boys, a total recorded 1063 impacts (2014: n = 545; 2015: n = 518) were logged by the GFT between game start and end times (mean PLA, 46 ± 31 g; mean PRV, 1093 ± 661 deg/s) during 368 player-games. Of these impacts, 690 were verified via video analysis (65%; mean PLA, 48 ± 34 g; mean PRV, 1242 ± 617 deg/s). The X-Patch sensors, worn by the girls, recorded a total 180 impacts during the course of the games, and 58 (2014: n = 33; 2015: n = 25) were verified via video analysis (32%; mean PLA, 39 ± 21 g; mean PRV, 1664 �

Player and Game Characteristics and Head Impacts in Female Youth Ice Hockey Players.

Science.gov (United States)

Reed, Nick; Taha, Tim; Greenwald, Richard; Keightley, Michelle

2017-08-01

  Despite the growing popularity of ice hockey among female youth and interest in the biomechanics of head impacts in sport, the head impacts sustained by this population have yet to be characterized.   To describe the number of, biomechanical characteristics of, and exposure to head impacts of female youth ice hockey players during competition and to investigate the influences of player and game characteristics on head impacts.   Cohort study.   Twenty-seven female youth ice hockey players (mean age = 12.5 ± 0.52 years) wore instrumented ice hockey helmets during 66 ice hockey games over a 3-year period. Data specific to player, game, and biomechanical head impact characteristics were recorded. A multiple regression analysis identified factors most associated with head impacts of greater frequency and severity.   A total of 436 total head impacts were sustained during 6924 minutes of active ice hockey participation (0.9 ± 0.6 impacts per player per game; range, 0-2.1). A higher body mass index (BMI) significantly predicted a higher number of head impacts sustained per game (P = .008). Linear acceleration of head impacts was greater in older players and those who played the forward position, had a greater BMI, and spent more time on the ice (P = .008), whereas greater rotational acceleration was present in older players who had a greater BMI and played the forward position (P = .008). During tournament games, increased ice time predicted increased severity of head impacts (P = .03).   This study reveals for the first time that head impacts are occurring in female youth ice hockey players, albeit at a lower rate and severity than in male youth ice hockey players, despite the lack of intentional body checking.

Systematic biases in human heading estimation.

Directory of Open Access Journals (Sweden)

Luigi F Cuturi

Full Text Available Heading estimation is vital to everyday navigation and locomotion. Despite extensive behavioral and physiological research on both visual and vestibular heading estimation over more than two decades, the accuracy of heading estimation has not yet been systematically evaluated. Therefore human visual and vestibular heading estimation was assessed in the horizontal plane using a motion platform and stereo visual display. Heading angle was overestimated during forward movements and underestimated during backward movements in response to both visual and vestibular stimuli, indicating an overall multimodal bias toward lateral directions. Lateral biases are consistent with the overrepresentation of lateral preferred directions observed in neural populations that carry visual and vestibular heading information, including MSTd and otolith afferent populations. Due to this overrepresentation, population vector decoding yields patterns of bias remarkably similar to those observed behaviorally. Lateral biases are inconsistent with standard bayesian accounts which predict that estimates should be biased toward the most common straight forward heading direction. Nevertheless, lateral biases may be functionally relevant. They effectively constitute a perceptual scale expansion around straight ahead which could allow for more precise estimation and provide a high gain feedback signal to facilitate maintenance of straight-forward heading during everyday navigation and locomotion.

Environmental and Physiological Factors Affect Football Head Impact Biomechanics.

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Mihalik, Jason P; Sumrall, Adam Z; Yeargin, Susan W; Guskiewicz, Kevin M; King, Kevin B; Trulock, Scott C; Shields, Edgar W

2017-10-01

Recent anecdotal trends suggest a disproportionate number of head injuries in collegiate football players occur during preseason football camp. In warmer climates, this season also represents the highest risk for heat-related illness among collegiate football players. Because concussion and heat illnesses share many common symptoms, we need 1) to understand if environmental conditions, body temperature, and hydration status affect head impact biomechanics; and 2) to determine if an in-helmet thermistor could provide a valid measure of gastrointestinal temperature. A prospective cohort of 18 Division I college football players (age, 21.1 ± 1.4 yr; height, 187.7 ± 6.6 cm; mass, 114.5 ± 23.4 kg). Data were collected during one control and three experimental sessions. During each session, the Head Impact Telemetry System recorded head impact biomechanics (linear acceleration, rotational acceleration, and severity profile) and in-helmet temperature. A wet bulb globe device recorded environmental conditions, and CorTemp™ Ingestible Core Body Temperature Sensors recorded gastrointestinal temperature. Our findings suggest that linear acceleration (P = 0.57), rotational acceleration (P = 0.16), and Head Impact Technology severity profile (P = 0.33) are not influenced by environmental or physiological conditions. We did not find any single or combination of predictors for impact severity. Rotational acceleration was approaching significance between our early experimental sessions when compared with our control session. More research should be conducted to better understand if rotational accelerations are a component of impact magnitudes that are affected due to changes in environmental conditions, body temperature, and hydration status.

Football Players' Head-Impact Exposure After Limiting of Full-Contact Practices.

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Broglio, Steven P; Williams, Richelle M; O'Connor, Kathryn L; Goldstick, Jason

2016-07-01

Sporting organizations limit full-contact football practices to reduce concussion risk and based on speculation that repeated head impacts may result in long-term neurodegeneration. To directly compare head-impact exposure in high school football players before and after a statewide restriction on full-contact practices. Cross-sectional study. High school football field. Participants were varsity football athletes from a single high school. Before the rule change, 26 athletes (age = 16.2 ± 0.8 years, height = 179.6 ± 6.4 cm, weight = 81.9 ± 13.1 kg) participated. After the rule change, 24 athletes (age = 15.9 ± 0.8 years, height = 178.3 ± 6.5 cm, weight = 76.2 ± 11.6 kg) participated. Nine athletes participated in both years of the investigation. Head-impact exposure was monitored using the Head Impact Telemetry System while the athletes participated in football games and practices in the seasons before and after the rule change. Head-impact frequency, location, and magnitude (ie, linear acceleration, rotational acceleration, and Head Impact Telemetry severity profile [HITsp], respectively) were measured. A total of 15 398 impacts (592 impacts per player per season) were captured before the rule change and 8269 impacts (345 impacts per player per season) after the change. An average 42% decline in impact exposure occurred across all players, with practice-exposure declines occurring among linemen (46% decline); receivers, cornerbacks, and safeties (41% decline); and tight ends, running backs (including fullbacks), and linebackers (39% decline). Impact magnitudes remained largely unchanged between the years. A rule change limiting full-contact high school football practices appears to have been effective in reducing head-impact exposure across all players, with the largest reduction occurring among linemen. This finding is likely associated with the rule modification, particularly because the coaching staff and offensive scheme remained consistent, yet how

Field Distribution of Transcranial Static Magnetic Stimulation in Realistic Human Head Model.

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Tharayil, Joseph J; Goetz, Stefan M; Bernabei, John M; Peterchev, Angel V

2017-10-10

The objective of this work was to characterize the magnetic field (B-field) that arises in a human brain model from the application of transcranial static magnetic field stimulation (tSMS). The spatial distribution of the B-field magnitude and gradient of a cylindrical, 5.08 cm × 2.54 cm NdFeB magnet were simulated in air and in a human head model using the finite element method and calibrated with measurements in air. The B-field was simulated for magnet placements over prefrontal, motor, sensory, and visual cortex targets. The impact of magnetic susceptibility of head tissues on the B-field was quantified. Peak B-field magnitude and gradient respectively ranged from 179-245 mT and from 13.3-19.0 T/m across the cortical targets. B-field magnitude, focality, and gradient decreased with magnet-cortex distance. The variation in B-field strength and gradient across the anatomical targets largely arose from the magnet-cortex distance. Head magnetic susceptibilities had negligible impact on the B-field characteristics. The half-maximum focality of the tSMS B-field ranged from 7-12 cm 3 . This is the first presentation and characterization of the three-dimensional (3D) spatial distribution of the B-field generated in a human brain model by tSMS. These data can provide quantitative dosing guidance for tSMS applications across various cortical targets and subjects. The finding that the B-field gradient is high near the magnet edges should be considered in studies where neural tissue is placed close to the magnet. The observation that susceptibility has negligible effects confirms assumptions in the literature. © 2017 International Neuromodulation Society.

Comprehensive Coach Education Reduces Head Impact Exposure in American Youth Football

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Kerr, Zachary Y.; Yeargin, Susan W.; Valovich McLeod, Tamara C.; Mensch, James; Hayden, Ross; Dompier, Thomas P.

2015-01-01

Background: Despite little evidence that defines a threshold of head impact exposure or that participation in youth sports leads to long-term cognitive impairments, it is prudent to identify methods of reducing the frequency of head impacts. Purpose: To compare the mean number of head impacts between youth football players in practice and games between leagues that implemented the Heads Up Football (HUF) educational program and those that did not (NHUF). Study Design: Cohort study; Level of evidence, 2. Methods: During the 2014 season, head impact exposure was measured using xPatch accelerometers from 70 youth football players aged 8 to 15 years from 5 leagues. Data were collected during both games and practices. The NHUF group comprised 32 players from 8 teams within 3 leagues. The HUF group comprised 38 players from 7 teams within 2 leagues. Independent-sample t tests evaluated differences in head impact exposure across groups (ie, HUF and NHUF). Results: Players (mean ± SD: age, 11.7 ± 1.4 years; height, 152.2 ± 10.5 cm; weight, 51.6 ± 9.6 kg) experienced a total of 7478 impacts over 10g, of which 4250 (56.8%) and 3228 (43.2%) occurred in practices and games, respectively. The majority of impacts occurred within the NHUF group (62.0%), followed by the HUF group (38.0%). With a 10g impact threshold, the mean number of impacts during practice per individual event was lower in the HUF group (mean ± SD, 5.6 ± 2.9) than in the NHUF group (mean ± SD, 8.9 ± 3.1; difference, 3.4; 95% CI, 2.9-3.9). This difference was attenuated when the threshold was changed to 20g but remained significant (difference, 1.0; 95% CI, 0.7-1.3). At both the 10g and 20g impact thresholds, no differences were found in games. Conclusion: Players who participated in HUF leagues accumulated fewer head impacts per practice at both the 10g and 20g thresholds. Youth football leagues should consider the HUF educational program, while exploring additional interventions, to help reduce the

A dictionary learning approach for human sperm heads classification.

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Shaker, Fariba; Monadjemi, S Amirhassan; Alirezaie, Javad; Naghsh-Nilchi, Ahmad Reza

2017-12-01

To diagnose infertility in men, semen analysis is conducted in which sperm morphology is one of the factors that are evaluated. Since manual assessment of sperm morphology is time-consuming and subjective, automatic classification methods are being developed. Automatic classification of sperm heads is a complicated task due to the intra-class differences and inter-class similarities of class objects. In this research, a Dictionary Learning (DL) technique is utilized to construct a dictionary of sperm head shapes. This dictionary is used to classify the sperm heads into four different classes. Square patches are extracted from the sperm head images. Columnized patches from each class of sperm are used to learn class-specific dictionaries. The patches from a test image are reconstructed using each class-specific dictionary and the overall reconstruction error for each class is used to select the best matching class. Average accuracy, precision, recall, and F-score are used to evaluate the classification method. The method is evaluated using two publicly available datasets of human sperm head shapes. The proposed DL based method achieved an average accuracy of 92.2% on the HuSHeM dataset, and an average recall of 62% on the SCIAN-MorphoSpermGS dataset. The results show a significant improvement compared to a previously published shape-feature-based method. We have achieved high-performance results. In addition, our proposed approach offers a more balanced classifier in which all four classes are recognized with high precision and recall. In this paper, we use a Dictionary Learning approach in classifying human sperm heads. It is shown that the Dictionary Learning method is far more effective in classifying human sperm heads than classifiers using shape-based features. Also, a dataset of human sperm head shapes is introduced to facilitate future research. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparative analyses of bicyclists and motorcyclists in vehicle collisions focusing on head impact responses.

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Wang, Xinghua; Peng, Yong; Yi, Shengen

2017-11-01

To investigate the differences of the head impact responses between bicyclists and motorcyclists in vehicle collisions. A series of vehicle-bicycle and vehicle-motorcycle lateral impact simulations on four vehicle types at seven vehicle speeds (30, 35, 40, 45, 50, 55 and 60 km/h) and three two-wheeler moving speeds (5, 7.5 and 10 km/h for bicycle, 10, 12.5 and 15 km/h for motorcycle) were established based on PC-Crash software. To further comprehensively explore the differences, additional impact scenes with other initial conditions, such as impact angle (0, π/3, 2π/3 and π) and impact position (left, middle and right part of vehicle front-end), also were supplemented. And then, extensive comparisons were accomplished with regard to average head peak linear acceleration, average head impact speed, average head peak angular acceleration, average head peak angular speed and head injury severity. The results showed there were prominent differences of kinematics and body postures for bicyclists and motorcyclists even under same impact conditions. The variations of bicyclist head impact responses with the changing of impact conditions were a far cry from that of motorcyclists. The average head peak linear acceleration, average head impact speed and average head peak angular acceleration values were higher for motorcyclists than for bicyclists in most cases, while the bicyclists received greater average head peak angular speed values. And the head injuries of motorcyclists worsened faster with increased vehicle speed. The results may provide even deeper understanding of two-wheeler safety and contribute to improve the public health affected by road traffic accidents.

Effect of cell-phone radiofrequency on angiogenesis and cell invasion in human head and neck cancer cells.

Science.gov (United States)

Alahmad, Yaman M; Aljaber, Mohammed; Saleh, Alaaeldin I; Yalcin, Huseyin C; Aboulkassim, Tahar; Yasmeen, Amber; Batist, Gerald; Moustafa, Ala-Eddin Al

2018-05-13

Today, the cell phone is the most widespread technology globally. However, the outcome of cell-phone radiofrequency on head and neck cancer progression has not yet been explored. The chorioallantoic membrane (CAM) and human head and neck cancer cell lines, FaDu and SCC25, were used to explore the outcome of cell-phone radiofrequency on angiogenesis, cell invasion, and colony formation of head and neck cancer cells, respectively. Western blot analysis was used to investigate the impact of the cell phone on the regulation of E-cadherin and Erk1/Erk2 genes. Our data revealed that cell-phone radiofrequency promotes angiogenesis of the CAM. In addition, the cell phone enhances cell invasion and colony formation of human head and neck cancer cells; this is accompanied by a downregulation of E-cadherin expression. More significantly, we found that the cell phone can activate Erk1/Erk2 in our experimental models. Our investigation reveals that cell-phone radiofrequency could enhance head and neck cancer by stimulating angiogenesis and cell invasion via Erk1/Erk2 activation. © 2018 Wiley Periodicals, Inc.

Anne-Sylvie Catherin, Head of the Human Resources Department

CERN Multimedia

2009-01-01

Anne-Sylvie Catherin has been appointed Head of the Human Resources Department with effect from 1 August 2009. Mrs Catherin is a lawyer specialized in International Administration and joined CERN in 1996 as legal advisor within the Office of the HR Department Head. After having been promoted to the position of Group Leader responsible for social and statutory conditions in 2000, Mrs Catherin was appointed Deputy of the Head of the Human Resources Department and Group Leader responsible for Strategy, Management and Development from 2005 to date. Since 2005, she has also served as a member of CCP and TREF. In the execution of her mandate as Deputy HR Department Head, Mrs Catherin closely assisted the HR Department Head in the organization of the Department and in devising new HR policies and strategies. She played an instrumental role in the last five-yearly review and in the revision of the Staff Rules and Regulations.

An experimental and numerical investigation of head dynamics due to stick impacts in girls' lacrosse.

Science.gov (United States)

Morse, Justin D; Franck, Jennifer A; Wilcox, Bethany J; Crisco, Joseph J; Franck, Christian

2014-12-01

A method of investigating head acceleration and intracranial dynamics from stick impacts in girls' and women's lacrosse was developed using headform impact experiments and a finite element head model. Assessing the likelihood of head injury due to stick-head impacts is of interest in girls' and women's lacrosse due to the current lack of head protection during play. Experimental and simulation data were compared to characterize the head acceleration caused by stick-head impacts. Validation against cadaver head impact experiments ensures that the finite element model, with its relatively simple material properties, can provide means to develop a better understanding of the intracranial dynamics during lacrosse stick impacts. Our numerical results showed the peak acceleration at the center of gravity increased linearly with impact force, and was generally in agreement with the experimental data. von Mises stresses and peak principal strains, two common literature injury indicators, were examined within the finite element model, and peak values were below the previously reported thresholds for mild traumatic brain injury. By reconstructing typical in-game, unprotected stick-head impacts, this investigation lays the foundation for a quantitative methodology of injury prediction in girls' and womens' lacrosse.

Head Start's Impact Is Contingent on Alternative Type of Care in Comparison Group

Science.gov (United States)

Zhai, Fuhua; Brooks-Gunn, Jeanne; Waldfogel, Jane

2014-01-01

Using data ("n" = 3,790 with 2,119 in the 3-year-old cohort and 1,671 in the 4-year-old cohort) from 353 Head Start centers in the Head Start Impact Study, the only large-scale randomized experiment in Head Start history, this article examined the impact of Head Start on children's cognitive and parent-reported social-behavioral outcomes…

Elemental Water Impact Test: Phase 2 36-Inch Aluminum Tank Head

Science.gov (United States)

Vassilakos, Gregory J.

2014-01-01

Spacecraft are being designed based on LS-DYNA simulations of water landing impacts. The Elemental Water Impact Test (EWIT) series was undertaken to assess the accuracy of LS-DYNA water impact simulations. EWIT Phase 2 featured a 36-inch aluminum tank head. The tank head was outfitted with one accelerometer, twelve pressure transducers, three string potentiometers, and four strain gages. The tank head was dropped from heights of 1 foot and 2 feet. The focus of this report is the correlation of analytical models against test data. As a measure of prediction accuracy, peak responses from the baseline LS-DYNA model were compared to peak responses from the tests.

Head Start Impact on Social-Emotional Outcomes for Children with Disabilities

Science.gov (United States)

Lee, Kyunghee; Calkins, Andrea; Shin, Tae Seob

2016-01-01

Objective: Using the Head Start Impact Study data, this study examines Head Start's impacts on social-emotional outcomes for children with disabilities. Method: Among 4,442 children, 570 children were reported to have disabilities. Ordinary least squares regression was used to determine whether the number of disabilities, having an individualized…

Head impacts in a junior rugby league team measured with a wireless head impact sensor: an exploratory analysis.

Science.gov (United States)

King, Doug; Hume, Patria; Gissane, Conor; Clark, Trevor

2017-01-01

OBJECTIVE The aim of this study was to investigate the frequency, magnitude, and distribution of head impacts sustained by players in a junior rugby league over a season of matches. METHODS The authors performed a prospective cohort analysis of impact magnitude, frequency, and distribution on data collected with instrumented XPatches worn behind the ear of players in an "under-11" junior rugby league team (players under 11 years old). RESULTS A total of 1977 impacts were recorded. Over the course of the study, players sustained an average of 116 impacts (average of 13 impacts per player per match). The measured linear acceleration ranged from 10g to 123g (mean 22g, median 16g, and 95th percentile 57g). The rotational acceleration ranged from 89 rad/sec 2 to 22,928 rad/sec 2 (mean 4041 rad/sec 2 , median 2773 rad/sec 2 , and 95th percentile 11,384 rad/sec 2 ). CONCLUSIONS The level of impact severity based on the magnitude of impacts for linear and rotational accelerations recorded was similar to the impacts reported in studies of American junior and high school football, collegiate football, and youth ice hockey players, but the players in the rugby league cohort were younger, had less body mass, and played at a slower speed than the American players. Junior rugby league players are required to tackle the player to the ground and use a different tackle technique than that used in American football, likely increasing the rotational accelerations recorded at the head.

Analysis of head impacts during sub-elite hurling practice sessions.

Science.gov (United States)

O'Sullivan, D; Roe, M; Blake, C

2018-06-01

The reported incidence of head and neck injuries in hurling is 0.12 per 1000 hours, but no previous research has quantified head impact characteristics in this sport. Here, a wireless accelerometer and gyroscope captured head impacts, in 20 senior club level hurling players. Peak linear and rotational acceleration and impact location were recorded during three hurling training sessions, each player participating once. A mean of 27.9 impacts (linear acceleration >10g) per player, per session were recorded; 1314 impacts during a total exposure time of 247 minutes. Only 2.6% impacts had peak linear acceleration of >70g and 6.2% had peak rotational acceleration >7900 rad/s 2 . There were significant differences in the number and magnitude of impacts, quantified by the accelerometer, between three training sessions of differing intensity (ŋ2 0.03-0.09, p impacts during hurling, demonstrating the feasibility of this technology in the field. The sensors were able to discriminate between sessions of varying intensity. These data can be used to develop athlete monitoring protocols and may be useful in developing innovative helmet-testing standards for hurling. The potential for this technology to provide feedback has clinical utility for team medical personnel.

Clinical and scientific impact of human papillomavirus on head and neck cancer.

Science.gov (United States)

Friedman, Jeffrey M; Stavas, Mark J; Cmelak, Anthony J

2014-10-10

Head and neck cancer (HNC) arises from the skull base to the clavicles and is the fifth most common cancer in the world by incidence. Historically, in the developed world HNC was associated with tobacco use and alcohol consumption, and the combination of the two produced a synergistic increase in risk. However, beginning in 1983, investigators have found a significant and growing proportion of HNC patients with human papillomavirus-positive (HPV) tumors who neither drank nor used tobacco. Since that time, there has been increased interest in the molecular biology of HPV-positive HNC. Multiple studies now show that HPV has shifted the epidemiological landscape and prognosis of head and neck squamous cell carcinoma (HNSCC). These studies provide strong evidence for improved survival outcomes in patients with HPV-positive HNSCC compared to those with HPV-negative HNSCC. In many reports, HPV status is the strongest predictor of locoregional control, disease specific survival and overall survival. In response to these findings, there has been significant interest in the best management of HPV-positive disease. Discussions within major cooperative groups consider new trials designed to maintain the current strong survival outcomes while reducing the long-term treatment-related toxicities. This review will highlight the epidemiological, clinical and molecular discoveries surrounding HPV-related HNSCC over the recent decades and we conclude by suggesting how these findings may guide future treatment approaches.

Correlating cumulative sub-concussive head impacts in football with player performance - biomed 2009.

Science.gov (United States)

Rowson, Steven; Goforth, Mike W; Dietter, Dave; Brolinson, P Gunnar; Duma, Stefanan M

2009-01-01

The objective of this study was to investigate the effect of cumulative sub-concussive head impacts on football player performance. The helmets of three Virginia Tech football players were instrumented with a six accelerometer sensor capable of measuring head acceleration. Helmets were instrumented for every game during the 2006 and 2007 football seasons. Each time the head was impacted during a game, the sensor recorded the impact and wirelessly transmitted the data to a sideline computer. Furthermore, the coaching staff at Virginia Tech reviewed post-game film and evaluated each player's performance based on strict criteria. Players were awarded positive points for good plays and negative points for bad plays. Their performance scores were then normalized to a per play basis. Correlations of player performance with cumulative peak linear acceleration and cumulative head injury criterion (HIC) were evaluated. No consistent head acceleration-based measure showed a strong correlation with significance. In addition, relationship trends varied on a position basis. There are many factors other than head impacts that can affect a player's performance and more research is needed to further quantify such effects.

Brain response to primary blast wave using validated finite element models of human head and advanced combat helmet

Directory of Open Access Journals (Sweden)

Liying eZhang

2013-08-01

Full Text Available Blast-induced traumatic brain injury has emerged as a signature injury in combat casualty care. Present combat helmets are designed primarily to protect against ballistic and blunt impacts, but the current issue with helmets is protection concerning blasts. In order to delineate the blast wave attenuating capability of the Advanced Combat Helmet (ACH, a finite element (FE study was undertaken to evaluate the head response against blast loadings with and without helmet using a partially validated FE model of the human head and ACH. Four levels of overpressures (0.27-0.66 MPa from the Bowen’s lung iso-damage threshold curves were used to simulate blast insults. Effectiveness of the helmet with respect to head orientation was also investigated. The resulting biomechanical responses of the brain to blast threats were compared for human head with and without the helmet. For all Bowen’s cases, the peak intracranial pressures (ICP in the head ranged from 0.68-1.8 MPa in the coup cortical region. ACH was found to mitigate ICP in the head by 10-35%. Helmeted head resulted in 30% lower average peak brain strains and product of strain and strain rate. Among three blast loading directions with ACH, highest reduction in peak ICP (44% was due to backward blasts whereas the lowest reduction in peak ICP and brain strains was due to forward blast (27%. The biomechanical responses of a human head to primary blast insult exhibited directional sensitivity owing to the different geometry contours and coverage of the helmet construction and asymmetric anatomy of the head. Thus, direction-specific tolerances are needed in helmet design in order to offer omni-directional protection for the human head. The blasts of varying peak overpressures and durations that are believed to produce the same level of lung injury produce different levels of mechanical responses in the brain, and hence "iso-damage" curves for brain injury are likely different than the Bowen curves

Motion of the head and neck of female and male volunteers in rear impact car-to-car impacts.

Science.gov (United States)

Carlsson, Anna; Siegmund, Gunter P; Linder, Astrid; Svensson, Mats Y

2012-01-01

The objectives of this study were to quantify and compare dynamic motion responses between 50th percentile female and male volunteers in rear impact tests. These data are fundamental for developing future occupant models for crash safety development and assessment. High-speed video data from a rear impact test series with 21 male and 21 female volunteers at 4 and 8 km/h, originally presented in Siegmund et al. (1997), were used for further analysis. Data from a subset of female volunteers, 12 at 4 km/h and 9 at 8 km/h, were extracted from the original data set to represent the 50th percentile female. Their average height was 163 cm and their average weight was 62 kg. Among the male volunteers, 11 were selected, with an average height of 175 cm and an average weight of 73 kg, to represent the 50th percentile male. Response corridors were generated for the horizontal and angular displacements of the head, T1 (first thoracic vertebra), and the head relative to T1. T-tests were performed with the statistical significance level of .05 to quantify the significance of the differences in parameter values for the males and females. Several differences were found in the average motion response of the male and female volunteers at 4 and 8 km/h. Generally, females had smaller rearward horizontal and angular motions of the head and T1 compared to the males. This was mainly due to shorter initial head-to-head restraint distance and earlier head-to-head restraint contact for the females. At 8 km/h, the female volunteers showed 12 percent lower horizontal peak rearward head displacement (P = .018); 22 percent lower horizontal peak rearward head relative to T1 displacement (P = .018); and 30 percent lower peak head extension angle (P = .001). The females also had more pronounced rebound motion. This study indicates that there may be characteristic differences in the head-neck motion response between 50th percentile males and females in rear impacts. The exclusive use of 50th

Fall Protection Characteristics of Safety Belts and Human Impact Tolerance.

Science.gov (United States)

Hino, Yasumichi; Ohdo, Katsutoshi; Takahashi, Hiroki

2014-08-23

Many fatal accidents due to falls from heights have occurred at construction sites not only in Japan but also in other countries. This study aims to determine the fall prevention performance of two types of safety belts: a body belt 1) , which has been used for more than 40 yr in the Japanese construction industry as a general type of safety equipment for fall accident prevention, and a full harness 2, 3) , which has been used in many other countries. To determine human tolerance for impact trauma, this study discusses features of safety belts with reference 4-9) to relevant studies in the medical science, automobile crash safety, and aircrew safety. For this purpose, simple drop tests were carried out in a virtual workplace to measure impact load, head acceleration, and posture in the experiments, the Hybrid-III pedestrian model 10) was used as a human dummy. Hybrid-III is typically employed in official automobile crash tests (New Car Assessment Program: NCAP) and is currently recognized as a model that faithfully reproduces dynamic responses. Experimental results shows that safety performance strongly depends on both the variety of safety belts used and the shock absorbers attached onto lanyards. These findings indicate that fall prevention equipment, such as safety belts, lanyards, and shock absorbers, must be improved to reduce impact injuries to the human head and body during falls.

Clinical Risk Factors for Head Impact During Falls in Older Adults: A Prospective Cohort Study in Long-Term Care.

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Yang, Yijian; Mackey, Dawn C; Liu-Ambrose, Teresa; Leung, Pet-Ming; Feldman, Fabio; Robinovitch, Stephen N

To examine risk factors associated with head impact during falls in older adults in long-term care (LTC). Two LTC facilities in British Columbia, Canada. 160 LTC residents. Prospective cohort study. Between 2007 and 2014, we video captured 520 falls experienced by participants. Each fall video was analyzed to determine whether impact occurred to the head. Using generalized estimating equation models, we examined how head impact was associated with other fall characteristics and health status prior to the fall. Head impact occurred in 33% of falls. Individuals with mild cognitive impairment were at higher risk for head impact (odds ratio = 2.8; 95% confidence interval, 1.5-5.0) than those with more severe cognitive impairment. Impaired vision was associated with 2.0-fold (1.3-3.0) higher odds of head impact. Women were 2.2 times (1.4-3.3) more likely than men to impact their head during a fall. Head impact is common during falls in LTC, with less cognitively impaired, female residents who suffered from visual impairment, being most likely to impact their head. Future research should focus on improving our ability to detect neural consequences of head impact and evaluating the effect of interventions for reducing the risk for fall-related head injuries in LTC.

School Readiness in Children Living in Non-Parental Care: Impacts of Head Start

Science.gov (United States)

Lipscomb, Shannon T.; Pratt, Megan E.; Schmitt, Sara A.; Pears, Katherine C.; Kim, Hyoun K.

2013-01-01

The current study examines the effects of Head Start on the development of school readiness outcomes for children living in non-parental care. Data were obtained from the Head Start Impact Study, a randomized controlled trial of Head Start conducted with a nationally representative sample of Head Start programs and families. The sample included…

The Impact of Head Start on Children, Families and Communities. Final Report of the Head Start Evaluation, Synthesis and Utilization Project.

Science.gov (United States)

McKey, Ruth Hubbell; And Others

Including all Head Start research (both published and unpublished) and using, when possible, the statistical technique of meta-analysis, this final report of the Head Start Evaluation, Synthesis, and Utilization Project presents findings on the impact of Head Start on children's cognitive and socioemotional development, on child health and health…

Analysis of right anterolateral impacts: the effect of head rotation on the cervical muscle whiplash response

Directory of Open Access Journals (Sweden)

Narayan Yogesh

2005-05-01

Full Text Available Abstract Background The cervical muscles are considered a potential site of whiplash injury, and there are many impact scenarios for whiplash injury. There is a need to understand the cervical muscle response under non-conventional whiplash impact scenarios, including variable head position and impact direction. Methods Twenty healthy volunteers underwent right anterolateral impacts of 4.0, 7.6, 10.7, and 13.0 m/s2 peak acceleration, each with the head rotated to the left, then the head rotated to the right in a random order of impact severities. Bilateral electromyograms of the sternocleidomastoids, trapezii, and splenii capitis following impact were measured. Results At a peak acceleration of 13.0 m/s2, with the head rotated to the right, the right trapezius generated 61% of its maximal voluntary contraction electromyogram (MVC EMG, while all other muscles generated 31% or less of this variable (31% for the left trapezius, 13% for the right spleinus. capitis, and 16% for the left splenius capitis. The sternocleidomastoids muscles also tended to show an asymmetric EMG response, with the left sternocleidomastoid (the one responsible for head rotation to the right generating a higher percentage (26% of its MVC EMG than the left sternocleidomastoid (4% (p Conclusion The EMG response to a right anterolateral impact is highly dependent on the head position. The sternocleidomastoid responsible for the direction of head rotation and the trapezius ipsilateral to the direction of head rotation generate the most EMG activity.

Prediction and analysis of human thoracic impact responses and injuries in cadaver impacts using a full human body finite element model.

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Ruan, Jesse; El-Jawahri, Raed; Chai, Li; Barbat, Saeed; Prasad, Priya

2003-10-01

Human thoracic dynamic responses and injuries associated with frontal impact, side impact, and belt loading were investigated and predicted using a complete human body finite element model for an average adult male. The human body model was developed to study the impact biomechanics of a vehicular occupant. Its geometry was based on the Visible Human Project (National Library of Medicine) and the topographies from human body anatomical texts. The data was then scaled to an average adult male according to available biomechanical data from the literature. The model includes details of the head, neck, ribcage, abdomen, thoracic and lumbar spine, internal organs of the chest and abdomen, pelvis, and the upper and lower extremities. The present study is focused on the dynamic response and injuries of the thorax. The model was validated at various impact speeds by comparing predicted responses with available experimental cadaver data in frontal and side pendulum impacts, as well as belt loading. Model responses were compared with similar individual cadaver tests instead of using cadaver corridors because the large differences between the upper and lower bounds of the corridors may confound the model validation. The validated model was then used to study thorax dynamic responses and injuries in various simulated impact conditions. Parameters that could induce injuries such as force, deflection, and stress were computed from model simulations and were compared with previously proposed thoracic injury criteria to assess injury potential for the thorax. It has been shown that the model exhibited speed sensitive impact characteristics, and the compressibility of the internal organs significantly influenced the overall impact response in the simulated impact conditions. This study demonstrates that the development of a validated FE human body model could be useful for injury assessment in various cadaveric impacts reported in the literature. Internal organ injuries, which are

Assessing women's lacrosse head impacts using finite element modelling.

Science.gov (United States)

Clark, J Michio; Hoshizaki, T Blaine; Gilchrist, Michael D

2018-04-01

Recently studies have assessed the ability of helmets to reduce peak linear and rotational acceleration for women's lacrosse head impacts. However, such measures have had low correlation with injury. Maximum principal strain interprets loading curves which provide better injury prediction than peak linear and rotational acceleration, especially in compliant situations which create low magnitude accelerations but long impact durations. The purpose of this study was to assess head and helmet impacts in women's lacrosse using finite element modelling. Linear and rotational acceleration loading curves from women's lacrosse impacts to a helmeted and an unhelmeted Hybrid III headform were input into the University College Dublin Brain Trauma Model. The finite element model was used to calculate maximum principal strain in the cerebrum. The results demonstrated for unhelmeted impacts, falls and ball impacts produce higher maximum principal strain values than stick and shoulder collisions. The strain values for falls and ball impacts were found to be within the range of concussion and traumatic brain injury. The results also showed that men's lacrosse helmets reduced maximum principal strain for follow-through slashing, falls and ball impacts. These findings are novel and demonstrate that for high risk events, maximum principal strain can be reduced by implementing the use of helmets if the rules of the sport do not effectively manage such situations. Copyright © 2018 Elsevier Ltd. All rights reserved.

Post-heading heat stress and yield impact in winter wheat of China.

Science.gov (United States)

Liu, Bing; Liu, Leilei; Tian, Liying; Cao, Weixing; Zhu, Yan; Asseng, Senthold

2014-02-01

Wheat is sensitive to high temperatures, but the spatial and temporal variability of high temperature and its impact on yield are often not known. An analysis of historical climate and yield data was undertaken to characterize the spatial and temporal variability of heat stress between heading and maturity and its impact on wheat grain yield in China. Several heat stress indices were developed to quantify heat intensity, frequency, and duration between heading and maturity based on measured maximum temperature records of the last 50 years from 166 stations in the main wheat-growing region of China. Surprisingly, heat stress between heading and maturity was more severe in the generally cooler northern wheat-growing regions than the generally warmer southern regions of China, because of the delayed time of heading with low temperatures during the earlier growing season and the exposure of the post-heading phase into the warmer part of the year. Heat stress between heading and maturity has increased in the last decades in most of the main winter wheat production areas of China, but the rate was higher in the south than in the north. The correlation between measured grain yields and post-heading heat stress and average temperature were statistically significant in the entire wheat-producing region, and explained about 29% of the observed spatial and temporal yield variability. A heat stress index considering the duration and intensity of heat between heading and maturity was required to describe the correlation of heat stress and yield variability. Because heat stress is a major cause of yield loss and the number of heat events is projected to increase in the future, quantifying the future impact of heat stress on wheat production and developing appropriate adaptation and mitigation strategies are critical for developing food security policies in China and elsewhere. © 2013 John Wiley & Sons Ltd.

THREE DIMENSIONAL DIGITIZATION OF HUMAN HEAD BY FUSING STRUCTURED LIGHT AND CONTOURS

Institute of Scientific and Technical Information of China (English)

Jin Gang; Li Dehua; Hu Hanping; Hu Bing

2002-01-01

Three dimensional digitization of human head is desired in many applications. In this paper, an information fusion based scheme is presented to obtain 3-D information of human head. Structured light technology is employed to measure depth. For the special reflection areas,in which the structured light stripe can not be detected directly, the shape of the structured light stripe can be calculated from the corresponding contour. By fusing the information of structured light and the contours, the problem of reflectance influence is solved, and the whole shape of head,including hair area, can be obtained. Some good results are obtained.

Head injury causation scenarios for belted, rear-seated children in frontal impacts.

Science.gov (United States)

Bohman, Katarina; Arbogast, Kristy B; Bostrom, Ola

2011-02-01

Head injuries are the most common serious injuries sustained by children in motor vehicle crashes and are of critical importance with regard to long-term disability. There is a lack of understanding of how seat belt-restrained children sustain head injuries in frontal impacts. The aim of the study was to identify the AIS2+ head injury causation scenarios for rear-seated, belt-restrained children in frontal impacts, including the set of parameters contributing to the injury. In-depth crash investigations from two National Highway Traffic Safety Administration (NHTSA) databases, the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS; 1997-2008) and the Crash Injury Research and Engineering Network (CIREN; 1996-2009), were collected and analyzed in detail. Selection criteria were all frontal impacts with principal direction of force (PDOF) of 11, 12, and 1 o'clock involving rear-seated, three-point belt-restrained, with or without booster cushion, children from 3 to 13 years with an AIS2+ head injury. Cases were analyzed using the BioTab method of injury causation assessment in order to systematically analyze the injury causation scenario for each case. There were 27 cases meeting the inclusion criteria, 19 cases with MAIS2 head injuries and 8 cases with MAIS3+ head injuries, including 2 fatalities. Three major injury causation scenarios were identified, including head contact with seatback (10 cases), head contact with side interior (7 cases,) and no evidence of head contact (9 cases). Head injuries with seatback or side interior contact typically included a PDOF greater than 10 degree (similar to the Insurance Institute for Highway Safety [IIHS] and EuroNCAP offset frontal testing) and vehicle maneuvers. For seatback contact, the vehicle's movements contributed to occupant kinematics inboard the vehicle, causing a less than optimal restraint of the torso and/or torso roll out of the shoulder belt. For side interior contact, the PDOF and

Growth trajectories of the human embryonic head and periconceptional maternal conditions.

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Koning, I V; Baken, L; Groenenberg, I A L; Husen, S C; Dudink, J; Willemsen, S P; Gijtenbeek, M; Koning, A H J; Reiss, I K M; Steegers, E A P; Steegers-Theunissen, R P M

2016-05-01

Can growth trajectories of the human embryonic head be created using 3D ultrasound (3D-US) and virtual reality (VR) technology, and be associated with second trimester fetal head size and periconceptional maternal conditions? Serial first trimester head circumference (HC) and head volume (HV) measurements were used to create reliable growth trajectories of the embryonic head, which were significantly associated with fetal head size and periconceptional maternal smoking, age and ITALIC! in vitro fertilization (IVF)/intra-cytoplasmic sperm injection (ICSI) treatment. Fetal growth is influenced by periconceptional maternal conditions. We selected 149 singleton pregnancies with a live born non-malformed fetus from the Rotterdam periconception cohort. Bi-parietal diameter and occipital frontal diameter to calculate HC, HV and crown-rump length (CRL) were measured weekly between 9 + 0 and 12 + 6 weeks gestational age (GA) using 3D-US and VR. Fetal HC was obtained from second trimester structural anomaly scans. Growth trajectories of the embryonic head were created with general additive models and linear mixed models were used to estimate associations with maternal periconceptional conditions as a function of GA and CRL, respectively. A total of 303 3D-US images of 149 pregnancies were eligible for embryonic head measurements (intra-class correlation coefficients >0.99). Associations were found between embryonic HC and fetal HC ( ITALIC! ρ = 0.617, ITALIC! P head measured by HC and HV (All ITALIC! P head may be of benefit in future early antenatal care. This study was funded by the Department of Obstetrics and Gynaecology, Erasmus MC University Medical Centre and Sophia Foundation for Medical Research, Rotterdam, The Netherlands (SSWO grant number 644). No competing interests are declared. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email

Heading and head injuries in soccer.

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Kirkendall, D T; Jordan, S E; Garrett, W E

2001-01-01

In the world of sports, soccer is unique because of the purposeful use of the unprotected head for controlling and advancing the ball. This skill obviously places the player at risk of head injury and the game does carry some risk. Head injury can be a result of contact of the head with another head (or other body parts), ground, goal post, other unknown objects or even the ball. Such impacts can lead to contusions, fractures, eye injuries, concussions or even, in rare cases, death. Coaches, players, parents and physicians are rightly concerned about the risk of head injury in soccer. Current research shows that selected soccer players have some degree of cognitive dysfunction. It is important to determine the reasons behind such deficits. Purposeful heading has been blamed, but a closer look at the studies that focus on heading has revealed methodological concerns that question the validity of blaming purposeful heading of the ball. The player's history and age (did they play when the ball was leather and could absorb significant amounts of water), alcohol intake, drug intake, learning disabilities, concussion definition and control group use/composition are all factors that cloud the ability to blame purposeful heading. What does seem clear is that a player's history of concussive episodes is a more likely explanation for cognitive deficits. While it is likely that the subconcussive impact of purposeful heading is a doubtful factor in the noted deficits, it is unknown whether multiple subconcussive impacts might have some lingering effects. In addition, it is unknown whether the noted deficits have any affect on daily life. Proper instruction in the technique is critical because if the ball contacts an unprepared head (as in accidental head-ball contacts), the potential for serious injury is possible. To further our understanding of the relationship of heading, head injury and cognitive deficits, we need to: learn more about the actual impact of a ball on the

Why infest the loved ones--inherent human behaviour indicates former mutualism with head lice.

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Rózsa, Lajos; Apari, Péter

2012-05-01

Head lice transmit to new hosts when people lean their heads together. Humans frequently touch their heads to express friendship or love, while this behaviour is absent in apes. We hypothesize that this behaviour was adaptive because it enabled people to acquire head lice infestations as early as possible to provoke an immune response effective against both head lice and body lice throughout the subsequent periods of their life. This cross-immunity could provide some defence against the body-louse-borne lethal diseases like epidemic typhus, trench fever, relapsing fever and the classical plague. Thus the human 'touching heads' behaviour probably acts as an inherent and unconscious 'vaccination' against body lice to reduce the threat exposed by the pathogens they may transmit. Recently, the eradication of body-louse-borne diseases rendered the transmission of head lice a maladaptive, though still widespread, behaviour in developed societies.

Head Start’s Impact is Contingent on Alternative Type of Care in Comparison Group

Science.gov (United States)

Brooks-Gunn, Jeanne; Waldfogel, Jane

2014-01-01

Using data (n = 3,790 with 2,119 in the 3-year-old cohort and 1,671 in the 4-year-old cohort) from 353 Head Start centers in the Head Start Impact Study, the only large-scale randomized experiment in Head Start history, this paper examined the impact of Head Start on children’s cognitive and parent-reported social-behavioral outcomes through first grade contingent on the child care arrangements used by children who were randomly assigned to the control group (i.e., parental care, relative/non-relative care, another Head Start program, or other center-based care). A principal score matching approach was adopted to identify children assigned to Head Start who were similar to children in the control group with a specific care arrangement. Overall, the results showed that the effects of Head Start varied substantially contingent on the alternative child care arrangements. Compared to children in parental care and relative/non-relative care, Head Start participants generally had better cognitive and parent-reported behavioral development, with some benefits of Head Start persisting through first grade; in contrast, few differences were found between Head Start and other center-based care. The results have implications regarding the children for whom Head Start is most beneficial as well as how well Head Start compares to other center-based programs. PMID:25329552

The impact of gravity during head-up tilt

DEFF Research Database (Denmark)

Ottesen, Johnny T.; Olufsen, Mette; Smith, Brittany

2011-01-01

The impact of gravity during head-up tilt, a test often used in the clinic to diagnose patients who suffer from dizziness or frequent episodes of syncope, is not well described. This study uses mathematical modeling to analyze experimental blood pressure data measured at the level of the aorta an...

Head Impact Exposure in Youth Football: Comparing Age- and Weight-Based Levels of Play.

Science.gov (United States)

Kelley, Mireille E; Urban, Jillian E; Miller, Logan E; Jones, Derek A; Espeland, Mark A; Davenport, Elizabeth M; Whitlow, Christopher T; Maldjian, Joseph A; Stitzel, Joel D

2017-06-01

Approximately 5,000,000 athletes play organized football in the United States, and youth athletes constitute the largest proportion with ∼3,500,000 participants. Investigations of head impact exposure (HIE) in youth football have been limited in size and duration. The objective of this study was to evaluate HIE of athletes participating in three age- and weight-based levels of play within a single youth football organization over four seasons. Head impact data were collected using the Head Impact Telemetry (HIT) System. Mixed effects linear models were fitted, and Wald tests were used to assess differences in head accelerations and number of impacts among levels and session type (competitions vs. practices). The three levels studied were levels A (n = 39, age = 10.8 ± 0.7 years, weight = 97.5 ± 11.8 lb), B (n = 48, age = 11.9 ± 0.5 years, weight = 106.1 ± 13.8 lb), and C (n = 32, age = 13.0 ± 0.5 years, weight = 126.5 ± 18.6 lb). A total of 40,538 head impacts were measured. The median/95th percentile linear head acceleration for levels A, B, and C was 19.8/49.4g, 20.6/51.0g, and 22.0/57.9g, respectively. Level C had significantly greater mean linear acceleration than both levels A (p = 0.005) and B (p = 0.02). There were a significantly greater number of impacts per player in a competition than in a practice session for all levels (A, p = 0.0005, B, p = 0.0019, and C, p football and are an important step in making evidence-based decisions to reduce HIE.

Animation of 3D Model of Human Head

Directory of Open Access Journals (Sweden)

V. Michalcin

2007-04-01

Full Text Available The paper deals with the new algorithm of animation of 3D model of the human head in combination with its global motion. The designed algorithm is very fast and with low calculation requirements, because it does not need the synthesis of the input videosequence for estimation of the animation parameters as well as the parameters of global motion. The used 3D model Candide generates different expressions using its animation units which are controlled by the animation parameters. These ones are estimated on the basis of optical flow without the need of extracting of the feature points in the frames of the input videosequence because they are given by the selected vertices of the animation units of the calibrated 3D model Candide. The established multiple iterations inside the designed animation algorithm of 3D model of the human head between two successive frames significantly improved its accuracy above all for the large motion.

Genotyping of human lice suggests multiple emergencies of body lice from local head louse populations.

Directory of Open Access Journals (Sweden)

Wenjun Li

Full Text Available BACKGROUND: Genetic analyses of human lice have shown that the current taxonomic classification of head lice (Pediculus humanus capitis and body lice (Pediculus humanus humanus does not reflect their phylogenetic organization. Three phylotypes of head lice A, B and C exist but body lice have been observed only in phylotype A. Head and body lice have different behaviours and only the latter have been involved in outbreaks of infectious diseases including epidemic typhus, trench fever and louse borne recurrent fever. Recent studies suggest that body lice arose several times from head louse populations. METHODS AND FINDINGS: By introducing a new genotyping technique, sequencing variable intergenic spacers which were selected from louse genomic sequence, we were able to evaluate the genotypic distribution of 207 human lice. Sequence variation of two intergenic spacers, S2 and S5, discriminated the 207 lice into 148 genotypes and sequence variation of another two intergenic spacers, PM1 and PM2, discriminated 174 lice into 77 genotypes. Concatenation of the four intergenic spacers discriminated a panel of 97 lice into 96 genotypes. These intergenic spacer sequence types were relatively specific geographically, and enabled us to identify two clusters in France, one cluster in Central Africa (where a large body louse outbreak has been observed and one cluster in Russia. Interestingly, head and body lice were not genetically differentiated. CONCLUSIONS: We propose a hypothesis for the emergence of body lice, and suggest that humans with both low hygiene and head louse infestations provide an opportunity for head louse variants, able to ingest a larger blood meal (a required characteristic of body lice, to colonize clothing. If this hypothesis is ultimately supported, it would help to explain why poor human hygiene often coincides with outbreaks of body lice. Additionally, if head lice act as a reservoir for body lice, and that any social degradation in

Muecas: A Multi-Sensor Robotic Head for Affective Human Robot Interaction and Imitation

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Felipe Cid

2014-04-01

Full Text Available This paper presents a multi-sensor humanoid robotic head for human robot interaction. The design of the robotic head, Muecas, is based on ongoing research on the mechanisms of perception and imitation of human expressions and emotions. These mechanisms allow direct interaction between the robot and its human companion through the different natural language modalities: speech, body language and facial expressions. The robotic head has 12 degrees of freedom, in a human-like configuration, including eyes, eyebrows, mouth and neck, and has been designed and built entirely by IADeX (Engineering, Automation and Design of Extremadura and RoboLab. A detailed description of its kinematics is provided along with the design of the most complex controllers. Muecas can be directly controlled by FACS (Facial Action Coding System, the de facto standard for facial expression recognition and synthesis. This feature facilitates its use by third party platforms and encourages the development of imitation and of goal-based systems. Imitation systems learn from the user, while goal-based ones use planning techniques to drive the user towards a final desired state. To show the flexibility and reliability of the robotic head, the paper presents a software architecture that is able to detect, recognize, classify and generate facial expressions in real time using FACS. This system has been implemented using the robotics framework, RoboComp, which provides hardware-independent access to the sensors in the head. Finally, the paper presents experimental results showing the real-time functioning of the whole system, including recognition and imitation of human facial expressions.

Laboratory Evaluation of Low-Cost Wearable Sensors for Measuring Head Impacts in Sports.

Science.gov (United States)

Tyson, Abigail M; Duma, Stefan M; Rowson, Steven

2018-04-03

Advances in low-cost wearable head impact sensor technology provide potential benefits regarding sports safety for both consumers and researchers. However, previous laboratory evaluations are not directly comparable and don't incorporate test conditions representative of unhelmeted impacts. This study addresses those limitations. The xPatch by X2 Biosystems and the SIM-G by Triax Technologies were placed on a NOCSAE headform with a Hybrid III neck which underwent impacts tests using a pendulum. Impact conditions included helmeted, padded impactor to bare head, and rigid impactor to bare head to represent long and short-duration impacts seen in helmeted and unhelmeted sports. The wearable sensors were evaluated on their kinematic accuracy by comparing results to reference sensors located at the headform center of gravity. Statistical tests for equivalence were performed on the slope of the linear regression between wearable sensors and reference. The xPatch gave equivalent measurements to the reference in select longer-duration impacts whereas the SIM-G had large variance leading to no equivalence. For the short-duration impacts, both wearable sensors underpredicted the reference. This error can be improved with increases in sampling rate from 1 to 1.5 kHz. Follow-up evaluations should be performed on the field to identify error in vivo. (197/200).

A novel device for head gesture measurement system in combination with eye-controlled human machine interface

Science.gov (United States)

Lin, Chern-Sheng; Ho, Chien-Wa; Chang, Kai-Chieh; Hung, San-Shan; Shei, Hung-Jung; Yeh, Mau-Shiun

2006-06-01

This study describes the design and combination of an eye-controlled and a head-controlled human-machine interface system. This system is a highly effective human-machine interface, detecting head movement by changing positions and numbers of light sources on the head. When the users utilize the head-mounted display to browse a computer screen, the system will catch the images of the user's eyes with CCD cameras, which can also measure the angle and position of the light sources. In the eye-tracking system, the program in the computer will locate each center point of the pupils in the images, and record the information on moving traces and pupil diameters. In the head gesture measurement system, the user wears a double-source eyeglass frame, so the system catches images of the user's head by using a CCD camera in front of the user. The computer program will locate the center point of the head, transferring it to the screen coordinates, and then the user can control the cursor by head motions. We combine the eye-controlled and head-controlled human-machine interface system for the virtual reality applications.

The immunologic considerations in human head transplantation.

Science.gov (United States)

Hardy, Mark A; Furr, Allen; Barret, Juan P; Barker, John H

2017-05-01

The idea of head transplantation appears at first as unrealistic, unethical, and futile. Here we discuss immunological considerations in human head transplantation. In a separate accompanying article we discuss surgical, ethical, and psychosocial issues concerned in body-to-head transplantation (BHT) [1]. The success of such an unusual allograft, where the donor and the recipient can reject each other, depends on prevention of complex immunologic reactions, especially rejection of the head by the body (graft-vs-host) or probably less likely, the possibility of the head rejecting the total body allograft (host-vs-graft). The technical and immunologic difficulties are enormous, especially since rapid nerve and cord connections and regeneration have not yet been possible to achieve. In this article we begin by briefly reviewing neuro-immunologic issues that may favor BHT such as the blood brain barrier (BBB) and point out its shortcomings. And we touch on the cellular and humoral elements in the brain proper that differ in some respects from those in other organs and in the periphery. Based on recent successes in vascular composite allografts (VCAs), we will elaborate on potential specific advantages and difficulties in BHT of various available immunosuppressive medications already utilized in VCAs. The risk/benefit ratio of these drugs will be emphasized in relation to direct brain toxicity such as seizure disorders, interference, or promotion of nerve regeneration, and potentiation of cerebral viral infections. The final portion of this article will focus on pre-transplant immunologic manipulation of the deceased donor body along with pretreatment of the recipient. Copyright © 2017 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

Head Pose Estimation Using Multilinear Subspace Analysis for Robot Human Awareness

Science.gov (United States)

Ivanov, Tonislav; Matthies, Larry; Vasilescu, M. Alex O.

2009-01-01

Mobile robots, operating in unconstrained indoor and outdoor environments, would benefit in many ways from perception of the human awareness around them. Knowledge of people's head pose and gaze directions would enable the robot to deduce which people are aware of the its presence, and to predict future motions of the people for better path planning. To make such inferences, requires estimating head pose on facial images that are combination of multiple varying factors, such as identity, appearance, head pose, and illumination. By applying multilinear algebra, the algebra of higher-order tensors, we can separate these factors and estimate head pose regardless of subject's identity or image conditions. Furthermore, we can automatically handle uncertainty in the size of the face and its location. We demonstrate a pipeline of on-the-move detection of pedestrians with a robot stereo vision system, segmentation of the head, and head pose estimation in cluttered urban street scenes.

The RID2 biofidelic rear impact dummy: a pilot study using human subjects in low speed rear impact full scale crash tests.

Science.gov (United States)

Croft, Arthur C; Philippens, Mathieu M G M

2007-03-01

Human subjects and the recently developed RID2 rear impact crash test dummy were exposed to a series of full scale, vehicle-to-vehicle crash tests. To evaluate the biofidelity of the RID2 anthropometric test dummy on the basis of calculated neck injury criterion (NIC) values by comparing these values to those obtained from human subjects exposed in the very same crashes. The widely used and familiar hybrid III dummy has been said to lack biofidelity in the special application of low speed rear impact crashes. Several attempts have been made to modify this dummy with only marginal success. Two completely new dummies have been developed; the BioRID and the RID2. Neither have been tested under real world crash boundary conditions in side-by-side comparisons with live human subjects. Volunteer subjects, including a 50th percentile male, a 95th percentile male, and a 50th percentile female, were placed in the driver's seat of a vehicle and subjected to a series of three low speed rear impact crashes each. The RID2 dummy, which is modeled after a 50th percentile male, was placed in the passenger seat in each case. Both subjects and dummy were fully instrumented and acceleration-time histories were recorded. From this data, velocities of the heads and torsos were determined and both were used to calculate the NIC values for both crash test subjects and the RID2. The RID2 demonstrated generally higher head accelerations and NIC values than those of the human subjects. Most of the observed variations might be explained on the basis of differing head restraint geometry, posture, and body size. The RID2 NIC values compared most favorably with those of the 50th percentile male subject. For the whole group, the correlations between RID2 and human subjects did not reach statistical significance. The small number of test subjects and crash tests limited the statistical power of this pilot study, and the correlation between the RID2 and human subject NIC values were not

Cross-sectional evaluation of visuomotor tracking performance following subconcussive head impacts.

Science.gov (United States)

Brokaw, E B; Fine, M S; Kindschi, K E; Santago Ii, A C; Lum, P S; Higgins, M

2018-01-01

Repeated mild traumatic brain injury (mTBI) has been associated with increased risk of degenerative neurological disorders. While the effects of mTBI and repeated injury are known, studies have only recently started examining repeated subconcussive impacts, impacts that do not result in a clinically diagnosed mTBI. In these studies, repeated subconcussive impacts have been connected to cognitive performance and brain imaging changes. Recent research suggests that performance on a visuomotor tracking (VMT) task may help improve the identification of mTBI. The goal of this study was to investigate if VMT performance is sensitive to the cumulative effect of repeated subconcussive head impacts in collegiate men's lacrosse players. A cross-sectional, prospective study was completed with eleven collegiate men's lacrosse players. Participants wore helmet-mounted sensors and completed VMT and reaction time assessments. The relationship between cumulative impact metrics and VMT metrics were investigated. In this study, VMT performance correlated with repeated subconcussive head impacts; individuals approached clinically diagnosed mTBI-like performance as the cumulative rotational velocity they experienced increased. This suggests that repeated subconcussive impacts can result in measurable impairments and indicates that visuomotor tracking performance may be a useful tool for monitoring the effects of repeated subconcussive impacts.

Probabilistic Mapping of Human Visual Attention from Head Pose Estimation

Directory of Open Access Journals (Sweden)

Andrea Veronese

2017-10-01

Full Text Available Effective interaction between a human and a robot requires the bidirectional perception and interpretation of actions and behavior. While actions can be identified as a directly observable activity, this might not be sufficient to deduce actions in a scene. For example, orienting our face toward a book might suggest the action toward “reading.” For a human observer, this deduction requires the direction of gaze, the object identified as a book and the intersection between gaze and book. With this in mind, we aim to estimate and map human visual attention as directed to a scene, and assess how this relates to the detection of objects and their related actions. In particular, we consider human head pose as measurement to infer the attention of a human engaged in a task and study which prior knowledge should be included in such a detection system. In a user study, we show the successful detection of attention to objects in a typical office task scenario (i.e., reading, working with a computer, studying an object. Our system requires a single external RGB camera for head pose measurements and a pre-recorded 3D point cloud of the environment.

SAR in human head model due to resonant wireless power transfer system.

Science.gov (United States)

Zhang, Chao; Liu, Guoqiang; Li, Yanhong; Song, Xianjin

2016-04-29

Efficient mid-range wireless power transfer between transmitter and the receiver has been achieved based on the magnetic resonant coupling method. The influence of electromagnetic field on the human body due to resonant wireless power transfer system (RWPT) should be taken into account during the design process of the system. To analyze the transfer performance of the RWPT system and the change rules of the specific absorption rate (SAR) in the human head model due to the RWPT system. The circuit-field coupling method for a RWPT system with consideration of the displacement current was presented. The relationship between the spiral coil parameters and transfer performance was studied. The SAR in the human head model was calculated under two different exposure conditions. A system with output power higher than 10 W at 0.2 m distance operating at a frequency of approximately 1 MHz was designed. The FEM simulation results show the peak SAR value is below the safety limit which appeared when the human head model is in front of the transmitter. The simulation results agreed well with the experimental results, which verified the validity of the analysis and design.

Effect of ice surface size on collision rates and head impacts at the World Junior Hockey Championships, 2002 to 2004.

Science.gov (United States)

Wennberg, Richard

2005-03-01

To determine if collision rates and head impacts in elite junior hockey differed between games played on the small North American ice surface (85 ft wide), an intermediate-size Finnish ice surface (94 ft wide), and the large standard international ice surface (100 ft wide). Videotape analysis of all games involving Team Canada from the 2002 (large ice, Czech Republic), 2003 (small ice, Canada), and 2004 (intermediate ice, Finland) World Junior Championships. All collisions were counted and separated into various categories (volitional player/player bodychecks, into boards or open ice, plus accidental/incidental player/boards, player/ice, head/stick, head/puck). Further subdivisions included collisions involving the head directly or indirectly and notably severe head impacts. Small, intermediate, and large ice surface mean collisions/game, respectively, were 295, 258, 222, total collisions; 251, 220, 181, volitional bodychecks; 126, 115, 88, into boards; 125, 106, 93, open ice; 71, 52, 44, total head; 44, 36, 30, indirect head; 26, 16, 13, direct head; and 1.3, 0.5, 0.3, severe head (P < 0.05 for small-intermediate ice and intermediate-large ice differences in total collisions; P < 0.005 for small-large ice difference; P < 0.05 for small-intermediate ice differences in head impacts; P < 0.01 for small-large ice differences in total and severe head impacts). There is a significant inverse correlation between ice size and collision rates in elite hockey, including direct, indirect, and severe head impacts. These findings suggest that uniform usage of the larger international rinks could reduce the risk of injury, and specifically, concussions in elite hockey by decreasing the occurrence of collisions and head impacts.

Effects of External Loads on Human Head Movement Control Systems

Science.gov (United States)

Nam, M. H.; Choi, O. M.

1984-01-01

The central and reflexive control strategies underlying movements were elucidated by studying the effects of external loads on human head movement control systems. Some experimental results are presented on dynamic changes weigh the addition of aviation helmet (SPH4) and lead weights (6 kg). Intended time-optimal movements, their dynamics and electromyographic activity of neck muscles in normal movements, and also in movements made with external weights applied to the head were measured. It was observed that, when the external loads were added, the subject went through complex adapting processes and the head movement trajectory and its derivatives reached steady conditions only after transient adapting period. The steady adapted state was reached after 15 to 20 seconds (i.e., 5 to 6 movements).

Development and Validation of the Total HUman Model for Safety (THUMS) Version 5 Containing Multiple 1D Muscles for Estimating Occupant Motions with Muscle Activation During Side Impacts.

Science.gov (United States)

Iwamoto, Masami; Nakahira, Yuko

2015-11-01

Accurate prediction of occupant head kinematics is critical for better understanding of head/face injury mechanisms in side impacts, especially far-side occupants. In light of the fact that researchers have demonstrated that muscle activations, especially in neck muscles, can affect occupant head kinematics, a human body finite element (FE) model that considers muscle activation is useful for predicting occupant head kinematics in real-world automotive accidents. In this study, we developed a human body FE model called the THUMS (Total HUman Model for Safety) Version 5 that contains 262 one-dimensional (1D) Hill-type muscle models over the entire body. The THUMS was validated against 36 series of PMHS (Post Mortem Human Surrogate) and volunteer test data in this study, and 16 series of PMHS and volunteer test data on side impacts are presented. Validation results with force-time curves were also evaluated quantitatively using the CORA (CORrelation and Analysis) method. The validation results suggest that the THUMS has good biofidelity in the responses of the regional or full body for side impacts, but relatively poor biofidelity in its local level of responses such as brain displacements. Occupant kinematics predicted by the THUMS with a muscle controller using 22 PID (Proportional-Integral- Derivative) controllers were compared with those of volunteer test data on low-speed lateral impacts. The THUMS with muscle controller reproduced the head kinematics of the volunteer data more accurately than that without muscle activation, although further studies on validation of torso kinematics are needed for more accurate predictions of occupant head kinematics.

Correlation of Head Impacts to Change in Balance Error Scoring System Scores in Division I Men's Lacrosse Players.

Science.gov (United States)

Miyashita, Theresa L; Diakogeorgiou, Eleni; Marrie, Kaitlyn

Investigation into the effect of cumulative subconcussive head impacts has yielded various results in the literature, with many supporting a link to neurological deficits. Little research has been conducted on men's lacrosse and associated balance deficits from head impacts. (1) Athletes will commit more errors on the postseason Balance Error Scoring System (BESS) test. (2) There will be a positive correlation to change in BESS scores and head impact exposure data. Prospective longitudinal study. Level 3. Thirty-four Division I men's lacrosse players (age, 19.59 ± 1.42 years) wore helmets instrumented with a sensor to collect head impact exposure data over the course of a competitive season. Players completed a BESS test at the start and end of the competitive season. The number of errors from pre- to postseason increased during the double-leg stance on foam ( P impacts sustained over the course of 1 lacrosse season, as measured by average linear acceleration, head injury criteria, and Gadd Severity Index scores. If there is microtrauma to the vestibular system due to repetitive subconcussive impacts, only an assessment that highly stresses the vestibular system may be able to detect these changes. Cumulative subconcussive impacts may result in neurocognitive dysfunction, including balance deficits, which are associated with an increased risk for injury. The development of a strategy to reduce total number of head impacts may curb the associated sequelae. Incorporation of a modified BESS test, firm surface only, may not be recommended as it may not detect changes due to repetitive impacts over the course of a competitive season.

Predicting brain acceleration during heading of soccer ball

Science.gov (United States)

Taha, Zahari; Hasnun Arif Hassan, Mohd; Azri Aris, Mohd; Anuar, Zulfika

2013-12-01

There has been a long debate whether purposeful heading could cause harm to the brain. Studies have shown that repetitive heading could lead to degeneration of brain cells, which is similarly found in patients with mild traumatic brain injury. A two-degree of freedom linear mathematical model was developed to study the impact of soccer ball to the brain during ball-to-head impact in soccer. From the model, the acceleration of the brain upon impact can be obtained. The model is a mass-spring-damper system, in which the skull is modelled as a mass and the neck is modelled as a spring-damper system. The brain is a mass with suspension characteristics that are also defined by a spring and a damper. The model was validated by experiment, in which a ball was dropped from different heights onto an instrumented dummy skull. The validation shows that the results obtained from the model are in a good agreement with the brain acceleration measured from the experiment. This findings show that a simple linear mathematical model can be useful in giving a preliminary insight on what human brain endures during a ball-to-head impact.

Feasibility and implementation of a literature information management system for human papillomavirus in head and neck cancers with imaging.

Science.gov (United States)

Wu, Dee H; Matthiesen, Chance L; Alleman, Anthony M; Fournier, Aaron L; Gunter, Tyler C

2014-01-01

This work examines the feasibility and implementation of information service-orientated architecture (ISOA) on an emergent literature domain of human papillomavirus, head and neck cancer, and imaging. From this work, we examine the impact of cancer informatics and generate a full set of summarizing clinical pearls. Additionally, we describe how such an ISOA creates potential benefits in informatics education, enhancing utility for creating enduring digital content in this clinical domain.

Enrico Chiaveri, new Head of the Human Resources Department

CERN Document Server

2005-01-01

Enrico Chiaveri has been appointed Head of the Human Resources Department of with effect from 1st April 2005. A senior physicist, Dr Chiaveri joined CERN in 1973. During his career, he has performed various management roles, including that of Deputy Leader of the SPS/LEP Division, and has acquired extensive experience in human resources matters. Over the transition period up to 1st August 2005 he will gradually relinquish his current functions as Group Leader within the AB Department.

Human Papilloma Virus (HPV) Induced Head & Neck Squamous Cell Carcinoma: A Comprehensive Retrospect

Science.gov (United States)

Nishat, Roquaiya; Ramachandra, Sujatha; Kumar, Harish; Bandyopadhyay, Alokenath

2015-01-01

Head and Neck Squamous Cell Carcinoma accounts for the sixth most common malignancy occurring worldwide with tobacco and alcohol being the two well established risk factors. In the recent years, substantial evidence has been obtained that Human Papilloma Virus (HPV) associated head and neck cancers are on the rise. This article provides an insight into the structure of HPV genome, molecular pathogenesis, detection methods and clinical implications of HPV positive Head and Neck Squamous Cell Carcinoma. PMID:26266234

A structurally detailed finite element human head model for simulation of transcranial magnetic stimulation.

Science.gov (United States)

Chen, Ming; Mogul, David Jeffery

2009-04-30

Computational studies of the head utilizing finite element models (FEMs) have been used to investigate a wide variety of brain-electromagnetic (EM) field interaction phenomena including magnetic stimulation of the head using transcranial magnetic stimulation (TMS), direct electric stimulation of the brain for electroconvulsive therapy, and electroencephalography source localization. However, no human head model of sufficient complexity for studying the biophysics under these circumstances has been developed which utilizes structures at both the regional and cellular levels and provides well-defined smooth boundaries between tissues of different conductivities and orientations. The main barrier for building such accurate head models is the complex modeling procedures that include 3D object reconstruction and optimized meshing. In this study, a structurally detailed finite element model of the human head was generated that includes details to the level of cerebral gyri and sulci by combining computed tomography and magnetic resonance images. Furthermore, cortical columns that contain conductive processes of pyramidal neurons traversing the neocortical layers were included in the head model thus providing structure at or near the cellular level. These refinements provide a much more realistic model to investigate the effects of TMS on brain electrophysiology in the neocortex.

Cleveland Clinic intelligent mouthguard: a new technology to accurately measure head impact in athletes and soldiers

Science.gov (United States)

Bartsch, Adam; Samorezov, Sergey

2013-05-01

Nearly 2 million Traumatic Brain Injuries (TBI) occur in the U.S. each year, with societal costs approaching $60 billion. Including mild TBI and concussion, TBI's are prevalent in soldiers returning from Iraq and Afghanistan as well as in domestic athletes. Long-term risks of single and cumulative head impact dosage may present in the form of post traumatic stress disorder (PTSD), depression, suicide, Chronic Traumatic Encephalopathy (CTE), dementia, Alzheimer's and Parkinson's diseases. Quantifying head impact dosage and understanding associated risk factors for the development of long-term sequelae is critical toward developing guidelines for TBI exposure and post-exposure management. The current knowledge gap between head impact exposure and clinical outcomes limits the understanding of underlying TBI mechanisms, including effective treatment protocols and prevention methods for soldiers and athletes. In order to begin addressing this knowledge gap, Cleveland Clinic is developing the "Intelligent Mouthguard" head impact dosimeter. Current testing indicates the Intelligent Mouthguard can quantify linear acceleration with 3% error and angular acceleration with 17% error during impacts ranging from 10g to 174g and 850rad/s2 to 10000rad/s2, respectively. Correlation was high (R2 > 0.99, R2 = 0.98, respectively). Near-term development will be geared towards quantifying head impact dosages in vitro, longitudinally in athletes and to test new sensors for possible improved accuracy and reduced bias. Long-term, the IMG may be useful to soldiers to be paired with neurocognitive clinical data quantifying resultant TBI functional deficits.

Economic impact of a head and neck oncologic surgeon: the case mix index.

Science.gov (United States)

Jalisi, Scharukh; Sanan, Akshay; Mcdonough, Katie; Hussein, Khalil; Platt, Michael; Truong, Minh Tam; Couch, Marion; Burkey, Brian B

2014-10-01

Head and neck oncologic surgery is a time-consuming specialty that requires extensive resources and manpower. Case mix index (CMI) is used in evaluating the complexity and economic impact of surgeons. Head and neck oncologic surgeons generate significant revenue for hospitals, yet compensation is relatively low. Retrospective review of a tertiary hospital's case mix data for 605 otolaryngology admissions from 2009 to 2011 was performed. CMI comparison for head and neck oncologic surgeons versus general otolaryngology was performed. In an otolaryngology department of 9 surgeons; there was a significant difference (p 1) favoring head and neck oncologic surgeons. Head and neck oncologic surgeons increase the CMI for hospitals and ultimately influence the hospital's reimbursement. There is a need for increased collaboration between hospitals and departments in fostering and furthering their head and neck surgical oncology programs by taking CMI into consideration. © 2013 Wiley Periodicals, Inc.

Quantifying Variation in Head Start Effects on Young Children's Cognitive and Socio-Emotional Skills Using Data from the National Head Start Impact Study

Science.gov (United States)

Bloom, Howard S.; Weiland, Christina

2015-01-01

This paper uses data from the Head Start Impact Study (HSIS), a nationally representative multisite randomized trial, to quantify variation in effects of Head Start during 2002-2003 on children's cognitive and socio-emotional outcomes relative to the effects of other local alternatives, including parent care. We find that (1) treatment and control…

The Impact of Head Start on Children, Families and Communities. Final Report of the Head Start Evaluation, Synthesis and Utilization Project. Executive Summary.

Science.gov (United States)

McKey, Ruth Hubbell; And Others

This report summarizes the results of a study on the impact of Head Start on children's cognitive and socioemotional development, on child health and health institutions in the community, on enrollees' families, and on communities where Head Start programs operate. After discussing the background and methodology of the study, the report concludes…

Blood flow and microdialysis in the human femoral head

DEFF Research Database (Denmark)

Bøgehøj, Morten; Emmeluth, Claus; Overgaard, Søren

2007-01-01

BACKGROUND: If it would be possible to detect lack of flow and/or the development of ischemia in bone, we might have a way of predicting whether a broken bone will heal. We established microdialysis (MD) and laser Doppler (LD) flow measurement in the human femoral head in order to be able to detect...

Exploring the mechanisms of vehicle front-end shape on pedestrian head injuries caused by ground impact.

Science.gov (United States)

Yin, Sha; Li, Jiani; Xu, Jun

2017-09-01

In pedestrian-vehicle accidents, pedestrians typically suffer from secondary impact with the ground after the primary contact with vehicles. However, information about the fundamental mechanism of pedestrian head injury from ground impact remains minimal, thereby hindering further improvement in pedestrian safety. This study addresses this issue by using multi-body modeling and computation to investigate the influence of vehicle front-end shape on pedestrian safety. Accordingly, a simulation matrix is constructed to vary bonnet leading-edge height, bonnet length, bonnet angle, and windshield angle. Subsequently, a set of 315 pedestrian-vehicle crash simulations are conducted using the multi-body simulation software MADYMO. Three vehicle velocities, i.e., 20, 30, and 40km/h, are set as the scenarios. Results show that the top governing factor is bonnet leading-edge height. The posture and head injury at the instant of head ground impact vary dramatically with increasing height because of the significant rise of the body bending point and the movement of the collision point. The bonnet angle is the second dominant factor that affects head-ground injury, followed by bonnet length and windshield angle. The results may elucidate one of the critical barriers to understanding head injury caused by ground impact and provide a solid theoretical guideline for considering pedestrian safety in vehicle design. Copyright © 2017 Elsevier Ltd. All rights reserved.

Persistent, Long-term Cerebral White Matter Changes after Sports-Related Repetitive Head Impacts

Science.gov (United States)

Bazarian, Jeffrey J.; Zhu, Tong; Zhong, Jianhui; Janigro, Damir; Rozen, Eric; Roberts, Andrew; Javien, Hannah; Merchant-Borna, Kian; Abar, Beau; Blackman, Eric G.

2014-01-01

Introduction Repetitive head impacts (RHI) sustained in contact sports are thought to be necessary for the long-term development of chronic traumatic encephalopathy (CTE). Our objectives were to: 1) characterize the magnitude and persistence of RHI-induced white matter (WM) changes; 2) determine their relationship to kinematic measures of RHI; and 3) explore their clinical relevance. Methods Prospective, observational study of 10 Division III college football players and 5 non-athlete controls during the 2011-12 season. All subjects underwent diffusion tensor imaging (DTI), physiologic, cognitive, and balance testing at pre-season (Time 1), post-season (Time 2), and after 6-months of no-contact rest (Time 3). Head impact measures were recorded using helmet-mounted accelerometers. The percentage of whole-brain WM voxels with significant changes in fractional anisotropy (FA) and mean diffusivity (MD) from Time 1 to 2, and Time 1 to 3 was determined for each subject and correlated to head impacts and clinical measures. Results Total head impacts for the season ranged from 431–1,850. No athlete suffered a clinically evident concussion. Compared to controls, athletes experienced greater changes in FA and MD from Time 1 to 2 as well as Time 1 to 3; most differences at Time 2 persisted to Time 3. Among athletes, the percentage of voxels with decreased FA from Time 1 to 2 was positively correlated with several helmet impact measures. The persistence of WM changes from Time 1 to 3 was also associated with changes in serum ApoA1 and S100B autoantibodies. WM changes were not consistently associated with cognition or balance. Conclusions A single football season of RHIs without clinically-evident concussion resulted in WM changes that correlated with multiple helmet impact measures and persisted following 6 months of no-contact rest. This lack of WM recovery could potentially contribute to cumulative WM changes with subsequent RHI exposures. PMID:24740265

'Goats that stare at men': dwarf goats alter their behaviour in response to human head orientation, but do not spontaneously use head direction as a cue in a food-related context.

Science.gov (United States)

Nawroth, Christian; von Borell, Eberhard; Langbein, Jan

2015-01-01

Recently, comparative research on the mechanisms and species-specific adaptive values of attributing attentive states and using communicative cues has gained increased interest, particularly in non-human primates, birds, and dogs. Here, we investigate these phenomena in a farm animal species, the dwarf goat (Capra aegagrus hircus). In the first experiment, we investigated the effects of different human head and body orientations, as well as human experimenter presence/absence, on the behaviour of goats in a food-anticipating paradigm. Over a 30-s interval, the experimenter engaged in one of four different postures or behaviours (head and body towards the subject-'Control', head to the side, head and body away from the subject, or leaving the room) before delivering a reward. We found that the level of subjects' active anticipatory behaviour was highest in the control condition and decreased with a decreasing level of attention paid to the subject by the experimenter. Additionally, goats 'stared' (i.e. stood alert) at the experimental set-up for significantly more time when the experimenter was present but paid less attention to the subject ('Head' and 'Back' condition) than in the 'Control' and 'Out' conditions. In a second experiment, the experimenter provided different human-given cues that indicated the location of a hidden food reward in a two-way object choice task. Goats were able to use both 'Touch' and 'Point' cues to infer the correct location of the reward but did not perform above the level expected by chance in the 'Head only' condition. We conclude that goats are able to differentiate among different body postures of a human, including head orientation; however, despite their success at using multiple physical human cues, they fail to spontaneously use human head direction as a cue in a food-related context.

Dynamic Response and Residual Helmet Liner Crush Using Cadaver Heads and Standard Headforms.

Science.gov (United States)

Bonin, S J; Luck, J F; Bass, C R; Gardiner, J C; Onar-Thomas, A; Asfour, S S; Siegmund, G P

2017-03-01

Biomechanical headforms are used for helmet certification testing and reconstructing helmeted head impacts; however, their biofidelity and direct applicability to human head and helmet responses remain unclear. Dynamic responses of cadaver heads and three headforms and residual foam liner deformations were compared during motorcycle helmet impacts. Instrumented, helmeted heads/headforms were dropped onto the forehead region against an instrumented flat anvil at 75, 150, and 195 J. Helmets were CT scanned to quantify maximum liner crush depth and crush volume. General linear models were used to quantify the effect of head type and impact energy on linear acceleration, head injury criterion (HIC), force, maximum liner crush depth, and liner crush volume and regression models were used to quantify the relationship between acceleration and both maximum crush depth and crush volume. The cadaver heads generated larger peak accelerations than all three headforms, larger HICs than the International Organization for Standardization (ISO), larger forces than the Hybrid III and ISO, larger maximum crush depth than the ISO, and larger crush volumes than the DOT. These significant differences between the cadaver heads and headforms need to be accounted for when attempting to estimate an impact exposure using a helmet's residual crush depth or volume.

Injuries of the head from backface deformation of ballistic protective helmets under ballistic impact.

Science.gov (United States)

Rafaels, Karin A; Cutcliffe, Hattie C; Salzar, Robert S; Davis, Martin; Boggess, Brian; Bush, Bryan; Harris, Robert; Rountree, Mark Steve; Sanderson, Ellory; Campman, Steven; Koch, Spencer; Dale Bass, Cameron R

2015-01-01

Modern ballistic helmets defeat penetrating bullets by energy transfer from the projectile to the helmet, producing helmet deformation. This deformation may cause severe injuries without completely perforating the helmet, termed "behind armor blunt trauma" (BABT). As helmets become lighter, the likelihood of larger helmet backface deformation under ballistic impact increases. To characterize the potential for BABT, seven postmortem human head/neck specimens wearing a ballistic protective helmet were exposed to nonperforating impact, using a 9 mm, full metal jacket, 124 grain bullet with velocities of 400-460 m/s. An increasing trend of injury severity was observed, ranging from simple linear fractures to combinations of linear and depressed fractures. Overall, the ability to identify skull fractures resulting from BABT can be used in forensic investigations. Our results demonstrate a high risk of skull fracture due to BABT and necessitate the prevention of BABT as a design factor in future generations of protective gear. © 2014 American Academy of Forensic Sciences.

Human Papillomavirus Induced Transformation in Cervical and Head and Neck Cancers

Energy Technology Data Exchange (ETDEWEB)

Adams, Allie K. [Cancer and Blood Diseases Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229 (United States); Wise-Draper, Trisha M. [Division of Hematology/Oncology, University of Cincinnati Medical Center, University of Cincinnati, Cincinnati, OH 45229 (United States); Wells, Susanne I., E-mail: Susanne.Wells@cchmc.org [Cancer and Blood Diseases Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229 (United States)

2014-09-15

Human papillomavirus (HPV) is one of the most widely publicized and researched pathogenic DNA viruses. For decades, HPV research has focused on transforming viral activities in cervical cancer. During the past 15 years, however, HPV has also emerged as a major etiological agent in cancers of the head and neck, in particular squamous cell carcinoma. Even with significant strides achieved towards the screening and treatment of cervical cancer, and preventive vaccines, cervical cancer remains the leading cause of cancer-associated deaths for women in developing countries. Furthermore, routine screens are not available for those at risk of head and neck cancer. The current expectation is that HPV vaccination will prevent not only cervical, but also head and neck cancers. In order to determine if previous cervical cancer models for HPV infection and transformation are directly applicable to head and neck cancer, clinical and molecular disease aspects must be carefully compared. In this review, we briefly discuss the cervical and head and neck cancer literature to highlight clinical and genomic commonalities. Differences in prognosis, staging and treatment, as well as comparisons of mutational profiles, viral integration patterns, and alterations in gene expression will be addressed.

Human Papillomavirus Induced Transformation in Cervical and Head and Neck Cancers

International Nuclear Information System (INIS)

Adams, Allie K.; Wise-Draper, Trisha M.; Wells, Susanne I.

2014-01-01

Human papillomavirus (HPV) is one of the most widely publicized and researched pathogenic DNA viruses. For decades, HPV research has focused on transforming viral activities in cervical cancer. During the past 15 years, however, HPV has also emerged as a major etiological agent in cancers of the head and neck, in particular squamous cell carcinoma. Even with significant strides achieved towards the screening and treatment of cervical cancer, and preventive vaccines, cervical cancer remains the leading cause of cancer-associated deaths for women in developing countries. Furthermore, routine screens are not available for those at risk of head and neck cancer. The current expectation is that HPV vaccination will prevent not only cervical, but also head and neck cancers. In order to determine if previous cervical cancer models for HPV infection and transformation are directly applicable to head and neck cancer, clinical and molecular disease aspects must be carefully compared. In this review, we briefly discuss the cervical and head and neck cancer literature to highlight clinical and genomic commonalities. Differences in prognosis, staging and treatment, as well as comparisons of mutational profiles, viral integration patterns, and alterations in gene expression will be addressed

Estimating Contact Exposure in Football Using the Head Impact Exposure Estimate.

Science.gov (United States)

Kerr, Zachary Y; Littleton, Ashley C; Cox, Leah M; DeFreese, J D; Varangis, Eleanna; Lynall, Robert C; Schmidt, Julianne D; Marshall, Stephen W; Guskiewicz, Kevin M

2015-07-15

Over the past decade, there has been significant debate regarding the effect of cumulative subconcussive head impacts on short and long-term neurological impairment. This debate remains unresolved, because valid epidemiological estimates of athletes' total contact exposure are lacking. We present a measure to estimate the total hours of contact exposure in football over the majority of an athlete's lifespan. Through a structured oral interview, former football players provided information related to primary position played and participation in games and practice contacts during the pre-season, regular season, and post-season of each year of their high school, college, and professional football careers. Spring football for college was also included. We calculated contact exposure estimates for 64 former football players (n = 32 college football only, n = 32 professional and college football). The head impact exposure estimate (HIEE) discriminated between individuals who stopped after college football, and individuals who played professional football (p < 0.001). The HIEE measure was independent of concussion history (p = 0.82). Estimating total hours of contact exposure may allow for the detection of differences between individuals with variation in subconcussive impacts, regardless of concussion history. This measure is valuable for the surveillance of subconcussive impacts and their associated potential negative effects.

Relative brain displacement and deformation during constrained mild frontal head impact.

Science.gov (United States)

Feng, Y; Abney, T M; Okamoto, R J; Pless, R B; Genin, G M; Bayly, P V

2010-12-06

This study describes the measurement of fields of relative displacement between the brain and the skull in vivo by tagged magnetic resonance imaging and digital image analysis. Motion of the brain relative to the skull occurs during normal activity, but if the head undergoes high accelerations, the resulting large and rapid deformation of neuronal and axonal tissue can lead to long-term disability or death. Mathematical modelling and computer simulation of acceleration-induced traumatic brain injury promise to illuminate the mechanisms of axonal and neuronal pathology, but numerical studies require knowledge of boundary conditions at the brain-skull interface, material properties and experimental data for validation. The current study provides a dense set of displacement measurements in the human brain during mild frontal skull impact constrained to the sagittal plane. Although head motion is dominated by translation, these data show that the brain rotates relative to the skull. For these mild events, characterized by linear decelerations near 1.5g (g = 9.81 m s⁻²) and angular accelerations of 120-140 rad s⁻², relative brain-skull displacements of 2-3 mm are typical; regions of smaller displacements reflect the tethering effects of brain-skull connections. Strain fields exhibit significant areas with maximal principal strains of 5 per cent or greater. These displacement and strain fields illuminate the skull-brain boundary conditions, and can be used to validate simulations of brain biomechanics.

Similar head impact acceleration measured using instrumented ear patches in a junior rugby union team during matches in comparison with other sports.

Science.gov (United States)

King, Doug A; Hume, Patria A; Gissane, Conor; Clark, Trevor N

2016-07-01

OBJECTIVE Direct impact with the head and the inertial loading of the head have been postulated as major mechanisms of head-related injuries, such as concussion. METHODS This descriptive observational study was conducted to quantify the head impact acceleration characteristics in under-9-year-old junior rugby union players in New Zealand. The impact magnitude, frequency, and location were collected with a wireless head impact sensor that was worn by 14 junior rugby players who participated in 4 matches. RESULTS A total of 721 impacts > 10g were recorded. The median (interquartile range [IQR]) number of impacts per player was 46 (IQR 37-58), resulting in 10 (IQR 4-18) impacts to the head per player per match. The median impact magnitudes recorded were 15g (IQR 12g-21g) for linear acceleration and 2296 rad/sec(2) (IQR 1352-4152 rad/sec(2)) for rotational acceleration. CONCLUSIONS There were 121 impacts (16.8%) above the rotational injury risk limit and 1 (0.1%) impact above the linear injury risk limit. The acceleration magnitude and number of head impacts in junior rugby union players were higher than those previously reported in similar age-group sports participants. The median linear acceleration for the under-9-year-old rugby players were similar to 7- to 8-year-old American football players, but lower than 9- to 12-year-old youth American football players. The median rotational accelerations measured were higher than the median and 95th percentiles in youth, high school, and collegiate American football players.

The influence of headform orientation and flooring systems on impact dynamics during simulated fall-related head impacts.

Science.gov (United States)

Wright, Alexander D; Laing, Andrew C

2012-10-01

Novel compliant flooring systems are a promising approach for reducing fall-related injuries in seniors, as they may provide up to 50% attenuation in peak force during simulated hip impacts while eliciting only minimal influences on balance. This study aimed to determine the protective capacity of novel compliant floors during simulated 'high severity' head impacts compared to common flooring systems. A headform was impacted onto a common Commercial-Carpet at 1.5, 2.5, and 3.5 m/s in front, back, and side orientations using a mechanical drop tower. Peak impact force applied to the headform (F(max)), peak linear acceleration of the headform (g(max)) and Head Injury Criterion (HIC) were determined. For the 3.5 m/s trials, backwards-oriented impacts were associated with the highest F(max) and HIC values (pfloors (Resilient Rubber, Residential-Loop Carpet, Berber Carpet) and six novel compliant floors at each impact velocity. ANOVAs indicated that flooring type was associated with all parameters at each impact velocity (pfloors (pfloors can substantially reduce the forces and accelerations applied to a headform compared to common floors including carpet and resilient rubber. In combination with reports of minimal balance impairments, these findings support the promise of novel compliant floors as a biomechanically effective strategy for reducing fall-related injuries including traumatic brain injuries and skull fractures. Copyright © 2011 IPEM. Published by Elsevier Ltd. All rights reserved.

Instrumented mouthguard acceleration analyses for head impacts in amateur rugby union players over a season of matches.

Science.gov (United States)

King, Doug; Hume, Patria A; Brughelli, Matt; Gissane, Conor

2015-03-01

Direct impacts with the head (linear acceleration or pressure) and inertial loading of the head (rotational acceleration or strain) have been postulated as the 2 major mechanisms of head-related injuries such as concussion. Although data are accumulating for soccer and American football, there are no published data for nonhelmeted collision sports such as rugby union. To quantify head impacts via instrumented mouthguard acceleration analyses for rugby union players over a season of matches. Descriptive epidemiology study. Data on impact magnitude and frequency were collected with molded instrumented mouthguards worn by 38 premier amateur senior rugby players participating in the 2013 domestic season of matches. A total of 20,687 impacts >10g (range, 10.0-164.9g) were recorded over the duration of the study. The mean ± SD number of impacts per player over the duration of the season of matches was 564 ± 618, resulting in a mean ± SD of 95 ± 133 impacts to the head per player, per match over the duration of the season of matches. The impact magnitudes for linear accelerations were skewed to the lower values (Sp = 3.7 ± 0.02; P rugby union players over a season of matches, measured via instrumented mouthguard accelerations, were higher than for most sports previously reported. Mean linear acceleration measured over a season of matches was similar to the mean linear accelerations previously reported for youth, high school, and collegiate American football players but lower than that for female youth soccer players. Mean rotational acceleration measured over a season of matches was similar to mean rotational accelerations for youth, high school, and collegiate American football players but less than those for female youth soccer players, concussed American collegiate players, collegiate American football players, and professional American football players. © 2014 The Author(s).

Brain tissue strains vary with head impact location: A possible explanation for increased concussion risk in struck versus striking football players.

Science.gov (United States)

Elkin, Benjamin S; Gabler, Lee F; Panzer, Matthew B; Siegmund, Gunter P

2018-03-29

On-field football helmet impacts over a large range of severities have caused concussions in some players but not in other players. One possible explanation for this variability is the struck player's helmet impact location. We examined the effect of impact location on regional brain tissue strain when input energy was held constant. Laboratory impacts were performed at 12 locations distributed over the helmet and the resulting head kinematics were simulated in two finite element models of the brain: the Simulated Injury Monitor and the Global Human Body Model Consortium brain model. Peak kinematics, injury metrics and brain strain varied significantly with impact location. Differences in impact location explained 33 to 37% of the total variance in brain strain for the whole brain and cerebrum, considerably more than the variance explained by impact location for the peak resultant head kinematics (8 to 23%) and slightly more than half of the variance explained by the difference in closing speed (57 to 61%). Both finite element models generated similar strain results, with minor variations for impacts that generated multi-axial rotations, larger variations in brainstem strains for some impact locations and a small bias for the cerebellum. Based on this experimental and computational simulation study, impact location on the football helmet has a large effect on regional brain tissue strain. We also found that the lowest strains consistently occurred in impacts to the crown and forehead, helmet locations commonly associated with the striking player. Copyright © 2018 Elsevier Ltd. All rights reserved.

Human Papilloma Virus Associated Squamous Cell Carcinoma of the Head and Neck

OpenAIRE

Ajila, Vidya; Shetty, Harish; Babu, Subhas; Shetty, Veena; Hegde, Shruthi

2015-01-01

Oral cancer is one of the commonest causes for mortality and morbidity with squamous cell carcinoma being the sixth most frequent malignant tumour worldwide. In addition to tobacco and alcohol, human papilloma virus (HPV) is associated with a proportion of head and neck cancers. As in cervical cancers, HPV types 16 and 18 are the cause of malignant transformation. HPV-positive cancers of head and neck have unique characteristics such as occurrence in a younger age group, distinct clinical and...

Changes in parents' spanking and reading as mechanisms for Head Start impacts on children.

Science.gov (United States)

Gershoff, Elizabeth T; Ansari, Arya; Purtell, Kelly M; Sexton, Holly R

2016-06-01

This study examined whether Head Start, the nation's main two-generation program for low-income families, benefits children in part through positive changes in parents' use of spanking and reading to children. Data were drawn from the 3-year-old cohort of the national evaluation of the Head Start program known as the Head Start Impact Study (N = 2,063). Results indicated that Head Start had small, indirect effects on children's spelling ability at Age 4 and their aggression at Age 4 through an increase in parents' reading to their children. Taken together, the results suggest that parents play a role in sustaining positive benefits of the Head Start program for children's behavior and literacy skills, one that could be enhanced with a greater emphasis on parent involvement and education. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Integration of visual and non-visual self-motion cues during voluntary head movements in the human brain.

Science.gov (United States)

Schindler, Andreas; Bartels, Andreas

2018-05-15

Our phenomenological experience of the stable world is maintained by continuous integration of visual self-motion with extra-retinal signals. However, due to conventional constraints of fMRI acquisition in humans, neural responses to visuo-vestibular integration have only been studied using artificial stimuli, in the absence of voluntary head-motion. We here circumvented these limitations and let participants to move their heads during scanning. The slow dynamics of the BOLD signal allowed us to acquire neural signal related to head motion after the observer's head was stabilized by inflatable aircushions. Visual stimuli were presented on head-fixed display goggles and updated in real time as a function of head-motion that was tracked using an external camera. Two conditions simulated forward translation of the participant. During physical head rotation, the congruent condition simulated a stable world, whereas the incongruent condition added arbitrary lateral motion. Importantly, both conditions were precisely matched in visual properties and head-rotation. By comparing congruent with incongruent conditions we found evidence consistent with the multi-modal integration of visual cues with head motion into a coherent "stable world" percept in the parietal operculum and in an anterior part of parieto-insular cortex (aPIC). In the visual motion network, human regions MST, a dorsal part of VIP, the cingulate sulcus visual area (CSv) and a region in precuneus (Pc) showed differential responses to the same contrast. The results demonstrate for the first time neural multimodal interactions between precisely matched congruent versus incongruent visual and non-visual cues during physical head-movement in the human brain. The methodological approach opens the path to a new class of fMRI studies with unprecedented temporal and spatial control over visuo-vestibular stimulation. Copyright © 2018 Elsevier Inc. All rights reserved.

Web-based visualisation of head pose and facial expressions changes: monitoring human activity using depth data

OpenAIRE

Kalliatakis, Grigorios; Vidakis, Nikolaos; Triantafyllidis, Georgios

2017-01-01

Despite significant recent advances in the field of head pose estimation and facial expression recognition, raising the cognitive level when analysing human activity presents serious challenges to current concepts. Motivated by the need of generating comprehensible visual representations from different sets of data, we introduce a system capable of monitoring human activity through head pose and facial expression changes, utilising an affordable 3D sensing technology (Microsoft Kinect sensor)...

Subchondral bone density distribution in the human femoral head

Energy Technology Data Exchange (ETDEWEB)

Wright, David A.; Meguid, Michael; Lubovsky, Omri; Whyne, Cari M. [Sunnybrook Research Institute, Orthopaedic Biomechanics Laboratory, Toronto, Ontario (Canada)

2012-06-15

This study aims to quantitatively characterize the distribution of subchondral bone density across the human femoral head using a computed tomography derived measurement of bone density and a common reference coordinate system. Femoral head surfaces were created bilaterally for 30 patients (14 males, 16 females, mean age 67.2 years) through semi-automatic segmentation of reconstructed CT data and used to map bone density, by shrinking them into the subchondral bone and averaging the greyscale values (linearly related to bone density) within 5 mm of the articular surface. Density maps were then oriented with the center of the head at the origin, the femoral mechanical axis (FMA) aligned with the vertical, and the posterior condylar axis (PCA) aligned with the horizontal. Twelve regions were created by dividing the density maps into three concentric rings at increments of 30 from the horizontal, then splitting into four quadrants along the anterior-posterior and medial-lateral axes. Mean values for each region were compared using repeated measures ANOVA and a Bonferroni post hoc test, and side-to-side correlations were analyzed using a Pearson's correlation. The regions representing the medial side of the femoral head's superior portion were found to have significantly higher densities compared to other regions (p < 0.05). Significant side-to-side correlations were found for all regions (r {sup 2} = 0.81 to r {sup 2} = 0.16), with strong correlations for the highest density regions. Side-to-side differences in measured bone density were seen for two regions in the anterio-lateral portion of the femoral head (p < 0.05). The high correlation found between the left and right sides indicates that this tool may be useful for understanding 'normal' density patterns in hips affected by unilateral pathologies such as avascular necrosis, fracture, developmental dysplasia of the hip, Perthes disease, and slipped capital femoral head epiphysis. (orig.)

Acoustic pressure waves induced in human heads by RF pulses from high-field MRI scanners.

Science.gov (United States)

Lin, James C; Wang, Zhangwei

2010-04-01

The current evolution toward greater image resolution from magnetic resonance image (MRI) scanners has prompted the exploration of higher strength magnetic fields and use of higher levels of radio frequencies (RFs). Auditory perception of RF pulses by humans has been reported during MRI with head coils. It has shown that the mechanism of interaction for the auditory effect is caused by an RF pulse-induced thermoelastic pressure wave inside the head. We report a computational study of the intensity and frequency of thermoelastic pressure waves generated by RF pulses in the human head inside high-field MRI and clinical scanners. The U.S. Food and Drug Administration (U.S. FDA) guides limit the local specific absorption rate (SAR) in the body-including the head-to 8 W kg(-1). We present results as functions of SAR and show that for a given SAR the peak acoustic pressures generated in the anatomic head model were essentially the same at 64, 300, and 400 MHz (1.5, 7.0, and 9.4 T). Pressures generated in the anatomic head are comparable to the threshold pressure of 20 mPa for sound perception by humans at the cochlea for 4 W kg(-1). Moreover, results indicate that the peak acoustic pressure in the brain is only 2 to 3 times the auditory threshold at the U.S. FDA guideline of 8 W kg(-1). Even at a high SAR of 20 W kg(-1), where the acoustic pressure in the brain could be more than 7 times the auditory threshold, the sound pressure levels would not be more than 17 db above threshold of perception at the cochlea.

Role of awareness in head-neck acceleration in low velocity rear-end impacts.

Science.gov (United States)

Kumar, S; Narayan, Y; Amell, T

2000-03-01

Fourteen normal healthy seated and restrained young adults were delivered rear-end impacts of four intensities of acceleration. The chair was delivered a regulated and controlled pneumatic blow using a 30 cm cylinder to cause an acceleration of 0.5, 0.9, 1.1 and 1.4g. The accelerated chair was stopped suddenly by impacting the stopper at the other end of the 2 m long friction reduced track. In one set of trials, subjects were informed about the impending impact and in the other they were blindfolded and provided with loud auditory input to eliminate cues of the impact. The accelerations of the chair, shoulder and head of the participating subjects were measured triaxially and compared between levels of acceleration and expectation. The multiple analyses of variance revealed that the peak acceleration was significantly affected by the gender (P < 0.01), intensity of impact (P < 0.001), and expectation (P < 0.0001). The accelerations were significantly different in different axes (P < 0.001). A significant two-way interaction between acceleration and expectation (P < 0.03), and expectation and axes of acceleration (P < 0.02) would imply that awareness of the impending impact serves to significantly reduce the level of accelerations of head and neck.

Elemental Water Impact Test: Phase 3 Plunge Depth of a 36-Inch Aluminum Tank Head

Science.gov (United States)

Vassilakos, Gregory J.

2014-01-01

Spacecraft are being designed based on LS-DYNA water landing simulations. The Elemental Water Impact Test (EWIT) series was undertaken to assess the accuracy of LS-DYNA water impact simulations. Phase 3 featured a composite tank head that was tested at a range of heights to verify the ability to predict structural failure of composites. To support planning for Phase 3, a test series was conducted with an aluminum tank head dropped from heights of 2, 6, 10, and 12 feet to verify that the test article would not impact the bottom of the test pool. This report focuses on the comparisons of the measured plunge depths to LS-DYNA predictions. The results for the tank head model demonstrated the following. 1. LS-DYNA provides accurate predictions for peak accelerations. 2. LS-DYNA consistently under-predicts plunge depth. An allowance of at least 20% should be added to the LS-DYNA predictions. 3. The LS-DYNA predictions for plunge depth are relatively insensitive to the fluid-structure coupling stiffness.

The effect of motorcycle helmet fit on estimating head impact kinematics from residual liner crush.

Science.gov (United States)

Bonin, Stephanie J; Gardiner, John C; Onar-Thomas, Arzu; Asfour, Shihab S; Siegmund, Gunter P

2017-09-01

Proper helmet fit is important for optimizing head protection during an impact, yet many motorcyclists wear helmets that do not properly fit their heads. The goals of this study are i) to quantify how a mismatch in headform size and motorcycle helmet size affects headform peak acceleration and head injury criteria (HIC), and ii) to determine if peak acceleration, HIC, and impact speed can be estimated from the foam liner's maximum residual crush depth or residual crush volume. Shorty-style helmets (4 sizes of a single model) were tested on instrumented headforms (4 sizes) during linear impacts between 2.0 and 10.5m/s to the forehead region. Helmets were CT scanned to quantify residual crush depth and volume. Separate linear regression models were used to quantify how the response variables (peak acceleration (g), HIC, and impact speed (m/s)) were related to the predictor variables (maximum crush depth (mm), crush volume (cm 3 ), and the difference in circumference between the helmet and headform (cm)). Overall, we found that increasingly oversized helmets reduced peak headform acceleration and HIC for a given impact speed for maximum residual crush depths less than 7.9mm and residual crush volume less than 40cm 3 . Below these levels of residual crush, we found that peak headform acceleration, HIC, and impact speed can be estimated from a helmet's residual crush. Above these crush thresholds, large variations in headform kinematics are present, possibly related to densification of the foam liner during the impact. Copyright © 2017 Elsevier Ltd. All rights reserved.

Human Papilloma Virus in Head and Neck Squamous Cell Cancer

Science.gov (United States)

Asvadi Kermani, I; Seifi, SH; Dolatkhah, R; Sakhinia, E; Dastgiri, S; Ebrahimi, A; Lotfy, A; Esmaeili, HA; G, Mohammadi; M, Naderpour; SH, Hajalipour; Haggi A, Asghari; M, Nadri

2012-01-01

Background Epidemiologic and molecular evidences have established a strong link between high risk types of Human Papilloma Virus and a subgroup of Head and Neck Squamous Cell Carcinomas (HNSCC). We evaluated the frequency of HPV positivity in HNSCC and its relationship to demographic and some risk factor variables in an open case- control study. Methods Fourteen recently diagnosed patients with squamous cell cancer of oropharynx, hypopharynx and larynx aged 18-50 years were examined from 2008-2010 in Tabriz, Iran. HPV DNA was extracted from paraffin-embedded blocks of each patient's sample for PCR evaluation. Saliva samples of 94 control cancer-free subjects were collected for DNA analysis. Multivariable logistic regression method was used to calculate odds ratio for case-control comparisons. Results High risk HPV was detected in 6(42.8%) patients, and 6(5.3%) control subjects which was statistically significant (p<0.0001). HPV-18 was the most frequent type both in the cases and controls. HPV-16 DNA was detected in two patients of the case group, but it was not detected in any of the controls. The relation between demographic and risk factor variables was not statistically significant. Conclusion HPV infection has a significant impact on HNSCC. Despite HPV-16 stronger impact, HPV-18 is more likely to cause malignant degeneration in such cancers amongst some communities. It is vital to introduce and conduct immunization schedules in health care systems to protect communities to some extent. PMID:25780535

A Study Of EMR And SAR Distribution In Human Head Phantom ...

African Journals Online (AJOL)

power of 0.32W for both simulations were well below the limit of 1.6 W/kg of ICNIRP standard and FCC/IEEE standard of 2W/kg. Keywords: Electromagnetic radiation (EMR), Specific Absorption Rate (SAR), Electromagnetic simulation software (FEKO emss), Radio frequency field, human head, mobile phone, mobile phone ...

Frequency of head-impact-related outcomes by position in NCAA division I collegiate football players.

Science.gov (United States)

Baugh, Christine M; Kiernan, Patrick T; Kroshus, Emily; Daneshvar, Daniel H; Montenigro, Philip H; McKee, Ann C; Stern, Robert A

2015-03-01

Concussions and subconcussive impacts sustained in American football have been associated with short- and long-term neurological impairment, but differences in head impact outcomes across playing positions are not well understood. The American Medical Society for Sports Medicine has identified playing position as a key risk factor for concussion in football and one for which additional research is needed. This study examined variation in head impact outcomes across primary football playing positions in a group of 730 National Collegiate Athletic Association Division I Football Championship Series athletes, using a self-report questionnaire. Although there were no significant differences between position groups in the number of diagnosed concussions during the 2012 football season, there were significant differences between groups in undiagnosed concussions (p=0.008) and "dings" (pfootball season, with offensive linemen reporting significantly more symptoms compared to most other groups. There were also positional differences in frequency of returning to play while symptomatic (p<0.001) and frequency of participating in full-contact practice (p<0.001). Offensive linemen reported having returned to play while experiencing symptoms more frequently and participating in more full-contact practices than other groups. These findings suggest that offensive linemen, a position group that experiences frequent, but low-magnitude, head impacts, develop more postimpact symptoms than other playing positions, but do not report these symptoms as a concussion.

The ultimate intrinsic signal-to-noise ratio of loop- and dipole-like current patterns in a realistic human head model.

Science.gov (United States)

Pfrommer, Andreas; Henning, Anke

2018-03-13

The ultimate intrinsic signal-to-noise ratio (UISNR) represents an upper bound for the achievable SNR of any receive coil. To reach this threshold a complete basis set of equivalent surface currents is required. This study systematically investigated to what extent either loop- or dipole-like current patterns are able to reach the UISNR threshold in a realistic human head model between 1.5 T and 11.7 T. Based on this analysis, we derived guidelines for coil designers to choose the best array element at a given field strength. Moreover, we present ideal current patterns yielding the UISNR in a realistic body model. We distributed generic current patterns on a cylindrical and helmet-shaped surface around a realistic human head model. We excited electromagnetic fields in the human head by using eigenfunctions of the spherical and cylindrical Helmholtz operator. The electromagnetic field problem was solved by a fast volume integral equation solver. At 7 T and above, adding curl-free current patterns to divergence-free current patterns substantially increased the SNR in the human head (locally >20%). This was true for the helmet-shaped and the cylindrical surface. On the cylindrical surface, dipole-like current patterns had high SNR performance in central regions at ultra-high field strength. The UISNR increased superlinearly with B0 in most parts of the cerebrum but only sublinearly in the periphery of the human head. The combination of loop and dipole elements could enhance the SNR performance in the human head at ultra-high field strength. © 2018 International Society for Magnetic Resonance in Medicine.

Effectiveness of isopropyl myristate/cyclomethicone D5 solution of removing cuticular hydrocarbons from human head lice (Pediculus humanus capitis

Directory of Open Access Journals (Sweden)

Barnett Eric

2012-09-01

Full Text Available Abstract Background In the treatment of human head lice infestation, healthcare providers are increasingly concerned about lice becoming resistant to existing pesticide treatments. Traditional pesticides, used to control these pests, have a neurological mechanism of action. This publication describes a topical solution with a non-traditional mechanism of action, based on physical disruption of the wax layer that covers the cuticle of the louse exoskeleton. This topical solution has been shown clinically to cure 82% of patients with only a 10-minute treatment time, repeated once after 7 days. All insects, including human head lice, have a wax-covered exoskeleton. This wax, composed of hydrocarbons, provides the insect with protection against water loss and is therefore critical to its survival. When the protective wax is disrupted, water loss becomes uncontrollable and irreversible, leading to dehydration and death. A specific pattern of hydrocarbons has been found in all of the head louse cuticular wax studied. Iso-octane effectively removes these hydrocarbons from human head lice’s cuticular wax. Methods A method of head louse cuticle wax extraction and analysis by gas chromatography was developed. Human head lice (Pediculus humanus capitis were collected from infested patients and subjected to any of three extraction solvents comprising either the test product or one of two solvents introduced as controls. A gas chromatograph equipped with a flame ionization detector (GC/FID was used to determine the presence of hydrocarbons in the three head lice extracts. Results In the study reported herein, the test product isopropyl myristate/cyclomethicone D5 (IPM/D5 was shown to perform comparably with iso-octane, effectively extracting the target hydrocarbons from the cuticular wax that coats the human head louse exoskeleton. Conclusions Disruption of the integrity of the insect cuticle by removal of specific hydrocarbons found in the cuticular wax

Neuropsychological development in preschool children born with asymmetrical intrauterine growth restriction and impact of postnatal head growth.

Science.gov (United States)

Klaric, Andrea Simić; Galić, Slavka; Kolundzić, Zdravko; Bosnjak, Vlatka Mejaski

2013-07-01

Neuropsychological development and the impact of postnatal head growth were studied in preschool children with asymmetrical intrauterine growth restriction. Examinees born at term with a birth weight below the 10th percentile were matched to the control group according to chronological and gestational age, gender, and maternal education. Fifty children were in each group, with a mean age of 6 years, 4 months. The Touwen neurological examination, the Čuturić developmental test, an imitative hand positions test, and a visual attention test were performed. There were significant differences (Pmotor variables, the developmental quotient, and the imitative hand positions test. Fine motor skills had the most discriminative power. Relative growth of the head in relation to weight gain was positively correlated to neurocognitive outcome. Intrauterine growth-restricted children with a current head circumference ≤10th percentile had poorer outcomes. Conclusively, intrauterine growth restriction has a negative impact on neurocognitive development. Slow postnatal head growth is correlated with a poorer neuropsychological outcome.

Eyewear Computing – Augmenting the Human with Head-mounted Wearable Assistants (Dagstuhl Seminar 16042)

OpenAIRE

Bulling, Andreas; Cakmakci, Ozan; Kunze, Kai; Rehg, James M.

2016-01-01

The seminar was composed of workshops and tutorials on head-mounted eye tracking, egocentric vision, optics, and head-mounted displays. The seminar welcomed 30 academic and industry researchers from Europe, the US, and Asia with a diverse background, including wearable and ubiquitous computing, computer vision, developmental psychology, optics, and human-computer interaction. In contrast to several previous Dagstuhl seminars, we used an ignite talk format to reduce the time of talks to...

Head-Impact–Measurement Devices: A Systematic Review

Science.gov (United States)

O'Connor, Kathryn L.; Rowson, Steven; Duma, Stefan M.; Broglio, Steven P.

2017-01-01

Context: With an estimated 3.8 million sport- and recreation-related concussions occurring annually, targeted prevention and diagnostic methods are needed. Biomechanical analysis of head impacts may provide quantitative information that can inform both prevention and diagnostic strategies. Objective: To assess available head-impact devices and their clinical utility. Data Sources: We performed a systematic search of the electronic database PubMed for peer-reviewed publications, using the following phrases: accelerometer and concussion, head impact telemetry, head impacts and concussion and sensor, head impacts and sensor, impact sensor and concussion, linear acceleration and concussion, rotational acceleration and concussion, and xpatch concussion. In addition to the literature review, a Google search for head impact monitor and concussion monitor yielded 15 more devices. Study Selection: Included studies were performed in vivo, used commercially available devices, and focused on sport-related concussion. Data Extraction: One author reviewed the title and abstract of each study for inclusion and exclusion criteria and then reviewed each full-text article to confirm inclusion criteria. Controversial articles were reviewed by all authors to reach consensus. Data Synthesis: In total, 61 peer-reviewed articles involving 4 head-impact devices were included. Participants in boxing, football, ice hockey, soccer, or snow sports ranged in age from 6 to 24 years; 18% (n = 11) of the studies included female athletes. The Head Impact Telemetry System was the most widely used device (n = 53). Fourteen additional commercially available devices were presented. Conclusions: Measurements collected by impact monitors provided real-time data to estimate player exposure but did not have the requisite sensitivity to concussion. Proper interpretation of previously reported head-impact kinematics across age, sport, and position may inform future research and enable staff clinicians

The impact of virus in N3 node dissection for head and neck cancer.

Science.gov (United States)

Armas, Gian Luca; Su, Chih-Ying; Huang, Chao-Cheng; Fang, Fu-Min; Chen, Ching-Mei; Chien, Chih-Yen

2008-11-01

This study is to determine the impact of virus in surgical outcomes among patients of head and neck cancer with N3 lymph node metastasis. A retrospective analysis was conducted for 32 patients with operable N3 neck metastasis undergoing surgical treatment between January 1987 and October 2006. The nuclei of the tumor cells were investigated for the presence of human papillomavirus (HPV) and Epstein-Barr virus (EBV) DNAs and were taken into account as the variable for survival analysis. The primary sites were oropharynx in 11 patients, tongue in 3, buccal mucosa in 1, hypopharynx in 8 and unknown primary in 9. The five-year cumulative overall survival rate was 40.7% and 5-year cumulative regional control rate was 55.8%. The 5-year cumulative overall survival rate of patients with unknown primary site (72.9%) and HPV or EBV positive in the tumor (77.8%) were significantly higher than those patients with known primary site (31.3%) and HPV or EBV negative in the tumor (27.4%), respectively (P = 0.0335 and P = 0.0348, log rank test). In conclusion, surgery with adjuvant therapy offers reasonable outcomes for operable N3 node in head and neck cancer in our cohort. In addition, patients with HPV or EBV positive in the tumor have a better survival.

Relationship Between Neck Strength, Anthropometric Parameters, and Gender with Head Motion under Impact Acceleration

National Research Council Canada - National Science Library

Morris, Charles

1996-01-01

.... Since women tend to have less upper-body strength than men, it was hypothesized that they may not be able to brace their heads as effectively against the loads which occur during impact and escape...

Kinematics of the human mandible for different head postures.

Science.gov (United States)

Visscher, C M; Huddleston Slater, J J; Lobbezoo, F; Naeije, M

2000-04-01

The influence of head posture on movement paths of the incisal point (IP) and of the mandibular condyles during free open-close movements was studied. Ten persons, without craniomandibular or cervical spine disorders, participated in the study. Open close mandibular movements were recorded with the head in five postures, viz., natural head posture, forward head posture, military posture, and lateroflexion to the right and to the left side, using the Oral Kinesiologic Analysis System (OKAS-3D). This study showed that in a military head posture, the opening movement path of the incisal point is shifted anteriorly relative to the path in a natural head posture. In a forward head posture, the movement path is shifted posteriorly whereas during lateroflexion, it deviates to the side the head has moved to. Moreover, the intra-articular distance in the temporomandibular joint during closing is smaller with the head in military posture and greater in forward head posture, as compared to the natural head posture. During lateroflexion, the intra-articular distance on the ipsilateral side is smaller. The influence of head posture upon the kinematics of the mandible is probably a manifestation of differences in mandibular loading in the different head postures.

Analysis of SAR distribution in human head of antenna used in wireless power transform based on magnetic resonance.

Science.gov (United States)

Gong, Feixiang; Wei, Zhiqiang; Cong, Yanping; Chi, Haokun; Yin, Bo; Sun, Mingui

2017-07-20

In this paper, a novel wireless power transfer antenna system was designed for human head implantable devices. The antenna system used the structure of three plates and four coils and operated at low frequencies to transfer power via near field. In order to verify the electromagnetic radiation safety on the human head, the electromagnetic intensity and specific absorption rate (SAR) were studied by finite-difference-time-domain (FDTD) method. A three-layer model of human head including skin, bone and brain tissues was constructed. The transmitting and receiving antenna were set outside and inside the model. The local and average SAR were simulated at the resonance frequency of 18.67 MHz in two situations, in one scenario both transmitting and receiving coil worked, while in the other scenario only the transmitting coil worked. The results showed that the maximum of 10 g SAR average value of human thoracic were 0.142 W/kg and 0.148 W/kg, respectively, both were lower than the international safety standards for human body of the ICNIRP and FCC, which verified the safety of the human body in wireless power transmission based on magnetic coupling resonance.

Heads of household programme in Argentina: a human rights-based policy?

Science.gov (United States)

Colina, Jorge; Giordano, Osvaldo; Torres, Alejandra; Cárdenas, Marcelo

2009-01-01

This study analyses the consultative councils (CC) of the Argentinian conditional cash transfer heads of household programme as an institutional innovation directed to put into practice some of the principles of the human rights' approach for eradicating poverty. Since the main responsibilities assigned to the CCs coincided with some of the main principles of the human rights' approach, the research is focused on how CCs responded in practice. Using a case study methodology we show that even when, in theory, the CCs incorporate some of the principles of the human rights' approach to the programme, they deviated from this purpose due to a persistent phenomenon in the social policy arena in developing countries: political clientelism. Policy recommendations are formulated in order to deal with clientelism in the framework of the human rights' approach.

Impact of HPV infection on the development of head and neck cancer

Science.gov (United States)

Betiol, J.; Villa, L.L.; Sichero, L.

2013-01-01

Human papillomavirus (HPV)-related head and neck squamous cell carcinoma (HNSCC) is considered to be a distinct clinical entity with better prognosis than the classical tobacco- and alcohol-associated tumors. The increasing incidence of this neoplasia during the last decades highlights the need to better understand the role of HPV in the development of these cancers. Although the proportion of HNSCC attributed to HPV varies considerably according to anatomical site, overall approximately 25% of all HNSCC are HPV-DNA positive, and HPV-16 is by far the most prevalent type. In this review we discuss the existing evidence for a causal association between HPV infection and HNSCC at diverse anatomical head and neck subsites. PMID:23532264

Vertical eye position-dependence of the human vestibuloocular reflex during passive and active yaw head rotations.

Science.gov (United States)

Thurtell, M J; Black, R A; Halmagyi, G M; Curthoys, I S; Aw, S T

1999-05-01

Vertical eye position-dependence of the human vestibuloocular reflex during passive and active yaw head rotations. The effect of vertical eye-in-head position on the compensatory eye rotation response to passive and active high acceleration yaw head rotations was examined in eight normal human subjects. The stimuli consisted of brief, low amplitude (15-25 degrees ), high acceleration (4,000-6,000 degrees /s2) yaw head rotations with respect to the trunk (peak velocity was 150-350 degrees /s). Eye and head rotations were recorded in three-dimensional space using the magnetic search coil technique. The input-output kinematics of the three-dimensional vestibuloocular reflex (VOR) were assessed by finding the difference between the inverted eye velocity vector and the head velocity vector (both referenced to a head-fixed coordinate system) as a time series. During passive head impulses, the head and eye velocity axes aligned well with each other for the first 47 ms after the onset of the stimulus, regardless of vertical eye-in-head position. After the initial 47-ms period, the degree of alignment of the eye and head velocity axes was modulated by vertical eye-in-head position. When fixation was on a target 20 degrees up, the eye and head velocity axes remained well aligned with each other. However, when fixation was on targets at 0 and 20 degrees down, the eye velocity axis tilted forward relative to the head velocity axis. During active head impulses, the axis tilt became apparent within 5 ms of the onset of the stimulus. When fixation was on a target at 0 degrees, the velocity axes remained well aligned with each other. When fixation was on a target 20 degrees up, the eye velocity axis tilted backward, when fixation was on a target 20 degrees down, the eye velocity axis tilted forward. The findings show that the VOR compensates very well for head motion in the early part of the response to unpredictable high acceleration stimuli-the eye position- dependence of the

Human papilloma virus infection in head and neck cancer.

Science.gov (United States)

Tribius, Silke; Hoffmann, Markus

2013-03-01

The causal link between cervical cancer and human papilloma virus (HPV) is well known. It is now becoming clear that some types of squamous-cell carcinoma of the head and neck, particularly oropharyngeal carcinoma (OPC), are also linked to HPV infection. The development of vaccines against certain HPV genotypes has changed the management strategy for HPV-associated diseases of the uterine cervix. An analogous approach is now being considered for the prevention of HPV-associated diseases of the head and neck. We review pertinent articles retrieved by a selective search of the literature for phase II and III trials providing evidence about a possible effect of HPV status on the survival rates of patients with OPC. Seven trials fulfilled our search criteria: four phase III trials with retrospective HPV analysis and three phase II trials with retrospective and prospective HPV analysis. Patients with HPV-positive OPC survive significantly longer than those with HPV-negative OPC. Tobacco smoking has been identified as a negative prognostic factor in patients with either HPV-negative or HPV-positive disease. The established treatment strategy for OPC in patients with and without the traditional risk factors (tobacco and alcohol consumption) is now being reconsidered in the light of what we have learned about the role of HPV infection. Ongoing and projected clinical trials with risk-factor stratification may soon lead to changes in treatment. Further study is needed to answer the question whether HPV infection in the head and neck region is carcinogenic.

Repetitive head impacts do not affect postural control following a competitive athletic season.

Science.gov (United States)

Murray, Nicholas G; Grimes, Katelyn E; Shiflett, Eric D; Munkasy, Barry A; D'Amico, Nathan R; Mormile, Megan E; Powell, Douglas W; Buckley, Thomas A

2017-10-03

Evidence suggests that Repetitive Head Impacts (RHI) directly influence the brain over the course of a single contact collision season yet do not significantly impact a player's performance on the standard clinical concussion assessment battery. The purpose of this study was to investigate changes in static postural control after a season of RHI in Division I football athletes using more sensitive measures of postural control as compared to a non-head contact sports. Fourteen Division I football players (CON) (age=20.4±1.12years) and fourteen non-contact athletes (NON) (2 male, 11 female; age=19.85±1.21years) completed a single trial of two minutes of eyes open quiet upright stance on a force platform (1000Hz) prior to athletic participation (PRE) and at the end of the athletic season (POST). All CON athletes wore helmets outfitted with Head Impact Telemetry (HIT) sensors and total number of RHI and linear accelerations forces of each RHI were recorded. Center of pressure root mean square (RMS), peak excursion velocity (PEV), and sample entropy (SampEn) in the anteroposterior (AP) and mediolateral (ML) directions were calculated. CON group experienced 649.5±496.8 mean number of impacts, 27.1±3.0 mean linear accelerations, with ≈1% of total player impacts exceeded 98g over the course of the season. There were no significant interactions for group x time RMS in the AP (p=0.434) and ML (p=0.114) directions, PEV in the AP (p=0.262) and ML (p=0.977) directions, and SampEn in the AP (p=0.499) and ML (p=0.984) directions. In addition, no significant interactions for group were observed for RMS in the AP (p=0.105) and ML (p=0.272) directions, PEV in the AP (p=0.081) and ML (p=0.143) directions, and SampEn in the AP (p=0.583) and ML (p=0.129) directions. These results suggest that over the course of a single competitive season, RHI do not negatively impact postural control even when measured with sensitive non-linear metrics. Copyright © 2017 Elsevier B.V. All rights

Estimating Contact Exposure in Football Using the Head Impact Exposure Estimate

OpenAIRE

Kerr, Zachary Y.; Littleton, Ashley C.; Cox, Leah M.; DeFreese, J.D.; Varangis, Eleanna; Lynall, Robert C.; Schmidt, Julianne D.; Marshall, Stephen W.; Guskiewicz, Kevin M.

2015-01-01

Over the past decade, there has been significant debate regarding the effect of cumulative subconcussive head impacts on short and long-term neurological impairment. This debate remains unresolved, because valid epidemiological estimates of athletes' total contact exposure are lacking. We present a measure to estimate the total hours of contact exposure in football over the majority of an athlete's lifespan. Through a structured oral interview, former football players provided information rel...

Habitat mosaics and path analysis can improve biological conservation of aquatic biodiversity in ecosystems with low-head dams.

Science.gov (United States)

Hitchman, Sean M; Mather, Martha E; Smith, Joseph M; Fencl, Jane S

2018-04-01

Conserving native biodiversity depends on restoring functional habitats in the face of human-induced disturbances. Low-head dams are a ubiquitous human impact that degrades aquatic ecosystems worldwide. To improve our understanding of how low-head dams impact habitat and associated biodiversity, our research examined complex interactions among three spheres of the total environment. i.e., how low-head dams (anthroposphere) affect aquatic habitat (hydrosphere), and native biodiversity (biosphere) in streams and rivers. Creation of lake-like habitats upstream of low-head dams is a well-documented major impact of dams. Alterations downstream of low head dams also have important consequences, but these downstream dam effects are more challenging to detect. In a multidisciplinary field study at five dammed and five undammed sites within the Neosho River basin, KS, we tested hypotheses about two types of habitat sampling (transect and mosaic) and two types of statistical analyses (analysis of covariance and path analysis). We used fish as our example of biodiversity alteration. Our research provided three insights that can aid environmental professionals who seek to conserve and restore fish biodiversity in aquatic ecosystems threatened by human modifications. First, a mosaic approach identified habitat alterations below low-head dams (e.g. increased proportion of riffles) that were not detected using the more commonly-used transect sampling approach. Second, the habitat mosaic approach illustrated how low-head dams reduced natural variation in stream habitat. Third, path analysis, a statistical approach that tests indirect effects, showed how dams, habitat, and fish biodiversity interact. Specifically, path analysis revealed that low-head dams increased the proportion of riffle habitat below dams, and, as a result, indirectly increased fish species richness. Furthermore, the pool habitat that was created above low-head dams dramatically decreased fish species richness

Habitat mosaics and path analysis can improve biological conservation of aquatic biodiversity in ecosystems with low-head dams

Science.gov (United States)

Hitchman, Sean M.; Mather, Martha E.; Smith, Joseph M.; Fencl, Jane S.

2018-01-01

Conserving native biodiversity depends on restoring functional habitats in the face of human-induced disturbances. Low-head dams are a ubiquitous human impact that degrades aquatic ecosystems worldwide. To improve our understanding of how low-head dams impact habitat and associated biodiversity, our research examined complex interactions among three spheres of the total environment. i.e., how low-head dams (anthroposphere) affect aquatic habitat (hydrosphere), and native biodiversity (biosphere) in streams and rivers. Creation of lake-like habitats upstream of low-head dams is a well-documented major impact of dams. Alterations downstream of low head dams also have important consequences, but these downstream dam effects are more challenging to detect. In a multidisciplinary field study at five dammed and five undammed sites within the Neosho River basin, KS, we tested hypotheses about two types of habitat sampling (transect and mosaic) and two types of statistical analyses (analysis of covariance and path analysis). We used fish as our example of biodiversity alteration. Our research provided three insights that can aid environmental professionals who seek to conserve and restore fish biodiversity in aquatic ecosystems threatened by human modifications. First, a mosaic approach identified habitat alterations below low-head dams (e.g. increased proportion of riffles) that were not detected using the more commonly-used transect sampling approach. Second, the habitat mosaic approach illustrated how low-head dams reduced natural variation in stream habitat. Third, path analysis, a statistical approach that tests indirect effects, showed how dams, habitat, and fish biodiversity interact. Specifically, path analysis revealed that low-head dams increased the proportion of riffle habitat below dams, and, as a result, indirectly increased fish species richness. Furthermore, the pool habitat that was created above low-head dams dramatically decreased fish species

Head injury predictors in sports trauma--a state-of-the-art review.

Science.gov (United States)

Fernandes, Fábio A O; de Sousa, Ricardo J Alves

2015-08-01

Head injuries occur in a great variety of sports. Many of these have been associated with neurological injuries, affecting the central nervous system. Some examples are motorsports, cycling, skiing, horse riding, mountaineering and most contact sports such as football, ice and field hockey, soccer, lacrosse, etc. The outcome of head impacts in these sports can be very severe. The worst-case scenarios of permanent disability or even death are possibilities. Over recent decades, many In recent decades, a great number of head injury criteria and respective thresholds have been proposed. However, the available information is much dispersed and a consensus has still not been achieved regarding the best injury criteria or even their thresholds. This review paper gives a thorough overview of the work carried out by the scientific community in the field of impact biomechanics about head injuries sustained during sports activity. The main goal is to review the head injury criteria, as well as their thresholds. Several are reviewed, from the predictors based on kinematics to the ones based on human tissue thresholds. In this work, we start to briefly introduce the head injuries and their mechanisms commonly seen as a result of head trauma in sports. Then, we present and summarize the head injury criteria and their respective thresholds. © IMechE 2015.

The science of shrinking human heads: tribal warfare and revenge among the South American Jivaro-Shuar.

Science.gov (United States)

Jandial, Rahul; Hughes, Samuel A; Aryan, Henry E; Marshall, Lawrence F; Levy, Michael L

2004-11-01

THE PRACTICE OF "head-shrinking" has been the proper domain not of Africa but rather of the denizens of South America. Specifically, in the post-Columbian period, it has been most famously the practice of a tribe of indigenous people commonly called the Jivaro or Jivaro-Shuar. The evidence suggests that the Jivaro-Shuar are merely the last group to retain a custom widespread in northwestern South America. In both ceramic and textile art of the pre-Columbian residents of Peru, the motif of trophy heads smaller than normal life-size heads commonly recurs; the motif is seen even in surviving carvings in stone and shell. Moreover, although not true shrunken heads, trophy heads found in late pre-Columbian and even post-Columbian graves of the region demonstrate techniques of display very similar to those used by the Jivaro-Shuar, at least some of which are best understood in the context of head-shrinking. Regardless, the Jivaro-Shuar and their practices provide an illustrative counterexample to popular myth regarding the culture and science of the shrinking of human heads.

From fish to modern humans--comparative anatomy, homologies and evolution of the head and neck musculature.

Science.gov (United States)

Diogo, R; Abdala, V; Lonergan, N; Wood, B A

2008-10-01

In a recent paper Diogo (2008) reported the results of the first part of an investigation of the comparative anatomy, homologies and evolution of the head and neck muscles of osteichthyans (bony fish + tetrapods). That report mainly focused on actinopterygian fish, but also compared these fish with certain non-mammalian sarcopterygians. The present paper focuses mainly on sarcopterygians, and particularly on how the head and neck muscles have evolved during the transitions from sarcopterygian fish and non-mammalian tetrapods to monotreme and therian mammals, including modern humans. The data obtained from our dissections of the head and neck muscles of representative members of sarcopterygian fish, amphibians, reptiles, monotremes and therian mammals, such as rodents, tree-shrews, colugos and primates, including modern humans, are compared with the information available in the literature. Our observations and comparisons indicate that the number of mandibular and true branchial muscles (sensu this work) present in modern humans is smaller than that found in mammals such as tree-shrews, rats and monotremes, as well as in reptiles such as lizards. Regarding the pharyngeal musculature, there is an increase in the number of muscles at the time of the evolutionary transition leading to therian mammals, but there was no significant increase during the transition leading to the emergence of higher primates and modern humans. The number of hypobranchial muscles is relatively constant within the therian mammals we examined, although in this case modern humans have more muscles than other mammals. The number of laryngeal and facial muscles in modern humans is greater than that found in most other therian taxa. Interestingly, modern humans possess peculiar laryngeal and facial muscles that are not present in the majority of the other mammalian taxa; this seems to corroborate the crucial role played by vocal communication and by facial expressions in primate and especially in

Nutrition impact symptoms and associated outcomes in post-chemoradiotherapy head and neck cancer survivors: a systematic review.

Science.gov (United States)

Crowder, Sylvia L; Douglas, Katherine G; Yanina Pepino, M; Sarma, Kalika P; Arthur, Anna E

2018-03-20

It is estimated that more than 90% of head and neck cancer (HNC) survivors who underwent chemoradiotherapy experience one or more nutrition impact symptoms (NIS) in the months or years thereafter. Despite the high prevalence, there is limited research addressing long-term impact of NIS on outcomes such as nutrition and quality of life in HNC survivors treated with chemoradiotherapy. To conduct a systematic review of the literature pertaining to the presence of nutrition impact symptoms and their associated outcomes in post-chemoradiotherapy head and neck cancer survivors. A systematic review was conducted across three databases according to PRISMA guidelines and used to identify current literature regarding NIS in HNC survivors. A keyword search was conducted in PubMed, Scopus, and Web of Science from 2007 to 2017. Studies that met all of the following criteria were included in the review: (1) studies must include human subjects with a HNC diagnosis; (2) study participants must have received chemoradiotherapy; (3) study participants must have been post-treatment for a minimum of 3 months at the time of data collection; (4) full-text articles must have appeared in peer-reviewed journals; (5) papers must have been published in English; (6) studies must be quantitative in nature; (7) studies must have reported at least one NIS; and (8) studies must address at least one of the following outcomes: nutrition, functional status, or quality of life. Two independent reviewers assessed study quality using a predefined set of criteria. A systematic search yielded 1119 papers, of which 15 met the inclusion criteria. The study reviewed existing evidence of NIS in a variety of HNC survivors ranging from 3 months to greater than 10 years post-chemoradiotherapy treatment. Eight hundred forty-nine study participants were included in the review. Of the 15 studies, 10 were designed as prospective cohort studies, 4 were cross-sectional studies, and 1 was a retrospective cohort

Training programme impact on thermoplastic immobilization for head and neck radiation therapy

International Nuclear Information System (INIS)

Outhwaite, Julie-Anne; McDowall, W. Robert; Marquart, Louise; Rattray, Gregory; Fielding, Andrew; Hargrave, Catriona

2013-01-01

Purpose: To determine whether uniform guidelines and training in the stabilization and formation of thermoplastic shells can improve the reproducibility of set-up for Head and Neck cancer patients. Methods and materials: Image based measurements of the planning and treatment positions for 35 head and neck cancer patients undergoing radical radiotherapy were analysed to provide a baseline of the reproducibility of thermoplastic immobilization. Radiation therapists (RT) were surveyed to establish a perception of their confidence in thermoplastic procedures. An evidence based staff training programme was created and implemented. Set-up reproduction and staff perception were reviewed to measure the impact of the training programme. Results: The mean (SD) 3D vectors of anatomical displacement, measured on the patient images, improved from 4.64 (2.03) for the baseline group compared to 3.02 (1.65) following training (p < 0.01). The proportion of 3D displacements of patient data exceeding 5 mm 3D vector was decreased from 37.1% to 5.7% (p < 0.001) and the 3 mm vector from 85.7% to 42.9% (p < 0.001). The post-training survey scores demonstrated improved confidence in reproducibility of set-up for head and neck patients. Conclusion: The Thermoplastic Shells Training Program has been found to improve the treatment reproducibility for head and neck radiation therapy patients. Uniform guidelines have increased RT confidence in thermoplastic procedures.

Management and outcome of low velocity penetrating head injury caused by impacted foreign bodies.

Science.gov (United States)

Moussa, Wael Mohamed Mohamed; Abbas, Mohamed

2016-05-01

Penetrating head injuries with impacted foreign bodies are rare, associated with a high incidence of morbidity and potentially life-threatening. In this study, we aimed at investigating the outcome of these cases as well as analyzing the factors affecting the prognosis. A retrospective study in which the records of 16 patients who had penetrating head injuries caused by low-velocity impacted foreign bodies were revised. All patients were males with a mean age of 28.9 years (range, 18 to 50 years). The follow-up period ranged from 4 to 13 months with a mean of 8.1 months. Causes of injury were construction accidents in 6 (37.5 %) patients, assault in 6 (37.5 %) and road traffic accidents in 4 (25 %). The impacted objects included a bar of iron, a piece of wood, a nail, a sickle and a piece of glass. Diagnostic computerized tomography (CT) of the brain was carried out on admission in all patients. Thirteen (81.3 %) patients were submitted to surgery, and all had the appropriate management in the form of antibiotics and dehydrating measures as required. The primary outcome measure was the Glasgow Outcome Scale (GOS) at the end of follow-up. At the end of follow-up, ten (62.5 %) patients had a GOS score of 5, two (12.5 %) patients had a score of 4, and four (25 %) patients had a score of 1. Low-velocity penetrating head injuries are most common in young adult males. With the appropriate management, a majority of even the most severe cases can have a favorable outcome.

The influence of gravity on regional lung blood flow in humans: SPECT in the upright and head-down posture.

Science.gov (United States)

Ax, M; Sanchez-Crespo, A; Lindahl, S G E; Mure, M; Petersson, J

2017-06-01

Previous studies in humans have shown that gravity has little influence on the distribution of lung blood flow while changing posture from supine to prone. This study aimed to evaluate the maximal influence of posture by comparison of regional lung blood flow in the upright and head-down posture in 8 healthy volunteers, using a tilt table. Regional lung blood flow was marked by intravenous injection of macroaggregates of human albumin labeled with 99m Tc or 113m In, in the upright and head-down posture, respectively, during tidal breathing. Both radiotracers remain fixed in the lung after administration. The distribution of radioactivity was mapped using quantitative single photon emission computed tomography (SPECT) corrected for attenuation and scatter. All images were obtained supine during tidal breathing. A shift from upright to the head-down posture caused a clear redistribution of blood flow from basal to apical regions. We conclude that posture plays a role for the distribution of lung blood flow in upright humans, and that the influence of posture, and thereby gravity, is much greater in the upright and head-down posture than in horizontal postures. However, the results of the study demonstrate that lung structure is the main determinant of regional blood flow and gravity is a secondary contributor to the distribution of lung blood flow in the upright and head-down positions. NEW & NOTEWORTHY Using a dual-isotope quantitative SPECT method, we demonstrated that although a shift in posture redistributes blood flow in the direction of gravity, the results are also consistent with lung structure being a greater determinant of regional blood flow than gravity. To our knowledge, this is the first study to use modern imaging methods to quantify the shift in regional lung blood flow in humans at a change between the upright and head-down postures. Copyright © 2017 the American Physiological Society.

Characterization of HPV and host genome interactions in primary head and neck cancers

Science.gov (United States)

Parfenov, Michael; Pedamallu, Chandra Sekhar; Gehlenborg, Nils; Freeman, Samuel S.; Danilova, Ludmila; Bristow, Christopher A.; Lee, Semin; Hadjipanayis, Angela G.; Ivanova, Elena V.; Wilkerson, Matthew D.; Protopopov, Alexei; Yang, Lixing; Seth, Sahil; Song, Xingzhi; Tang, Jiabin; Ren, Xiaojia; Zhang, Jianhua; Pantazi, Angeliki; Santoso, Netty; Xu, Andrew W.; Mahadeshwar, Harshad; Wheeler, David A.; Haddad, Robert I.; Jung, Joonil; Ojesina, Akinyemi I.; Issaeva, Natalia; Yarbrough, Wendell G.; Hayes, D. Neil; Grandis, Jennifer R.; El-Naggar, Adel K.; Meyerson, Matthew; Park, Peter J.; Chin, Lynda; Seidman, J. G.; Hammerman, Peter S.; Kucherlapati, Raju; Ally, Adrian; Balasundaram, Miruna; Birol, Inanc; Bowlby, Reanne; Butterfield, Yaron S.N.; Carlsen, Rebecca; Cheng, Dean; Chu, Andy; Dhalla, Noreen; Guin, Ranabir; Holt, Robert A.; Jones, Steven J.M.; Lee, Darlene; Li, Haiyan I.; Marra, Marco A.; Mayo, Michael; Moore, Richard A.; Mungall, Andrew J.; Robertson, A. Gordon; Schein, Jacqueline E.; Sipahimalani, Payal; Tam, Angela; Thiessen, Nina; Wong, Tina; Protopopov, Alexei; Santoso, Netty; Lee, Semin; Parfenov, Michael; Zhang, Jianhua; Mahadeshwar, Harshad S.; Tang, Jiabin; Ren, Xiaojia; Seth, Sahil; Haseley, Psalm; Zeng, Dong; Yang, Lixing; Xu, Andrew W.; Song, Xingzhi; Pantazi, Angeliki; Bristow, Christopher; Hadjipanayis, Angela; Seidman, Jonathan; Chin, Lynda; Park, Peter J.; Kucherlapati, Raju; Akbani, Rehan; Casasent, Tod; Liu, Wenbin; Lu, Yiling; Mills, Gordon; Motter, Thomas; Weinstein, John; Diao, Lixia; Wang, Jing; Fan, You Hong; Liu, Jinze; Wang, Kai; Auman, J. Todd; Balu, Saianand; Bodenheimer, Tom; Buda, Elizabeth; Hayes, D. Neil; Hoadley, Katherine A.; Hoyle, Alan P.; Jefferys, Stuart R.; Jones, Corbin D.; Kimes, Patrick K.; Marron, J.S.; Meng, Shaowu; Mieczkowski, Piotr A.; Mose, Lisle E.; Parker, Joel S.; Perou, Charles M.; Prins, Jan F.; Roach, Jeffrey; Shi, Yan; Simons, Janae V.; Singh, Darshan; Soloway, Mathew G.; Tan, Donghui; Veluvolu, Umadevi; Walter, Vonn; Waring, Scot; Wilkerson, Matthew D.; Wu, Junyuan; Zhao, Ni; Cherniack, Andrew D.; Hammerman, Peter S.; Tward, Aaron D.; Pedamallu, Chandra Sekhar; Saksena, Gordon; Jung, Joonil; Ojesina, Akinyemi I.; Carter, Scott L.; Zack, Travis I.; Schumacher, Steven E.; Beroukhim, Rameen; Freeman, Samuel S.; Meyerson, Matthew; Cho, Juok; Chin, Lynda; Getz, Gad; Noble, Michael S.; DiCara, Daniel; Zhang, Hailei; Heiman, David I.; Gehlenborg, Nils; Voet, Doug; Lin, Pei; Frazer, Scott; Stojanov, Petar; Liu, Yingchun; Zou, Lihua; Kim, Jaegil; Lawrence, Michael S.; Sougnez, Carrie; Lichtenstein, Lee; Cibulskis, Kristian; Lander, Eric; Gabriel, Stacey B.; Muzny, Donna; Doddapaneni, HarshaVardhan; Kovar, Christie; Reid, Jeff; Morton, Donna; Han, Yi; Hale, Walker; Chao, Hsu; Chang, Kyle; Drummond, Jennifer A.; Gibbs, Richard A.; Kakkar, Nipun; Wheeler, David; Xi, Liu; Ciriello, Giovanni; Ladanyi, Marc; Lee, William; Ramirez, Ricardo; Sander, Chris; Shen, Ronglai; Sinha, Rileen; Weinhold, Nils; Taylor, Barry S.; Aksoy, B. Arman; Dresdner, Gideon; Gao, Jianjiong; Gross, Benjamin; Jacobsen, Anders; Reva, Boris; Schultz, Nikolaus; Sumer, S. Onur; Sun, Yichao; Chan, Timothy; Morris, Luc; Stuart, Joshua; Benz, Stephen; Ng, Sam; Benz, Christopher; Yau, Christina; Baylin, Stephen B.; Cope, Leslie; Danilova, Ludmila; Herman, James G.; Bootwalla, Moiz; Maglinte, Dennis T.; Laird, Peter W.; Triche, Timothy; Weisenberger, Daniel J.; Van Den Berg, David J.; Agrawal, Nishant; Bishop, Justin; Boutros, Paul C.; Bruce, Jeff P; Byers, Lauren Averett; Califano, Joseph; Carey, Thomas E.; Chen, Zhong; Cheng, Hui; Chiosea, Simion I.; Cohen, Ezra; Diergaarde, Brenda; Egloff, Ann Marie; El-Naggar, Adel K.; Ferris, Robert L.; Frederick, Mitchell J.; Grandis, Jennifer R.; Guo, Yan; Haddad, Robert I.; Hammerman, Peter S.; Harris, Thomas; Hayes, D. Neil; Hui, Angela BY; Lee, J. Jack; Lippman, Scott M.; Liu, Fei-Fei; McHugh, Jonathan B.; Myers, Jeff; Ng, Patrick Kwok Shing; Perez-Ordonez, Bayardo; Pickering, Curtis R.; Prystowsky, Michael; Romkes, Marjorie; Saleh, Anthony D.; Sartor, Maureen A.; Seethala, Raja; Seiwert, Tanguy Y.; Si, Han; Tward, Aaron D.; Van Waes, Carter; Waggott, Daryl M.; Wiznerowicz, Maciej; Yarbrough, Wendell; Zhang, Jiexin; Zuo, Zhixiang; Burnett, Ken; Crain, Daniel; Gardner, Johanna; Lau, Kevin; Mallery, David; Morris, Scott; Paulauskis, Joseph; Penny, Robert; Shelton, Candance; Shelton, Troy; Sherman, Mark; Yena, Peggy; Black, Aaron D.; Bowen, Jay; Frick, Jessica; Gastier-Foster, Julie M.; Harper, Hollie A.; Lichtenberg, Tara M.; Ramirez, Nilsa C.; Wise, Lisa; Zmuda, Erik; Baboud, Julien; Jensen, Mark A.; Kahn, Ari B.; Pihl, Todd D.; Pot, David A.; Srinivasan, Deepak; Walton, Jessica S.; Wan, Yunhu; Burton, Robert; Davidsen, Tanja; Demchok, John A.; Eley, Greg; Ferguson, Martin L.; Shaw, Kenna R. Mills; Ozenberger, Bradley A.; Sheth, Margi; Sofia, Heidi J.; Tarnuzzer, Roy; Wang, Zhining; Yang, Liming; Zenklusen, Jean Claude; Saller, Charles; Tarvin, Katherine; Chen, Chu; Bollag, Roni; Weinberger, Paul; Golusiński, Wojciech; Golusiński, Paweł; Ibbs, Matthiew; Korski, Konstanty; Mackiewicz, Andrzej; Suchorska, Wiktoria; Szybiak, Bartosz; Wiznerowicz, Maciej; Burnett, Ken; Curley, Erin; Gardner, Johanna; Mallery, David; Penny, Robert; Shelton, Troy; Yena, Peggy; Beard, Christina; Mitchell, Colleen; Sandusky, George; Agrawal, Nishant; Ahn, Julie; Bishop, Justin; Califano, Joseph; Khan, Zubair; Bruce, Jeff P; Hui, Angela BY; Irish, Jonathan; Liu, Fei-Fei; Perez-Ordonez, Bayardo; Waldron, John; Boutros, Paul C.; Waggott, Daryl M.; Myers, Jeff; Lippman, Scott M.; Egea, Sophie; Gomez-Fernandez, Carmen; Herbert, Lynn; Bradford, Carol R.; Carey, Thomas E.; Chepeha, Douglas B.; Haddad, Andrea S.; Jones, Tamara R.; Komarck, Christine M.; Malakh, Mayya; McHugh, Jonathan B.; Moyer, Jeffrey S.; Nguyen, Ariane; Peterson, Lisa A.; Prince, Mark E.; Rozek, Laura S.; Sartor, Maureen A.; Taylor, Evan G.; Walline, Heather M.; Wolf, Gregory T.; Boice, Lori; Chera, Bhishamjit S.; Funkhouser, William K.; Gulley, Margaret L.; Hackman, Trevor G.; Hayes, D. Neil; Hayward, Michele C.; Huang, Mei; Rathmell, W. Kimryn; Salazar, Ashley H.; Shockley, William W.; Shores, Carol G.; Thorne, Leigh; Weissler, Mark C.; Wrenn, Sylvia; Zanation, Adam M.; Chiosea, Simion I.; Diergaarde, Brenda; Egloff, Ann Marie; Ferris, Robert L.; Romkes, Marjorie; Seethala, Raja; Brown, Brandee T.; Guo, Yan; Pham, Michelle; Yarbrough, Wendell G.

2014-01-01

Previous studies have established that a subset of head and neck tumors contains human papillomavirus (HPV) sequences and that HPV-driven head and neck cancers display distinct biological and clinical features. HPV is known to drive cancer by the actions of the E6 and E7 oncoproteins, but the molecular architecture of HPV infection and its interaction with the host genome in head and neck cancers have not been comprehensively described. We profiled a cohort of 279 head and neck cancers with next generation RNA and DNA sequencing and show that 35 (12.5%) tumors displayed evidence of high-risk HPV types 16, 33, or 35. Twenty-five cases had integration of the viral genome into one or more locations in the human genome with statistical enrichment for genic regions. Integrations had a marked impact on the human genome and were associated with alterations in DNA copy number, mRNA transcript abundance and splicing, and both inter- and intrachromosomal rearrangements. Many of these events involved genes with documented roles in cancer. Cancers with integrated vs. nonintegrated HPV displayed different patterns of DNA methylation and both human and viral gene expressions. Together, these data provide insight into the mechanisms by which HPV interacts with the human genome beyond expression of viral oncoproteins and suggest that specific integration events are an integral component of viral oncogenesis. PMID:25313082

Action and reaction of host and pathogen during Fusarium head blight disease

DEFF Research Database (Denmark)

Walter, Stephanie; Nicholson, Paul; Doohan, Fiona M

2010-01-01

The Fusarium species Fusarium graminearum and Fusarium culmorum, Which are responsible for Fusarium head blight (FHB) disease, reduced world-wide cereal crop yield and, as a consequence of their mycotoxin production in cereal grain, impact on both human and animal health. Their study is greatly p...

EVALUATION OF EMF EXPOSURE OF MOBILE PHONES ON HUMAN HEAD

Directory of Open Access Journals (Sweden)

N. I. Vtornikova

2017-01-01

Full Text Available Introduction. Mobile phones are worldwide spread nowadays. Smartphones penetration is growing year after year. Numerous studies indicate the negative effect of EMF exposure of these devices on humans. Therefore, it is important to study the peculiarities of their influence on the target organ-the brain. It is important for solving this problem to find out the real situation of the distribution of energy flux density (EFD of EMF exposure near the front panel of the apparatus.The aim of the study is to determine and compare EMF exposure from smartphones and classic mobile phones on human head.Material and methods. The original method patented in the Russian Federation was used in this study. The used original measuring setup is also patented, developed and assembled by the authors of the study. The object of the study was classical mobile phones and smartphones widespread at the time of work.Results. We got the graphic of matrices of distribution of energy flux density (EFD of EMF exposure in the plane against the front panel of 10 apparatus corresponding to the topography of a human head. The study revealed peculiarities of this distribution in smartphones and the classic mobile phones and got the values of energy flux density (EFD of EMF exposure in the investigated devices acting primarily on the brain.Conclusions. The design of smartphones and mobile phones determines the overall picture of distribution of EFD of EMF exposure in the plane against the front panel for devices of a particular type. This picture must be taken into account when planning epidemiological and experimental studies to obtain comparable results. Progress in the development of mobile communication technologies has led to an increase in the electromagnetic load on users of modern devices.

The Role of Interface on the Impact Characteristics and Cranial Fracture Patterns Using the Immature Porcine Head Model.

Science.gov (United States)

Deland, Trevor S; Niespodziewanski, Emily; Fenton, Todd W; Haut, Roger C

2016-01-01

The role of impact interface characteristics on the biomechanics and patterns of cranial fracture has not been investigated in detail, and especially for the pediatric head. In this study, infant porcine skulls aged 2-19 days were dropped with an energy to cause fracturing onto four surfaces varying in stiffness from a rigid plate to one covered with plush carpeting. Results showed that heads dropped onto the rigid surface produced more extensive cranial fracturing than onto carpeted surfaces. Contact forces generated at fracture initiation and the overall maximum contact forces were generally lower for the rigid than carpeted impacts. While the degree of cranial fracturing from impacts onto the heavy carpeted surface was comparable to that of lower-energy rigid surface impacts, there were fewer diastatic fractures. This suggests that characteristics of the cranial fracture patterns may be used to differentiate energy level from impact interface in pediatric forensic cases. © 2015 American Academy of Forensic Sciences.

Multi-element determination in cancellous bone of human femoral head by PIXE

International Nuclear Information System (INIS)

Yuanxun Zhang; Yongping Zhang; Yongpeng Tong; Shijing Qiu; Xiaotao Wu; Kerong Dai

1996-01-01

Proton Induced X-ray Emission (PIXE) method is used for the determination of elemental concentrations in cancellous bone of human femoral head from five autopsies and seven patients with femoral neck broken. The specimen preparation and experimental procedure are described in detail. Using the t test, the results show that the concentrations of P, Ca, Fe, Cu, Sr in control group are higher than those in patient group, but the concentrations of S, K, Zn, Mn are not significantly different. The physiological functions of metallic elements in human bone are also discussed. (author). 19 refs., 1 fig., 4 tabs

Computed tomography of head: impact of the use of automatic exposure control

International Nuclear Information System (INIS)

Souza, Giordana Salvi de Souza; Froner, Ana Paula Pastre; Silva, Ana Maria Marques da

2017-01-01

The use of dose reduction systems in computed tomography is particularly important for pediatric patients, who have a high radiosensitivity, since they are in the growing phase. The aim of this study was to evaluate the impact of Siemens AEC Care Dose system use on dose estimation in head computed tomography scans in pediatric patients. A retrospective study was conducted with 199 computed tomography head scans of pediatric patients, divided in different age groups, on a 16-channel Siemens Emotion scanner. It was possible to observe, for all age groups, that the use of AEC Care Dose system, not only reduced CTDI vol , but also the interquartile range, reducing the total dose in the investigated population. Concluding, AEC Care Dose system models the tube current according to the patient's dimensions, reducing individual and collective dose without affecting the diagnostic quality . (author)

Human Papilloma Virus Associated Squamous Cell Carcinoma of the Head and Neck

Science.gov (United States)

Ajila, Vidya; Shetty, Harish; Babu, Subhas; Shetty, Veena; Hegde, Shruthi

2015-01-01

Oral cancer is one of the commonest causes for mortality and morbidity with squamous cell carcinoma being the sixth most frequent malignant tumour worldwide. In addition to tobacco and alcohol, human papilloma virus (HPV) is associated with a proportion of head and neck cancers. As in cervical cancers, HPV types 16 and 18 are the cause of malignant transformation. HPV-positive cancers of head and neck have unique characteristics such as occurrence in a younger age group, distinct clinical and molecular features, and better prognosis as compared to HPV-negative carcinomas. They also possess the potential for prevention by using vaccination. The present review describes in detail the salient features of HPV associated oral squamous cell carcinoma (OSCC), its differences from HPV-negative OSCC, diagnostic features, and recent strategies in prevention and management. PMID:26483987

Human Papilloma Virus Associated Squamous Cell Carcinoma of the Head and Neck.

Science.gov (United States)

Ajila, Vidya; Shetty, Harish; Babu, Subhas; Shetty, Veena; Hegde, Shruthi

2015-01-01

Oral cancer is one of the commonest causes for mortality and morbidity with squamous cell carcinoma being the sixth most frequent malignant tumour worldwide. In addition to tobacco and alcohol, human papilloma virus (HPV) is associated with a proportion of head and neck cancers. As in cervical cancers, HPV types 16 and 18 are the cause of malignant transformation. HPV-positive cancers of head and neck have unique characteristics such as occurrence in a younger age group, distinct clinical and molecular features, and better prognosis as compared to HPV-negative carcinomas. They also possess the potential for prevention by using vaccination. The present review describes in detail the salient features of HPV associated oral squamous cell carcinoma (OSCC), its differences from HPV-negative OSCC, diagnostic features, and recent strategies in prevention and management.

Exploratory study on the methodology of fast imaging of unilateral stroke lesions by electrical impedance asymmetry in human heads.

Science.gov (United States)

Ma, Jieshi; Xu, Canhua; Dai, Meng; You, Fusheng; Shi, Xuetao; Dong, Xiuzhen; Fu, Feng

2014-01-01

Stroke has a high mortality and disability rate and should be rapidly diagnosed to improve prognosis. Diagnosing stroke is not a problem for hospitals with CT, MRI, and other imaging devices but is difficult for community hospitals without these devices. Based on the mechanism that the electrical impedance of the two hemispheres of a normal human head is basically symmetrical and a stroke can alter this symmetry, a fast electrical impedance imaging method called symmetrical electrical impedance tomography (SEIT) is proposed. In this technique, electrical impedance tomography (EIT) data measured from the undamaged craniocerebral hemisphere (CCH) is regarded as reference data for the remaining EIT data measured from the other CCH for difference imaging to identify the differences in resistivity distribution between the two CCHs. The results of SEIT imaging based on simulation data from the 2D human head finite element model and that from the physical phantom of human head verified this method in detection of unilateral stroke.

BrainK for Structural Image Processing: Creating Electrical Models of the Human Head

Directory of Open Access Journals (Sweden)

Kai Li

2016-01-01

Full Text Available BrainK is a set of automated procedures for characterizing the tissues of the human head from MRI, CT, and photogrammetry images. The tissue segmentation and cortical surface extraction support the primary goal of modeling the propagation of electrical currents through head tissues with a finite difference model (FDM or finite element model (FEM created from the BrainK geometries. The electrical head model is necessary for accurate source localization of dense array electroencephalographic (dEEG measures from head surface electrodes. It is also necessary for accurate targeting of cerebral structures with transcranial current injection from those surface electrodes. BrainK must achieve five major tasks: image segmentation, registration of the MRI, CT, and sensor photogrammetry images, cortical surface reconstruction, dipole tessellation of the cortical surface, and Talairach transformation. We describe the approach to each task, and we compare the accuracies for the key tasks of tissue segmentation and cortical surface extraction in relation to existing research tools (FreeSurfer, FSL, SPM, and BrainVisa. BrainK achieves good accuracy with minimal or no user intervention, it deals well with poor quality MR images and tissue abnormalities, and it provides improved computational efficiency over existing research packages.

45 CFR 1308.21 - Parent participation and transition of children into Head Start and from Head Start to public...

Science.gov (United States)

2010-10-01

... into Head Start and from Head Start to public school. 1308.21 Section 1308.21 Public Welfare... AND HUMAN SERVICES THE ADMINISTRATION FOR CHILDREN, YOUTH AND FAMILIES, HEAD START PROGRAM HEAD START... Standards § 1308.21 Parent participation and transition of children into Head Start and from Head Start to...

Prognostic factors for head and neck cancer of unknown primary including the impact of human papilloma virus infection.

Science.gov (United States)

Axelsson, Lars; Nyman, Jan; Haugen-Cange, Hedda; Bove, Mogens; Johansson, Leif; De Lara, Shahin; Kovács, Anikó; Hammerlid, Eva

2017-06-10

Head and neck cancer of unknown primary (HNCUP) is rare and prospective studies are lacking. The impact of different prognostic factors such as age and N stage is not completely known, the optimal treatment is not yet established, and the reported survival rates vary. In the last decade, human papilloma virus (HPV) has been identified as a common cause of and important prognostic factor in oropharyngeal cancer, and there is now growing interest in the importance of HPV for HNCUP. The aim of the present study on curatively treated HNCUP was to investigate the prognostic importance of different factors, including HPV status, treatment, and overall survival. A search for HNCUP was performed in the Swedish Cancer Registry, Western health district, between the years 1992-2009. The medical records were reviewed, and only patients with squamous cell carcinoma or undifferentiated carcinoma treated with curative intent were included. The tumor specimens were retrospectively analyzed for HPV with p16 immunostaining. Sixty-eight patients were included. The mean age was 59 years. The majority were males, and had N2 tumors. Sixty-nine percent of the tumors were HPV positive using p16 staining. Patients who were older than 70 years, patients with N3-stage tumors, and patients with tumors that were p16 negative had a significantly worse prognosis. The overall 5-year survival rate for patients with p16-positive tumors was 88% vs 61% for p16-negative tumors. Treatment with neck dissection and postoperative radiation or (chemo) radiation had 81 and 88% 5-year survival rates, respectively. The overall and disease-free 5-year survival rates for all patients in the study were 82 and 74%. Curatively treated HNCUP had good survival. HPV infection was common. Independent prognostic factors for survival were age over 70 years, HPV status and N3 stage. We recommend that HPV analysis should be performed routinely for HNCUP. Treatment with neck dissection and postoperative radiation or

Tribological changes in the articular cartilage of a human femoral head with avascular necrosis.

Science.gov (United States)

Seo, Eun-Min; Shrestha, Suman K; Duong, Cong-Truyen; Sharma, Ashish Ranjan; Kim, Tae-Woo; Vijayachandra, Ayyappan; Thompson, Mark S; Cho, Myung Guk; Park, Sungchan; Kim, Kwanghoon; Park, Seonghun; Lee, Sang-Soo

2015-06-29

The present study evaluated the tribological properties of the articular cartilage surface of the human femoral head with postcollapse stage avascular necrosis (AVN) using atomic force microscopy. The cartilage surface in the postcollapse stage AVN of the femoral head was reported to resemble those of disuse conditions, which suggests that the damage could be reversible and offers the possibilities of success of head-sparing surgeries. By comparing the tribological properties of articular cartilage in AVN with that of osteoarthritis, the authors intended to understand the cartilage degeneration mechanism and reversibility of AVN. Human femoral heads with AVN were explanted from the hip replacement surgery of four patients (60-83 years old). Nine cylindrical cartilage samples (diameter, 5 mm and height, 0.5 mm) were sectioned from the weight-bearing areas of the femoral head with AVN, and the cartilage surface was classified according to the Outerbridge Classification System (AVN0, normal; AVN1, softening and swelling; and AVN2, partial thickness defect and fissuring). Tribological properties including surface roughness and frictional coefficients and histochemistry including Safranin O and lubricin staining were compared among the three groups. The mean surface roughness Rq values of AVN cartilage increased significantly with increasing Outerbridge stages: Rq = 137 ± 26 nm in AVN0, Rq = 274 ± 49 nm in AVN1, and Rq = 452 ± 77 nm in AVN2. Significant differences in Rq were observed among different Outerbridge stages in all cases (p AVN0, μ = 0.143 ± 0.025 in AVN1, and μ = 0.171 ± 0.039 in AVN2. Similarly to the statistical analysis of surface roughness, significant statistical differences were detected between different Outerbridge stages in all cases (p AVN. The underlying mechanism of these results can be related to proteoglycan loss within the articular cartilage that is also observed in osteoarthritis. With regard to the tribological properties, the

Proteomics Analyses of Human Optic Nerve Head Astrocytes Following Biomechanical Strain*

OpenAIRE

Rogers, Ronan S.; Dharsee, Moyez; Ackloo, Suzanne; Sivak, Jeremy M.; Flanagan, John G.

2011-01-01

We investigate the role of glial cell activation in the human optic nerve caused by raised intraocular pressure, and their potential role in the development of glaucomatous optic neuropathy. To do this we present a proteomics study of the response of cultured, optic nerve head astrocytes to biomechanical strain, the magnitude and mode of strain based on previously published quantitative models. In this case, astrocytes were subjected to 3 and 12% stretches for either 2 h or 24 h. Proteomic me...

Novel Method of Weighting Cumulative Helmet Impacts Improves Correlation with Brain White Matter Changes After One Football Season of Sub-concussive Head Blows.

Science.gov (United States)

Merchant-Borna, Kian; Asselin, Patrick; Narayan, Darren; Abar, Beau; Jones, Courtney M C; Bazarian, Jeffrey J

2016-12-01

One football season of sub-concussive head blows has been shown to be associated with subclinical white matter (WM) changes on diffusion tensor imaging (DTI). Prior research analyses of helmet-based impact metrics using mean and peak linear and rotational acceleration showed relatively weak correlations to these WM changes; however, these analyses failed to account for the emerging concept that neuronal vulnerability to successive hits is inversely related to the time between hits (TBH). To develop a novel method for quantifying the cumulative effects of sub-concussive head blows during a single season of collegiate football by weighting helmet-based impact measures for time between helmet impacts. We further aim to compare correlations to changes in DTI after one season of collegiate football using weighted cumulative helmet-based impact measures to correlations using non-weighted cumulative helmet-based impact measures and non-cumulative measures. We performed a secondary analysis of DTI and helmet impact data collected on ten Division III collegiate football players during the 2011 season. All subjects underwent diffusion MR imaging before the start of the football season and within 1 week of the end of the football season. Helmet impacts were recorded at each practice and game using helmet-mounted accelerometers, which computed five helmet-based impact measures for each hit: linear acceleration (LA), rotational acceleration (RA), Gadd Severity Index (GSI), Head Injury Criterion (HIC 15 ), and Head Impact Technology severity profile (HITsp). All helmet-based impact measures were analyzed using five methods of summary: peak and mean (non-cumulative measures), season sum-totals (cumulative unweighted measures), and season sum-totals weighted for time between hits (TBH), the interval of time from hit to post-season DTI assessment (TUA), and both TBH and TUA combined. Summarized helmet-based impact measures were correlated to statistically significant changes in

Density distribution of currents induced inside the brain in the head part of the human model exposed to power frequency electric field

Energy Technology Data Exchange (ETDEWEB)

Chiba, Atsuo [Yongo National Collage of Technology (Japan); Isaka, Katsuo [University of Tokushima (Japan)

1999-07-01

The health effect of the weak current induced in the human body as a result of the interaction between human body and power frequency electric fields has been investigated. However, the current density inside the head part tissues of the human body exposed to the electric fields has rarely been discussed. In this paper, the finite element method is applied to the analysis of the current density distribution of the head part composed of scalp, skull, cerebrospinal liquid and brain tissues. The basic characteristics of the current density distributions of the brain in the asymmetrical human model have been made clear. (author)

Mechanistic Insights into Human Brain Impact Dynamics through Modal Analysis

Science.gov (United States)

Laksari, Kaveh; Kurt, Mehmet; Babaee, Hessam; Kleiven, Svein; Camarillo, David

2018-03-01

Although concussion is one of the greatest health challenges today, our physical understanding of the cause of injury is limited. In this Letter, we simulated football head impacts in a finite element model and extracted the most dominant modal behavior of the brain's deformation. We showed that the brain's deformation is most sensitive in low frequency regimes close to 30 Hz, and discovered that for most subconcussive head impacts, the dynamics of brain deformation is dominated by a single global mode. In this Letter, we show the existence of localized modes and multimodal behavior in the brain as a hyperviscoelastic medium. This dynamical phenomenon leads to strain concentration patterns, particularly in deep brain regions, which is consistent with reported concussion pathology.

'Goats that stare at men'--revisited: do dwarf goats alter their behaviour in response to eye visibility and head direction of a human?

Science.gov (United States)

Nawroth, Christian; von Borell, Eberhard; Langbein, Jan

2016-05-01

Being able to recognise when one is being observed by someone else is thought to be adaptive during cooperative or competitive events. In particular for prey species, this ability should be of use in the context of predation. A previous study reported that goats (Capra aegagrus hircus) alter their behaviour according to the body and head orientation of a human experimenter. During a food anticipation task, an experimenter remained in a particular posture for 30 s before delivering a reward, and the goats' active anticipation and standing alert behaviour were analysed. To further evaluate the specific mechanisms at work, we here present two additional test conditions. In particular, we investigated the effects of the eye visibility and head orientation of a human experimenter on the behaviour of the goats (N = 7). We found that the level of the subjects' active anticipatory behaviour was highest in the conditions where the experimenter was directing his head and body towards the goat ('Control' and 'Eyes closed' conditions), but the anticipatory behaviour was significantly decreased when the body ('Head only') or the head and body of the experimenter were directed away from the subject ('Back' condition). For standing alert, we found no significant differences between the three conditions in which the experimenter was directing his head towards the subject ('Control', 'Eyes closed' and 'Head only'). This lack of differences in the expression of standing alert suggests that goats evaluate the direction of a human's head as an important cue in their anticipatory behaviour. However, goats did not respond to the visibility of the experimenter's eyes alone.

Head Worn Display System for Equivalent Visual Operations

Science.gov (United States)

Cupero, Frank; Valimont, Brian; Wise, John; Best. Carl; DeMers, Bob

2009-01-01

Head-Worn Displays or so-called, near-to-eye displays have potentially significant advantages in terms of cost, overcoming cockpit space constraints, and for the display of spatially-integrated information. However, many technical issues need to be overcome before these technologies can be successfully introduced into commercial aircraft cockpits. The results of three activities are reported. First, the near-to-eye display design, technological, and human factors issues are described and a literature review is presented. Second, the results of a fixed-base piloted simulation, investigating the impact of near to eye displays on both operational and visual performance is reported. Straight-in approaches were flown in simulated visual and instrument conditions while using either a biocular or a monocular display placed on either the dominant or non-dominant eye. The pilot's flight performance, visual acuity, and ability to detect unsafe conditions on the runway were tested. The data generally supports a monocular design with minimal impact due to eye dominance. Finally, a method for head tracker system latency measurement is developed and used to compare two different devices.

Facial preservation following extreme mummification: Shrunken heads.

Science.gov (United States)

Houlton, Tobias M R; Wilkinson, Caroline

2018-05-01

Shrunken heads are a mummification phenomenon unique to South America. Ceremonial tsantsa are ritually reduced heads from enemy victims of the Shuar, Achuar, Awajún (Aguaruna), Wampís (Huambisa), and Candoshi-Shapra cultures. Commercial shrunken heads are comparatively modern and fraudulently produced for the curio-market, often using stolen bodies from hospital mortuaries and graves. To achieve shrinkage and desiccation, heads undergo skinning, simmering (in water) and drying. Considering the intensive treatments applied, this research aims to identify how the facial structure can alter and impact identification using post-mortem depiction. Sixty-five human shrunken heads were assessed: 6 ceremonial, 36 commercial, and 23 ambiguous. Investigations included manual inspection, multi-detector computerised tomography, infrared reflectography, ultraviolet fluorescence and microscopic hair analysis. The mummification process disfigures the outer face, cheeks, nasal root and bridge form, including brow ridge, eyes, ears, mouth, and nose projection. Melanin depletion, epidermal degeneration, and any applied staining changes the natural skin complexion. Papillary and reticular dermis separation is possible. Normal hair structure (cuticle, cortex, medulla) is retained. Hair appears longer (unless cut) and more profuse following shrinkage. Significant features retained include skin defects, facial creases, hairlines and earlobe form. Hair conditions that only affect living scalps are preserved (e.g. nits, hair casts). Ear and nose cartilage helps to retain some morphological information. Commercial heads appear less distorted than ceremonial tsantsa, often presenting a definable eyebrow shape, vermillion lip shape, lip thickness (if mouth is open), philtrum form, and palpebral slit angle. Facial identification capabilities are considered limited, and only perceived possible for commercial heads. Copyright © 2018 Elsevier B.V. All rights reserved.

29 CFR 1926.100 - Head protection.

Science.gov (United States)

2010-07-01

... 29 Labor 8 2010-07-01 2010-07-01 false Head protection. 1926.100 Section 1926.100 Labor... § 1926.100 Head protection. (a) Employees working in areas where there is a possible danger of head... protected by protective helmets. (b) Helmets for the protection of employees against impact and penetration...

[Ex vivo microCT analysis of possible microfractures of the femoral head during implantation of a cementless hip resurfacing femoral component].

Science.gov (United States)

Lerch, M; Olender, G; von der Höh, N; Thorey, F; von Lewinski, G; Meyer-Lindenberg, A; Windhagen, H; Hurschler, C

2009-01-01

Microfractures of the femoral head during implantation of the femoral components are suspected to be a cause of fractures at the implant/neck junction which represent a common failure mode in hip resurfacing arthroplasty. Callus formation observed in femoral head retrievals suggests the occurrence of microfractures inside the femoral head, which might be inadvertently caused by the surgeon during implantation. The aim of this biomechanical study was to analyse whether or not the implantation of a cementless femoral component hip resurfacing system causes microfractures in the femoral head. After the preparation of 20 paired human cadaveric femoral heads, the cementless femoral component ESKA Typ BS (ESKA Implants GmbH & Co., Lübeck) was implanted on 9 specimens with an impaction device that generates 4.5 kN impaction force. On 9 specimens the femoral component was implanted by hand. One head was used as a fracture model, 1 specimen served as control without manipulation. The femoral component used for impaction was equipped with hinges to enable its removal without further interfering with the bone stock. Specimens were scanned with a microCT device before and after impaction and the microCT datasets before and after impaction were compared to identify possible microfractures. Twenty strikes per hand or with the impaction device provided sufficient implant seating. Neither the macroscopic examination nor the 2-dimensional microCT analysis revealed any fractures of the femoral heads after impaction. At least macroscopically and in the 2-dimensional microCT analysis, implantation of the cementless hip resurfacing femoral component ESKA Typ BS with 4.5 kN or by hand does not seem to cause fractures of the femoral head. Georg Thieme Verlag KG Stuttgart, New York.

Experience and lessons from health impact assessment for human rights impact assessment.

Science.gov (United States)

Salcito, Kendyl; Utzinger, Jürg; Krieger, Gary R; Wielga, Mark; Singer, Burton H; Winkler, Mirko S; Weiss, Mitchell G

2015-09-16

As globalisation has opened remote parts of the world to foreign investment, global leaders at the United Nations and beyond have called on multinational companies to foresee and mitigate negative impacts on the communities surrounding their overseas operations. This movement towards corporate impact assessment began with a push for environmental and social inquiries. It has been followed by demands for more detailed assessments, including health and human rights. In the policy world the two have been joined as a right-to-health impact assessment. In the corporate world, the right-to-health approach fulfils neither managers' need to comprehensively understand impacts of a project, nor rightsholders' need to know that the full suite of their human rights will be safe from violation. Despite the limitations of a right-to-health tool for companies, integration of health into human rights provides numerous potential benefits to companies and the communities they affect. Here, a detailed health analysis through the human rights lens is carried out, drawing on a case study from the United Republic of Tanzania. This paper examines the positive and negative health and human rights impacts of a corporate operation in a low-income setting, as viewed through the human rights lens, considering observations on the added value of the approach. It explores the relationship between health impact assessment (HIA) and human rights impact assessment (HRIA). First, it considers the ways in which HIA, as a study directly concerned with human welfare, is a more appropriate guide than environmental or social impact assessment for evaluating human rights impacts. Second, it considers the contributions HRIA can make to HIA, by viewing determinants of health not as direct versus indirect, but as interrelated.

A micro-architectural evaluation of osteoporotic human femoral heads to guide implant placement in proximal femoral fractures.

Science.gov (United States)

Jenkins, Paul J; Ramaesh, Rishikesan; Pankaj, Pankaj; Patton, James T; Howie, Colin R; Goffin, Jérôme M; Merwe, Andrew van der; Wallace, Robert J; Porter, Daniel E; Simpson, A Hamish

2013-10-01

The micro-architecture of bone has been increasingly recognized as an important determinant of bone strength. Successful operative stabilization of fractures depends on bone strength. We evaluated the osseous micro-architecture and strength of the osteoporotic human femoral head. 6 femoral heads, obtained during arthroplasty surgery for femoral neck fracture, underwent micro-computed tomography (microCT) scanning at 30 μm, and bone volume ratio (BV/TV), trabecular thickness, structural model index, connection density, and degree of anisotropy for volumes of interest throughout the head were derived. A further 15 femoral heads underwent mechanical testing of compressive failure stress of cubes of trabecular bone from different regions of the head. The greatest density and trabecular thickness was found in the central core that extended from the medial calcar to the physeal scar. This region also correlated with the greatest degree of anisotropy and proportion of plate-like trabeculae. In the epiphyseal region, the trabeculae were organized radially from the physeal scar. The weakest area was found at the apex and peripheral areas of the head. The strongest region was at the center of the head. The center of the femoral head contained the strongest trabecular bone, with the thickest, most dense trabeculae. The apical region was weaker. From an anatomical and mechanical point of view, implants that achieve fixation in or below this central core may achieve the most stable fixation during fracture healing.

How big of an effect do small dams have? Using geomorphological footprints to quantify spatial impact of low-head dams and identify patterns of across-dam variation

Science.gov (United States)

Fencl, Jane S.; Mather, Martha E.; Costigan, Katie H.; Daniels, Melinda D.

2015-01-01

Longitudinal connectivity is a fundamental characteristic of rivers that can be disrupted by natural and anthropogenic processes. Dams are significant disruptions to streams. Over 2,000,000 low-head dams (research and conservation is impaired by not knowing the magnitude of low-head dam impacts. Based on the geomorphic literature, we refined a methodology that allowed us to quantify the spatial extent of low-head dam impacts (herein dam footprint), assessed variation in dam footprints across low-head dams within a river network, and identified select aspects of the context of this variation. Wetted width, depth, and substrate size distributions upstream and downstream of six low-head dams within the Upper Neosho River, Kansas, United States of America were measured. Total dam footprints averaged 7.9 km (3.0–15.3 km) or 287 wetted widths (136–437 wetted widths). Estimates included both upstream (mean: 6.7 km or 243 wetted widths) and downstream footprints (mean: 1.2 km or 44 wetted widths). Altogether the six low-head dams impacted 47.3 km (about 17%) of the mainstem in the river network. Despite differences in age, size, location, and primary function, the sizes of geomorphic footprints of individual low-head dams in the Upper Neosho river network were relatively similar. The number of upstream dams and distance to upstream dams, but not dam height, affected the spatial extent of dam footprints. In summary, ubiquitous low-head dams individually and cumulatively altered lotic ecosystems. Both characteristics of individual dams and the context of neighboring dams affected low-head dam impacts within the river network. For these reasons, low-head dams require a different, more integrative, approach for research and management than the individualistic approach that has been applied to larger dams.

Impact of Terrorism on Managerial Efficiency of Heads of Secondary Schools in Khyber Pakhtunkhwa, Pakistan

Science.gov (United States)

Khattak, Usman Ghani; Iqba, Javed

2015-01-01

Terrorism has adversely affected the educational environment in Khyber Pakhtoon Khwa Province. This study was conducted to know the impact of Terrorism on managerial efficiency of heads of secondary schools in Khyber Pakhtoon Khwa that included Malakand, Mangawara, Dir, Hangu , Bannu and D I Khan which are the highly affected areas of terrorism.…

Effect of head restraint backset on head-neck kinematics in whiplash.

Science.gov (United States)

Stemper, Brian D; Yoganandan, Narayan; Pintar, Frank A

2006-03-01

Although head restraints were introduced in the 1960s as a countermeasure for whiplash, their limited effectiveness has been attributed to incorrect positioning. The effect of backset on cervical segmental angulations, which were previously correlated with spinal injury, has not been delineated. Therefore, the practical restraint position to minimize injury remains unclear. A parametric study of increasing head restraint backset between 0 and 140mm was conducted using a comprehensively validated computational model. Head retraction values increased with increasing backset, reaching a maximum value of 53.5mm for backsets greater than 60mm. Segmental angulation magnitudes, greatest at levels C5-C6 and C6-C7, reached maximum values during the retraction phase and increased with increasing backset. Results were compared to a previously published head restraint rating system, wherein lower cervical extension magnitudes from this study exceeded mean physiologic limits for restraint positions rated good, acceptable, marginal, and poor. As head restraint contact was the limiting factor in head retraction and segmental angulations, the present study indicates that minimizing whiplash injury may be accomplished by limiting head restraint backset to less than 60mm either passively or actively after impact.

Active Head Restraints Used to Improve the Car Seats Safety in a Rear Impact Situation, in Accordance with the Requirements of EURO NCAP

Directory of Open Access Journals (Sweden)

D. Yu. Solopov

2014-01-01

Full Text Available This article is devoted to the urgent, presently, problem that is to ensure the best level of the passive safety of car seats with active head restraints, as well as to assess the effectiveness of such constructional designs. This is an impact-related task, to be, as a consequence, essentially nonlinear with large deformations, strains and accelerations.To solve this problem finite element models of three types of seat designs with active head restraints have been developed. When creating the simulation FEM a number of CAD (Computer Aided Design/CAE (Computer Aided Engineering software was used.This work was performed within the framework of the developed technique, which allows an efficient creation of the car seat designs with passive and active head restraints that meet requirements of the passive safety.The results of calculations and experiments allowed us to find that the active head restraint significantly reduced a NIC (Neck Injury Criterion value, namely up to 36.92 (4% when using the active headrest with articulated tilting couch, 29.23 (per 24% when using the active headrest with sliding pad, and 26.15 (31% when using the active head restraint, which is provided with an airbag. We have also managed to achieve significantly reduced head acceleration under impact.It was found that FEM seats with active head restraint, which is provided with an airbag, are the most secure because of the least NIC value under the impact (26.15.Presented in the article materials are used in teaching students at the department “Wheeled vehicles” of scientific and educational complex "Special engineering" in BMSTU.

Analysis of real-time head accelerations in collegiate football players.

Science.gov (United States)

Duma, Stefan M; Manoogian, Sarah J; Bussone, William R; Brolinson, P Gunnar; Goforth, Mike W; Donnenwerth, Jesse J; Greenwald, Richard M; Chu, Jeffrey J; Crisco, Joseph J

2005-01-01

To measure and analyze head accelerations during American collegiate football practices and games. A newly developed in-helmet 6-accelerometer system that transmits data via radio frequency to a sideline receiver and laptop computer system was implemented. From the data transfer of these accelerometer traces, the sideline staff has real-time data including the head acceleration, the head injury criteria value, the severity index value, and the impact location. Data are presented for instrumented players for the entire 2003 football season, including practices and games. American collegiate football. Thirty-eight players from Virginia Tech's varsity football team. Accelerations and pathomechanics of head impacts. : A total of 3312 impacts were recorded over 35 practices and 10 games for 38 players. The average peak head acceleration, Gadd Severity Index, and Head Injury Criteria were 32 g +/- 25 g, 36 g +/- 91 g, and 26 g +/- 64 g, respectively. One concussive event was observed with a peak acceleration of 81 g, a 267 Gadd Severity Index, and 200 Head Injury Criteria. Because the concussion was not reported until the day after of the event, a retrospective diagnosis based on his history and clinical evaluation suggested a mild concussion. The primary finding of this study is that the helmet-mounted accelerometer system proved effective at collecting thousands of head impact events and providing contemporaneous head impact parameters that can be integrated with existing clinical evaluation techniques.

Multi-sector thermo-physiological head simulator for headgear research

Science.gov (United States)

Martinez, Natividad; Psikuta, Agnes; Corberán, José Miguel; Rossi, René M.; Annaheim, Simon

2017-02-01

A novel thermo-physiological human head simulator for headgear testing was developed by coupling a thermal head manikin with a thermo-physiological model. As the heat flux at head-site is directly measured by the head manikin, this method provides a realistic quantification of the heat transfer phenomena occurring in the headgear, such as moisture absorption-desorption cycles, condensation, or moisture migration across clothing layers. Before coupling, the opportunities of the head manikin for representing the human physiology were evaluated separately. The evaluation revealed reduced precision in forehead and face temperature predictions under extreme heterogeneous temperature distributions and no initial limitation for simulating temperature changes observed in the human physiology. The thermo-physiological model predicted higher sweat rates when applied for coupled than for pure virtual simulations. After coupling, the thermo-physiological human head simulator was validated using eight human experiments. It precisely predicted core, mean skin, and forehead temperatures with average rmsd values within the average experimental standard deviation (rmsd of 0.20 ± 0.15, 0.83 ± 0.34, and 1.04 ± 0.54 °C, respectively). However, in case of forehead, precision was lower for the exposures including activity than for the sedentary exposures. The representation of the human sweat evaporation could be affected by a reduced evaporation efficiency and the manikin sweat dynamics. The industry will benefit from this thermo-physiological human head simulator leading to the development of helmet designs with enhanced thermal comfort and, therefore, with higher acceptance by users.

Multi-sector thermo-physiological head simulator for headgear research.

Science.gov (United States)

Martinez, Natividad; Psikuta, Agnes; Corberán, José Miguel; Rossi, René M; Annaheim, Simon

2017-02-01

A novel thermo-physiological human head simulator for headgear testing was developed by coupling a thermal head manikin with a thermo-physiological model. As the heat flux at head-site is directly measured by the head manikin, this method provides a realistic quantification of the heat transfer phenomena occurring in the headgear, such as moisture absorption-desorption cycles, condensation, or moisture migration across clothing layers. Before coupling, the opportunities of the head manikin for representing the human physiology were evaluated separately. The evaluation revealed reduced precision in forehead and face temperature predictions under extreme heterogeneous temperature distributions and no initial limitation for simulating temperature changes observed in the human physiology. The thermo-physiological model predicted higher sweat rates when applied for coupled than for pure virtual simulations. After coupling, the thermo-physiological human head simulator was validated using eight human experiments. It precisely predicted core, mean skin, and forehead temperatures with average rmsd values within the average experimental standard deviation (rmsd of 0.20 ± 0.15, 0.83 ± 0.34, and 1.04 ± 0.54 °C, respectively). However, in case of forehead, precision was lower for the exposures including activity than for the sedentary exposures. The representation of the human sweat evaporation could be affected by a reduced evaporation efficiency and the manikin sweat dynamics. The industry will benefit from this thermo-physiological human head simulator leading to the development of helmet designs with enhanced thermal comfort and, therefore, with higher acceptance by users.

Infrared Non-Contact Head Sensor for Control of Wheelchair Movements

DEFF Research Database (Denmark)

Christensen, Henrik Vie; Garcia, Juan Carlos

2005-01-01

This paper presents a new human-machine interface for controlling a wheelchair by head movements. The position of the head is determined by use of infrared sensors, with no parts attached to the head of the user. The placement of the infrared sensors are behind the head of the user, so that the f......This paper presents a new human-machine interface for controlling a wheelchair by head movements. The position of the head is determined by use of infrared sensors, with no parts attached to the head of the user. The placement of the infrared sensors are behind the head of the user, so...

Rotational Acceleration during Head Impact Resulting from Different Judo Throwing Techniques

OpenAIRE

MURAYAMA, Haruo; HITOSUGI, Masahito; MOTOZAWA, Yasuki; OGINO, Masahiro; KOYAMA, Katsuhiro

2014-01-01

Most severe head injuries in judo are reported as acute subdural hematoma. It is thus necessary to examine the rotational acceleration of the head to clarify the mechanism of head injuries. We determined the rotational acceleration of the head when the subject is thrown by judo techniques. One Japanese male judo expert threw an anthropomorphic test device using two throwing techniques, Osoto-gari and Ouchigari. Rotational and translational head accelerations were measured with and without an ...

Study of exogenous factors on the state and properties of hair on the human head by using various methods of microscopy

Directory of Open Access Journals (Sweden)

Neofitova E.A.

2016-12-01

Full Text Available in the article the effect of exogenous factors on the state and properties of hair on the human head using various techniques of microscopy as well as other morphometric methods are studied; on the basis of experimental samples the physical properties of healthy hair and the hair damaged by external factors by using microscopy techniques were compared; the article presents the values of pH and the content of surfactants (sulfates in different brands of shampoos and soaps, and their impact on the condition of the hair was determined; on the basis of microscopy techniques the condition of the cuticle after using different detergents for hair care was characterized; a relationship between the color of the hair and the influence of external factors on the structure and condition of the hair was analyzed; the signs of the impact of external factors (chemical, thermal, mechanical on the state and structure of the hair, using an optical (light and an usb-microscopes were identified.

Effects of Soccer Heading on Brain Structure and Function

Science.gov (United States)

Rodrigues, Ana Carolina; Lasmar, Rodrigo Pace; Caramelli, Paulo

2016-01-01

Soccer is the most popular sport in the world, with more than 265 million players worldwide, including professional and amateur ones. Soccer is unique in comparison to other sports, as it is the only sport in which participants purposely use their head to hit the ball. Heading is considered as an offensive or defensive move whereby the player’s unprotected head is used to deliberately impact the ball and direct it during play. A soccer player can be subjected to an average of 6–12 incidents of heading the ball per competitive game, where the ball reaches high velocities. Moreover, in practice sessions, heading training, which involves heading the ball repeatedly at low velocities, is common. Although the scientific community, as well as the media, has focused on the effects of concussions in contact sports, the role of subconcussive impacts, as it can occur during heading, has recently gained attention, considering that it may represent an additional mechanism of cumulative brain injury. The purpose of this study is to review the existing literature regarding the effects of soccer heading on brain structure and function. Only in the last years, some investigations have addressed the impact of heading on brain structure, by using neuroimaging techniques. Similarly, there have been some recent studies investigating biochemical markers of brain injury in soccer players. There is evidence of association between heading and abnormal brain structure, but the data are still preliminary. Also, some studies have suggested that subconcussive head impacts, as heading, could cause cognitive impairment, whereas others have not corroborated this finding. Questions persist as to whether or not heading is deleterious to cognitive functioning. Further studies, especially with longitudinal designs, are needed to clarify the clinical significance of heading as a cause of brain injury and to identify risk factors. Such investigations might contribute to the establishment of safety

Effects of soccer heading on brain structure and function

Directory of Open Access Journals (Sweden)

Ana Carolina Oliveira Rodrigues

2016-03-01

Full Text Available Soccer is the most popular sport in the world, with more than 265 million players worldwide, including professional and amateur ones. Soccer is unique in comparison to other sports, as it is the only sport in which participants purposely use their head to hit the ball. Heading is considered an offensive or defensive move whereby the player’s unprotected head is used to deliberately impact the ball and direct it during play. A soccer player can be subjected to an average of six to twelve incidents of heading the ball per competitive game, where the ball reaches high velocities. Moreover, in practice sessions, heading training, which involves heading the ball repeatedly at low velocities, is common. Although the scientific community, as well as the media, has focused on the effects of concussions in contact sports, the role of subconcussive impacts, as it can occur during heading, has recently gained attention, considering that it may represent an additional mechanism of cumulative brain injury. The purpose of this study is to review the existing literature regarding the effects of soccer heading on brain structure and function. Only in the last years some investigations have addressed the impact of heading on brain structure, by using neuroimaging techniques. Similarly, there have been some recent studies investigating biochemical markers of brain injury in soccer players. There is evidence of association between heading and abnormal brain structure, but the data are still preliminary. Also, some studies have suggested that subconcussive head impacts, as heading, could cause cognitive impairment, whereas others have not corroborated this finding. Questions persist as to whether or not heading is deleterious to cognitive functioning. Further studies, especially with longitudinal designs, are needed to clarify the clinical significance of heading as a cause of brain injury and to identify risk factors. Such investigations might contribute to the

[Human papilloma viruses: other risk factor of head and neck carcinoma].

Science.gov (United States)

Woto-Gaye, G; M'Farrej, M K; Doh, K; Thiam, I; Touré, S; Diop, R; Dial, C

2016-08-01

Head and neck carcinoma (HNC) occupy the sixth place as the most frequent type of cancer worldwide. Next to alcohol and tobacco intoxication, other risk factors (RF) are suspected, including the human papilloma viruses (HPVs). The aim of this study was to highlight the prevalence of HPVs and histo-epidemiological characteristics of HNC HPV+ in Senegal. This is a prospective, multicenter preliminary study of 18 months (January 1, 2012-June 30, 2014). The cases of HNC histologically confirmed in Senegal were then sent to the bio-pathology department of the Curie Institute in Paris to search HPVs. In the 90 included cases, the PCR technique was successful in 54 cases (60%). HPVs were found in seven cases, that is, a prevalence of 13%. HPVs were associated with 5 cases of hypopharyngeal carcinoma and 2 cases of carcinoma of the oral cavity. Patients with HNC HPV+ had a median age of 42 years against 49 years for HPV-patients. Three patients (42.8%) with HPV+ carcinomas were smokers. Of the 47 HPV-patients, 40 patients (87.1%) had alcohol intoxication and/or smoking. The concept of oral sex was refuted by all our patients. Squamous cell carcinoma was the only histological type found. HPV+ cell carcinoma showed no specific histological appearance. HPVs are another certain RF of HNC in Senegal. The major therapeutic and prognostic impact of HPVinduced cancers requires the systematic search of the viruses by the PCR technique.

Less efficient oculomotor performance is associated with increased incidence of head impacts in high school ice hockey.

Science.gov (United States)

Kiefer, Adam W; DiCesare, Christopher; Nalepka, Patrick; Foss, Kim Barber; Thomas, Staci; Myer, Gregory D

2018-01-01

To evaluate associations between pre-season oculomotor performance on visual tracking tasks and in-season head impact incidence during high school boys ice hockey. Prospective observational study design. Fifteen healthy high school aged male hockey athletes (M=16.50±1.17years) performed two 30s blocks each of a prosaccade and self-paced saccade task, and two trials each of a slow, medium, and fast smooth pursuit task (90°s -1 ; 180°s -1 ; 360°s -1 ) during the pre-season. Regular season in-game collision data were collected via helmet-mounted accelerometers. Simple linear regressions were used to examine relations between oculomotor performance measures and collision incidence at various impact thresholds. The variability of prosaccade latency was positively related to total collisions for the 20g force cutoff (p=0.046, adjusted R 2 =0.28). The average self-paced saccade velocity (p=0.020, adjusted R 2 =0.37) and variability of smooth pursuit gaze velocity (p=0.012, adjusted R 2 =0.47) were also positively associated with total collisions for the 50g force cutoff. These results provide preliminary evidence that less efficient oculomotor performance on three different oculomotor tasks is associated with increased incidence of head impacts during a competitive ice hockey season. The variability of prosaccade latency, the average self-paced saccade velocity and the variability of gaze velocity during predictable smooth pursuit all related to increased head impacts. Future work is needed to further understand player initiated collisions, but this is an important first step toward understanding strategies to reduce incidence of injury risk in ice hockey, and potentially contact sports more generally. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Diagnostics of femoral head status in humans using laser spectroscopy - In vitro studies.

Science.gov (United States)

Lin, Huiying; Li, Wansha; Zhang, Hao; Chen, Peng; Chen, Delong; He, Wei; Svanberg, Sune; Svanberg, Katarina

2017-10-01

Osteonecrosis of the femoral head (ONFH), a recalcitrant and disabling disease, is caused by inadequate or fully disrupted blood supply to the affected segment of the subchondral bone. Theoretically, there will develop gas-filled pores during the bone decay process due to lacking blood supply. Unfortunately, the relationship between the gas-filled pores and ONFH is still unclear. Here, we have introduced diode laser absorption spectroscopy to detect oxygen and water vapor signals in the femoral heads from hip replacement in 19 patients. Five samples are affected by osteoarthritis (OA) and the others are related to ONFH. Oxygen and water vapor signals could be obtained, demonstrating the presence of gas-filled pores in both the OA and ONFH groups while the measurement results showed no significant difference. A study of gas exchange was also performed on one excised bone sample to study how these gas pores communicate with the ambient air. The results suggested that the obtained oxygen signals inside the bone samples originate from the invasion of ambient air, which is not expected in vivo. In conclusion, the ability to detect the gas signal of laser absorption spectroscopy shows the potential for the medical application of assessing the human femoral head in vivo. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Radio frequency-induced temperature elevations in the human head considering small anatomical structures

International Nuclear Information System (INIS)

Schmid, G.; Ueberbacher, R.; Samaras, T.

2007-01-01

In order to enable a detailed numerical radio frequency (RF) dosimetry and the computations of RF-induced temperature elevations, high-resolution (0.1 mm) numerical models of the human eye, the inner ear organs and the pineal gland were developed and inserted into a commercially available head model. As radiation sources, generic models of handsets at 400, 900 and 1850 MHz operating in close proximity to the head were considered. The results, obtained by finite-difference time domain-based computations, showed a highly heterogeneous specific absorption rate (SAR) distribution and SAR-peaks inside the inner ear structures; however, the corresponding RF-induced temperature elevations were well below 0.1 deg. C, when considering typical output power values of hand-held devices. In case of frontal exposure, with the radiation sources ∼2.5 cm in front of the closed eye, maximum temperature elevations in the eye in the range of ∼0.2-0.6 deg. C were found for typical device output powers. A reduction in tissue perfusion mainly affected the maximum RF-induced temperature elevation of tissues deep inside the head. Similarly, worst-case considerations regarding pulsed irradiation affected temperature elevations in deep tissue significantly more than in superficial tissues. (authors)

Neck injury tolerance under inertial loads in side impacts.

Science.gov (United States)

McIntosh, Andrew S; Kallieris, Dimitrios; Frechede, Bertrand

2007-03-01

Neck injury remains a major issue in road safety. Current side impact dummies and side impact crashworthiness assessments do not assess the risk of neck injury. These assessments are limited by biofidelity and knowledge regarding neck injury criteria and tolerance levels in side impacts. Side impact tests with PMHS were performed at the Heidelberg University in the 1980s and 1990s to improve primarily the understanding of trunk dynamics, injury mechanisms and criteria. In order to contribute to the definition of human tolerances at neck level, this study presents an analysis of the head/neck biomechanical parameters that were measured in these tests and their relationship to neck injury severity. Data from 15 impact tests were analysed. Head accelerations, and neck forces and moments were calculated from 9-accelerometer array head data, X-rays and anthropometric data. Statistically significant relationships were observed between resultant head acceleration and neck force and neck injury severity. The average resultant head acceleration for AIS 2 neck injuries was 112 g, while resultant neck force was 4925 N and moment 241 Nm. The data compared well to other test data on cadavers and volunteers. It is hoped that the paper will assist in the understanding of neck injuries and the development of tolerance criteria.

Impact of conventional radiotherapy on health-related quality of life and critical functions of the head and neck

International Nuclear Information System (INIS)

Connor, Nadine P.; Cohen, Stacy B. M.A.; Kammer, Rachael E.; Sullivan, Paula A.; Brewer, Kathryn A.; Hong, Theodore S.; Chappell, Richard J.; Harari, Paul M.

2006-01-01

Purpose: Head-and-neck radiotherapy is associated with significant morbidities. Our purpose was to document impact of morbidities by use of multiple objective measures and health-related quality of life (HR-QOL). Methods and Materials: Ten head-and-neck cancer patients were evaluated before receiving conventional head-and-neck radiotherapy and at 1 month and 6 months after treatment. We evaluated weight, saliva production, diet, swallow function, auditory function, and HR-QOL. Results: After radiotherapy, weight was reduced in 89% of subjects. Salivary function was significantly reduced and did not resolve by 6 months. Diet impairment and abnormalities in swallowing function persisted at 6 months. Perception of physical functioning was reduced after treatment, and swallowing, coughing, and dry-mouth symptoms increased. Very few changes were observed in auditory function. Conclusions: Conventional head-and-neck radiotherapy is associated with substantial functional deficits and diminished HR-QOL. Deficits reported here can serve as a baseline for comparison with results derived from new radiotherapy-treatment techniques

Impact of Gender Binarism on Hijras' Life Course and Their Access to Fundamental Human Rights in Pakistan.

Science.gov (United States)

Alizai, Aurangzaib; Doneys, Philippe; Doane, Donna L

2017-01-01

This study adds to the growing body of knowledge on gender nonconformity aspects of heteronormativity by examining its impact on the life course of hijras and their access to fundamental human rights in Pakistan. Drawing on 50 semistructured interviews conducted in two sites, the findings suggest that the participants' lived experiences associated with gender nonconformity significantly influenced the direction of their life course and their ability to have access to human rights. These experiences spanned from childhood to elderhood across a wide range of settings, such as family, school, guru dera (residence headed by a hijra guru), workplace, and interactions with authorities. The participants' human rights were not recognized, resulting in abuse, social stigma, discrimination against them, and their exclusion from mainstream society. Finally, implications are drawn for public policy and future research on third gender concerns in Pakistan and elsewhere.

Heads Up: Concussion in Youth Sports

Medline Plus

Full Text Available ... with HEADS UP & CDC's Injury Center HEADS UP Resources File Formats Help: How do I view different ... 6348 Email CDC-INFO U.S. Department of Health & Human Services HHS/Open USA.gov Top

Humanoid Robot Head Design Based on Uncanny Valley and FACS

Directory of Open Access Journals (Sweden)

Jizheng Yan

2014-01-01

Full Text Available Emotional robots are always the focus of artificial intelligence (AI, and intelligent control of robot facial expression is a hot research topic. This paper focuses on the design of humanoid robot head, which is divided into three steps to achieve. The first step is to solve the uncanny valley about humanoid robot, to find and avoid the relationship between human being and robot; the second step is to solve the association between human face and robot head; compared with human being and robots, we analyze the similarities and differences and explore the same basis and mechanisms between robot and human analyzing the Facial Action Coding System (FACS, which guides us to achieve humanoid expressions. On the basis of the previous two steps, the third step is to construct a robot head; through a series of experiments we test the robot head, which could show some humanoid expressions; through human-robot interaction, we find people are surprised by the robot head expression and feel happy.

Picture THIS: Taking Human Impact Seriously

Science.gov (United States)

Patrick, Patricia; Patrick, Tammy

2010-01-01

Unfortunately, middle school students often view human impact as an abstract idea over which they have no control and do not see themselves as contributing to the Earth's environmental decline. How better to uncover students' ideas concerning human impact in their local community than to have them take photographs. With this objective in mind, the…

SAR analysis of a needle type applicator made from a shape memory alloy using 3-D anatomical human head model

International Nuclear Information System (INIS)

Kubo, Mitsunori; Mimoto, Naoki; Hirashima, Taku; Morita, Emi; Shindo, Yasuhiro; Kato, Kazuo; Takahashi, Hideaki; Uzuka, Takeo; Fujii, Yukihiko

2009-01-01

This paper describes the possibility of a new heating method with a needle applicator made of a shape memory alloy (SMA) to expand the heating area for interstitial brain tumor hyperthermia treatments. The purpose of the study described here is to show the capability of the method to expand a defined heating region with the developed three-dimensional (3-D) anatomical human head model using the finite element method (FEM). One major disadvantage of radiofrequency (RF) interstitial hyperthermia treatment is that this heating method has a small heating area. To overcome this problem, a new type of needle made of a SMA was developed. The specific absorption rate (SAR) distributions of this proposed method, when applied to the 3-D anatomical human head model reconstructed from two-dimensional (2-D) MRI and X-ray CT images, were calculated with computer simulations. The calculated SAR distributions showed no unexpected hot spots within the model. The heated area was localized around the tumor. These results suggest that the proposed heating method using the SMA needle applicator and the developed method for reconstructing a 3-D anatomical human head model are capable of being used for invasive brain tumor hyperthermia treatments. (author)

Understanding the Societal Impact of Humanities Scholarship

DEFF Research Database (Denmark)

Pedersen, David Budtz; Johansson, Lasse Gøhler

2016-01-01

in society. An important assumption in this paper is that impact should be studied both from conceptual, qualitative and quantitative perspectives. Any approach that focuses merely on scientific outputs (such as publications or citations) or that relies on purely bibliometric indicators will result...... both quantitative and qualitative tools, the paper argues that we need a better and more comprehensive understanding of the role the humanities as part of a wider web of societal institutions, networks, and agents. Granted that the impact of humanities breakthroughs cannot be located at clearly......The critical problem for understanding the societal impact of humanities scholarship is that we currently have no satisfactory tools for understanding how wider social impacts occur and, by implication, very few guidelines for stimulating a reflexive dialogue about the influence of the humanities...

Human impact gradient on mammalian biodiversity

Directory of Open Access Journals (Sweden)

Mariana Munguía

2016-04-01

Full Text Available Drastic changes have been caused by human influence in natural landscapes, which may exert an intensive effect on species loss. However, species loss from human pressure is not random but depends on a series of environmentally associated factors. Linking species traits to environmental attributes may allow us to detect the ecological impacts of habitat so that meaningful habitat degradation gradients can be identified. The relationships between environmental factors and species traits provide the basis for identifying those biological traits that make species more sensitive to disturbance. These relationships are also helpful to detect the geographic distribution of latent risk to reveal areas where biodiversity is threatened. Here, we identify a “Human Impact Gradient for Biodiversity (HIGB” based on a three-table ordination method (RLQ analysis and fourth-corner analysis to identify key species traits that are associated with environmental gradient. Species distribution and environmental geographic data were gathered nationwide to analyze 68 localities, which represent 27% of Mexico’s surface, including 211 species of mammals. Nine environmental variables (including biophysical, geophysical and land-use impacts were analyzed by using the Geographic Information System. Three types of species’ traits were evaluated: locomotion, trophic habit and body size. We identified a human impact gradient, which was mainly determined by the percentage of the area that was covered by seedlings, the plant richness, the understory coverage percentage and the human settlement index. The most important species traits that are associated with non-human-impacted sites were carnivores, frugivores–herbivores and a body size that was greater than 17.8 kg; 25 species were selected by the decision criteria framework for species that were sensitive to degradation based on ecological function information. Conversely, granivores, fossorial and semifossorial

Conceiving Human Interaction by Visualising Depth Data of Head Pose Changes and Emotion Recognition via Facial Expressions

Directory of Open Access Journals (Sweden)

Grigorios Kalliatakis

2017-07-01

Full Text Available Affective computing in general and human activity and intention analysis in particular comprise a rapidly-growing field of research. Head pose and emotion changes present serious challenges when applied to player’s training and ludology experience in serious games, or analysis of customer satisfaction regarding broadcast and web services, or monitoring a driver’s attention. Given the increasing prominence and utility of depth sensors, it is now feasible to perform large-scale collection of three-dimensional (3D data for subsequent analysis. Discriminative random regression forests were selected in order to rapidly and accurately estimate head pose changes in an unconstrained environment. In order to complete the secondary process of recognising four universal dominant facial expressions (happiness, anger, sadness and surprise, emotion recognition via facial expressions (ERFE was adopted. After that, a lightweight data exchange format (JavaScript Object Notation (JSON is employed, in order to manipulate the data extracted from the two aforementioned settings. Motivated by the need to generate comprehensible visual representations from different sets of data, in this paper, we introduce a system capable of monitoring human activity through head pose and emotion changes, utilising an affordable 3D sensing technology (Microsoft Kinect sensor.

Rotational acceleration during head impact resulting from different judo throwing techniques.

Science.gov (United States)

Murayama, Haruo; Hitosugi, Masahito; Motozawa, Yasuki; Ogino, Masahiro; Koyama, Katsuhiro

2014-01-01

Most severe head injuries in judo are reported as acute subdural hematoma. It is thus necessary to examine the rotational acceleration of the head to clarify the mechanism of head injuries. We determined the rotational acceleration of the head when the subject is thrown by judo techniques. One Japanese male judo expert threw an anthropomorphic test device using two throwing techniques, Osoto-gari and Ouchi-gari. Rotational and translational head accelerations were measured with and without an under-mat. For Osoto-gari, peak resultant rotational acceleration ranged from 4,284.2 rad/s(2) to 5,525.9 rad/s(2) and peak resultant translational acceleration ranged from 64.3 g to 87.2 g; for Ouchi-gari, the accelerations respectively ranged from 1,708.0 rad/s(2) to 2,104.1 rad/s(2) and from 120.2 g to 149.4 g. The resultant rotational acceleration did not decrease with installation of an under-mat for both Ouchi-gari and Osoto-gari. We found that head contact with the tatami could result in the peak values of translational and rotational accelerations, respectively. In general, because kinematics of the body strongly affects translational and rotational accelerations of the head, both accelerations should be measured to analyze the underlying mechanism of head injury. As a primary preventative measure, throwing techniques should be restricted to participants demonstrating ability in ukemi techniques to avoid head contact with the tatami.

Development of Head Injury Assessment Reference Values Based on NASA Injury Modeling

Science.gov (United States)

Somers, Jeffrey T.; Melvin, John W.; Tabiei, Ala; Lawrence, Charles; Ploutz-Snyder, Robert; Granderson, Bradley; Feiveson, Alan; Gernhardt, Michael; Patalak, John

2011-01-01

NASA is developing a new capsule-based, crewed vehicle that will land in the ocean, and the space agency desires to reduce the risk of injury from impact during these landings. Because landing impact occurs for each flight and the crew might need to perform egress tasks, current injury assessment reference values (IARV) were deemed insufficient. Because NASCAR occupant restraint systems are more effective than the systems used to determine the current IARVs and are similar to NASA s proposed restraint system, an analysis of NASCAR impacts was performed to develop new IARVs that may be more relevant to NASA s context of vehicle landing operations. Head IARVs associated with race car impacts were investigated by completing a detailed analysis of all of the 2002-2008 NASCAR impact data. Specific inclusion and exclusion criteria were used to select 4071 impacts from the 4015 recorder files provided (each file could contain multiple impact events). Of the 4071 accepted impacts, 274 were selected for numerical simulation using a custom NASCAR restraint system and Humanetics Hybrid-III 50th percentile numerical dummy model in LS-DYNA. Injury had occurred in 32 of the 274 selected impacts, and 27 of those injuries involved the head. A majority of the head injuries were mild concussions with or without brief loss of consciousness. The 242 non-injury impacts were randomly selected and representative of the range of crash dynamics present in the total set of 4071 impacts. Head dynamics data (head translational acceleration, translational change in velocity, rotational acceleration, rotational velocity, HIC-15, HIC-36, and the Head 3ms clip) were filtered according to SAE J211 specifications and then transformed to a log scale. The probability of head injury was estimated using a separate logistic regression analysis for each log-transformed predictor candidate. Using the log transformation constrains the estimated probability of injury to become negligible as IARVs approach

Conceiving Human Interaction by Visualising Depth Data of Head Pose Changes and Emotion Recognition via Facial Expressions

NARCIS (Netherlands)

Kalliatakis, Grigorios; Stergiou, A.G.; Vidakis, Nikolaos

2017-01-01

Affective computing in general and human activity and intention analysis in particular comprise a rapidly-growing field of research. Head pose and emotion changes present serious challenges when applied to player’s training and ludology experience in serious games, or analysis of customer

Trichostatin A, a histone deacetylase inhibitor, potentiated cytotoxic effect of lionizing radiation in human head and neck cancer cell lines

International Nuclear Information System (INIS)

Kim, Jin Ho; Shin, Jin Hee; Chie, Eui Kyu; Wu, Hong Gyun; Kim, Jae Sung; Kim, Il Han; Ha, Sung Whan; Park, Charn Il; Kang, Wee Saing

2004-01-01

We have previously reported that human glioblastoma cells are sensitized to radiation-induced death after their exposure to trichostatin A (TSA), a histone deacetylase inhibitor (HDAC-I), prior to the irradiation. We aimed to measure the magnitude of the radiosensitizing effect of TSA in human head and neck cancer cell lines. human head and neck cancer cell lines, HN-3 and HN-9, were exposed to 0, 50, 100, and 200 nM TSA for 18 hr prior to irradiation. Then, the TSA-treated cells were irradiated with 0, 2, 4, 6, and 8 Gy, and cell survival was measured by clonogenic assay. Pre-irradiation exposure to TSA was found to radiosensitize HN-3 and HN-9 cell lines. In HN-9 cells, the fraction surviving after 2 Gy (SF2) was significantly reduced by treatment of TSA at concentration as low as 50 nM. However, a treatment with 200 nM TSA was required to significantly decrease SF2 in the HN-3 cell line. SER of pre-irradiation treatment with 200 nM TSA was 1.84 in HN-3 and 7.24 in HN-9, respectively. Our results clearly showed that human head and neck cancer cell lines can be sensitized to ionizing radiation by pre-irradiation inhibition of histone deacetylase (HDAC) using TSA, and that this potentiation might well be a general phenomenon

Thermal effects of dorsal head immersion in cold water on nonshivering humans.

Science.gov (United States)

Giesbrecht, Gordon G; Lockhart, Tamara L; Bristow, Gerald K; Steinman, Allan M

2005-11-01

Personal floatation devices maintain either a semirecumbent flotation posture with the head and upper chest out of the water or a horizontal flotation posture with the dorsal head and whole body immersed. The contribution of dorsal head and upper chest immersion to core cooling in cold water was isolated when the confounding effect of shivering heat production was inhibited with meperidine (Demerol, 2.5 mg/kg). Six male volunteers were immersed four times for up to 60 min, or until esophageal temperature = 34 degrees C. An insulated hoodless dry suit or two different personal floatation devices were used to create four conditions: 1) body insulated, head out; 2) body insulated, dorsal head immersed; 3) body exposed, head (and upper chest) out; and 4) body exposed, dorsal head (and upper chest) immersed. When the body was insulated, dorsal head immersion did not affect core cooling rate (1.1 degrees C/h) compared with head-out conditions (0.7 degrees C/h). When the body was exposed, however, the rate of core cooling increased by 40% from 3.6 degrees C/h with the head out to 5.0 degrees C/h with the dorsal head and upper chest immersed (P immersed (approximately 10%). The exaggerated core cooling during dorsal head immersion (40% increase) may result from the extra heat loss affecting a smaller thermal core due to intense thermal stimulation of the body and head and resultant peripheral vasoconstriction. Dorsal head and upper chest immersion in cold water increases the rate of core cooling and decreases potential survival time.

Impacts of “metals” on human health

DEFF Research Database (Denmark)

Pizzol, Massimo; Christensen, Per; Schmidt, Jannick Højrup

2011-01-01

This paper looks into the differences and uncertainties in determining the impact of “metals” emissions on human health, in Life Cycle Impact Assessment (LCIA). Metals are diverse substances, with different properties and characteristics, considered important in LCIA because of their toxicity...... to humans and ecosystems. First, we defined a list of the most significant metals in terms of impacts on human health. This was done according to precise criteria accounting for both physical and toxic properties of the metals. Second, we performed a LCIA on different key processes using various existing...... to the total impact on human health changes greatly according to the LCIA method used. These differences are due mainly to the number of metals included in each method and to the technique used to calculate the characterization factors. Results obtained with USEtox show no apparent correlation with results...

Do head-restraints protect the neck from whiplash injuries?

Science.gov (United States)

Morris, F

1989-01-01

Over an 11-month period a study was made of all patients presenting to an accident and emergency department who had sustained whiplash as a result of rear-bumper impacts. The patients were analysed with respect to the presence of head-restraints in their vehicles. A significant increase in the incidence of whiplash was found in patients whose vehicles did not have head-restraints fitted. Legislation requiring all passenger cars to have head-restraints fitted as standard would have a major impact in reducing the number of whiplash injuries sustained in rear bumper impacts. PMID:2712983

TCGA head Neck

Science.gov (United States)

Investigators with The Cancer Genome Atlas (TCGA) Research Network have discovered genomic differences – with potentially important clinical implications – in head and neck cancers caused by infection with the human papillomavirus (HPV).

On the pressure response in the brain due to short duration blunt impacts.

Directory of Open Access Journals (Sweden)

Christopher W Pearce

Full Text Available When the head is subject to non-penetrating (blunt impact, contusion-type injuries are commonly identified beneath the impact site (the coup and, in some instances, at the opposite pole (the contre-coup. This pattern of injury has long eluded satisfactory explanation and blunt head injury mechanisms in general remain poorly understood. There are only a small number of studies in the open literature investigating the head's response to short duration impacts, which can occur in collisions with light projectiles. As such, the head impact literature to date has focussed almost exclusively on impact scenarios which lead to a quasi-static pressure response in the brain. In order to investigate the response of the head to a wide range of impact durations, parametric numerical studies were performed on a highly bio-fidelic finite element model of the human head created from in vivo magnetic resonance imaging (MRI scan data with non-linear tissue material properties. We demonstrate that short duration head impacts can lead to potentially deleterious transients of positive and negative intra-cranial pressure over an order of magnitude larger than those observed in the quasi-static regime despite reduced impact force and energy. The onset of this phenomenon is shown to be effectively predicted by the ratio of impact duration to the period of oscillation of the first ovalling mode of the system. These findings point to dramatically different pressure distributions in the brain and hence different patterns of injury depending on projectile mass, and provide a potential explanation for dual coup/contre-coup injuries observed clinically.

A Novel Cellular Handset Design for an Enhanced Antenna Performance and a Reduced SAR in the Human Head

Directory of Open Access Journals (Sweden)

Salah I. Al-Mously

2008-01-01

Full Text Available This paper presents a novel cellular handset design with a bottom-mounted short loaded-whip antenna. This new handset design is modeled and simulated using a finite difference time-domain (FDTD-based platform SEMCAD. The proposed handset is based on a current commercially available bar-phone type with a curvature shape, keypad positioned above the screen, and top-mounted antenna. The specific absorption rates (SARs are determined computationally in the specific anthropomorphic mannequin (SAM and anatomically correct model of a human head when exposed to the EM-field radiation of the proposed cellular handset and the handset with top-mounted antenna. The two cellular handsets are simulated to operate at both GSM standards, 900 MHz as well as 1800 MHz, having different antenna dimensions and intput power of 0.6 W and 0.125 W, respectively. The proposed human hand holding the two handset models is a semirealistic hand model consists of three tissues: skin, muscle, and bone. The simulations are conducted with handset positions based on the IEEE standard 1528-2003. The results show that the proposed handset has a significant improvement of antenna efficiency when it is hand-held close to head, as compared with the handset of top-mounted antenna. Also, the results show that a significant reduction of the induced SAR in the human head-tissues can be achieved with the proposed handset.

Impacts of exhalation flow on the microenvironment around the human body under different room temperatures

Science.gov (United States)

Jafari, Mohammad Javad; Gharari, Noradin; Azari, Mansour Rezazade; Ashrafi, Khosro

2018-04-01

Exhalation flow and room temperature can have a considerable effect on the microenvironment in the vicinity of human body. In this study, impacts of exhalation flow and room temperature on the microenvironment around a human body were investigated using a numerical simulation. For this purpose, a computational fluid dynamic program was applied to study thermal plume around a sitting human body at different room temperatures of a calm indoor room by considering the exhalation flow. The simulation was supported by some experimental measurements. Six different room temperatures (18 to 28 °C) with two nose exhalation modes (exhalation and non-exhalation) were investigated. Overhead and breathing zone velocities and temperatures were simulated in different scenarios. This study finds out that the exhalation through the nose has a significant impact on both quantitative and qualitative features of the human microenvironment in different room temperatures. At a given temperature, the exhalation through the nose can change the location and size of maximum velocity at the top of the head. In the breathing zone, the effect of exhalation through the nose on velocity and temperature distribution was pronounced for the point close to mouth. Also, the exhalation through the nose strongly influences the thermal boundary layer on the breathing zone while it only minimally influences the convective boundary layer on the breathing zone. Overall results demonstrate that it is important to take the exhalation flow into consideration in all areas, especially at a quiescent flow condition with low temperature.

Cumulative human impacts on marine predators.

Science.gov (United States)

Maxwell, Sara M; Hazen, Elliott L; Bograd, Steven J; Halpern, Benjamin S; Breed, Greg A; Nickel, Barry; Teutschel, Nicole M; Crowder, Larry B; Benson, Scott; Dutton, Peter H; Bailey, Helen; Kappes, Michelle A; Kuhn, Carey E; Weise, Michael J; Mate, Bruce; Shaffer, Scott A; Hassrick, Jason L; Henry, Robert W; Irvine, Ladd; McDonald, Birgitte I; Robinson, Patrick W; Block, Barbara A; Costa, Daniel P

2013-01-01

Stressors associated with human activities interact in complex ways to affect marine ecosystems, yet we lack spatially explicit assessments of cumulative impacts on ecologically and economically key components such as marine predators. Here we develop a metric of cumulative utilization and impact (CUI) on marine predators by combining electronic tracking data of eight protected predator species (n=685 individuals) in the California Current Ecosystem with data on 24 anthropogenic stressors. We show significant variation in CUI with some of the highest impacts within US National Marine Sanctuaries. High variation in underlying species and cumulative impact distributions means that neither alone is sufficient for effective spatial management. Instead, comprehensive management approaches accounting for both cumulative human impacts and trade-offs among multiple stressors must be applied in planning the use of marine resources.

Single season changes in resting state network power and the connectivity between regions distinguish head impact exposure level in high school and youth football players

Science.gov (United States)

Murugesan, Gowtham; Saghafi, Behrouz; Davenport, Elizabeth; Wagner, Ben; Urban, Jillian; Kelley, Mireille; Jones, Derek; Powers, Alex; Whitlow, Christopher; Stitzel, Joel; Maldjian, Joseph; Montillo, Albert

2018-02-01

The effect of repetitive sub-concussive head impact exposure in contact sports like American football on brain health is poorly understood, especially in the understudied populations of youth and high school players. These players, aged 9-18 years old may be particularly susceptible to impact exposure as their brains are undergoing rapid maturation. This study helps fill the void by quantifying the association between head impact exposure and functional connectivity, an important aspect of brain health measurable via resting-state fMRI (rs-fMRI). The contributions of this paper are three fold. First, the data from two separate studies (youth and high school) are combined to form a high-powered analysis with 60 players. These players experience head acceleration within overlapping impact exposure making their combination particularly appropriate. Second, multiple features are extracted from rs-fMRI and tested for their association with impact exposure. One type of feature is the power spectral density decomposition of intrinsic, spatially distributed networks extracted via independent components analysis (ICA). Another feature type is the functional connectivity between brain regions known often associated with mild traumatic brain injury (mTBI). Third, multiple supervised machine learning algorithms are evaluated for their stability and predictive accuracy in a low bias, nested cross-validation modeling framework. Each classifier predicts whether a player sustained low or high levels of head impact exposure. The nested cross validation reveals similarly high classification performance across the feature types, and the Support Vector, Extremely randomized trees, and Gradboost classifiers achieve F1-score up to 75%.

The impact of reorienting cone-beam computed tomographic images in varied head positions on the coordinates of anatomical landmarks

Energy Technology Data Exchange (ETDEWEB)

Kim, Jae Hun; Jeong, Ho Gul; Hwang, Jae Joon; Lee, Jung Hee; Han, Sang Sun [Dept. of Oral and Maxillofacial Radiology, Yonsei University, College of Dentistry, Seoul (Korea, Republic of)

2016-06-15

The aim of this study was to compare the coordinates of anatomical landmarks on cone-beam computed tomographic (CBCT) images in varied head positions before and after reorientation using image analysis software. CBCT images were taken in a normal position and four varied head positions using a dry skull marked with 3 points where gutta percha was fixed. In each of the five radiographic images, reference points were set, 20 anatomical landmarks were identified, and each set of coordinates was calculated. Coordinates in the images from the normally positioned head were compared with those in the images obtained from varied head positions using statistical methods. Post-reorientation coordinates calculated using a three-dimensional image analysis program were also compared to the reference coordinates. In the original images, statistically significant differences were found between coordinates in the normal-position and varied-position images. However, post-reorientation, no statistically significant differences were found between coordinates in the normal-position and varied-position images. The changes in head position impacted the coordinates of the anatomical landmarks in three-dimensional images. However, reorientation using image analysis software allowed accurate superimposition onto the reference positions.

The role of human papillomavirus in head and neck cancer in Senegal.

Science.gov (United States)

Ndiaye, Cathy; Alemany, Laia; Diop, Yankhoba; Ndiaye, Nafissatou; Diémé, Marie-Joseph; Tous, Sara; Klaustermeier, Jo Ellen; Alejo, Maria; Castellsagué, Xavier; Bosch, F Xavier; Trottier, Helen; Sanjosé, Silvia de

2013-04-17

Exploring the presence and role of human papillomavirus (HPV) in head and neck cancer (HNC) is a necessary step to evaluate the potential impact of HPV prophylactic vaccines. To assess the prevalence and oncogenic role of HPV in HNC in Senegal. This is a multicenter cross-sectional study. Paraffin-embedded blocks of cases diagnosed with invasive HNC between 2002 and 2010 were collected from 4 pathology laboratories in Senegal. Presence of HPV DNA was determined by PCR and DEIA, and genotyping performed with LiPA25. Tubulin analysis was performed to assess DNA quality. HPV DNA-positive cases were tested for p16INK4a expression. A total of 117 cases were included in the analysis: 71% were men, mean age was 52 years old (SD ±18.3), and 96% of cases were squamous cell carcinoma. Analysis was performed on 41 oral cavity tumors, 64 laryngeal tumors, 5 oropharyngeal tumors and 7 pharyngeal tumors. Only four cases (3.4%; 95% CI = 0.9%-8.5%) harbored HPV DNA. HPV types detected were HPV16, HPV35 and HPV45. However, among HPV-positive cases, none showed p16INK4a overexpression. Our findings indicate that HPV DNA prevalence in HNC in Senegal is very low, suggesting that HPV is not a strong risk factor for these cancers. Additional larger studies are needed to confirm these findings and explore other potential risk factors specific to the region.

Tolerances of the human brain to concussion.

Science.gov (United States)

1971-03-01

The report reviews the pertinent literature and adds additional evidence indicating that the human brain may be able to tolerate head impact forces in the range of 300 to 400 g's without evidence of concussion or other detectable neurologic sequelae,...

Multigenerational Head Start Participation: An Unexpected Marker of Progress

Science.gov (United States)

Chor, Elise

2018-01-01

One-quarter of the Head Start population has a mother who participated in the program as a child. This study uses experimental Head Start Impact Study (HSIS) data on 3- and 4-year-olds (N = 2,849) to describe multigenerational Head Start families and their program experiences. In sharp contrast to full-sample HSIS findings, Head Start has large,…

Early Head Start Evaluation

Data.gov (United States)

U.S. Department of Health & Human Services — Longitudinal information from an evaluation where children were randomly assigned to Early Head Start or community services as usual;direct assessments and...

Does Head Start differentially benefit children with risks targeted by the program's service model?

Science.gov (United States)

Miller, Elizabeth B; Farkas, George; Duncan, Greg J

Data from the Head Start Impact Study ( N = 3540) were used to test for differential benefits of Head Start after one program year and after kindergarten on pre-academic and behavior outcomes for children at risk in the domains targeted by the program's comprehensive services. Although random assignment to Head Start produced positive treatment main effects on children's pre-academic skills and behavior problems, residualized growth models showed that random assignment to Head Start did not differentially benefit the pre-academic skills of children with risk factors targeted by the Head Start service model. The models showed detrimental impacts of Head Start for maternal-reported behavior problems of high-risk children, but slightly more positive impacts for teacher-reported behavior. Policy implications for Head Start are discussed.

Heading-vector navigation based on head-direction cells and path integration.

Science.gov (United States)

Kubie, John L; Fenton, André A

2009-05-01

, heading-based navigation is used in small mammals and humans. Copyright 2008 Wiley-Liss, Inc.

Impact of Globalization on the Human Resource Management ...

African Journals Online (AJOL)

Impact of Globalization on the Human Resource Management Function in ... impact on the management of human resources in developing countries including Kenya. ... The non-core jobs have been outsourced which has led to an increase in ...

Survival of patients with head and neck cancer. Impact of physical status and comorbidities

Energy Technology Data Exchange (ETDEWEB)

Sadat, F. [Friedrich Alexander Univ., Erlangen (Germany). Clinic of Radiotherapy; Wienke, A. [Martin Luther Univ. Halle-Wittenberg, Halle/Saale (Germany). Inst. of Medical Epidemiology; Dunst, J. [Schleswig-Holstein Univ., Luebeck (Germany). Clinic of Radiotherapy; Kuhnt, T. [Rostock Univ. (Germany). Dept. of Radiation Oncology

2012-01-15

Prognostic factors (e.g., gender, tumor stage, and hypoxia) have an impact on survival in patients with head and neck cancer. Thus, the impact of physical status and comorbidities on treatment decision and survival were evaluated. Patients and methods A total of 169 primary, inoperable patients with squamous cell cancer of the head and neck were retrospectively investigated. Patients were treated with hyperfractionated accelerated radio(chemo)therapy (HARcT) or hypofractionated radio(chemo)therapy (HypoRcT). Depending on the individual patient's situation (Karnofsky Performance Index, KPI), treatment for patients with a KPI of 80-100% was generally radiochemotherapy and for patients with a KPI {<=} 70% treatment was radiotherapy alone. In addition, all comorbidities were evaluated. Uni- and multivariate proportional hazards model were used, and overall survival (OS) was estimated by the Kaplan-Meier method. Results Treatment consisted of HARcT for 76 patients (45%), HART for 28 patients (17%), HypoRcT for 14 patients(8%), and HypoRT for 51 patients (30%). Of the patients, 107 patients (63%) presented with a KPI of 80-100%. OS (20%) was significantly better for patients with a KPI of 80-100%, while the OS for patients with a KPI {<=} 70% was 8% (p < 0.001). Good KPI, total irradiation dose (> 70 Gy), and chemotherapy were significant prognostic factors for better OS. Conclusion Our retrospective analysis shows that performance status with dependency on comorbidities was an independent risk factor for OS. (orig.)

Survival of patients with head and neck cancer. Impact of physical status and comorbidities.

Science.gov (United States)

Sadat, F; Wienke, A; Dunst, J; Kuhnt, T

2012-01-01

Prognostic factors (e.g., gender, tumor stage, and hypoxia) have an impact on survival in patients with head and neck cancer. Thus, the impact of physical status and comorbidities on treatment decision and survival were evaluated. A total of 169 primary, inoperable patients with squamous cell cancer of the head and neck were retrospectively investigated. Patients were treated with hyperfractionated accelerated radio(chemo)therapy (HARcT) or hypofractionated radio(chemo)therapy (HypoRcT). Depending on the individual patient's situation (Karnofsky Performance Index, KPI), treatment for patients with a KPI of 80-100% was generally radiochemotherapy and for patients with a KPI ≤ 70% treatment was radiotherapy alone. In addition, all comorbidities were evaluated. Uni- and multivariate proportional hazards model were used, and overall survival (OS) was estimated by the Kaplan-Meier method. Treatment consisted of HARcT for 76 patients (45%), HART for 28 patients (17%), HypoRcT for 14 patients(8%), and HypoRT for 51 patients (30%). Of the patients, 107 patients (63%) presented with a KPI of 80-100%. OS (20%) was significantly better for patients with a KPI of 80-100%, while the OS for patients with a KPI ≤ 70% was 8% (p KPI, total irradiation dose (> 70 Gy), and chemotherapy were significant prognostic factors for better OS. Our retrospective analysis shows that performance status with dependency on comorbidities was an independent risk factor for OS.

Survival of patients with head and neck cancer. Impact of physical status and comorbidities

International Nuclear Information System (INIS)

Sadat, F.; Wienke, A.; Dunst, J.; Kuhnt, T.

2012-01-01

Prognostic factors (e.g., gender, tumor stage, and hypoxia) have an impact on survival in patients with head and neck cancer. Thus, the impact of physical status and comorbidities on treatment decision and survival were evaluated. Patients and methods A total of 169 primary, inoperable patients with squamous cell cancer of the head and neck were retrospectively investigated. Patients were treated with hyperfractionated accelerated radio(chemo)therapy (HARcT) or hypofractionated radio(chemo)therapy (HypoRcT). Depending on the individual patient's situation (Karnofsky Performance Index, KPI), treatment for patients with a KPI of 80-100% was generally radiochemotherapy and for patients with a KPI ≤ 70% treatment was radiotherapy alone. In addition, all comorbidities were evaluated. Uni- and multivariate proportional hazards model were used, and overall survival (OS) was estimated by the Kaplan-Meier method. Results Treatment consisted of HARcT for 76 patients (45%), HART for 28 patients (17%), HypoRcT for 14 patients(8%), and HypoRT for 51 patients (30%). Of the patients, 107 patients (63%) presented with a KPI of 80-100%. OS (20%) was significantly better for patients with a KPI of 80-100%, while the OS for patients with a KPI ≤ 70% was 8% (p 70 Gy), and chemotherapy were significant prognostic factors for better OS. Conclusion Our retrospective analysis shows that performance status with dependency on comorbidities was an independent risk factor for OS. (orig.)

Human Papillomavirus Genome Integration and Head and Neck Cancer.

Science.gov (United States)

Pinatti, L M; Walline, H M; Carey, T E

2018-06-01

We conducted a critical review of human papillomavirus (HPV) integration into the host genome in oral/oropharyngeal cancer, reviewed the literature for HPV-induced cancers, and obtained current data for HPV-related oral and oropharyngeal cancers. In addition, we performed studies to identify HPV integration sites and the relationship of integration to viral-host fusion transcripts and whether integration is required for HPV-associated oncogenesis. Viral integration of HPV into the host genome is not required for the viral life cycle and might not be necessary for cellular transformation, yet HPV integration is frequently reported in cervical and head and neck cancer specimens. Studies of large numbers of early cervical lesions revealed frequent viral integration into gene-poor regions of the host genome with comparatively rare integration into cellular genes, suggesting that integration is a stochastic event and that site of integration may be largely a function of chance. However, more recent studies of head and neck squamous cell carcinomas (HNSCCs) suggest that integration may represent an additional oncogenic mechanism through direct effects on cancer-related gene expression and generation of hybrid viral-host fusion transcripts. In HNSCC cell lines as well as primary tumors, integration into cancer-related genes leading to gene disruption has been reported. The studies have shown that integration-induced altered gene expression may be associated with tumor recurrence. Evidence from several studies indicates that viral integration into genic regions is accompanied by local amplification, increased expression in some cases, interruption of gene expression, and likely additional oncogenic effects. Similarly, reported examples of viral integration near microRNAs suggest that altered expression of these regulatory molecules may also contribute to oncogenesis. Future work is indicated to identify the mechanisms of these events on cancer cell behavior.

Validation and calibration of HeadCount, a self-report measure for quantifying heading exposure in soccer players.

Science.gov (United States)

Catenaccio, E; Caccese, J; Wakschlag, N; Fleysher, R; Kim, N; Kim, M; Buckley, T A; Stewart, W F; Lipton, R B; Kaminski, T; Lipton, M L

2016-01-01

The long-term effects of repetitive head impacts due to heading are an area of increasing concern, and exposure must be accurately measured; however, the validity of self-report of cumulative soccer heading is not known. In order to validate HeadCount, a 2-week recall questionnaire, the number of player-reported headers was compared to the number of headers observed by trained raters for a men's and a women's collegiate soccer teams during an entire season of competitive play using Spearman's correlations and intraclass correlation coefficients (ICCs), and calibrated using a generalized estimating equation. The average Spearman's rho was 0.85 for men and 0.79 for women. The average ICC was 0.75 in men and 0.38 in women. The calibration analysis demonstrated that men tend to report heading accurately while women tend to overestimate. HeadCount is a valid instrument for tracking heading behaviour, but may have to be calibrated in women.

Parameter study for child injury mitigation in near-side impacts through FE simulations.

Science.gov (United States)

Andersson, Marianne; Pipkorn, Bengt; Lövsund, Per

2012-01-01

The objective of this study is to investigate the effects of crash-related car parameters on head and chest injury measures for 3- and 12-year-old children in near-side impacts. The evaluation was made using a model of a complete passenger car that was impacted laterally by a barrier. The car model was validated in 2 crash conditions: the Insurance Institute for Highway Safety (IIHS) and the US New Car Assessment Program (NCAP) side impact tests. The Small Side Impact Dummy (SID-IIs) and the human body model 3 (HBM3) (Total HUman Model for Safety [THUMS] 3-year-old) finite element models were used for the parametric investigation (HBM3 on a booster). The car parameters were as follows: vehicle mass, side impact structure stiffness, a head air bag, a thorax-pelvis air bag, and a seat belt with pretensioner. The studied dependent variables were as follows: resultant head linear acceleration, resultant head rotational acceleration, chest viscous criterion, rib deflection, and relative velocity at head impact. The chest measurements were only considered for the SID-IIs. The head air bag had the greatest effect on the head measurements for both of the occupant models. On average, it reduced the peak head linear acceleration by 54 g for the HBM3 and 78 g for the SID-IIs. The seat belt had the second greatest effect on the head measurements; the peak head linear accelerations were reduced on average by 39 g (HBM3) and 44 g (SID-IIs). The high stiffness side structure increased the SID-IIs' head acceleration, whereas it had marginal effect on the HBM3. The vehicle mass had a marginal effect on SID-IIs' head accelerations, whereas the lower vehicle mass caused 18 g higher head acceleration for HBM3 and the greatest rotational acceleration. The thorax-pelvis air bag, vehicle mass, and seat belt pretensioner affected the chest measurements the most. The presence of a thorax-pelvis air bag, high vehicle mass, and a seat belt pretensioner all reduced the chest viscous criterion

Intracranial Pressure Response to Non-Penetrating Ballistic Impact: An Experimental Study Using a Pig Physical Head Model and Live Pigs

Science.gov (United States)

Liu, Hai; Kang, Jianyi; Chen, Jing; Li, Guanhua; Li, Xiaoxia; Wang, Jianmin

2012-01-01

This study was conducted to characterize the intracranial pressure response to non-penetrating ballistic impact using a "scalp-skull-brain" pig physical head model and live pigs. Forty-eight ballistic tests targeting the physical head model and anesthetized pigs protected by aramid plates were conducted with standard 9 mm bullets at low (279-297 m/s), moderate (350-372 m/s), and high (409-436 m/s) velocities. Intracranial pressure responses were recorded with pressure sensors embedded in similar brain locations in the physical head model and the anesthetized pigs. Three parameters of intracranial pressure were determined from the measured data: intracranial maximum pressure (Pmax), intracranial maximum pressure impulse (PImax), and the duration of the first positive phase (PPD). The intracranial pressure waves exhibited blast-like characteristics for both the physical model and l live pigs. Of all three parameters, Pmax is most sensitive to impact velocity, with means of 126 kPa (219 kPa), 178 kPa (474 kPa), and 241 kPa (751 kPa) for the physical model (live pigs) for low, moderate, and high impact velocities, respectively. The mean PPD becomes increasingly short as the impact velocity increases, whereas PImax shows the opposite trend. Although the pressure parameters of the physical model were much lower than those of the live pigs, good correlations between the physical model and the live pigs for the three pressure parameters, especially Pmax, were found using linear regression. This investigation suggests that Pmax is a preferred parameter for predicting the severity of the brain injury resulting from behind armor blunt trauma (BABT). PMID:23055817

The impact of Chinese cultural values on Taiwan nursing leadership styles: comparing the self-assessments of staff nurses and head nurses.

Science.gov (United States)

Chang, Yuanmay

2008-06-01

The purpose of this study was to investigate the influence of Chinese culture on nursing leadership behavior in Taiwan nurses. A descriptive study compared staff nurses' assessment of Chinese value in the leadership behavior of their head nurses. Data analysis was made on a convenience sample in Taiwan of 214 head nurses and 2,127 staff nurses who had worked with their head nurse for at least one year. Six medical centers and regional hospitals in northern (Taipei), central (Taichung) and southern (Kaohsiung) Taiwan were recruited for this study. Instruments included the demographic questionnaire, Chinese Value Survey, and Kang's Chinese Leadership Behaviors Module Scale. Results indicated that head nurses scored significantly higher than staff nurses in terms of all cultural values and leadership behaviors. Both staff nurses and head nurses scored the highest mean scores in personal integrity (Yi) and human connectedness (Ren) and the lowest in moral discipline (Li). Staff nurse perceptions of leadership behavior indicated the role of parent to be higher than either the role of director or mentor. Head nurses perceptions of leadership behavior emphasized the role of the director more than either parent or mentor. There were no significant differences between the staff nurses and head nurses in terms of expectative leadership behavior, which gave the role of director higher mean scores than those of either the parent or mentor. Positive and significant associations (r = .266 to r = .334) were found between cultural values and perceptions of leadership behavior. Cultural values predicted 10.6% of leadership behavior variance. The three demographic characteristics of location in northern Taiwan (beta = .09), intention to leave (beta = -.14), and general unit (beta = .10) and the two cultural values of human connectedness (Ren) (beta = .16) and personal integrity (Yi) (beta = .16) together reported a cumulative R2 of 14.6% to explain variance in leadership behavior

Modelling and assessment of the electric field strength caused by mobile phone to the human head.

Science.gov (United States)

Buckus, Raimondas; Strukcinskiene, Birute; Raistenskis, Juozas; Stukas, Rimantas

2016-06-01

Electromagnetic field exposure is the one of the most important physical agents that actively affects live organisms and environment. Active use of mobile phones influences the increase of electromagnetic field radiation. The aim of the study was to measure and assess the electric field strength caused by mobile phones to the human head. In this paper the software "COMSOL Multiphysics" was used to establish the electric field strength created by mobile phones around the head. The second generation (2G) Global System for Mobile (GSM) phones that operate in the frequency band of 900 MHz and reach the power of 2 W have a stronger electric field than (2G) GSM mobile phones that operate in the higher frequency band of 1,800 MHz and reach the power up to 1 W during conversation. The third generation of (3G) UMTS smart phones that effectively use high (2,100 MHz) radio frequency band emit the smallest electric field strength values during conversation. The highest electric field strength created by mobile phones is around the ear, i.e. the mobile phone location. The strength of mobile phone electric field on the phantom head decreases exponentially while moving sidewards from the center of the effect zone (the ear), and constitutes 1-12% of the artificial head's surface. The highest electric field strength values of mobile phones are associated with their higher power, bigger specific energy absorption rate (SAR) and lower frequency of mobile phone. The stronger electric field emitted by the more powerful mobile phones takes a higher percentage of the head surface. The highest electric field strength created by mobile phones is distributed over the user's ear.

Understanding Edward Muybridge: historical review of behavioral alterations after a 19th-century head injury and their multifactorial influence on human life and culture.

Science.gov (United States)

Manjila, Sunil; Singh, Gagandeep; Alkhachroum, Ayham M; Ramos-Estebanez, Ciro

2015-07-01

Edward Muybridge was an Anglo-American photographer, well known for his pioneering contributions in photography and his invention of the "zoopraxiscope," a forerunner of motion pictures. However, this 19th-century genius, with two original patents in photographic technology, made outstanding contributions in art and neurology alike, the latter being seldom acknowledged. A head injury that he sustained changed his behavior and artistic expression. The shift of his interests from animal motion photography to human locomotion and gait remains a pivotal milestone in our understanding of patterns in biomechanics and clinical neurology, while his own behavioral patterns, owing to an injury to the orbitofrontal cortex, remain a mystery even for cognitive neurologists. The behavioral changes he exhibited and the legal conundrum that followed, including a murder of which he was acquitted, all depict the complexities of his personality and impact of frontal lobe injuries. This article highlights the life journey of Muybridge, drawing parallels with Phineas Gage, whose penetrating head injury has been studied widely. The wide sojourn of Muybridge also illustrates the strong connections that he maintained with Stanford and Pennsylvania universities, which were later considered pinnacles of higher education on the two coasts of the United States.

Cumulative human impacts on marine predators

DEFF Research Database (Denmark)

Maxwell, Sara M; Hazen, Elliott L; Bograd, Steven J

2013-01-01

Stressors associated with human activities interact in complex ways to affect marine ecosystems, yet we lack spatially explicit assessments of cumulative impacts on ecologically and economically key components such as marine predators. Here we develop a metric of cumulative utilization and impact...

Highly preserved consensus gene modules in human papilloma virus 16 positive cervical cancer and head and neck cancers.

Science.gov (United States)

Zhang, Xianglan; Cha, In-Ho; Kim, Ki-Yeol

2017-12-26

In this study, we investigated the consensus gene modules in head and neck cancer (HNC) and cervical cancer (CC). We used a publicly available gene expression dataset, GSE6791, which included 42 HNC, 14 normal head and neck, 20 CC and 8 normal cervical tissue samples. To exclude bias because of different human papilloma virus (HPV) types, we analyzed HPV16-positive samples only. We identified 3824 genes common to HNC and CC samples. Among these, 977 genes showed high connectivity and were used to construct consensus modules. We demonstrated eight consensus gene modules for HNC and CC using the dissimilarity measure and average linkage hierarchical clustering methods. These consensus modules included genes with significant biological functions, including ATP binding and extracellular exosome. Eigengen network analysis revealed the consensus modules were highly preserved with high connectivity. These findings demonstrate that HPV16-positive head and neck and cervical cancers share highly preserved consensus gene modules with common potentially therapeutic targets.

Health Impacts from Human Interaction with the Environment

Science.gov (United States)

Hasan, S. E.

2008-12-01

Humans have produced far greater impact on the environment than any other living form. The impact has been so significant-particularly during the past 50 years-that a new word, Anthrposphere has started appearing in recent literature. It is now being used along with the four major components of the system earth to underscore humans' influence on the environment. Human activities have produced a myriad of impacts on the environment that span the scale from local to global. The slow process that brought humanity to the present environmental crisis began with the Industrial Revolution and has greatly accelerated since the World War II. The past 50 years mark a unique period in human history that is characterized by rapid technological advances and unprecedented population growth. While the use of technology has been very effective in meeting the needs of the growing population, it has also produced serious impact on the environment. Large scale exploitation of mineral, fuel, water, forest, and marine resources has led to severe environmental degradation; and the resulting pollution of air, water, and land has caused serious consequences to human and ecological health. The presentation deals with the adverse impact on human health associated with mining, dam and reservoir construction, improper waste management, use of fossil fuels, and climate change. Case studies are included to illustrate health impacts from metal and coal mining; dam and reservoir construction and preponderance of disease vectors; pollution caused by improper waste disposal and the resulting incidence of cancer and other diseases; and emergence of vector-borne diseases at hitherto unknown locations, cardiovascular and respiratory track ailments, and increased morbidity and mortality triggered by elevated temperatures associated with climate change. A brief discussion of possible measures to mitigate the health consequences is also included in the presentation.

A three dimensional children head database for acoustical research and development

DEFF Research Database (Denmark)

Harder, Stine; Paulsen, Rasmus Reinhold; Larsen, Martin

2013-01-01

Most computational-acoustic work within spatial hearing relies on head-related transfer functions from databases of measurements taken on adult humans or dummy heads. We aim to provide a set of 3D digital heads including children, from which head-related transfer functions can be computed instead...

Assessing human rights impacts in corporate development projects

Energy Technology Data Exchange (ETDEWEB)

Salcito, Kendyl, E-mail: kendyl.salcito@unibas.ch [Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, P.O. Box, CH-4002 Basel (Switzerland); University of Basel, P.O. Box, CH-4003 Basel (Switzerland); NomoGaia, 1900 Wazee Street, Suite 303, Denver, CO 80202 (United States); NewFields, LLC, Denver, CO 80202 (United States); Utzinger, Jürg, E-mail: juerg.utzinger@unibas.ch [Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, P.O. Box, CH-4002 Basel (Switzerland); University of Basel, P.O. Box, CH-4003 Basel (Switzerland); Weiss, Mitchell G., E-mail: Mitchell-g.Weiss@unibas.ch [Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, P.O. Box, CH-4002 Basel (Switzerland); University of Basel, P.O. Box, CH-4003 Basel (Switzerland); Münch, Anna K., E-mail: annak.muench@gmail.com [Emerging Pathogens Institute, University of Florida, Gainesville, FL 32610 (United States); Singer, Burton H., E-mail: bhsinger@epi.ufl.edu [Emerging Pathogens Institute, University of Florida, Gainesville, FL 32610 (United States); Krieger, Gary R., E-mail: gkrieger@newfields.com [NewFields, LLC, Denver, CO 80202 (United States); Wielga, Mark, E-mail: wielga@nomogaia.org [NomoGaia, 1900 Wazee Street, Suite 303, Denver, CO 80202 (United States); NewFields, LLC, Denver, CO 80202 (United States)

2013-09-15

Human rights impact assessment (HRIA) is a process for systematically identifying, predicting and responding to the potential impact on human rights of a business operation, capital project, government policy or trade agreement. Traditionally, it has been conducted as a desktop exercise to predict the effects of trade agreements and government policies on individuals and communities. In line with a growing call for multinational corporations to ensure they do not violate human rights in their activities, HRIA is increasingly incorporated into the standard suite of corporate development project impact assessments. In this context, the policy world's non-structured, desk-based approaches to HRIA are insufficient. Although a number of corporations have commissioned and conducted HRIA, no broadly accepted and validated assessment tool is currently available. The lack of standardisation has complicated efforts to evaluate the effectiveness of HRIA as a risk mitigation tool, and has caused confusion in the corporate world regarding company duties. Hence, clarification is needed. The objectives of this paper are (i) to describe an HRIA methodology, (ii) to provide a rationale for its components and design, and (iii) to illustrate implementation of HRIA using the methodology in two selected corporate development projects—a uranium mine in Malawi and a tree farm in Tanzania. We found that as a prognostic tool, HRIA could examine potential positive and negative human rights impacts and provide effective recommendations for mitigation. However, longer-term monitoring revealed that recommendations were unevenly implemented, dependent on market conditions and personnel movements. This instability in the approach to human rights suggests a need for on-going monitoring and surveillance. -- Highlights: • We developed a novel methodology for corporate human rights impact assessment. • We piloted the methodology on two corporate projects—a mine and a plantation. �

Assessing human rights impacts in corporate development projects

International Nuclear Information System (INIS)

Salcito, Kendyl; Utzinger, Jürg; Weiss, Mitchell G.; Münch, Anna K.; Singer, Burton H.; Krieger, Gary R.; Wielga, Mark

2013-01-01

Human rights impact assessment (HRIA) is a process for systematically identifying, predicting and responding to the potential impact on human rights of a business operation, capital project, government policy or trade agreement. Traditionally, it has been conducted as a desktop exercise to predict the effects of trade agreements and government policies on individuals and communities. In line with a growing call for multinational corporations to ensure they do not violate human rights in their activities, HRIA is increasingly incorporated into the standard suite of corporate development project impact assessments. In this context, the policy world's non-structured, desk-based approaches to HRIA are insufficient. Although a number of corporations have commissioned and conducted HRIA, no broadly accepted and validated assessment tool is currently available. The lack of standardisation has complicated efforts to evaluate the effectiveness of HRIA as a risk mitigation tool, and has caused confusion in the corporate world regarding company duties. Hence, clarification is needed. The objectives of this paper are (i) to describe an HRIA methodology, (ii) to provide a rationale for its components and design, and (iii) to illustrate implementation of HRIA using the methodology in two selected corporate development projects—a uranium mine in Malawi and a tree farm in Tanzania. We found that as a prognostic tool, HRIA could examine potential positive and negative human rights impacts and provide effective recommendations for mitigation. However, longer-term monitoring revealed that recommendations were unevenly implemented, dependent on market conditions and personnel movements. This instability in the approach to human rights suggests a need for on-going monitoring and surveillance. -- Highlights: • We developed a novel methodology for corporate human rights impact assessment. • We piloted the methodology on two corporate projects—a mine and a plantation. • Human

Detecting Large-Scale Brain Networks Using EEG: Impact of Electrode Density, Head Modeling and Source Localization

Science.gov (United States)

Liu, Quanying; Ganzetti, Marco; Wenderoth, Nicole; Mantini, Dante

2018-01-01

Resting state networks (RSNs) in the human brain were recently detected using high-density electroencephalography (hdEEG). This was done by using an advanced analysis workflow to estimate neural signals in the cortex and to assess functional connectivity (FC) between distant cortical regions. FC analyses were conducted either using temporal (tICA) or spatial independent component analysis (sICA). Notably, EEG-RSNs obtained with sICA were very similar to RSNs retrieved with sICA from functional magnetic resonance imaging data. It still remains to be clarified, however, what technological aspects of hdEEG acquisition and analysis primarily influence this correspondence. Here we examined to what extent the detection of EEG-RSN maps by sICA depends on the electrode density, the accuracy of the head model, and the source localization algorithm employed. Our analyses revealed that the collection of EEG data using a high-density montage is crucial for RSN detection by sICA, but also the use of appropriate methods for head modeling and source localization have a substantial effect on RSN reconstruction. Overall, our results confirm the potential of hdEEG for mapping the functional architecture of the human brain, and highlight at the same time the interplay between acquisition technology and innovative solutions in data analysis. PMID:29551969

Capabilities of Helmets for Preventing Head Injuries Induced by Ballistic Impacts

Directory of Open Access Journals (Sweden)

D.V. Balandin

2004-01-01

Full Text Available The limiting performance of ballistically loaded helmets designed to reduce head injuries is studied analytically. The projectile does not penetrate the helmet. This analysis evaluates the absolute minimum of the peak displacement of the helmet shell relative to the head, provided that criteria measuring the severity of head injuries lie within prescribed limits. Rather than optimize a specific design configuration, e.g. a viscoelastic foam liner, characteristics of a time-dependent force representing the helmet liner are calculated. The formulation reduces the limiting performance analysis to an optimal control problem.

Anticipated Impact of In-Car Mobile Calls on the Electromagnetic Interaction of Handset Antenna and Human

Directory of Open Access Journals (Sweden)

Salah I. Yahya

2014-09-01

Full Text Available This paper investigates the impact of the in-car mobile call on the electromagnetic interaction of the mobile handset antenna and user’s head. This impact was evaluated from two different perspectives; First, the antenna performance, e.g., total isotropic sensitivity and total efficiency, and second, the specific absorption rate (SAR induced in the user's head. A Yee-FDTD based electromagnetic solver was used to simulate a mobile phone in hand close proximity to head at cheek and tilt positions, and working at a frequency of 1900 MHz (GSM 1900/PCS while making a call inside a car. A Specific Anthropomorphic Mannequin (SAM was used to simulate the user’s head, a generic phone was used to simulate the mobile phone, a semi-realistic model with three tissues, i.e., skin, bone and muscle, was used to simulate the user’s hand, and a CAD model of Ferrari F430-brand was used to simulate the car. The results showed a considerable degradation in the mobile phone antenna performance while making a mobile phone call inside a car that may drive the mobile phone increases its radiated power to establish a successful connection with the base-station antenna, and consequently increases the induced specific absorption rate in the user’s head.

An investigation of the effects of sports-related concussion in youth using functional magnetic resonance imaging and the head impact telemetry system.

Science.gov (United States)

Keightley, Michelle; Green, Stephanie; Reed, Nick; Agnihotri, Sabrina; Wilkinson, Amy; Lobaugh, Nancy

2011-01-12

One of the most commonly reported injuries in children who participate in sports is concussion or mild traumatic brain injury (mTBI). Children and youth involved in organized sports such as competitive hockey are nearly six times more likely to suffer a severe concussion compared to children involved in other leisure physical activities. While the most common cognitive sequelae of mTBI appear similar for children and adults, the recovery profile and breadth of consequences in children remains largely unknown, as does the influence of pre-injury characteristics (e.g. gender) and injury details (e.g. magnitude and direction of impact) on long-term outcomes. Competitive sports, such as hockey, allow the rare opportunity to utilize a pre-post design to obtain pre-injury data before concussion occurs on youth characteristics and functioning and to relate this to outcome following injury. Our primary goals are to refine pediatric concussion diagnosis and management based on research evidence that is specific to children and youth. To do this we use new, multi-modal and integrative approaches that will: 1. Evaluate the immediate effects of head trauma in youth. 2. Monitor the resolution of post-concussion symptoms (PCS) and cognitive performance during recovery. 3. Utilize new methods to verify brain injury and recovery. To achieve our goals, we have implemented the Head Impact Telemetry (HIT) System. (Simbex; Lebanon, NH, USA). This system equips commercially available Easton S9 hockey helmets (Easton-Bell Sports; Van Nuys, CA, USA) with single-axis accelerometers designed to measure real-time head accelerations during contact sport participation. By using telemetric technology, the magnitude of acceleration and location of all head impacts during sport participation can be objectively detected and recorded. We also use functional magnetic resonance imaging (fMRI) to localize and assess changes in neural activity specifically in the medial temporal and frontal lobes

Tridimensional pose estimation of a person head

International Nuclear Information System (INIS)

Perez Berenguer, Elisa; Soria, Carlos; Nasisi, Oscar; Mut, Vicente

2007-01-01

In this work, we present a method for estimating 3-D motion parameters; this method provides an alternative way for 3D head pose estimation from image sequence in the current computer vision literature. This method is robust over extended sequences and large head motions and accurately extracts the orientation angles of head from a single view. Experimental results show that this tracking system works well for development a human-computer interface for people that possess severe motor incapacity

A unified model of heading and path perception in primate MSTd.

Directory of Open Access Journals (Sweden)

Oliver W Layton

2014-02-01

Full Text Available Self-motion, steering, and obstacle avoidance during navigation in the real world require humans to travel along curved paths. Many perceptual models have been proposed that focus on heading, which specifies the direction of travel along straight paths, but not on path curvature, which humans accurately perceive and is critical to everyday locomotion. In primates, including humans, dorsal medial superior temporal area (MSTd has been implicated in heading perception. However, the majority of MSTd neurons respond optimally to spiral patterns, rather than to the radial expansion patterns associated with heading. No existing theory of curved path perception explains the neural mechanisms by which humans accurately assess path and no functional role for spiral-tuned cells has yet been proposed. Here we present a computational model that demonstrates how the continuum of observed cells (radial to circular in MSTd can simultaneously code curvature and heading across the neural population. Curvature is encoded through the spirality of the most active cell, and heading is encoded through the visuotopic location of the center of the most active cell's receptive field. Model curvature and heading errors fit those made by humans. Our model challenges the view that the function of MSTd is heading estimation, based on our analysis we claim that it is primarily concerned with trajectory estimation and the simultaneous representation of both curvature and heading. In our model, temporal dynamics afford time-history in the neural representation of optic flow, which may modulate its structure. This has far-reaching implications for the interpretation of studies that assume that optic flow is, and should be, represented as an instantaneous vector field. Our results suggest that spiral motion patterns that emerge in spatio-temporal optic flow are essential for guiding self-motion along complex trajectories, and that cells in MSTd are specifically tuned to extract

A Unified Model of Heading and Path Perception in Primate MSTd

Science.gov (United States)

Layton, Oliver W.; Browning, N. Andrew

2014-01-01

Self-motion, steering, and obstacle avoidance during navigation in the real world require humans to travel along curved paths. Many perceptual models have been proposed that focus on heading, which specifies the direction of travel along straight paths, but not on path curvature, which humans accurately perceive and is critical to everyday locomotion. In primates, including humans, dorsal medial superior temporal area (MSTd) has been implicated in heading perception. However, the majority of MSTd neurons respond optimally to spiral patterns, rather than to the radial expansion patterns associated with heading. No existing theory of curved path perception explains the neural mechanisms by which humans accurately assess path and no functional role for spiral-tuned cells has yet been proposed. Here we present a computational model that demonstrates how the continuum of observed cells (radial to circular) in MSTd can simultaneously code curvature and heading across the neural population. Curvature is encoded through the spirality of the most active cell, and heading is encoded through the visuotopic location of the center of the most active cell's receptive field. Model curvature and heading errors fit those made by humans. Our model challenges the view that the function of MSTd is heading estimation, based on our analysis we claim that it is primarily concerned with trajectory estimation and the simultaneous representation of both curvature and heading. In our model, temporal dynamics afford time-history in the neural representation of optic flow, which may modulate its structure. This has far-reaching implications for the interpretation of studies that assume that optic flow is, and should be, represented as an instantaneous vector field. Our results suggest that spiral motion patterns that emerge in spatio-temporal optic flow are essential for guiding self-motion along complex trajectories, and that cells in MSTd are specifically tuned to extract complex trajectory

Thermal effects of whole head submersion in cold water on nonshivering humans.

Science.gov (United States)

Pretorius, Thea; Bristow, Gerald K; Steinman, Alan M; Giesbrecht, Gordon G

2006-08-01

This study isolated the effect of whole head submersion in cold water, on surface heat loss and body core cooling, when the confounding effect of shivering heat production was pharmacologically eliminated. Eight healthy male subjects were studied in 17 degrees C water under four conditions: the body was either insulated or uninsulated, with the head either above the water or completely submersed in each body-insulation subcondition. Shivering was abolished with buspirone (30 mg) and meperidine (2.5 mg/kg), and subjects breathed compressed air throughout all trials. Over the first 30 min of immersion, exposure of the head increased core cooling both in the body-insulated conditions (head out: 0.47 +/- 0.2 degrees C, head in: 0.77 +/- 0.2 degrees C; P body-exposed conditions (head out: 0.84 +/- 0.2 degrees C and head in: 1.17 +/- 0.5 degrees C; P body surface area) in the body-exposed conditions increased total heat loss by only 10%. In both body-exposed and body-insulated conditions, head submersion increased core cooling rate much more (average of 42%) than it increased total heat loss. This may be explained by a redistribution of blood flow in response to stimulation of thermosensitive and/or trigeminal receptors in the scalp, neck and face, where a given amount of heat loss would have a greater cooling effect on a smaller perfused body mass. In 17 degrees C water, the head does not contribute relatively more than the rest of the body to surface heat loss; however, a cold-induced reduction of perfused body mass may allow this small increase in heat loss to cause a relatively larger cooling of the body core.

Simplified realistic human head model for simulating Tumor Treating Fields (TTFields).

Science.gov (United States)

Wenger, Cornelia; Bomzon, Ze'ev; Salvador, Ricardo; Basser, Peter J; Miranda, Pedro C

2016-08-01

Tumor Treating Fields (TTFields) are alternating electric fields in the intermediate frequency range (100-300 kHz) of low-intensity (1-3 V/cm). TTFields are an anti-mitotic treatment against solid tumors, which are approved for Glioblastoma Multiforme (GBM) patients. These electric fields are induced non-invasively by transducer arrays placed directly on the patient's scalp. Cell culture experiments showed that treatment efficacy is dependent on the induced field intensity. In clinical practice, a software called NovoTalTM uses head measurements to estimate the optimal array placement to maximize the electric field delivery to the tumor. Computational studies predict an increase in the tumor's electric field strength when adapting transducer arrays to its location. Ideally, a personalized head model could be created for each patient, to calculate the electric field distribution for the specific situation. Thus, the optimal transducer layout could be inferred from field calculation rather than distance measurements. Nonetheless, creating realistic head models of patients is time-consuming and often needs user interaction, because automated image segmentation is prone to failure. This study presents a first approach to creating simplified head models consisting of convex hulls of the tissue layers. The model is able to account for anisotropic conductivity in the cortical tissues by using a tensor representation estimated from Diffusion Tensor Imaging. The induced electric field distribution is compared in the simplified and realistic head models. The average field intensities in the brain and tumor are generally slightly higher in the realistic head model, with a maximal ratio of 114% for a simplified model with reasonable layer thicknesses. Thus, the present pipeline is a fast and efficient means towards personalized head models with less complexity involved in characterizing tissue interfaces, while enabling accurate predictions of electric field distribution.

Effects of cooling portions of the head on human thermoregulatory response.

Science.gov (United States)

Katsuura, T; Tomioka, K; Harada, H; Iwanaga, K; Kikuchi, Y

1996-03-01

Seven healthy young male students participated in this study. Each subject sat on a chair in an anteroom at 25 degrees C for 30 min and then entered a climatic chamber, controlled at 40 degrees C and R.H. 50%, and sat on a chair for 90 min. Cooling of frontal portion including the region around the eyes (FC), occipital portion (OC), and temporal portion (TC) began after 50 min of entering. An experiment without head cooling (NC) was also made for the control measurement. Thermal comfort and thermal sensation were improved by head cooling, but response was the same regardless of portion cooled. Although rectal temperature, mean skin temperature and heart rate showed no significant effect due to head cooling, forearm skin blood flow (FBF), sweat rate (SR), and body weight loss (delta Wt) had a tendency to be depressed. FBF in FC and TC decreased during head cooling, but that in OC and NC did not change significantly, while SR in FC was depressed. delta Wt showed total sweating to decrease by FC and TC, and FC to have greater inhibitory effect on sweating than OC. Thermal strain was evaluated by the modified Craig Index (I(s)). I(s) in FC decreased significantly more than in NC. Cooling of other portions of the head had no significant effect on I(s). Cooling of the frontal portion of the head may thus be concluded to have the most effect on thermoregulatory response in a hot environment.

Motion control of the Twente humanoid head

NARCIS (Netherlands)

Visser, L.C.; Carloni, Raffaella; Stramigioli, Stefano

2009-01-01

In this work, we present the design and the realization of the motion control algorithm implemented in the Twente hu- manoid head, a seven degrees of freedom (dof) robotic sys- tem. The aim of the project is to have a humanoid head that can serve as a research platform for human-machine interac-

The role of human papilloma virus and p16 in occult primary of the head and neck: a comprehensive review of the literature.

Science.gov (United States)

Fotopoulos, George; Pavlidis, Nicholas

2015-02-01

Cancer of unknown primary of the head and neck is a challenging entity for the oncologist. The role of human papilloma virus/p16 in carcinogenesis and in prognosis is well established in certain HNSCC especially in that of the oropharynx. In the case of occult primary of the head and neck the role of HPV/p16 positivity is not well defined regarding prognosis and localization of the primary. An independent review of PubMed and ScienceDirect database was performed up to May 2014 using combinations of terms such as "occult primary of the head and neck", "CUP of the head and neck" "metastatic cervical squamous cell carcinoma of unknown primary", "HPV" and "HPV and head and neck cancer". Literature review shows a strong association between HPV/p16 positivity and primary location in the oropharynx in patients with CUP of the head and neck as well as a better clinical outcome. HPV positivity and p16 overexpression could be used as surrogate markers in the search of the primary site of patients with CUP of the head and neck therefore maybe guiding treatment decisions. Copyright © 2014 Elsevier Ltd. All rights reserved.

Introduction of the Canadian CT Head Rule Reduces CT Scan Use ...

African Journals Online (AJOL)

amnesia or witnessed disorientation in a patient with a GCS score of 13–15 who has suffered a traumatic event, the evaluation of minor head injury using. Computerized Axial Tomography Scan of the Head. (CT-head) has remained controversial.(1,3). CT–head is expensive, time consuming, strenuous to human resource ...

Pigeons (C. livia Follow Their Head during Turning Flight: Head Stabilization Underlies the Visual Control of Flight

Directory of Open Access Journals (Sweden)

Ivo G. Ros

2017-12-01

Full Text Available Similar flight control principles operate across insect and vertebrate fliers. These principles indicate that robust solutions have evolved to meet complex behavioral challenges. Following from studies of visual and cervical feedback control of flight in insects, we investigate the role of head stabilization in providing feedback cues for controlling turning flight in pigeons. Based on previous observations that the eyes of pigeons remain at relatively fixed orientations within the head during flight, we test potential sensory control inputs derived from head and body movements during 90° aerial turns. We observe that periods of angular head stabilization alternate with rapid head repositioning movements (head saccades, and confirm that control of head motion is decoupled from aerodynamic and inertial forces acting on the bird's continuously rotating body during turning flapping flight. Visual cues inferred from head saccades correlate with changes in flight trajectory; whereas the magnitude of neck bending predicts angular changes in body position. The control of head motion to stabilize a pigeon's gaze may therefore facilitate extraction of important motion cues, in addition to offering mechanisms for controlling body and wing movements. Strong similarities between the sensory flight control of birds and insects may also inspire novel designs of robust controllers for human-engineered autonomous aerial vehicles.

Absorbed dose estimates to structures of the brain and head using a high-resolution voxel-based head phantom

International Nuclear Information System (INIS)

Evans, Jeffrey F.; Blue, Thomas E.; Gupta, Nilendu

2001-01-01

The purpose of this article is to demonstrate the viability of using a high-resolution 3-D head phantom in Monte Carlo N-Particle (MCNP) for boron neutron capture therapy (BNCT) structure dosimetry. This work describes a high-resolution voxel-based model of a human head and its use for calculating absorbed doses to the structures of the brain. The Zubal head phantom is a 3-D model of a human head that can be displayed and manipulated on a computer. Several changes were made to the original head phantom which now contains over 29 critical structures of the brain and head. The modified phantom is a 85x109x120 lattice of voxels, where each voxel is 2.2x2.2x1.4 mm 3 . This model was translated into MCNP lattice format. As a proof of principle study, two MCNP absorbed dose calculations were made (left and right lateral irradiations) using a uniformly distributed neutron disk source with an 1/E energy spectrum. Additionally, the results of these two calculations were combined to estimate the absorbed doses from a bilateral irradiation. Radiobiologically equivalent (RBE) doses were calculated for all structures and were normalized to 12.8 Gy-Eq. For a left lateral irradiation, the left motor cortex receives the limiting RBE dose. For a bilateral irradiation, the insula cortices receive the limiting dose. Among the nonencephalic structures, the parotid glands receive RBE doses that were within 15% of the limiting dose

Simulation of Cardiovascular Response to the Head-Up/Head-Down Tilt at Different Angles

Science.gov (United States)

Liu, Yang; Lu, Hong-Bing; Jiao, Chun; Zhang, Li-Fan

2008-06-01

The disappearance of hydrostatic pressure is the original factor that causes the changes of cardiovascular system under microgravity. The hydrostatical changes can be simulated by postural changes. Especially the head-down position can be used to simulate the effects of microgravity. The goal of this investigation was to develop a mathematical model for simulation of the human cardiovascular responses to acute and prolonged exposure under microgravity environment. We were particularly interested in the redistribution of transmural pressures, flows, blood volume, and the consequent alterations in local hemodynamics in different cardiovascular compartments during acute exposure and chronic adjustments. As a preliminary study, we first developed a multi-element, distributed hemodynamic model of human cardiovascular system, and verified the model to simulate cardiovascular changes during head up/down tilt at various angles.

Virtual impact: visualizing the potential effects of cosmic impact in human history

Energy Technology Data Exchange (ETDEWEB)

Masse, W Bruce [Los Alamos National Laboratory; Janecky, David R [Los Alamos National Laboratory; Forte, Maurizio [UC MERCED; Barrientos, Gustavo [UNIV OF LA PLATA, ARG.

2009-01-01

Current models indicate that catastrophic impacts by asteroids and comets capable of killing more than one quarter of Earth's human population have occurred on average once every million years; smaller impacts, such the 1908 Tunguska impact that leveled more than 2,000 square km of Siberian forest, occur every 200-300 years. Therefore, cosmic impact likely significantly affected hominine evolution and conceivably played a role in Holocene period human culture history. Regrettably, few archaeologists are trained to appreciate the nature and potential effects of cosmic impact. We have developed a conceptual model for an extensible set of educational and research tools based on virtual reality collaborative environments to engage archaeologists and the general public on the topic of the role of cosmic impact in human history. Our initial focus is on two documented asteroid impacts in Argentina during the period of 4000 to 1000 B.C. Campo del Cicio resulted in an energy release of around 2-3 megatons (100-150 times the Hiroshima atomic weapon), and left several craters and a strewn field covering 493 km{sup 2} in northeastern Argentina. Rio Cuarto was likely more than 1000 megatons and may have devastated an area greater than 50,000 km{sup 2} in central Argentina. We are focusing on reconstructions of these events and their potential effects on contemporary hunter and gatherers. Our vinual reality tools also introduce interactive variables (e.g., impactor physical properties, climate, vegetation, topography, and social complexity) to allow researchers and students to better investigate and evaluate the factors that significantly influence cosmic impact effects.

A miniature shoe-mounted orientation determination system for accurate indoor heading and trajectory tracking.

Science.gov (United States)

Zhang, Shengzhi; Yu, Shuai; Liu, Chaojun; Liu, Sheng

2016-06-01

Tracking the position of pedestrian is urgently demanded when the most commonly used GPS (Global Position System) is unavailable. Benefited from the small size, low-power consumption, and relatively high reliability, micro-electro-mechanical system sensors are well suited for GPS-denied indoor pedestrian heading estimation. In this paper, a real-time miniature orientation determination system (MODS) was developed for indoor heading and trajectory tracking based on a novel dual-linear Kalman filter. The proposed filter precludes the impact of geomagnetic distortions on pitch and roll that the heading is subjected to. A robust calibration approach was designed to improve the accuracy of sensors measurements based on a unified sensor model. Online tests were performed on the MODS with an improved turntable. The results demonstrate that the average RMSE (root-mean-square error) of heading estimation is less than 1°. Indoor heading experiments were carried out with the MODS mounted on the shoe of pedestrian. Besides, we integrated the existing MODS into an indoor pedestrian dead reckoning application as an example of its utility in realistic actions. A human attitude-based walking model was developed to calculate the walking distance. Test results indicate that mean percentage error of indoor trajectory tracking achieves 2% of the total walking distance. This paper provides a feasible alternative for accurate indoor heading and trajectory tracking.

Concept of waste and its impact on human health.

Science.gov (United States)

Pashkov, Vitalii M; Batyhina, Olena M; Trotska, Maryna V

Impact of the environment on human health is increasingly being paid attention both at the international level and at the level of individual countries. Among the factors that anyhow can affect it negatively, various objects are distinguished and waste is not of the last consequence. It has different nature of origin, ways of further utilization and a degree of impact on human health and the environment. Its generation, utilization and neutralization are determined by the relevant processes; their research allows continuous improvement and reduction of their negative impact on human health and the environment. To analyze provisions of the international legislation concerning the concept of waste and its classification, as well as its potential impacts on human health and the environment. The study analyzes and uses international legal documents, data of international organizations and scientists' deductions. Furthermore, the study integrates information from scientific journals with scientific methods from the medical and legal point of view. Within the framework of the system approach, as well as analysis and synthesis, the concept of waste, its classification and impact on human health and the environment have been researched. In consequence of the conducted study, it has been found that at the European level, considerable attention is paid to waste in the context of its possible negative impact on human health and the environment. Solution of this problem is carried out with the integrated approach, which is expressed both in enacting statutory acts and amending existing ones, as well as elucidating various aspects at the scientific, methodological, statistical and other levels. Waste in itself has different nature of origin, negative impact, ways of its further utilization. Some kinds of it can be used further in order to achieve other goals and needs that are not related to their generation, others can no longer be used for human benefits taking into account

Sex Differences in Anthropometrics and Heading Kinematics Among Division I Soccer Athletes.

Science.gov (United States)

Bretzin, Abigail C; Mansell, Jamie L; Tierney, Ryan T; McDevitt, Jane K

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. The relationship between anthropometrics and soccer heading kinematics will not differ between sexes. The relationship between anthropometrics and soccer heading kinematics will not differ between ball speeds. Pilot, cross-sectional design. Level 3. Division I soccer athletes (5 male, 8 female) were assessed for head-neck anthropometric and neck strength measurements in 6 directions (ie, flexion, extension, right and left lateral flexions and rotations). Participants headed the ball 10 times (25 or 40 mph) while wearing an accelerometer secured to their head. Kinematic measurements (ie, linear acceleration and rotational velocity) were recorded at 2 ball speeds. Sex differences were observed in neck girth ( t = 5.09, P soccer heading kinematics for sex and ball speeds. Neck girth and neck strength are factors that may limit head impact kinematics.

Effects of face/head and whole body cooling during passive heat stress on human somatosensory processing.

Science.gov (United States)

Nakata, Hiroki; Namba, Mari; Kakigi, Ryusuke; Shibasaki, Manabu

2017-06-01

We herein investigated the effects of face/head and whole body cooling during passive heat stress on human somatosensory processing recorded by somatosensory-evoked potentials (SEPs) at C4' and Fz electrodes. Fourteen healthy subjects received a median nerve stimulation at the left wrist. SEPs were recorded at normothermic baseline (Rest), when esophageal temperature had increased by ~1.2°C (heat stress: HS) during passive heating, face/head cooling during passive heating (face/head cooling: FHC), and after HS (whole body cooling: WBC). The latencies and amplitudes of P14, N20, P25, N35, P45, and N60 at C4' and P14, N18, P22, and N30 at Fz were evaluated. Latency indicated speed of the subcortical and cortical somatosensory processing, while amplitude reflected the strength of neural activity. Blood flow in the internal and common carotid arteries (ICA and CCA, respectively) and psychological comfort were recorded in each session. Increases in esophageal temperature due to HS significantly decreased the amplitude of N60, psychological comfort, and ICA blood flow in the HS session, and also shortened the latencies of SEPs (all, P body temperature. Copyright © 2017 the American Physiological Society.

A Novel Method for Intraoral Access to the Superior Head of the Human Lateral Pterygoid Muscle

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Aleli Tôrres Oliveira

2014-01-01

Full Text Available Background. The uncoordinated activity of the superior and inferior parts of the lateral pterygoid muscle (LPM has been suggested to be one of the causes of temporomandibular joint (TMJ disc displacement. A therapy for this muscle disorder is the injection of botulinum toxin (BTX, of the LPM. However, there is a potential risk of side effects with the injection guide methods currently available. In addition, they do not permit appropriate differentiation between the two bellies of the muscle. Herein, a novel method is presented to provide intraoral access to the superior head of the human LPM with maximal control and minimal hazards. Methods. Computational tomography along with digital imaging software programs and rapid prototyping techniques were used to create a rapid prototyped guide to orient BTX injections in the superior LPM. Results. The method proved to be feasible and reliable. Furthermore, when tested in one volunteer it allowed precise access to the upper head of LPM, without producing side effects. Conclusions. The prototyped guide presented in this paper is a novel tool that provides intraoral access to the superior head of the LPM. Further studies will be necessary to test the efficacy and validate this method in a larger cohort of subjects.

Evidence for Acute Electrophysiological and Cognitive Changes Following Routine Soccer Heading

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Thomas G. Di Virgilio

2016-11-01

Discussion: Sub-concussive head impacts routine in soccer heading are associated with immediate, measurable electrophysiological and cognitive impairments. Although these changes in brain function were transient, these effects may signal direct consequences of routine soccer heading on (long-term brain health which requires further study.

Robust human body model injury prediction in simulated side impact crashes.

Science.gov (United States)

Golman, Adam J; Danelson, Kerry A; Stitzel, Joel D

2016-01-01

This study developed a parametric methodology to robustly predict occupant injuries sustained in real-world crashes using a finite element (FE) human body model (HBM). One hundred and twenty near-side impact motor vehicle crashes were simulated over a range of parameters using a Toyota RAV4 (bullet vehicle), Ford Taurus (struck vehicle) FE models and a validated human body model (HBM) Total HUman Model for Safety (THUMS). Three bullet vehicle crash parameters (speed, location and angle) and two occupant parameters (seat position and age) were varied using a Latin hypercube design of Experiments. Four injury metrics (head injury criterion, half deflection, thoracic trauma index and pelvic force) were used to calculate injury risk. Rib fracture prediction and lung strain metrics were also analysed. As hypothesized, bullet speed had the greatest effect on each injury measure. Injury risk was reduced when bullet location was further from the B-pillar or when the bullet angle was more oblique. Age had strong correlation to rib fractures frequency and lung strain severity. The injuries from a real-world crash were predicted using two different methods by (1) subsampling the injury predictors from the 12 best crush profile matching simulations and (2) using regression models. Both injury prediction methods successfully predicted the case occupant's low risk for pelvic injury, high risk for thoracic injury, rib fractures and high lung strains with tight confidence intervals. This parametric methodology was successfully used to explore crash parameter interactions and to robustly predict real-world injuries.

Parental Book Reading and Social-Emotional Outcomes for Head Start Children in Foster Care.

Science.gov (United States)

Lee, Kyunghee; Lee, Jung-Sook

2016-01-01

This study examines the associations between parental book reading and social-emotional outcomes for Head Start children in foster care. Despite no main Head Start impact on parental book reading, subgroup effects were found. Foster parents in Head Start provided more book reading for children with disabilities but less for children with low preacademic scores. Head Start enhanced social-emotional outcomes for children in foster care. The positive impacts of Head Start on children's social-emotional outcomes were greater when parents read books frequently. Head Start should include more foster families and provided parenting skills to enhance social-emotional outcomes for children in foster care.

Does Head Start differentially benefit children with risks targeted by the program’s service model?☆

Science.gov (United States)

Miller, Elizabeth B.; Farkas, George; Duncan, Greg J.

2015-01-01

Data from the Head Start Impact Study (N = 3540) were used to test for differential benefits of Head Start after one program year and after kindergarten on pre-academic and behavior outcomes for children at risk in the domains targeted by the program’s comprehensive services. Although random assignment to Head Start produced positive treatment main effects on children’s pre-academic skills and behavior problems, residualized growth models showed that random assignment to Head Start did not differentially benefit the pre-academic skills of children with risk factors targeted by the Head Start service model. The models showed detrimental impacts of Head Start for maternal-reported behavior problems of high-risk children, but slightly more positive impacts for teacher-reported behavior. Policy implications for Head Start are discussed. PMID:26379369

Oral sex and human papilloma virus-related head and neck squamous cell cancer: a review of the literature.

Science.gov (United States)

Shah, Ankit; Malik, Akshat; Garg, Apurva; Mair, Manish; Nair, Sudhir; Chaturvedi, Pankaj

2017-11-01

Head neck squamous cell carcinomas (HNSCCs) are a significant cause of morbidity and mortality all around the world. Just like tobacco and alcohol, Human papilloma virus (HPV) infection is now recognized to play a role in the pathogenesis of a subset of HNSCCs. Unprotected sexual behaviours with the HPV carrier plays an important role in transmission of this virus. The global incidence of head and neck cancers is declining, but the incidence of HPV related head and neck cancers is rapidly increasing over the last few decades. However, most institutions do not mandate documentation of sexual history or counselling of patients regarding sexual practices like they do for tobacco and alcohol addictions in HNSCC patients. The aim of this review of literature is to analyse if there is a strong evidence to correlate oral sex with HPV related HNSCC and counsel the patient's regarding sexual behaviours. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Impacts of “metals” on human health: uncertainties in using different Life Cycle Impact Assessment (LCIA) methodologies

DEFF Research Database (Denmark)

Pizzol, Massimo; Christensen, Per; Schmidt, Jannick Højrup

This study looks into the uncertainties in determining the impact of “metals” emissions to human health, in Life Cycle Impact Assessment (LCIA). Metals are diverse substances, with different proprieties and characteristics, considered important in LCIA because of their toxicity to humans or ecosy......This study looks into the uncertainties in determining the impact of “metals” emissions to human health, in Life Cycle Impact Assessment (LCIA). Metals are diverse substances, with different proprieties and characteristics, considered important in LCIA because of their toxicity to humans...... be considered in an impact assessment focused on human health, and defined a list of 14 metals. We performed a contribution analysis in order to compare methods in relative terms; an approach successfully used in other studies. Various processes have been analyzed with 8 different LCIA methods in order...... to assess both how much each metal contributes to the total impact on human health, when only metal emissions are present, and how much metals in total contribute when also other toxic substances are included in the inventory of emissions. Differences between the methods are great and due...

A video, text, and speech-driven realistic 3-d virtual head for human-machine interface.

Science.gov (United States)

Yu, Jun; Wang, Zeng-Fu

2015-05-01

A multiple inputs-driven realistic facial animation system based on 3-D virtual head for human-machine interface is proposed. The system can be driven independently by video, text, and speech, thus can interact with humans through diverse interfaces. The combination of parameterized model and muscular model is used to obtain a tradeoff between computational efficiency and high realism of 3-D facial animation. The online appearance model is used to track 3-D facial motion from video in the framework of particle filtering, and multiple measurements, i.e., pixel color value of input image and Gabor wavelet coefficient of illumination ratio image, are infused to reduce the influence of lighting and person dependence for the construction of online appearance model. The tri-phone model is used to reduce the computational consumption of visual co-articulation in speech synchronized viseme synthesis without sacrificing any performance. The objective and subjective experiments show that the system is suitable for human-machine interaction.

Controversies surrounding Human Papilloma Virus infection, head & neck vs oral cancer, implications for prophylaxis and treatment

OpenAIRE

Campisi, G.; Giovannelli, L.

2009-01-01

Head & Neck Cancer (HNC) represents the sixth most common malignancy worldwide and it is historically linked to well-known behavioural risk factors, i.e., tobacco smoking and/or the alcohol consumption. Recently, substantial evidence has been mounting that Human Papillomavirus (HPV) infection is playing an increasing important role in oral cancer. Because of the attention and clamor surrounding oral HPV infection and related cancers, as well as the use of HPV prophylactic vaccines, in this in...

The future of human rights impact assessments of trade agreements

NARCIS (Netherlands)

Walker, S.M.

2009-01-01

The Future of Human Rights Impact Assessments of Trade Agreements develops a methodology for human rights impact assessments of trade agreements and considers whether there is any value in using the methodology on a sustained basis to ensure that the human dimensions of international trade are taken

64Cu-DOTATATE PET for Neuroendocrine Tumors: a Prospective Head-to-Head Comparison with 111In-DTPA-octreotide in 112 Patients

DEFF Research Database (Denmark)

Pfeifer, Andreas Klaus; Knigge, Ulrich; Binderup, Tina

2015-01-01

Neuroendocrine tumors (NETs) can be visualized using radiolabeled somatostatin analogs. We have previously shown the clinical potential of (64)Cu-DOTATATE in a small first-in-human feasibility study. The aim of the present study was, in a larger prospective design, to compare on a head-to-head ba...

New developments in the management of head and neck cancer – impact of pembrolizumab

Directory of Open Access Journals (Sweden)

Saleh K

2018-02-01

Full Text Available Khalil Saleh, Roland Eid, Fady GH Haddad, Nadine Khalife-Saleh, Hampig Raphaël Kourie Oncology Department, Faculty of Medicine, Saint Joseph University, Beirut, Lebanon Abstract: Head and neck squamous cell carcinoma (HNSCC, a heterogeneous group of upper aerodigestive tract malignancies, is the seventh most common cancer worldwide. Tobacco use and alcohol consumption were the most identified risk factors of HNSCC. However, human papilloma virus, a sexually transmitted infection, has been determined as another primary cause of HNSCC. Early-stage disease is treated with surgery or radiotherapy. Recurrent or metastatic HNSCC is associated with poor prognosis with a median overall survival of 10 months. The EXTREME protocol is commonly used in first-line setting. Recently, pembrolizumab, an anti-programmed death-1 agent, has been approved by the US Food and Drug Administration for the treatment of patients with recurrent or metastatic squamous cell carcinoma of the head and neck with disease progression on or after a platinum-based therapy. It demonstrated a durable objective response rate with a good safety profile and quality of life. Many ongoing trials are evaluating the use of pembrolizumab for the treatment of HNSCC in various indications such as adjuvant and neoadjuvant setting, maintenance and recurrent disease, alone or in combination with chemotherapy, radiation and targeted therapy. Finding those biomarkers predictive of response to immune checkpoints inhibitors has been a major concern. However, markers have been identified, such as PD-L1 expression, human papilloma virus infection, interferon-γ signature score, microsatellite instability and neoantigen production. Keywords: epidemiology, HPV, pharmacokinetics, PD-1/PD-L1 inhibitors, immunotherapy, biomarkers

Does aquatic foraging impact head shape evolution in snakes?

Science.gov (United States)

Segall, Marion; Cornette, Raphaël; Fabre, Anne-Claire; Godoy-Diana, Ramiro; Herrel, Anthony

2016-08-31

Evolutionary trajectories are often biased by developmental and historical factors. However, environmental factors can also impose constraints on the evolutionary trajectories of organisms leading to convergence of morphology in similar ecological contexts. The physical properties of water impose strong constraints on aquatic feeding animals by generating pressure waves that can alert prey and potentially push them away from the mouth. These hydrodynamic constraints have resulted in the independent evolution of suction feeding in most groups of secondarily aquatic tetrapods. Despite the fact that snakes cannot use suction, they have invaded the aquatic milieu many times independently. Here, we test whether the aquatic environment has constrained head shape evolution in snakes and whether shape converges on that predicted by biomechanical models. To do so, we used three-dimensional geometric morphometrics and comparative, phylogenetically informed analyses on a large sample of aquatic snake species. Our results show that aquatic snakes partially conform to our predictions and have a narrower anterior part of the head and dorsally positioned eyes and nostrils. This morphology is observed, irrespective of the phylogenetic relationships among species, suggesting that the aquatic environment does indeed drive the evolution of head shape in snakes, thus biasing the evolutionary trajectory of this group of animals. © 2016 The Author(s).

Visualization of light propagation in visible Chinese human head for functional near-infrared spectroscopy

Science.gov (United States)

Li, Ting; Gong, Hui; Luo, Qingming

2011-04-01

Using the visible Chinese human data set, which faithfully represents human anatomy, we visualize the light propagation in the head in detail based on Monte Carlo simulation. The simulation is verified to agree with published experimental results in terms of a differential path-length factor. The spatial sensitivity profile turns out to seem like a fat tropical fish with strong distortion along the folding cerebral surface. The sensitive brain region covers the gray matter and extends to the superficial white matter, leading to a large penetration depth (>3 cm). Finally, the optimal source-detector separation is suggested to be narrowed down to 3-3.5 cm, while the sensitivity of the detected signal to brain activation reaches the peak of 8%. These results indicate that the cerebral cortex folding geometry actually has substantial effects on light propagation, which should be necessarily considered for applications of functional near-infrared spectroscopy.

Mummified trophy heads from Peru: diagnostic features and medicolegal significance.

Science.gov (United States)

Verano, John W

2003-05-01

Several forms of mummified human trophy heads were produced by prehistoric and historic native groups in South America. This paper describes the diagnostic features of trophy heads produced by the Nasca culture of ancient Peru. A growing interest in these mummified heads among collectors of Pre-Columbian art and antiquities has led to their illegal exportation from Peru, in violation of national and international antiquities laws. Requests from the Peruvian government to protect its cultural patrimony led the United States in 1997 to declare these heads as items subject to U.S. import restriction, along with six other categories of human remains. Despite such restrictions, Nasca trophy heads continue to reach private collectors outside of Peru and thus may be encountered by local, state, or federal law enforcement officials unfamiliar with their characteristic features and origin. The objective of this paper is to describe the features that allow Nasca trophy heads to be identified and distinguished from other archaeological and forensic specimens that may be submitted to a forensic anthropologist for identification.

Axis of eye rotation changes with head-pitch orientation during head impulses about earth-vertical.

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Migliaccio, Americo A; Schubert, Michael C; Clendaniel, Richard A; Carey, John P; Della Santina, Charles C; Minor, Lloyd B; Zee, David S

2006-06-01

The goal of this study was to assess how the axis of head rotation, Listing's law, and eye position influence the axis of eye rotation during brief, rapid head rotations. We specifically asked how the axis of eye rotation during the initial angular vestibuloocular reflex (VOR) changed when the pitch orientation of the head relative to Earth-vertical was varied, but the initial position of the eye in the orbit and the orientation of Listing's plane with respect to the head were fixed. We measured three-dimensional eye and head rotation axes in eight normal humans using the search coil technique during head-and-trunk (whole-body) and head-on-trunk (head-only) "impulses" about an Earth-vertical axis. The head was initially oriented at one of five pitch angles (30 degrees nose down, 15 degrees nose down, 0 degrees, 15 degrees nose up, 30 degrees nose up). The fixation target was always aligned with the nasooccipital axis. Whole-body impulses were passive, unpredictable, manual, rotations with peak-amplitude of approximately 20 degrees , peak-velocity of approximately 80 degrees /s, and peak-acceleration of approximately 1000 degrees /s2. Head-only impulses were also passive, unpredictable, manual, rotations with peak-amplitude of approximately 20 degrees , peak-velocity of approximately 150 degrees /s, and peak-acceleration of approximately 3000 degrees /s2. During whole-body impulses, the axis of eye rotation tilted in the same direction, and by an amount proportional (0.51 +/- 0.09), to the starting pitch head orientation (P rotation could be predicted from vectorial summation of the gains (eye velocity/head velocity) obtained for rotations about the pure yaw and roll head axes. Thus, even when the orientation of Listing's plane and eye position in the orbit are fixed, the axis of eye rotation during the VOR reflects a compromise between the requirements of Listing's law and a perfectly compensatory VOR.

Knowledge of human papillomavirus and its association with head and neck benign and malignant lesions in a group of dental patients in pakistan.

Science.gov (United States)

Gichki, Abdul Samad; Buajeeb, Waranun; Doungudomdacha, Sombhun; Khovidhunkit, Siribang-On Pibooniyom

2015-01-01

Human papillomaviruses (HPVs) remain a serious world health problem due to their association with cervical and head and neck cancers. While over 100 HPV types have been identified, only a few subtypes are associated with malignancies. HPV 16 and 18 are the most prevalent oncogenic types in head and neck cancers. Although it has been proven that some subsets of benign and malignant head and neck lesions are associated with HPV, the general population have very little awareness and knowledge of their association with HPV. Therefore, the purpose of this study was to determine the knowledge of HPV and its links with head and neck benign and malignant lesions in a group of Pakistani dental patients who attended the Dental Department of the Sandeman provincial hospital in Quetta, Pakistan. One hundred and ninety-two patients were recruited and requested to answer a questionnaire. It was revealed that there was a low level of knowledge about HPV and its association with head and neck benign and malignant lesions among the participants. This result suggested that more education regarding the relationship of HPV in inducing head and neck benign and malignant lesions is required in this group of patients.

Biomechanics of Heading a Soccer Ball: Implications for Player Safety

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Charles F. Babbs

2001-01-01

Full Text Available To better understand the risk and safety of heading a soccer ball, the author created a set of simple mathematical models based upon Newton�s second law of motion to describe the physics of heading. These models describe the player, the ball, the flight of the ball before impact, the motion of the head and ball during impact, and the effects of all of these upon the intensity and the duration of acceleration of the head. The calculated head accelerations were compared to those during presumably safe daily activities of jumping, dancing, and head nodding and also were related to established criteria for serious head injury from the motor vehicle crash literature. The results suggest heading is usually safe but occasionally dangerous, depending on key characteristics of both the player and the ball. Safety is greatly improved when players head the ball with greater effective body mass, which is determined by a player�s size, strength, and technique. Smaller youth players, because of their lesser body mass, are more at risk of potentially dangerous headers than are adults, even when using current youth size balls. Lower ball inflation pressure reduces risk of dangerous head accelerations. Lower pressure balls also have greater “touch” and “playability”, measured in terms of contact time and contact area between foot and ball during a kick. Focus on teaching proper technique, the re-design of age-appropriate balls for young players with reduced weight and inflation pressure, and avoidance of head contact with fast, rising balls kicked at close range can substantially reduce risk of subtle brain injury in players who head soccer balls.

Smad4 loss in mice causes spontaneous head and neck cancer with increased genomic instability and inflammation.

Science.gov (United States)

Bornstein, Sophia; White, Ruth; Malkoski, Stephen; Oka, Masako; Han, Gangwen; Cleaver, Timothy; Reh, Douglas; Andersen, Peter; Gross, Neil; Olson, Susan; Deng, Chuxia; Lu, Shi-Long; Wang, Xiao-Jing

2009-11-01

Smad4 is a central mediator of TGF-beta signaling, and its expression is downregulated or lost at the malignant stage in several cancer types. In this study, we found that Smad4 was frequently downregulated not only in human head and neck squamous cell carcinoma (HNSCC) malignant lesions, but also in grossly normal adjacent buccal mucosa. To gain insight into the importance of this observation, we generated mice in which Smad4 was deleted in head and neck epithelia (referred to herein as HN-Smad4-/- mice) and found that they developed spontaneous HNSCC. Interestingly, both normal head and neck tissue and HNSCC from HN-Smad4-/- mice exhibited increased genomic instability, which correlated with downregulated expression and function of genes encoding proteins in the Fanconi anemia/Brca (Fanc/Brca) DNA repair pathway linked to HNSCC susceptibility in humans. Consistent with this, further analysis revealed a correlation between downregulation of Smad4 protein and downregulation of the Brca1 and Rad51 proteins in human HNSCC. In addition to the above changes in tumor epithelia, both normal head and neck tissue and HNSCC from HN-Smad4-/- mice exhibited severe inflammation, which was associated with increased expression of TGF-beta1 and activated Smad3. We present what we believe to be the first single gene-knockout model for HNSCC, in which both HNSCC formation and invasion occurred as a result of Smad4 deletion. Our results reveal an intriguing connection between Smad4 and the Fanc/Brca pathway and highlight the impact of epithelial Smad4 loss on inflammation.

Primary Radiation Therapy for Head-and-Neck Cancer in the Setting of Human Immunodeficiency Virus

International Nuclear Information System (INIS)

Klein, Emily A.; Guiou, Michael; Farwell, D. Gregory; Luu, Quang; Lau, Derick H.; Stuart, Kerri; Vaughan, Andrew; Vijayakumar, Srinivasan; Chen, Allen M.

2011-01-01

Purpose: To analyze outcomes after radiation therapy for head-and-neck cancer among a cohort of patients with human immunodeficiency virus (HIV). Methods and Materials: The medical records of 12 patients with serologic evidence of HIV who subsequently underwent radiation therapy to a median dose of 68 Gy (range, 64-72 Gy) for newly diagnosed squamous cell carcinoma of the head and neck were reviewed. Six patients (50%) received concurrent chemotherapy. Intensity-modulated radiotherapy was used in 6 cases (50%). All patients had a Karnofsky performance status of 80 or 90. Nine patients (75%) were receiving antiretroviral therapies at the time of treatment, and the median CD4 count was 460 (range, 266-800). Toxicity was graded according to the Radiation Therapy Oncology Group / European Organization for the Treatment of Cancer toxicity criteria. Results: The 3-year estimates of overall survival and local-regional control were 78% and 92%, respectively. Acute Grade 3+ toxicity occurred in 7 patients (58%), the most common being confluent mucositis (5 patients) and moist skin desquamation (4 patients). Two patients experienced greater than 10% weight loss, and none experienced more than 15% weight loss from baseline. Five patients (42%) experienced treatment breaks in excess of 10 cumulative days, although none required hospitalization. There were no treatment-related fatalities. Conclusions: Radiation therapy for head-and-neck cancer seems to be relatively well tolerated among appropriately selected patients with HIV. The observed rates of toxicity were comparable to historical controls without HIV.

Pocket Proteins Suppress Head and Neck Cancer

Science.gov (United States)

Shin, Myeong-Kyun; Pitot, Henry C.; Lambert, Paul F.

2012-01-01

Head and neck squamous cell carcinomas (HNSCC) is a common cancer in humans long known to be caused by tobacco and alcohol use, but now an increasing percentage of HNSCC is recognized to be caused by the same human papillomaviruses (HPVs) that cause cervical and other anogenital cancers. HPV-positive HNSCCs differ remarkably from HPV-negative HNSCCs in their clinical response and molecular properties. From studies in mice, we know that E7 is the dominant HPV oncoprotein in head and neck cancer. E7 is best known for its ability to inactivate pRb, the product of the retinoblastoma tumor susceptibility gene. However loss of pRb function does not fully account for E7’s potency in causing head and neck cancer. In this study, we characterized the cancer susceptibility of mice deficient in the expression of pRb and either of two related “pocket” proteins, p107 and p130, that are also inactivated by E7. pRb/p107 deficient mice developed head and neck cancer as frequently as do HPV16 E7 transgenic mice. The head and neck epithelia of the pRb/p107 deficient mice also displayed the same acute phenotypes and biomarker readouts as observed in the epithelia of E7 transgenic mice. Mice deficient for pRb and p130 in their head and neck epithelia showed intermediate acute and tumor phenotypes. We conclude that pRb and p107 act together to efficiently suppress head and neck cancer, and are therefore highly relevant targets of HPV16 E7 in its contribution to HPV-positive HNSCC. PMID:22237625

Head-Mounted Display Technology for Low Vision Rehabilitation and Vision Enhancement

Science.gov (United States)

Ehrlich, Joshua R.; Ojeda, Lauro V.; Wicker, Donna; Day, Sherry; Howson, Ashley; Lakshminarayanan, Vasudevan; Moroi, Sayoko E.

2017-01-01

Purpose To describe the various types of head-mounted display technology, their optical and human factors considerations, and their potential for use in low vision rehabilitation and vision enhancement. Design Expert perspective. Methods An overview of head-mounted display technology by an interdisciplinary team of experts drawing on key literature in the field. Results Head-mounted display technologies can be classified based on their display type and optical design. See-through displays such as retinal projection devices have the greatest potential for use as low vision aids. Devices vary by their relationship to the user’s eyes, field of view, illumination, resolution, color, stereopsis, effect on head motion and user interface. These optical and human factors considerations are important when selecting head-mounted displays for specific applications and patient groups. Conclusions Head-mounted display technologies may offer advantages over conventional low vision aids. Future research should compare head-mounted displays to commonly prescribed low vision aids in order to compare their effectiveness in addressing the impairments and rehabilitation goals of diverse patient populations. PMID:28048975

COMPARISON OF A HEAD MOUNTED IMPACT MEASUREMENT DEVICE TO THE HYBRID III ANTHROPOMORPHIC TESTING DEVICE IN A CONTROLLED LABORATORY SETTING.

Science.gov (United States)

Schussler, Eric; Stark, David; Bolte, John H; Kang, Yun Seok; Onate, James A

2017-08-01

Reports estimate that 1.6 to 3.8 million cases of concussion occur in sports and recreation each year in the United States. Despite continued efforts to reduce the occurrence of concussion, the rate of diagnosis continues to increase. The mechanisms of concussion are thought to involve linear and rotational head accelerations and velocities. One method of quantifying the kinematics experienced during sport participation is to place measurement devices into the athlete's helmet or directly on the athlete's head. The purpose of this research to determine the accuracy of a head mounted device for measuring the head accelerations experienced by the wearer. This will be accomplished by identifying the error in Peak Linear Acceleration (PLA), Peak Rotational Acceleration (PRA) and Peak Rotational Velocity (PRV) of the device. Laboratory study. A helmeted Hybrid III 50th percentile male headform was impacted via a pneumatic ram from the front, side, rear, front oblique and rear oblique at speeds from 1.5 to 5 m/s. The X2 Biosystems xPatch® (Seattle, WA) sensor was placed on the headform's right side at the approximate location of the mastoid process. Measures of PLA, PRA, PRV from the xPatch ® and Hybrid III were analyzed for Root Mean Square Error (RMSE), and Absolute and Relative Error (AE, RE). Seventy-six impacts were analyzed. All measures of correlation, fixed through the origin, were found to be strong: PLA R 2 =0.967 pstandard yet above the average error of testing devices in both PLA and PRA, but a low error in PRV. PLA measures from the xPatch® system demonstrated a high level of correlation with the PLA data from the Hybrid III mounted data collection system. 3.

Survey of Permethrin and Malathion Resistance in Human Head Lice Populations from Denmark

DEFF Research Database (Denmark)

Kristensen, Michael; Knorr, Mette; Rasmussen, Anne-Marie

2006-01-01

was selected, 2 ng of permethrin and 100 ng of malathion per head louse, respectively. Head lice were collected from heads of infested children in Denmark at 33 primary schools, one kindergarten, and seven boarding schools. The lice were collected by combing of dry hair, with a fine-toothed antilouse comb...

Nintendo Wii remote controllers for head posture measurement: accuracy, validity, and reliability of the infrared optical head tracker.

Science.gov (United States)

Kim, Jongshin; Nam, Kyoung Won; Jang, Ik Gyu; Yang, Hee Kyung; Kim, Kwang Gi; Hwang, Jeong-Min

2012-03-15

To evaluate the accuracy, validity, and reliability of a newly developed infrared optical head tracker (IOHT) using Nintendo Wii remote controllers (WiiMote; Nintendo Co. Ltd., Kyoto, Japan) for measurement of the angle of head posture. The IOHT consists of two infrared (IR) receivers (WiiMote) that are fixed to a mechanical frame and connected to a monitoring computer via a Bluetooth communication channel and an IR beacon that consists of four IR light-emitting diodes (LEDs). With the use of the Cervical Range of Motion (CROM; Performance Attainment Associates, St. Paul, MN) as a reference, one- and three-dimensional (1- and 3-D) head postures of 20 normal adult subjects (20-37 years of age; 9 women and 11 men) were recorded with the IOHT. In comparison with the data from the CROM, the IOHT-derived results showed high consistency. The measurements of 1- and 3-D positions of the human head with the IOHT were very close to those of the CROM. The correlation coefficients of 1- and 3-D positions between the IOHT and the CROM were more than 0.99 and 0.96 (P < 0.05, Pearson's correlation test), respectively. Reliability tests of the IOHT for the normal adult subjects for 1- and 3-D positions of the human head had 95% limits of agreement angles of approximately ±4.5° and ±8.0°, respectively. The IOHT showed strong concordance with the CROM and relatively good test-retest reliability, thus proving its validity and reliability as a head-posture-measuring device. Considering its high performance, ease of use, and low cost, the IOHT has the potential to be widely used as a head-posture-measuring device in clinical practice.

Head, Neck, and Oral Cancer

Medline Plus

Full Text Available ... Oral, Head and Neck Pathology TMJ and Facial Pain Wisdom Teeth Management Procedures Anesthesia Anesthesia Oral and maxillofacial surgeons are ... more. TMJ and Facial Pain TMJ and Facial ... Teeth Management Wisdom Teeth Management An impacted wisdom tooth can ...

Precise Head Tracking in Hearing Applications

Science.gov (United States)

Helle, A. M.; Pilinski, J.; Luhmann, T.

2015-05-01

The paper gives an overview about two research projects, both dealing with optical head tracking in hearing applications. As part of the project "Development of a real-time low-cost tracking system for medical and audiological problems (ELCoT)" a cost-effective single camera 3D tracking system has been developed which enables the detection of arm and head movements of human patients. Amongst others, the measuring system is designed for a new hearing test (based on the "Mainzer Kindertisch"), which analyzes the directional hearing capabilities of children in cooperation with the research project ERKI (Evaluation of acoustic sound source localization for children). As part of the research project framework "Hearing in everyday life (HALLO)" a stereo tracking system is being used for analyzing the head movement of human patients during complex acoustic events. Together with the consideration of biosignals like skin conductance the speech comprehension and listening effort of persons with reduced hearing ability, especially in situations with background noise, is evaluated. For both projects the system design, accuracy aspects and results of practical tests are discussed.

The Relationship Between Human Papillomavirus Status and Other Molecular Prognostic Markers in Head and Neck Squamous Cell Carcinomas

International Nuclear Information System (INIS)

Kong, Christina S.; Narasimhan, Balasubramanian; Cao Hongbin; Kwok, Shirley; Erickson, Julianna P.; Koong, Albert; Pourmand, Nader; Le, Quynh-Thu

2009-01-01

Purpose: To evaluate the relationship between human papillomavirus (HPV) status and known prognostic makers for head and neck cancers including tumor hypoxia, epidermal growth factor receptor (EGFR) expression and intratumoral T-cell levels and to determine the prognostic impact of these markers by HPV status. Methods and Materials: HPV status in 82 evaluable head and neck squamous cell carcinomas patients was determined by pyrosequencing and related to p16 INK4a staining and treatment outcomes. It was correlated with tumor hypoxia (tumor pO 2 and carbonic anhydrase [CAIX] staining), EGFR status, and intratumoral lymphocyte expression (CD3 staining). Results: Forty-four percent of evaluable tumors had strong HPV signal by pyrosequencing. There was a significant relationship between strong HPV signal and p16 INK4a staining as well as oropharynx location. The strong HPV signal group fared significantly better than others, both in time to progression (TTP, p = 0.008) and overall survival (OS, p = 0.004) for all patients and for the oropharyngeal subset. Positive p16 INK4a staining was associated with better TTP (p = 0.014) and OS (p = 0.00002). There was no relationship between HPV status and tumor pO 2 or CAIX staining. However, HPV status correlated inversely with EGFR reactivity (p = 0.0006) and directly with CD3(+) T-lymphocyte level (p = 0.03). Whereas CAIX and EGFR overexpression were negative prognostic factors regardless of HPV status, CD3(+) T-cell levels was prognostic only in HPV(-) tumors. Conclusion: HPV status was a prognostic factor for progression and survival. It correlated inversely with EGFR expression and directly with T-cell infiltration. The prognostic effect of CAIX and EGFR expression was not influenced by HPV status, whereas intratumoral T-cell levels was significant only for HPV(-) tumors.

Regional differences in islet distribution in the human pancreas--preferential beta-cell loss in the head region in patients with type 2 diabetes.

Directory of Open Access Journals (Sweden)

Xiaojun Wang

Full Text Available While regional heterogeneity in islet distribution has been well studied in rodents, less is known about human pancreatic histology. To fill gaps in our understanding, regional differences in the adult human pancreas were quantitatively analyzed including the pathogenesis of type 2 diabetes (T2D. Cadaveric pancreas specimens were collected from the head, body and tail regions of each donor, including subjects with no history of diabetes or pancreatic diseases (n = 23 as well as patients with T2D (n = 12. The study further included individuals from whom islets were isolated (n = 7 to study islet yield and function in a clinical setting of islet transplantation. The whole pancreatic sections were examined using an innovative large-scale image capture and unbiased detailed quantitative analyses of the characteristics of islets from each individual (architecture, size, shape and distribution. Islet distribution/density is similar between the head and body regions, but is >2-fold higher in the tail region. In contrast to rodents, islet cellular composition and architecture were similar throughout the pancreas and there was no difference in glucose-stimulated insulin secretion in islets isolated from different regions of the pancreas. Further studies revealed preferential loss of large islets in the head region in patients with T2D. The present study has demonstrated distinct characteristics of the human pancreas, which should provide a baseline for the future studies integrating existing research in the field and helping to advance bi-directional research between humans and preclinical models.

The state of head injury biomechanics: past, present, and future part 2: physical experimentation.

Science.gov (United States)

Goldsmith, Werner; Monson, Kenneth L

2005-01-01

This presentation is the continuation of the article published in Critical Reviews of Biomedical Engineering, 29(5-6), 2001. That issue contained topics dealing with components and geometry of the human head, classification of head injuries, some early experimental studies, and tolerance considerations. It then dealt with head motion and load characterization, investigations during the period from 1939 to 1966, injury causation and early modeling efforts, the 1966 Head Injury Conference and its sequels, mechanical properties of solid tissues, fluid characterization, and early investigation of the mechanical properties of cranial materials. It continued with a description of the systematic investigations of solid cranial components and structural properties since 1966, fetal cranial properties, analytical head modeling, and numerical solutions of head injury. The paper concluded with experimental dynamic loading of human living and cadaver heads, dynamic loading of surrogate heads, and head injury mechanics. This portion of the paper describes physical head injury experimentation involving animals, primarily primates, human cadavers, volunteers, and inanimate physical models. In order to address the entire domain of head injury biomechanics in the two-part survey, it was intended that this information be supplemented by discussions of head injury tolerance and criteria, automotive and sports safety considerations, and the design of protective equipment, but Professor Goldsmith passed away before these sections could be completed. It is nevertheless anticipated that this attenuated installment will provide, in conjunction with the first part of the survey, a valuable resource for students and practitioners of head injury biomechanics.

The estimation of 3D SAR distributions in the human head from mobile phone compliance testing data for epidemiological studies

International Nuclear Information System (INIS)

Wake, Kanako; Watanabe, Soichi; Taki, Masao; Varsier, Nadege; Wiart, Joe; Mann, Simon; Deltour, Isabelle; Cardis, Elisabeth

2009-01-01

A worldwide epidemiological study called 'INTERPHONE' has been conducted to estimate the hypothetical relationship between brain tumors and mobile phone use. In this study, we proposed a method to estimate 3D distribution of the specific absorption rate (SAR) in the human head due to mobile phone use to provide the exposure gradient for epidemiological studies. 3D SAR distributions due to exposure to an electromagnetic field from mobile phones are estimated from mobile phone compliance testing data for actual devices. The data for compliance testing are measured only on the surface in the region near the device and in a small 3D region around the maximum on the surface in a homogeneous phantom with a specific shape. The method includes an interpolation/extrapolation and a head shape conversion. With the interpolation/extrapolation, SAR distributions in the whole head are estimated from the limited measured data. 3D SAR distributions in the numerical head models, where the tumor location is identified in the epidemiological studies, are obtained from measured SAR data with the head shape conversion by projection. Validation of the proposed method was performed experimentally and numerically. It was confirmed that the proposed method provided good estimation of 3D SAR distribution in the head, especially in the brain, which is the tissue of major interest in epidemiological studies. We conclude that it is possible to estimate 3D SAR distributions in a realistic head model from the data obtained by compliance testing measurements to provide a measure for the exposure gradient in specific locations of the brain for the purpose of exposure assessment in epidemiological studies. The proposed method has been used in several studies in the INTERPHONE.

Human Cloning

Science.gov (United States)

2006-07-20

Human Fertilization and Embryology Authority (HFEA). A team of scientists headed by Alison Murdoch at the University of Newcastle received permission...not yet reported success in isolating stem cells from a cloned human embryo. A research team headed by Ian Wilmut at the University of Edinburgh...research group, headed by Douglas Melton and Kevin Eggan, submitted their proposal to a Harvard committee composed of ethicists, scientists and public

The current status of oncolytic viral therapy for head and neck cancer

Directory of Open Access Journals (Sweden)

Matthew O. Old

2016-06-01

Full Text Available Objective: Cancer affects the head and neck region frequently and leads to significant morbidity and mortality. Oncolytic viral therapy has the potential to make a big impact in cancers that affect the head and neck. We intend to review the current state of oncolytic viruses in the treatment of cancers that affect the head and neck region. Method: Data sources are from National clinical trials database, literature, and current research. Results: There are many past and active trials for oncolytic viruses that show promise for treating cancers of the head and neck. The first oncolytic virus was approved by the FDA October 2015 (T-VEC, Amgen for the treatment of melanoma. Active translational research continues for this and many other oncolytic viruses. Conclusion: The evolving field of oncolytic viruses is impacting the treatment of head and neck cancer and further trials and agents are moving forward in the coming years. Keywords: Head and neck squamous cell carcinoma, Oncolytic viruses, Clinical trials, Novel therapeutics

Human surrogate neck response to +Gz vertical impact

NARCIS (Netherlands)

Rooij, L. van; Uittenbogaard, J.

2011-01-01

For the evaluation of impact scenarios with a substantial vertical component, the performance of current human surrogates - the RID 3D hardware dummy and two numerical human models - was evaluated. Volunteer tests with 10G and 6G pulses were compared to reconstructed tests with human surrogates.

Hydrological impacts of global land cover change and human water use

NARCIS (Netherlands)

Bosmans, J.H.C.; van Beek, L.P.H.; Sutanudjaja, E.H.; Bierkens, M.F.P.

2017-01-01

Human impacts on global terrestrial hydrology have been accelerating during the 20th century. These human impacts include the effects of reservoir building and human water use, as well as land cover change. To date, many global studies have focussed on human water use, but only a few focus on or

Impact of comorbidity on treatment outcome in head and neck squamous cell carcinoma – A systematic review

International Nuclear Information System (INIS)

Bøje, Charlotte Rotbøl

2014-01-01

The significant association with tobacco and alcohol combined with advanced age at time of diagnosis predispose head and neck squamous cell carcinoma (HNSCC) patients to increased risk of comorbidities. The presence of comorbidity affects treatment, treatment selection and subsequent outcome. Multiple studies have demonstrated comorbidity to be a strong prognostic factor for survival, and therefore comorbidity can be a major confounder in clinical trials. This review provides a summary of the current literature on comorbidity in head and neck cancer, measurements of comorbidity, the impact of comorbidity on treatment, treatment selection, and survival. A systematic search was performed in six electronic databases. In all, 31 papers were selected for this review. A meta-analysis on the prognostic impact of comorbidity was performed including 10 studies. Furthermore, 21 studies concerning comorbidity were reviewed. Several valid indices to classify comorbidity were described in the literature, none proven to be superior over the other. The prevalence of comorbidity increased with age and the presence of comorbidity influenced treatment and treatment selection. Furthermore, comorbidity was associated with lower socio economic status and increased the risk of early retirement after treatment. The meta-analysis on comorbidity as a prognostic factor, including 22,932 patients, showed that overall survival was significantly worsened among patients with comorbidity (HR = 1.38 (1.32–1.43)). Increasing comorbidity-score was associated with increased risk of death. Comorbidity is important in HNSCC and significantly impacts on overall survival. Trials concerning HNSCC should always include information on comorbidity and randomized trials should stratify patients according to comorbidity in order to avoid bias in the study

Assessing corporate project impacts in changeable contexts: A human rights perspective

Energy Technology Data Exchange (ETDEWEB)

Salcito, Kendyl, E-mail: kendyl.salcito@unibas.ch [Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, P.O. Box, CH-4002 Basel (Switzerland); University of Basel, P.O. Box, CH-4003 Basel (Switzerland); NomoGaia, 1900 Wazee Street, Suite 303, Denver, CO 80202 (United States); NewFields, LLC, Denver, CO 80202 (United States); Singer, Burton H., E-mail: bhsinger@epi.ufl.edu [Emerging Pathogens Institute, University of Florida, Gainesville, FL 32610 (United States); Krieger, Gary R., E-mail: gkrieger@newfields.com [NewFields, LLC, Denver, CO 80202 (United States); Weiss, Mitchell G., E-mail: mitchell-g.weiss@unibas.ch [Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, P.O. Box, CH-4002 Basel (Switzerland); University of Basel, P.O. Box, CH-4003 Basel (Switzerland); Wielga, Mark, E-mail: wielga@nomogaia.org [NomoGaia, 1900 Wazee Street, Suite 303, Denver, CO 80202 (United States); NewFields, LLC, Denver, CO 80202 (United States); Utzinger, Jürg, E-mail: juerg.utzinger@unibas.ch [Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, P.O. Box, CH-4002 Basel (Switzerland); University of Basel, P.O. Box, CH-4003 Basel (Switzerland)

2014-07-01

Project-level impact assessment was originally conceived as a snapshot taken in advance of project implementation, contrasting current conditions with a likely future scenario involving a variety of predicted impacts. Current best practice guidance has encouraged a shift towards longitudinal assessments from the pre-project stage through the implementation and operating phases. Experience and study show, however, that assessment of infrastructure-intensive projects rarely endures past the project's construction phase. Negative consequences for environmental, social and health outcomes have been documented. Such consequences clarify the pressing need for longitudinal assessment in each of these domains, with human rights impact assessment (HRIA) as an umbrella over, and critical augmentation of, environmental, social and health assessments. Project impacts on human rights are more closely linked to political, economic and other factors beyond immediate effects of a company's policy and action throughout the project lifecycle. Delineating these processes requires an adequate framework, with strategies for collecting longitudinal data, protocols that provide core information for impact assessment and guidance for adaptive mitigation strategies as project-related effects change over time. This article presents general principles for the design and implementation of sustained, longitudinal HRIA, based on experience assessing and responding to human rights impact in a uranium mining project in Malawi. The case study demonstrates the value of longitudinal assessment both for limiting corporate risk and improving human welfare. - Graphical abstract: Assessing changes in human rights condition as affected by both project and context, over time. - Highlights: • Corporate capital projects affect human rights in myriad ways. • Ongoing, longitudinal impact assessment techniques are needed. • We present an approach for conducting longitudinal human rights impact

Assessing corporate project impacts in changeable contexts: A human rights perspective

International Nuclear Information System (INIS)

Salcito, Kendyl; Singer, Burton H.; Krieger, Gary R.; Weiss, Mitchell G.; Wielga, Mark; Utzinger, Jürg

2014-01-01

Project-level impact assessment was originally conceived as a snapshot taken in advance of project implementation, contrasting current conditions with a likely future scenario involving a variety of predicted impacts. Current best practice guidance has encouraged a shift towards longitudinal assessments from the pre-project stage through the implementation and operating phases. Experience and study show, however, that assessment of infrastructure-intensive projects rarely endures past the project's construction phase. Negative consequences for environmental, social and health outcomes have been documented. Such consequences clarify the pressing need for longitudinal assessment in each of these domains, with human rights impact assessment (HRIA) as an umbrella over, and critical augmentation of, environmental, social and health assessments. Project impacts on human rights are more closely linked to political, economic and other factors beyond immediate effects of a company's policy and action throughout the project lifecycle. Delineating these processes requires an adequate framework, with strategies for collecting longitudinal data, protocols that provide core information for impact assessment and guidance for adaptive mitigation strategies as project-related effects change over time. This article presents general principles for the design and implementation of sustained, longitudinal HRIA, based on experience assessing and responding to human rights impact in a uranium mining project in Malawi. The case study demonstrates the value of longitudinal assessment both for limiting corporate risk and improving human welfare. - Graphical abstract: Assessing changes in human rights condition as affected by both project and context, over time. - Highlights: • Corporate capital projects affect human rights in myriad ways. • Ongoing, longitudinal impact assessment techniques are needed. • We present an approach for conducting longitudinal human rights impact assessment

Gene Expression Changes in Femoral Head Necrosis of Human Bone Tissue

Directory of Open Access Journals (Sweden)

Bernadett Balla

2011-01-01

Full Text Available Osteonecrosis of the femoral head (ONFH is the result of an interruption of the local circulation and the injury of vascular supply of bone. Multiple factors have been implicated in the development of the disease. However the mechanism of ischemia and necrosis in non-traumatic ONFH is not clear. The aim of our investigation was to identify genes that are differently expressed in ONFH vs. non-ONFH human bone and to describe the relationships between these genes using multivariate data analysis. Six bone tissue samples from ONFH male patients and 8 bone tissue samples from non-ONFH men were examined. The expression differences of selected 117 genes were analyzed by TaqMan probe-based quantitative real-time RT-PCR system. The significance test indicated marked differences in the expression of nine genes between ONFH and non-ONFH individuals. These altered genes code for collagen molecules, an extracellular matrix digesting metalloproteinase, a transcription factor, an adhesion molecule, and a growth factor. Canonical variates analysis demonstrated that ONFH and non-ONFH bone tissues can be distinguished by the multiple expression profile analysis of numerous genes controlled via canonical TGFB pathway as well as genes coding for extracellular matrix composing collagen type molecules. The markedly altered gene expression profile observed in the ONFH of human bone tissue may provide further insight into the pathogenetic process of osteonecrotic degeneration of bone.

Factors affecting the aluminium content of human femoral head and neck.

Science.gov (United States)

Zioła-Frankowska, Anetta; Dąbrowski, Mikołaj; Kubaszewski, Łukasz; Rogala, Piotr; Frankowski, Marcin

2015-11-01

Tissues for the study were obtained intraoperatively during hip replacement procedures from 96 patients. In all the cases, the indication for this treatment was primary or secondary degenerative changes in the hip joint. The subject of the study was the head and neck of the femur, resected in situ. Aluminium concentrations measured in femoral head and neck samples from patients aged between 25 and 91 were varied. Statistical methods were applied to determine the variations in relation to the parameters from the background survey. Significant differences in the aluminium content of femoral head samples were observed between patients under and over 60 years of age. Based on the results, it was confirmed that the aluminium accumulates in bones over a lifetime. The study showed that the content of aluminium in the head and neck of the femur depends on the factors such as: type of medicines taken, contact with chemicals at work, differences in body anatomy and sex. The study on the levels of aluminium in bones and the factors affecting its concentration is a valuable source of information for further research on the role of aluminium in bone diseases. Based on the investigations, it was found that the GF-AAS technique is the best analytical tool for routine analysis of aluminium in complex matrix samples. The use of femoral heads in the investigations was approved by the Bioethics Committee of the University of Medical Sciences in Poznań (Poland). Copyright © 2015 Elsevier Inc. All rights reserved.

Designing safer composite helmets to reduce rotational accelerations during oblique impacts.

Science.gov (United States)

Mosleh, Yasmine; Cajka, Martin; Depreitere, Bart; Vander Sloten, Jos; Ivens, Jan

2018-05-01

Oblique impact is the most common accident situation that occupants in traffic accidents or athletes in professional sports experience. During oblique impact, the human head is subjected to a combination of linear and rotational accelerations. Rotational movement is known to be responsible for traumatic brain injuries. In this article, composite foam with a column/matrix composite configuration is proposed for head protection applications to replace single-layer uniform foam, to better attenuate rotational movement of the head during oblique impacts. The ability of composite foam in the mitigation of rotational head movement is studied by performing finite element (FE) simulations of oblique impact on flat and helmet shape specimens. The performance of composite foam with respect to parameters such as compliance of the matrix foam and the number, size and cross-sectional shape of the foam columns is explored in detail, and subsequently an optimized structure is proposed. The simulation results show that using composite foam instead of single-layer foam, the rotational acceleration and velocity of the headform can be significantly reduced. The parametric study indicates that using a more compliant matrix foam and by increasing the number of columns in the composite foam configuration, the rotation can be further mitigated. This was confirmed by experimental results. The simulation results were also analyzed based on global head injury criteria such as head injury criterion, rotational injury criterion, brain injury criterion and generalized acceleration model for brain injury threshold which further confirmed the superior performance of composite foam versus single-layer homogeneous expanded polystyrene foam. The findings of simulations give invaluable information for design of protective helmets or, for instance, headliners for the automotive industry.

Research progress of non-human species radiological impact and assessment

International Nuclear Information System (INIS)

Bai Xiaoping; Zhu Hao; Mao Yawei; Zheng Wei; Du Hongyan

2014-01-01

In recent years, with the development of radiological protection conception and the improvement of requirement about non-human species protection, much more attention has been paid gradually to biota radiation impact. Research and development of non-human species protection impact and its assessment at home and abroad are introduced, then RESRAD-BIOTA and ERICA which are comparatively mature codes in the world are compared and analyzed, at last some suggestions about research and assessment work of non-human species radiological impact in the future in China are provided. (authors)

Modelling and assessment of the electric field strength caused by mobile phone to the human head

Directory of Open Access Journals (Sweden)

Buckus Raimondas

2016-01-01

Full Text Available Background/Aim. Electromagnetic field exposure is the one of the most important physical agents that actively affects live organisms and environment. Active use of mobile phones influences the increase of electromagnetic field radiation. The aim of the study was to measure and assess the electric field strength caused by mobile phones to the human head. Methods. In this paper the software “COMSOL Multiphysics” was used to establish the electric field strength created by mobile phones around the head. Results. The second generation (2G Global System for Mobile (GSM phones that operate in the frequency band of 900 MHz and reach the power of 2 W have a stronger electric field than (2G GSM mobile phones that operate in the higher frequency band of 1,800 MHz and reach the power up to 1 W during conversation. The third generation of (3G UMTS smart phones that effectively use high (2,100 MHz radio frequency band emit the smallest electric field strength values during conversation. The highest electric field strength created by mobile phones is around the ear, i.e. the mobile phone location. The strength of mobile phone electric field on the phantom head decreases exponentially while moving sidewards from the center of the effect zone (the ear, and constitutes 1-12% of the artificial head’s surface. Conclusion. The highest electric field strength values of mobile phones are associated with their higher power, bigger specific energy absorption rate (SAR and lower frequency of mobile phone. The stronger electric field emitted by the more powerful mobile phones takes a higher percentage of the head surface. The highest electric field strength created by mobile phones is distributed over the user ear.

Low head hydro market assessment : main report : vol. 1

International Nuclear Information System (INIS)

2008-03-01

Hydroelectric power is a predictable renewable energy source that produces no greenhouse gases (GHGs) and has low maintenance costs. In addition to river resources, low head hydro is available in sluice gates, irrigation canals, drinking water pressure release valves, and municipal wastewater outfalls. Canada's potential for low head hydro has been estimated at 5000 MW at 2000 different sites across the country. Sites of up to 50 MW have been identified in Ontario and Manitoba. This study performed a market assessment on low head hydro developments. Available and emerging technologies for developing low head hydro were identified. The economics of low head hydro in Canada were explored, and barriers to low head hydro development were identified. Strategies to promote low head hydro development were also explored, and the impact of different incentive types on the low head hydropower market were estimated using a simple economic model. It was concluded that a reduced, streamlined, and standardized environmental assessment process will significantly benefit low head hydro development in Canada. 5 refs., 14 tabs., 17 figs

Prognostic impact of p53, c-erbB-2 and epidermal growth factor receptor on head and neck carcinoma

Directory of Open Access Journals (Sweden)

Orlando Parise Junior

Full Text Available CONTEXT: p53, c-erbB-2 and epidermal growth factor receptor (EGFR are cancer-related proteins that are usually expressed in head and neck squamous cell carcinoma (SCC. Their prognostic value remains controversial. OBJECTIVE: To evaluate the prognostic impact of p53, c-erbB-2 and EGFR expression in head and neck SCC. TYPE OF STUDY: Prospective. SETTING: Head and Neck Surgery Department, Hospital AC Camargo, São Paulo. METHODS: Fifty-four patients were studied for p53, c-erbB-2 and EGFR expression in head and neck SCC and adjacent mucosa, via immunohistochemistry. These data were correlated with histoclinical data and survival. RESULTS: There was a direct association of p53 expression in SCC and mucosa (p = 0.001; loss of c-erbB-2 expression (- from normal mucosa to SCC (p = 0.04; lower frequency of association of c-erbB-2 (+ with EGFR (- in SCC (p = 0.02; and a direct association of EGFR (+ expression in SCC and mitotic index (p = 0.03. The 60-month actuarial survival rates for patients presenting lymph node metastasis were higher when there was no capsule rupture by SCC (48.3%; p = 0.02, no more than one positive lymph node (52.3%; p = 0.004 or clear surgical margins (47.0%; p = 0.01, in comparison with patients presenting capsule rupture (20.2%, two or more positive lymph nodes (18.7% or compromised surgical margins (0.0%, respectively. Patients presenting SCC p53 (+ and EGFR (- demonstrated greater survival (75.0%; p = 0.03 than for the remaining group (33.1%. Multivariate analysis confirmed the positive impact of p53 (+ and EGFR (- on survival (p = 0.02. DISCUSSION: Associations were found for p53, c-erbB-2 and EGFR expression with histoclinical data and prognosis. Interestingly, these results suggest that loss of mucosal c-erbB-2 expression could be involved in SCC carcinogenesis; EGFR expression in SCC is related to tumor mitotic index; and presence of p53 with absence of EGFR expression in head and neck SCC may be a prognostic factor for

The impact of use of Glutamine on patients with head and neck tumors in radiotherapy and chemotherapy treatment

International Nuclear Information System (INIS)

Boligon, Caroline Schardong; Huth, Adriane

2011-01-01

Introduction: patients with head and neck neoplasia usually show malnutrition or a nutritional risk, because of common symptoms like: dysphagia, odynophagia and xerostomia. Objective: this study aimed to verify the impact of using amino glutamine in patients with head and neck neoplasia and under radiotherapy and chemotherapy treatment concomitantly. Methods: the research was quantitative, cross-sectional, descriptive and exploratory. The data was collected from nutritional evaluation, and patients chart consultation. The patients were divided in a control group (without use of glutamine) and a test group (with use of glutamine). 16 patients, 13 of which were men and three were women, participated in the research. Results: The control group presented mucositis grades I to IV while patients who used the amino glutamine showed mucositis grades I to II only. It could be observed that the Nutritional Risk Index decreased, which represents higher nutritional risk in patients from the control group only. In patients who used glutamine, this decrease was not significant. Conclusion: these results suggest that the use of glutamine in patients with head and neck tumors and under antineoplastic therapy helps to maintain their nutritional stage and to prevent mucositis throughout their treatment, mainly grades III and IV, which prevents adequate and regular eating and nourishment. (author)

Moneyball for Head Start: Using Data, Evidence, and Evaluation to Improve Outcomes for Children and Families

Science.gov (United States)

Mead, Sara; Mitchel, Ashley LiBetti

2016-01-01

Head Start is a valuable federal program that improves the lives of our nation's most vulnerable children and their families. Research shows that Head Start programs improve children's learning at school entry and have a positive impact on long-term life outcomes. Research also suggests that Head Start could have a stronger impact on children's…

Automatic annotation of head velocity and acceleration in Anvil

DEFF Research Database (Denmark)

Jongejan, Bart

2012-01-01

We describe an automatic face tracker plugin for the ANVIL annotation tool. The face tracker produces data for velocity and for acceleration in two dimensions. We compare the annotations generated by the face tracking algorithm with independently made manual annotations for head movements....... The annotations are a useful supplement to manual annotations and may help human annotators to quickly and reliably determine onset of head movements and to suggest which kind of head movement is taking place....

Administrative Strategies of Departmental Heads as Determinants for the Effective Management of Human Resources in Tertiary Institutions in Delta State, Nigeria

Science.gov (United States)

Osakwe, Regina N.

2015-01-01

This study investigated administrative strategies of departmental heads as determinants of effective management of human resources in tertiary institutions. Four research questions were asked and four hypotheses were formulated to guide the study. As a descriptive survey, the population comprised all the eight tertiary institutions in the state…

Do stigma and its psychosocial impact differ between Asian-born Chinese immigrants and Western-born Caucasians with head and neck cancer?

Science.gov (United States)

Lebel, Sophie; Payne, Ada Y M; Mah, Kenneth; Irish, Jonathan; Rodin, Gary; Devins, Gerald M

2016-07-01

Stigma appears to influence emotional distress and well-being in cancer survivors, but cross-cultural differences have been ignored. Previous studies suggest that stigma may be especially relevant for survivors of Asian origin. However, their study designs (e.g. focused on female cancers, qualitative designs, and an absence of comparison groups) limit the strength of this conclusion. We hypothesized that (1) Asian-born Chinese immigrants (AI) would report more perceived cancer-related stigma than Western-born Caucasians (WBC); and (2) the impact of stigma on emotional distress and well-being would be greater in AI as compared to WBC. Head and neck cancer survivors (n = 118 AI and n = 404 WBC) completed measures of well-being, emotional distress, and a three-item indicator of stigma in structured interviews. The majority of respondents (59%) reported one or more indicators of stigma. Stigma correlated significantly with emotional distress (r = .13, p = .004) and well-being (r = -.09, p = .032). Contrary to our hypotheses, WBCs and AIs did not differ in reported stigma nor did we detect differences in its psychosocial impact. Stigma exerts a deleterious psychosocial impact on head and neck cancer survivors. It did not differ significantly between AI and WBC survivors.

The threshold force required for femoral impaction grafting in revision hip surgery.

LENUS (Irish Health Repository)

Flannery, Olivia M

2010-06-01

BACKGROUND AND PURPOSE: Femoral impaction grafting requires vigorous impaction to obtain adequate stability without risk of fracture, but the force of impaction has not been determined. We determined this threshold force in a preliminary study using animal femurs. METHODS: Adult sow femurs were used because of their morphological similarity to human femurs in revision hip arthroplasty. 35 sow femurs were impacted with morselized bone chips and an increasing force was applied until the femur fractured. This allowed a threshold force to be established. 5 other femurs were impacted to this force and an Exeter stem was cemented into the neomedullary canal. A 28-mm Exeter head was attached and loaded by direct contact with a hydraulic testing machine. Axial cyclic loading was performed and the position sensor of the hydraulic testing machine measured the prosthetic head subsidence. RESULTS: 29 tests were completed successfully. The threshold force was found to be 4 kN. There was no statistically significant correlation between the load at fracture and the cortex-to-canal ratio or the bone mineral density. Following impaction with a maximum force of 4 kN, the average axial subsidence was 0.28 mm. INTERPRETATION: We achieved a stable construct without fracture. Further studies using human cadaveric femurs should be done to determine the threshold force required for femoral impaction grafting in revision hip surgery.

Impaction Force Influences Taper-Trunnion Stability in Total Hip Arthroplasty.

Science.gov (United States)

Danoff, Jonathan R; Longaray, Jason; Rajaravivarma, Raga; Gopalakrishnan, Ananthkrishnan; Chen, Antonia F; Hozack, William J

2018-01-31

This study investigated the influence of femoral head impaction force, number of head strikes, the energy sequence of head strikes, and head offset on the strength of the taper-trunnion junction. Thirty titanium-alloy trunnions were mated with 36-mm zero-offset cobalt-chromium femoral heads of corresponding taper angle. A drop tower impacted the head with 2.5J or 8.25J, resulting in 6 kN or 14 kN impaction force, respectively, in a single strike or combinations of 6 kN + 14 kN or 14 kN + 14 kN. In addition, ten 36-mm heads with -5 and +5 offset were impacted with sequential 14 kN + 14 kN strikes. Heads were subsequently disassembled using a screw-driven mechanical testing frame, and peak distraction force was recorded. Femoral head pull-off force was 45% the strike force, and heads struck with a single 14 kN impact showed a pull-off force twice that of the 6 kN group. Two head strikes with the same force did not improve pull-off force for either 6 kN (P = .90) or 14 kN (P = .90). If the forces of the 2 impactions varied, but either impact measured 14 kN, a 51% higher pull-off force was found compared to impactions of either 6 kN or 6 kN + 6 kN. Femoral head offset did not significantly change the pull-off force among -5, 0, and +5 heads (P = .37). Femoral head impaction force influenced femoral head trunnion-taper stability, whereas offset did not affect pull-off force. Multiple head strikes did not add additional stability, as long as a single strike achieved 14 kN force at the mallet-head impactor interface. Insufficient impaction force may lead to inadequate engagement of the trunnion-taper junction. Copyright © 2018 Elsevier Inc. All rights reserved.

BIOMECHANICS OF HEAD INJURY IN OLYMPIC TAEKWONDO AND BOXING

Science.gov (United States)

Fife, G.P.; Pieter, W.

2013-01-01

Objective The purpose was to examine differences between taekwondo kicks and boxing punches in resultant linear head acceleration (RLA), head injury criterion (HIC15), peak head velocity, and peak foot and fist velocities. Data from two existing publications on boxing punches and taekwondo kicks were compared. Methods For taekwondo head impacts a Hybrid II Crash Dummy (Hybrid II) head was instrumented with a tri-axial accelerometer mounted inside the Hybrid II head. The Hybrid II was fixed to a height-adjustable frame and fitted with a protective taekwondo helmet. For boxing testing, a Hybrid III Crash Dummy head was instrumented with an array of tri-axial accelerometers mounted at the head centre of gravity. Results Differences in RLA between the roundhouse kick (130.11±51.67 g) and hook punch (71.23±32.19 g, d = 1.39) and in HIC15 (clench axe kick: 162.63±104.10; uppercut: 24.10±12.54, d = 2.29) were observed. Conclusions Taekwondo kicks demonstrated significantly larger magnitudes than boxing punches for both RLA and HIC. PMID:24744497

Validation of a noninvasive system for measuring head acceleration for use during boxing competition.

Science.gov (United States)

Beckwith, Jonathan G; Chu, Jeffrey J; Greenwald, Richard M

2007-08-01

Although the epidemiology and mechanics of concussion in sports have been investigated for many years, the biomechanical factors that contribute to mild traumatic brain injury remain unclear because of the difficulties in measuring impact events in the field. The purpose of this study was to validate an instrumented boxing headgear (IBH) that can be used to measure impact severity and location during play. The instrumented boxing headgear data were processed to determine linear and rotational acceleration at the head center of gravity, impact location, and impact severity metrics, such as the Head Injury Criterion (HIC) and Gadd Severity Index (GSI). The instrumented boxing headgear was fitted to a Hybrid III (HIII) head form and impacted with a weighted pendulum to characterize accuracy and repeatability. Fifty-six impacts over 3 speeds and 5 locations were used to simulate blows most commonly observed in boxing. A high correlation between the HIII and instrumented boxing headgear was established for peak linear and rotational acceleration (r2= 0.91), HIC (r2 = 0.88), and GSI (r2 = 0.89). Mean location error was 9.7 +/- 5.2 masculine. Based on this study, the IBH is a valid system for measuring head acceleration and impact location that can be integrated into training and competition.

Development of Realistic Head Models for Electromagnetic Source Imaging of the Human Brain

National Research Council Canada - National Science Library

Akalin, Z

2001-01-01

In this work, a methodology is developed to solve the forward problem of electromagnetic source imaging using realistic head models, For this purpose, first segmentation of the 3 dimensional MR head...

Passive Cushiony Biomechanics of Head Protection in Falling Geckos

Directory of Open Access Journals (Sweden)

Hao Wang

2018-01-01

Full Text Available Gekko geckos are capable to crawl on the steep even on upside-down surfaces. Such movement, especially at great altitude, puts them at high risks of incidentally dropping down and inevitable body or head impactions, though they may trigger air-righting reaction (ARR to attenuate the landing shocks. However, the air-righting ability (ARA in Gekko geckos is not fully developed. The implementation of ARR in some geckos is quite slow; and for those without tails, the ARR is even unobservable. Since ARA is compromised in Gekko geckos, there must be some other mechanisms responsible for protecting them from head injuries during falls. In this study, we looked into a Gekko gecko’s brain to study its internal environment and structure, using the magnetic resonance imaging (MRI technique. The results showed that the brain parenchyma was fully surrounded by the cerebrospinal fluid (CSF in the skull. A succulent characteristic was presented, which meant the intracalvarium was significantly occupied by the CSF, up to 45% in volume. Then a simplified three-dimensional finite element model was built, and a dynamic simulation was conducted to evaluate the mechanical property of this succulent characteristic during the head impactions. These implied the succulent characteristic may play certain roles on the self-protection in case of head impaction, which is adaptable to the Gekko gecko’s locomotion and behavior.

The dosimetric impact of dental implants on head-and-neck volumetric modulated arc therapy

International Nuclear Information System (INIS)

Lin, Mu-Han; Li Jinsheng; Price, Robert A Jr; Wang Lu; Ma, C-M; Lee, Chung-Chi

2013-01-01

This work aims to investigate the dosimetric impact of dental implants on volumetric modulated arc therapy (VMAT) for head-and-neck patients and to evaluate the effectiveness of using the material's electron-density ratio for the correction. An in-house Monte Carlo (MC) code was utilized for the dose calculation to account for the scattering and attenuation caused by the high-Z implant material. Three different dental implant materials were studied in this work: titanium, Degubond®4 and gold. The dose perturbations caused by the dental implant materials were first investigated in a water phantom with a 1 cm 3 insert. The per cent depth dose distributions of a 3 × 3 cm 2 photon field were compared with the insert material as water and the three selected dental implant materials. To evaluate the impact of the dental implant on VMAT patient dose calculation, four head-and-neck cases were selected. For each case, the VMAT plan was designed based on the artifact-corrected patient geometry using a treatment planning system (TPS) that was typically utilized for routine patient treatment. The plans were re-calculated using the MC code for five situations: uncorrected geometry, artifact-corrected geometry and artifact-corrected geometry with one of the three different implant materials. The isodose distributions and the dose–volume histograms were cross-compared with each other. To evaluate the effectiveness of using the material's electron-density ratio for dental implant correction, the implant region was set as water with the material's electron-density ratio and the calculated dose was compared with the MC simulation with the real material. The main effect of the dental implant was the severe attenuation in the downstream. The 1 cm 3 dental implant can lower the downstream dose by 10% (Ti) to 51% (Au) for a 3 × 3 cm 2 field. The TPS failed to account for the dose perturbation if the dental implant material was not precisely defined. For the VMAT patient dose

Snowboard head injury: prospective study in Chino, Nagano, for two seasons from 1995 to 1997.

Science.gov (United States)

Nakaguchi, H; Fujimaki, T; Ueki, K; Takahashi, M; Yoshida, H; Kirino, T

1999-06-01

The popularity of snowboarding has been growing rapidly throughout the world. To date, however, the risk of head injury associated with this relatively new winter sport, especially in comparison with alpine skiing, has not been well analyzed. This study was conducted to assess the risk of head injury in snowboarding and to elucidate its features in comparison with skiing head injury. We prospectively analyzed 301 cases of head injuries related to snowboarding or skiing experienced from December of 1995 to May of 1997 at our institution, which is located close to the most popular skiing areas in Japan. Of those injuries, 143 cases were snowboard related and 158 cases were ski related. In addition to appropriate medical evaluation and medical care, detailed examination was performed on every patient to determine various factors, including sex, age, skill level, cause and mechanism of the accident, and the side of impact to the head. The data are statistically analyzed to elucidate unique features of snowboard head injury. During the study period, 2.2 million snowboarders and 4.2 million skiers visited the five skiing facilities that are covered by our hospital. Thus, the incidence of head injury was 6.5 per 100,000 visits for snowboarders and 3.8 per 100,000 visits for skiers. Beginning snowboarders more frequently sustained head injuries compared with beginning skiers (60 of 142 vs. 48 of 154, p = 0.022). Likewise, frequent causes of snowboarding head injuries were fall during jumping (43 of 139 vs. 2 of 147, pskiing head injuries (1.3%). Of 11 major head injury cases, 10 were caused by occipital impact. These results indicate that snowboarders, particularly beginners, are at higher risk for head injury, frequently involving occipital impact, and could lead to more major head injuries. We propose that measures should be taken to protect the head, especially the occiput, in snowboarding.

Modeling heading and path perception from optic flow in the case of independently moving objects

Science.gov (United States)

Raudies, Florian; Neumann, Heiko

2013-01-01

Humans are usually accurate when estimating heading or path from optic flow, even in the presence of independently moving objects (IMOs) in an otherwise rigid scene. To invoke significant biases in perceived heading, IMOs have to be large and obscure the focus of expansion (FOE) in the image plane, which is the point of approach. For the estimation of path during curvilinear self-motion no significant biases were found in the presence of IMOs. What makes humans robust in their estimation of heading or path using optic flow? We derive analytical models of optic flow for linear and curvilinear self-motion using geometric scene models. Heading biases of a linear least squares method, which builds upon these analytical models, are large, larger than those reported for humans. This motivated us to study segmentation cues that are available from optic flow. We derive models of accretion/deletion, expansion/contraction, acceleration/deceleration, local spatial curvature, and local temporal curvature, to be used as cues to segment an IMO from the background. Integrating these segmentation cues into our method of estimating heading or path now explains human psychophysical data and extends, as well as unifies, previous investigations. Our analysis suggests that various cues available from optic flow help to segment IMOs and, thus, make humans' heading and path perception robust in the presence of such IMOs. PMID:23554589

Brain tissue analysis of impacts to American football helmets.

Science.gov (United States)

Post, Andrew; Kendall, Marshall; Cournoyer, Janie; Karton, Clara; Oeur, R Anna; Dawson, Lauren; Hoshizaki, T Blaine

2018-02-01

Concussion in American football is a prevalent concern. Research has been conducted examining frequencies, location, and thresholds for concussion from impacts. Little work has been done examining how impact location may affect risk of concussive injury. The purpose of this research was to examine how impact site on the helmet and type of impact, affects the risk of concussive injury as quantified using finite element modelling of the human head and brain. A linear impactor was used to impact a helmeted Hybrid III headform in several locations and using centric and non-centric impact vectors. The resulting dynamic response was used as input for the Wayne State Brain Injury Model to determine the risk of concussive injury by utilizing maximum principal strain as the predictive variable. The results demonstrated that impacts that occur primarily to the side of the head resulted in higher magnitudes of strain in the grey and white matter, as well as the brain stem. Finally, commonly worn American football helmets were used in this research and significant risk of injury was incurred for all impacts. These results suggest that improvements in American football helmets are warranted, in particular for impacts to the side of the helmet.

The Effect of Soil Type and Moisture Content on Head Impacts on Natural Grass Athletic Fields

Directory of Open Access Journals (Sweden)

Kyley Dickson

2018-02-01

Full Text Available Studies are warranted to evaluate head injury criterion (HIC on athletic fields to determine baseline numbers and compare those findings to current critical thresholds for impact attenuation. A two year (2016 and 2017 study was conducted on University of Tennessee athletic fields (Knoxville, TN, USA to determine the effect of soil type (cohesive soil, United States Golf Association sand specifications and grass species (Poa pratensis and Cynodon dactylon × C. transvaalensis on HIC. Additionally soil moisture conditions monitored were: dry (0.06–0.16 m3/m3, acceptable (0.17–0.29 m3/m3, and wet (0.30–0.40 m3/m3. A linear relationship (r = 0.91 was identified between drop height (0.5–2.9 M and HIC value (35-1423 HIC on granular root zones of both grass types. However, HIC on cohesive soil is a function of soil water content in addition to drop height. These results demonstrate to aid in head injury prevention on cohesive soil athletic fields the HIC can be lowered by managing soil water content.

Preference Bias of Head Orientation in Choosing between Two Non-durables

Directory of Open Access Journals (Sweden)

Hiroyuki eFunaya

2015-06-01

Full Text Available The goal of this study is to investigate how customers’ gaze, head and body orientations reflect their choices. Although the relationship between human choice and gaze behavior has been well studied, other behaviors such as head and body are unknown. We conducted a two-alternatives-forced-choice task to examine (1 whether preference bias, i.e. a positional bias in gaze, head and body toward the item that was later chosen, exists in choice, (2 when preference bias is observed and when prediction of the resulting choice becomes possible (3 whether human choice is affected when the body orientations are manipulated. We used real non-durable products (cheap snacks and clothing on a shopping shelf. The results showed that there was a significant preference bias in head orientation at the beginning one second when the subjects stood straight toward the shelf, and that the head orientation was more biased toward the selected item than the gaze and the center of pressure at the ending one second. Manipulating body orientation did not affect the result of choice. The preference bias detected by observing the head orientation would be useful in marketing science for predicting customers’ choice.

Preference bias of head orientation in choosing between two non-durables.

Science.gov (United States)

Funaya, Hiroyuki; Shibata, Tomohiro

2015-01-01

The goal of this study is to investigate how customers' gaze, head and body orientations reflect their choices. Although the relationship between human choice and gaze behavior has been well-studied, other behaviors such as head and body are unknown. We conducted a two-alternatives-forced-choice task to examine (1) whether preference bias, i.e., a positional bias in gaze, head and body toward the item that was later chosen, exists in choice, (2) when preference bias is observed and when prediction of the resulting choice becomes possible (3) whether human choice is affected when the body orientations are manipulated. We used real non-durable products (cheap snacks and clothing) on a shopping shelf. The results showed that there was a significant preference bias in head orientation at the beginning 1 s when the subjects stood straight toward the shelf, and that the head orientation was more biased toward the selected item than the gaze and the center of pressure at the ending 1 s. Manipulating body orientation did not affect the result of choice. The preference bias detected by observing the head orientation would be useful in marketing science for predicting customers' choice.

Head injury in children

International Nuclear Information System (INIS)

Sugiura, Makoto; Mori, Nobuhiko; Yokosuka, Reiko; Yamamoto, Masaaki; Imanaga, Hirohisa

1981-01-01

Findings of computerized tomography (CT) in 183 cases of head injury in children were investigated with special reference to CT findings of mild head injury. As was expected, CT findings of mild head injury fell within the normal range, in almost all cases. However, abnormal findings were noticed in 4 out of 34 cases (12%) in acute stage and 7 out of 76 cases (9%) in chronic stage. They were 3 cases of localized low density area in acute stage and 6 cases of mild cerebral atrophy in chronic stage, etc. There were some cases of mild head injury in which CT findings were normal while EEG examination revealed abnormality. Also in some cases, x-ray study demonstrated linear skull fracture which CT failed to show. These conventional techniques could be still remained as useful adjunct aid in diagnosis of head injury. CT findings of cases of cerebral contusion in their acute stage were divided as follows; normal, low density, small ventricle and ventricular and/or cisternal hemorrhage, frequency of incidence being 38, 17, 22, 11% respectively. These findings were invariably converted to cerebral atrophy from 10 days to 2 months after the impacts. In the cases with intracranial hematoma revealed by CT, only 32% of them showed clinical signs of Araki's type IV in their acute stage and 63% of them showed no neurological defects, that is Araki's type I and II. A case of extreme diffuse cerebral atrophy which followed acute subdural hematoma caused by tear of bridging veins without cortical contusion was presented. (author)

Muscle tension increases impact force but decreases energy absorption and pain during visco-elastic impacts to human thighs.

Science.gov (United States)

Tsui, Felix; Pain, Matthew T G

2018-01-23

Despite uncertainty of its exact role, muscle tension has shown an ability to alter human biomechanical response and may have the ability to reduce impact injury severity. The aim of this study was to examine the effects of muscle tension on human impact response in terms of force and energy absorbed and the subjects' perceptions of pain. Seven male martial artists had a 3.9 kg medicine ball dropped vertically from seven different heights, 1.0-1.6 m in equal increments, onto their right thigh. Subjects were instructed to either relax or tense the quadriceps via knee extension (≥60% MVC) prior to each impact. F-scan pressure insoles sampling at 500 Hz recorded impact force and video was recorded at 1000 Hz to determine energy loss from the medicine ball during impact. Across all impacts force was 11% higher, energy absorption was 15% lower and time to peak force was 11% lower whilst perceived impact intensity was significantly lower when tensed. Whether muscle is tensed or not had a significant and meaningful effect on perceived discomfort. However, it did not relate to impact force between conditions and so tensing may alter localised injury risk during human on human type impacts. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Impact of Radiation Treatment Time on Survival in Patients With Head and Neck Cancer

International Nuclear Information System (INIS)

Shaikh, Talha; Handorf, Elizabeth A.; Murphy, Colin T.; Mehra, Ranee; Ridge, John A.; Galloway, Thomas J.

2016-01-01

Purpose: To assess the impact of radiation treatment time (RTT) in head and neck cancers on overall survival (OS) in the era of chemoradiation. Methods and Materials: Patients with diagnoses of tongue, hypopharynx, larynx, oropharynx, or tonsil cancer were identified by use of the National Cancer Database. RTT was defined as date of first radiation treatment to date of last radiation treatment. In the definitive setting, prolonged RTT was defined as >56 days, accelerated RTT was defined as 49 days, accelerated RTT was defined as <40 days, and standard RTT was defined as 40 to 49 days. We used χ"2 tests to identify predictors of RTT. The Kaplan-Meier method was used to compare OS among groups. Cox proportional hazards model was used for OS analysis in patients with known comorbidity status. Results: 19,531 patients were included; 12,987 (67%) had a standard RTT, 4,369 (34%) had an accelerated RTT, and 2,165 (11%) had a prolonged RTT. On multivariable analysis, accelerated RTT (hazard ratio [HR] 0.84; 95% confidence interval [CI] 0.73-0.97) was associated with an improved OS, and prolonged RTT (HR 1.25; 95% CI 1.14-1.37) was associated with a worse OS relative to standard RTT. When the 9,200 (47%) patients receiving definitive concurrent chemoradiation were examined, prolonged RTT (HR 1.29; 95% CI 1.11-1.50) was associated with a worse OS relative to standard RTT, whereas there was no significant association between accelerated RTT and OS (HR 0.76; 95% CI 0.57-1.01). Conclusion: Prolonged RTT is associated with worse OS in patients receiving radiation therapy for head and neck cancer, even in the setting of chemoradiation. Expeditious completion of radiation should continue to be a quality metric for the management of head and neck malignancies.

The Relationship between Robot's Nonverbal Behaviour and Human's Likability Based on Human's Personality.

Science.gov (United States)

Thepsoonthorn, Chidchanok; Ogawa, Ken-Ichiro; Miyake, Yoshihiro

2018-05-30

At current state, although robotics technology has been immensely developed, the uncertainty to completely engage in human-robot interaction is still growing among people. Many current studies then started to concern about human factors that might influence human's likability like human's personality, and found that compatibility between human's and robot's personality (expressions of personality characteristics) can enhance human's likability. However, it is still unclear whether specific means and strategy of robot's nonverbal behaviours enhances likability from human with different personality traits and whether there is a relationship between robot's nonverbal behaviours and human's likability based on human's personality. In this study, we investigated and focused on the interaction via gaze and head nodding behaviours (mutual gaze convergence and head nodding synchrony) between introvert/extravert participants and robot in two communication strategies (Backchanneling and Turn-taking). Our findings reveal that the introvert participants are positively affected by backchanneling in robot's head nodding behaviour, which results in substantial head nodding synchrony whereas the extravert participants are positively influenced by turn-taking in gaze behaviour, which leads to significant mutual gaze convergence. This study demonstrates that there is a relationship between robot's nonverbal behaviour and human's likability based on human's personality.

Design and fabrication of a realistic anthropomorphic heterogeneous head phantom for MR purposes.

Directory of Open Access Journals (Sweden)

Sossena Wood

Full Text Available The purpose of this study is to design an anthropomorphic heterogeneous head phantom that can be used for MRI and other electromagnetic applications.An eight compartment, physical anthropomorphic head phantom was developed from a 3T MRI dataset of a healthy male. The designed phantom was successfully built and preliminarily evaluated through an application that involves electromagnetic-tissue interactions: MRI (due to it being an available resource. The developed phantom was filled with media possessing electromagnetic constitutive parameters that correspond to biological tissues at ~297 MHz. A preliminary comparison between an in-vivo human volunteer (based on whom the anthropomorphic head phantom was created and various phantoms types, one being the anthropomorphic heterogeneous head phantom, were performed using a 7 Tesla human MRI scanner.Echo planar imaging was performed and minimal ghosting and fluctuations were observed using the proposed anthropomorphic phantom. The magnetic field distributions (during MRI experiments at 7 Tesla and the scattering parameter (measured using a network analyzer were most comparable between the anthropomorphic heterogeneous head phantom and an in-vivo human volunteer.The developed anthropomorphic heterogeneous head phantom can be used as a resource to various researchers in applications that involve electromagnetic-biological tissue interactions such as MRI.

Head Start at ages 3 and 4 versus Head Start followed by state pre-k: Which is more effective?

Science.gov (United States)

Jenkins, Jade Marcus; Farkas, George; Duncan, Greg J.; Burchinal, Margaret; Vandell, Deborah Lowe

2016-01-01

As policy-makers contemplate expanding preschool opportunities for low-income children, one possibility is to fund two, rather than one year of Head Start for children at ages 3 and 4. Another option is to offer one year of Head Start followed by one year of pre-k. We ask which of these options is more effective. We use data from the Oklahoma pre-k study to examine these two ‘pathways’ into kindergarten using regression discontinuity to estimate the effects of each age-4 program, and propensity score weighting to address selection. We find that children attending Head Start at age 3 develop stronger pre-reading skills in a high quality pre-kindergarten at age 4 compared with attending Head Start at age 4. Pre-k and Head Start were not differentially linked to improvements in children’s pre-writing skills or pre-math skills. This suggests that some impacts of early learning programs may be related to the sequencing of learning experiences to more academic programming. PMID:27076692

Czechoslovak Marxist humanism and the revolution

Czech Academy of Sciences Publication Activity Database

Mervart, Jan

2017-01-01

Roč. 69, č. 1 (2017), s. 111-126 ISSN 0925-9392 R&D Projects: GA ČR(CZ) GA16-23584S Institutional support: RVO:67985955 Keywords : Czechoslovakia * Marxist humanism * Revolution * Karel Kosík * Robert Kalivoda Subject RIV: AB - History OBOR OECD: History (history of science and technology to be 6.3, history of specific sciences to be under the respective headings) Impact factor: 0.059, year: 2016

Impact of HPV in Oropharyngeal Cancer

Directory of Open Access Journals (Sweden)

Linda Marklund

2011-01-01

Full Text Available The incidence of oropharyngeal cancers has increased in the western world and Human Papilloma Virus (HPV has been recognised as a risk factor in the last decades. During the same period the prevalence of HPV in oropharyngeal tumours has increased and HPV has been suggested responsible for the increase. The HPV-positive tumours are today recognized as a distinct subset of head and neck cancers with its own clinopathological and risk profile and have a significantly improved prognosis regardless of treatment strategy. This review summarizes current knowledge regarding human papillomavirus biology, oncogenic mechanisms, risk factors, and impact of treatment.

Visual perception of axes of head rotation

Science.gov (United States)

Arnoldussen, D. M.; Goossens, J.; van den Berg, A. V.

2013-01-01

Registration of ego-motion is important to accurately navigate through space. Movements of the head and eye relative to space are registered through the vestibular system and optical flow, respectively. Here, we address three questions concerning the visual registration of self-rotation. (1) Eye-in-head movements provide a link between the motion signals received by sensors in the moving eye and sensors in the moving head. How are these signals combined into an ego-rotation percept? We combined optic flow of simulated forward and rotational motion of the eye with different levels of eye-in-head rotation for a stationary head. We dissociated simulated gaze rotation and head rotation by different levels of eye-in-head pursuit. We found that perceived rotation matches simulated head- not gaze-rotation. This rejects a model for perceived self-rotation that relies on the rotation of the gaze line. Rather, eye-in-head signals serve to transform the optic flow's rotation information, that specifies rotation of the scene relative to the eye, into a rotation relative to the head. This suggests that transformed visual self-rotation signals may combine with vestibular signals. (2) Do transformed visual self-rotation signals reflect the arrangement of the semi-circular canals (SCC)? Previously, we found sub-regions within MST and V6+ that respond to the speed of the simulated head rotation. Here, we re-analyzed those Blood oxygenated level-dependent (BOLD) signals for the presence of a spatial dissociation related to the axes of visually simulated head rotation, such as have been found in sub-cortical regions of various animals. Contrary, we found a rather uniform BOLD response to simulated rotation along the three SCC axes. (3) We investigated if subject's sensitivity to the direction of the head rotation axis shows SCC axes specifcity. We found that sensitivity to head rotation is rather uniformly distributed, suggesting that in human cortex, visuo-vestibular integration is

Visual perception of axes of head rotation

Directory of Open Access Journals (Sweden)

David Mattijs Arnoldussen

2013-02-01

Full Text Available Registration of ego-motion is important to accurately navigate through space. Movements of the head and eye relative to space are registered through the vestibular system and optical flow, respectively. Here, we address three questions concerning the visual registration of self-rotation. 1. Eye-in-head movements provide a link between the motion signals received by sensors in the moving eye and sensors in the moving head. How are these signals combined into an ego-rotation percept? We combined optic flow of simulated forward and rotational motion of the eye with different levels of eye-in-head rotation for a stationary head. We dissociated simulated gaze rotation and head rotation by different levels of eye-in-head pursuit.We found that perceived rotation matches simulated head- not gaze-rotation. This rejects a model for perceived self-rotation that relies on the rotation of the gaze line. Rather, eye-in-head signals serve to transform the optic flow’s rotation information, that specifies rotation of the scene relative to the eye, into a rotation relative to the head. This suggests that transformed visual self-rotation signals may combine with vestibular signals.2. Do transformed visual self-rotation signals reflect the arrangement of the semicircular canals (SCC? Previously, we found sub-regions within MST and V6+ that respond to the speed of the simulated head rotation. Here, we re-analyzed those BOLD signals for the presence of a spatial dissociation related to the axes of visually simulated head rotation, such as have been found in sub-cortical regions of various animals. Contrary, we found a rather uniform BOLD response to simulated rotation along the three SCC axes.3. We investigated if subject’s sensitivity to the direction of the head rotation axis shows SCC axes specifcity. We found that sensitivity to head rotation is rather uniformly distributed, suggesting that in human cortex, visuo-vestibular integration is not arranged into

Outcome impact and cost-effectiveness of quality assurance for radiotherapy planned for the EORTC 22071-24071 prospective study for head and neck cancer

NARCIS (Netherlands)

Weber, Damien C.; Hurkmans, Coen W.; Melidis, Christos; Budach, Wilfried; Langendijk, Johannes H.; Peters, Lester J.; Gregoire, Vincent; Maingon, Philippe; Combescure, Christophe

Introduction: One of the goals of Quality Assurance in Radiotherapy (QART) is to reduce the variability and uncertainties related to treatment planning and beam delivery. The purpose of this study was to assess the outcome impact and cost-effectiveness (CE) of various QART levels for a head and neck

Spanish Instruction in Head Start and Dual Language Learners' Academic Achievement.

Science.gov (United States)

Miller, Elizabeth B

2017-09-01

Data from the Head Start Impact Study ( N = 1,141) and the Head Start Family and Child Experiences Survey, 2009 Cohort ( N = 825) were used to investigate whether Spanish instruction in Head Start differentially increased Spanish-speaking Dual Language Learners' (DLLs) academic achievement. Although hypothesized that Spanish instruction would be beneficial for DLLs' early literacy and math skills, results from residualized growth models showed there were no such positive associations. Somewhat surprisingly, DLL children instructed in Spanish had higher English receptive vocabulary skills at the end of the Head Start year than those not instructed, with children randomly assigned to Head Start and instructed in Spanish having the highest scores. Policy implications for Head Start-eligible Spanish-speaking DLLs are discussed.

Heads Up

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... Connect with Us HEADS UP Apps Reshaping the Culture Around Concussion in Sports Get HEADS UP on Your Web Site Concussion ... HEADS UP on your web site! Create a culture of safety for young athletes Officials, learn how you can ... UP to Providers HEADS UP to Youth Sports HEADS UP to School Sports HEADS UP to ...

Simultaneous transcranial direct current stimulation (tDCS) and whole-head magnetoencephalography (MEG): assessing the impact of tDCS on slow cortical magnetic fields.

Science.gov (United States)

Garcia-Cossio, Eliana; Witkowski, Matthias; Robinson, Stephen E; Cohen, Leonardo G; Birbaumer, Niels; Soekadar, Surjo R

2016-10-15

Transcranial direct current stimulation (tDCS) can influence cognitive, affective or motor brain functions. Whereas previous imaging studies demonstrated widespread tDCS effects on brain metabolism, direct impact of tDCS on electric or magnetic source activity in task-related brain areas could not be confirmed due to the difficulty to record such activity simultaneously during tDCS. The aim of this proof-of-principal study was to demonstrate the feasibility of whole-head source localization and reconstruction of neuromagnetic brain activity during tDCS and to confirm the direct effect of tDCS on ongoing neuromagnetic activity in task-related brain areas. Here we show for the first time that tDCS has an immediate impact on slow cortical magnetic fields (SCF, 0-4Hz) of task-related areas that are identical with brain regions previously described in metabolic neuroimaging studies. 14 healthy volunteers performed a choice reaction time (RT) task while whole-head magnetoencephalography (MEG) was recorded. Task-related source-activity of SCFs was calculated using synthetic aperture magnetometry (SAM) in absence of stimulation and while anodal, cathodal or sham tDCS was delivered over the right primary motor cortex (M1). Source reconstruction revealed task-related SCF modulations in brain regions that precisely matched prior metabolic neuroimaging studies. Anodal and cathodal tDCS had a polarity-dependent impact on RT and SCF in primary sensorimotor and medial centro-parietal cortices. Combining tDCS and whole-head MEG is a powerful approach to investigate the direct effects of transcranial electric currents on ongoing neuromagnetic source activity, brain function and behavior. Copyright © 2015 Elsevier Inc. All rights reserved.

Modeling occupants in far-side impacts.

Science.gov (United States)

Douglas, Clay; Fildes, Brian; Gibson, Tom

2011-10-01

Far-side impacts are not part of any regulated NCAP, FMVSS, or similar test regime despite accounting for 43 percent of the seriously injured persons and 30 percent of the harm in U.S. side impact crashes. Furthermore, injuries to the head and thorax account for over half of the serious injuries sustained by occupants in far-side crashes. Despite this, there is no regulated or well-accepted anthropomorphic test device (ATD) or computer model available to investigate far-side impacts. As such, this presents an opportunity to assess a computer model that can be used to measure the effect of varying restraint parameters on occupant biomechanics in far-side impacts. This study sets out to demonstrate the modified TASS human facet model's (MOTHMO) capabilities in modeling whole-body response in far-side impacts. MOTHMO's dynamic response was compared to that of postmortem human subjects (PMHS), WorldSID, and Thor-NT in a series of far-side sled tests. The advantages, disadvantages, and differences of using MOTHMO compared to ATDs were highlighted and described in terms of model design and instrumentation. Potential applications and improvements for MOTHMO were also recommended. The results showed that MOTHMO is capable of replicating the seat belt-to-shoulder complex interaction, pelvis impacts, head displacement, neck and shoulder belt loading from inboard mounted belts, and impacts from multiple directions. Overall, the model performed better than Thor-NT and at least as well as WorldSID when compared to PMHS results. Though WorldSID and Thor-NT ATDs were capable of reproducing many of these impact loads, measuring the seat belt-to-shoulder complex interaction and thoracic deflection at multiple sites and directions was less accurately handled. This study demonstrated that MOTHMO is capable of modeling whole-body response in far-side impacts. Furthermore, MOTHMO can be used as a virtual design tool to explore the effect of varying restraint parameters on occupant

Human health impacts in the life cycle of future European electricity generation

International Nuclear Information System (INIS)

Treyer, Karin; Bauer, Christian; Simons, Andrew

2014-01-01

This paper presents Life Cycle Assessment (LCA) based quantification of the potential human health impacts (HHI) of base-load power generation technologies for the year 2030. Cumulative Greenhouse Gas (GHG) emissions per kWh electricity produced are shown in order to provide the basis for comparison with existing literature. Minimising negative impacts on human health is one of the key elements of policy making towards sustainable development: besides their direct impacts on quality of life, HHI also trigger other impacts, e.g. external costs in the health care system. These HHI are measured using the Life Cycle Impact Assessment (LCIA) methods “ReCiPe” with its three different perspectives and “IMPACT2002+”. Total HHI as well as the shares of the contributing damage categories vary largely between these perspectives and methods. Impacts due to climate change, human toxicity, and particulate matter formation are the main contributors to total HHI. Independently of the perspective chosen, the overall impacts on human health from nuclear power and renewables are substantially lower than those caused by coal power, while natural gas can have lower HHI than nuclear and some renewables. Fossil fuel combustion as well as coal, uranium and metal mining are the life cycle stages generating the highest HHI. - Highlights: • Life cycle human health impacts (HHI) due to electricity production are analysed. • Results are shown for the three ReCiPe perspectives and IMPACT2002+LCIA method. • Total HHI of nuclear and renewables are much below those of fossil technologies. • Climate change and human toxicity contribute most to total HHI. • Fossil fuel combustion and coal mining are the most polluting life cycle stages

Renewing Head Start's Promise: Invest in What Works for Disadvantaged Preschoolers

Science.gov (United States)

Mead, Sara

2014-01-01

Since Head Start's last reauthorization in 2007, the Department of Health and Human Services, which oversees Head Start, has implemented significant reforms that are improving the program. In "Renewing Head Start's Promise: Invest in What Works for Disadvantaged Preschoolers," Sara Mead offers several recommendations to enable…

Biomechanical Analysis of Human Abdominal Impact Responses and Injuries through Finite Element Simulations of a Full Human Body Model.

Science.gov (United States)

Ruan, Jesse S; El-Jawahri, Raed; Barbat, Saeed; Prasad, Priya

2005-11-01

Human abdominal response and injury in blunt impacts was investigated through finite element simulations of cadaver tests using a full human body model of an average-sized adult male. The model was validated at various impact speeds by comparing model responses with available experimental cadaver test data in pendulum side impacts and frontal rigid bar impacts from various sources. Results of various abdominal impact simulations are presented in this paper. Model-predicted abdominal dynamic responses such as force-time and force-deflection characteristics, and injury severities, measured by organ pressures, for the simulated impact conditions are presented. Quantitative results such as impact forces, abdominal deflections, internal organ stresses have shown that the abdomen responded differently to left and right side impacts, especially in low speed impact. Results also indicated that the model exhibited speed sensitive response characteristics and the compressibility of the abdomen significantly influenced the overall impact response in the simulated impact conditions. This study demonstrates that the development of a validated finite element human body model can be useful for abdominal injury assessment. Internal organ injuries, which are difficult to detect in experimental studies with human cadavers due to the difficulty of instrumentation, may be more easily identified with a validated finite element model through stress-strain analysis.

Climate change in the oceans: Human impacts and responses.

Science.gov (United States)

Allison, Edward H; Bassett, Hannah R

2015-11-13

Although it has far-reaching consequences for humanity, attention to climate change impacts on the ocean lags behind concern for impacts on the atmosphere and land. Understanding these impacts, as well as society's diverse perspectives and multiscale responses to the changing oceans, requires a correspondingly diverse body of scholarship in the physical, biological, and social sciences and humanities. This can ensure that a plurality of values and viewpoints is reflected in the research that informs climate policy and may enable the concerns of maritime societies and economic sectors to be heard in key adaptation and mitigation discussions. Copyright © 2015, American Association for the Advancement of Science.

Realistic Avatar Eye and Head Animation Using a Neurobiological Model of Visual Attention

National Research Council Canada - National Science Library

Itti, L; Dhavale, N; Pighin, F

2003-01-01

We describe a neurobiological model of visual attention and eye/head movements in primates, and its application to the automatic animation of a realistic virtual human head watching an unconstrained...

Mapping Cumulative Impacts of Human Activities on Marine Ecosystems

OpenAIRE

, Seaplan

2018-01-01

Given the diversity of human uses and natural resources that converge in coastal waters, the potential independent and cumulative impacts of those uses on marine ecosystems are important to consider during ocean planning. This study was designed to support the development and implementation of the 2009 Massachusetts Ocean Management Plan. Its goal was to estimate and visualize the cumulative impacts of human activities on coastal and marine ecosystems in the state and federal waters off of Ma...

SizeChina : A 3D Anthropometric Survey of the Chinese Head

NARCIS (Netherlands)

Ball, R.M.

2011-01-01

Problem The design of consumer products that are worn on the head relies on the availability of accurate anthropometric information describing the shape and size of the human head and face. Historical anthropometric studies with univariate data have documented the existence of shape differences

49 CFR 572.122 - Head assembly and test procedure.

Science.gov (United States)

2010-10-01

... head CG may not be less than 245 G or more than 300 G. The resultant acceleration vs. time history... and the head must be oriented to an incline of 62 ±1 deg. between the “D” plane as shown in Figure N1 and the plane of the impact surface. The 1.57 mm (0.062 in) diameter holes located on either side of...

Advances in otolaryngology-Head and neck surgery. Volume 1

International Nuclear Information System (INIS)

Myers, E.N.; Bluestone, C.D.

1987-01-01

This book consists of 14 sections. The section titles are: The impact of AIDS on otolaryngology--head and neck surgery; The management of sleep apneas and snoring; Antimicrobial agents for infections in the ear, nose, and throat--head and neck; Nasal allergy: Medical and surgical treatment; Uses of computerized tomography and magnetic resonance imaging in temporal bone imaging; Surgical management of otitis media with effusion; middle ear reconstruction: Current status; Cochlear implants: an overview; Diagnosis and management of acute facial paralysis; The use of the laser in head and neck surgery; The management and prevention of subglottic stenosis in infants and children; Management of the mass in the thyroid; Suction-assisted lipectomy of the head and neck area; and Ambulatory surgery

Advances in otolaryngology-Head and neck surgery. Volume 1

Energy Technology Data Exchange (ETDEWEB)

Myers, E.N. (Univ. of Pittsburgh School of Medicine, Pittsburgh, PA (US)); Bluestone, C.D. (Univ. of Pittsburgh, Pittsburgh, PA (US))

1987-01-01

This book consists of 14 sections. The section titles are: The impact of AIDS on otolaryngology--head and neck surgery; The management of sleep apneas and snoring; Antimicrobial agents for infections in the ear, nose, and throat--head and neck; Nasal allergy: Medical and surgical treatment; Uses of computerized tomography and magnetic resonance imaging in temporal bone imaging; Surgical management of otitis media with effusion; middle ear reconstruction: Current status; Cochlear implants: an overview; Diagnosis and management of acute facial paralysis; The use of the laser in head and neck surgery; The management and prevention of subglottic stenosis in infants and children; Management of the mass in the thyroid; Suction-assisted lipectomy of the head and neck area; and Ambulatory surgery.

Proteome reference map of Drosophila melanogaster head.

Science.gov (United States)

Lee, Tian-Ren; Huang, Shun-Hong; Lee, Chi-Ching; Lee, Hsiao-Yun; Chan, Hsin-Tzu; Lin, Kuo-Sen; Chan, Hong-Lin; Lyu, Ping-Chiang

2012-06-01

Drosophila melanogaster has been used as a genetic model organism to understand the fundamental molecular mechanisms in human biology including memory formation that has been reported involving protein synthesis and/or post-translational modification. In this study, we employed a proteomic platform based on fluorescent 2DE and MALDI-TOF MS to build a standard D. melanogaster head proteome map for proteome-proteome comparison. In order to facilitate the comparison, an interactive database has been constructed for systematically integrating and analyzing the proteomes from different conditions and further implicated to study human diseases related to D. melanogaster model. In summary, the fundamental head proteomic database and bioinformatic analysis will be useful for further elucidating the biological mechanisms such as memory formation and neurodegenerative diseases. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Life cycle human health impacts of 875 pesticides

DEFF Research Database (Denmark)

Fantke, Peter; Jolliet, Oliver

2016-01-01

present a consistent framework for characterizing human toxicological impacts associated with pesticides applied to agricultural crops in the frame of life cycle impact assessment based on state-of-the-art data and methods. Methods We combine a dynamic multicrop plant uptake model designed for evaluating......-crop combinations of 10 orders of magnitude. Conclusions Our framework is operational for use in current life cycle impact assessment models, is made available for USEtox, and closes an important gap in the assessment of human exposure to pesticides. For ready use in life cycle assessment studies, we present...... pesticide-crop combination-specific characterization factors normalized to pesticide mass applied and provide default data for application times and loss due to post-harvest food processing. When using our data, we emphasize the need to consult current pesticide regulation, since each pesticide...

Human-mediated drivers of change — impacts on coastal ...

African Journals Online (AJOL)

Human-mediated drivers of change — impacts on coastal ecosystems and marine ... of global change because they are located at the land–ocean interface and ... upwelling regimes are all being affected by human-mediated climate change.

The Impact of Human Resource Management Practices on ...

African Journals Online (AJOL)

The focus of this paper is on the impact of HRM practices on private sector organisations performance in Nigeria. Guinness Nigeria Plc is a private sector driving entity. Its human resource practices can be crucial to its performance. The purpose of this study therefore was to assess whether Guinness‟s human resource ...

Explicitly Linking Human Impact to Ecological Function in Secondary School Classrooms

Science.gov (United States)

Wyner, Yael; Becker, Johnathan; Torff, Bruce

2014-01-01

Both the old National Science Education Standards (NSES) and the recent "Next Generation Science Standards" (NGSS) devote significant resources to learning about human environmental impact. Whereas the NSES advocate learning about human environmental impact in a section apart from the science- content learning strands, the NGSS embed…

Modeling Heading and Path Perception from Optic Flow in the Case of Independently Moving Objects

Directory of Open Access Journals (Sweden)

Florian eRaudies

2013-04-01

Full Text Available Humans are usually accurate when estimating heading or path from optic flow, even in the presence of independently moving objects (IMO in an otherwise rigid scene. To invoke significant biases in perceived heading, IMOs have to be large and obscure the focus of expansion (FOE in the image plane, which is the point of approach. For the estimation of path during curvilinear self-motion no significant biases were found in the presence of IMOs. What makes humans robust in their estimation of heading or path using optic flow? We derive analytical models of optic flow for linear and curvilinear self-motion using geometric scene models. Heading biases of a linear least squares method, which builds upon these analytical models, are large, larger than those reported for humans. This motivated us to study segmentation cues that are available from optic flow. We derive models of accretion / deletion, expansion / contraction, acceleration / deceleration, local spatial curvature, and local temporal curvature, to be used as cues to segment an IMO from the background. Integrating these segmentation cues into our method of estimating heading or path now explains human psychophysical data and extends, as well as unifies, previous investigations. Our analysis suggests that various cues available from optic flow help to segment IMOs and, thus, make humans’ heading and path perception robust in the presence of such IMOs.

In a bad place: Carers of patients with head and neck cancer experiences of travelling for cancer treatment.

Science.gov (United States)

Balfe, Myles; Keohane, Kieran; O' Brien, Katie; Gooberman-Hill, Rachael; Maguire, Rebecca; Hanly, Paul; O' Sullivan, Eleanor; Sharp, Linda

2017-10-01

To explore the effect that treatment-related commuting has on carers of patients with head and neck cancer. Semi-structured interviews, thematically analysed, with 31 carers. Treatment-related commuting had a considerable impact on carers of patients with head and neck cancer, both in practical terms (economic costs, disruption) and also in psychological terms. Many carers of patients with head and neck cancer described becoming distressed by their commute. Some carers from large urban cities appeared to have hidden commuting burdens. Some carers respond to commuting stress by 'zoning out' or becoming 'like zombies'. Treatment-related travel for head and neck cancer can have significant practical and psychological impacts. Health professionals should be aware of the impacts that commuting can have on head and neck caregivers. Health services may be able to take practical steps, such as providing subsidized parking, to address head and neck carergivers' difficulties. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dynamic head-neck stabilization and modulation with perturbation bandwidth investigated using a multisegment neuromuscular model

NARCIS (Netherlands)

Happee, R. (Riender); de Bruijn, E. (Edo); Forbes, P.A. (Patrick A.); F.C.T. van der Helm (Frans C.)

2017-01-01

textabstractThe human head-neck system requires continuous stabilization in the presence of gravity and trunk motion. We investigated contributions of the vestibulocollic reflex (VCR), the cervicocollic reflex (CCR), and neck muscle co-contraction to head-in-space and head-on-trunk stabilization,

Dynamic head-neck stabilization and modulation with perturbation bandwidth investigated using a multisegment neuromuscular model

NARCIS (Netherlands)

Happee, R.; de Bruijn, E.; Forbes, P.A.; van der Helm, F.C.T.

2017-01-01

The human head-neck system requires continuous stabilization in the presence of gravity and trunk motion. We investigated contributions of the vestibulocollic reflex (VCR), the cervicocollic reflex (CCR), and neck muscle co-contraction to head-in-space and head-on-trunk stabilization, and

Abusive head trauma and accidental head injury: a 20-year comparative study of referrals to a hospital child protection team

Science.gov (United States)

John, Simon; Vincent, Andrea L; Reed, Peter

2015-01-01

Aim To describe children referred for suspected abusive head trauma (AHT) to a hospital child protection team in Auckland, New Zealand. Methods Comparative review of demographics, histories, injuries, investigations and diagnostic outcomes for referrals under 15 years old from 1991 to 2010. Results Records were available for 345 children. Referrals increased markedly (88 in the first decade, 257 in the second), but the diagnostic ratio was stable: AHT 60%, accidental or natural 29% and uncertain cause 11%. The probability of AHT was similar regardless of socio-economic status or ethnicity. In children under 2 years old with accidental head injuries (75/255, 29%) or AHT (180/255, 71%), characteristics of particular interest for AHT included no history of trauma (88/98, 90%), no evidence of impact to the head (84/93, 90%), complex skull fractures with intracranial injury (22/28, 79%), subdural haemorrhage (160/179, 89%) and hypoxic ischaemic injury (38/39, 97%). In children over 2 years old, these characteristics did not differ significantly between children with accidental head injuries (21/47, 45%) and AHT (26/47, 55%). The mortality of AHT was higher in children over 2 years old (10/26, 38%) than under 2 years (19/180, 11%). Conclusions The striking increase in referrals for AHT probably represents increasing incidence. The decision to refer a hospitalised child with a head injury for assessment for possible AHT should not be influenced by socio-economic status or ethnicity. Children over 2 years old hospitalised for AHT are usually injured by mechanisms involving impact and should be considered at high risk of death. PMID:26130384

Altered Blood Biomarker Profiles in Athletes with a History of Repetitive Head Impacts.

Directory of Open Access Journals (Sweden)

Alex P Di Battista

Full Text Available The long-term health effects of concussion and sub-concussive impacts in sport are unknown. Growing evidence suggests both inflammation and neurodegeneration are pivotal to secondary injury processes and the etiology of neurodegenerative diseases. In the present study we characterized circulating brain injury and inflammatory mediators in healthy male and female athletes according to concussion history and collision sport participation. Eighty-seven university level athletes (male, n = 60; female, n = 27 were recruited before the start of the competitive season. Athletes were healthy at the time of the study (no medications, illness, concussion or musculoskeletal injuries. Dependent variables included 29 inflammatory and 10 neurological injury analytes assessed in the peripheral blood by immunoassay. Biomarkers were statistically evaluated using partial least squares multivariate analysis to identify possible relationships to self-reported previous concussion history, number of previous concussions and collision sport participation in male and female athletes. Multiple concussions were associated with increases in peripheral MCP-1 in females, and MCP-4 in males. Collision sport participation was associated with increases in tau levels in males. These results are consistent with previous experimental and clinical findings that suggest ongoing inflammatory and cerebral injury processes after repetitive mild head trauma. However, further validation is needed to correlate systemic biomarkers to repetitive brain impacts, as opposed to the extracranial effects common to an athletic population such as exercise and muscle damage.

Computerized Virtual Reality Simulation in Preclinical Dentistry: Can a Computerized Simulator Replace the Conventional Phantom Heads and Human Instruction?

Science.gov (United States)

Plessas, Anastasios

2017-10-01

In preclinical dental education, the acquisition of clinical, technical skills, and the transfer of these skills to the clinic are paramount. Phantom heads provide an efficient way to teach preclinical students dental procedures safely while increasing their dexterity skills considerably. Modern computerized phantom head training units incorporate features of virtual reality technology and the ability to offer concurrent augmented feedback. The aims of this review were to examine and evaluate the dental literature for evidence supporting their use and to discuss the role of augmented feedback versus the facilitator's instruction. Adjunctive training in these units seems to enhance student's learning and skill acquisition and reduce the required faculty supervision time. However, the virtual augmented feedback cannot be used as the sole method of feedback, and the facilitator's input is still critical. Well-powered longitudinal randomized trials exploring the impact of these units on student's clinical performance and issues of cost-effectiveness are warranted.

Common functional correlates of head-strike behavior in the pachycephalosaur Stegoceras validum (Ornithischia, Dinosauria and combative artiodactyls.

Directory of Open Access Journals (Sweden)

Eric Snively

Full Text Available BACKGROUND: Pachycephalosaurs were bipedal herbivorous dinosaurs with bony domes on their heads, suggestive of head-butting as seen in bighorn sheep and musk oxen. Previous biomechanical studies indicate potential for pachycephalosaur head-butting, but bone histology appears to contradict the behavior in young and old individuals. Comparing pachycephalosaurs with fighting artiodactyls tests for common correlates of head-butting in their cranial structure and mechanics. METHODS/PRINCIPAL FINDINGS: Computed tomographic (CT scans and physical sectioning revealed internal cranial structure of ten artiodactyls and pachycephalosaurs Stegoceras validum and Prenocephale prenes. Finite element analyses (FEA, incorporating bone and keratin tissue types, determined cranial stress and strain from simulated head impacts. Recursive partition analysis quantified strengths of correlation between functional morphology and actual or hypothesized behavior. Strong head-strike correlates include a dome-like cephalic morphology, neurovascular canals exiting onto the cranium surface, large neck muscle attachments, and dense cortical bone above a sparse cancellous layer in line with the force of impact. The head-butting duiker Cephalophus leucogaster is the closest morphological analog to Stegoceras, with a smaller yet similarly rounded dome. Crania of the duiker, pachycephalosaurs, and bighorn sheep Ovis canadensis share stratification of thick cortical and cancellous layers. Stegoceras, Cephalophus, and musk ox crania experience lower stress and higher safety factors for a given impact force than giraffe, pronghorn, or the non-combative llama. CONCLUSIONS/SIGNIFICANCE: Anatomy, biomechanics, and statistical correlation suggest that some pachycephalosaurs were as competent at head-to-head impacts as extant analogs displaying such combat. Large-scale comparisons and recursive partitioning can greatly refine inference of behavioral capability for fossil animals.

Proteomics analyses of human optic nerve head astrocytes following biomechanical strain.

Science.gov (United States)

Rogers, Ronan S; Dharsee, Moyez; Ackloo, Suzanne; Sivak, Jeremy M; Flanagan, John G

2012-02-01

We investigate the role of glial cell activation in the human optic nerve caused by raised intraocular pressure, and their potential role in the development of glaucomatous optic neuropathy. To do this we present a proteomics study of the response of cultured, optic nerve head astrocytes to biomechanical strain, the magnitude and mode of strain based on previously published quantitative models. In this case, astrocytes were subjected to 3 and 12% stretches for either 2 h or 24 h. Proteomic methods included nano-liquid chromatography, tandem mass spectrometry, and iTRAQ labeling. Using controls for both stretch and time, a six-plex iTRAQ liquid chromatography- tandem MS (LC/MS/MS) experiment yielded 573 proteins discovered at a 95% confidence limit. The pathways included transforming growth factor β1, tumor necrosis factor, caspase 3, and tumor protein p53, which have all been implicated in the activation of astrocytes and are believed to play a role in the development of glaucomatous optic neuropathy. Confirmation of the iTRAQ analysis was performed by Western blotting of various proteins of interest including ANXA 4, GOLGA2, and αB-Crystallin.

Proteomics Analyses of Human Optic Nerve Head Astrocytes Following Biomechanical Strain*

Science.gov (United States)

Rogers, Ronan S.; Dharsee, Moyez; Ackloo, Suzanne; Sivak, Jeremy M.; Flanagan, John G.

2012-01-01

We investigate the role of glial cell activation in the human optic nerve caused by raised intraocular pressure, and their potential role in the development of glaucomatous optic neuropathy. To do this we present a proteomics study of the response of cultured, optic nerve head astrocytes to biomechanical strain, the magnitude and mode of strain based on previously published quantitative models. In this case, astrocytes were subjected to 3 and 12% stretches for either 2 h or 24 h. Proteomic methods included nano-liquid chromatography, tandem mass spectrometry, and iTRAQ labeling. Using controls for both stretch and time, a six-plex iTRAQ liquid chromatography- tandem MS (LC/MS/MS) experiment yielded 573 proteins discovered at a 95% confidence limit. The pathways included transforming growth factor β1, tumor necrosis factor, caspase 3, and tumor protein p53, which have all been implicated in the activation of astrocytes and are believed to play a role in the development of glaucomatous optic neuropathy. Confirmation of the iTRAQ analysis was performed by Western blotting of various proteins of interest including ANXA 4, GOLGA2, and αB-Crystallin. PMID:22126795

Canine spontaneous head and neck squamous cell carcinomas represent their human counterparts at the molecular level.

Directory of Open Access Journals (Sweden)

Deli Liu

2015-06-01

Full Text Available Spontaneous canine head and neck squamous cell carcinoma (HNSCC represents an excellent model of human HNSCC but is greatly understudied. To better understand and utilize this valuable resource, we performed a pilot study that represents its first genome-wide characterization by investigating 12 canine HNSCC cases, of which 9 are oral, via high density array comparative genomic hybridization and RNA-seq. The analyses reveal that these canine cancers recapitulate many molecular features of human HNSCC. These include analogous genomic copy number abnormality landscapes and sequence mutation patterns, recurrent alteration of known HNSCC genes and pathways (e.g., cell cycle, PI3K/AKT signaling, and comparably extensive heterogeneity. Amplification or overexpression of protein kinase genes, matrix metalloproteinase genes, and epithelial-mesenchymal transition genes TWIST1 and SNAI1 are also prominent in these canine tumors. This pilot study, along with a rapidly growing body of literature on canine cancer, reemphasizes the potential value of spontaneous canine cancers in HNSCC basic and translational research.

Indirect human impacts reverse centuries of carbon sequestration and salt marsh accretion.

Science.gov (United States)

Coverdale, Tyler C; Brisson, Caitlin P; Young, Eric W; Yin, Stephanie F; Donnelly, Jeffrey P; Bertness, Mark D

2014-01-01

Direct and indirect human impacts on coastal ecosystems have increased over the last several centuries, leading to unprecedented degradation of coastal habitats and loss of ecological services. Here we document a two-century temporal disparity between salt marsh accretion and subsequent loss to indirect human impacts. Field surveys, manipulative experiments and GIS analyses reveal that crab burrowing weakens the marsh peat base and facilitates further burrowing, leading to bank calving, disruption of marsh accretion, and a loss of over two centuries of sequestered carbon from the marsh edge in only three decades. Analogous temporal disparities exist in other systems and are a largely unrecognized obstacle in attaining sustainable ecosystem services in an increasingly human impacted world. In light of the growing threat of indirect impacts worldwide and despite uncertainties in the fate of lost carbon, we suggest that estimates of carbon emissions based only on direct human impacts may significantly underestimate total anthropogenic carbon emissions.

What's the risk? Identifying potential human pathogens within grey-headed flying foxes faeces.

Directory of Open Access Journals (Sweden)

Rebekah Henry

Full Text Available Pteropus poliocephalus (grey-headed flying foxes are recognised vectors for a range of potentially fatal human pathogens. However, to date research has primarily focused on viral disease carriage, overlooking bacterial pathogens, which also represent a significant human disease risk. The current study applied 16S rRNA amplicon sequencing, community analysis and a multi-tiered database OTU picking approach to identify faecal-derived zoonotic bacteria within two colonies of P. poliocephalus from Victoria, Australia. Our data show that sequences associated with Enterobacteriaceae (62.8% ± 24.7%, Pasteurellaceae (19.9% ± 25.7% and Moraxellaceae (9.4% ± 11.8% dominate flying fox faeces. Further colony specific differences in bacterial faecal colonisation patterns were also identified. In total, 34 potential pathogens, representing 15 genera, were identified. However, species level definition was only possible for Clostridium perfringens, which likely represents a low infectious risk due to the low proportion observed within the faeces and high infectious dose required for transmission. In contrast, sequences associated with other pathogenic species clusters such as Haemophilus haemolyticus-H. influenzae and Salmonella bongori-S. enterica, were present at high proportions in the faeces, and due to their relatively low infectious doses and modes of transmissions, represent a greater potential human disease risk. These analyses of the microbial community composition of Pteropus poliocephalus have significantly advanced our understanding of the potential bacterial disease risk associated with flying foxes and should direct future epidemiological and quantitative microbial risk assessments to further define the health risks presented by these animals.

Development and validation of a human biomechanical model for rib fracture and thorax injuries in blunt impact.

Science.gov (United States)

Cai, Zhihua; Lan, Fengchong; Chen, Jiqing

2015-07-01

From 1990 to approximately 50,000-120,000 people die annually of road traffic accidents in China. Traffic accidents are the main cause of death of Chinese adults aged 15-45 years. This study aimed to determine the biomechanical response and injury tolerance of the human body in traffic accidents. The subject was a 35-year-old male with a height of 170 cm, weight of 70 kg and Chinese characteristics at the 50th percentile. Geometry was generated by computed tomography and magnetic resonance imaging. A human-body biomechanical model was then developed. The model featured in great detail the main anatomical characteristics of skeletal tissues, soft tissues and internal organs, including the head, neck, shoulder, thoracic cage, abdomen, spine, pelvis, pleurae and lungs, heart, aorta, arms, legs, and other muscle tissues and skeletons. The material properties of all tissues in the human body model were obtained from the literature. Material properties were developed in the LS-DYNA code to simulate the mechanical behaviour of the biological tissues in the human body. The model was validated against cadaver responses to frontal and side impact. The predicted model response reasonably agreed with the experimental data, and the model can further be used to evaluate thoracic injury in real-world crashes. We believe that the transportation industry can use numerical models in the future to simultaneously reduce physical testing and improve automotive safety.

Three-dimensional biomimetic head model as a platform for thermal testing of protective goggles for prevention of eye injuries.

Science.gov (United States)

Friedman, Rinat; Haimy, Ayelet; Gefen, Amit; Epstein, Yoram

2018-04-22

The rate of eye injury is steadily rising during military conflicts of the century, with thermal burns being the most common type of injury to the eyes. The present study focuses on assessing the heat resistance properties of military protective goggles using three-dimensional (3D) finite element head modeling fitted with the tested protective gear. A computational thermal impact was applied onto a 3D biomimetic human head model fitted with two goggle models - sports (Type 1) and square (Type 2). The resultant temperature of the eye tissues and the thermal injury thresholds were calculated by using the modeling, hence allowing to determine the protective efficacy of the goggles objectively, in a standardized, quantitative and cost-effective manner. Both types of goggles had a dramatic protective effect on the eyes. The specific goggle geometry had no notable effect on the level of protection to the inner tissues against the thermal insult. At the skin level goggles reduced temperatures by ~64% under the impact zone, with only a mild difference (10 °C) between the goggles. Little limitations on the shape and geometry of goggles were observed and any structure of goggles can provide an adequate protection against a thermal insult (per se) to inner cranial tissues, assuming the lenses are wide and thick enough to block direct skin contact of the heat insult. It was shown that our 3D biomimetic human head model provides a practical and cost-effective tool for determining the performance level of goggles with different attributed (i.e., shapes and thermal properties). Copyright © 2018 Elsevier Ltd. All rights reserved.

Head ballistocardiogram based on wireless multi-location sensors.

Science.gov (United States)

Onizuka, Kohei; Sodini, Charles G

2015-08-01

Recently a wearable BCG monitoring technique based on an accelerometer worn at the ear was demonstrated to replace a conventional bulky BCG acquisition system. In this work, a multi-location wireless vital signs monitor was developed, and at least two common acceleration vectors correlating to sitting-BCG were found in the supine position by using head PPG signal as a reference for eight healthy human subjects. The head side amplitude in the supine position is roughly proportional to the sitting amplitude that is in turn proportional to the stroke volume. Signal processing techniques to identify J-waves in a subject having small amplitude was also developed based on the two common vectors at the head side and top.

Schneiderian membrane detachment using transcrestal hydrodynamic ultrasonic cavitational sinus lift: a human cadaver head study and histologic analysis.

Science.gov (United States)

Troedhan, Angelo; Kurrek, Andreas; Wainwright, Marcel; Jank, Siegfried

2014-08-01

Recent studies have suggested the osteogenic layer of the periosteum at the base of the sinus membrane to play a key role in bone regeneration after sinus lift procedures. Thus, atraumatic detachment of the sinus membrane with an intact periosteum seems mandatory. The present histologic study of fresh human cadaver heads investigated the detachment behavior and histologic integrity of the detached periosteum after application of the transcrestal hydrodynamic ultrasonic cavitational sinus lift (tHUCSL-INTRALIFT). A total of 15 sinuses in 8 fresh human cadaver heads were treated using tHUCSL-INTRALIFT. After surgery, they were checked macroscopically for damage to the sinus membrane and then processed for histologic inspection under light microscopy. A total of 150 histologic specimens, randomly selected from the core surgical sites, were investigated using hematoxylin-eosin (HE), Azan, and trichrome staining. None of the 150 inspected specimens showed any perforation or dissection of the periosteum from the subepithelial connective tissue and respiratory epithelium and were fully detached from the bony antrum floor. The connecting Sharpey fibers revealed to be cleanly separated from the sinus floor in all specimens. The results of the present study suggest tHUCSL-INTRALIFT should be used to perform predictable and safe detachment of the periosteum from the bony sinus floor as a prerequisite for undisturbed and successful physiologic subantral bone regeneration. Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Radiological impacts from nuclear facilities on non-human species

International Nuclear Information System (INIS)

1997-07-01

This monograph is the Proceedings of a Symposium on Radiological Impacts from Nuclear Facilities on Non-Human Species, held in Ottawa, Canada, December 1 and 2, 1996. The Symposium was held in response to the assessment of radiological impacts from nuclear facilities on non-human biota by Environment Canada and the move by Atomic Energy Control Board to include the radiological impacts in its regulatory regime. The two major goals of the Symposium were to critically evaluate the ecological risk assessment as applied to radionuclides and contribute to the wide consultation sought by the Atomic Energy Control Board on their new environmental initiatives. The series of papers presented at the Symposium discuss issues relevant to the two major objectives of the Symposium

Targeting ADAM12 in human disease: head, body or tail?

DEFF Research Database (Denmark)

Jacobsen, J; Wewer, U M

2009-01-01

) and insulin-like growth factor receptor signaling. The body of the protein (consisting of the disintegrin, cysteine-rich, and EGF-like domains) is involved in contacts with the extracellular matrix and other cells through interactions with integrins and syndecans. Finally, the tail of the protein (consisting......ADAM12/meltrin alpha is a type I transmembrane multidomain protein involved in tumor progression and other severe diseases, including osteoarthritis, and as such could be considered as a potential drug target. In addition to protease activity, ADAM12 possesses cell binding and cell signaling...... properties. This functional trinity is reflected in the structure of ADAM12, which can be divided into head, body, and tail. The head of the protein (consisting of the pro and catalytic domains) mediates processing of growth factors and cytokines and has been implicated in epidermal growth factor (EGF...

Characterizing occipital condyle loads under high-speed head rotation.

Science.gov (United States)

Pintar, Frank A; Yoganandan, Narayan; Baisden, Jamie

2005-11-01

Because of the need to evaluate anthropomorphic test device (ATD) biofidelity under high-head angular accelerations, the purpose of the present investigation was to develop appropriate instrumentation for intact post mortem human subject (PMHS) testing, validate the instrumentation, and obtain information to characterize the response of the head-neck complex under this loading scenario. A series of rigid-arm pendulum, inertially loaded ATD tests was conducted. Head and neck ATD hydraulic piston chin pull tests were conducted. Subsequently, a series of PMHS tests was conducted to derive the response of the human head-neck under high-rate chin loading. Finally, Hybrid III and THOR-NT ATD head-neck systems were evaluated under the same scenario as the PMHS. A parametric analysis for center of gravity (CG) location and accelerometer orientation determined that even small errors (+/- 3 mm or 2 degrees), produced errors in the force and moment calculations by as much as 17 %. If the moment of inertia (MOI) term was varied by 5 %, resulting moment calculations were affected by as much as 8 %. If the 5 % error in MOI was used to compute occipital condyle moments, and results compared to upper load cell derived moments, peaks differed by as much as 24 %. The head CG and mass MOI should be directly measured for each preparation to obtain accurate results. The injury run on each specimen resulted in predominantly C1-C2 separations or partial separations. The 50(th) percentile probability of AIS=2+ neck injury using tensile force was about 2400 N; for AIS=3+ neck injury the 50(th) percentile risk was about 3180 N. When inserting extension moment as the criteria, the 50(th) percentile probability of an AIS=2+ injury was 51 Nm. The AIS=3+ extension moment at the 50(th) percentile probability was 75 Nm. The new THOR-NT ATD head-neck produced more biofidelic responses with an alternate head-neck junction design compared to the Hybrid III ATD.

Impact locations and concussion outcomes in high school football player-to-player collisions.

Science.gov (United States)

Kerr, Zachary Y; Collins, Christy L; Mihalik, Jason P; Marshall, Stephen W; Guskiewicz, Kevin M; Comstock, R Dawn

2014-09-01

Little research has examined concussion outcomes in terms of impact location (ie, the area on the head in which the impact occurred). This study describes the epidemiology of concussions resulting from player-to-player collision in high school football by impact location. National High School Sports-Related Injury Surveillance Study data (2008/2009-2012/2013) were analyzed to calculate rates and describe circumstances of football concussion (eg, symptomology, symptom resolution time, return to play) resulting from player-to-player collisions by impact location (ie, front-, back-, side-, and top-of-the-head). Most concussions resulting from player-to-player collisions occurred from front-of-the-head (44.7%) and side-of-the-head (22.3%) impacts. Number of symptoms reported, prevalence of reported symptoms, symptom resolution time, and length of time to return to play were not associated with impact location. However, a larger proportion of football players sustaining concussions from top-of-the-head impacts experienced loss of consciousness (8.0%) than those sustaining concussions from impacts to other areas of the head (3.5%) (injury proportion ratio 2.3; 95% confidence interval 1.2-4.2; P = .008). Players had their head down at the time of impact in a higher proportion of concussions caused by top-of-the-head impacts (86.4%) than concussions from impacts to other areas of the head (24.0%) (injury proportion ratio 3.6; 95% confidence interval 3.2-4.0; P impact location. Recommended strategies for reducing the proportion of top-of-the-head impacts include improved education regarding tackling with proper "head-up" technique. Copyright © 2014 by the American Academy of Pediatrics.

Speaker Prediction based on Head Orientations

NARCIS (Netherlands)

Rienks, R.J.; Poppe, Ronald Walter; van Otterlo, M.; Poel, Mannes; Poel, M.; Nijholt, A.; Nijholt, Antinus

2005-01-01

To gain insight into gaze behavior in meetings, this paper compares the results from a Naive Bayes classifier, Neural Networks and humans on speaker prediction in four-person meetings given solely the azimuth head angles. The Naive Bayes classifier scored 69.4% correctly, Neural Networks 62.3% and