Foot-strike pattern and performance in a marathon
Kasmer, Mark E.; Liu, Xue-cheng; Roberts, Kyle G.; Valadao, Jason M.
2016-01-01
Purpose To: 1) determine prevalence of heel-strike in a mid-size city marathon, 2) determine if there is an association between foot-strike classification and race performance, and 3) determine if there is an association between foot-strike classification and gender. Methods Foot-strike classification (fore-foot strike, mid-foot strike, heel strike, or split-strike), gender, and rank (position in race) were recorded at the 8.1 kilometer (km) mark for 2,112 runners at the 2011 Milwaukee Lakefront Marathon. Results 1,991 runners were classified by foot-strike pattern, revealing a heel-strike prevalence of 93.67% (n=1,865). A significant difference between foot-strike classification and performance was found using a Kruskal-Wallis test (p < 0.0001), with more elite performers being less likely to heel-strike. No significant difference between foot-strike classification and gender was found using a Fisher’s exact test. Additionally, subgroup analysis of the 126 non-heel strikers found no significant difference between shoe wear and performance using a Kruskal-Wallis test. Conclusions The high prevalence of heel-striking observed in this study reflects the foot-strike pattern of the majority of mid- to long-distance runners and more importantly, may predict their injury profile based on the biomechanics of a heel strike running pattern. This knowledge can aid the clinician in the appropriate diagnosis, management, and training modifications of the injured runner. PMID:23006790
Strike Manual: Related to Potential School Employee Strike Action.
ERIC Educational Resources Information Center
Loftus, Richard J., Jr., Ed.; And Others
Strikes and threats of strikes have become one of the realities of public education. School districts must be prepared to deal with strikes and the problems that they present. This manual is designed to provide a brief overview of the law relating to public employee strikes and to assist districts in adopting their own strike plans. It offers…
Gafni-Lachter, Liat; Admi, Hanna; Eilon, Yael; Lachter, Jesse
2017-01-01
Strikes are means to influence policies related to working conditions, yet raise ethical dilemmas for healthcare workers. Nurse strikes have become more prominent around the world. To assess the change in Israeli nurses' attitudes towards strikes in light of two physician strikes that have preceded a nursing strike. An anonymous survey was administered once in 2000 (N = 106) and again in 2011 (n = 175) following 110 days of a physician strike, to assess nurses' attitudes towards the strike and resulting ethical issues. A statistically significant change (p < 0.05) between administrations revealed that in 2011 more nurses identified striking as a legitimate mechanism, would strike under the same circumstances, and felt that collaboration with physicians persisted despite the strike. Additionally, an increasing number of nurses said that the suffering of patients due to the strike is somewhat or entirely justified, although they were faced with a difficult dilemma of loyalty to physician colleagues vs. Nurses reported finding ways to mitigate the suffering of patients resulting from the strike. While patient-centered care remains nurses' first and foremost priority, findings indicate an increasing support of collective bargaining and strike to promote working conditions related to professional and public health agendas.
Foot-strike pattern and performance in a marathon.
Kasmer, Mark E; Liu, Xue-Cheng; Roberts, Kyle G; Valadao, Jason M
2013-05-01
To determine prevalence of heel strike in a midsize city marathon, if there is an association between foot-strike classification and race performance, and if there is an association between foot-strike classification and gender. Foot-strike classification (forefoot, midfoot, heel, or split strike), gender, and rank (position in race) were recorded at the 8.1-km mark for 2112 runners at the 2011 Milwaukee Lakefront Marathon. 1991 runners were classified by foot-strike pattern, revealing a heel-strike prevalence of 93.67% (n = 1865). A significant difference between foot-strike classification and performance was found using a Kruskal-Wallis test (P < .0001), with more elite performers being less likely to heel strike. No significant difference between foot-strike classification and gender was found using a Fisher exact test. In addition, subgroup analysis of the 126 non-heel strikers found no significant difference between shoe wear and performance using a Kruskal-Wallis test. The high prevalence of heel striking observed in this study reflects the foot-strike pattern of most mid-distance to long-distance runners and, more important, may predict their injury profile based on the biomechanics of a heel-strike running pattern. This knowledge can help clinicians appropriately diagnose, manage, and train modifications of injured runners.
A kinematic method for footstrike pattern detection in barefoot and shod runners.
Altman, Allison R; Davis, Irene S
2012-02-01
Footstrike patterns during running can be classified discretely into a rearfoot strike, midfoot strike and forefoot strike by visual observation. However, the footstrike pattern can also be classified on a continuum, ranging from 0% to 100% (extreme rearfoot to extreme forefoot) using the strike index, a measure requiring force plate data. When force data are not available, an alternative method to quantify the strike pattern must be used. The purpose of this paper was to quantify the continuum of foot strike patterns using an easily attainable kinematic measure, and compare it to the strike index measure. Force and kinematic data from twenty subjects were collected as they ran across an embedded force plate. Strike index and the footstrike angle were identified for the four running conditions of rearfoot strike, midfoot strike and forefoot strike, as well as barefoot. The footstrike angle was calculated as the angle of the foot with respect to the ground in the sagittal plane. Results indicated that the footstrike angle was significantly correlated with strike index. The linear regression model suggested that strike index can be accurately estimated, in both barefoot and shod conditions, in the absence of force data. Copyright © 2011 Elsevier B.V. All rights reserved.
Issues and Outcomes of Teachers' Strikes, 1955-65.
ERIC Educational Resources Information Center
Goergen, Joseph H.; Keough, John J.
This study analyzes the patterns of 40 teacher strikes between 1955 and 1965 by looking at (1) the issues and demands and (2) the outcomes and settlements. It is hypothesized that (1) teacher strikes fall into discernible patterns, (2) functional relationships exist between certain strike issues and outcomes and the strike itself, (3) strikes can…
Is the foot striking pattern more important than barefoot or shod conditions in running?
Shih, Yo; Lin, Kuan-Lun; Shiang, Tzyy-Yuang
2013-07-01
People have advocated barefoot running, claiming that it is better suited to human nature. Humans usually run barefoot using a forefoot strike and run shod using a heel strike. The striking pattern was thought to be a key factor that contributes to the benefit of barefoot running. The purpose of this study is to use scientific data to prove that the striking pattern is more important than barefoot or shod conditions for runners on running injuries prevention. Twelve habitually male shod runners were recruited to run under four varying conditions: barefoot running with a forefoot strike, barefoot running with a heel strike, shod running with a forefoot strike, and shod running with a heel strike. Kinetic and kinematic data and electromyography signals were recorded during the experiments. The results showed that the lower extremity can gain more compliance when running with a forefoot strike. Habitually shod runners can gain more shock absorption by changing the striking pattern to a forefoot strike when running with shoes and barefoot conditions. Habitually shod runners may be subject to injuries more easily when they run barefoot while maintaining their heel strike pattern. Higher muscle activity in the gastrocnemius was observed when running with a forefoot strike, which may imply a greater training load on the muscle and a tendency for injury. Copyright © 2013 Elsevier B.V. All rights reserved.
The effects of preferred and non-preferred running strike patterns on tissue vibration properties.
Enders, Hendrik; von Tscharner, Vinzenz; Nigg, Benno M
2014-03-01
To characterize soft tissue vibrations during running with a preferred and a non-preferred strike pattern in shoes and barefoot. Cross-sectional study. Participants ran at 3.5 m s(-1) on a treadmill in shoes and barefoot using a rearfoot and a forefoot strike for each footwear condition. The preferred strike patterns for the subjects were a rearfoot strike and a forefoot strike for shod and barefoot running, respectively. Vibrations were recorded with an accelerometer overlying the belly of the medial gastrocnemius. Thirteen non-linearly scaled wavelets were used for the analysis. Damping was calculated as the overall decay of power in the acceleration signal post ground contact. A higher damping coefficient indicates higher damping capacities of the soft tissue. The shod rearfoot strike showed a 93% lower damping coefficient than the shod forefoot strike (p<0.001). A lower damping coefficient indicates less damping of the vibrations. The barefoot forefoot strike showed a trend toward a lower damping coefficient compared to a barefoot rearfoot strike. Running barefoot with a forefoot strike resulted in a significantly lower damping coefficient than a forefoot strike when wearing shoes (p<0.001). The shod rearfoot strike showed lower damping compared to a barefoot rearfoot strike (p<0.001). While rearfoot striking showed lower vibration frequencies in shod and barefoot running, it did not consistently result in lower damping coefficients. This study showed that the use of a preferred movement resulted in lower damping coefficients of running related soft tissue vibrations. Copyright © 2013 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
THE EFFECT OF STEP RATE MANIPULATION ON FOOT STRIKE PATTERN OF LONG DISTANCE RUNNERS.
Allen, Darrell J; Heisler, Hollie; Mooney, Jennifer; Kring, Richard
2016-02-01
Running gait retraining to change foot strike pattern in runners from a heel strike pattern to a non heel- strike pattern has been shown to reduce impact forces and may help to reduce running related injuries. Step rate manipulation above preferred is known to help decrease step length, foot inclination angle, and vertical mass excursion, but has not yet been evaluated as a method to change foot strike pattern. The purpose of this study was to investigate the effect of step rate manipulation on foot strike pattern in shod recreational runners who run with a heel strike pattern. A secondary purpose was to describe the effect of step rate manipulation at specific percentages above preferred on foot inclination angle at initial contact. Forty volunteer runners, who were self-reported heel strikers and had a weekly running mileage of at least 10 miles, were recruited. Runners were confirmed to be heel strikers during the warm up period on the treadmill. The subject's step rate was determined at their preferred running pace. A metronome was used to increase step rate above the preferred step rate by 5%, 10% and 15%. 2D video motion analysis was utilized to determine foot strike pattern and to measure foot inclination angle at initial contact for each step rate condition. There was a statistically significant change in foot strike pattern from a heel strike pattern to a mid-foot or forefoot strike pattern at both 10% and 15% step rates above preferred. Seven of the 40 subjects (17.5%) changed from a heel- strike pattern to a non- heel strike pattern at +10% and 12 of the 40 subjects (30%) changed to a non-heel strike pattern at +15%. Mean foot inclination angle at initial contact showed a statistically significant change (reduction) as step rate increased. Step rate manipulation of 10% or greater may be enough to change foot strike pattern from a heel strike to a mid-foot or forefoot strike pattern in a small percentage of recreational runners who run in traditional running shoes. If changing the foot strike pattern is the main goal, other gait re-training methods may be needed to make a change from a heel strike to a non-heel strike pattern. Step rate manipulation shows a progressive reduction of foot inclination angle at 5%, 10%, and 15% above preferred step rate which reduces the severity of the heel strike at initial contact. Step rate manipulation of at least +10% above preferred may be an effective running gait retraining method for clinicians to decrease the severity of heel strike and possibly assist a runner to change to a non-heel strike pattern. 3.
[Neurological diseases after lightning strike : Lightning strikes twice].
Gruhn, K M; Knossalla, Frauke; Schwenkreis, Peter; Hamsen, Uwe; Schildhauer, Thomas A; Tegenthoff, Martin; Sczesny-Kaiser, Matthias
2016-06-01
Lightning strikes rarely occur but 85 % of patients have lightning-related neurological complications. This report provides an overview about different modes of energy transfer and neurological conditions related to lightning strikes. Moreover, two case reports demonstrate the importance of interdisciplinary treatment and the spectrum of neurological complications after lightning strikes.
Foot strike and injury rates in endurance runners: a retrospective study.
Daoud, Adam I; Geissler, Gary J; Wang, Frank; Saretsky, Jason; Daoud, Yahya A; Lieberman, Daniel E
2012-07-01
This retrospective study tests if runners who habitually forefoot strike have different rates of injury than runners who habitually rearfoot strike. We measured the strike characteristics of middle- and long-distance runners from a collegiate cross-country team and quantified their history of injury, including the incidence and rate of specific injuries, the severity of each injury, and the rate of mild, moderate, and severe injuries per mile run. Of the 52 runners studied, 36 (69%) primarily used a rearfoot strike and 16 (31%) primarily used a forefoot strike. Approximately 74% of runners experienced a moderate or severe injury each year, but those who habitually rearfoot strike had approximately twice the rate of repetitive stress injuries than individuals who habitually forefoot strike. Traumatic injury rates were not significantly different between the two groups. A generalized linear model showed that strike type, sex, race distance, and average miles per week each correlate significantly (P < 0.01) with repetitive injury rates. Competitive cross-country runners on a college team incur high injury rates, but runners who habitually rearfoot strike have significantly higher rates of repetitive stress injury than those who mostly forefoot strike. This study does not test the causal bases for this general difference. One hypothesis, which requires further research, is that the absence of a marked impact peak in the ground reaction force during a forefoot strike compared with a rearfoot strike may contribute to lower rates of injuries in habitual forefoot strikers.
Patellofemoral joint stress during running with alterations in foot strike pattern.
Vannatta, Charles Nathan; Kernozek, Thomas W
2015-05-01
This study aimed to quantify differences in patellofemoral joint stress that may occur when healthy runners alter their foot strike pattern from their habitual rearfoot strike to a forefoot strike to gain insight on the potential etiology and treatment methods of patellofemoral pain. Sixteen healthy female runners completed 20 running trials in a controlled laboratory setting under rearfoot strike and forefoot strike conditions. Kinetic and kinematic data were used to drive a static optimization technique to estimate individual muscle forces to input into a model of the patellofemoral joint to estimate joint stress during running. Peak patellofemoral joint stress and the stress-time integral over stance phase decreased by 27% and 12%, respectively, in the forefoot strike condition (P < 0.001). Peak vertical ground reaction force increased slightly in the forefoot strike condition (P < 0.001). Peak quadriceps force and average hamstring force decreased, whereas gastrocnemius and soleus muscle forces increased when running with a forefoot strike (P < 0.05). Knee flexion angle at initial contact increased (P < 0.001), total knee excursion decreased (P < 0.001), and no change occurred in peak knee flexion angle (P = 0.238). Step length did not change between conditions (P = 0.375), but the leading leg landed with the foot positioned with a horizontal distance closer to the hip at initial contact in the forefoot strike condition (P < 0.001). Altering one's strike pattern to a forefoot strike results in consistent reductions in patellofemoral joint stress independent of changes in step length. Thus, implementation of forefoot strike training programs may be warranted in the treatment of runners with patellofemoral pain. However, it is suggested that the transition to a forefoot strike pattern should be completed in a graduated manner.
Effect of public transport strikes on air pollution levels in Barcelona (Spain).
Basagaña, Xavier; Triguero-Mas, Margarita; Agis, David; Pérez, Noemí; Reche, Cristina; Alastuey, Andrés; Querol, Xavier
2018-01-01
Public transport strikes can lead to an increase of the number of private vehicle trips, which in turn can increase air pollution levels. We aimed to estimate the change in air pollution concentrations during public transport strikes in the city of Barcelona (Spain). Data on strikes of the metro, train or bus systems were collected from government records (2005-2016). We collected daily concentrations of NOx; particulate matter with an aerodynamic diameter smaller than 10μm (PM10), 2.5μm (PM2.5), and 1μm (PM1); particle number concentration (N); black carbon (BC) and CO from research and official monitoring stations. We fitted linear regression models for each pollutant with the strike indicator as an independent variable, and models were adjusted for day of the week, month, year, and holiday periods. During the study period, there were 208days affected by a strike of the metro (28), train (106) or bus (91) systems. Half of the strikes were partial, most of them were single-day strikes, there was little overlap between strikes of the different transport systems, and all strikes had to comply with mandatory minimal services. When pooling all types of strikes, NOx and BC showed higher levels during strike days in comparison with non-strike days (increase between 4.1% and 7.7%, with higher increases for NO). The increases in these concentrations were more evident during full day and multiday metro strikes. In conclusion, alterations in public transport have consequences on air quality. This highlights the importance of public transport in reducing air pollution concentrations in cities. Copyright © 2017 Elsevier B.V. All rights reserved.
Foot strike patterns of recreational and sub-elite runners in a long-distance road race.
Larson, Peter; Higgins, Erin; Kaminski, Justin; Decker, Tamara; Preble, Janine; Lyons, Daniela; McIntyre, Kevin; Normile, Adam
2011-12-01
Although the biomechanical properties of the various types of running foot strike (rearfoot, midfoot, and forefoot) have been studied extensively in the laboratory, only a few studies have attempted to quantify the frequency of running foot strike variants among runners in competitive road races. We classified the left and right foot strike patterns of 936 distance runners, most of whom would be considered of recreational or sub-elite ability, at the 10 km point of a half-marathon/marathon road race. We classified 88.9% of runners at the 10 km point as rearfoot strikers, 3.4% as midfoot strikers, 1.8% as forefoot strikers, and 5.9% of runners exhibited discrete foot strike asymmetry. Rearfoot striking was more common among our sample of mostly recreational distance runners than has been previously reported for samples of faster runners. We also compared foot strike patterns of 286 individual marathon runners between the 10 km and 32 km race locations and observed increased frequency of rearfoot striking at 32 km. A large percentage of runners switched from midfoot and forefoot foot strikes at 10 km to rearfoot strikes at 32 km. The frequency of discrete foot strike asymmetry declined from the 10 km to the 32 km location. Among marathon runners, we found no significant relationship between foot strike patterns and race times.
NASA Astrophysics Data System (ADS)
Nugraheni, L. R.; Niasari, S. W.; Nukman, M.
2018-04-01
Geothermal manifestations located in the Tiris, Mount Lamongan, Probolinggo, consist of warm springs. These warm springs have temperature from 35° until 45°C. Tiris fault has NW-SE dominant orientation, similar to some lineaments of maars and cinder cones around Mount Lamongan. The Mount Lamongan geothermal area is situated between Bromo and Argapura volcanoes. This study aims to map the geo-electrical and geological strikes in the study area. Phase tensor analysis has been performed in this study to determine geo-electrical strike of study area. Geological field campaign has been conducted to measure geological strikes. Then, orientation of geo-electrical strike was compared to geological strike. The result presents that the regional geological strike of study area is NW-SE while the orientation of geo-electrical strike is N-S.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-01-11
... OMX PHLX, Inc. To Amend the $1 Strike Program To Allow Low-Strike LEAPS January 4, 2010. Pursuant to... 1012 (Series of Options Open for Trading) to expand the Exchange's $1 Strike Price Program (``Program'' or ``$1 Strike Program'') \\3\\ to allow listing long-term option series (``LEAPS'') \\4\\ in $1 strike...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-03-24
...) of the Securities Exchange Act of 1934 (``Act'')\\1\\, and Rule 19b-4\\2\\ thereunder, notice is hereby... Price Program (``$1 Strike Program'').\\4\\ \\3\\ The $0.50 Strike Program was initiated in an immediately... $4 strikes for classes that participate in both the $0.50 Strike Program and the $1 Strike Program...
ERIC Educational Resources Information Center
Adavbiele, J. A.
2015-01-01
This paper was designed to x-ray the implications of incessant strike actions on the implementation of Technical education programme in Nigeria. The paper took an exploratory view on the concept of strike actions in Nigeria with particular references on notable strike actions that have occurred in Nigeria. The types of strike were explained and…
Cheung, Roy T H; Wong, Rodney Y L; Chung, Tim K W; Choi, R T; Leung, Wendy W Y; Shek, Diana H Y
2017-06-01
Compared to competitive runners, recreational runners appear to be more prone to injuries, which have been associated with foot strike patterns. Surprisingly, only few studies had examined the foot strike patterns outside laboratories. Therefore, this study compared the foot strike patterns in recreational runners at outdoor tracks with previously reported data. We also investigated the relationship between foot strike pattern, speed, and footwear in this cohort. Among 434 recreational runners analysed, 89.6% of them landed with rearfoot strike (RFS). Only 6.9 and 3.5% landed with midfoot and forefoot, respectively. A significant shift towards non-RFS was observed in our cohort, when compared with previously reported data. When speed increased by 1 m/s, the odds of having forefoot strike and midfoot strike relative to RFS increased by 2.3 times and 2.6 times, respectively. Runners were 9.2 times more likely to run with a forefoot strike in minimalists compared to regular running shoes, although 70% of runners in minimalists continued to use a RFS. These findings suggest that foot strike pattern may differ across running conditions and runners should consider these factors in order to mitigate potential injury.
Debunking the viper's strike: harmless snakes kill a common assumption.
Penning, David A; Sawvel, Baxter; Moon, Brad R
2016-03-01
To survive, organisms must avoid predation and acquire nutrients and energy. Sensory systems must correctly differentiate between potential predators and prey, and elicit behaviours that adjust distances accordingly. For snakes, strikes can serve both purposes. Vipers are thought to have the fastest strikes among snakes. However, strike performance has been measured in very few species, especially non-vipers. We measured defensive strike performance in harmless Texas ratsnakes and two species of vipers, western cottonmouths and western diamond-backed rattlesnakes, using high-speed video recordings. We show that ratsnake strike performance matches or exceeds that of vipers. In contrast with the literature over the past century, vipers do not represent the pinnacle of strike performance in snakes. Both harmless and venomous snakes can strike with very high accelerations that have two key consequences: the accelerations exceed values that can cause loss of consciousness in other animals, such as the accelerations experienced by jet pilots during extreme manoeuvres, and they make the strikes faster than the sensory and motor responses of mammalian prey and predators. Both harmless and venomous snakes can strike faster than the blink of an eye and often reach a target before it can move. © 2016 The Author(s).
Hughes, J R; Bowes, S G; Leeman, A L; O'Neill, C J; Deshmukh, A A; Nicholson, P W; Dobbs, S M; Dobbs, R J
1990-01-01
1. Normally during walking, the heel strikes the ground before the forefoot. Abnormalities of foot strike in idiopathic Parkinson's disease may be amenable to therapy: objective measurements may reveal response which is not clinically apparent. Occult changes in foot strike leading to instability may parallel the normal, age-related loss of striatal dopamine. 2. The nature of foot strike was studied using pedobarography in 160 healthy volunteers, aged 15 to 91 years. Although 16% of strikes were made simultaneously by heel and forefoot, there were no instances of the forefoot preceding the heel. No significant effect of age on an index of normality of foot strikes was detected (P greater than 0.3). 3. The effect on foot strike of substituting placebo for a morning dose of a levodopa/carbidopa combination was studied in a double-blind, cross-over trial in 14 patients, aged 64 to 88 years, with no overt fluctuations in control of their idiopathic Parkinson's disease in relation to dosing. On placebo treatment there was a highly significant (P = 0.004) reduction in the number of more normal strikes, i.e. heel strikes plus simultaneous heel and forefoot strikes. The effect appeared unrelated to the corresponding difference between active and placebo treatments in plasma concentration of levodopa or a metabolite of long half-time, 3-O-methyldopa (3OMD). However, it correlated negatively (P less than 0.05) with the mean of the 3OMD concentrations. 4. It appears that some abnormalities of foot strike due to Parkinson's disease are reversible. Employing test conditions, designed to provoke abnormalities of foot strike, might be useful in screening for pre-clinical Parkinson's disease. PMID:2306409
The effect of hand dominance on martial arts strikes.
Neto, Osmar Pinto; Silva, Jansen Henrique; Marzullo, Ana Carolina de Miranda; Bolander, Richard P; Bir, Cynthia A
2012-08-01
The main goal of this study was to compare dominant and non-dominant martial arts palm strikes under different circumstances that usually happen during martial arts and combative sports applications. Seven highly experienced (10±5 years) right hand dominant Kung Fu practitioners performed strikes with both hands, stances with left or right lead legs, and with the possibility or not of stepping towards the target (moving stance). Peak force was greater for the dominant hand strikes (1593.76±703.45 N vs. 1042.28±374.16 N; p<.001), whereas no difference was found in accuracy between the hands (p=.141). Additionally, peak force was greater for the strikes with moving stance (1448.75±686.01 N vs. 1201.80±547.98 N; p=.002) and left lead leg stance (1378.06±705.48 N vs. 1269.96±547.08 N). Furthermore, the difference in peak force between strikes with moving and stationary stances was statistically significant only for the strikes performed with a left lead leg stance (p=.007). Hand speed was higher for the dominant hand strikes (5.82±1.08 m/s vs. 5.24±0.78 m/s; p=.001) and for the strikes with moving stance (5.79±1.01 m/s vs. 5.29±0.90 m/s; p<.001). The difference in hand speed between right and left hand strikes was only significant for strikes with moving stance. In summary, our results suggest that the stronger palm strike for a right-handed practitioner is a right hand strike on a left lead leg stance moving towards the target. Copyright © 2011 Elsevier B.V. All rights reserved.
THE EFFECT OF HAND DOMINANCE ON MARTIAL ARTS STRIKES
Neto, Osmar Pinto; Silva, Jansen Henrique; de Miranda Marzullo, Ana Carolina; Bolander, Richard P.; Bir, Cynthia A.
2011-01-01
The main goal of this study was to compare dominant and non-dominant martial arts palm strikes under different circumstances that usually happen during martial arts and combative sports applications. Seven highly experienced (10 ± 5 years) right hand dominant Kung Fu practitioners performed strikes with both hands, stances with left or right lead legs, and with the possibility or not of stepping towards the target (moving stance). Peak force was greater for the dominant hand strikes (1593.76 ± 703.45 N vs. 1042.28 ± 374.16 N; p < .001), whereas no difference was found in accuracy between the hands (p = .141). Additionally, peak force was greater for the strikes with moving stance (1448.75 ± 686.01 N vs. 1201.80 ± 547.98 N; p = .002) and left lead leg stance (1378.06 ± 705.48 N vs.1269.96 ± 547.08 N). Furthermore, the difference in peak force between strikes with moving and stationary stances was statistically significant only for the strikes performed with a left lead leg stance (p = .007). Hand speed was higher for the dominant hand strikes (5.82 ± 1.08 m/s vs. 5.24 ± 0.78 m/s; p = 0.001) and for the strikes with moving stance (5.79 ± 1.01 m/s vs. 5.29 ± 0.90 m/s; p < .001). The difference in hand speed between right and left hand strikes was only significant for strikes with moving stance. In summary, our results suggest that the stronger palm strike for a right-handed practitioner is a right hand strike on a left lead leg stance moving towards the target. PMID:22047701
A decade of U.S. Air Force bat strikes
Peurach, Suzanne C.; Dove, Carla J.; Stepko, Laura
2009-01-01
From 1997 through 2007, 821 bat strikes were reported to the U.S. Air Force (USAF) Safety Center by aircraft personnel or ground crew and sent to the National Museum of Natural History, Smithsonian Institution, for identification. Many samples were identified by macroscopic and or microscopic comparisons with bat specimens housed in the museum and augmented during the last 2 years by DNA analysis. Bat remains from USAF strikes during this period were received at the museum from 40 states in the United States and from 20 countries. We confirmed that 46% of the strikes were caused by bats, but we did not identify them further; we identified 5% only to the family or genus level, and 49% to the species level. Fifty-five of the 101 bat-strike samples submitted for DNA analysis have been identified to the species level. Twenty-five bat species have been recorded striking USAF planes worldwide. The Brazilian free-tailed bat (Tadarida brasiliensis; n = 173) is the species most commonly identified in USAF strike impacts, followed by the red bat (Lasiurus borealis; n = 83). Bat strikes peak during the spring and fall, with >57% occurring from August through October; 82% of the reports that included time of strike were recorded between 2100 and 0900 hours. More than 12% of the bat strikes were reported at >300 m above ground level (AGL). Although <1% of the bat-strike reports indicated damage to USAF aircraft, cumulative damage for 1997 through 2007 totaled >$825,000 and >50% of this sum was attributable to 5 bat-strike incidents. Only 5 bats from the 10 most damaging bat strikes were identified to the species level, either because we did not receive remains with the reports or the sample was insufficient for identification.
When Push Comes to Shove: Strikes in Higher Education.
ERIC Educational Resources Information Center
Magney, John
2002-01-01
To provide a better sense of how academic unions handle a strike situation, examines six unions who, between 1996 and 2000, went through strikes. Discusses the key issues and outcomes of the strikes. (EV)
A bird strike handbook for base-level managers
NASA Astrophysics Data System (ADS)
Payson, R. P.; Vance, J. D.
1984-09-01
To help develop more awareness about bird strikes and bird strike reduction techniques, this thesis compiled all relevant information through an extensive literature search, review of base-level documents, and personal interviews. The final product--A Bird Strike Handbook for Base-Level Managers--provides information on bird strike statistics, methods to reduce the strike hazards, and means to obtain additional assistance. The handbook is organized for use by six major base agencies: Maintenance, Civil Engineering, Operations, Air Field Management, Safety, and Air Traffic Control. An appendix follows at the end.
Conventional Prompt Global Strike and Long Range Ballistic Missiles: Background and Issues
2017-02-03
Conventional Prompt Global Strike and Long-Range Ballistic Missiles: Background and Issues Amy F. Woolf Specialist in Nuclear Weapons Policy...February 3, 2017 Congressional Research Service 7-5700 www.crs.gov R41464 Conventional Prompt Global Strike and Long-Range Ballistic Missiles...Congressional Research Service Summary Conventional prompt global strike (CPGS) weapons would allow the United States to strike targets anywhere
Preemptive strikes: Fear, hope, and defensive aggression.
Halevy, Nir
2017-02-01
Preemptive strikes are costly and harmful. Existing models of defensive aggression focus narrowly on the role fear plays in motivating preemptive strikes. Theoretically integrating the literatures on conflict, decision making, and emotion, the current research investigated how specific emotions associated with certainty or uncertainty, including fear, anger, disgust, hope, and happiness, influence preemptive strikes. Study 1 demonstrated that hope negatively predicts defensive exits from relationships in choice dilemmas. Studies 2 and 3 experimentally manipulated risk of being attacked in an incentivized, interactive decision making task-the Preemptive Strike Game. Risk of being attacked fueled preemptive strikes; reduced feelings of hope partially mediated this effect in Study 3. Studies 4 and 5 investigated preemptive strikes under uncertainty (rather than risk). In Study 4, reasoning about the factors that make one trustful of others curbed preemptive strikes; cogitating about the factors that underlie discrete emotions, however, did not influence defensive aggression. Study 5 demonstrated that the valence and uncertainty appraisals of incidental emotions interact in shaping preemptive strikes. Specifically, recalling an autobiographical emotional experience that produced hope significantly decreased attack rates relative to fear, happiness, and a control condition. Fear, anger, disgust, and happiness were either unrelated to preemptive strikes or showed inconsistent relationships with preemptive strikes across the 5 studies. These findings shed light on how emotions shape defensive aggression, advance knowledge on strategic choice under risk and uncertainty, and demonstrate hope's positive effects on social interactions and relationships. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
The Effects of Height and Distance on the Force Production and Acceleration in Martial Arts Strikes
Bolander, Richard P.; Neto, Osmar Pinto; Bir, Cynthia A.
2009-01-01
Almost all cultures have roots in some sort of self defence system and yet there is relatively little research in this area, outside of a sports related environment. This project investigated different applications of strikes from Kung Fu practitioners that have not been addressed before in the literature. Punch and palm strikes were directly compared from different heights and distances, with the use of a load cell, accelerometers, and high speed video. The data indicated that the arm accelerations of both strikes were similar, although the force and resulting acceleration of the target were significantly greater for the palm strikes. Additionally, the relative height at which the strike was delivered was also investigated. The overall conclusion is that the palm strike is a more effective strike for transferring force to an object. It can also be concluded that an attack to the chest would be ideal for maximizing impact force and moving an opponent off balance. Key Points It has been determined that the palm strike is more effective than the punch for developing force and for transferring momentum, most likely the result of a reduced number of rigid links and joints. A strike at head level is less effective than a strike at chest level for developing force and transferring momentum. Distance plays an effect on the overall force and momentum changes, and most likely is dependent on the velocity of the limb and alignment of the bones prior to impact. The teaching of self defence for novices and law enforcement would benefit from including the palm strike as a high priority technique. PMID:24474886
Heel-toe running: A new look at the influence of foot strike pattern on impact force.
Mercer, John A; Horsch, Sarah
2015-06-01
It is important to understand the factors that influence the impact force observed during running, since the impact force is likely to be related to overuse injuries. The purpose of this study was to compare the impact force during running when participants were instructed to use different foot strike patterns: obvious heel strike (Obvious-HS), subtle heel strike (Subtle-HS), midfoot strike (Mid-FS), and fore foot strike (Fore-FS) patterns. Participants ( n = 10, 25 ± 5.7 years, 70.2 ± 12.1 kg, 174.6 ± 7.2 cm) completed four foot strike patterns while running over ground: Obvious-HS, Subtle-HS, Mid-FS, and Fore-FS. Speed was controlled between conditions (random order). Vertical ground reaction forces were recorded (1000 Hz) along with the impact force, peak force, and stance time for analysis. A repeated measures analysis of variance was used to compare each variable across foot strike instructions, with post hoc comparisons contrasting Obvious-HS to each of the other conditions. Impact force was influenced by foot strike instructions, with Obvious-HS being greater than Subtle-HS and Fore-FS ( p < 0.05) but not different from Mid-FS ( p > 0.05). The peak force was not influenced by foot strike instructions ( p > 0.05); stance time was longer during Obvious-HS than during Mid-FS or Fore-FS ( p < 0.05), but not different from Subtle-HS ( p > 0.05). The unique observation of this study was that impact force was different when participants were instructed to run with either an Obvious-HS or a Subtle-HS at contact. Both these foot strike patterns would have been considered rear foot strike patterns, suggesting that something other than which specific part of the foot strikes the ground initially influenced impact force.
Gait Retraining From Rearfoot Strike to Forefoot Strike does not change Running Economy.
Roper, Jenevieve Lynn; Doerfler, Deborah; Kravitz, Len; Dufek, Janet S; Mermier, Christine
2017-12-01
Gait retraining is a method for management of patellofemoral pain, which is a common ailment among recreational runners. The present study investigated the effects of gait retraining from rearfoot strike to forefoot strike on running economy, heart rate, and respiratory exchange ratio immediately post-retraining and one-month post-retraining in recreational runners with patellofemoral pain. Knee pain was also measured. Sixteen participants (n=16) were randomly placed in the control (n=8) or experimental (n=8) group. A 10-minute treadmill RE test was performed by all subjects. The experimental group performed eight gait retraining running sessions where foot strike pattern was switched from rearfoot strike to forefoot strike, while the control group received no intervention. There were no significant differences for running economy (p=0.26), respiratory exchange ratio (p=0.258), or heart rate (p=0.248) between the groups. Knee pain reported on a visual analog scale was also significantly reduced (p<0.05) as a result of retraining. The present study demonstrates that retraining from rearfoot strike to forefoot strike did not affect running economy up to one-month post-retraining while reducing running-related patellofemoral pain. © Georg Thieme Verlag KG Stuttgart · New York.
Effects of Foot Strike and Step Frequency on Achilles Tendon Stress During Running.
Lyght, Michael; Nockerts, Matthew; Kernozek, Thomas W; Ragan, Robert
2016-08-01
Achilles tendon (AT) injuries are common in runners. The AT withstands high magnitudes of stress during running which may contribute to injury. Our purpose was to examine the effects of foot strike pattern and step frequency on AT stress and strain during running utilizing muscle forces based on a musculoskeletal model and subject-specific ultrasound-derived AT cross-sectional area. Nineteen female runners performed running trials under 6 conditions, including rearfoot strike and forefoot strike patterns at their preferred cadence, +5%, and -5% preferred cadence. Rearfoot strike patterns had less peak AT stress (P < .001), strain (P < .001), and strain rate (P < .001) compared with the forefoot strike pattern. A reduction in peak AT stress and strain were exhibited with a +5% preferred step frequency relative to the preferred condition using a rearfoot (P < .001) and forefoot (P=.005) strike pattern. Strain rate was not different (P > .05) between step frequencies within each foot strike condition. Our results suggest that a rearfoot pattern may reduce AT stress, strain, and strain rate. Increases in step frequency of 5% above preferred frequency, regardless of foot strike pattern, may also lower peak AT stress and strain.
Developing personal values: trainees' attitudes toward strikes by health care providers.
Li, Su-Ting T; Srinivasan, Malathi; Der-Martirosian, Claudia; Kravitz, Richard L; Wilkes, Michael S
2011-05-01
Worldwide, health care providers use strikes and job actions to influence policy. For health care providers, especially physicians, strikes create an ethical tension between an obligation to care for current patients (e.g., to provide care and avoid abandonment) and an obligation to better care for future patients by seeking system improvements (e.g., improvements in safety, to access, and in the composition and strength of the health care workforce). This tension is further intensified when the potential benefit of a strike involves professional self-interest and the potential risk involves patient harm or death. By definition, trainees are still forming their professional identities and values, including their opinions on fair wages, health policy, employee benefits, professionalism, and strikes. In this article, the authors explore these ethical tensions, beginning with a discussion of reactions to a potential 2005 nursing strike at the University of California, Davis, Medical Center. The authors then propose a conceptual model describing factors that may influence health care providers' decisions to strike (including personal ethics, personal agency, and strike-related context). In particular, the authors explore the relationship between training level and attitudes toward taking a job action, such as going on strike. Because trainees' attitudes toward strikes continue to evolve during training, the authors maintain that open discussion around the ethics of health care professionals' strikes and other methods of conflict resolution should be included in medical education to enhance professionalism and systems-based practice training. The authors include sample case vignettes to help initiate these important discussions. Copyright © by the Association of American medical Colleges.
Physicians' strikes--a rejoinder.
Glick, S M
1985-01-01
The author, a physician, rejects a previous defence of a doctors' strike. There is little justification for strikes in general, still less for doctors' strikes, he claims. Should not doctors rather 'stand above the common herd' and set an example, he asks. Furthermore the whole idea of strikes in which a third and innocent party is deliberately punished in order to apply pressure on someone else is a 'a bizarre ethic indeed' and not to his knowledge justified under any ethical theory. PMID:4078858
McKeown, Mark H.; Beason, Steven C.
1991-01-01
The radial arm strike rail assembly is a system for measurement of bearings, directions, and stereophotography for geologic mapping, particularly where magnetic compasses are not appropriate. The radial arm, pivoting around a shaft axis, provides a reference direction determination for geologic mapping and bearing or direction determination. The centerable and levelable pedestal provide a base for the radial arm strike rail and the telescoping camera pedestal. The telescoping feature of the radial arm strike rail allows positioning the end of the rail for strike direction or bearing measurement with a goniometer.
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2011-01-14
... exchanges that employ a similar $5 Strike Price Program under their respective rules. Similar reciprocity... securities exchanges. Similar reciprocity currently is permitted with BOX's $1 Strike Program, $.50 Strike... effectiveness of reciprocity provision related to the $5 Strike Price Program). \\15\\ For purposes only of...
Spudich, Paul A.; Chiou, Brian
2015-01-01
We present a two-dimensional system of generalized coordinates for use with geometrically complex fault ruptures that are neither straight nor continuous. The coordinates are a generalization of the conventional strike-normal and strike-parallel coordinates of a single straight fault. The presented conventions and formulations are applicable to a single curved trace, as well as multiple traces representing the rupture of branching faults or noncontiguous faults. An early application of our generalized system is in the second round of the Next Generation of Ground-Motion Attenuation Model project for the Western United States (NGA-West2), where they were used in the characterization of the hanging-wall effects. We further improve the NGA-West2 strike-parallel formulation for multiple rupture traces with a more intuitive definition of the nominal strike direction. We also derive an analytical expression for the gradient of the generalized strike-normal coordinate. The direction of this gradient may be used as the strike-normal direction in the study of polarization effects on ground motions.
Kowalski, Erik; Li, Jing Xian
2016-11-01
This study investigated the normal and parallel ground reaction forces during downhill and uphill running in habitual forefoot strike and habitual rearfoot strike (RFS) runners. Fifteen habitual forefoot strike and 15 habitual RFS recreational male runners ran at 3 m/s ± 5% during level, uphill and downhill overground running on a ramp mounted at 6° and 9°. Results showed that forefoot strike runners had no visible impact peak in all running conditions, while the impact peaks only decreased during the uphill conditions in RFS runners. Active peaks decreased during the downhill conditions in forefoot strike runners while active loading rates increased during downhill conditions in RFS runners. Compared to the level condition, parallel braking peaks were larger during downhill conditions and parallel propulsive peaks were larger during uphill conditions. Combined with previous biomechanics studies, our findings suggest that forefoot strike running may be an effective strategy to reduce impacts, especially during downhill running. These findings may have further implications towards injury management and prevention.
Orthotic intervention in forefoot and rearfoot strike running patterns.
Stackhouse, Carrie Laughton; Davis, Irene McClay; Hamill, Joseph
2004-01-01
To compare the differential effect of custom orthoses on the lower extremity mechanics of a forefoot and rearfoot strike pattern. Fifteen subjects ran with both a forefoot and a rearfoot strike pattern with and without orthoses. Lower extremity kinematic and kinetic variables were compared between strike pattern and orthotic conditions. Foot orthoses have been shown to be effective in controlling excessive rearfoot motion in rearfoot strikers. The effect of orthotic intervention on rearfoot motion in forefoot strikers has not been previously reported. Five trials were collected for each condition. Peak rearfoot eversion, eversion excursion, eversion velocity, peak inversion moment, and inversion work were compared between conditions. Kinematic variables in the sagittal plane of the rearfoot and in the frontal and sagittal plane of the knee were also determined. Increased rearfoot excursions and velocities and decreased peak eversion were noted in the forefoot strike pattern compared to the rearfoot strike pattern. Orthotic intervention, however,did not significantly change rearfoot motion in either strike pattern. Reductions in internal rotation and abduction of the knee were noted with orthotic intervention. Foot orthoses do not differentially effect rearfoot motion of a rearfoot strike and a forefoot strike running pattern. Orthotic intervention has a larger and more systematic effect on rearfoot kinetics compared to rearfoot kinematics.
Variation in Foot Strike Patterns among Habitually Barefoot and Shod Runners in Kenya.
Lieberman, Daniel E; Castillo, Eric R; Otarola-Castillo, Erik; Sang, Meshack K; Sigei, Timothy K; Ojiambo, Robert; Okutoyi, Paul; Pitsiladis, Yannis
2015-01-01
Runners are often categorized as forefoot, midfoot or rearfoot strikers, but how much and why do individuals vary in foot strike patterns when running on level terrain? This study used general linear mixed-effects models to explore both intra- and inter-individual variations in foot strike pattern among 48 Kalenjin-speaking participants from Kenya who varied in age, sex, body mass, height, running history, and habitual use of footwear. High speed video was used to measure lower extremity kinematics at ground contact in the sagittal plane while participants ran down 13 meter-long tracks with three variables independently controlled: speed, track stiffness, and step frequency. 72% of the habitually barefoot and 32% of the habitually shod participants used multiple strike types, with significantly higher levels of foot strike variation among individuals who ran less frequently and who used lower step frequencies. There was no effect of sex, age, height or weight on foot strike angle, but individuals were more likely to midfoot or forefoot strike when they ran on a stiff surface, had a high preferred stride frequency, were habitually barefoot, and had more experience running. It is hypothesized that strike type variation during running, including a more frequent use of forefoot and midfoot strikes, used to be greater before the introduction of cushioned shoes and paved surfaces.
Spencer, McKayka M.; Lardner, Bjorn; Mazurek, M.J.; Reed, Robert N.
2015-01-01
Striking is a typical antipredator defense exhibited by many species of snakes. While trapping Brown Treesnakes (Boiga irregularis) on Guam, we observed that snakes most frequently struck at an approaching person at a site where snakes had been trapped, marked, and handled in the past. Using a combination of between-sites and within-site comparisons, we assessed if the propensity to strike was correlated with capture histories (both recent and long-term), snake size, body condition (a proxy to nutritional stress), sex, or tail condition (broken or intact), while controlling for confounding variables. We confirmed that propensity to strike was higher at the site where we had been conducting capture-mark-recapture for several years. However, we were unable to demonstrate a correlation between striking tendencies and individual recent or long-term capture histories. The only morphological covariate that had an effect on strike propensity was sex, with females striking more often than males. After removing the site effect from our model, we found that snakes missing parts of their tails were more likely to strike than snakes with intact tails. We have yet to identify the factor(s) that cause the pronounced difference across sites in snake propensity to strike, and data from additional sites might help elucidate any geographical patterns.
Martial arts striking hand peak acceleration, accuracy and consistency.
Neto, Osmar Pinto; Marzullo, Ana Carolina De Miranda; Bolander, Richard P; Bir, Cynthia A
2013-01-01
The goal of this paper was to investigate the possible trade-off between peak hand acceleration and accuracy and consistency of hand strikes performed by martial artists of different training experiences. Ten male martial artists with training experience ranging from one to nine years volunteered to participate in the experiment. Each participant performed 12 maximum effort goal-directed strikes. Hand acceleration during the strikes was obtained using a tri-axial accelerometer block. A pressure sensor matrix was used to determine the accuracy and consistency of the strikes. Accuracy was estimated by the radial distance between the centroid of each subject's 12 strikes and the target, whereas consistency was estimated by the square root of the 12 strikes mean squared distance from their centroid. We found that training experience was significantly correlated to hand peak acceleration prior to impact (r(2)=0.456, p =0.032) and accuracy (r(2)=0. 621, p=0.012). These correlations suggest that more experienced participants exhibited higher hand peak accelerations and at the same time were more accurate. Training experience, however, was not correlated to consistency (r(2)=0.085, p=0.413). Overall, our results suggest that martial arts training may lead practitioners to achieve higher striking hand accelerations with better accuracy and no change in striking consistency.
Early care of acute hyperglycemia benefits the outcome of traumatic brain injury in rats.
Kang, Xin; Liu, Yuepeng; Yuan, Tao; Jiang, Na-Na; Dong, Yan-Bin; Wang, Jian-Wei; Fu, Guang-Hui; Liu, Yu-Liang; Wang, Wen-Xue
2016-11-01
Previous animal studies showed contradictory clinical observations on whether acute hyperglycemia contributes to poor outcome in traumatic brain injury (TBI). Herein, we tried to clarify this issue. Striking with depths of 3.0-4.25mm at right occipitoparietal brain region and with depth of 3.75mm at right/left occipitoparietal or right/left frontoparietal brain region were performed, respectively. Blood glucose and insulin levels were traced every four hours from 1 to 72h after striking. HOMA2-%S and HOMA2-%β were calculated. Modified neurological severity scores (mNSS) were used to evaluate neurological deficit within 72h. Striking with depths of 3.5-4.25mm induced increase in blood glucose lasting up to 24h after striking. The levels of blood glucose after striking with depths of 3.75-4.25mm were significantly different from that of striking with the depth of 3.0mm. Striking with depth of 3.75mm at right/left occipitoparietal region induced higher blood glucose in 24h than that at right/left frontoparietal region. Insulin concentration increased slowly during 72h after striking. Striking also induced decrease in insulin sensitivity and secretion lasting 72h. Evaluation of mNSS revealed that severe striking (beyond 3.75mm) worsened nerve function than slight striking (<3.0mm). Intervention of acute hyperglycemia could decrease the mNSS from 2 to 7 days after TBI. Our results suggested that only severe TBI could induce acute hyperglycemia by itself, and early care of acute hyperglycemia could benefit the outcome of TBI patients. Copyright © 2016 Elsevier B.V. All rights reserved.
van der Hoop, Julie M; Vanderlaan, Angelia S M; Taggart, Christopher T
2012-10-01
Vessel strikes are the primary source of known mortality for the endangered North Atlantic right whale (Eubalaena glacialis). Multi-institutional efforts to reduce mortality associated with vessel strikes include vessel-routing amendments such as the International Maritime Organization voluntary "area to be avoided" (ATBA) in the Roseway Basin right whale feeding habitat on the southwestern Scotian Shelf. Though relative probabilities of lethal vessel strikes have been estimated and published, absolute probabilities remain unknown. We used a modeling approach to determine the regional effect of the ATBA, by estimating reductions in the expected number of lethal vessel strikes. This analysis differs from others in that it explicitly includes a spatiotemporal analysis of real-time transits of vessels through a population of simulated, swimming right whales. Combining automatic identification system (AIS) vessel navigation data and an observationally based whale movement model allowed us to determine the spatial and temporal intersection of vessels and whales, from which various probability estimates of lethal vessel strikes are derived. We estimate one lethal vessel strike every 0.775-2.07 years prior to ATBA implementation, consistent with and more constrained than previous estimates of every 2-16 years. Following implementation, a lethal vessel strike is expected every 41 years. When whale abundance is held constant across years, we estimate that voluntary vessel compliance with the ATBA results in an 82% reduction in the per capita rate of lethal strikes; very similar to a previously published estimate of 82% reduction in the relative risk of a lethal vessel strike. The models we developed can inform decision-making and policy design, based on their ability to provide absolute, population-corrected, time-varying estimates of lethal vessel strikes, and they are easily transported to other regions and situations.
ERIC Educational Resources Information Center
Horn, Brian
2017-01-01
This study looks at the experiences of pre-service teachers who began their student teaching assignments amidst the 2012 Chicago Teachers Union strike. Four yearlong student teachers reflected on their understandings of teaching, unionism, and activism before, during, and after the strike. Findings suggest pre-service teachers need greater…
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2011-02-01
... strike prices and non-parallel strikes in different expiration months of the same issue. The Commission... Listing of Options Series With $1 Strike Prices January 25, 2011. I. Introduction On November 24, 2010... Strike Price Program. The proposed rule change was published for comment in the Federal Register on...
A model of high-rate indentation of a cylindrical striking pin into a deformable body
NASA Astrophysics Data System (ADS)
Zalazinskaya, E. A.; Zalazinsky, A. G.
2017-12-01
Mathematical modeling of an impact and high-rate indentation to a significant depth of a flat-faced hard cylindrical striking pin into a massive deformable target body is carried out. With the application of the kinematic extreme theorem of the plasticity theory and the kinetic energy variation theorem, the phase trajectories of the striking pin are calculated, the initial velocity of the striking pin in the body, the limit values of the inlet duct length, and the depth of striking pin penetration into the target are determined.
Manipulation of Foot Strike and Footwear Increases Achilles Tendon Loading During Running.
Rice, Hannah; Patel, Mubarak
2017-08-01
The Achilles tendon is the most common site of tendon overuse injury in humans. Running with a forefoot strike pattern and in minimal shoes is a topic of recent interest, yet evidence is currently limited regarding the combined influence of foot strike and footwear on Achilles tendon loading. To investigate the influence of both foot strike and footwear on Achilles tendon loading in habitual rearfoot strike runners. Controlled laboratory study. Synchronized kinematic and force data were collected from 22 habitual rearfoot strikers (11 male), who habitually ran in nonminimal running shoes, during overground running at 3.6 m·s -1 . Participants ran in 3 different footwear conditions (standard running shoe, minimal running shoe, and barefoot) with both a rearfoot strike (RFS) and an imposed forefoot strike (FFS) in each footwear condition. Achilles tendon loading was estimated by use of inverse dynamics, where the Achilles tendon moment arm was determined with a regression equation. A 2-way, repeated-measures analysis of variance was used to compare conditions. Achilles tendon impulse was greater when subjects ran with an FFS rather than an RFS in minimal shoes. Achilles tendon loading rates were higher when subjects ran either in minimal shoes or barefoot than in standard shoes, regardless of foot strike. In runners who habitually rearfoot strike in standard running shoes, running in minimal shoes or barefoot increased the rate of tendon loading, and running with a forefoot strike in minimal shoes increased the magnitude of tendon loading. Transitioning to these running conditions may increase the risk of tendinopathy.
Variation in Foot Strike Patterns among Habitually Barefoot and Shod Runners in Kenya
Lieberman, Daniel E.; Castillo, Eric R.; Otarola-Castillo, Erik; Sang, Meshack K.; Sigei, Timothy K.; Ojiambo, Robert; Okutoyi, Paul; Pitsiladis, Yannis
2015-01-01
Runners are often categorized as forefoot, midfoot or rearfoot strikers, but how much and why do individuals vary in foot strike patterns when running on level terrain? This study used general linear mixed-effects models to explore both intra- and inter-individual variations in foot strike pattern among 48 Kalenjin-speaking participants from Kenya who varied in age, sex, body mass, height, running history, and habitual use of footwear. High speed video was used to measure lower extremity kinematics at ground contact in the sagittal plane while participants ran down 13 meter-long tracks with three variables independently controlled: speed, track stiffness, and step frequency. 72% of the habitually barefoot and 32% of the habitually shod participants used multiple strike types, with significantly higher levels of foot strike variation among individuals who ran less frequently and who used lower step frequencies. There was no effect of sex, age, height or weight on foot strike angle, but individuals were more likely to midfoot or forefoot strike when they ran on a stiff surface, had a high preferred stride frequency, were habitually barefoot, and had more experience running. It is hypothesized that strike type variation during running, including a more frequent use of forefoot and midfoot strikes, used to be greater before the introduction of cushioned shoes and paved surfaces. PMID:26154285
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2010-06-23
... PHLX, Inc. To List Options on Trust Issued Receipts in $1 Strike Intervals June 15, 2010. Pursuant to... to list options on Trust Issued Receipts in $1 strike price intervals. The text of the proposed rule...)(iv) to Rule 1012, in $1 or greater strike price intervals, where the strike price is $200 or less and...
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2013-11-19
...-money strikes. Elimination of the cap would remedy this issue. Currently, the Exchange lists quarterly... additional strikes. Consequently, the Exchange is not able to list important at-the-money strikes due to the... so that it may list strikes that are closer to the money, delisting is not always possible. If all of...
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... Commission has recently approved certain products to trade at $0.50 and $1 strike price intervals on CBOE... Series (``STOS'') Program that normally trade in $1 Strike Price Intervals shall be $0.50 or greater; and for classes in the STOS Program that do not normally trade in $1 Strike Price Intervals, the strike...
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Yong, Jennifer R; Silder, Amy; Montgomery, Kate L; Fredericson, Michael; Delp, Scott L
2018-05-18
Tibial stress fractures are a common and debilitating injury that occur in distance runners. Runners may be able to decrease tibial stress fracture risk by adopting a running pattern that reduces biomechanical parameters associated with a history of tibial stress fracture. The purpose of this study was to test the hypothesis that converting to a forefoot striking pattern or increasing cadence without focusing on changing foot strike type would reduce injury risk parameters in recreational runners. Running kinematics, ground reaction forces and tibial accelerations were recorded from seventeen healthy, habitual rearfoot striking runners while running in their natural running pattern and after two acute retraining conditions: (1) converting to forefoot striking without focusing on cadence and (2) increasing cadence without focusing on foot strike. We found that converting to forefoot striking decreased two risk factors for tibial stress fracture: average and peak loading rates. Increasing cadence decreased one risk factor: peak hip adduction angle. Our results demonstrate that acute adaptation to forefoot striking reduces different injury risk parameters than acute adaptation to increased cadence and suggest that both modifications may reduce the risk of tibial stress fractures. Copyright © 2018 Elsevier Ltd. All rights reserved.
Modern Protection Against Lightning Strikes
NASA Astrophysics Data System (ADS)
Moore, C.
2005-05-01
The application of science to provide protection against lightning strikes began around 1750 when Benjamin Franklin who invented the lightning rod in an effort to discharge thunderclouds. Instead of preventing lightning as he expected, his rods have been quite successful as strike receptors, intercepting cloud-to ground discharges and conducting them to Earth without damage to the structures on which they are mounted. In the years since Franklin's invention there has been little attention paid to the rod configuration that best serves as a strike receptor but Franklin's original ideas continue to be rediscovered and promoted. Recent measurements of the responses of variously configured rods to nearby strikes indicate that sharp-tipped rods are not the optimum configuration to serve as strike receptors since the ionization of the air around their tips limits the strength of the local electric fields created by an approaching lightning leader. In these experiments, fourteen blunt-tipped rods exposed in strike-reception competitions with nearby sharp-tipped rods were struck by lightning but none of the sharp-tipped rods were struck.
Expertise of using striking techniques for power stroke in badminton.
Zhu, Qin
2013-10-01
Two striking techniques (fast swing and angled striking) were examined to see if they allowed effective use of string tension for the power stroke in badminton. 12 participants (4 novices, 4 recreational, and 4 expert badminton players) were recorded by a fast-speed camera while striking a shuttlecock with racquets of 8 different string tensions. The peak speed of the shuttlecock, the racquet angle and the shuttlecock angle were analyzed. The results showed that expert players succeeded in using both striking techniques to overcome the constraint of string tension and produce a consistently superior stroke. Failure to use either striking technique resulted in inferior performance that was constrained by string tension. Expertise in badminton allows the necessary motor adjustments based on the affordance perception of the string tension.
Head Trauma in Mixed Martial Arts.
Hutchison, Michael G; Lawrence, David W; Cusimano, Michael D; Schweizer, Tom A
2014-06-01
Mixed martial arts (MMA) is a full combative sport with a recent global increase in popularity despite significant scrutiny from medical associations. To date, the empirical research of the risk of head injuries associated with this sport is limited. Youth and amateur participation is growing, warranting investigation into the burden and mechanism of injuries associated with this sport. (1) To determine the incidence, risk factors, and characteristics of knockouts (KOs) and technical knockouts (TKOs) from repetitive strikes in professional MMA; and (2) to identify the mechanisms of head trauma and the situational factors that lead to KOs and TKOs secondary to repetitive strikes through video analysis. Descriptive epidemiology study. Competition data and video records for all KOs and TKOs from numbered Ultimate Fighting Championship MMA events (n = 844) between 2006 to 2012. Analyses included (1) multivariate logistic regression to investigate factors associated with an increased risk of sustaining a KO or TKO secondary to repetitive strikes and (2) video analysis of all KOs and TKOs secondary to repetitive strikes with descriptive statistics. During the study period, the KO rate was 6.4 per 100 athlete-exposures (AEs) (12.7% of matches), and the rate of TKOs secondary to repetitive strikes was 9.5 per 100 AEs (19.1% of matches), for a combined incidence of match-ending head trauma of 15.9 per 100 AEs (31.9% of matches). Logistic regression identified that weight class, earlier time in a round, earlier round in a match, and older age were risk factors for both KOs and TKOs secondary to repetitive strikes. Match significance and previously sustained KOs or TKOs were also risk factors for KOs. Video analysis identified that all KOs were the result of direct impact to the head, most frequently a strike to the mandibular region (53.9%). The average time between the KO-strike and match stoppage was 3.5 seconds (range, 0-20 seconds), with losers sustaining an average of 2.6 additional strikes (range, 0-20 strikes) to the head. For TKOs secondary to strikes, in the 30-second interval immediately preceding match stoppage, losers sustained, on average, 18.5 strikes (range, 5-46 strikes), with 92.3% of these being strikes to the head. Rates of KOs and TKOs in MMA are higher than previously reported rates in other combative and contact sports. Public health authorities and physicians should be cognizant of the rates and mechanisms of head trauma. Preventive measures to lessen the risks of head trauma for those who elect to participate in MMA are described. © 2014 The Author(s).
2013-01-01
Background Doctor and healthcare worker (HCW) strikes are a global phenomenon with the potential to negatively impact on the quality of healthcare services and the doctor-patient relationship. Strikes are a legitimate deadlock breaking mechanism employed when labour negotiations have reached an impasse during collective bargaining. Striking doctors usually have a moral dilemma between adherence to the Hippocratic tenets of the medical profession and fiduciary obligation to patients. In such circumstances the ethical principles of respect for autonomy, justice and beneficence all come into conflict, whereby doctors struggle with their role as ordinary employees who are rightfully entitled to a just wage for just work versus their moral obligations to patients and society. Discussion It has been argued that to deny any group of workers, including "essential workers" the right to strike is akin to enslavement which is ethically and morally indefensible. While HCW strikes occur globally, the impact appears more severe in developing countries challenged by poorer socio-economic circumstances, embedded infrastructural deficiencies, and lack of viable alternative means of obtaining healthcare. These communities appear to satisfy the criteria for vulnerability and may be deserving of special ethical consideration when doctor and HCW strikes are contemplated. Summary The right to strike is considered a fundamental right whose derogation would be inimical to the proper functioning of employer/employee collective bargaining in democratic societies. Motivations for HCW strikes include the natural pressure to fulfil human needs and the paradigm shift in modern medical practice, from self-employment and benevolent paternalism, to managed healthcare and consumer rights. Minimizing the incidence and impact of HCW strikes will require an ethical approach from all stakeholders, and recognition that all parties have an equal moral obligation to serve the best interests of society. Employers should implement legitimate collective bargaining agreements in a timely manner and high-handed actions such as mass-firing of striking HCWs, or unjustifiable disciplinary action by regulators should be avoided. Minimum service level agreements should be implemented to mitigate the impact of HCW strikes on indigent populations. Striking employees including HCWs should also desist from making unrealistic wage demands which could bankrupt governments/employers or hamper provision of other equally important social services to the general population. PMID:24564968
ERIC Educational Resources Information Center
National Alliance of Business, Inc., Washington, DC.
CertainTeed's Precision Strike training program was designed to close the gaps between the current status of its workplace and where that work force needed to be to compete successfully in global markets. Precision Strike included Skills and Knowledge in Lifelong Learning (SKILL) customized, computerized lessons in basic skills, one-on-one…
ERIC Educational Resources Information Center
Igoe, Joseph A.; DiRocco, Anthony P.
This booklet is designed to give practical and realistic advice to school district officials faced with the possibility of a teachers' strike. It is intended for use both by school district administrators and school board members. The booklet is organized into four sections that focus in turn on signs of a pending teachers' strike, union…
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-06
... Amend the BOX Rules To Expand the $2.50 Strike Price Program March 31, 2011. Pursuant to Section 19(b)(1..., LLC (``BOX'') to expand the $2.50 Strike Price Program. The text of the proposed rule change is... Strike Price Program (``Program'') \\4\\ to permit the listing of options with $2.50 strike price intervals...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-11-03
... strike, an out-of-the-money option. However, if a $0.50 strike series had been available, the investor would have been able to control 5,000 shares by purchasing 50 exercisable in-the-money $0.50 strike call... the time was $1, an in-the-money option. If a $0.50 strike series had been available, the investor...
2005 Precision Strike Annual Programs Review
2005-04-20
Control Canards (4) Polyurethane Foam Support DPICM (404 M101 Grenades) Warhead Fuze: Electronic Safe & Arm Device (ESAD) UNCLASSIFIED UNCLASSIFIED PF...SYSTEMS: • JASSM: Colonel James Geurts, USAF JASSM PM • ATACMS : Colonel Earnest Harris, USA PM, Precision Fires Rockets & Missiles, PEO Space and...UNCLASSIFIED UNCLASSIFIED Viper Strike Lineage ATACMS Delivered Base BATs Viper Strike SAL Seeker Proof of Principle Demos I & II Hunter-Viper Strike
Goss, Donald L; Lewek, Michael; Yu, Bing; Ware, William B; Teyhen, Deydre S; Gross, Michael T
2015-06-01
The injury incidence rate among runners is approximately 50%. Some individuals have advocated using an anterior-foot-strike pattern to reduce ground reaction forces and injury rates that they attribute to a rear-foot-strike pattern. The proportion of minimalist shoe wearers who adopt an anterior-foot-strike pattern remains unclear. To evaluate the accuracy of self-reported foot-strike patterns, compare negative ankle- and knee-joint angular work among runners using different foot-strike patterns and wearing traditional or minimalist shoes, and describe average vertical-loading rates. Descriptive laboratory study. Research laboratory. A total of 60 healthy volunteers (37 men, 23 women; age = 34.9 ± 8.9 years, height = 1.74 ± 0.08 m, mass = 70.9 ± 13.4 kg) with more than 6 months of experience wearing traditional or minimalist shoes were instructed to classify their foot-strike patterns. Participants ran in their preferred shoes on an instrumented treadmill with 3-dimensional motion capture. Self-reported foot-strike patterns were compared with 2-dimensional video assessments. Runners were classified into 3 groups based on video assessment: traditional-shoe rear-foot strikers (TSR; n = 22), minimalist-shoe anterior-foot strikers (MSA; n = 21), and minimalist-shoe rear-foot strikers (MSR; n = 17). Ankle and knee negative angular work and average vertical-loading rates during stance phase were compared among groups. Only 41 (68.3%) runners reported foot-strike patterns that agreed with the video assessment (κ = 0.42, P < .001). The TSR runners demonstrated greater ankle-dorsiflexion and knee-extension negative work than MSA and MSR runners (P < .05). The MSA (P < .001) and MSR (P = .01) runners demonstrated greater ankle plantar-flexion negative work than TSR runners. The MSR runners demonstrated a greater average vertical-loading rate than MSA and TSR runners (P < .001). Runners often cannot report their foot-strike patterns accurately and may not automatically adopt an anterior-foot-strike pattern after transitioning to minimalist running shoes.
Variation in Foot Strike Patterns during Running among Habitually Barefoot Populations
Hatala, Kevin G.; Dingwall, Heather L.; Wunderlich, Roshna E.; Richmond, Brian G.
2013-01-01
Endurance running may have a long evolutionary history in the hominin clade but it was not until very recently that humans ran wearing shoes. Research on modern habitually unshod runners has suggested that they utilize a different biomechanical strategy than runners who wear shoes, namely that barefoot runners typically use a forefoot strike in order to avoid generating the high impact forces that would be experienced if they were to strike the ground with their heels first. This finding suggests that our habitually unshod ancestors may have run in a similar way. However, this research was conducted on a single population and we know little about variation in running form among habitually barefoot people, including the effects of running speed, which has been shown to affect strike patterns in shod runners. Here, we present the results of our investigation into the selection of running foot strike patterns among another modern habitually unshod group, the Daasanach of northern Kenya. Data were collected from 38 consenting adults as they ran along a trackway with a plantar pressure pad placed midway along its length. Subjects ran at self-selected endurance running and sprinting speeds. Our data support the hypothesis that a forefoot strike reduces the magnitude of impact loading, but the majority of subjects instead used a rearfoot strike at endurance running speeds. Their percentages of midfoot and forefoot strikes increased significantly with speed. These results indicate that not all habitually barefoot people prefer running with a forefoot strike, and suggest that other factors such as running speed, training level, substrate mechanical properties, running distance, and running frequency, influence the selection of foot strike patterns. PMID:23326341
Foot strike patterns after obstacle clearance during running.
Scholten, Shane D; Stergiou, Nicholas; Hreljac, Alan; Houser, Jeremy; Blanke, Daniel; Alberts, L Russell
2002-01-01
Running over obstacles of sufficient height requires heel strike (HS) runners to make a transition in landing strategy to a forefoot (FF) strike, resulting in similar ground reaction force patterns to those observed while landing from a jump. Identification of the biomechanical variables that distinguish between the landing strategies may offer some insight into the reasons that the transition occurs. The purpose of this study was to investigate the difference in foot strike patterns and kinetic parameters of heel strike runners between level running and running over obstacles of various heights. Ten heel strike subjects ran at their self-selected pace under seven different conditions: unperturbed running (no obstacle) and over obstacles of six different heights (10%, 12.5%, 15%, 17.5%, 20%, and 22.5% of their standing height). The obstacle was placed directly before a Kistler force platform. Repeated measures ANOVAs were performed on the subject means of selected kinetic parameters. The statistical analysis revealed significant differences (P < 0.004) for all of the parameters analyzed. The evaluation of the center of pressure and the ground reaction forces indicated that the foot strike patterns were affected by the increased obstacle height. Between the 12.5% and 15% obstacle conditions, the group response changed from a heel strike to a forefoot strike pattern. At height > 15%, the pattern was more closely related to the foot strike patterns found in jumping activities. This strategy change may represent a gait transition effected as a mechanism to protect against increased impact forces. Greater involvement of the ankle and the calf muscles could have assisted in attenuating the increased impact forces while maintaining speed after clearing the obstacle.
Variation in foot strike patterns during running among habitually barefoot populations.
Hatala, Kevin G; Dingwall, Heather L; Wunderlich, Roshna E; Richmond, Brian G
2013-01-01
Endurance running may have a long evolutionary history in the hominin clade but it was not until very recently that humans ran wearing shoes. Research on modern habitually unshod runners has suggested that they utilize a different biomechanical strategy than runners who wear shoes, namely that barefoot runners typically use a forefoot strike in order to avoid generating the high impact forces that would be experienced if they were to strike the ground with their heels first. This finding suggests that our habitually unshod ancestors may have run in a similar way. However, this research was conducted on a single population and we know little about variation in running form among habitually barefoot people, including the effects of running speed, which has been shown to affect strike patterns in shod runners. Here, we present the results of our investigation into the selection of running foot strike patterns among another modern habitually unshod group, the Daasanach of northern Kenya. Data were collected from 38 consenting adults as they ran along a trackway with a plantar pressure pad placed midway along its length. Subjects ran at self-selected endurance running and sprinting speeds. Our data support the hypothesis that a forefoot strike reduces the magnitude of impact loading, but the majority of subjects instead used a rearfoot strike at endurance running speeds. Their percentages of midfoot and forefoot strikes increased significantly with speed. These results indicate that not all habitually barefoot people prefer running with a forefoot strike, and suggest that other factors such as running speed, training level, substrate mechanical properties, running distance, and running frequency, influence the selection of foot strike patterns.
NASA Technical Reports Server (NTRS)
Burns, Lee; Decker, Ryan
2005-01-01
Lightning strike location and peak current are monitored operationally in the Kennedy Space Center (KSC) Cape Canaveral Air Force Station (CCAFS) area by the Cloud to Ground Lightning Surveillance System (CGLSS). The present study compiles ten years worth of CGLSS data into a database of near strikes. Using shuffle launch platform LP39A as a convenient central point, all strikes recorded within a 20-mile radius for the period of record O R ) from January 1, 1993 to December 31,2002 were included in the subset database. Histograms and cumulative probability curves are produced for both strike intensity (peak current, in kA) and the corresponding magnetic inductance fields (in A/m). Results for the full POR have application to launch operations lightning monitoring and post-strike test procedures.
Power electromagnetic strike machine for engineering-geological surveys
NASA Astrophysics Data System (ADS)
Usanov, K. M.; Volgin, A. V.; Chetverikov, E. A.; Kargin, V. A.; Moiseev, A. P.; Ivanova, Z. I.
2017-10-01
When implementing the processes of dynamic sensing of soils and pulsed nonexplosive seismic exploration, the most common and effective method is the strike one, which is provided by a variety of structure and parameters of pneumatic, hydraulic, electrical machines of strike action. The creation of compact portable strike machines which do not require transportation and use of mechanized means is important. A promising direction in the development of strike machines is the use of pulsed electromagnetic actuator characterized by relatively low energy consumption, relatively high specific performance and efficiency, and providing direct conversion of electrical energy into mechanical work of strike mass with linear movement trajectory. The results of these studies allowed establishing on the basis of linear electromagnetic motors the electromagnetic pulse machines with portable performance for dynamic sensing of soils and land seismic pulse of small depths.
An Inverse Kinematic Approach Using Groebner Basis Theory Applied to Gait Cycle Analysis
2013-03-01
stance phase begins with initial contact, heel strike , and ends with toe off. The swing phase begins at toe off and ends with the heel striking the ground...and transition phase (10%). Recall, that the gait cycle begins when the heel strikes the ground of one foot and ends when that same foot strikes the...Validation of Knee Angle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 12 Validation of Ankle Angle
Bowersock, Collin D; Willy, Richard W; DeVita, Paul; Willson, John D
2017-10-01
The purpose of this study was to examine the effects of step length and foot strike pattern along with their interaction on tibiofemoral joint (TFJ) and medial compartment TFJ kinetics during running. Nineteen participants ran with a rear foot strike pattern at their preferred speed using a short (-10%), preferred, and long (+10%) step length. These step length conditions were then repeated using a forefoot strike pattern. Regardless of foot strike pattern, a 10% shorter step length resulted in decreased peak contact force, force impulse per step, force impulse per kilometre, and average loading rate at the TFJ and medial compartment, while a 10% increased step length had the opposite effects (all P < 0.05). A forefoot strike pattern significantly lowered TFJ and medial compartment TFJ average loading rates compared with a rear foot strike pattern (both <0.05) but did not change TFJ or medial compartment peak force, force impulse per step, or force impulse per km. The combination of a shorter step length and forefoot strike pattern produced the greatest reduction in peak medial compartment contact force (P < 0.05). Knowledge of these running modification effects may be relevant to the management or prevention of TFJ injury or pathology among runners.
Conventional Prompt Global Strike and Long-Range Ballistic Missiles: Background and Issues
2012-07-06
Missiles Congressional Research Service Forward-Based Global Strike ( FBGS ...Congressional Research Service 36 Forward-Based Global Strike ( FBGS ) Analysts have also explored the option of deploying long-range land-based
de Almeida, Matheus Oliveira; Saragiotto, Bruno Tirotti; Yamato, Tiê Parma; Lopes, Alexandre Dias
2015-02-01
To determine the distribution of the foot strike patterns among recreational shod runners and to compare the personal and training characteristics between runners with different foot strike patterns. Cross-sectional study. Areas of running practice in São Paulo, Brazil. 514 recreational shod runners older than 18 years and free of injury. Foot strike patterns were evaluated with a high-speed camera (250 Hz) and photocells to assess the running speed of participants. Personal and training characteristics were collected through a questionnaire. The inter-rater reliability of the visual foot strike pattern classification method was 96.7% and intra-rater reliability was 98.9%. 95.1% (n = 489) of the participants were rearfoot strikers, 4.1% (n = 21) were midfoot strikers, and four runners (0.8%) were forefoot strikers. There were no significant differences between strike patterns for personal and training characteristics. This is the first study to demonstrate that almost all recreational shod runners were rearfoot strikers. The visual method of evaluation seems to be a reliable and feasible option to classify foot strike pattern. Copyright © 2014 Elsevier Ltd. All rights reserved.
Launch pad lightning protection effectiveness
NASA Technical Reports Server (NTRS)
Stahmann, James R.
1991-01-01
Using the striking distance theory that lightning leaders will strike the nearest grounded point on their last jump to earth corresponding to the striking distance, the probability of striking a point on a structure in the presence of other points can be estimated. The lightning strokes are divided into deciles having an average peak current and striking distance. The striking distances are used as radii from the points to generate windows of approach through which the leader must pass to reach a designated point. The projections of the windows on a horizontal plane as they are rotated through all possible angles of approach define an area that can be multiplied by the decile stroke density to arrive at the probability of strokes with the window average striking distance. The sum of all decile probabilities gives the cumulative probability for all strokes. The techniques can be applied to NASA-Kennedy launch pad structures to estimate the lightning protection effectiveness for the crane, gaseous oxygen vent arm, and other points. Streamers from sharp points on the structure provide protection for surfaces having large radii of curvature. The effects of nearby structures can also be estimated.
NASA Astrophysics Data System (ADS)
Sakran, Shawky; Said, Said Mohamed
2018-02-01
Detailed surface geological mapping and subsurface seismic interpretation have been integrated to unravel the structural style and kinematic history of the Nubian Fault System (NFS). The NFS consists of several E-W Principal Deformation Zones (PDZs) (e.g. Kalabsha fault). Each PDZ is defined by spectacular E-W, WNW and ENE dextral strike-slip faults, NNE sinistral strike-slip faults, NE to ENE folds, and NNW normal faults. Each fault zone has typical self-similar strike-slip architecture comprising multi-scale fault segments. Several multi-scale uplifts and basins were developed at the step-over zones between parallel strike-slip fault segments as a result of local extension or contraction. The NNE faults consist of right-stepping sinistral strike-slip fault segments (e.g. Sin El Kiddab fault). The NNE sinistral faults extend for long distances ranging from 30 to 100 kms and cut one or two E-W PDZs. Two nearly perpendicular strike-slip tectonic regimes are recognized in the NFS; an inactive E-W Late Cretaceous - Early Cenozoic dextral transpression and an active NNE sinistral shear.
Conventional Prompt Global Strike and Long-Range Ballistic Missiles: Background and Issues
2012-02-13
Ballistic Missiles Congressional Research Service Forward-Based Global Strike ( FBGS ...missiles in the CPGS program. Forward-Based Global Strike ( FBGS ) Analysts have also explored the option of deploying long-range land-based ballistic
The 1983 direct strike lightning data, part 1
NASA Technical Reports Server (NTRS)
Thomas, Mitchel E.
1985-01-01
Data waveforms are presented which were obtained during the 1983 direct strike lightning tests utilizing the NASA F106-B aircraft specially instrumented for lightning electromagnetic measurements. The aircraft was operated in the vicinity of the NASA Langley Research Center, Hampton, Virginia, in a thunderstorm environment to elicit strikes. Electromagnetic field data and conduction currents on the aircraft were recorded for attached lightning. Part 1 contains 435 pages of lightning strike data in chart form.
The 1983 direct strike lightning data, part 2
NASA Technical Reports Server (NTRS)
Thomas, Mitchel E.
1985-01-01
Data waveforms are presented which were obtained during the 1983 direct strike lightning tests utilizing the NASA F106-B aircraft specially instrumented for lightning electromagnetic measurements. The aircraft was operated in the vicinity of the NASA Langley Research Center, Hampton, Virginia, in a thunderstorm environment to elicit strikes. Electromagnetic field data and conduction currents on the aircraft were recorded for attached lightning. Part 2 contains 443 pages of lightning strike data in chart form.
Strike action electromagnetic machine for immersion of rod elements into ground
NASA Astrophysics Data System (ADS)
Usanov, K. M.; Volgin, A. V.; Chetverikov, E. A.; Kargin, V. A.; Moiseev, A. P.; Ivanova, Z. I.
2017-10-01
During construction, survey work, and drilling shallow wells by striking, operations associated with dipping and removing the rod elements are the most common. At the same time relatively long, with small diameter, elements, in which the ratio of length to diameter l/d is 100 or more, constitute a significant proportion. At present, the application of power pulse linear electromagnetic motors to drive drum machines is recognized to be highly effective. However, the mechanical method of transmission of shocks does not allow dipping long longitudinally unstable core elements. In this case, mechanical energy must be transferred from the motor to the rod through its side surface. The design of the strike action electromagnetic machine with a through axial channel for non-mechanical end striking of the pile of long, longitudinally unstable metal rods is proposed. Electromagnetic striking machine for non-mechanical end striking rod elements provides operations characterized by ecological compatibility, safety and high quality.
Strike kinematics and performance in juvenile ball pythons (Python regius).
Ryerson, William G; Tan, Weimin
2017-08-01
The rapid strike of snakes has interested researchers for decades. Although most work has focused on the strike performance of vipers, recent work has shown that other snakes outside of the Viperidae can strike with the same velocities and accelerations. However, to date all of these examples focus on performance in adult snakes. Here, we use high-speed video to measure the strike kinematics and performance of 10 juvenile (<6 months of age) ball pythons, Python regius. We find that juvenile P. regius strike at levels comparable to larger snakes, but with shorter durations and over shorter distances. We conclude that the juvenile P. regius maintain performance likely through manipulation of the axial musculature and accompanying elastic tissues, and that this is a first step to understanding ontogenetic changes in behavior and a potential avenue for understanding how captivity may also impact behavior. © 2017 Wiley Periodicals, Inc.
The origin of strike-slip tectonics in continental rifts
NASA Astrophysics Data System (ADS)
Ebinger, C. J.; Pagli, C.; Yun, S. H.; Keir, D.; Wang, H.
2016-12-01
Although continental rifts are zones of lithospheric extension, strike-slip tectonics is also accommodated within rifts and its origin remains controversial. Here we present a combined analysis of recent seismicity, InSAR and GPS derived strain maps to reveal that the plate motion in Afar is accommodated primarily by extensional tectonics in all rift arms and lacks evidences of regional scale bookshelf tectonics. However in the rifts of central Afar we identify crustal extension and normal faulting in the central part of the rifts but strike-slip earthquakes at the rift tips. We investigate if strike-slip can be the result of Coulomb stress changes induced by recent dyking but models do not explain these earthquakes. Instead we explain strike-slips as shearing at the tips of a broad zone of spreading where extension terminates against unstretched lithosphere. Our results demonstrate that plate spreading can develop both strike-slip and extensional tectonics in the same rifts.
Risk Considerations of Bird Strikes to Space Launch Vehicles
NASA Technical Reports Server (NTRS)
Hales, Christy; Ring, Robert
2016-01-01
Within seconds after liftoff of the Space Shuttle during mission STS-114, a turkey vulture impacted the vehicle's external tank. The contact caused no apparent damage to the Shuttle, but the incident led NASA to consider the potential consequences of bird strikes during a Shuttle launch. The environment at Kennedy Space Center provides unique bird strike challenges due to the Merritt Island National Wildlife Refuge and the Atlantic Flyway bird migration routes. NASA is currently refining risk assessment estimates for the probability of bird strike to space launch vehicles. This paper presents an approach for analyzing the risks of bird strikes to space launch vehicles and presents an example. The migration routes, types of birds present, altitudes of those birds, exposed area of the launch vehicle, and its capability to withstand impacts affect the risk due to bird strike. A summary of significant risk contributors is discussed.
Thunderstorm hazards flight research: Storm hazards 1980 overview
NASA Technical Reports Server (NTRS)
Deal, P. L.; Keyser, G. L.; Fisher, B. D.; Crabill, N. L.
1981-01-01
A highly instrumented NASA F-106B aircraft, modified for the storm hazards mission and protected against direct lightning strikes, was used in conjunction with various ground based radar and lightning measurement systems to collect data during thunderstorm penetration flights. During 69 thunderstorm penetrations, there were 10 direct lightning strikes to the aircraft. No problems were encountered with any of the aircraft's systems as a result of the strikes and the research instrumentation performed as designed. Electromagnetic characteristics of nine strikes were recorded, and the results of other experiments confirm the theory that X-ray radiation and nitrous oxide gas are being produced by processes associated directly with thunderstorm electric fields and lightning discharges. A better understanding of aircraft lightning attachment mechanisms and strike zones is being accomplished by careful inspection, identification, and documentation of lightning attachment points and swept stroke paths following each strike to the aircraft.
Turner, Rachel; Arsevska, Elena; Brant, Beth; Singleton, David A; Newman, Jenny; Noble, Pj-M; Jones, Philip H; Radford, Alan D
2018-05-01
Blowfly strike is a devastating and often rapidly fatal disease in rabbits. In Great Britain (GB), Lucilia sericata is the primary causative species. Despite its severity, there has been minimal investigatory work into the disease in rabbits. Here we used text mining to screen electronic health records (EHRs) from a large sentinel network of 389 veterinary practices in GB between March 2014 and April 2017 for confirmed cases of blowfly strike in rabbits. Blowfly strike was identified in 243 of 42,226 rabbit consultations (0.6%), affecting 205 individual rabbits. The anatomical site of recorded blowfly strike lesions was overwhelmingly the perineal area (n = 109, 52.4%). Less commonly lesions were observed affecting other areas of the body (n = 9, 4.3%) and head (n = 8, 3.8%); in 83 consultations (39.9%), the affected area was not specified. Of the rabbits presenting with blowfly strike, 44.7% were recorded as being euthanized or died. A case control study was used to identify risk factors for blowfly strike in this population. Whilst sex and neuter status in isolation were not significantly associated with blowfly strike, entire female rabbits showed a 3.3 times greater odds of being a case than neutered female rabbits. Rabbits five years of age and over were more than 3.8 times likely to present for blowfly strike. For every 1 °C rise in environmental temperature between 4.67 °C and 17.68 °C, there was a 33% increase risk of blowfly strike, with cases peaking in July or August. Overall blowfly strike cases started earlier and peaked higher in the south of Great Britain. The most northerly latitude studied was at lower risk of blowfly strike than the most southerly (OR = 0.50, p < 0.001). There appeared to be no significant relationship between blowfly strike in rabbits and either the sheep density or rural and urban land coverage types. The results presented here can be used for targeted health messaging to reduce the impact of this deadly disease for rabbits. We propose that real-time temporal and spatial surveillance of the rabbit disease may also help inform sheep control, where the seasonal profile is very similar, and where routine surveillance data is also not available. Our results highlight the value of sentinel databases based on EHRs for research and surveillance. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.
McGill, Stuart M; Chaimberg, Jon D; Frost, David M; Fenwick, Chad M J
2010-02-01
The main issue addressed here is the paradox of muscle contraction to optimize speed and strike force. When muscle contracts, it increases in both force and stiffness. Force creates faster movement, but the corresponding stiffness slows the change of muscle shape and joint velocity. The purpose of this study was to investigate how this speed strength is accomplished. Five elite mixed martial arts athletes were recruited given that they must create high strike force very quickly. Muscle activation using electromyography and 3-dimensional spine motion was measured. A variety of strikes were performed. Many of the strikes intend to create fast motion and finish with a very large striking force, demonstrating a "double peak" of muscle activity. An initial peak was timed with the initiation of motion presumably to enhance stiffness and stability through the body before motion. This appeared to create an inertial mass in the large "core" for limb muscles to "pry" against to initiate limb motion. Then, some muscles underwent a relaxation phase as speed of limb motion increased. A second peak was observed upon contact with the opponent (heavy bag). It was postulated that this would increase stiffness through the body linkage, resulting in a higher effective mass behind the strike and likely a higher strike force. Observation of the contract-relax-contract pulsing cycle during forceful and quick strikes suggests that it may be fruitful to consider pulse training that involves not only the rate of muscle contraction but also the rate of muscle relaxation.
Osis, Sean T; Hettinga, Blayne A; Leitch, Jessica; Ferber, Reed
2014-08-22
As 3-dimensional (3D) motion-capture for clinical gait analysis continues to evolve, new methods must be developed to improve the detection of gait cycle events based on kinematic data. Recently, the application of principal component analysis (PCA) to gait data has shown promise in detecting important biomechanical features. Therefore, the purpose of this study was to define a new foot strike detection method for a continuum of striking techniques, by applying PCA to joint angle waveforms. In accordance with Newtonian mechanics, it was hypothesized that transient features in the sagittal-plane accelerations of the lower extremity would be linked with the impulsive application of force to the foot at foot strike. Kinematic and kinetic data from treadmill running were selected for 154 subjects, from a database of gait biomechanics. Ankle, knee and hip sagittal plane angular acceleration kinematic curves were chained together to form a row input to a PCA matrix. A linear polynomial was calculated based on PCA scores, and a 10-fold cross-validation was performed to evaluate prediction accuracy against gold-standard foot strike as determined by a 10 N rise in the vertical ground reaction force. Results show 89-94% of all predicted foot strikes were within 4 frames (20 ms) of the gold standard with the largest error being 28 ms. It is concluded that this new foot strike detection is an improvement on existing methods and can be applied regardless of whether the runner exhibits a rearfoot, midfoot, or forefoot strike pattern. Copyright © 2014 Elsevier Ltd. All rights reserved.
Footwear Matters: Influence of Footwear and Foot Strike on Load Rates during Running.
Rice, Hannah M; Jamison, Steve T; Davis, Irene S
2016-12-01
Running with a forefoot strike (FFS) pattern has been suggested to reduce the risk of overuse running injuries, due to a reduced vertical load rate compared with rearfoot strike (RFS) running. However, resultant load rate has been reported to be similar between foot strikes when running in traditional shoes, leading to questions regarding the value of running with a FFS. The influence of minimal footwear on the resultant load rate has not been considered. This study aimed to compare component and resultant instantaneous loading rate (ILR) between runners with different foot strike patterns in their habitual footwear conditions. Twenty-nine injury-free participants (22 men, seven women) ran at 3.13 m·s along a 30-m runway, with their habitual foot strike and footwear condition. Ground reaction force data were collected. Peak ILR values were compared between three conditions; those who habitually run with an RFS in standard shoes, with an FFS in standard shoes, and with an FFS in minimal shoes. Peak resultant, vertical, lateral, and medial ILR were lower (P < 0.001) when running in minimal shoes with an FFS than in standard shoes with either foot strike. When running with an FFS, peak posterior ILR were lower (P < 0.001) in minimal than standard shoes. When running in a standard shoe, peak resultant and component ILR were similar between footstrike patterns. However, load rates were lower when running in minimal shoes with a FFS, compared with running in standard shoes with either foot strike. Therefore, it appears that footwear alters the load rates during running, even with similar foot strike patterns.
Method for Integrated Simulation (MINTSIM)
1976-01-01
sorties allocated to attack SAMs. FAPA = fraction of striking aircraft attacking air bases which attack parked aircraft in the open. TAAB...each striking aircraft. FAS = fraction of striking aircraft attacking air bases which attack sheltered aircraft. (NOTE: FAPA + FAS = 1.0
Conventional Prompt Global Strike and Long-Range Ballistic Missiles: Background and Issues
2013-01-10
and Long-Range Ballistic Missiles Congressional Research Service Forward-Based Global Strike ( FBGS ...they may address the nuclear ambiguity issues raised by long-range ballistic missiles in the CPGS program. Forward-Based Global Strike ( FBGS
NASA Astrophysics Data System (ADS)
Wu, C.; Zhang, P.; Zheng, W.; Wang, H.; Zhang, Z.; Ren, Z.; Zheng, D.; Yu, J.; Wu, G.
2017-12-01
The deformation pattern and strain distribution of the Tian Shan is a hot issue.Previous studies mainly focus on the thrust-fold systems on both sides of Tian Shan, the strike-slip faults within the mountains are rarely reported. The understanding about the deformation characteristics of Tian Shan is not complete for lacking information of these strike-slip faults.Our studies show the NEE trending structures of Maidan fault and Nalati fault in the southwestern Tian Shan are all active during the Holence. These faults are characterized by sinistral strike-slip and thrust movement. The minimum average sinistral strike-slip rate of the Maidan fault is 1.07 ± 0.13 mm/yr. During the late Quaternary, the average shortening rate and sinistral strike-slip rate of the Nalati fault are 2.1 ±0.4 mm/yr and 2.56 ±0.25 mm/yr, respectively . In the interior of the Tian Shan area, two groups of strike-slip faults were developed. The NEE trending faults with sinistral strike-slipmovement, and the NWW trending faults with dextral strike-slip movement show the shape of "X"in geometrical structure. The piedmont thrust faults and the thrust strike-slip faults in the interior mountain constitute the tectonic framework of Tian Shan. Threegroups of active fault systems are the main seismogenic and geological structures, which control the current tectonic deformation pattern of Tian Shan (Figure 1). GPS observation data also showthe similar deformation characteristics with the geological results (Figures 2, 3). In addition to the crustal shortening, there is a certain strike-slip shear movement in the interior of the Tian Shan.The strike-slip rate defined by the geological and GPS data is approximately consistent with each other near the same longitude. We suggest the two groups of strike-slip faults in the interior of mountains is a set of conjugate structures. The whole Tian Shan forms a large flower-structure in a profile view. The complete tectonic deformation of the Tian Shan mountains consists ofthe shortening deformationof the N-S direction and the lateral extrusion of the E-W direction (Figure 2). The late Cenozoic deformation of the Tian Shan mountains is due to the northward subduction of Tarim Block. Although the activedeformation of the Tian Shan decrease eastward, the geological sturcutrein eastern Tian Shan is similar.
Expert anticipatory skill in striking sports: a review and a model.
Müller, Sean; Abernethy, Bruce
2012-06-01
Expert performers in striking sports can hit objects moving at high speed with incredible precision. Exceptionally well developed anticipation skills are necessary to cope with the severe constraints on interception. In this papr we provide a review of the empirical evidence regarding expert interception in striking sports and propose a preliminary model of expert anticipation. Central to the review and the model is the notion that the visual information used to guide the sequential phases of the striking action is systematically different between experts and nonexperts. Knowing the factors that contribute to expert anticipation, and how anticipation may guide skilled performance in striking sports, has practical implications for assessment and training across skill levels.
1992-04-01
Hunger strikes are being used increasingly and not only by those with a political point to make. Whereas in the past, hunger strikes in the United Kingdom seemed mainly to be started by terrorist prisoners for political purposes, the most recent was begun by a Tamil convicted of murder, to protest his innocence. In the later stages of his strike, before calling it off, he was looked after at the Hammersmith Hospital. So it is not only prison doctors who need to know how to handle a hunger strike. The following guidelines, adopted by the 43rd World Medical Assembly in Malta in November 1991, are therefore a timely reminder of the doctor's duties during a hunger strike.
Gomez, Antonio; DeRego, Paul Jeffrey; Ferrell, Patrick Andrew; Thom, Robert Anthony; Trujillo, Joshua J.; Herridge, Brian
2015-09-29
An apparatus for generating seismic waves includes a housing, a strike surface within the housing, and a hammer movably disposed within the housing. An actuator induces a striking motion in the hammer such that the hammer impacts the strike surface as part of the striking motion. The actuator is selectively adjustable to change characteristics of the striking motion and characteristics of seismic waves generated by the impact. The hammer may be modified to change the physical characteristics of the hammer, thereby changing characteristics of seismic waves generated by the hammer. The hammer may be disposed within a removable shock cavity, and the apparatus may include two hammers and two shock cavities positioned symmetrically about a center of the apparatus.
Gomez, Antonio; DeRego, Paul Jeffrey; Ferrel, Patrick Andrew; Thom, Robert Anthony; Trujillo, Joshua J.; Herridge, Brian
2014-08-19
An apparatus for generating seismic waves includes a housing, a strike surface within the housing, and a hammer movably disposed within the housing. An actuator induces a striking motion in the hammer such that the hammer impacts the strike surface as part of the striking motion. The actuator is selectively adjustable to change characteristics of the striking motion and characteristics of seismic waves generated by the impact. The hammer may be modified to change the physical characteristics of the hammer, thereby changing characteristics of seismic waves generated by the hammer. The hammer may be disposed within a removable shock cavity, and the apparatus may include two hammers and two shock cavities positioned symmetrically about a center of the apparatus.
Strike-slip faulting of ridged plains near Valles Marineris, Mars
NASA Astrophysics Data System (ADS)
Schultz, R. A.
1989-10-01
This paper identifies and documents several well-preserved examples of Martian strike-slip faults and examines their relationships to wrinkle-ridges. The strike-slip faulting predates or overlaps periods of wrinkle-ridge growth southeast of Valles Marineris, and some wrinkle ridges may have nucleated and grown as a result of strike-slip displacements along the echelon fault arrays. Lateral displacements of several km inferred along these arrays may be related to tectonism in Tharsis.
Are physicians' strikes ever morally justifiable? A call for a return to tradition.
Mawere, Munyaradzi
2010-08-21
Though physicians strike provides an opportunity to generate more knowledge about the process in which legitimacy of an organization can be restored, it meets with a great deal of resistance not only by the public but from within the medical profession. This paper critically examines the legitimacy of strike by medical doctors heretofore referred to as physicians. Though critically reflecting on strikes of physicians in general, the paper makes more emphasis on Africa where physician strikes are rampant. More importantly, the paper argues that strike implies a failure for everyone in the organization (including the strikers themselves), not only the responsible government or authority. This is because when a strike occurs, an organization/fraternity is subjected to questions, scrutiny and slander. It becomes difficult to decouple what is said, decided and done. Traditionally, all medical fraternities the world-over are committed to acting comfortably to external demands-guaranteeing the patients' lives and public health. By paying attention to external reactions, the medical fraternity adapts and learns what ought and should be done so that it is never again caught in the same messy. At the same time, the fraternity prepares itself for the future strikes. When the fraternity and those outside consider it is doing up to the external expectations, its lost legitimacy is restored. When legitimacy is restored, external pressure like once disturbed water returns to normal.
Goss, Donald L.; Lewek, Michael; Yu, Bing; Ware, William B.; Teyhen, Deydre S.; Gross, Michael T.
2015-01-01
Context The injury incidence rate among runners is approximately 50%. Some individuals have advocated using an anterior–foot-strike pattern to reduce ground reaction forces and injury rates that they attribute to a rear–foot-strike pattern. The proportion of minimalist shoe wearers who adopt an anterior–foot-strike pattern remains unclear. Objective To evaluate the accuracy of self-reported foot-strike patterns, compare negative ankle- and knee-joint angular work among runners using different foot-strike patterns and wearing traditional or minimalist shoes, and describe average vertical-loading rates. Design Descriptive laboratory study. Setting Research laboratory. Patients or Other Participants A total of 60 healthy volunteers (37 men, 23 women; age = 34.9 ± 8.9 years, height = 1.74 ± 0.08 m, mass = 70.9 ± 13.4 kg) with more than 6 months of experience wearing traditional or minimalist shoes were instructed to classify their foot-strike patterns. Intervention(s) Participants ran in their preferred shoes on an instrumented treadmill with 3-dimensional motion capture. Main Outcome Measure(s) Self-reported foot-strike patterns were compared with 2-dimensional video assessments. Runners were classified into 3 groups based on video assessment: traditional-shoe rear-foot strikers (TSR; n = 22), minimalist-shoe anterior-foot strikers (MSA; n = 21), and minimalist-shoe rear-foot strikers (MSR; n = 17). Ankle and knee negative angular work and average vertical-loading rates during stance phase were compared among groups. Results Only 41 (68.3%) runners reported foot-strike patterns that agreed with the video assessment (κ = 0.42, P < .001). The TSR runners demonstrated greater ankle-dorsiflexion and knee-extension negative work than MSA and MSR runners (P < .05). The MSA (P < .001) and MSR (P = .01) runners demonstrated greater ankle plantar-flexion negative work than TSR runners. The MSR runners demonstrated a greater average vertical-loading rate than MSA and TSR runners (P < .001). Conclusions Runners often cannot report their foot-strike patterns accurately and may not automatically adopt an anterior–foot-strike pattern after transitioning to minimalist running shoes. PMID:26098391
Goss, Donald L; Lewek, Michael; Yu, Bing; Ware, William B; Teyhen, Deydre S; Gross, Michael T
2015-02-19
Context : The injury incidence rate among runners is approximately 50%. Some individuals have advocated using an anterior-foot-strike pattern to reduce ground reaction forces and injury rates that they attribute to a rear-foot-strike pattern. The proportion of minimalist shoe wearers who adopt an anterior-foot-strike pattern remains unclear. Objective : To evaluate the accuracy of self-reported foot-strike patterns, compare negative ankle- and knee-joint angular work among runners using different foot-strike patterns and wearing traditional or minimalist shoes, and describe average vertical-loading rates. Design : Descriptive laboratory study. Setting : Research laboratory. Patients or Other Participants : A total of 60 healthy volunteers (37 men, 23 women; age = 34.9 ± 8.9 years, height = 1.74 ± 0.08 m, mass = 70.9 ± 13.4 kg) with more than 6 months of experience wearing traditional or minimalist shoes were instructed to classify their foot-strike patterns. Intervention(s) : Participants ran in their preferred shoes on an instrumented treadmill with 3-dimensional motion capture. Main Outcome Measure(s) : Self-reported foot-strike patterns were compared with 2-dimensional video assessments. Runners were classified into 3 groups based on video assessment: traditional-shoe rear-foot strikers (TSR; n = 22), minimalist-shoe anterior-foot strikers (MSA; n = 21), and minimalist-shoe rear-foot strikers (MSR; n = 17). Ankle and knee negative angular work and average vertical-loading rates during stance phase were compared among groups. Results : Only 41 (68.3%) runners reported foot-strike patterns that agreed with the video assessment (κ = 0.42, P < .001). The TSR runners demonstrated greater ankle-dorsiflexion and knee-extension negative work than MSA and MSR runners (P < .05). The MSA (P < .001) and MSR (P = .01) runners demonstrated greater ankle plantar-flexion negative work than TSR runners. The MSR runners demonstrated a greater average vertical-loading rate than MSA and TSR runners (P < .001). Conclusions : Runners often cannot report their foot-strike patterns accurately and may not automatically adopt an anterior-foot-strike pattern after transitioning to minimalist running shoes.
Collective Bargaining Laws and Teacher Strikes
ERIC Educational Resources Information Center
Colton, David L.
1978-01-01
Several methodological flaws were found in a Public Service Research Council study relating increases in public employee strikes with the adoption of bargaining statutes. A replication, using teachers, suggests some nonstatutory factors that may strongly affect the incidence of teacher strikes. (Author/IRT)
Lightning studies using LDAR and LLP data
NASA Technical Reports Server (NTRS)
Forbes, Gregory S.
1993-01-01
This study intercompared lightning data from LDAR and LLP systems in order to learn more about the spatial relationships between thunderstorm electrical discharges aloft and lightning strikes to the surface. The ultimate goal of the study is to provide information that can be used to improve the process of real-time detection and warning of lightning by weather forecasters who issue lightning advisories. The Lightning Detection and Ranging (LDAR) System provides data on electrical discharges from thunderstorms that includes cloud-ground flashes as well as lightning aloft (within cloud, cloud-to-cloud, and sometimes emanating from cloud to clear air outside or above cloud). The Lightning Location and Protection (LLP) system detects primarily ground strikes from lightning. Thunderstorms typically produce LDAR signals aloft prior to the first ground strike, so that knowledge of preferred positions of ground strikes relative to the LDAR data pattern from a thunderstorm could allow advance estimates of enhanced ground strike threat. Studies described in the report examine the position of LLP-detected ground strikes relative to the LDAR data pattern from the thunderstorms. The report also describes other potential approaches to the use of LDAR data in the detection and forecasting of lightning ground strikes.
Valenzuela, Kevin A.; Lynn, Scott K.; Mikelson, Lisa R.; Noffal, Guillermo J.; Judelson, Daniel A.
2015-01-01
The purpose of this study was to determine the effect of foot strike patterns and converted foot strike patterns on lower limb kinematics and kinetics at the hip, knee, and ankle during a shod condition. Subjects were videotaped with a high speed camera while running a 5km at self-selected pace on a treadmill to determine natural foot strike pattern on day one. Preferred forefoot group (PFFG, n = 10) and preferred rear foot group (PRFG, n = 11) subjects were identified through slow motion video playback (n = 21, age = 22.8±2.2 years, mass = 73.1±14.5 kg, height 1.75 ± 0.10 m). On day two, subjects performed five overground run trials in both their natural and unnatural strike patterns while motion and force data were collected. Data were collected over two days so that foot strike videos could be analyzed for group placement purposes. Several 2 (Foot Strike Pattern –forefoot strike [FFS], rearfoot strike [RFS]) x 2 (Group – PFFG, PRFG) mixed model ANOVAs (p < 0.05) were run on speed, active peak vertical ground reaction force (VGRF), peak early stance and mid stance sagittal ankle moments, sagittal plane hip and knee moments, ankle dorsiflexion ROM, and sagittal plane hip and knee ROM. There were no significant interactions or between group differences for any of the measured variables. Within subject effects demonstrated that the RFS condition had significantly lower (VGRF) (RFS = 2.58 ± .21 BW, FFS = 2.71 ± 0.23 BW), dorsiflexion moment (RFS = -2.6 1± 0.61 Nm·kg-1, FFS = -3.09 ± 0.32 Nm·kg-1), and dorsiflexion range of motion (RFS = 17.63 ± 3.76°, FFS = 22.10 ± 5.08°). There was also a significantly higher peak plantarflexion moment (RFS = 0.23 ± 0.11 Nm·kg-1, FFS = 0.01 ± 0.01 Nm·kg-1), peak knee moment (RFS = 2.61 ± 0.54 Nm·kg-1, FFS = 2.39 ± 0.61 Nm·kg-1), knee ROM (RFS = 31.72 ± 2.79°, FFS = 29.58 ± 2.97°), and hip ROM (RFS = 42.72 ± 4.03°, FFS = 41.38 ± 3.32°) as compared with the FFS condition. This research suggests that acute changes in foot strike patterns during shod running can create alterations in certain lower limb kinematic and kinetic measures that are not dependent on the preferred foot strike pattern of the individual. This research also challenges the contention that the impact transient spike in the vertical ground reaction force curve is only present during a rear foot strike type of running gait. Key points Footstrike pattern changes should be individually considered and implemented based on individual histories/abilities Forefoot strike patterns increase external dorsiflexion moments Rearfoot strike patterns increase external knee flexion moments Recreational shod runners are able to mimic habitual mechanics of different foot strike patterns PMID:25729311
Valenzuela, Kevin A; Lynn, Scott K; Mikelson, Lisa R; Noffal, Guillermo J; Judelson, Daniel A
2015-03-01
The purpose of this study was to determine the effect of foot strike patterns and converted foot strike patterns on lower limb kinematics and kinetics at the hip, knee, and ankle during a shod condition. Subjects were videotaped with a high speed camera while running a 5km at self-selected pace on a treadmill to determine natural foot strike pattern on day one. Preferred forefoot group (PFFG, n = 10) and preferred rear foot group (PRFG, n = 11) subjects were identified through slow motion video playback (n = 21, age = 22.8±2.2 years, mass = 73.1±14.5 kg, height 1.75 ± 0.10 m). On day two, subjects performed five overground run trials in both their natural and unnatural strike patterns while motion and force data were collected. Data were collected over two days so that foot strike videos could be analyzed for group placement purposes. Several 2 (Foot Strike Pattern -forefoot strike [FFS], rearfoot strike [RFS]) x 2 (Group - PFFG, PRFG) mixed model ANOVAs (p < 0.05) were run on speed, active peak vertical ground reaction force (VGRF), peak early stance and mid stance sagittal ankle moments, sagittal plane hip and knee moments, ankle dorsiflexion ROM, and sagittal plane hip and knee ROM. There were no significant interactions or between group differences for any of the measured variables. Within subject effects demonstrated that the RFS condition had significantly lower (VGRF) (RFS = 2.58 ± .21 BW, FFS = 2.71 ± 0.23 BW), dorsiflexion moment (RFS = -2.6 1± 0.61 Nm·kg(-1), FFS = -3.09 ± 0.32 Nm·kg(-1)), and dorsiflexion range of motion (RFS = 17.63 ± 3.76°, FFS = 22.10 ± 5.08°). There was also a significantly higher peak plantarflexion moment (RFS = 0.23 ± 0.11 Nm·kg(-1), FFS = 0.01 ± 0.01 Nm·kg(-1)), peak knee moment (RFS = 2.61 ± 0.54 Nm·kg(-1), FFS = 2.39 ± 0.61 Nm·kg(-1)), knee ROM (RFS = 31.72 ± 2.79°, FFS = 29.58 ± 2.97°), and hip ROM (RFS = 42.72 ± 4.03°, FFS = 41.38 ± 3.32°) as compared with the FFS condition. This research suggests that acute changes in foot strike patterns during shod running can create alterations in certain lower limb kinematic and kinetic measures that are not dependent on the preferred foot strike pattern of the individual. This research also challenges the contention that the impact transient spike in the vertical ground reaction force curve is only present during a rear foot strike type of running gait. Key pointsFootstrike pattern changes should be individually considered and implemented based on individual histories/abilitiesForefoot strike patterns increase external dorsiflexion momentsRearfoot strike patterns increase external knee flexion momentsRecreational shod runners are able to mimic habitual mechanics of different foot strike patterns.
Global strike-slip fault distribution on Enceladus reveals mostly left-lateral faults
NASA Astrophysics Data System (ADS)
Martin, E. S.; Kattenhorn, S. A.
2013-12-01
Within the outer solar system, normal faults are a dominant tectonic feature; however, strike-slip faults have played a role in modifying the surfaces of many icy bodies, including Europa, Ganymede, and Enceladus. Large-scale tectonic deformation in icy shells develops in response to stresses caused by a range of mechanisms including polar wander, despinning, volume changes, orbital recession/decay, diurnal tides, and nonsynchronous rotation (NSR). Icy shells often preserve this record of tectonic deformation as patterns of fractures that can be used to identify the source of stress responsible for creating the patterns. Previously published work on Jupiter's moon Europa found that right-lateral strike-slip faults predominantly formed in the southern hemisphere and left-lateral strike-slip faults in the northern hemisphere. This pattern suggested they were formed in the past by stresses induced by diurnal tidal forcing, and were then rotated into their current longitudinal positions by NSR. We mapped the distribution of strike-slip faults on Enceladus and used kinematic indicators, including tailcracks and en echelon fractures, to determine their sense of slip. Tailcracks are secondary fractures that form as a result of concentrations of stress at the tips of slipping faults with geometric patterns dictated by the slip sense. A total of 31 strike-slip faults were identified, nine of which were right-lateral faults, all distributed in a seemingly random pattern across Enceladus's surface, in contrast to Europa. Additionally, there is a dearth of strike-slip faults within the tectonized terrains centered at 90°W and within the polar regions north and south of 60°N and 60°S, respectively. The lack of strike-slip faults in the north polar region may be explained, in part, by limited data coverage. The south polar terrain (SPT), characterized by the prominent tiger stripes and south polar dichotomy, yielded no discrete strike-slip faults. This does not suggest that the SPT is devoid of shear: previous work has indicated that the tiger stripes may be undergoing strike-slip motions and the surrounding regions may be experiencing shear. The fracture patterns and geologic activity within the SPT have been previously documented to be the result of stresses induced by both NSR and diurnal tidal deformation. As these same mechanisms are the main controls on strike-slip fault patterns on Europa, the lack of a match between strike-slip patterns on Europa and Enceladus is intriguing. The pattern of strike-slip faults on Enceladus suggests a different combination of stress mechanisms is required to produce the observed distributions. We will present models of global stress mechanisms to consider how the global-scale pattern of strike-slip faults on Enceladus may have been produced. This problem will be investigated further by measuring the angles at which tailcracks have formed on Enceladus. Tailcracks produced by simple shear form at 70.5° to the fault. Any deviation from this angle indicates some ratio of concomitant shear and dilation, which may provide insights into elucidating the stresses controlling strike-slip formation on Enceladus.
"Thunderstruck": penetrating thoracic injury from lightning strike.
van Waes, Oscar J F; van de Woestijne, Pieter C; Halm, Jens A
2014-04-01
Lightning strike victims are rarely presented at an emergency department. Burns are often the primary focus. This case report describes the improvised explosive device like-injury to the thorax due to lightning strike and its treatment, which has not been described prior in (kerauno)medicine. Penetrating injury due to blast from lightning strike is extremely rare. These "shrapnel" injuries should however be ruled out in all patients struck by lightning. Copyright © 2013 American College of Emergency Physicians. Published by Mosby, Inc. All rights reserved.
Tanker Structural Analysis for Minor Collisions
1975-12-01
transverse deflections of the stiffened hull may be assumed to vary linearly from the elevation of the forefoot of the striking bow down to zero at the bilge...Transverse de- flections of the stiffened hull may be assumed to vary linearly from the elevation of the forefoot of the striking bow down to zero... Striking Ship CL L-CL - uer panel 0! Forefoot of Bow of Striking Ship C L,’/Y (Ier rane1) 3d Limit of Shearing Plastic Energy TRANSVERSE SECTION AT WEB
Children on hunger strike: child abuse or legitimate protest?
Mok, A.; Nelson, E. A.; Murphy, J.; Hampson, A.; Hendriks, J. H.
1996-01-01
The issue of children on hunger strike (voluntary total fasting) has not been reported before. The World Medical Association Declaration of Tokyo 1975 and the Declaration of Malta 1991 (revised 1992) provide clinicians with guidelines for the management of adult patients on hunger strike but do not mention children. We report the management of 14 Vietnamese children, aged 1 to 12 years, who took part in a hunger strike at a refugee detention centre in Hong Kong. PMID:8597690
Secondary missile injury from lightning strike.
Blumenthal, Ryan
2012-03-01
A 48-year-old-woman was struck dead by lightning on October 24, 2010, in Pretoria, South Africa. The cause of death was due to direct lightning strike. Examination showed secondary missile injury on her legs. This secondary missile (shrapnel) injury was caused by the lightning striking the concrete pavement next to her. Small pieces of concrete were located embedded within the shrapnel wounds. This case report represents the first documented case of secondary missile formation (shrapnel injury) due to lightning strike in the literature.
NASA Astrophysics Data System (ADS)
Cetin, S.; Konca, A. O.; Dogan, U.; Floyd, M.; Karabulut, H.; Ergintav, S.; Ganas, A.; Paradisis, D.; King, R. W.; Reilinger, R. E.
2017-12-01
The 2014 Mw6.9 Gokceada (strike-slip) and 2017 Mw6.3 Lesvos (normal) earthquakes represent two of the set of faults that accommodate the transition from right-lateral strike-slip faulting on the North Anatolian Fault (NAF) to normal faulting along the Gulf of Corinth. The Gokceada earthquake was a purely strike-slip event on the western extension of the NAF where it enters the northern Aegean Sea. The Lesvos earthquake, located roughly 200 km south of Gokceada, occurred on a WNW-ESE-striking normal fault. Both earthquakes respond to the same regional stress field, as indicated by their sub-parallel seismic tension axis and far-field coseismic GPS displacements. Interpretation of GPS-derived velocities, active faults, crustal seismicity, and earthquake focal mechanisms in the northern Aegean indicates that this pattern of complementary faulting, involving WNW-ESE-striking normal faults (e.g. Lesvos earthquake) and SW-NE-striking strike-slip faults (e.g. Gokceada earthquake), persists across the full extent of the northern Aegean Sea. The combination of these two "families" of faults, combined with some systems of conjugate left-lateral strike-slip faults, complement one another and culminate in the purely extensional rift structures that form the large Gulfs of Evvia and Corinth. In addition to being consistent with seismic and geodetic observations, these fault geometries explain the increasing velocity of the southern Aegean and Peloponnese regions towards the Hellenic subduction zone. Alignment of geodetic extension and seismic tension axes with motion of the southern Aegean towards the Hellenic subduction zone suggests a direct association of Aegean extension with subduction, possibly by trench retreat, as has been suggested by prior investigators.
Late Cretaceous through Cenozoic strike-slip tectonics of southwestern Alaska
Miller, M.L.; Bradley, D.C.; Bundtzen, T.K.; McClelland, W.
2002-01-01
New geologic mapping and geochronology show that margin-parallel strike-slip faults on the western limb of the southern Alaska orocline have experienced multiple episodes of dextral motion since ~100 Ma. These faults are on the upper plate of a subduction zone ~350-450 km inboard of the paleotrench. In southwestern Alaska, dextral displacement is 134 km on the Denali fault, at least 88-94 km on the Iditarod-Nixon Fork fault, and perhaps tens of kilometers on the Dishna River fault. The strike-slip regime coincided with Late Cretaceous sedimentation and then folding in the Kuskokwim basin, and with episodes of magmatism and mineralization at ~70, ~60, and ~30 Ma. No single driving mechanism can explain all of the ~95 million-year history of strike-slip faulting. Since ~40 Ma, the observed dextral sense of strike slip has run contrary to the sense of subduction obliquity. This may be explained by northward motion of the Pacific plate driving continental margin slivers into and/or around the oroclinal bend. From 44 to 66 Ma, oroclinal rotation, perhaps involving large-scale flexural slip, may have been accompanied by westward escape of crustal blocks along strike-slip faults. However, reconstructions of this period involve unproven assumptions about the identity of the subducting plate, the position of subducting ridges, and the exact timing of oroclinal bending, thus obscuring the driving mechanisms of strike slip. Prior to 66 Ma, oblique subduction is the most plausible driving mechanism for dextral strike slip. Cumulative displacement on all faults of the western limb of the orocline is at least 400 km, about half that on the eastern limb; this discrepancy might be explained by a combination of thrusting and unrecognized strike-slip faulting.
Effects of footwear and strike type on running economy.
Perl, Daniel P; Daoud, Adam I; Lieberman, Daniel E
2012-07-01
This study tests if running economy differs in minimal shoes versus standard running shoes with cushioned elevated heels and arch supports and in forefoot versus rearfoot strike gaits. We measured the cost of transport (mL O(2)·kg(-1)·m(-1)) in subjects who habitually run in minimal shoes or barefoot while they were running at 3.0 m·s(-1) on a treadmill during forefoot and rearfoot striking while wearing minimal and standard shoes, controlling for shoe mass and stride frequency. Force and kinematic data were collected when subjects were shod and barefoot to quantify differences in knee flexion, arch strain, plantar flexor force production, and Achilles tendon-triceps surae strain. After controlling for stride frequency and shoe mass, runners were 2.41% more economical in the minimal-shoe condition when forefoot striking and 3.32% more economical in the minimal-shoe condition when rearfoot striking (P < 0.05). In contrast, forefoot and rearfoot striking did not differ significantly in cost for either minimal- or standard-shoe running. Arch strain was not measured in the shod condition but was significantly greater during forefoot than rearfoot striking when barefoot. Plantar flexor force output was significantly higher in forefoot than in rearfoot striking and in barefoot than in shod running. Achilles tendon-triceps surae strain and knee flexion were also lower in barefoot than in standard-shoe running. Minimally shod runners are modestly but significantly more economical than traditionally shod runners regardless of strike type, after controlling for shoe mass and stride frequency. The likely cause of this difference is more elastic energy storage and release in the lower extremity during minimal-shoe running.
Comparison of muscle synergies for running between different foot strike patterns
Nishida, Koji; Hagio, Shota; Kibushi, Benio; Moritani, Toshio; Kouzaki, Motoki
2017-01-01
It is well known that humans run with a fore-foot strike (FFS), a mid-foot strike (MFS) or a rear-foot strike (RFS). A modular neural control mechanism of human walking and running has been discussed in terms of muscle synergies. However, the neural control mechanisms for different foot strike patterns during running have been overlooked even though kinetic and kinematic differences between different foot strike patterns have been reported. Thus, we examined the differences in the neural control mechanisms of human running between FFS and RFS by comparing the muscle synergies extracted from each foot strike pattern during running. Muscle synergies were extracted using non-negative matrix factorization with electromyogram activity recorded bilaterally from 12 limb and trunk muscles in ten male subjects during FFS and RFS running at different speeds (5–15 km/h). Six muscle synergies were extracted from all conditions, and each synergy had a specific function and a single main peak of activity in a cycle. The six muscle synergies were similar between FFS and RFS as well as across subjects and speeds. However, some muscle weightings showed significant differences between FFS and RFS, especially the weightings of the tibialis anterior of the landing leg in synergies activated just before touchdown. The activation patterns of the synergies were also different for each foot strike pattern in terms of the timing, duration, and magnitude of the main peak of activity. These results suggest that the central nervous system controls running by sending a sequence of signals to six muscle synergies. Furthermore, a change in the foot strike pattern is accomplished by modulating the timing, duration and magnitude of the muscle synergy activity and by selectively activating other muscle synergies or subsets of the muscle synergies. PMID:28158258
NASA Astrophysics Data System (ADS)
Beardsley, A. G.; Avé Lallemant, H. G.
2005-12-01
The Leeward Antilles island arc is located offshore northern Venezuela and includes Aruba, Curaçao, and Bonaire (ABCs). The ABCs trend WNW-ESE parallel to the obliquely convergent Caribbean-South American plate boundary zone. Field work on the ABCs has provided new structural data supporting a minimum of 90° clockwise rotation of the islands within the diffuse plate boundary zone. Analysis of faulting, bedding, and cleavages suggest three phases of deformation (D1-D3). The oldest phase of deformation, D1, is characterized by northeast trending normal faults, northwest trending fold axes and cleavages, and northeast striking dextral strike-slip faults. East striking sinstral strike-slip faults are rare. The second phase of deformation, D2, is represented by west-northwest trending thrust faults, north-northeast striking normal faults, northwest trending dextral strike-slip faults, and northeast striking sinstral strike-slip faults. Finally, the youngest phase of deformation, D3, is characterized by northeast striking thrust faults, northwest striking normal faults, east-west dextral strike-slip faults, and north-northwest sinstral strike-slip faults. Quartz and calcite veins were also studied on the ABCs. Cross-cutting relationships in outcrop suggest three phases of veining (V1-V3). The oldest veins, V1, trend northeastward; V2 veins trend northward; and the youngest veins, V3, trend northwestward. Additionally, joints were measured on the ABCs. On Bonaire and Curaçao, joints trend approximately northeast while joints on Aruba are almost random with a slight preference for west-northwest. Fluid inclusion analysis of quartz and calcite veins provides additional information about the pressure and temperature conditions of the deformation phases. Preliminary results from the earliest veins (V1) show a single deformational event on Aruba and Bonaire. On Bonaire, they exhibit both hydrostatic and lithostatic pressure conditions. This new data supports three stages of deformation accompanied by rotation of the ABCs. The structures identified suggest a clockwise rotation of the principal stress orientation since the Late Cretaceous. D1 deformation and rotation occurred at the southeastern Caribbean plate margin beginning approximately 73 Ma on Aruba. Arc-parallel strike-slip motion rotated the islands clockwise 90° Internal deformation features of the island blocks are consistent with an obliquely convergent plate boundary. D2 deformation is characterized by clockwise block rotation facilitated by dextral strike-slip faults defining the northern and southern boundaries of the diffuse plate boundary zone. Most likely, D2 correlates to the Eocene change in plate motions due to convergence between North and South America, approximately 55 Ma. The youngest phase of deformation and rotation, D3, happens along the arcuate South Caribbean Deformed Belt. Since approximately 25 Ma, rotation and development of northwest trending pull-apart basins between the ABCs progressed. Northeastward motion of the Maracaibo block may also contribute to recent rotation of the island arc.
Variations in otological presentation of lightning strike victims: Clinical report of 3 patients.
Kılıç, Erbil; Genç, Hakan; Aydın, Ümit; Aşık, Burak; Satar, Bülent
2017-03-01
Lightning strike can cause fatal or nonfatal injuries. Some nonfatal injuries are associated with otological symptoms and findings. Conductive hearing loss due to rupture of the tympanic membrane is the most common audiovestibular lesion of lightning strike. Various forms of sensorineural hearing loss and dizziness have also been reported. Presently described are 3 cases of lightning strike injury. First patient had mid-frequency hearing loss in right ear and high frequency sensorineural hearing loss in left ear. Second patient had high frequency sensorineural hearing loss in left ear, and the third had peripheral facial palsy with perilymphatic fistula on same side. This is the first documented case of mid-frequency hearing loss occurring after lightning strike.
DOT National Transportation Integrated Search
2008-10-23
The U.S. Department of Agriculture, through an interagency agreement with the Federal Aviation Administration, : compiles a database of all reported wildlife strikes to U.S. civil aircraft and to foreign carriers experiencing strikes : in the USA. We...
NASA Technical Reports Server (NTRS)
Llewellyn, J. A.
1967-01-01
The Launch Complex 37 lightning strike of July 27, 1967, was reviewed and compared to a similar incident on the Gemini Program. Available data indicate little likelihood of damaging currents having been present in SA-204 Launch Vehicle or the ground equipment during the July 27th incident. Based on the results of subsystem and system testing after the strike, anticipated results of future testing, the six months elapsed time between the strike-and launch, and the fact that much of the critical airborne electrical/electronic equipment has been removed since the strike for other reasons, no new actions are considered necessary at this time in the Gemini case, significant failures occurred in both airborne and ground circuits. Due to the resultant semi, condlictor uncertainty, and the relatively' short time prior to planned launch, all critical airborne components containing semiconduetors were replaced, and a sophisticated data comparison task was implemented.
Leap and strike kinetics of an acoustically 'hunting' barn owl (Tyto alba).
Usherwood, James R; Sparkes, Emily L; Weller, Renate
2014-09-01
Barn owls are effective hunters of small rodents. One hunting technique is a leap from the ground followed by a brief flight and a plummeting 'strike' onto an acoustically targeted - and potentially entirely hidden - prey. We used forceplate measurements to derive kinetics of the leap and strike. Leaping performance was similar to reported values for guinea fowl. This is likely achieved despite the owl's considerably smaller size because of its relatively long legs and use of wing upstroke. Strikes appear deliberately forceful: impulses could have been spread over larger periods during greater deflections of the centre of mass, as observed in leaping and an alighting landing measurement. The strike, despite forces around 150 times that of a mouse body weight, is not thought to be crucial to the kill; rather, forceful strikes may function primarily to enable rapid penetration of leaf litter or snow cover, allowing grasping of hidden prey. © 2014. Published by The Company of Biologists Ltd.
Li, Shudong; Zhang, Yan; Gu, Yaodong; Ren, James
2017-12-01
Due to the limitations of experimental approaches, comparison of the internal deformation and stresses of the human man foot between forefoot and rearfoot landing is not fully established. The objective of this work is to develop an effective FE modelling approach to comparatively study the stresses and energy in the foot during forefoot strike (FS) and rearfoot strike (RS). The stress level and rate of stress increase in the Metatarsals are established and the injury risk between these two landing styles is evaluated and discussed. A detailed subject specific FE foot model is developed and validated. A hexahedral dominated meshing scheme was applied on the surface of the foot bones and skin. An explicit solver (Abaqus/Explicit) was used to stimulate the transient landing process. The deformation and internal energy of the foot and stresses in the metatarsals are comparatively investigated. The results for forefoot strike tests showed an overall higher average stress level in the metatarsals during the entire landing cycle than that for rearfoot strike. The increase rate of the metatarsal stress from the 0.5 body weight (BW) to 2 BW load point is 30.76% for forefoot strike and 21.39% for rearfoot strike. The maximum rate of stress increase among the five metatarsals is observed on the 1st metatarsal in both landing modes. The results indicate that high stress level during forefoot landing phase may increase potential of metatarsal injuries. Copyright © 2017 Elsevier Ltd. All rights reserved.
Changes in gluteal muscle forces with alteration of footstrike pattern during running.
Vannatta, Charles Nathan; Kernozek, Thomas W; Gheidi, Naghmeh
2017-10-01
Gait retraining is a common form of treatment for running related injuries. Proximal factors at the hip have been postulated as having a role in the development of running related injuries. How altering footstrike affects hip muscles forces and kinematics has not been described. Thus, we aimed to quantify differences in hip muscle forces and hip kinematics that may occur when healthy runners are instructed to alter their foot strike pattern from their habitual rear-foot strike to a forefoot strike. This may gain insight on the potential etiology and treatment methods of running related lower extremity injury. Twenty-five healthy female runners completed a minimum of 10 running trials in a controlled laboratory setting under rear-foot strike and instructed forefoot strike conditions. Kinetic and kinematic data were used in an inverse dynamic based static optimization to estimate individual muscle forces during running. Within subject differences were investigated using a repeated measures multi-variate analysis of variance. Peak gluteus medius and minimus and hamstring forces were reduced while peak gluteus maximus force was increased when running with an instructed forefoot strike pattern. Peak hip adduction, hip internal rotation, and heel-COM distance were also reduced. Therefore, instructing habitual rearfoot strike runners to run with a forefoot strike pattern resulted in changes in peak gluteal and hamstring muscle forces and hip kinematics. These changes may be beneficial to the development and treatment of running related lower extremity injury. Copyright © 2017 Elsevier B.V. All rights reserved.
Rein, Robert; Nonaka, Tetsushi; Bril, Blandine
2014-01-01
The earliest direct evidence for tool-use by our ancestors are 2.6 million year old stone tools from Africa. These earliest artifacts show that, already, early hominins had developed the required advanced movement skills and cognitive capacities to manufacture stone tools. Currently, it is not well understood, however, which specific movement skills are required for successful stone knapping and accordingly it is unknown how these skills emerged during early hominin evolution. In particular, it is not clear which striking movements are indicative of skilled performance, how striking movement patterns vary with task and environmental constraints, and how movement patterns are passed on within social groups. The present study addresses these questions by investigating striking movement patterns and striking variability in 18 modern stone knappers (nine experienced and nine novices). The results suggest that no single movement pattern characterizes successful stone knapping. Participants showed large inter-individual movement variability of the elementary knapping action irrespective of knapping experience and knapping performance. Changes in task- and environmental constraints led knappers to adapt their elementary striking actions using a combination of individual and common strategies. Investigation of striking pattern similarities within social groups showed only partial overlap of striking patterns across related individuals. The results therefore suggest that striking movement patterns in modern stone knappers are largely specific to the individual and movement variability is not indicative of knapping performance. The implications of these results for the development of percussive traditions are discussed. PMID:25426630
Structures associated with strike-slip faults that bound landslide elements
Fleming, R.W.; Johnson, A.M.
1989-01-01
Large landslides are bounded on their flanks and on elements within the landslides by structures analogous to strike-slip faults. We observed the formation of thwse strike-slip faults and associated structures at two large landslides in central Utah during 1983-1985. The strike-slip faults in landslides are nearly vertical but locally may dip a few degrees toward or away from the moving ground. Fault surfaces are slickensided, and striations are subparallel to the ground surface. Displacement along strike-slip faults commonly produces scarps; scarps occur where local relief of the failure surface or ground surface is displaced and becomes adjacent to higher or lower ground, or where the landslide is thickening or thinning as a result of internal deformation. Several types of structures are formed at the ground surface as a strike-slip fault, which is fully developed at some depth below the ground surface, propagates upward in response to displacement. The simplest structure is a tension crack oriented at 45?? clockwise or counterclockwise from the trend of an underlying right- or left-lateral strike-slip fault, respectively. The tension cracks are typically arranged en echelon with the row of cracks parallel to the trace of the underlying strike-slip fault. Another common structure that forms above a developing strike-slip fault is a fault segment. Fault segments are discontinuous strike-slip faults that contain the same sense of slip but are turned clockwise or counterclockwise from a few to perhaps 20?? from the underlying strike-slip fault. The fault segments are slickensided and striated a few centimeters below the ground surface; continued displacement of the landslide causes the fault segments to open and a short tension crack propagates out of one or both ends of the fault segments. These structures, open fault segments containing a short tension crack, are termed compound cracks; and the short tension crack that propagates from the tip of the fault segment is typically oriented 45?? to the trend of the underlying fault. Fault segments are also typically arranged en echelon above the upward-propagating strike-slip fault. Continued displacement of the landslide causes the ground to buckle between the tension crack portions of the compound cracks. Still more displacement produces a thrust fault on one or both limbs of the buckle fold. These compressional structures form at right angles to the short tension cracks at the tips of the fault segments. Thus, the compressional structures are bounded on their ends by one face of a tension crack and detached from underlying material by thrusting or buckling. The tension cracks, fault segments, compound cracks, folds, and thrusts are ephemeral; they are created and destroyed with continuing displacement of the landslide. Ultimately, the structures are replaced by a throughgoing strike-slip fault. At one landslide, we observed the creation and destruction of the ephemeral structures as the landslide enlarged. Displacement of a few centimeters to about a decimeter was sufficient to produce scattered tension cracks and fault segments. Sets of compound cracks with associated folds and thrusts were produced by displacements of up to 1 m, and 1 to 2 m of displacement was required to produce a throughgoing strike-slip fault. The type of first-formed structure above an upward-propagating strike-slip fault is apparently controlled by the rheology of the material. Brittle material such as dry topsoil or the compact surface of a gravel road produces echelon tension cracks and sets of tension cracks and compressional structures, wherein the cracks and compressional structures are normal to each other and 45?? to the strike-slip fault at depth. First-formed structures in more ductile material such as moist cohesive soil are fault segments. In very ductile material such as soft clay and very wet soil in swampy areas, the first-formed structure is a throughgoing strike-slip fault. There are othe
14 CFR 35.38 - Lightning strike.
Code of Federal Regulations, 2011 CFR
2011-01-01
... STANDARDS: PROPELLERS Tests and Inspections § 35.38 Lightning strike. The applicant must demonstrate, by tests, analysis based on tests, or experience on similar designs, that the propeller can withstand a lightning strike without causing a major or hazardous propeller effect. The limit to which the propeller has...
14 CFR 35.38 - Lightning strike.
Code of Federal Regulations, 2010 CFR
2010-01-01
... STANDARDS: PROPELLERS Tests and Inspections § 35.38 Lightning strike. The applicant must demonstrate, by tests, analysis based on tests, or experience on similar designs, that the propeller can withstand a lightning strike without causing a major or hazardous propeller effect. The limit to which the propeller has...
14 CFR 35.38 - Lightning strike.
Code of Federal Regulations, 2013 CFR
2013-01-01
... STANDARDS: PROPELLERS Tests and Inspections § 35.38 Lightning strike. The applicant must demonstrate, by tests, analysis based on tests, or experience on similar designs, that the propeller can withstand a lightning strike without causing a major or hazardous propeller effect. The limit to which the propeller has...
14 CFR 35.38 - Lightning strike.
Code of Federal Regulations, 2012 CFR
2012-01-01
... STANDARDS: PROPELLERS Tests and Inspections § 35.38 Lightning strike. The applicant must demonstrate, by tests, analysis based on tests, or experience on similar designs, that the propeller can withstand a lightning strike without causing a major or hazardous propeller effect. The limit to which the propeller has...
14 CFR 35.38 - Lightning strike.
Code of Federal Regulations, 2014 CFR
2014-01-01
... STANDARDS: PROPELLERS Tests and Inspections § 35.38 Lightning strike. The applicant must demonstrate, by tests, analysis based on tests, or experience on similar designs, that the propeller can withstand a lightning strike without causing a major or hazardous propeller effect. The limit to which the propeller has...
DOT National Transportation Integrated Search
2010-11-10
The U.S. Department of Agriculture, through an interagency agreement with the Federal Aviation Administration, compiles a database of all reported wildlife strikes to U.S. civil aircraft and to foreign carriers experiencing strikes in the USA. We hav...
76 FR 36996 - Extension of Time for Filing Returns
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-24
... overall taxpayer burden by providing an extension period that strikes the most reasonable balance for... the overall burden on taxpayers and strikes the most reasonable balance for all affected taxpayers... successful and continues to strike the right balance in reducing overall taxpayer burden since the proposed...
Origin and structure of major orogen-scale exhumed strike-slip
NASA Astrophysics Data System (ADS)
Cao, Shuyun; Neubauer, Franz
2016-04-01
The formation of major exhumed strike-slip faults represents one of the most important dynamic processes affecting the evolution of the Earth's lithosphere and surface. Detailed models of the potential initiation and properties and architecture of orogen-scale exhumed strike-slip faults and how these relate to exhumation are rare. In this study, we deal with key properties controlling the development of major exhumed strike-slip fault systems, which are equivalent to the deep crustal sections of active across fault zones. We also propose two dominant processes for the initiation of orogen-scale exhumed strike-slip faults: (1) pluton-controlled and (2) metamorphic core complex-controlled strike-slip faults. In these tectonic settings, the initiation of faults occurs by rheological weakening along hot-to-cool contacts and guides the overall displacement and ultimate exhumation. These processes result in a specific thermal and structural architecture of such faults. These types of strike-slip dominated fault zones are often subparallel to mountain ranges and expose a wide variety of mylonitic, cataclastic and non-cohesive fault rocks, which were formed at different structural levels of the crust during various stages of faulting. The high variety of distinctive fault rocks is a potential evidence for recognition of these types of strike-slip faults. Exhumation of mylonitic rocks is, therefore, a common feature of such reverse oblique-slip strike-slip faults, implying major transtensive and/or transpressive processes accompanying pure strike-slip motion during exhumation. Some orogen-scale strike-slip faults nucleate and initiate along rheologically weak zones, e.g. at granite intrusions, zones of low-strength minerals, thermally weakened crust due to ascending fluids, and lateral borders of hot metamorphic core complexes. A further mechanism is the juxtaposition of mechanically strong mantle lithosphere to hot asthenosphere in continental transform faults (e.g., San Andreas Fault, Alpine Fault in New Zealand) and transtensional rift zones such as the East African rift. In many cases, subsequent shortening exhumes such faults from depth to the surface. A major aspect of many exhumed strike-slip faults is its lateral thermal gradient induced by the juxtaposition of hot and cool levels of the crust controlling relevant properties of such fault zones, e.g. the overall fault architecture (e.g., fault core, damage zone, shear lenses, fault rocks) and the thermal structure. These properties and the overall fault architecture include strength of fault rocks, permeability and porosity, the hydrological regime, as well as the nature and origin of circulating hydrothermal fluids.
NASA Astrophysics Data System (ADS)
Meyer, Sven Erik; Passchier, Cees; Abu-Alam, Tamer; Stüwe, Kurt
2014-05-01
Metamorphic core complexes usually develop as extensional features during continental crustal thinning, such as the Basin and Range and the Aegean Terrane. The Najd fault system in Saudi Arabia is a 2000 km-long and 400 km-wide complex network of crustal-scale strike-slip shear zones in a Neoproterozoic collision zone. Locally, the anastomosing shear zones lead to exhumation of lower crustal segments and represent a new kinematic model for the development of core complexes. We report on two such structures: the Qazaz complex in Saudi Arabia and the Hafafit complex in Egypt. The 15 km-wide Qazaz complex is a triangular dome of gently dipping mylonitic foliations within the 140 km-long sinistral strike-slip Qazaz mylonite zone. The gneissic dome consists of high-grade rocks, surrounded by low-grade metasediments and metavolcanics. The main SE-trending strike-slip Qazaz shear zone splits southwards into two branches around the gneiss dome: the western branch is continuous with the shallow dipping mylonites of the dome core, without overprinting, and changes by more than 90 degrees from a NS-trending strike-slip zone to an EW-trending 40 degree south-dipping detachment that bounds the gneiss dome to the south. The eastern SE-trending sinistral strike-slip shear zone branch is slightly younger and transects the central dome fabrics. The gneiss dome appears to have formed along a jog in the strike-slip shear zone during 40 km of horizontal strike-slip motion, which caused local exhumation of lower crustal rocks by 25 km along the detachment. The eastern shear zone branch formed later during exhumation, transacted the gneiss dome and offset the two parts by another 70 km. The Hafafit core complex in Egypt is of similar shape and size to the Qazaz structure, but forms the northern termination of a sinistral strike-slip zone that is at least 100 km in length. This zone may continue into Saudi Arabia as the Ajjaj shear zone for another 100 km. The NW trending strike slip mylonite zone grades into a gently N-dipping detachment to the west which accommodated strike slip by exhumation of high-grade lower crustal rocks. The Qazaz and the Hafafit Domes are similar, mirror-image structures with small differences in the accommodating shear zones. It is likely that these types of strike-slip related oblique core complexes are common in the Arabian Nubian shield, and possibly elsewhere.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-01-12
... exchange. Similar reciprocity currently is permitted with the Exchange's $1 Strike Program, $.50 Strike... consistent with the protection of investors and the public interest because the proposed reciprocity provision is similar to reciprocity provisions in place for other option strike price programs,\\9\\ which...
77 FR 58761 - Airworthiness Directives; Empresa Brasileira de Aeronautica S.A. (EMBRAER) Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2012-09-24
... lightning strikes from causing certain parts to contact the airplane pitch control system, which could... lightning strike effects [could cause certain parts to contact the airplane pitch control system, which... a lightning strike hitting an airplane tail boom causing certain rear bulkhead parts to jam an...
[Labour History in Manitoba, Canada.
ERIC Educational Resources Information Center
Manitoba Social Science Teacher, 1994
1994-01-01
Devoted to the Winnipeg General Strike in 1919, this document provides social science teachers with details of the strike as well as general information on teaching about unions, labor, and working-class history. The first article, "The Winnipeg General Strike" (Doug Smith), presents the events during and prior to the Winnipeg General…
37 CFR 1.121 - Manner of making amendments in applications.
Code of Federal Regulations, 2010 CFR
2010-07-01
... strike-through except that double brackets placed before and after the deleted characters may be used to... shown by being placed within double brackets if strike-through cannot be easily perceived; (iii) The... deleted must not be presented with strike-through or placed within double brackets. The instruction to...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-15
... striking and ranking the arbitrators on the lists. Currently, FINRA sends the parties lists of available... arbitrators from the parties' ranking lists. However, after each side exercises its strikes, typically only... arbitrators during the ranking and striking stage of the arbitrator appointment process. In instances where...
Beyond the basics: lightning-strike injuries.
Mistovich, Joseph J; Krost, William S; Limmer, Daniel D
2008-03-01
It is estimated that a lightning flash occurs approximately 8 million times per day throughout the world. Most strikes are benign and cause little damage to property and physical structures; however, when lightning strikes a person or group of people, it is a significant medical and potentially traumatic event that could lead to immediate death or permanent disability. By understanding some basic physics of lightning and pathophysiology of injuries associated with lightning strikes, EMS providers will be better prepared to identify assessment findings, anticipate complications and provide effective emergency care.
A Comparison of 2 Current-Issue Army Boots.
2000-01-01
at 3.5 mph, mean (SD) 32 21 .Maximum heel- strike vertical force (N) while walking at 3.5 mph, mean (SD) 33 22 Maximum heel- strike braking force...while running at 6.5 mph, mean (SD) 38 34 Maximum force on the hip (N) while running at 6.5 mph, mean (SD) 38 35 Maximum vertical heel- strike force (N...during 6.5 mph running, mean (SD) 39 36. Maximum heel- strike braking force (N) while running at 6.5 mph, mean (SD) 39 37. Maximum vertical push
Accuracy of the Peak (TM) Two and Three-Dimensional Videography Analysis for a Rearfoot Model
1993-01-01
of gait. "Pronation occurs in the stance phase of gait to I allow for shock absorption, ground terrain changes, and equilibrium.""I At heel strike , 80...5 percent of the body weight is directly over the calcaneus. The calcaneus is in slight inversion at heel strike . 16 5 There are four major forces...acting on the foot at heel strike or toe strike . The forces are compression, rotation, anterior shear, and medial shear. " Normal pronation is U required
Bird Strike Risk for Space Launch Vehicles
NASA Technical Reports Server (NTRS)
Hales, Christy; Czech, Matthew
2017-01-01
Within seconds after liftoff of the Space Shuttle during mission STS-114, a turkey vulture impacted the vehicle's external tank. The contact caused no apparent damage to the shuttle, but the incident led NASA to consider the potential consequences of bird strikes during a shuttle launch. The environment at Kennedy Space Center provides unique bird strike challenges due to the Merritt Island National Wildlife Refuge and the Atlantic Flyway bird migration routes. This presentation will outline an approach for estimating risk resulting from bird strikes to space launch vehicles. The migration routes, types of birds present, altitudes of those birds, exposed area of the launch vehicle, and its capability to withstand impacts all affect the risk due to bird strike. Lessons learned, challenges over lack of data, and significant risk contributors will be discussed.
NASA Astrophysics Data System (ADS)
Rohayat, O. R.; Wicaksono, R. A.; Daud, Y.
2018-03-01
In this study, we determined the main direction of geoelectric strike in the southern part of the Wayang Windu geothermal field using magnetotellurics (MT) data. The strike direction was obtained by analyzing data using impedance polar and Zstrike rose diagram. We investigated 51 MT data at different sites of the southern part of the Wayang Windu geothermal field. Determination of geoelectric strike direction is important since the strike is the rotation references in MT data processing. Our findings had pointed out that the geoelectric strike direction in this study area is in accordance with the direction of geological structure and has a good correlation with structures delineated from 3D MT inversion model.
Melcher, Daniel A; Paquette, Max R; Schilling, Brian K; Bloomer, Richard J
2017-12-01
Research has focused on the effects of acute strike pattern modifications on lower extremity joint stiffness and running economy (RE). Strike pattern modifications on running biomechanics have mostly been studied while runners complete short running bouts. This study examined the effects of an imposed forefoot strike (FFS) on RE and ankle and knee joint stiffness before and after a long run in habitual rearfoot strike (RFS) runners. Joint kinetics and RE were collected before and after a long run. Sagittal joint kinetics were computed from kinematic and ground reaction force data that were collected during over-ground running trials in 13 male runners. RE was measured during treadmill running. Knee flexion range of motion, knee extensor moment and ankle joint stiffness were lower while plantarflexor moment and knee joint stiffness were greater during imposed FFS compared with RFS. The long run did not influence the difference in ankle and knee joint stiffness between strike patterns. Runners were more economical during RFS than imposed FFS and RE was not influenced by the long run. These findings suggest that using a FFS pattern towards the end of a long run may not be mechanically or metabolically beneficial for well-trained male RFS runners.
Trinh, T X; Heinke, S; Rode, C; Schenkl, S; Hubig, M; Mall, G; Muggenthaler, Holger
2018-03-01
In blunt force trauma to the head caused by attacks with blunt instruments, contact forces can be estimated based on the conservation of momentum if impact velocities are known. The aims of this work were to measure maximum striking velocities and to examine the influence of rod parameters such as rod mass and length as well as volunteer parameters such as sex, age, body height, body mass, body mass index and the average amount of physical exercise. Steel rods with masses of 500, 1000 and 1500 g as well as lengths of 40, 65 and 90 cm were exemplarily tested as blunt instruments. Twenty-nine men and 22 women participated in this study. Each volunteer performed several vertical strikes with the steel rods onto a passive immobile target. Maximum striking velocities were measured by means of a Qualisys motion capture system using high-speed cameras and infrared light. Male volunteers achieved maximum striking velocities between 14.0 and 35.5 m/s whereas female volunteers achieved values between 10.4 and 28.3 m/s. Results show that maximum striking velocities increased with smaller rod masses and less consistently with higher rod lengths. Statistically significant influences were found in the volunteers' sex and average amount of physical exercise.
Physicians and strikes: can a walkout over the malpractice crisis be ethically justified?
Fiester, Autumn
2004-01-01
Malpractice insurance rates have created a crisis in American medicine. Rates are rising and reimbursements are not keeping pace. In response, physicians in the states hardest hit by this crisis are feeling compelled to take political action, and the current action of choice seems to be physician strikes. While the malpractice insurance crisis is acknowledged to be severe, does it justify the extreme action of a physician walkout? Should physicians engage in this type of collective action, and what are the costs to patients and the profession when such action is taken? I will offer three related arguments against physician strikes that constitute a prima facie prohibition against such action: first, strikes are intended to cause harm to patients; second, strikes are an affront to the physician-patient relationship; and, third, strikes risk decreasing the public's respect for the medical profession. As with any prima facie obligation, there are justifying conditions that may override the moral prohibition, but I will argue that the current malpractice crisis does not rise to the level of such a justifying condition. While the malpractice crisis demands and justifies a political response on the part of the nation's physicians, strikes and slow-downs are not an ethically justified means to the legitimate end of controlling insurance costs.
NASA Astrophysics Data System (ADS)
Busby, Cathy J.; Bassett, Kari N.
2007-09-01
The three-dimensional arrangement of volcanic deposits in strike-slip basins is not only the product of volcanic processes, but also of tectonic processes. We use a strike-slip basin within the Jurassic arc of southern Arizona (Santa Rita Glance Conglomerate) to construct a facies model for a strike-slip basin dominated by volcanism. This model is applicable to releasing-bend strike-slip basins, bounded on one side by a curved and dipping strike-slip fault, and on the other by curved normal faults. Numerous, very deep unconformities are formed during localized uplift in the basin as it passes through smaller restraining bends along the strike-slip fault. In our facies model, the basin fill thins and volcanism decreases markedly away from the master strike-slip fault (“deep” end), where subsidence is greatest, toward the basin-bounding normal faults (“shallow” end). Talus cone-alluvial fan deposits are largely restricted to the master fault-proximal (deep) end of the basin. Volcanic centers are sited along the master fault and along splays of it within the master fault-proximal (deep) end of the basin. To a lesser degree, volcanic centers also form along the curved faults that form structural highs between sub-basins and those that bound the distal ends of the basin. Abundant volcanism along the master fault and its splays kept the deep (master fault-proximal) end of the basin overfilled, so that it could not provide accommodation for reworked tuffs and extrabasinally-sourced ignimbrites that dominate the shallow (underfilled) end of the basin. This pattern of basin fill contrasts markedly with that of nonvolcanic strike-slip basins on transform margins, where clastic sedimentation commonly cannot keep pace with subsidence in the master fault-proximal end. Volcanic and subvolcanic rocks in the strike-slip basin largely record polygenetic (explosive and effusive) small-volume eruptions from many vents in the complexly faulted basin, referred to here as multi-vent complexes. Multi-vent complexes like these reflect proximity to a continuously active fault zone, where numerous strands of the fault frequently plumb small batches of magma to the surface. Releasing-bend extension promotes small, multivent styles of volcanism in preference to caldera collapse, which is more likely to form at releasing step-overs along a strike-slip fault.
Marshak, S.; Nelson, W.J.; McBride, J.H.
2003-01-01
The continental interior platform of the United States is that part of the North American craton where a thin veneer of Phanerozoic strata covers Precambrian crystalline basement. N- to NE-trending and W- to NW-trending fault zones, formed initially by Proterozoic/Cambrian rifting, break the crust of the platform into rectilinear blocks. These zones were reactivated during the Phanerozoic, most notably in the late Palaeozoic Ancestral Rockies event and the Mesozoic-Cenozoic Laramide orogeny - some remain active today. Dip-slip reactivation can be readily recognized in cross section by offset stratigraphic horizons and monoclinal fault-propagation folds. Strike-slip displacement is hard to document because of poor exposure. Through offset palaeochannels, horizontal slip lineations, and strain at fault bends locally demonstrate strike-slip offset, most reports of strike-slip movements for interior-platform faults are based on occurrence of map-view belts of en echelon faults and anticlines. Each belt overlies a basement-penetrating master fault, which typically splays upwards into a flower structure. In general, both strike-slip and dip-slip components of displacement occur in the same fault zone, so some belts of en echelon structures occur on the flanks of monoclinal folds. Thus, strike-slip displacement represents the lateral components of oblique fault reactivation: dip-slip and strike-slip components are the same order of magnitude (tens of metres to tens of kilometres). Effectively, faults with strike-slip components of displacement act as transfers accommodating jostling of rectilinear crustal blocks. In this context, the sense of slip on an individual strike-slip fault depends on block geometry, not necessarily on the trajectory of regional ??1. Strike-slip faulting in the North American interior differs markedly from that of southern and central Eurasia, possibly because of a contrast in lithosphere strength. Weak Eurasia strained significantly during the Alpine-Himalayan collision, forcing crustal blocks to undergo significant lateral escape. The strong North American craton strained relatively little during collisional-convergent orogeny, so crustal blocks underwent relatively small displacements.
The Hills are Alive: Dynamic Ridges and Valleys in a Strike-Slip Environment
NASA Astrophysics Data System (ADS)
Duvall, A. R.; Tucker, G. E.
2014-12-01
Strike-slip fault zones have long been known for characteristic landforms such as offset and deflected rivers, linear strike-parallel valleys, and shutter ridges. Despite their common presence, questions remain about the mechanics of how these landforms arise or how their form varies as a function of slip rate, geomorphic process, or material properties. We know even less about what happens far from the fault, in drainage basin headwaters, as a result of strike-slip motion. Here we explore the effects of horizontal fault slip rate, bedrock erodibility, and hillslope diffusivity on river catchments that drain across an active strike-slip fault using the CHILD landscape evolution model. Model calculations demonstrate that lateral fault motion induces a permanent state of landscape disequilibrium brought about by fault offset-generated river lengthening alternating with abrupt shortening due to stream capture. This cycle of shifting drainage patterns and base level change continues until fault motion ceases thus creating a perpetual state of transience unique to strike-slip systems. Our models also make the surprising prediction that, in some cases, hillslope ridges oriented perpendicular to the fault migrate laterally in conjunction with fault motion. Ridge migration happens when slip rate is slow enough and/or diffusion and river incision are fast enough that the hillslopes can respond to the disequilibrium brought about by strike-slip motion. In models with faster slip rates, stronger rocks or less-diffusive hillslopes, ridge mobility is limited or arrested despite the fact that the process of river lengthening and capture continues. Fast-slip cases also develop prominent steep fault-facing hillslope facets proximal to the fault valley and along-strike topographic profiles with reduced local relief between ridges and valleys. Our results demonstrate the dynamic nature of strike-slip landscapes that vary systematically with a ratio of bedrock erodibility (K) and hillslope diffusivity (D) to the rate of horizontal advection of topography (v). These results also reveal a potential set of recognizable geomorphic signatures within strike-slip systems that should be looked to as indicators of fault activity and/or material properties.
A simple field method to identify foot strike pattern during running.
Giandolini, Marlène; Poupard, Thibaut; Gimenez, Philippe; Horvais, Nicolas; Millet, Guillaume Y; Morin, Jean-Benoît; Samozino, Pierre
2014-05-07
Identifying foot strike patterns in running is an important issue for sport clinicians, coaches and footwear industrials. Current methods allow the monitoring of either many steps in laboratory conditions or only a few steps in the field. Because measuring running biomechanics during actual practice is critical, our purpose is to validate a method aiming at identifying foot strike patterns during continuous field measurements. Based on heel and metatarsal accelerations, this method requires two uniaxial accelerometers. The time between heel and metatarsal acceleration peaks (THM) was compared to the foot strike angle in the sagittal plane (αfoot) obtained by 2D video analysis for various conditions of speed, slope, footwear, foot strike and state of fatigue. Acceleration and kinematic measurements were performed at 1000Hz and 120Hz, respectively, during 2-min treadmill running bouts. Significant correlations were observed between THM and αfoot for 14 out of 15 conditions. The overall correlation coefficient was r=0.916 (P<0.0001, n=288). The THM method is thus highly reliable for a wide range of speeds and slopes, and for all types of foot strike except for extreme forefoot strike during which the heel rarely or never strikes the ground, and for different footwears and states of fatigue. We proposed a classification based on THM: FFS<-5.49ms
NASA Astrophysics Data System (ADS)
Giambiagi, Laura; Álvarez, Patricia Pamela; Creixell, Christian; Mardonez, Diego; Murillo, Ismael; Velásquez, Ricardo; Lossada, Ana; Suriano, Julieta; Mescua, José; Barrionuevo, Matías
2017-11-01
In the High Andes of central Chile, above the flat-slab segment, analysis of more than 1,000 fault slip data from Miocene outcrops provides evidence for a change of the regional tectonic regime from compressional to strike slip. This shift in tectonic regime occurred during the waning stages of arc volcanism between 14 and 11 Ma, as a result of the shallowing of the Nazca plate, in conjunction with the migration of deformation to the Precordillera. During the early to middle Miocene, a compressive regime with horizontal σ1 axis (N86°E) was responsible for reverse slip along NNE to N-striking faults. During the late Miocene, a shift to strike-slip tectonics took place due to an increase in the absolute magnitude of the vertical stress component as the crust thickened and the gravitational potential energy increase. We argue that instead of the previously accepted highly compressional setting in the arc region during the slab flattening, the change to a strike-slip regime was the main control on mineralization. Mineralization was controlled by the promotion of fluid expulsion from the magma chambers along active, subvertical strike-slip fault systems with a high slip tendency, and focusing of fluids in localized areas undergoing extension. Under this strike-slip regime, the El Indio, Tambo, and La Despensa fault systems formed as dextral strike-slip systems. The tips and jogsites along these faults experienced local extensional stress fields, forming the El Indio and Tambo mineral districts.
28 CFR 549.63 - Initial medical evaluation and management.
Code of Federal Regulations, 2010 CFR
2010-07-01
... MANAGEMENT MEDICAL SERVICES Hunger Strikes, Inmate § 549.63 Initial medical evaluation and management. (a... hunger strike: (1) Measure and record height and weight; (2) Take and record vital signs; (3) Urinalysis... weight and vital signs at least once every 24 hours while the inmate is on a hunger strike. Other...
The 1981 direct strike lightning data. [utilizing the F-106 aircraft
NASA Technical Reports Server (NTRS)
Pitts, F. L.; Thomas, M. E.
1982-01-01
Data waveforms obtained during the 1981 direct strike lightning tests, utilizing the NASA F-106B aircraft specially instrumented for lightning electromagnetic measurements are presented. The aircraft was operated in a thunderstorm environment to elicit strikes. Electromagnetic field data were recorded for both attached lightning and free field excitation of the aircraft.
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2010-08-19
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... To Establish Strike Price Intervals and Trading Hours for Options on Index-Linked Securities April 20... establish strike-price intervals for options on Index-Linked Securities and to establish trading hours for... exchange-traded notes (``ETN'')), Phlx has proposed to establish strike price intervals and trading hours...
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..., Inc. To List Options on Trust Issued Receipts in $1 Strike Intervals July 6, 2010. Pursuant to Section... strike price intervals for options on Trust Issued Receipts. The text of the proposed rule change is... strike price intervals for options on Trust Issued Receipts (``TIRs''), including Holding Company...
Wildlife strikes to civil aircraft in the United States, 1990-2008
DOT National Transportation Integrated Search
2009-09-01
The 7,516 reported wildlife strikes to U.S. civil aircraft in 2008 brought the 19 year total of : wildlife strikes between 1990 and 2008 to 89,727. Birds (97.4%) and terrestrial mammals (2.1%) were struck 72% of the time at or below 500 feet AGL and ...
Batter's Choice: Lessons for Teaching Tactics in a Modified Striking/Fielding Game
ERIC Educational Resources Information Center
Sinclair, Christina
2004-01-01
When played in their standard form, striking/fielding games are often a favorite among elementary students; yet they allow for only limited participation, which is contradictory to quality physical education. This article presents a sequence of lessons leading to Batter's Choice, a modified striking/fielding game, designed to maximize the…
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Bird strike. 29.631 Section 29.631... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction General § 29.631 Bird strike. The... safe landing (for Category B) after impact with a 2.2-lb (1.0 kg) bird when the velocity of the...
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Bird strike. 29.631 Section 29.631... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction General § 29.631 Bird strike. The... safe landing (for Category B) after impact with a 2.2-lb (1.0 kg) bird when the velocity of the...
14 CFR 25.631 - Bird strike damage.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Bird strike damage. 25.631 Section 25.631... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction General § 25.631 Bird strike damage. The... airplane after impact with an 8-pound bird when the velocity of the airplane (relative to the bird along...
14 CFR 25.631 - Bird strike damage.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Bird strike damage. 25.631 Section 25.631... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction General § 25.631 Bird strike damage. The... airplane after impact with an 8-pound bird when the velocity of the airplane (relative to the bird along...
Expert Anticipatory Skill in Striking Sports: A Review and a Model
ERIC Educational Resources Information Center
Muller, Sean; Abernethy, Bruce
2012-01-01
Expert performers in striking sports can hit objects moving at high speed with incredible precision. Exceptionally well developed anticipation skills are necessary to cope with the severe constraints on interception. In this paper, we provide a review of the empirical evidence regarding expert interception in striking sports and propose a…
Lightning Strikes and Thunder Claps: The Strategic Bomber and Air Superiority
2012-12-01
Views November–December 2012 Air & Space Power Journal | 137 Lightning Strikes and Thunder Claps The Strategic Bomber and Air Superiority Maj Wade S...2012 to 00-00-2012 4. TITLE AND SUBTITLE Lightning Strikes and Thunder Claps: The Strategic Bomber and Air Superiority 5a. CONTRACT NUMBER 5b
NASA Astrophysics Data System (ADS)
Nam, Moon-Hyon
The term "Striking Clepsydra" is a shortened translation of the Korean name Jagyeongnu (自擊漏, tzu-chi lou in Chinese, literally "automatic-striking water-clock"). It was given to the two monumental time-keeping installations built by chief court engineer Yeong-sil Jang in AD 1432-38 under King Sejong (r. AD 1418-50) of the Joseon dynasty (1392-1910) in Seoul. These were housed separately in the Gyeongbok palace complex as major installations of the Royal Observatory Ganuidae equipped during 1432-38. One was the Striking Palace Clepsydra Borugangnu that was employed as the standard time-keeper from 1434, and the other was the Striking Heavenly Clepsydra Heumgyeonggangnu that was put into use not only as the symbol of Neo-Confucian ideology from 1438, but also as a demonstrational orrery and time-keeper. These were restored several times through the dynasty after loss by fires and warfare, and clepsydra-making technologies were succeeded by the development of armillary clocks in 1669. The National Palace Museum of Korea recreated the 1434 Striking Palace Clepsydra of King Sejong, and the replica was installed for permanent exhibition from November 2007.
Optimization of Cost of Building with Concrete Slabs Based on the Maturity Method
NASA Astrophysics Data System (ADS)
Skibicki, Szymon
2017-10-01
The maturity method is a well-known technique for determination of mechanical properties of the concrete (e.g. compressive strength) based on the development of temperature during hardening. The compressive strength of concrete can be used to determine necessary striking time of the formwork. Use of this method for this purpose is economically effective and provides necessary safety measures. This method is used in many construction sites. Time of formwork striking depends on many factors e. g. class of concrete, grade of cement, type of cement, temperature, size of the element and air humidity. The existing technical Standards and scientific research on the striking of formwork present different estimated for the striking time. Striking time for the main structural elements ranges from 14 to 21 days. For structura elements such as slabs or beams with a span of more than 6 m need to reach the minimum of 70-85% of their designed strength to remove the formwork depend on the Standards. During the construction of the buildings in summer concrete acquires the required strength for striking of the formwork faster due to the higher ambient temperature. Knowing the maturity method, we are able to estimate the compressive strength of concrete. If concrete have the required strength, the striking time can be shortened. This allows to reduce the overall costs of construction. The more concrete works are done during the construction phase the bigger the generated savings. In this article formwork striking time for concrete slabs in building based on maturity method was determined. The structure was subjected to 10 different simulated weather conditions typical for the Central and Western Europe that varied by localization of the construction. Based on simulated weather conditions the temperature in structural elements was established. The results allowed to determine the formwork striking time using the maturity method. Presented analysis shows that use of the maturity method on construction site can result in lower overall costs due to shorter time of constructing.
Physicians' strikes and the competing bases of physicians' moral obligations.
MacDougall, D Robert
2013-09-01
Many authors have addressed the morality of physicians' strikes on the assumption that medical practice is morally different from other kinds of occupations. This article analyzes three prominent theoretical accounts that attempt to ground such special moral obligations for physicians--practice-based accounts, utilitarian accounts, and social contract accounts--and assesses their applicability to the problem of the morality of strikes. After critiquing these views, it offers a fourth view grounding special moral obligations in voluntary commitments, and explains why this is a preferable basis for understanding physicians' moral obligations in general and especially as pertaining to strikes.
NASA Astrophysics Data System (ADS)
Burkhard, L. M.; Cameron, M. E.; Smith-Konter, B. R.; Seifert, F.; Pappalardo, R. T.; Collins, G. C.
2015-12-01
Ganymede's fractured surface reveals many large-scale, morphologically distinct regions of inferred distributed shear and strike-slip faulting that may be important to the structural development of its surface and in the transition from dark to light (grooved) materials. To better understand the role of strike-slip tectonism in shaping Ganymede's complex icy surface, we perform a detailed mapping of key examples of strike-slip morphologies (i.e., en echelon structures, strike-slip duplexes, laterally offset pre-existing features, and possible strained craters) from Galileo and Voyager images. We focus on complex structures associated with grooved terrain (e.g. Nun Sulcus, Dardanus Sulcus, Tiamat Sulcus, and Arbela Sulcus) and terrains transitional from dark to light terrain (e.g. the boundary between Nippur Sulcus and Marius Regio, including Byblus Sulcus and Philus Sulcus). Detailed structural interpretations suggest strong evidence of strike-slip faulting in some regions (i.e., Nun and Dardanus Sulcus); however, further investigation of additional strike-slip structures is required of less convincing regions (i.e., Byblus Sulcus). Where applicable, these results are synthesized into a global database representing an inferred sense of shear for many of Ganymede's fractures. Moreover, when combined with existing observations of extensional features, these results help to narrow down the range of possible principal stress directions that could have acted at the regional or global scale to produce grooved terrain on Ganymede.
Foot strike patterns and collision forces in habitually barefoot versus shod runners.
Lieberman, Daniel E; Venkadesan, Madhusudhan; Werbel, William A; Daoud, Adam I; D'Andrea, Susan; Davis, Irene S; Mang'eni, Robert Ojiambo; Pitsiladis, Yannis
2010-01-28
Humans have engaged in endurance running for millions of years, but the modern running shoe was not invented until the 1970s. For most of human evolutionary history, runners were either barefoot or wore minimal footwear such as sandals or moccasins with smaller heels and little cushioning relative to modern running shoes. We wondered how runners coped with the impact caused by the foot colliding with the ground before the invention of the modern shoe. Here we show that habitually barefoot endurance runners often land on the fore-foot (fore-foot strike) before bringing down the heel, but they sometimes land with a flat foot (mid-foot strike) or, less often, on the heel (rear-foot strike). In contrast, habitually shod runners mostly rear-foot strike, facilitated by the elevated and cushioned heel of the modern running shoe. Kinematic and kinetic analyses show that even on hard surfaces, barefoot runners who fore-foot strike generate smaller collision forces than shod rear-foot strikers. This difference results primarily from a more plantarflexed foot at landing and more ankle compliance during impact, decreasing the effective mass of the body that collides with the ground. Fore-foot- and mid-foot-strike gaits were probably more common when humans ran barefoot or in minimal shoes, and may protect the feet and lower limbs from some of the impact-related injuries now experienced by a high percentage of runners.
Wei, Lai; Lei, Huai-Cheng; Yu, Xiao-Jun; Lai, Xiao-Ping; Qian, Hong; Xu, Xiao-Hu; Zhu, Fang-Cheng
2013-04-01
By observing the cerebral beta-amyloid precursor protein (beta-APP) expression in the chronic alcoholism rats with slight cerebral injury, to discuss the correlation of chronic alcoholism and death caused by traumatic subarachnoid haemorrhage (TSAH). Sixty male SD rats were randomly divided into watering group, watering group with strike, alcoholism group and alcoholism group with strike. Among them, the alcohol was used for continuous 4 weeks in alcoholism groups and the concussion was made in groups with strike. In each group, HE staining and immunohistochemical staining of the cerebral tissues were done and the results were analyzed by the histopathologic image system. In watering group, there was no abnormal. In watering group with strike, mild neuronic congestion was found. In alcoholism group, vascular texture on cerebral surface was found. And the neurons arranged in disorder with dilated intercellular space. In alcoholism group with strike, diffuse congestion on cerebral surface was found. And there was TSAH with thick-layer patches around brainstem following irregular axonotmesis. The quantity of beta-APP IOD in alcoholism group was significantly higher in the frontal lobe, hippocampus, cerebellum, brainstem than those in watering group with strike and alcoholism group with strike. The cerebral tissues with chronic alcoholism, due to the decreasing tolerance, could cause fatal TSAH and pathological changes in cerebral tissues of rats under slight cerebral injury.
Correlates of avian building strikes at a glass façade museum surrounded by avian habitat
NASA Astrophysics Data System (ADS)
Kahle, L.; Flannery, M.; Dumbacher, J. P.
2013-12-01
Bird window collisions are the second largest anthropogenic cause of bird deaths in the world. Effective mitigation requires an understanding of which birds are most likely to strike, when, and why. Here, we examine five years of avian window strike data from the California Academy of Sciences - a relatively new museum with significant glass façade situated in Golden Gate Park, San Francisco. We examine correlates of window-killed birds, including age, sex, season, and migratory or sedentary tendencies of the birds. We also examine correlates of window kills such as presence of habitat surrounding the building and overall window area. We found that males are almost three times more likely than females to mortally strike windows, and immature birds are three times more abundant than adults in our window kill dataset. Among seasons, strikes were not notably different in spring, summer, and fall; however they were notably reduced in winter. There was no statistical effect of building orientation (north, south, east, or west), and the presence of avian habitat directly adjacent to windows had a minor effect. We also report ongoing studies examining various efforts to reduce window kill (primarily external decals and large electronic window blinds.) We hope that improving our understanding of the causes of the window strikes will help us strategically reduce window strikes.
"To the Ragged Edge of Anarchy": The 1894 Pullman Boycott.
ERIC Educational Resources Information Center
Schneirov, Richard
1999-01-01
Highlights the events of the 1894 Pullman strike and boycott that pitted the American Railway Union against the combined forces of the federal government, railroad companies, and the Pullman Sleeping Car Company. States that the Pullman strike was a devastating setback for industrial unionism, but is the most well-known of all U.S. strikes. (CMK)
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2010-10-26
... would allow the Exchange to offer investors additional opportunities to use the $0.50 Strike Program... Interpretation and Policy .01 to Rule 5.5 to expand the $0.50 Strike Program in order to provide investors with... strike offerings to market participants, such as traders and retail investors, and thereby enhance their...
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2011-01-12
... reciprocity currently is permitted with the Exchange's $1 Strike Program, $.50 Strike Program and $2.50 Strike... interest because the proposed reciprocity provision is similar to reciprocity provisions in place for other... reciprocity provision). \\11\\ For purposes only of waiving the 30-day operative delay, the Commission has...
Reporting the Great Railroad Strike: How Ideology Shaped the News.
ERIC Educational Resources Information Center
Coward, John
The Great Railroad Strike of 1877, a national catastrophe and the major news story of the year, was the first national labor strike in U.S. history. Because of the ideological bias of the press, specifically its implicit commitment to capitalism and to objectivity (itself a "myth" of social order), newspapers of the period could be…
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2010-05-17
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2010-03-22
... to handle the additional traffic associated with the listing and trading of $1 strikes where the...-Regulatory Organizations; NASDAQ OMX PHLX, Inc.; Notice of Filing of Proposed Rule Change To Establish Strike... 1012 (Series of Options Open for Trading) to establish strike-price intervals for options on Index...
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... LLC To List Options on Trust Issued Receipts in $1 Strike Intervals July 6, 2010. Pursuant to section... strike price intervals for options on Trust Issued Receipts. The text of the proposed rule change is... establish strike price intervals for options on Trust Issued Receipts (``TIRs''), including Holding Company...
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... necessary systems capacity to handle the additional traffic associated with the expanded range of strike... Effectiveness of Proposed Rule Change To Expand the Range of Strike Price Intervals for VIX Options October 21... amend Rule 24.9.01(e), Terms of Index Option Contracts, to expand the range of strike price intervals...
Picket Fencing: Amid Fewer Strikes, Some See Waning Sympathy for Educators
ERIC Educational Resources Information Center
Sack, Joetta L.
2006-01-01
Once as familiar in the back-to-school ritual as falling leaves, teacher strikes seem headed for a winter freeze. According to the nation's largest teacher's union, about 15 of the National Education Association's (NEA) 14,000 local affiliates have gone on strike since the start of this school year. In Pennsylvania--a traditional union…
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2011-09-28
... underlying price ($24.50) is $20, the Exchange may list a $22 strike. The proposal also contains certain non... Rule to Simplify the $1 Strike Price Interval Program September 22, 2011. I. Introduction On July 26... amend Interpretation and Policy .01 to Rule 5.5 to simplify the $1 Strike Price Interval Program (the...
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2012-10-25
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2012-02-07
... SLV and USO strike price intervals. \\4\\ The Exchange also proposed certain non-substantive changes to... Strike Price Intervals for SLV and USO Options February 1, 2012. I. Introduction On December 7, 2011...-4 thereunder,\\2\\ a proposed rule change regarding strike price intervals for options on iShares[reg...
ERIC Educational Resources Information Center
Deacon, H. J.
2014-01-01
While the South African Constitution enshrines both children's right to a basic education and teachers' right to strike, conflict between these two often occurs when the way in which teachers' unions conduct strike actions detracts from learners' education. This article identifies the parties affected by industrial action in the school context,…
Barnhart, William; Briggs, Richard; Reitman, Nadine G.; Gold, Ryan D.; Hayes, Gavin
2015-01-01
Deformation is commonly accommodated by strain partitioning on multiple, independent strike-slip and dip-slip faults in continental settings of oblique plate convergence. As a corollary, individual faults tend to exhibit one sense of slip – normal, reverse, or strike-slip – until whole-scale changes in boundary conditions reactivate preexisting faults in a new deformation regime. In this study, we show that a single continental fault may instead partition oblique strain by alternatively slipping in a strike-slip or a dip-slip sense during independent fault slip events. We use 0.5 m resolution optical imagery and sub-pixel correlation analysis of the 200+ km 200+km"> 2013 Mw7.7 Balochistan, Pakistan earthquake to document co-seismic surface slip characteristics and Quaternary tectonic geomorphology along the causative Hoshab fault. We find that the 2013 earthquake, which involved a ∼6:1 strike-slip to dip-slip ratio, ruptured a structurally segmented fault. Quaternary geomorphic indicators of gross fault-zone morphology reveal both reverse-slip and strike-slip deformation in the rupture area of the 2013 earthquake that varies systematically along fault strike despite nearly pure strike-slip motion in 2013. Observations of along-strike variations in range front relief and geomorphic offsets suggest that the Hoshab fault accommodates a substantial reverse component of fault slip in the Quaternary, especially along the southern section of the 2013 rupture. We surmise that Quaternary bimodal slip along the Hoshab fault is promoted by a combination of the arcuate geometry of the Hoshab fault, the frictional weakness of the Makran accretionary prism, and time variable loading conditions from adjacent earthquakes and plate interactions.
NASA Astrophysics Data System (ADS)
Zhao, H.; Wu, L.; Xiao, A.
2016-12-01
We present a detailed structural analysis on the fault geometry and Cenozoic development in the Dongping area, northwestern Qaidam Basin, based on the precise 3-D seismic interpretation, remote sensing images and seismic attribute analysis. Two conflicting fault systems distributed in different orientations ( EW-striking and NNW-striking) with opposing senses of shear are recognized and discussed, and the interaction between them provides new insights to the intracontinental deformation of the Qaidam Basin within the NE Tibetan Plateau. The EW-striking fault system constitutes the south part of the Altyn left-slip positive flower structure. Faulting on the EW-striking faults dominated the northwestern Qaidam since 40 Ma in respond to the inception of the Altyn Tagh fault system as a ductile shear zone, tilting the south slope of the Altyn Tagh. Whereas the NNW-striking fault system became the dominant structures since the mid-Miocene ( 15 Ma), induced by the large scale strike-slip of the Altyn Tagh fault which leads to the NE-SW directed compression of the Qaidam Basin. Thus it evidently implies a structural conversion taking place within the NE Tibetan Plateau since the mid-Miocece ( 15 Ma). Interestingly, the preexisting faults possibly restrained the development of the later period faults, while the latter tended to track and link to the former fault traces. Taken the large scale sinistral striking-slip East Kunlun fault system into account, the late Cenozoic intracontinental deformation in the Qaidam Basin showing the dextral transpressional attribute is suggested to be the consequence of the combined effect of its two border sinistral strike-slip faults, which furthermore favors a continuous and lateral-extrusion mechanism of the growth of the NE Tibetan Plateau.
Strain accumulation and rotation in the Eastern California Shear Zone
Savage, J.C.; Gan, Weijun; Svarc, J.L.
2001-01-01
Although the Eastern California Shear Zone (ECSZ) (strike ???N25??W) does not quite coincide with a small circle drawn about the Pacific-North America pole of rotation, trilateration and GPS measurements demonstrate that the motion within the zone corresponds to right-lateral simple shear across a vertical plane (strike N33??W??5??) roughly parallel to the tangent to that local small circle (strike ???N40??W). If the simple shear is released by slip on faults subparallel to the shear zone, the accumulated rotation is also released, leaving no secular rotation. South of the Garlock fault the principal faults (e.g., Calico-Blackwater fault) strike ???N40??W, close enough to the strike of the vertical plane across which maximum right-lateral shear accumulates to almost wholly accommodate that accumulation of both strain and rotation by right-lateral slip. North of the Garlock fault dip slip as well as strike slip on the principal faults (strike ???N20??W) is required to accommodate the simple shear accumulation. In both cases the accumulated rotation is released with the shear strain. The Garlock fault, which transects the ECSZ, is not offset by north-northwest striking faults nor, despite geological evidence for long-term left-lateral slip, does it appear at the present time to be accumulating left-lateral simple shear strain across the fault due to slip at depth. Rather the motion is explained by right-lateral simple shear across the orthogonal ECSZ. Left-lateral slip on the Garlock fault will release the shear strain accumulating there but would augment the accumulating rotation, resulting in a secular clockwise rotation rate ???80 nrad yr-1 (4.6?? Myr-1).
NASA Astrophysics Data System (ADS)
Barnhart, W. D.; Briggs, R. W.; Reitman, N. G.; Gold, R. D.; Hayes, G. P.
2015-06-01
Deformation is commonly accommodated by strain partitioning on multiple, independent strike-slip and dip-slip faults in continental settings of oblique plate convergence. As a corollary, individual faults tend to exhibit one sense of slip - normal, reverse, or strike-slip - until whole-scale changes in boundary conditions reactivate preexisting faults in a new deformation regime. In this study, we show that a single continental fault may instead partition oblique strain by alternatively slipping in a strike-slip or a dip-slip sense during independent fault slip events. We use 0.5 m resolution optical imagery and sub-pixel correlation analysis of the 200 + km 2013 Mw7.7 Balochistan, Pakistan earthquake to document co-seismic surface slip characteristics and Quaternary tectonic geomorphology along the causative Hoshab fault. We find that the 2013 earthquake, which involved a ∼6:1 strike-slip to dip-slip ratio, ruptured a structurally segmented fault. Quaternary geomorphic indicators of gross fault-zone morphology reveal both reverse-slip and strike-slip deformation in the rupture area of the 2013 earthquake that varies systematically along fault strike despite nearly pure strike-slip motion in 2013. Observations of along-strike variations in range front relief and geomorphic offsets suggest that the Hoshab fault accommodates a substantial reverse component of fault slip in the Quaternary, especially along the southern section of the 2013 rupture. We surmise that Quaternary bimodal slip along the Hoshab fault is promoted by a combination of the arcuate geometry of the Hoshab fault, the frictional weakness of the Makran accretionary prism, and time variable loading conditions from adjacent earthquakes and plate interactions.
Tetreault, J.; Jones, C.H.; Erslev, E.; Larson, S.; Hudson, M.; Holdaway, S.
2008-01-01
Significant fold-axis-parallel slip is accommodated in the folded strata of the Grayback monocline, northeastern Front Range, Colorado, without visible large strike-slip displacement on the fold surface. In many cases, oblique-slip deformation is partitioned; fold-axis-normal slip is accommodated within folds, and fold-axis-parallel slip is resolved onto adjacent strike-slip faults. Unlike partitioning strike-parallel slip onto adjacent strike-slip faults, fold-axis-parallel slip has deformed the forelimb of the Grayback monocline. Mean compressive paleostress orientations in the forelimb are deflected 15??-37?? clockwise from the regional paleostress orientation of the northeastern Front Range. Paleomagnetic directions from the Permian Ingleside Formation in the forelimb are rotated 16??-42?? clockwise about a bedding-normal axis relative to the North American Permian reference direction. The paleostress and paleomagnetic rotations increase with the bedding dip angle and decrease along strike toward the fold tip. These measurements allow for 50-120 m of fold-axis-parallel slip within the forelimb, depending on the kinematics of strike-slip shear. This resolved horizontal slip is nearly equal in magnitude to the ???180 m vertical throw across the fold. For 200 m of oblique-slip displacement (120 m of strike slip and 180 m of reverse slip), the true shortening direction across the fold is N90??E, indistinguishable from the regionally inferred direction of N90??E and quite different from the S53??E fold-normal direction. Recognition of this deformational style means that significant amounts of strike slip can be accommodated within folds without axis-parallel surficial faulting. ?? 2008 Geological Society of America.
Muula, A S; Phiri, A
2003-03-01
Health workers and support staff at Malawi's major referral hospital, the Queen Elizabeth Central Hospital, Blantyre, were on strike between 5th and 19th October 2001. The health workers' grievances included: lack of risk allowances; poor professional allowances; low salaries; and low housing allowances. The strike resulted in almost total closure of the 1500-bed hospital; only the burns and orthopaedic wards continued to serve patients. Volunteer staff, comprising the Red Cross, and nursing and medical students provided services. Verbal and written threats by the authorities had minimal effect on terminating the strike; rather, they encouraged the resolve to continue with the industrial action. We report aspects of the genesis, progress and resolution of the strike. Although not much seems to have been achieved, both the employer and the workers need to draw lessons from the experience.
Soldatini, Cecilia; Albores-Barajas, Yuri Vladimir; Lovato, Tomas; Andreon, Adriano; Torricelli, Patrizia; Montemaggiori, Alessandro; Corsa, Cosimo; Georgalas, Vyron
2011-01-01
The presence of wildlife in airport areas poses substantial hazards to aviation. Wildlife aircraft collisions (hereafter wildlife strikes) cause losses in terms of human lives and direct monetary losses for the aviation industry. In recent years, wildlife strikes have increased in parallel with air traffic increase and species habituation to anthropic areas. In this paper, we used an ecological approach to wildlife strike risk assessment to eight Italian international airports. The main achievement is a site-specific analysis that avoids flattening wildlife strike events on a large scale while maintaining comparable airport risk assessments. This second version of the Birdstrike Risk Index (BRI2) is a sensitive tool that provides different time scale results allowing appropriate management planning. The methodology applied has been developed in accordance with the Italian Civil Aviation Authority, which recognizes it as a national standard implemented in the advisory circular ENAC APT-01B.
Recognition on space photographs of structural elements of Baja California
NASA Technical Reports Server (NTRS)
Hamilton, W.
1971-01-01
Gemini and Apollo photographs provide illustrations of known structural features of the peninsula and some structures not recognized previously. An apparent transform relationship between strike-slip and normal faulting is illustrated by the overlapping vertical photographs of northern Baja California. The active Agua Blanca right-lateral strike-slip fault trends east-southeastward to end at the north end of the Valle San Felipe and Valle Chico. The uplands of the high Sierra San Pedro Martir are a low-relief surface deformed by young faults, monoclines, and warps, which mostly produce west-facing steps and slopes; the topography is basically structural. The Sierra Cucapas of northeasternmost Baja California and the Colorado River delta of northwesternmost Sonora are broken by northwest-trending strike-slip faults. A strike-slip fault is inferred to trend northward obliquely from near Cabo San Lucas to La Paz, thence offshore until it comes ashore again as the Bahia Concepcion strike-slip fault.
Soldatini, Cecilia; Albores-Barajas, Yuri Vladimir; Lovato, Tomas; Andreon, Adriano; Torricelli, Patrizia; Montemaggiori, Alessandro; Corsa, Cosimo; Georgalas, Vyron
2011-01-01
The presence of wildlife in airport areas poses substantial hazards to aviation. Wildlife aircraft collisions (hereafter wildlife strikes) cause losses in terms of human lives and direct monetary losses for the aviation industry. In recent years, wildlife strikes have increased in parallel with air traffic increase and species habituation to anthropic areas. In this paper, we used an ecological approach to wildlife strike risk assessment to eight Italian international airports. The main achievement is a site-specific analysis that avoids flattening wildlife strike events on a large scale while maintaining comparable airport risk assessments. This second version of the Birdstrike Risk Index (BRI2) is a sensitive tool that provides different time scale results allowing appropriate management planning. The methodology applied has been developed in accordance with the Italian Civil Aviation Authority, which recognizes it as a national standard implemented in the advisory circular ENAC APT-01B. PMID:22194950
Measurements of lightning rod responses to nearby strikes
NASA Astrophysics Data System (ADS)
Moore, C. B.; Aulich, G. D.; Rison, W.
2000-05-01
Following Benjamin Franklin's invention of the lightning rod, based on his discovery that electrified objects could be discharged by approaching them with a metal needle in hand, conventional lightning rods in the U.S. have had sharp tips. In recent years, the role of the sharp tip in causing a lightning rod to act as a strike receptor has been questioned leading to experiments in which pairs of various sharp-tipped and blunt rods have been exposed beneath thunderclouds to determine the better strike receptor. After seven years of tests, none of the sharp Franklin rods or of the so-called “early streamer emitters” has been struck, but 12 blunt rods with tip diameters ranging from 12.7 mm to 25.4 mm have taken strikes. Our field experiments and our analyses indicate that the strike-reception probabilities of Franklin's rods are greatly increased when their tips are made moderately blunt.
Strike one! Aluminum. Strike two! Maple. Will EAB be strike three?
Brian Boltz; Jan Wiedenbeck
2010-01-01
Baseball bats made out of white ash (Fraxinus americana L.) have been the standard for professional baseball since the beginning of the game in 1849. Until the mid- to late-1970s, ash was the principal material used for all baseball (and softball) bats -- major league, minor league, adult, and youth. The market share of baseball bats made from wood...
Final Environmental Assessment for Conventional Strike Missile Demonstration
2010-08-11
impacts of conducting a single demonstration flight test of the Conventional Strike Missile (CSM). The CSM Demonstration flight test vehicle would...Vehicle would glide at hypersonic velocities in the upper atmosphere, prior to a land or ocean impact at the US Army Kwajalein Atoll/Reagan Test Site...SIGNIFICANT IMPACT ENVIRONMENTAL ASSESSMENT FOR CONVENTIONAL STRIKE MISSILE DEMONSTRATION AGENCY: United States Air Force (USAF) BACKGROUND
Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-09
... stocks on which option series may be listed at $1 strike price intervals. To be eligible for inclusion in..., 2003) (SR-Phlx-2002-55) (approval of pilot program). The Strike Program was then extended several times... option series with $1 strike price intervals for any class selected for the program, except as...
20 CFR 655.733 - What is the third LCA requirement, regarding strikes and lockouts?
Code of Federal Regulations, 2010 CFR
2010-04-01
... lockouts? An employer seeking to employ H-1B nonimmigrants shall state on Form ETA 9035 or 9035E that there... of the strike or lockout, shall submit to ETA, by U.S. mail, facsimile (FAX), or private carrier... occupational classification at such place of employment until ETA determines that the strike or lockout has...
Labor Conflict on the National Stage: Metaphoric Lenses in Israel's Teachers' Strike
ERIC Educational Resources Information Center
Shenkar, Miriam; Shenkar, Oded
2011-01-01
Teachers often embed their labor demands within a broader context to claim high moral ground and build community support. We analyze a recent teachers' strike in Israel, looking at how the strike played out in a country where the challenges of globalization collided with a socialist legacy in the face of an existential threat. The analysis reveals…
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2010-09-09
... Permit Concurrent Listing of $2.50 and $1 Strikes on MNX Options September 2, 2010. Pursuant to Section... concurrently list $2.50 and $1 strikes on Mini- Nasdaq-100 Index (``MNX'') options, and that certain listing parameters only apply to $1 strikes on MNX options. The text of the proposed rule change is available from...
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2010-06-21
... Stock Market LLC To List Options on Trust Issued Receipts in $1 Strike Intervals June 15, 2010. Pursuant... options on Trust Issued Receipts in $1 strike price intervals. The text of the proposed rule change is...''), as defined in Supplementary Material to Section 6 at .01(b), in $1 or greater strike price intervals...
Teaching Striking Skills in Elementary Physical Education Using Woodball
ERIC Educational Resources Information Center
Chang, Seung Ho; Lee, Jihyun
2017-01-01
Object control (OC) skills are a part of fundamental motor skills and basic functional skills, which work as a prerequisite to becoming a skilled performer in many sports. Of various OC skills, striking is one of the most difficult to master due to a variety of interrelated movement components. A form of vertical or underarm striking is a more…
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2011-08-09
... the $1 Strike Price Interval Program August 4, 2011. Pursuant to Section 19(b)(1) of the Securities... Proposed Rule Change CBOE proposes to amend its rules in order to simplify the $1 Strike Price Interval... Policy .01 to Rule 5.5 in order to simplify the $1 Strike Price Interval Program (``Program''). In 2003...
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2011-02-01
... Listing of Options Series with $1 Strike Prices January 25, 2011. I. Introduction On November 24, 2010... Strike Price Program. The proposed rule change was published for comment in the Federal Register on... proposed to amend Rule 6.4 Commentary .04 to modify the operation of the $1 Strike Price Program. Currently...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-04
... Amending Commentary .06 to Rule 903 in Order To Simplify the $1 Strike Price Program September 28, 2011... to Rule 903 in order to simplify the $1 Strike Price Program. The text of the proposed rule change is... order to simplify the $1 Strike Price Program (``Program''). In 2003, the Commission issued an order...
Lightning Strike in Pregnancy With Fetal Injury.
Galster, Kellen; Hodnick, Ryan; Berkeley, Ross P
2016-06-01
Injuries from lightning strikes are an infrequent occurrence, and are only rarely noted to involve pregnant victims. Only 13 cases of lightning strike in pregnancy have been previously described in the medical literature, along with 7 additional cases discovered within news media reports. This case report presents a novel case of lightning-associated injury in a patient in the third trimester of pregnancy, resulting in fetal ischemic brain injury and long-term morbidity, and reviews the mechanics of lightning strikes along with common injury patterns of which emergency providers should be aware. Copyright © 2016 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.
System and Method of Locating Lightning Strikes
NASA Technical Reports Server (NTRS)
Medelius, Pedro J. (Inventor); Starr, Stanley O. (Inventor)
2002-01-01
A system and method of determining locations of lightning strikes has been described. The system includes multiple receivers located around an area of interest, such as a space center or airport. Each receiver monitors both sound and electric fields. The detection of an electric field pulse and a sound wave are used to calculate an area around each receiver in which the lighting is detected. A processor is coupled to the receivers to accurately determine the location of the lighting strike. The processor can manipulate the receiver data to compensate for environmental variables such as wind, temperature, and humidity. Further, each receiver processor can discriminate between distant and local lightning strikes.
Civil helicopter wire strike assessment study. Volume 1: Findings and recommendations
NASA Technical Reports Server (NTRS)
Tuomela, C. H.; Brennan, M. F.
1980-01-01
Approximately 208 civil helicopter wire strike accidents for a ten year period 1970 to 1979 are analyzed. It is found that 83% of the wire strikes occurred during bright clear weather. Analysis of the accidents is organized under pilot, environment, and machine factors. Methods to reduce the wire strike accident rate are discussed, including detection/warning devices, identification of wire locations prior to flight, wire cutting devices, and implementation of training programs. The benefits to be gained by implementing accident avoidance methods are estimated to be fully justified by reduction in injury and death and reduction of aircraft damage and loss.
Hunger strike among detainees: guidance for good medical practice.
Gétaz, Laurent; Rieder, Jean-Pierre; Nyffenegger, Laurent; Eytan, Ariel; Gaspoz, Jean-Michel; Wolff, Hans
2012-09-17
Hunger strike is a regularly reported problem in prison. Although clinical situations are rarely severe, hospitalisation is often considered. In consequence, it is not only physicians working in prisons, but also hospital medical teams who face challenges related to hunger strike, involving somatic, psychological, legal and human rights aspects. Furthermore, deontological rules must be strictly respected when delivering care, particularly in prison setting. Starvation involves metabolic changes and can cause severe, and sometimes even irreversible or fatal complications. Moreover, the phase of re-alimentation should not be trivialised, as re-feeding syndrome is a potentially fatal phenomenon. This article provides guidance for monitoring and management of patients on hunger strike.
Fuller, Daniel; Sahlqvist, Shannon; Cummins, Steven; Ogilvie, David
2012-01-01
To investigate the immediate and sustained effects of two London Underground strikes on use of a public bicycle share program. An interrupted time series design was used to examine the impact of two 24 hour strikes on the total number of trips per day and mean trip duration per day on the London public bicycle share program. The strikes occurred on September 6th and October 4th 2010 and limited service on the London Underground. The mean total number of trips per day over the whole study period was 14,699 (SD=5390) while the mean trip duration was 18.5 minutes (SD=3.7). Significant increases in daily trip count were observed following strike 1 (3864: 95% CI 125 to 7604) and strike 2 (11,293: 95% CI 5169 to 17,416). Events that greatly constrain the primary motorised mode of transportation for a population may have unintended short-term effects on travel behaviour. These findings suggest that limiting transportation options may have the potential to increase population levels of physical activity by promoting the use of cycling. Copyright © 2011 Elsevier Inc. All rights reserved.
NASA Technical Reports Server (NTRS)
Fisher, B. D.; Plumer, J. A.
1984-01-01
The direct lightning strike data and associated flight conditions recorded from 1980 to 1983 during 742 thunderstorm penetrations with a NASA F-106B in Oklahoma and Virginia are studied with an emphasis on aircraft protection design. The individual lightning attachment spots were plotted on isometric projections of the aircraft to identify lightning entry and exit points and swept flash patterns. The altitudes, ambient temperatures, turbulence, and precipitation at which the strikes occurred are summarized and discussed. It was noted that peak strike rates (0.81 strikes/min and 3 strikes/penetration) occurred at altitudes between 11 km and 11.6 km corresponding to ambient temperatures between -40 C and -45 C. The data confirmed that initial entry and exit points most frequently occur at aircraft extremities, in this case the nose boom, the wing tips, the vertical fin cap, and the afterburner. The swept-flash attachment paths and burn marks found in this program indicate that the mid-span areas of swept aircraft may be more susceptible to lightning than previously thought. It was also found that lightning strikes may attach to spots within the engine tail pipe.
Isolated Sensorineural Hearing Loss as a Sequela after Lightning Strike
Turan, Mahfuz; Kalkan, Ferhat; Bozan, Nazım; Özçalimli, İsa; Zeki Erdem, Mehmet; Yalınkılıç, Abdülaziz; Garca, Mehmet Fatih
2015-01-01
In most of the surviving patients after a lightning strike, audiovestibular abnormalities have been reported. The most frequently reported type of abnormalities is a tympanic membrane perforation with hearing loss and external ear canal burn. However a sensor neural hearing loss and mixed type hearing loss can also occur, but these occur rarely. A nineteen-year-old female patient had, after a lightning strike, serious burns on the left ear, behind the ear, and on the chest and neck. She also had in her left ear 108 dB hearing loss with irregular central perforation and in her right ear 52 dB sensorineural hearing loss. There was no hearing loss before the strike. A hearing aid was recommended for the right ear and good care and follow-up were recommended for the left ear. A lightning strike can cause serious audiological damage. Therefore, it is necessary to make a careful audiovestibular evaluation of the patients. Although there exist rarely healed cases from sensorineural hearing loss after lightning strike in literature, in our case hearing loss occurred bilaterally and then it healed unilaterally. This condition is quite rare in literature. PMID:26161278
NASA Astrophysics Data System (ADS)
Koyi, Hemin; Nilfouroushan, Faramarz; Hessami, Khaled
2015-04-01
A series of scaled analogue models are run to study the degree of coupling between basement block kinematics and cover deformation. In these models, rigid basal blocks were rotated about vertical axis in a "bookshelf" fashion, which caused strike-slip faulting along the blocks and, to some degrees, in the overlying cover units of loose sand. Three different combinations of cover basement deformations are modeled; cover shortening prior to basement fault movement; basement fault movement prior to shortening of cover units; and simultaneous cover shortening with basement fault movement. Model results show that the effect of basement strike-slip faults depends on the timing of their reactivation during the orogenic process. Pre- and syn-orogen basement strike-slip faults have a significant impact on the structural pattern of the cover units, whereas post-orogenic basement strike-slip faults have less influence on the thickened hinterland of the overlying fold-and-thrust belt. The interaction of basement faulting and cover shortening results in formation of rhomb features. In models with pre- and syn-orogen basement strike-slip faults, rhomb-shaped cover blocks develop as a result of shortening of the overlying cover during basement strike-slip faulting. These rhombic blocks, which have resemblance to flower structures, differ in kinematics, genesis and structural extent. They are bounded by strike-slip faults on two opposite sides and thrusts on the other two sides. In the models, rhomb-shaped cover blocks develop as a result of shortening of the overlying cover during basement strke-slip faulting. Such rhomb features are recognized in the Alborz and Zagros fold-and-thrust belts where cover units are shortened simultaneously with strike-slip faulting in the basement. Model results are also compared with geodetic results obtained from combination of all available GPS velocities in the Zagros and Alborz FTBs. Geodetic results indicate domains of clockwise and anticlockwise rotation in these two FTBs. The typical pattern of structures and their spatial distributions are used to suggest clockwise block rotation of basement blocks about vertical axes and their associated strike-slip faulting in both west-central Alborz and the southeastern part of the Zagros fold-and-thrust belt.
Select injury-related variables are affected by stride length and foot strike style during running.
Boyer, Elizabeth R; Derrick, Timothy R
2015-09-01
Some frontal plane and transverse plane variables have been associated with running injury, but it is not known if they differ with foot strike style or as stride length is shortened. To identify if step width, iliotibial band strain and strain rate, positive and negative free moment, pelvic drop, hip adduction, knee internal rotation, and rearfoot eversion differ between habitual rearfoot and habitual mid-/forefoot strikers when running with both a rearfoot strike (RFS) and a mid-/forefoot strike (FFS) at 3 stride lengths. Controlled laboratory study. A total of 42 healthy runners (21 habitual rearfoot, 21 habitual mid-/forefoot) ran overground at 3.35 m/s with both a RFS and a FFS at their preferred stride lengths and 5% and 10% shorter. Variables did not differ between habitual groups. Step width was 1.5 cm narrower for FFS, widening to 0.8 cm as stride length shortened. Iliotibial band strain and strain rate did not differ between foot strikes but decreased as stride length shortened (0.3% and 1.8%/s, respectively). Pelvic drop was reduced 0.7° for FFS compared with RFS, and both pelvic drop and hip adduction decreased as stride length shortened (0.8° and 1.5°, respectively). Peak knee internal rotation was not affected by foot strike or stride length. Peak rearfoot eversion was not different between foot strikes but decreased 0.6° as stride length shortened. Peak positive free moment (normalized to body weight [BW] and height [h]) was not affected by foot strike or stride length. Peak negative free moment was -0.0038 BW·m/h greater for FFS and decreased -0.0004 BW·m/h as stride length shortened. The small decreases in most variables as stride length shortened were likely associated with the concomitant wider step width. RFS had slightly greater pelvic drop, while FFS had slightly narrower step width and greater negative free moment. Shortening one's stride length may decrease or at least not increase propensity for running injuries based on the variables that we measured. One foot strike style does not appear universally better than the other; rather, different foot strike styles may predispose runners to different types of injuries. © 2015 The Author(s).
ten Brink, Uri S.; Lin, J.
2004-01-01
Strike-slip faults in the forearc region of a subduction zone often present significant seismic hazard because of their proximity to population centers. We explore the interaction between thrust events on the subduction interface and strike-slip faults within the forearc region using three-dimensional models of static Coulomb stress change. Model results reveal that subduction earthquakes with slip vectors subparallel to the trench axis enhance the Coulomb stress on strike-slip faults adjacent to the trench but reduce the stress on faults farther back in the forearc region. In contrast, subduction events with slip vectors perpendicular to the trench axis enhance the Coulomb stress on strike-slip faults farther back in the forearc, while reducing the stress adjacent to the trench. A significant contribution to Coulomb stress increase on strike-slip faults in the back region of the forearc comes from "unclamping" of the fault, i.e., reduction in normal stress due to thrust motion on the subduction interface. We argue that although Coulomb stress changes from individual subduction earthquakes are ephemeral, their cumulative effects on the pattern of lithosphere deformation in the forearc region are significant. We use the Coulomb stress models to explain the contrasting deformation pattern between two adjacent segments of the Caribbean subduction zone. Subduction earthquakes with slip vectors nearly perpendicular to the Caribbean trench axis is dominant in the Hispaniola segment, where the strike-slip faults are more than 60 km inland from the trench. In contrast, subduction slip motion is nearly parallel to the Caribbean trench axis along the Puerto Rico segment, where the strike-slip fault is less than 15 km from the trench. This observed jump from a strike-slip fault close to the trench axis in the Puerto Rico segment to the inland faults in Hispaniola is explained by different distributions of Coulomb stress in the forearc region of the two segments, as a result of the change from the nearly trench parallel slip on the Puerto Rico subduction interface to the more perpendicular subduction slip beneath Hispaniola. The observations and modeling suggest that subduction-induced strike-slip seismic hazard to Puerto Rico may be smaller than previously assumed but the hazard to Hispaniola remains high. Copyright 2004 by the American Geophysical Union.
NASA Astrophysics Data System (ADS)
Ghalayini, Ramadan; Daniel, Jean-Marc; Homberg, Catherine; Nader, Fadi
2015-04-01
Analogue sandbox modeling is a tool to simulate deformation style and structural evolution of sedimentary basins. The initial goal is to test what is the effect of inherited and crustal structures on the propagation, evolution, and final geometry of major strike-slip faults at the boundary between two tectonic plates. For this purpose, we have undertaken a series of analogue models to validate and reproduce the structures of the Levant Fracture System, a major NNE-SSW sinistral strike-slip fault forming the boundary between the Arabian and African plates. Onshore observations and recent high quality 3D seismic data in the Levant Basin offshore Lebanon demonstrated that Mesozoic ENE striking normal faults were reactivated into dextral strike-slip faults during the Late Miocene till present day activity of the plate boundary which shows a major restraining bend in Lebanon with a ~ 30°clockwise rotation in its trend. Experimental parameters consisted of a silicone layer at the base simulating the ductile crust, overlain by intercalated quartz sand and glass sand layers. Pre-existing structures were simulated by creating a graben in the silicone below the sand at an oblique (>60°) angle to the main throughgoing strike-slip fault. The latter contains a small stepover at depth to create transpression during sinistral strike-slip movement and consequently result in mountain building similarly to modern day Lebanon. Strike-slip movement and compression were regulated by steady-speed computer-controlled engines and the model was scanned using a CT-scanner continuously while deforming to have a final 4D model of the system. Results showed that existing normal faults were reactivated into dextral strike-slip faults as the sinistral movement between the two plates accumulated. Notably, the resulting restraining bend is asymmetric and segmented into two different compartments with differing geometries. One compartment shows a box fold anticline, while the second shows an asymmetric anticline. Thus, analogue modeling has validated observation in seismic data and onshore geology whereby Mount Lebanon and adjacent folds exhibit similar compartmentalization and geometric dissimilarities along the Levant Fracture System. We suggest that the presence of inherited structures will affect to a certain extent the geometry of restraining bends and control the evolution of large strike-slip faults passing through.
Changes in foot and shank coupling due to alterations in foot strike pattern during running.
Pohl, Michael B; Buckley, John G
2008-03-01
Determining if and how the kinematic relationship between adjacent body segments changes when an individual's gait pattern is experimentally manipulated can yield insight into the robustness of the kinematic coupling across the associated joint(s). The aim of this study was to assess the effects on the kinematic coupling between the forefoot, rearfoot and shank during ground contact of running with alteration in foot strike pattern. Twelve subjects ran over-ground using three different foot strike patterns (heel strike, forefoot strike, toe running). Kinematic data were collected of the forefoot, rearfoot and shank, which were modelled as rigid segments. Coupling at the ankle-complex and midfoot joints was assessed using cross-correlation and vector coding techniques. In general good coupling was found between rearfoot frontal plane motion and transverse plane shank rotation regardless of foot strike pattern. Forefoot motion was also strongly coupled with rearfoot frontal plane motion. Subtle differences were noted in the amount of rearfoot eversion transferred into shank internal rotation in the first 10-15% of stance during heel strike running compared to forefoot and toe running, and this was accompanied by small alterations in forefoot kinematics. These findings indicate that during ground contact in running there is strong coupling between the rearfoot and shank via the action of the joints in the ankle-complex. In addition, there was good coupling of both sagittal and transverse plane forefoot with rearfoot frontal plane motion via the action of the midfoot joints.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-04
... at $145 per share would carry a total deliverable value of $145,000, and the strike price would be... Jumbo option strike price of $145 was trading at $146 per share, the intrinsic $1 per share value would... Shares Deliverable Upon Exercise 100 shares........ 1,000 shares Strike Price if underlying is 45 45 $45...
ERIC Educational Resources Information Center
Ineme, Kubiat M.; Ineme, Mfon E.
2016-01-01
The Nigerian tertiary educational system has been ravaged by incessant strike action, which appears to defy all attempts to find solutions. This paper reports on a study that examines the impact of job satisfaction and burnout on attitudes towards strike actions among employees of a Nigerian university. A total of 576 employees participated in the…
ERIC Educational Resources Information Center
Cross, Rod; Lindsey, Crawford
2018-01-01
An ice hockey player can strike a puck at speeds up to about 45 m/s (100 mph) using a technique known as the slap shot. There is nothing unusual about the speed, since golf balls, tennis balls, and baseballs can also be projected at that speed or even higher. The unusual part is that the player strikes the ice before striking the puck, causing the…
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2011-04-13
... Rule Change To Expand the $2.50 Strike Price Program April 8, 2011. Pursuant to Section 19(b)(1) of the... expand the $2.50 Strike Price program. The text of the proposed rule change is available on the Exchange... proposed rule change is to expand the current $2.50 Strike Price Program (``Program'') \\5\\ to permit the...
F-22 Operational Squadron and T-38 Detachment Beddown at Tyndall Air Force Base, Florida
2011-08-01
tactics, radar employment, identification, weapons employment, defensive response, electronic countermeasures, and electronic counter...use, and electronic countermeasures. Warning Area, MOA, and ATCAA 2,000 AGL to 60,000 MSL 0.75 to 1.5 hour (Dissimilar) Air Combat...night), air refueling, and strike-force rendezvous, conducting air-to-ground strikes, strike force defense and escort, air intercepts, electronic
Joint Strike Figher Acquisition: Mature Critical Technologies Needed to Reduce Risks
2001-10-01
Reduce Risks GAO-02-39 Report Documentation Page Report Date 00OCT2001 Report Type N/A Dates Covered (from... to) - Title and Subtitle JOINT STRIKE...FIGHTER ACQUISITION: Mature Critical Technologies Needed to Reduce Risks Contract Number Grant Number Program Element Number Author(s) Project...1Joint Strike Fighter Acquisition: Development Schedule Should Be Changed to Reduce Risks (GAO/T-NSIAD-00-132
2014-10-01
Resource JSF Joint Strike Fighter JPATS Joint Primary Aircraft Training System USMC United States Marine Corps USAF United States Air Force LIST...Surface Anthropometry Resource (CAESAR) was developed for the Joint Strike Fighter (JSF) program. The ACSS was intended to replace the JSF-CAESAR...an aircrew sample was made in 2003 by Hudson et al. They extracted a subset, named JSF CAESAR (Joint Strike Fighter), from the Civilian American and
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-06
... LLC To Expand the $2.50 Strike Price Program March 31, 2011. Pursuant to Section 19(b)(1) of the... proposes to amend Commentary .07 to NYSE Amex Rule 903 to expand the $2.50 Strike Price Program. The text... expand the current $2.50 Strike Price Program (``Program'')\\3\\ to permit the listing of options with $2...
NASA Astrophysics Data System (ADS)
Mullen, Kaitlyn Allen
North Atlantic right whales (Eubalaena glacialis ) are among the world's most endangered cetaceans. Although protected from commercial whaling since 1949, North Atlantic right whales exhibit little to no population growth. Ship strike mortality is the leading known cause of North Atlantic right whale mortality. North Atlantic right whales exhibit developed auditory systems, and vocalize in the frequency range that dominates ship acoustic signatures. With no behavioral audiogram published, current literature assumes these whales should be able to acoustically detect signals in the same frequencies they vocalize. Recorded ship acoustic signatures occur at intensities that are similar or higher to those recorded by vocalizing North Atlantic right whales. If North Atlantic right whales are capable of acoustically detecting oncoming ship, why are they susceptible to ship strike mortality? This thesis models potential acoustic impediments to North Atlantic right whale detection of oncoming ships, and concludes the presence of modeled and observed bow null effect acoustic shadow zones, located directly ahead of oncoming ships, are likely to impair the ability of North Atlantic right whales to detect and/or localize oncoming shipping traffic. This lack of detection and/or localization likely leads to a lack of ship strike avoidance, and thus contributes to the observed high rates of North Atlantic right whale ship strike mortality. I propose that North Atlantic right whale ship strike mortality reduction is possible via reducing and/or eliminating the presence of bow null effect acoustic shadow zones. This thesis develops and tests one method for bow null effect acoustic shadow zone reduction on five ships. Finally, I review current United States policy towards North Atlantic right whale ship strike mortality in an effort to determine if the bow null effect acoustic shadow zone reduction method developed is a viable method for reducing North Atlantic right whale ship strike mortality within United States waters. I recommend that future work include additional prototype modifications and testing, application for a marine mammal scientific take authorization permit to test the modified prototype on multiple mysticete species, and continued interfacing of the prototype with evolving United States North Atlantic right whale ship strike reduction policies.
Kusky, Timothy M.
1997-01-01
The Mesozoic accretionary wedge of south-central Alaska is cut by an array of faults including dextral and sinistral strike-slip faults, synthetic and antithetic thrust faults, and synthetic and antithetic normal faults. The three fault sets are characterized by quartz ± calcite ± chlorite ± prehnite slickensides, and are all relatively late, i.e. all truncate ductile fabrics of the host rocks. Cross-cutting relationships suggest that the thrust fault sets predate the late normal and strike-slip fault sets. Together, the normal and strike-slip fault system exhibits orthorhombic symmetry. Thrust faulting shortened the wedge subhorizontally perpendicular to strike, and then normal and strike-slip faulting extended the wedge oblique to orogenic strike. Strongly curved slickenlines on some faults of each set reveal that displacement directions changed over time. On dip-slip faults (thrust and normal), slickenlines tend to become steeper with younger increments of slip, whereas on strike-slip faults, slickenlines become shallower with younger strain increments. These patterns may result from progressive exhumation of the accretionary wedge while the faults were active, with the curvature of the slickenlines tracking the change from a non-Andersonian stress field at depth to a more Andersonian system (σ1 or σ2 nearly vertical) at shallower crustal levels.We interpret this complex fault array as a progressive deformation that is one response to Paleocene-Eocene subduction of the Kula-Farallon spreading center beneath the accretionary complex because: (1) on the Kenai Peninsula, ENE-striking dextral faults of this array exhibit mutually cross-cutting relationships with Paleocene-Eocene dikes related to ridge subduction; and (2) mineralized strike-slip and normal faults of the orthorhombic system have yielded 40Ar/39Ar ages identical to near-trench intrusives related to ridge subduction. Both features are diachronous along-strike, having formed at circa 65 Ma in the west and 50 Ma in the east. Exhumation of deeper levels of the southern Alaska accretionary wedge and formation of this late fault array is interpreted as a critical taper adjustment to subduction of progressively younger oceanic lithosphere yielding a shallower basal de´collement dip as the Kula-Farallon ridge approached the accretionary prism. The late structures also record different kinematic regimes associated with subduction of different oceanic plates, before and after ridge subduction. Prior to triple junction passage, subduction of the Farallon plate occurred at nearly right angles to the trench axis, whereas after triple junction migration, subduction of the Kula plate involved a significant component of dextral transpression and northward translation of the Chugach terrane. The changes in kinematics are apparent in the sequence of late structures from: (1) thrusting; (2) near-trench plutonism associated with normal + strike-slip faulting; (3) very late gouge-filled dextral faults.
ST-segment elevation following lightning strike: case report and review of the literature.
Akın, Alper; Bilici, Meki; Demir, Fikri; Gözü Pirinççioğlu, Ayfer; Yıldırım, Ahmet
2015-01-01
Lightning strikes may cause injury to the heart, ranging from slight electrocardiographic changes to fatal damage. As heart injury is the most important cause of mortality in these patients, cardiac monitoring is crucial. Even though various ECG changes have been reported, published data on pathologic ST-segment changes is scarce. Herein, we present a seven-year old patient with ST-segment elevation following a lightning strike. There is not sufficient data regarding lightning-related myocardial ischemia. However, because of the similar effects of lightning strikes and high-voltage electric shocks, we believe myocardial injury related to lightning may be managed in the same manner as is cardiac involvement associated with electric shock.
Lightning strike protection of composites
NASA Astrophysics Data System (ADS)
Gagné, Martin; Therriault, Daniel
2014-01-01
Aircraft structures are being redesigned to use fiber-reinforced composites mainly due to their high specific stiffness and strength. One of the main drawbacks from changing from electrically conductive metals to insulating or semi-conducting composites is the higher vulnerability of the aircraft to lightning strike damage. The current protection approach consists of bonding a metal mesh to the surface of the composite structure, but this weight increase negatively impact the fuel efficiency. This review paper presents an overview of the lightning strike problematic, the regulations, the lightning damage to composite, the current protection solutions and other material or technology alternatives. Advanced materials such as polymer-based nanocomposites and carbon nanotube buckypapers are promising candidates for lightweight lightning strike protection technology.
NASA Astrophysics Data System (ADS)
Febriani, F.; Handayani, L.; Setyani, A.; Anggono, T.; Syuhada; Soedjatmiko, B.
2018-03-01
The dimensionality and regional strike analyses of the Cimandiri Fault, West Java, Indonesia have been investigated. The Cimandiri Fault consists of six segments. They are Loji, Cidadap, Nyalindung, Cibeber, Saguling and Padalarang segments. The magnetotelluric (MT) investigation was done in the Cibeber segment. There were 42 observation points of the magnetotelluric data, which were distributed along 2 lines. The magnetotelluric phase tensor has been applied to determine the dimensionality and regional strike of the Cibeber segment, Cimandiri Fault, West Java. The result of the dimensionality analysis shows that the range values of the skew angle value which indicate the dimensionality of the study area are -5 ≤ β ≥ 5. These values indicate if we would like to generate the subsurface model of the Cibeber segment by using the magnetotelluric data, it is safe to assume that the Cibeber segment has the 2-D. While the regional strike analysis presents that the regional strike of the Cibeber segment is about N70-80°E.
Leap and strike kinetics of an acoustically ‘hunting’ barn owl (Tyto alba)
Usherwood, James R.; Sparkes, Emily L.; Weller, Renate
2014-01-01
Barn owls are effective hunters of small rodents. One hunting technique is a leap from the ground followed by a brief flight and a plummeting ‘strike’ onto an acoustically targeted – and potentially entirely hidden – prey. We used forceplate measurements to derive kinetics of the leap and strike. Leaping performance was similar to reported values for guinea fowl. This is likely achieved despite the owl's considerably smaller size because of its relatively long legs and use of wing upstroke. Strikes appear deliberately forceful: impulses could have been spread over larger periods during greater deflections of the centre of mass, as observed in leaping and an alighting landing measurement. The strike, despite forces around 150 times that of a mouse body weight, is not thought to be crucial to the kill; rather, forceful strikes may function primarily to enable rapid penetration of leaf litter or snow cover, allowing grasping of hidden prey. PMID:24948629
Electrically conductive carbon fibre-reinforced composite for aircraft lightning strike protection
NASA Astrophysics Data System (ADS)
Katunin, Andrzej; Krukiewicz, Katarzyna; Turczyn, Roman; Sul, Przemysław; Bilewicz, Marcin
2017-05-01
Aircraft elements, especially elements of exterior fuselage, are subjected to damage caused by lightning strikes. Due to the fact that these elements are manufactured from polymeric composites in modern aircraft, and thus, they cannot conduct electrical charges, the lightning strikes cause burnouts in composite structures. Therefore, the effective lightning strike protection for such structures is highly desired. The solution presented in this paper is based on application of organic conductive fillers in the form of intrinsically conducting polymers and carbon fabric in order to ensure electrical conductivity of whole composite and simultaneously retain superior mechanical properties. The presented studies cover synthesis and manufacturing of the electrically conductive composite as well as its characterization with respect to mechanical and electrical properties. The performed studies indicate that the proposed material can be potentially considered as a constructional material for aircraft industry, which characterizes by good operational properties and low cost of manufacturing with respect to current lightning strike protection materials solutions.
An analysis of how The Irish Times portrayed Irish nursing during the 1999 strike.
Clarke, J; O'Neill, C S
2001-07-01
The aim of this article is to explore the images of nursing that were presented in the media during the recent industrial action by nurses and midwives in the Republic of Ireland. Although both nurses and midwives took industrial strike action, the strike was referred to as 'the nurses' strike' and both nurses and midwives were generally referred to by the generic term 'nurses'. Data were gathered from the printed news media of The Irish Times over a period of one month--4 October to 4 November 1999--which included the nine days of the strike. Although we limited the source of our data to just one newspaper, the findings do provide an image of how nurses and nursing care are viewed by both health professionals and the public. This image appeared to give a higher value to masculine cultural codes and the performance of technical skills, whereas acts associated with feminine cultural codes of caring were considered of lower value.
2007 Precision Strike Winter Roundtable - Precision Engagement - Strategic Context for the Long War
2007-02-01
but also to import Mercedes - Benzes , pricey cognacs and other luxury items to buy loyalty. Washington fears that North Korea could decide to use its...Cappuccio—Executive Vice President and General Manager, Advanced Development Programs & Strategic Planning, Lockheed Martin Company JOINT INNOVATION ... Innovative Minds Lockheed Martin Aeronautics Company Frank Cappuccio, February 1, 2007 Precision Strike Winter Roundtable “Long Range Strike Weapons” 2Lockheed
High current lightning test of space shuttle external tank lightning protection system
NASA Technical Reports Server (NTRS)
Mumme, E.; Anderson, A.; Schulte, E. H.
1977-01-01
During lift-off, the shuttle launch vehicle (external tank, solid rocket booster and orbiter) may be subjected to a lightning strike. Tests of a proposed lightning protection method for the external tank and development materials which were subjected to simulated lightning strikes are described. Results show that certain of the high resistant paint strips performed remarkably well in diverting the 50 kA lightning strikes.
The physician and prison hunger strikes: reflecting on the experience in Turkey.
Oguz, N Y; Miles, S H
2005-03-01
The medical ethics of a physician's relationship with a prisoner who is participating in a collective hunger strike has become a major public, professional, and governmental concern in The Republic of Turkey. This article examines the Turkish experience and debate about physician ethics during prison hunger strikes. It is hoped that this analysis will be of use to those formulating policy in similar situations.
Influence of step length and landing pattern on patellofemoral joint kinetics during running.
Willson, J D; Ratcliff, O M; Meardon, S A; Willy, R W
2015-12-01
Elevated patellofemoral joint kinetics during running may contribute to patellofemoral joint symptoms. The purpose of this study was to test for independent effects of foot strike pattern and step length on patellofemoral joint kinetics while running. Effects were tested relative to individual steps and also taking into account the number of steps required to run a kilometer with each step length. Patellofemoral joint reaction force and stress were estimated in 20 participants running at their preferred speed. Participants ran using a forefoot strike and rearfoot strike pattern during three different step length conditions: preferred step length, long (+10%) step length, and short (-10%) step length. Patellofemoral kinetics was estimated using a biomechanical model of the patellofemoral joint that accounted for cocontraction of the knee flexors and extensors. We observed independent effects of foot strike pattern and step length. Patellofemoral joint kinetics per step was 10-13% less during forefoot strike conditions and 15-20% less with a shortened step length. Patellofemoral joint kinetics per kilometer decreased 12-13% using a forefoot strike pattern and 9-12% with a shortened step length. To the extent that patellofemoral joint kinetics contribute to symptoms among runners, these running modifications may be advisable for runners with patellofemoral pain. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Assessing risks to humans from invasive Burmese pythons in Everglades National Park, Florida, USA
Reed, Robert N.; Snow, Ray W.
2014-01-01
Invasive Burmese pythons (Python molurus bivittatus) are now established across a large area of southern Florida, USA, including all of Everglades National Park (NP). The presence of these large-bodied snakes in the continental United States has attracted intense media attention, including regular reference to the possibility of these snakes preying on humans. Over the course of a decade (2003–2012), we solicited reports of apparently unprovoked strikes directed at humans in Everglades NP. We summarize the circumstances surrounding each of the 5 reported incidents, which occurred between 2006 and 2012. All strikes were directed toward biologists moving through flooded wetlands; 2 strikes resulted in minor injury and none resulted in constriction. We consider most of these strikes to be cases of “mistaken identity,” in which the python initiated a strike at a potential prey item but aborted its predatory behavior prior to constriction and ingestion. No strikes are known to have been directed at park visitors despite visitation rates averaging over one million per year during this period. We conclude that while risks to humans should not be completely discounted, the relative risk of a human being killed by a python in Everglades NP appears to be extremely low.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Canavan, G.H.
This note studies the impact of maximizing the stability index rather than minimizing the first strike cost in choosing offensive missile allocations. It does so in the context of a model in which exchanges between vulnerable missile forces are modeled probabilistically, converted into first and second strike costs through approximations to the value target sets at risk, and the stability index is taken to be their ratio. The value of the allocation that minimizes the first strike cost for both attack preferences are derived analytically. The former recovers results derived earlier. The latter leads to an optimum at unity allocationmore » for which the stability index is determined analytically. For values of the attack preference greater than about unity, maximizing the stability index increases the cost of striking first 10--15%. For smaller values of the attack preference, maximizing the index increases the second strike cost a similar amount. Both are stabilizing, so if both sides could be trusted to target on missiles in order to minimize damage to value and maximize stability, the stability index for vulnerable missiles could be increased by about 15%. However, that would increase the cost to the first striker by about 15%. It is unclear why--having decided to strike--he would do so in a way that would increase damage to himself.« less
Sierra, Eva; Fernández, Antonio; Espinosa de los Monteros, Antonio; Arbelo, Manuel; Díaz-Delgado, Josué; Andrada, Marisa; Herráez, Pedro
2014-01-01
Ship strikes are a major issue for the conservation of may cetacean species. Certain gross and microscopic criteria have been previously reported for establishing a diagnosis of death due to ship strikes in these animals. However, some ship-strike injuries may be masked by advanced carcass decomposition and may be undetectable due to restricted access to the animals. In this report we describe histopathological muscular findings in 13 cetaceans with sharp trauma from ship strikes as the cause of death. Skeletal muscle samples were taken from the incision site and from the main locomotor muscle, the longissimus dorsi, in areas not directly affected by the sharp injury. The microscopic findings in tissues from both sites mainly consisted of haemorrhages; oedema; flocculent, granular or/and hyalinised segmentary degeneration; contraction band necrosis; and discoid degeneration or fragmentation of myofibres. We propose that skeletal muscle histopathology provides evidence of ante-mortem injuries even if the sample was taken elsewhere in the carcass and not only within or adjacent to the sharp trauma site and despite the advanced decomposition of some of the carcasses. This method helps to establish the diagnosis of ship strike as the cause of death. PMID:24551162
Joint contact loading in forefoot and rearfoot strike patterns during running.
Rooney, Brandon D; Derrick, Timothy R
2013-09-03
Research concerning forefoot strike pattern (FFS) versus rearfoot strike pattern (RFS) running has focused on the ground reaction force even though internal joint contact forces are a more direct measure of the loads responsible for injury. The main purpose of this study was to determine the internal loading of the joints for each strike pattern. A secondary purpose was to determine if converted FFS and RFS runners can adequately represent habitual runners with regards to the internal joint loading. Using inverse dynamics to calculate the net joint moments and reaction forces and optimization techniques to estimate muscle forces, we determined the axial compressive loading at the ankle, knee, and hip. Subjects consisted of 15 habitual FFS and 15 habitual RFS competitive runners. Each subject ran at a preferred running velocity with their habitual strike pattern and then converted to the opposite strike pattern. Plantar flexor muscle forces and net ankle joint moments were greater in the FFS running compared to the RFS running during the first half of the stance phase. The average contact forces during this period increased by 41.7% at the ankle and 14.4% at the knee joint during FFS running. Peak ankle joint contact force was 1.5 body weights greater during FFS running (p<0.05). There was no evidence to support a difference between habitual and converted running for joint contact forces. The increased loading at the ankle joint for FFS is an area of concern for individuals considering altering their foot strike pattern. Copyright © 2013 Elsevier Ltd. All rights reserved.
Kuhman, Daniel; Melcher, Daniel; Paquette, Max R
2016-01-01
The purpose of this study was to investigate the interaction of foot strike and common speeds on sagittal plane ankle and knee joint kinetics in competitive rear foot strike (RFS) runners when running with a RFS pattern and an imposed forefoot strike (FFS) pattern. Sixteen competitive habitual male RFS runners ran at two different speeds (i.e. 8 and 6 min mile(-1)) using their habitual RFS and an imposed FFS pattern. A repeated measures analysis of variance was used to assess a potential interaction between strike pattern and speed for selected ground reaction force (GRF) variables and, sagittal plane ankle and knee kinematic and kinetic variables. No foot strike and speed interaction was observed for any of the kinetic variables. Habitual RFS yielded a greater loading rate of the vertical GRF, peak ankle dorsiflexor moment, peak knee extensor moment, peak knee eccentric extensor power, peak dorsiflexion and sagittal plane knee range of motion compared to imposed FFS. Imposed FFS yielded greater maximum vertical GRF, peak ankle plantarflexor moment, peak ankle eccentric plantarflexor power and sagittal plane ankle ROM compared to habitual RFS. Consistent with previous literature, imposed FFS in habitual RFS reduces eccentric knee extensor and ankle dorsiflexor involvement but produce greater eccentric ankle plantarflexor action compared to RFS. These acute differences between strike patterns were independent of running speeds equivalent to typical easy and hard training runs in competitive male runners. Current findings along with previous literature suggest differences in lower extremity kinetics between habitual RFS and imposed FFS running are consistent among a variety of runner populations.
From Threat to Fear: The neural organization of defensive fear systems in humans
Mobbs, Dean; Marchant, Jennifer L; Hassabis, Demis; Seymour, Ben; Tan, Geoffrey; Gray, Marcus; Petrovic, Predrag; Dolan, Raymond J.; Frith, Christopher D.
2009-01-01
Post-encounter and circa-strike defensive contexts represent two adaptive responses to potential and imminent danger. In the context of a predator, the post-encounter reflects the initial detection of the potential threat, whilst the circa-strike is associated with direct predatory attack. We used fMRI to investigate the neural organization of anticipation and avoidance of artificial predators with high or low probability of capturing the subject across analogous post-encounter and circa-strike contexts of threat. Consistent with defense systems models, post-encounter threat elicited activity in forebrain areas including subgenual anterior cingulate cortex (sgACC), hippocampus and amygdala. Conversely, active avoidance during circa-strike threat increased activity in mid-dorsal ACC and midbrain areas. During the circa-strike condition, subjects showed increased coupling between the midbrain and mid-dorsal ACC and decreased coupling with the sgACC, amygdala and hippocampus. Greater activity was observed in the right pregenual ACC for high compared to low probability of capture during circa-strike threat. This region showed decreased coupling with the amygdala, insula and ventromedial prefrontal cortex. Finally, we found that locomotor errors correlated with subjective reports of panic for the high compared to low probability of capture during the circa-strike threat and these panic-related locomotor errors were correlated with midbrain activity. These findings support models suggesting that higher forebrain areas are involved in early threat responses, including the assignment and control of fear, whereas as imminent danger results in fast, likely “hard-wired”, defensive reactions mediated by the midbrain. PMID:19793982
Effects of malicious ocular laser exposure in commercial airline pilots.
Palakkamanil, Mathew M; Fielden, Michael P
2015-12-01
Intentional malicious laser strikes on commercial pilots are committed by individuals who target a laser into airplane cockpits during takeoff and landing. Because laser exposure to pilots is a relatively new but growing occurrence, our study investigates the ocular effect of this laser exposure in pilots. Retrospective chart review by a single ophthalmologist. All commercial airline pilots (58 male, 3 female) who experienced a laser strike while flying between April 2012 and November 2014 who presented to our clinic were included. A retrospective chart review was performed in a retinal specialist's practice. Ocular assessment was performed within 3 days of laser exposure. A complete ophthalmic evaluation was conducted, including Early Treatment Diabetic Retinopathy Study visual acuity, colour vision, visual fields, intraocular pressure, slit-lamp examination, dilated fundus examination, colour fundus photographs, and ocular coherence tomography. Sixty-four laser strike incidents involving commercial pilots were included. All pilots in the study experienced some degree of immediate ocular irritation or light sensitivity. No definite cases of ocular damage were attributed to laser strikes. No pilot had any functional ocular deficits. Our study revealed that laser strikes on aircraft did not result in permanent visual functional or structural deficits. However, laser strikes cause immediate visual effects, including glare, flash blindness, and ocular irritation that can interfere with a pilot's visual function. Given the widespread accessibility of high-power lasers and the rapid increase in incidents, laser strikes threaten to jeopardize aviation safety unless effective preventative measures are put in place. Copyright © 2015 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.
The Advantage of Standing Up to Fight and the Evolution of Habitual Bipedalism in Hominins
Carrier, David R.
2011-01-01
Background Many quadrupedal species stand bipedally on their hindlimbs to fight. This posture may provide a performance advantage by allowing the forelimbs to strike an opponent with the range of motion that is intrinsic to high-speed running, jumping, rapid braking and turning; the range of motion over which peak force and power can be produced. Methodology/Principal Findings To test the hypothesis that bipedal (i.e., orthograde) posture provides a performance advantage when striking with the forelimbs, I measured the force and energy produced when human subjects struck from “quadrupedal” (i.e., pronograde) and bipedal postures. Downward and upward directed striking energy was measured with a custom designed pendulum transducer. Side and forward strikes were measured with a punching bag instrumented with an accelerometer. When subjects struck downward from a bipedal posture the work was 43.70±12.59% (mean ± S.E.) greater than when they struck from a quadrupedal posture. Similarly, 47.49±17.95% more work was produced when subjects struck upward from a bipedal stance compared to a quadrupedal stance. Importantly, subjects did 229.69±44.19% more work in downward than upward directed strikes. During side and forward strikes the force impulses were 30.12±3.68 and 43.04±9.00% greater from a bipedal posture than a quadrupedal posture, respectively. Conclusions/Significance These results indicate that bipedal posture does provide a performance advantage for striking with the forelimbs. The mating systems of great apes are characterized by intense male-male competition in which conflict is resolved through force or the threat of force. Great apes often fight from bipedal posture, striking with both the fore- and hindlimbs. These observations, plus the findings of this study, suggest that sexual selection contributed to the evolution of habitual bipedalism in hominins. PMID:21611167
Impaction Force Influences Taper-Trunnion Stability in Total Hip Arthroplasty.
Danoff, Jonathan R; Longaray, Jason; Rajaravivarma, Raga; Gopalakrishnan, Ananthkrishnan; Chen, Antonia F; Hozack, William J
2018-07-01
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.
Mesozoic to Cenozoic tectonic transition process in Zhanhua Sag, Bohai Bay Basin, East China
NASA Astrophysics Data System (ADS)
Cheng, Yanjun; Wu, Zhiping; Lu, Shunan; Li, Xu; Lin, Chengyan; Huang, Zheng; Su, Wen; Jiang, Chao; Wang, Shouye
2018-04-01
The Zhanhua sag is part of the Bohai Bay intracontinental basin system that has developed since the Mesozoic in East China. The timing of this basin system coincides with the final assembly of East Asia and the development of Western Pacific-type plate margin. Here we use 3-D seismic and core log data to investigate the evolution of this basin and discuss its broad tectonic settings. Our new structural study of Zhanhua sag suggests that there are four major tectonic transitions occurred in the Bohai Bay Basin during Mesozoic and Cenozoic: (1) The first tectonic transition was from stable Craton to thrusting during the Triassic, mainly caused by the South China Block's subduction northward beneath the North China Block, which induced the formation of the NW-striking thrust faults. (2) The second tectonic transition was mainly characterized by a change from compression to extension, which can be further divided into two-stages. At the first stage, two episodes of NW-SE shortening occurred in East Asia during Early-Middle Jurassic and Late Jurassic-earliest Cretaceous, respectively. At the second stage, the extension and left-lateral shearing took place during Early Cretaceous while compression occurred during Late Cretaceous. The NW-striking thrust faults changed to normal faults and the NNE-striking left-lateral strike-slip faults started to influence the eastern part of the basin. (3) The third transition occurred when the NW-SE extension and NNE-striking right-lateral shearing started to form during Paleogene, and the peak deformation happen around 40 Ma due to the change of the subduction direction of Pacific Plate relative to Eurasia Plate. The NE-striking normal faults are the main structure, and the pre-existing NNE-striking strike-slip faults changed from left-lateral to right-lateral. (4) The fourth transition saw the regional subsidence during Neogene, which was probably caused by the India-Asia "Hard collision" between 25 and 20 Ma.
NASA Astrophysics Data System (ADS)
Andrade, Daniel; van Wyk de Vries, Benjamin; Robin, Claude
2014-05-01
Volcano-basement interactions can deeply determine the structural development of volcanoes basically by the propagation of stress and strain fields from the basement into the volcanic edifice, and vice versa. An extensively studied case of such interactions is the propagation of a strike-slip fault through a volcanic edifice, which gives place to a strong tendency of major volcanic construction and destruction events to occur in a sub-parallel trend with respect to the strike of the fault. During precedent studies, however, both scaled and natural prototypes have always considered that the surfaces on which volcanoes stand (i.e. the sub-volcanic slope) are horizontal. The scaled experiments presented here show that the dip-angle and dip-direction of the subvolcanic slopes can systematically and significantly change the deformation patterns developed by the volcanic edifice during strike-slip faulting. When the dip-direction of the sub-volcanic slope and the strike of the fault are nearly parallel, an increased development and concentration of the deformation on the down-slope side of the volcanic cone occurs. In medium to long-term, this would imply again a tendency of major volcanic structures growing in a sub-parallel trend with respect to the strike of the fault, but with one preferred direction: that of the dip-direction. In the experiments, the dip-direction of the sub-volcanic slope was set progressively oblique, up to perpendicular, with respect to the strike of the fault by: 1) rotating in the same sense as the strike-slip fault, or 2) rotating in the opposite sense as the fault. In both cases, the downslope side of the volcanic cone still concentrates the deformation, but the deformed sectors progressively rotate which results in a structural development (construction and destruction) of the edifice occurring clearly oblique with respect to the strike of the fault. Imbabura volcano (Ecuador) is traversed by the strike-slip El Angel-Río Ambi fault, whose sense of movement (left- or right-lateral) has not been clearly established yet. Aditionally, Imbabura has been constructed on the NW, medium to lower flank of the neighbor Cubilche volcano. The application of the experimental results presented above to the case of Imbabura volcano helps to understand the particular structure of this volcano which displays a complex history of construction and destruction events. Additionally, the experiments strongly suggests that the El Angel-Río Ambi fault is left-lateral.
Fredericks, William; Swank, Seth; Teisberg, Madeline; Hampton, Bethany; Ridpath, Lance; Hanna, Jandy B
2015-06-01
Minimalist running footwear has grown increasingly popular. Prior studies that have compared lower extremity biomechanics in minimalist running to traditional running conditions are largely limited to a single running velocity. This study compares the effects of running at various speeds on foot strike pattern, stride length, knee angles and ankle angles in traditional, barefoot, and minimalist running conditions. Twenty-six recreational runners (19-46 years of age) ran on a treadmill at a range of speeds (2.5-4.0 m·sec(-1)). Subjects ran with four different footwear conditions: personal, standard, and minimalist shoes and barefoot. 3D coordinates from video data were collected. The relationships between speed, knee and ankle angles at foot strike and toe-off, relative step length, and footwear conditions were evaluated by ANCOVA, with speed as the co-variate. Distribution of non-rearfoot strike was compared across shod conditions with paired t-tests. Non-rearfoot strike distribution was not significantly affected by speed, but was different between shod conditions (p < 0.05). Footwear condition and speed significantly affected ankle angle at touchdown, independent of one another (F [3,71] = 10.28, p < 0.001), with barefoot and minimalist running exhibiting greater plantarflexion at foot strike. When controlling for foot strike style, barefoot and minimalist runners exhibited greater plantarflexion than other conditions (p < 0.05). Ankle angle at lift-off and relative step length exhibited a significant interaction between speed and shod condition. Knee angles had a significant relationship with speed, but not with footwear. There is a clear influence of footwear, but not speed, on foot strike pattern. Additionally, speed and footwear predict ankle angles (greater plantarflexion at foot strike) and may have implications for minimalist runners and their risk of injury. Long-term studies utilizing various speeds and habituation times are needed. Key pointsFoot strike style does not change with speed, but does change with shod condition, with minimalist shoes exhibiting an intermediate distribution of forefoot strikes between barefoot and traditional shoes.Plantarflexion at touchdown does change with speed and with shoe type, with barefoot and minimalist shoes exhibiting a greater plantarflexion angle than traditional running shoes.Knee angles change with speed in all shod conditions, but knee flexion at touchdown is not different between shod conditions.Relative step length changes with speed and shod condition, but there is an interaction between these variables such that step length increases more quickly in traditional shoes as speed increases.
Fredericks, William; Swank, Seth; Teisberg, Madeline; Hampton, Bethany; Ridpath, Lance; Hanna, Jandy B.
2015-01-01
Minimalist running footwear has grown increasingly popular. Prior studies that have compared lower extremity biomechanics in minimalist running to traditional running conditions are largely limited to a single running velocity. This study compares the effects of running at various speeds on foot strike pattern, stride length, knee angles and ankle angles in traditional, barefoot, and minimalist running conditions. Twenty-six recreational runners (19-46 years of age) ran on a treadmill at a range of speeds (2.5-4.0 m·sec-1). Subjects ran with four different footwear conditions: personal, standard, and minimalist shoes and barefoot. 3D coordinates from video data were collected. The relationships between speed, knee and ankle angles at foot strike and toe-off, relative step length, and footwear conditions were evaluated by ANCOVA, with speed as the co-variate. Distribution of non-rearfoot strike was compared across shod conditions with paired t-tests. Non-rearfoot strike distribution was not significantly affected by speed, but was different between shod conditions (p < 0.05). Footwear condition and speed significantly affected ankle angle at touchdown, independent of one another (F [3,71] = 10.28, p < 0.001), with barefoot and minimalist running exhibiting greater plantarflexion at foot strike. When controlling for foot strike style, barefoot and minimalist runners exhibited greater plantarflexion than other conditions (p < 0.05). Ankle angle at lift-off and relative step length exhibited a significant interaction between speed and shod condition. Knee angles had a significant relationship with speed, but not with footwear. There is a clear influence of footwear, but not speed, on foot strike pattern. Additionally, speed and footwear predict ankle angles (greater plantarflexion at foot strike) and may have implications for minimalist runners and their risk of injury. Long-term studies utilizing various speeds and habituation times are needed. Key points Foot strike style does not change with speed, but does change with shod condition, with minimalist shoes exhibiting an intermediate distribution of forefoot strikes between barefoot and traditional shoes. Plantarflexion at touchdown does change with speed and with shoe type, with barefoot and minimalist shoes exhibiting a greater plantarflexion angle than traditional running shoes. Knee angles change with speed in all shod conditions, but knee flexion at touchdown is not different between shod conditions. Relative step length changes with speed and shod condition, but there is an interaction between these variables such that step length increases more quickly in traditional shoes as speed increases. PMID:25983575
NASA Astrophysics Data System (ADS)
Dietrich, Andreas; Gutierrez, Ronald; Nelson, Eric P.; Layer, Paul W.
2012-03-01
The San José district is located in the northwest part of the Deseado massif and hosts a number of epithermal Ag-Au quartz veins of intermediate sulfidation style, including the Huevos Verdes vein system. Veins are hosted by andesitic rocks of the Bajo Pobre Formation and locally by rhyodacitic pyroclastic rocks of the Chon Aike Formation. New 40Ar/39Ar constraints on the age of host rocks and mineralization define Late Jurassic ages of 151.3 ± 0.7 Ma to 144.7 ± 0.1 Ma for volcanic rocks of the Bajo Pobre Formation and of 147.6 ± 1.1 Ma for the Chon Aike Formation. Illite ages of the Huevos Verdes vein system of 140.8 ± 0.2 and 140.5 ± 0.3 Ma are 4 m.y. younger than the volcanic host rock unit. These age dates are among the youngest reported for Jurassic volcanism in the Deseado massif and correlate well with the regional context of magmatic and hydrothermal activity. The Huevos Verdes vein system has a strike length of 2,000 m, with several ore shoots along strike. The vein consists of a pre-ore stage and three main ore stages. Early barren quartz and chalcedony are followed by a mottled quartz stage of coarse saccharoidal quartz with irregular streaks and discontinuous bands of sulfide-rich material. The banded quartz-sulfide stage consists of sulfide-rich bands alternating with bands of quartz and bands of chlorite ± illite. Late-stage sulfide-rich veinlets are associated with kaolinite gangue. Ore minerals are argentite and electrum, together with pyrite, sphalerite, galena, chalcopyrite, minor bornite, covellite, and ruby silver. Wall rock alteration is characterized by narrow (< 3 m) halos of illite and illite/smectite next to veins, grading outward into propylitic alteration. Gangue minerals are dominantly massive quartz intergrown with minor to accessory adularia. Epidote, illite, illite/smectite, and, preferentially at deeper levels, Fe-chlorite gangue indicate near-neutral pH hydrothermal fluids at temperatures of >220°C. Kaolinite occurring with the late sulfide-rich veinlet stage indicates pH < 4 and a temperature of <200°C. The Huevos Verdes system has an overall strike of 325°, dipping on average 65° NE. The orientations of individual ore shoots are controlled by vein strike and intersecting north-northwest-striking faults. We propose a structural model for the time of mineralization of the San José district, consisting of a conjugate shear pair of sinistral north-northwest- and dextral west-northwest-striking faults that correspond to R and R' in the Riedel shear model and that are related to master faults (M) of north-northeast-strike. Veins of 315° strike can be interpreted as nearly pure extensional fractures (T). Variations in vein strike predict an induced sinistral shear component for strike directions of >315°, whereas strike directions of <315° are predicted with an induced dextral strike-slip movement. The components of the structural model appear to be present on a regional scale and are not restricted to the San José district.
A Review of Research on Bird Impacting on Jet Engines
NASA Astrophysics Data System (ADS)
Jin, Yuecheng
2018-03-01
Bird strikes can lead to permanent deformations, sudden decrease of thrust, even engine failure during the flight. Bird strikes on rotating blades can also cause slices of birds hitting other parts which may lead to greater damages. Bird strikes cannot be completely avoided. However, reduction of bird impacting on jet engines can be achieved by suitable design and manufacturing, through the mathematical modelling, simulation analysis and practical experiment of jet engines.
The 1984 direct strike lightning data, part 3
NASA Technical Reports Server (NTRS)
Thomas, Mitchel E.; Carney, Harold K.
1986-01-01
Data waveforms are presented which were obtained during the 1984 direct-strike lightning tests utilizing the NASA F106-B aircraft specially instrumented for lightning electromagnetic measurements. The aircraft was operated in the vicinity of the NASA Langley Research Center, Hampton, Virginia, in a thunderstorm environment to elicit strikes. Electromagnetic field data and conduction currents on the aircraft were recorded for attached lightning. This is part 3, consisting entirely of charts and graphs.
The Strategic and Political Impacts of Collateral Damage from Strike Warfare
2015-03-01
damage from strike warfare focuses on legal, humanitarian, and moral issues . To oversimplify, killing non-combatants is bad, but it happens, and not...humanitarian, and moral issues . To oversimplify, killing non- combatants is bad, but it happens, and not always by accident. Therefore, it is instructive...method of bombing. A significant amount of research on the effects of collateral damage from strike warfare focuses on humanitarian and moral issues
Competitive Advantage, Uncertainty, and Weapons Procurement: Striking Balance for the Future
2009-05-02
position of the Department of the Army, Department of Defense, or the U.S. Government. COMPETITIVE ADVANTAGE , UNCERTAINTY, AND WEAPONS PROCUREMENT: STRIKING...Competitive Advantage , Uncertainty, and Weapons Procurement: Striking Balance for the Future 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d...the right balance of investments all leading to a sustained competitive advantage . This paper presents an analysis of how effective this overhaul has
JPRS Report East Asia Southeast Asia
1987-06-16
QUALITY INSPECTED 6 19980610 113 ~«*tSTKIBUT10N STi Approved for public release; Distribution Unlimited REPRODUCEDBY U.S. DEPARTMENTOF COMMERCE...place. Since strikes are legal during a dispute of interest, and new matter bargaining Is interest bargaining, sanctity of agreement will inevitably...relation to a matter that Is the subject of a dis- pute of interest, strikes are legal . • The union will have the right to create a dispute and strike
Annotated Bibliography of Bird Hazards to Aircraft: Bird Strike Committee Citations 1967-1997.
1998-03-01
reduce losses from birdstrikes by applying state-of-the-art technologies to improve aircraft survivability to bird hazards and overall reduced cost-of... losses for the aviation industry from birds are estimated to exceed $1 billion annually. Recent birdstrikes involving significant loss -of-life and...aviation losses caused by birds. 2 CONTRIBUTING ORGANIZATIONS 2.1 Bird Strike Committee Europe The Bird Strike Committee Europe (BSCE) was formed in
[Hunger striking in prisons: ethics and the ethical and legal aspects].
García-Guerrero, J
2013-01-01
Hunger strike is a common form of protest in prisons and is a potential cause of many types of problems, both for the prison administration and the doctors who care for prisoners who participate in one. Issues of conflict of rights and obligations involved, and how to treat people who are subject to the Administration, which in this case takes the position of guarantor, have created major controversies over doctrine. Conscientious objection and the conflict of dual loyalty of doctors working in prisons are also issues closely linked to a prison hunger strike. In this paper we review the solution given to the problem of treatment of a prison hunger strike from three perspectives: ethics, ethical and legal.
The Case for Using Blunt-Tipped Lightning Rods as Strike Receptors.
NASA Astrophysics Data System (ADS)
Moore, C. B.; Aulich, G. D.; Rison, William
2003-07-01
Conventional lightning rods used in the United States have sharp tips, a practice derived from Benjamin Franklin's discovery of a means to obtain protection from lightning. However, the virtue of sharp tips for strike reception has never been established. An examination of the relevant physics shows that very strong electric fields are required above the tips of rods in order that they function as strike receptors but that the gradients of the field strength over sharp-tipped rods are so great that, at distances of a few millimeters, the local fields are often too weak for the development of upward-going streamers. In field tests, rods with rounded tips have been found to be better strike receptors than were nearby sharp-tipped rods.
Fracture network of the Ferron Sandstone Member of the Mancos Shale, east-central Utah, USA
Condon, S.M.
2003-01-01
The fracture network at the outcrop of the Ferron Sandstone Member of the Mancos Shale was studied to gain an understanding of the tectonic history of the region and to contribute data to studies of gas and water transmissivity related to the occurrence and production of coal-bed methane. About 1900 fracture readings were made at 40 coal outcrops and 62 sandstone outcrops in the area from Willow Springs Wash in the south to Farnham dome in the north of the study area in east-central Utah.Two sets of regional, vertical to nearly vertical, systematic face cleats were identified in Ferron coals. A northwest-striking set trends at a mean azimuth of 321??, and a northeast-striking set has a mean azimuth of 55??. Cleats were observed in all coal outcrops examined and are closely spaced and commonly coated with thin films of iron oxide.Two sets of regional, systematic joint sets in sandstone were also identified and have mean azimuths of 321?? and 34??. The joints of each set are planar, long, and extend vertically to nearly vertically through multiple beds; the northeast-striking set is more prevalent than the northwest-striking set. In some places, joints of the northeast-striking set occur in closely spaced clusters, or joint zones, flanked by unjointed rock. Both sets are mineralized with iron oxide and calcite, and the northwest-striking set is commonly tightly cemented, which allowed the northeast-striking set to propagate across it. All cleats and joints of these sets are interpreted as opening-mode (mode I) fractures. Abutting relations indicate that the northwest-striking cleats and joints formed first and were later overprinted by the northeast-striking cleats and joints. Burial curves constructed for the Ferron indicate rapid initial burial after deposition. The Ferron reached a depth of 3000 ft (1000 m) within 5.2 million years (m.y.), and this is considered a minimum depth and time for development of cleats and joints. The Sevier orogeny produced southeast-directed compressional stress at this time and is thought to be the likely mechanism for the northwest-striking systematic cleats and joints. The onset of the Laramide orogeny occurred at about 75 Ma, within 13.7 m.y. of burial, and is thought to be the probable mechanism for development of the northeast-striking systematic cleats and joints. Uplift of the Ferron in the late Tertiary contributed to development of butt cleats and secondary cross-joints and probably enhanced previously formed fracture sets. Using a study of the younger Blackhawk Formation as an analogy, the fracture pattern of the Ferron in the subsurface is probably similar to that at the surface, at least as far west as the Paradise fault and Joe's Valley graben. Farther to the west, on the Wasatch Plateau, the orientations of Ferron fractures may diverge from those measured at the outcrop. ?? 2003 Elsevier B.V. All rights reserved.
Xu, Xianrong; Ma, Xiaoli; Zhang, Yang; Xiong, Wei
2012-01-01
To comparatively analyze the disease data of nasal sinus between helicopter and (strike) fighter pilots under flying qualification, and then to provide references for aeromedical support as a significant part of new logistics service union in army, The CT data of nasal sinus in 138 pilots who accepted physical examination for change to new-type aircraft, were collected included 46 cases of helicopter pilots and 92 cases of (strike)fighter pilots). The incidence of chronic sinusitis and cyst of nasal sinus were computed respectively in helicopter pilots and (strike)fighter pilots. (1) Fourteen cases suffered from chronic sinusitis (6 cases of maxillary sinusitis, 4 cases of ethmoiditis and 4 cases of maxillary sinusitis and ethmoiditis) in helicopter pilots whose incidence rate of chronic sinusitis was 30.4% (14/46). Of which, 3 cases of antracele were treated. Twelve cases suffered from chronic sinusitis (8 cases of maxillary sinusitis, 1 case of ethmoiditis, 3 cases of maxillary sinusitis and ethmoiditis) in (strike)fighter pilots whose incidence of chronic sinusitis was 13.0% (12/92). Of which, 1 case of antracele was treated. The incidence of chronic sinusitis was higher in helicopter pilots than (strike) fighters pilots (Chi2 = 6.07, P < 0.05). (2) Four cases suffered from unilateral mucosa cysts in maxillary sinus in helicopter pilots whose incidence of cyst of nasal sinus was 8.7% (4/46). Ten cases suffered from mucosa cysts in maxillary sinus (unilateral 8 cases and bilateral 2 cases) in (strike) fighters pilots whose incidence of cyst of nasal sinus was 10.87% (10/92). The difference of the incidence of cyst of nasal sinus was not statistically significant between the helicopter pilots and(strike)fighters pilots. The cysts of nasal sinus did not need treatment in 14 cases of this group data. The incidence of symptomless chronic sinusitis and cyst of nasal sinus are high in pilots. It is related with repeatedly changes of atmosphere pressure during flying. But most chronic sinusitis and cyst of nasal sinus do not need treatment. The incidence of chronic sinusitis is higher in helicopter pilots than(strike)fighter pilots. It may be related with the environment of helicopter which have unclosed cockpit and load other aircrew.
Pohn, Howard A.
2000-01-01
Lateral ramps are zones where decollements change stratigraphic level along strike; they differ from frontal ramps, which are zones where decollements change stratigraphic level perpendicular to strike. In the Appalachian Mountains, the surface criteria for recognizing the subsurface presence of lateral ramps include (1) an abrupt change in wavelength or a termination of folds along strike, (2) a conspicuous change in the frequency of mapped faults or disturbed zones (extremely disrupted duplexes) at the surface, (3) long, straight river trends emerging onto the coastal plain or into the Appalachian Plateaus province, (4) major geomorphic discontinuities in the trend of the Blue Ridge province, (5) interruption of Mesozoic basins by cross-strike border faults, and (6) zones of modern and probable ancient seismic activity. Additional features related to lateral ramps include tectonic windows, cross-strike igneous intrusions, areas of giant landslides, and abrupt changes in Paleozoic sedimentation along strike. Proprietary strike-line seismic-reflection profiles cross three of the lateral ramps that were identified by using the surface criteria. The profiles confirm their presence and show their detailed nature in the subsurface. Like frontal ramps, lateral ramps are one of two possible consequences of fold-and-thrust-belt tectonics and are common elements in the Appalachian fold-and-thrust belt. A survey of other thrust belts in the United States and elsewhere strongly suggests that lateral ramps at depth can be identified by their surface effects. Lateral ramps probably are the result of thrust sheet motion caused by continued activation of ancient cratonic fracture systems. Such fractures localized the transform faults along which the continental segments adjusted during episodes of sea-floor spreading.
NASA Astrophysics Data System (ADS)
Harting, D. M.; Liang, Y.; Jachmich, S.; Koslowski, R.; Arnoux, G.; Devaux, S.; Eich, T.; Nardon, E.; Reiter, D.; Thomsen, H.; EFDA contributors, JET
2012-05-01
At JET the error field correction coils can be used to generate an n = 1 or n = 2 magnetic perturbation field (Liang et al 2007 Plasma Phys. Control. Fusion 49 B581). Various experiments at JET have already been carried out to investigate the mitigation of ELMs by resonant magnetic perturbations (RMPs) (Liang et al 2010 Nucl. Fusion 50 025013, Liang et al 2011 Nucl. Fusion 51 073001). However, the typical formation of a secondary strike point (strike point splitting) by RMPs observed in other machines (Jakubowski et al 2010 Contrib. Plasma Phys. 50 701-7, Jakubowski et al 2004 Nucl. Fusion 44 S1-11, Nardon et al 2011 J. Nucl. Mater. 415 S914-7, Eich et al 2003 Phys. Rev. Lett. 91 195003, Evans et al 2007 J. Nucl. Mater. 363-365 570-4, Evans et al 2005 J. Phys.: Conf. Ser. 7 174-90, Watkins et al 2009 J. Nucl. Mater. 390-391 839-42) has never been observed at JET before. In this work we will present discharges where for the first time a strike point splitting by RMPs at JET has been observed. We will show that in these particular cases the strike point splitting matches the vacuum edge magnetic field topology. This is done by comparing heat and particle flux profiles on the outer divertor plate with the magnetic footprint pattern obtained by field line tracing. Further the evolution of the strike point splitting during the ramp up phase of the perturbation field and during a q95-scan is investigated, and it will be shown that the spontaneous appearance of the strike point splitting is only related to some geometrical effects of the toroidal asymmetric magnetic topology.
Westphal, Rebecca E.; O'Malley, Donald M.
2013-01-01
At 5 days post-fertilization and 4 mm in length, zebrafish larvae are successful predators of mobile prey items. The tracking and capture of 200 μm long Paramecia requires efficient sensorimotor transformations and precise neural controls that activate axial musculature for orientation and propulsion, while coordinating jaw muscle activity to engulf them. Using high-speed imaging, we report striking changes across ontogeny in the kinematics, structure and efficacy of zebrafish feeding episodes. Most notably, the discrete tracking maneuvers used by larval fish (turns, forward swims) become fused with prey capture swims to form the continuous, fluid homing strikes of juvenile and adult zebrafish. Across this same developmental time frame, the duration of feeding episodes become much shorter, with strikes occurring at broader angles and from much greater distances than seen with larval zebrafish. Moreover, juveniles use a surprisingly diverse array of motor patterns that constitute a flexible predatory strategy. This enhances the ability of zebrafish to capture more mobile prey items such as Artemia. Visually-guided tracking is complemented by the mechanosensory lateral line system. Neomycin ablation of lateral line hair cells reduced the accuracy of strikes and overall feeding rates, especially when neomycin-treated larvae and juveniles were placed in the dark. Darkness by itself reduced the distance from which strikes were launched, as visualized by infrared imaging. Rapid growth and changing morphology, including ossification of skeletal elements and differentiation of control musculature, present challenges for sustaining and enhancing predatory capabilities. The concurrent expansion of the cerebellum and subpallium (an ancestral basal ganglia) may contribute to the emergence of juvenile homing strikes, whose ontogeny possibly mirrors a phylogenetic expansion of motor capabilities. PMID:23761739
Fatal lightning strikes in Malaysia.
Murty, O P; Kian, Chong Kah; Ari Husin, Mohammed Husrul; Nanta Kumar, Ranjeev Kumar; Mohammed Yusuf, Wan Yuhana W
2009-09-01
Lightning strike is a natural phenomenon with potentially devastating effects and represents one of the important causes of deaths from environmental phenomena. Almost every organ system may be affected as lightning current passes through the human body taking the shortest pathways between the contact points. A 10 years retrospective study (1996-2005) was conducted at University Hospital Kuala Lumpur (20 cases) also including cases during last 3 years from Hospital Tengku Ampuan Rahimah, Klang (7 cases) from the autopsy reports at Forensic Pathology Units of these 2 hospitals. Both these hospitals are attached to University of Malaya. There were 27 fatal cases of lightning strike with male preponderance(92.59%) and male to female ratio of 12.5:1. Majority of victims of lightning strike were from the age group between 30 and 39 years old. Most of the victims were foreign workers. Indonesians workers contributed to 59.26% of overall cases. Majority of them were construction workers who attributed i.e.11 of 27 cases (40.74%). Most of the victims were brought in dead (37.04%). In majority of the cases the lightning incidence occurred in the evenings, with the frequency of 15 of 27 cases (62.5%). The month of December represented with the highest number of cases (5 cases of 23 cases); 2004 had the highest incidence of lightning strike which was 5 (19.23%). Lightning strike incidence occurred when victims had taken shelter (25.9%) under trees or shades. Lightning strike in open areas occurred in 10 of 27 cases (37.0%). Head and neck were the most commonly affected sites with the incidence of 77.78% and 74% respectively in all the victims. Only 29.63% of the cases presented with ear bleeding.
Carvalho-Oliveira, R; Pozo, R M K; Lobo, D J A; Lichtenfels, A J F C; Martins-Junior, H A; Bustilho, J O W V; Saiki, M; Sato, I M; Saldiva, P H N
2005-05-01
In 2003, a bus strike paralyzed the fleet of buses in Sao Paulo, Brazil during 3 days, from 6 to 8 of April, the complete interruption of services being achieved on the 7th. We evaluated the effect of the absence of this source of pollution on the composition, mutagenicity, and toxicity of the fine particulate material collected during this period. Particles were sampled in glass fiber filters on days 7 and 15 of April of 2003 (strike and nonstrike days, respectively), using a high-volume sampler. Trace element determinations (As, Br, Co, Cl, Fe, La, Mn, Sb, Sc, and Th) of particulate material samples were carried out by neutron activation analysis. Sulfur determination was done by X-ray fluorescence analysis. The ratio between nonstrike/strike concentrations of hydrocarbons associated with automotive emissions (benzene, toluene, ethyl-benzene, and xylenes; BTEX) was determined by gas chromatography/mass spectrometry. Mutagenesis of testing solutions was determined by means of the Tradescantia micronucleus assay in early tetrads of Tradescantia pallida. The inhibition of mitosis of the cells of the primary meristema of the root tips of Allium cepa was used as an index of the toxicity. Fine particle trace element contents were lower during the strike. The concentrations of sulfur and BTEX were 50% and 39.3% lower, respectively, on the strike day. A significant (P=0.038) reduction of micronuclei induced by fine particles sampled during the strike was observed. No effect of the strike on toxicity was detected. These results indicate that a program aiming to reduce emissions of the bus fleet in our town may impact positively the air quality by reducing the mutagenic potential of ambient particles.
Surface-wave potential for triggering tectonic (nonvolcanic) tremor
Hill, D.P.
2010-01-01
Source processes commonly posed to explain instances of remote dynamic triggering of tectonic (nonvolcanic) tremor by surface waves include frictional failure and various modes of fluid activation. The relative potential for Love- and Rayleigh-wave dynamic stresses to trigger tectonic tremor through failure on critically stressed thrust and vertical strike-slip faults under the Coulomb-Griffith failure criteria as a function of incidence angle is anticorrelated over the 15- to 30-km-depth range that hosts tectonic tremor. Love-wave potential is high for strike-parallel incidence on low-angle reverse faults and null for strike-normal incidence; the opposite holds for Rayleigh waves. Love-wave potential is high for both strike-parallel and strike-normal incidence on vertical, strike-slip faults and minimal for ~45?? incidence angles. The opposite holds for Rayleigh waves. This pattern is consistent with documented instances of tremor triggered by Love waves incident on the Cascadia mega-thrust and the San Andreas fault (SAF) in central California resulting from shear failure on weak faults (apparent friction, ????? 0.2). However, documented instances of tremor triggered by surface waves with strike-parallel incidence along the Nankai megathrust beneath Shikoku, Japan, is associated primarily with Rayleigh waves. This is consistent with the tremor bursts resulting from mixed-mode failure (crack opening and shear failure) facilitated by near-lithostatic ambient pore pressure, low differential stress, with a moderate friction coefficient (?? ~ 0.6) on the Nankai subduction interface. Rayleigh-wave dilatational stress is relatively weak at tectonic tremor source depths and seems unlikely to contribute significantly to the triggering process, except perhaps for an indirect role on the SAF in sustaining tremor into the Rayleigh-wave coda that was initially triggered by Love waves.
Surface-wave potential for triggering tectonic (nonvolcanic) tremor-corrected
Hill, David P.
2012-01-01
Source processes commonly posed to explain instances of remote dynamic triggering of tectonic (nonvolcanic) tremor by surface waves include frictional failure and various modes of fluid activation. The relative potential for Love- and Rayleigh-wave dynamic stresses to trigger tectonic tremor through failure on critically stressed thrust and vertical strike-slip faults under the Coulomb-Griffith failure criteria as a function of incidence angle are anticorrelated over the 15- to 30-km-depth range that hosts tectonic tremor. Love-wave potential is high for strike-parallel incidence on low-angle reverse faults and null for strike-normal incidence; the opposite holds for Rayleigh waves. Love-wave potential is high for both strike-parallel and strike-normal incidence on vertical, strike-slip faults and minimal for ~45° incidence angles. The opposite holds for Rayleigh waves. This pattern is consistent with documented instances of tremor triggered by Love waves incident on the Cascadia megathrust and the San Andreas fault (SAF) in central California resulting from shear failure on weak faults (apparent friction is μ* ≤ 0:2). Documented instances of tremor triggered by surface waves with strike-parallel incidence along the Nankai megathrust beneath Shikoku, Japan, however, are associated primarily with Rayleigh waves. This is consistent with the tremor bursts resulting from mixed-mode failure (crack opening and shear failure) facilitated by near-lithostatic ambient pore pressure, low differential stress, with a moderate friction coefficient (μ ~ 0:6) on the Nankai subduction interface. Rayleigh-wave dilatational stress is relatively weak at tectonic tremor source depths and seems unlikely to contribute significantly to the triggering process, except perhaps for an indirect role on the SAF in sustaining tremor into the Rayleigh-wave coda that was initially triggered by Love waves.
Thornton, Vanessa; Hazell, Wayne
2008-10-01
To describe the response and analyse ED performance during a 5-day junior doctor strike. Data were collected via the patient information management computer system. Key performance indicators included percentage seen within maximum waiting times per triage category (TC), ED length of stay, emergency medicine patients who did not wait to be seen, hospital bed occupancy and access block percentage. Comparisons were made for the same 5 days before the strike (BS), during the strike (S) and after the strike. Total doctor's shifts BS were 78.66 with 25% of these shifts being Fellow of the Australasian College for Emergency Medicine (FACEM) shifts. FACEM shifts were more common during the S period at 75% (P < 0.001). Total attendances (BS 631 vs S 596, P = 0.22) and TC percentages (P-values for TC 1, 2, 3, 4, 5, respectively, 1.0, 0.55, 0.88, 0.97, 0.46) in the BS, S and after-the-strike periods were not significantly different. Despite fewer total doctor shifts, the FACEM predominant model of care during the strike resulted in better percentages seen within the maximum waiting times for TC3 (66%), TC4 (78%) and TC5 (86%) (all P < 0.001). There was a reduction in patients who did not wait to be seen (28 BS vs 5 S, P < 0.001), ED length of stay (admissions: BS 451 min vs S 258 min, P < 0.001; discharges: BS 233 min vs S 144 min, P < 0.02) and referrals to inpatient services (P = 0.02). This occurred with reduced bed point occupancy of 66% and a consequent reduction in access block. FACEM staffing and reduced access block were significant factors in improved ED performance.
Methods to enhance seismic faults and construct fault surfaces
NASA Astrophysics Data System (ADS)
Wu, Xinming; Zhu, Zhihui
2017-10-01
Faults are often apparent as reflector discontinuities in a seismic volume. Numerous types of fault attributes have been proposed to highlight fault positions from a seismic volume by measuring reflection discontinuities. These attribute volumes, however, can be sensitive to noise and stratigraphic features that are also apparent as discontinuities in a seismic volume. We propose a matched filtering method to enhance a precomputed fault attribute volume, and simultaneously estimate fault strikes and dips. In this method, a set of efficient 2D exponential filters, oriented by all possible combinations of strike and dip angles, are applied to the input attribute volume to find the maximum filtering responses at all samples in the volume. These maximum filtering responses are recorded to obtain the enhanced fault attribute volume while the corresponding strike and dip angles, that yield the maximum filtering responses, are recoded to obtain volumes of fault strikes and dips. By doing this, we assume that a fault surface is locally planar, and a 2D smoothing filter will yield a maximum response if the smoothing plane coincides with a local fault plane. With the enhanced fault attribute volume and the estimated fault strike and dip volumes, we then compute oriented fault samples on the ridges of the enhanced fault attribute volume, and each sample is oriented by the estimated fault strike and dip. Fault surfaces can be constructed by directly linking the oriented fault samples with consistent fault strikes and dips. For complicated cases with missing fault samples and noisy samples, we further propose to use a perceptual grouping method to infer fault surfaces that reasonably fit the positions and orientations of the fault samples. We apply these methods to 3D synthetic and real examples and successfully extract multiple intersecting fault surfaces and complete fault surfaces without holes.
Integrating the Land and Air Components in an Anti-Access/Area Denial Environment
2013-06-01
to his pursuit and bomber squadrons being already tasked to their limits, Fredendall retorted that he had lost 300 men due to enemy actions and the...190 Murray and Scales, The Iraq War, 173. 191 Author’s personal experience as a Close Air Support planner and Strike Package ...in the future the command and control structure will need to support air strike packages transitioning from interdiction and global strike missions to
Design of a Quasi-Passive Parallel Leg Exoskeleton to Augment Load Carrying for Walking
2005-08-01
cycle,’ which is time normalized. The following figure is a pictorial illustration of the gait cycle. The gait cycle begins with the heel strike ...Positive Power – Stabilization during heel strike . (H2) Negative Power – Body pendulums over the leg and stretches the quadriceps. (H3) Positive Power...Explanations: (K1) Negative Power – Knee braking/bending after heel strike . (K2) Positive Power – Knee straightening. (K3) Negligible Power
Conventional Prompt Global Strike and Long-Range Ballistic Missiles: Background and Issues
2013-04-26
developing scramjet — supersonic combustion ramjet—technologies that may contribute to the long-range strike mission in the future. In this type of vehicle ... vehicle that could deploy on a modified Peacekeeper land- based ballistic missile—a system known as the Conventional Strike Missile (CSM). In FY2008...into the Air Force CSM and two possible hypersonic glide vehicles . Congress appropriated $174.8 million for CPGS capability development in FY2012. DOD
Counter-Unmanned Aerial Vehicle Warfare: Kill Authorizations for the Carrier Strike Group
2016-06-10
COUNTER-UNMANNED AERIAL VEHICLE WARFARE: KILL AUTHORIZATIONS FOR THE CARRIER STRIKE GROUP A thesis presented to the Faculty...the Carrier Strike Group 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) LCDR Joshua C. Mattingly, U.S...including armed UAVs in an offensive role, but counter- UAV warfare is a new warfare area within the larger realm of air defense. Small Group 1 and 2
Warr, Bradley J; Fellin, Rebecca E; Sauer, Shane G; Goss, Donald L; Frykman, Peter N; Seay, Joseph F
2015-07-01
Characterize the distribution of foot-strike (FS) patterns in U.S. Army Soldiers and determine if FS patterns are related to self-reported running injuries and performance. 341 male Soldiers from a U.S. Army Combined Arms Battalion ran at their training pace for 100 meters, and FSs were recorded in the sagittal plane. Participants also completed a survey related to training habits, injury history, and run times. Two researchers classified FS patterns as heel strike (HS) or nonheel strike (NHS, combination of midfoot strike and forefoot strike patterns). Two clinicians classified the musculoskeletal injuries as acute or overuse. The relationship of FS type with two-mile run time and running-related injury was analyzed (p ≤ 0.05). The Soldiers predominately landed with an HS (87%) and only 13% were characterized as NHS. Running-related injury was similar between HS (50.3%) and NHS (55.6%) patterns (p = 0.51). There was no difference (p = 0.14) between overuse injury rates between an HS pattern (31.8%) and an NHS pattern (31.0%). Two-mile run times were also similar, with both groups averaging 14:48 minutes. Soldiers were mostly heel strikers (87%) in this U.S. Army Combined Arms Battalion. Neither FS pattern was advantageous for increased performance or decreased incidence of running-related injury. Reprint & Copyright © 2015 Association of Military Surgeons of the U.S.
Cooper, Danielle M; Leissring, Sarah K; Kernozek, Thomas W
2015-06-01
Claims of injury reduction related to barefoot running has resulted in interest from the running public; however, its risks are not well understood for those who typically wear cushioned footwear. Examine how plantar loading changes during barefoot running in a group of runners that ordinarily wear cushioned footwear and demonstrate a rearfoot strike pattern (RFSP) without cueing or feedback alter their foot strike pattern and plantar loading when asked to run barefoot at different speeds down a runway. Forty-one subjects ran barefoot at three different speeds across a pedography platform which collected plantar loading variables for 10 regions of the foot; data were analyzed using two-way mixed multivariate analysis of variance (MANOVA). A significant foot strike position (FSP)×speed interaction in each of the foot regions indicated that plantar loading differed based on FSP across the different speeds. The RFSP provided the highest total forces across the foot while the pressures displayed in subjects with a non-rearfoot strike pattern (NRFSP) was more similar between each of the metatarsals. The majority of subjects ran barefoot with a NRFSP and demonstrated lower total forces and more uniform force distribution across the metatarsal regions. This may have an influence in injuries sustained in barefoot running. Copyright © 2015 Elsevier Ltd. All rights reserved.
Yoshida, Naruto; Kunugi, Shun; Mashimo, Sonoko; Okuma, Yoshihiro; Masunari, Akihiko; Miyazaki, Shogo; Hisajima, Tatsuya; Miyakawa, Shumpei
2015-06-01
The purpose of this study is to examine the effects of different strike forms, during cutting, on knee joint angle and lower limb muscle activity. Surface electromyography was used to measure muscle activity in individuals performing cutting manoeuvres involving either rearfoot strikes (RFS) or forefoot strikes (FFS). Three-dimensional motion analysis was used to calculate changes in knee angles, during cutting, and to determine the relationship between muscle activity and knee joint angle. Force plates were synchronized with electromyography measurements to compare muscle activity immediately before and after foot strike. The valgus angle tends to be smaller during FFS cutting than during RFS cutting. Just prior to ground contact, biceps femoris, semitendinosus, and lateral head of the gastrocnemius muscle activities were significantly greater during FFS cutting than during RFS cutting; tibialis anterior muscle activity was greater during RFS cutting. Immediately after ground contact, biceps femoris and lateral head of the gastrocnemius muscle activities were significantly greater during FFS cutting than during RFS cutting; tibialis anterior muscle activity was significantly lower during FFS cutting. The results of the present study suggest that the hamstrings demonstrate greater activity, immediately after foot strike, during FFS cutting than during RFS cutting. Thus, FFS cutting may involve a lower risk of anterior cruciate ligament injury than does RFS cutting.
MARCHILDON, GREGORY P.; SCHRIJVERS, KLAARTJE
2011-01-01
Organised medicine in a number of advanced industrial countries resisted the post-war trend toward more state involvement in the funding and organisation of medical care. While there were eight doctors’ strikes during the peak of reform efforts in the 1960s, two of the most prolonged and bitter struggles took place in Canada and Belgium. This comparative analysis of the two strikes highlights the philosophy, motives, and strategies of organised medicine in resisting state-led reform efforts. Although historical and institutional contexts in the two countries differed, organised medicine in Canada and Belgium thought and responded in very similar ways to the perceived threat of medical insurance reform. While the perception of who won and who lost the respective doctors’ strikes differed, the ultimate impact on the trajectory of public healthcare on the medical profession was remarkably similar. In both countries, the strike would have a long-standing impact on future reform efforts, particularly efforts to reform physician remuneration in order to facilitate more effective primary healthcare. PMID:21461310
Foot speed, foot-strike and footwear: linking gait mechanics and running ground reaction forces.
Clark, Kenneth P; Ryan, Laurence J; Weyand, Peter G
2014-06-15
Running performance, energy requirements and musculoskeletal stresses are directly related to the action-reaction forces between the limb and the ground. For human runners, the force-time patterns from individual footfalls can vary considerably across speed, foot-strike and footwear conditions. Here, we used four human footfalls with distinctly different vertical force-time waveform patterns to evaluate whether a basic mechanical model might explain all of them. Our model partitions the body's total mass (1.0 Mb) into two invariant mass fractions (lower limb=0.08, remaining body mass=0.92) and allows the instantaneous collisional velocities of the former to vary. The best fits achieved (R(2) range=0.95-0.98, mean=0.97 ± 0.01) indicate that the model is capable of accounting for nearly all of the variability observed in the four waveform types tested: barefoot jog, rear-foot strike run, fore-foot strike run and fore-foot strike sprint. We conclude that different running ground reaction force-time patterns may have the same mechanical basis. © 2014. Published by The Company of Biologists Ltd.
Lightning attachment patterns and flight conditions for storm hazards, 1980
NASA Technical Reports Server (NTRS)
Fisher, B. D.; Keyser, G. L., Jr.; Deal, P. L.
1982-01-01
As part of the NASA Langley Research Center Storm Hazards Program, 69 thunderstorm pentrations were made in 1980 with an F-106B airplane in order to record direct strike lightning data and the associated flight conditions. Ground based weather radar measurements in conjunction with these penetrations were made by NOAA National Severe Storms Laboratory in Oklahoma and by NASA Wallops Flight Center in Virginia. In 1980, the airplane received 10 direct lightning strikes; in addition, lightning transient data were recorded from 6 nearby flashes. Following each flight, the airplane was thoroughly inspected for evidence of lightning attachment, and the individual lightning attachment points were plotted on isometric projections of the airplane to identify swept flash patterns. This report presents pilot descriptions of the direct strikes to the airplane, shows the strike attachment patterns that were found, and discusses the implications of the patterns with respect to aircraft protection design. The flight conditions are also included. Finally, the lightning strike scenarios for three U.S. Air Force F-106A airplanes which were struck during routine operations are given in the appendix to this paper.
Ervilha, Ulysses Fernandes; Mochizuki, Luis; Figueira, Aylton; Hamill, Joseph
2017-09-01
This study aimed to investigate the activation of lower limb muscles during barefoot and shod running with forefoot or rearfoot footfall patterns. Nine habitually shod runners were asked to run straight for 20 m at self-selected speed. Ground reaction forces and thigh and shank muscle surface electromyographic (EMG) were recorded. EMG outcomes (EMG intensity [iEMG], latency between muscle activation and ground reaction force, latency between muscle pairs and co-activation index between muscle pairs) were compared across condition (shod and barefoot), running cycle epochs (pre-strike, strike, propulsion) and footfall (rearfoot and forefoot) by ANOVA. Condition affected iEMG at pre-strike epoch. Forefoot and rearfoot strike patterns induced different EMG activation time patterns affecting co-activation index for pairs of thigh and shank muscles. All these timing changes suggest that wearing shoes or not is less important for muscle activation than the way runners strike the foot on the ground. In conclusion, the guidance for changing external forces applied on lower limbs should be pointed to the question of rearfoot or forefoot footfall patterns.
NASA Astrophysics Data System (ADS)
Sousasantos, Jonas; Sobral, José Humberto Andrade; Alam Kherani, Esfhan; Magalhães Fares Saba, Marcelo; Rodolfo de Campos, Diovane
2018-03-01
The vertical coupling between the troposphere and the ionosphere presents some remarkable features. Under intense tropospheric convection, gravity waves may be generated, and once they reach the ionosphere, these waves may seed instabilities and spread F and equatorial plasma bubble events may take place. Additionally, there is a close association between severe tropospheric convection and lightning strikes. In this work an investigation covering an equinox period (September-October) during the deep solar minimum (2009) presents the relation between lightning strike activity and spread F (equatorial plasma bubble) detected over a low-latitude Brazilian region. The results show a considerable correlation between these two phenomena. The common element in the center of this conformity seems to be the gravity waves. Once gravity waves and lightning strikes share the same source (intense tropospheric convection) and the effects of such gravity waves in the ionosphere include the seeding of instabilities according to the gravity waves magnitude, the monitoring of the lightning strike activity seems to offer some information about the subsequent development of spread F over the equatorial region.
Kinematics and Mechanics analysis of trap-jaw ant Odontomachus monticola
NASA Astrophysics Data System (ADS)
Hao, Wenteng; Yao, Guang; Zhang, Xiangyu; Zhang, Deyuan
2018-03-01
Trap-jaw ants of the genus Odontomachus exhibit spectacularly rapid predatory and fugitive strikes. In order to reveal the extraordinary impact resistance of the apical teeth material, we analyzed the kinematics and mechanics of the closing mandibles. Odontomachus monticola is an Odontomachus species and extensive in China. We video-recorded jaw-strikes to measure the closing velocity and acceleration. The experimental results showed that O. monticola’s mandibles closed at a highest velocity of 35.42 m/s and a highest acceleration of 750,000 m/s2 within an average duration of 0.16 ms. In addition, in order to measure the strike force, we developed an extraordinary measuring method with poly (vinylidene fluoride) (PVDF) piezoelectric film. First, the dynamic calibration of the PVDF piezoelectric film was conducted, then the calibrated piezoelectric film was struck by O. monticola. Finally, the mandible strike force was calculated according to the calibration result and the output signal. The measurements results demonstrated that the strike force ranges from 102.2 N to 235.2 N, which is impressive contrast with O. monticola’s body weight.
Structural Data for the Columbus Salt Marsh Geothermal Area - GIS Data
Faulds, James E.
2011-12-31
Shapefiles and spreadsheets of structural data, including attitudes of faults and strata and slip orientations of faults. - Detailed geologic mapping of ~30 km2 was completed in the vicinity of the Columbus Marsh geothermal field to obtain critical structural data that would elucidate the structural controls of this field. - Documenting E‐ to ENE‐striking left lateral faults and N‐ to NNE‐striking normal faults. - Some faults cut Quaternary basalts. - This field appears to occupy a displacement transfer zone near the eastern end of a system of left‐lateral faults. ENE‐striking sinistral faults diffuse into a system of N‐ to NNE‐striking normal faults within the displacement transfer zone. - Columbus Marsh therefore corresponds to an area of enhanced extension and contains a nexus of fault intersections, both conducive for geothermal activity.
Strike-slip faulting, wrinkle ridges, and time variable stress states in the Coprates Region of Mars
NASA Technical Reports Server (NTRS)
Schultz, Richard A.
1990-01-01
The existence of strike-slip faults was recently documented in two locations on Mars. Two clear examples are reviewed located southeast of Valles Marineris and preliminary evidence is presented for more widespread strike-slip deformation elsewhere in Coprates. The first two examples show that strike-slip faulting occurred in a broad zone east of the Coprates Rise spanning approximately 400 km east-west by perhaps 1000 km north-south. The last example suggests that the growth of major wrinkle ridges throughout Coprates may have been influenced by horizontally directed shear stresses and that more than one generation of ridges was produced. Thus, 'compressional' deformation of ridged plains south of Valles Marineris was spatially heterogeneous and a temporal change in stress may have been involved.
After the strike: using facilitation in a residency training program.
Andres, D; Hamoline, D; Sanders, M; Anderson, J
1998-03-10
Methods of alternative dispute resolution, including facilitation, can be used to identify and resolve areas of conflict. Facilitation was used by the University of Saskatchewan's Department of Family Medicine (Saskatoon division) after the strike by residents in July and August 1995 so as to allow optimal use of the remaining educational time. Through facilitation, experiences of the strike and areas of potential conflict were explored. Participants had a broad range of responses to the strike. Specific coping strategies were developed to deal with identified concerns. Although outcomes were not measured formally, levels of trust improved and collegial relationships were restored. Because so many changes occur in health care and medical education, conflict inevitably arises. Facilitation offers one way of dealing with change constructively, thereby making possible the optimal use of educational time.
NASA Technical Reports Server (NTRS)
Adams, Marc A.; Zwissler, James G.; Hayes, Charles; Fabensky, Beth; Cornelison, Charles; Alexander, Lesley; Bishop, Karen
2005-01-01
A new technology is being developed that can protect spacecraft and satellite components against damage from meteoroid strikes and control the thermal environment of the protected components. This technology, called Foam Core Shield (FCS) systems, has the potential to replace the multi-layer insulation blankets (MLI) that have been used on spacecraft for decades. In order to be an attractive candidate for replacing MLI, FCS systems should not only provide superior protection against meteoroid strikes but also provide an equal or superior ability to control the temperature of the protected component. Properly designed FCS systems can provide these principal functions, meteoroid strike protection and thermal control, with lower system mass and a smaller system envelope than ML.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Deng, Z.; Carlson, T. J.; Ploskey, G. R.
2005-11-01
Bio-indexing of hydro turbines has been identified as an important means to optimize passage conditions for fish by identifying operations for existing and new design turbines that minimize the probability of injury. Cost-effective implementation of bio-indexing requires the use of tools such as numerical and physical turbine models to generate hypotheses for turbine operations that can be tested at prototype scales using live fish. Blade strike has been proposed as an index variable for the biological performance of turbines. Report reviews an evaluation of the use of numerical blade-strike models as a means with which to predict the probability ofmore » blade strike and injury of juvenile salmon smolt passing through large Kaplan turbines on the mainstem Columbia River.« less
Hagstrum, J.T.; Gans, P.B.
1989-01-01
The Oligocene Kalamazoo Tuff (???35 Ma) was sampled for paleomagnetic analysis across a 100-km-wide zone of highly extended crust in east central Nevada to estimate between-site vertical axis rotations and thus the relative importance of strike-slip faulting to the mechanism of extension. The tilt-corrected data, with sources of error reduced or eliminated, exhibit a 28?? ?? 12?? clockwise rotation of the Schell Creek Range relative to the Kern Mountains region. This rotation implies differential extension accommodated by strike-slip faulting or N-S shortening. The paleomagnetic results also suggest that large changes in strike of layered units near faults with presumed strike-slip movement need not be the result of oroclinal bending, but could result from superimposed sets of orthogonal normal faults. -from Authors
NASA Astrophysics Data System (ADS)
Bellier, Olivier; Zoback, Mary Lou
1995-06-01
The NW to north-trending Walker Lane zone (WLZ) is located along the western boundary of the northern Basin and Range province with the Sierra Nevada. This zone is distinguished from the surrounding Basin and Range province on the basis of irregular topography and evidence for both normal and strike-slip Holocene faulting. Inversion of slip vectors from active faults, historic fault offsets, and earthquake focal mechanisms indicate two distinct Quaternary stress regimes within the WLZ, both of which are characterized by a consistent WNW σ3 axis; these are a normal faulting regime with a mean σ3 axis of N85°±9°W and a mean stress ratio (R value) (R=(σ2-σ1)/(σ3-σ1)) of 0.63-0.74 and a younger strike-slip faulting regime with a similar mean σ3 axis (N65° - 70°W) and R values ranging between ˜ 0.1 and 0.2. This younger regime is compatible with historic fault offsets and earthquake focal mechanisms. Both the extensional and strike-slip stress regimes reactivated inherited Mesozoic and Cenozoic structures and also produced new faults. The present-day strike-slip stress regime has produced strike-slip, normal oblique-slip, and normal dip-slip historic faulting. Previous workers have explained the complex interaction of active strike-slip, oblique, and normal faulting in the WLZ as a simple consequence of a single stress state with a consistent WNW σ3 axis and transitional between strike-slip and normal faulting (maximum horizontal stress approximately equal to vertical stress, or R ≈ 0 in both regimes) with minor local fluctuations. The slip data reported here support previous results from Owens Valley that suggest deformation within temporally distinct normal and strike-slip faulting stress regimes with a roughly constant WNW trending σ3 axis (Zoback, 1989). A recent change from a normal faulting to a strike-slip faulting stress regime is indicated by the crosscutting striae on faults in basalts <300,000 years old and is consistent with the dominantly strike-slip earthquake focal mechanisms and the youngest striae observed on faults in Plio-Quaternary deposits. Geologic control on the timing of the change is poor; it is impossible to determine if there has been a single recent absolute change or if there is, rather, an alternating or cyclical variation in stress magnitudes. Our slip data, in particular, the cross-cutting normal and strike-slip striae on the same fault plane, are inconsistent with postulated simple strain partitioning of deformation within a single regional stress field suggested for the WLZ by Wesnousky and Jones [1994]. The location of the WLZ between the deep-seated regional extension of the Basin and Range and the right-lateral strike-slip regional tectonics of the San Andreas fault zone is probably responsible for the complex interaction of tectonic regimes in this transition zone. In early to mid-Tertiary time the WLZ appears to have had a similarly complex deformational history, in this case as a back arc or intra-arc region, accommodating at least part of the right-lateral component of oblique convergence as well as a component of extension.
Hansen, Bruce P.; Stone, Janet Radway; Lane, John W.
1999-01-01
Surface and borehole geophysical methods were used to determine fracture orientation in crystalline bedrock at the Eastern Surplus Superfund Site in Meddybemps, Maine. Fracture-orientation information is needed to address concerns about the fate of contaminants in ground water at the site. Azimuthal square-array resistivity surveys were conducted at 3 locations at the site, borehole-acoustic televiewer and borehole-video logs were collected in 10 wells, and single-hole directional radar surveys were conducted in 9 wells. Borehole-video logs were used to supplement the results of other geophysical techniques and are not described in this report. Analysis of azimuthal square-array resistivity data indicated that high-angle fracturing generally strikes northeast-southwest at the three locations. Borehole-acoustic televiewer logs detected one prominent low-angle and two prominent high-angle fracture sets. The low-angle fractures strike generally north-northeast and dip about 20 degrees west-northwest. One high-angle fracture set strikes north-northeast and dips east-southeast; the other high-angle set strikes east-northeast and dips south-southeast. Single-hole directional radar surveys identified two prominent fracture sets: a low-angle set striking north-northeast, dipping west-northwest; and a high-angle fracture set striking north-northeast, dipping east-southeast. Two additional high-angle fracture sets are defined weakly, one striking east-west, dipping north; and a second striking east-west, dipping south. Integrated results from all of the geophysical surveys indicate the presence of three primary fracture sets. A low-angle set strikes north-northeast and dips west-northwest. Two high-angle sets strike north-northeast and east-northeast and dip east-southeast and south-southeast. Statistical correction of the fracture data for orientation bias indicates that high-angle fractures are more numerous than observed in the data but are still less numerous than the low-angle fractures. The orientation and distribution of water-yielding fractures sets were determined by correlating the fracture data from this study with previously collected borehole-flowmeter data. The water-yielding fractures are generally within the three prominent fracture sets observed for the total fracture population. The low-angle water-yielding fractures primarily strike north-northeast to west-northwest and dip west-northwest to south-southwest. Most of the high-angle water-yielding fractures strike either north-northeast or east-west and dip east-southeast or south. The spacing between water-yielding fractures varies but the probable average spacing is estimated to be 30 feet for low-angle fractures; 27 feet for the east-southeast dipping, high-angle fractures; and 43 feet for the south-southeast dipping, high-angle fractures. The median estimated apparent transmissivity of individual water-yielding fractures or fracture zones was 0.3 feet squared per day and ranged from 0.01 to 382 feet squared per day. Ninety-five percent of the water-yielding fractures or fracture zones had an estimated apparent transmissivity of 19.5 feet squared per day or less. The orientation, spacing, and hydraulic properties of water-yielding fractures identified during this study can be used to help estimate recharge, flow, and discharge of ground water contaminants. High-angle fractures provide vertical pathways for ground water to enter the bedrock, interconnections between low-angle fractures, and, subsequently, pathways for water flow within the bedrock along fracture planes. Low-angle fractures may allow horizontal ground-water flow in all directions. The orientation of fracturing and the hydraulic properties of each fracture set strongly affect changes in ground-water flow under stress (pumping) conditions.
NASA Astrophysics Data System (ADS)
Lee, J.; Stockli, D.; Gosse, J.
2007-12-01
Two different mechanisms have been proposed for fault slip transfer between the subparallel NW-striking dextral- slip faults that dominant the Eastern California Shear Zone (ECSZ)-Walker Lane Belt (WLB). In the northern WLB, domains of sinistral-slip along NE-striking faults and clockwise block rotation within a zone of distributed deformation accommodated NW-dextral shear. A somewhat modified version of this mechanism was also proposed for the Mina deflection, southern WLB, whereby NE-striking sinistral faults formed as conjugate faults to the primary zone of NW-dextral shear; clockwise rotation of the blocks bounding the sinistral faults accommodated dextral slip. In contrast, in the northern ECSZ and Mina deflection, domains of NE-striking pure dip-slip normal faults, bounded by NW-striking dextral-slip faults, exhibited no rotation; the proposed mechanism of slip transfer was one of right-stepping, high angle normal faults in which the magnitude of extension was proportional to the amount of strike-slip motion transferred. New geologic mapping, tectonic geomorphologic, and geochronologic data from the Queen Valley area, southern Mina deflection constrain Pliocene to late Quaternary fault geometries, slip orientations, slip magnitudes, and slip rates that bear on the mechanism of fault slip transfer from the relatively narrow northern ECSZ to the broad deformation zone that defines the Mina deflection. Four different fault types and orientations cut across the Queen Valley area: (1) The NE-striking normal-slip Queen Valley fault; (2) NE-striking sinistral faults; (3) the NW-striking dextral Coyote Springs fault, which merges into (4) a set of EW-striking thrust faults. (U-Th)/He apatite and cosmogenic radionuclide data, combined with magnitude of fault offset measurements, indicate a Pliocene to late Pleistocene horizontal extension rate of 0.2-0.3 mm/yr across the Queen Valley fault. Our results, combined with published slip rates for the dextral White Mountain fault zone (0.3-0.8 mm/yr) and the eastern sinistral Coaldale fault (0.4 mm/yr) suggest that transfer of dextral slip from the narrow White Mountains fault zone is explained best by a simple shear couple whereby slip is partitioned into three different components: horizontal extension along the Queen Valley fault, dominantly dextral slip along the Coyote Springs fault, and dominantly sinistral slip along the Coaldale fault. A velocity vector diagram illustrating fault slip partitioning predicts contraction rates of <0.1 to 0.5 mm/yr across the Coyote Springs and western Coaldale faults. The predicted long-term contraction across the Mina deflection is consistent with present-day GPS data.
Basement-driven strike-slip deformation involving a salt-stock canopy system
NASA Astrophysics Data System (ADS)
Dooley, Tim; Jackson, Martin; Hudec, Mike
2016-04-01
NW-striking basement-involved strike-slip zones have been reported or inferred from the northern Gulf of Mexico (GoM). This interpretation is uncertain, because the effects of strike-slip deformation are commonly difficult to recognize in cross sections. Recognition is doubly difficult if the strike-slip zone passes through a diapir field that complicates deformation, and an associated salt canopy that partially decouples shallow deformation from deep deformation. We use physical models to explore the effects of strike-slip deformation above and below a salt-stock canopy system. Canopies of varying maturity grew from a series of 14 feeders/diapirs located on and off the axis of a dextral basement fault. Strike-slip deformation styles in the overburden vary significantly depending on: (1) the location of the diapirs with respect to the basement fault trace, and; (2) the continuity of the canopy system. On-axis diapirs (where the diapirs lie directly above the basement fault) are typically strongly deformed and pinched shut at depth to form sharp S-shapes, whereas their shallow deformation style is that of a open-S-shaped pop-up structure in a restraining bend. The narrow diapir stem acts as a shear zone at depth. Pull-apart structures form between diapirs that are arranged in a right-stepping array tangental to the basement fault trace. These grade along strike into narrow negative flower structures. Off-axis diapirs (diapirs laterally offset from the basement fault but close enough to participate in the deformation) form zones of distributed deformation in the form of arrays of oblique faults (R shears) that converge along strike onto the narrower deformation zones associated with on-axis diapirs. Above an immature, or patchy, canopy system the strike-slip structures closely match sub canopy structures, with the exception of wrench fold formation where the supracanopy roof is thin. In contrast, the surface structures above a mature canopy system consist of a broad zone of PDZ-parallel faults and high-angle wrench folds, strongly decoupled from the subcanopy structure. The exception to this is where there are gaps (windows) in the canopy, allowing coupling to the deeper deformation field. In this mature canopy open-S planforms are muted as deformation is spread over a broader area of coalesced salt sheets, except at the canopy edge and where the supracanopy roof is thin. Supracanopy structures are also influenced by the sutures between the individual salt sheets. Results from this set of analog models are potentially useful as predictive tools to understand the origin and geometry of structures in areas where subsurface data is scarce or data quality is poor.
High Energy Laser on the Joint Strike Fighter: A Reality in 2025?
2007-02-26
10 October 2006. 19. Siegman , A.E., Nemes, G., Serna, J. “How to (Maybe) Measure Laser Beam Quality,” in DPSS (Diode Pumped Solid State) Lasers ...AIR WAR COLLEGE AIR UNIVERSITY HIGH ENERGY LASER ON THE JOINT STRIKE FIGHTER A REALITY IN 2025? by Jeffrey A. Hausmann, Lt Col, USAF A...00-00-2007 to 00-00-2007 4. TITLE AND SUBTITLE High Energy Laser on the Joint Strike Fighter a Reality in 2025? 5a. CONTRACT NUMBER 5b. GRANT
Army Logistician. Volume 33, Issue 5, September-October 2001
2001-10-01
vehicle, and a first- strike ration that pro- vides an eat-out-of-hand capability for use during the initial stages of deployment, providing increased carbo...battle. On 9 September, a portion of the German 8th Army, striking though the Masurian Lakes region, severed the already anemic Rus- sian supply and...as the ability to “ strike the enemy at a time or place or in a manner for which he is unprepared.” Surprise can decisively shift the bal- ance of
The Great Green Fleet: The U.S. Navy and Fossil-Fuel Alternatives
2011-01-01
Tennessee at Chattanooga. She has served as a member of the Bataan Expeditionary Strike Group and U.S. Joint Forces Com- mand, completing deployments to...excess energy to the civilian grid. Third, by 2012 the Navy is to have developed a “green” strike group, made up of nuclear- powered carriers, hybrid...first strike group of a future “green fleet.” Fourth, by 2015 the Navy is to cut by half the use of petroleum in its fifty-thousand-vehicle fleet of
2016-11-01
Strike ( Malaysia ) Garuda Shield (Indonesia) Orient Shield (Japan) 15-1 Jan. – May 2015 2-25 Stryker BCT ~880 personnel Cobra Gold (Thailand) Foal...Keris Strike ( Malaysia ) 15-3 June-July, Aug. – Nov. 2015 1-25 Stryker BCT ~420 personnel Khan Quest (Mongolia) Orient Shield (Japan) Hoguk...Strike ( Malaysia ) Source: GAO analysis of U.S. Army Pacific data. | GAO-17-126 aIn addition to the brigades identified here, other units and personnel
9th Annual Systems Engineering Conference: Volume-1 Monday Tutorial
2006-10-26
Joint Integrating Concepts (JIC) • Forceable Entry Ops • Undersea Superiority • Global Strike Ops • Sea-Basing Ops • Air & Missile Defense • JC2 • Joint...Forceable Entry Ops o Undersea Superiority o Global Strike Ops o Sea-Basing Ops o Air & Missile Defense o JC2 o Joint Logistics Includes an illustrative... Undersea Superiority • Global Strike Ops • Sea-Basing Ops • Air & Missile Defense • JC2 • Joint Logistics Universal Joint Task List (UJTL) • Strategic
Detecting Gait Asymmetry with Wearable Accelerometers
2015-03-18
swing time to stride duration is referred to as swing factor [24]. Some features used in the past relate to the gait subphases: the heel - strike , when the...used in the past include the peaks of the impulse of the heel - strike [28] and toe-off force and the integral of the force over the course of the...with high acceleration and high jerk. Heel - strike and toe-off times are determined by extending outward from the identified stance time into areas of
Assessing the Role of Surgical Strike Operations in Support of a Special Warfare Campaign
2017-06-09
16 Surgical Strike Management and Integration ............................................................... 19 Summary...Integration and Management .................................................................................... 37 Case Study 2 VSO in Kunar Province...Effectiveness ............................................................................................................. 48 Integration and Management
Analytic Study of Three-Dimensional Rupture Propagation in Strike-Slip Faulting with Analogue Models
NASA Astrophysics Data System (ADS)
Chan, Pei-Chen; Chu, Sheng-Shin; Lin, Ming-Lang
2014-05-01
Strike-slip faults are high angle (or nearly vertical) fractures where the blocks have moved along strike way (nearly horizontal). Overburden soil profiles across main faults of Strike-slip faults have revealed the palm and tulip structure characteristics. McCalpin (2005) has trace rupture propagation on overburden soil surface. In this study, we used different offset of slip sandbox model profiles to study the evolution of three-dimensional rupture propagation by strike -slip faulting. In strike-slip faults model, type of rupture propagation and width of shear zone (W) are primary affecting by depth of overburden layer (H), distances of fault slip (Sy). There are few research to trace of three-dimensional rupture behavior and propagation. Therefore, in this simplified sandbox model, investigate rupture propagation and shear zone with profiles across main faults when formation are affecting by depth of overburden layer and distances of fault slip. The investigators at the model included width of shear zone, length of rupture (L), angle of rupture (θ) and space of rupture. The surface results was follow the literature that the evolution sequence of failure envelope was R-faults, P-faults and Y-faults which are parallel to the basement fault. Comparison surface and profiles structure which were curved faces and cross each other to define 3-D rupture and width of shear zone. We found that an increase in fault slip could result in a greater width of shear zone, and proposed a W/H versus Sy/H relationship. Deformation of shear zone showed a similar trend as in the literature that the increase of fault slip resulted in the increase of W, however, the increasing trend became opposite after a peak (when Sy/H was 1) value of W was reached (small than 1.5). The results showed that the W width is limited at a constant value in 3-D models by strike-slip faulting. In conclusion, this study helps evaluate the extensions of the shear zone influenced regions for strike-slip faults.
NASA Astrophysics Data System (ADS)
Lavier, L. L.; Bennett, R. A.; Anderson, M. L.; Matti, J. C.
2005-05-01
Recent displacement rate and geodetic data on the San Andreas, San Jacinto and eastern California shear zone suggest that changes in the geometry and/or the magnitude of the applied forces on the crust (e.g., a general or local change in fault strike relative to plate motion) can generate strain repartitioning within the crust on time scales of millions to thousands of years. The rates over which this repartitioning takes place in response to changing forces are controlled by the rheological evolution of the lithosphere. We investigate the implications of observed fault displacement histories for the rheology of the lithosphere using 2.5 D numerical experiments of deformation in an analogue system. The numerical technique used allows for the spontaneous formation of elastoplastic shear zones and flow in a Maxwell viscoelastic lower crust. The results show that when a strike slip fault is rotated to strike obliquely to the direction of relative plate motion it causes changes in bending and frictional stresses due to the formation of topography. To accommodate these changes, a conjugate system of oblique-striking strike slip faults develops. The total displacement is then slowly distributed over the new fault system on the time scale of mountain building (i.e. million of years). The rate of change is dependent on the strength of the lithosphere as well as the amount of obliquity applied on the initial strike-slip fault. In other numerical experiments we show that in a system of multiple strike-slip fault zones, displacement rate changes can occur over a time scale of about 100 kyr. This time scale corresponds to the Maxwell time at the brittle ductile transition (BDT). In such a system the lithospheric displacement is alternatively distributed (over 100 kyr) in clusters localized in lower crustal channels and over strike-slip fault zones. We show that the clustering time scale is controlled by the ratio of upper to lower crustal strength. This incomplete exercise shows how displacement rates data sets spanning thousands to millions of years can be used to constrain numerical experiments of lithospheric deformation and, in doing so, place new constraints on the rheology of the lithosphere.
NASA Astrophysics Data System (ADS)
Sirovich, L.; Pettenati, F.
2007-05-01
Using geophysical inversion to discover the fault source of a blind earthquake, that took place before the invention of the seismograph, seemed impossible. We demonstrated that sometimes it is possible using our simplified KF model (Sirovich, 1996) through automatic genetic inversion (Gentile et al., 2004 in BSSA; Sirovich and Pettenati, 2004 in JGR), and determined it conclusively by treating the Coalinga 1983, Loma Prieta 1989, and Northridge 1994 earthquakes (Pettenati and Sirovich, 2007 in BSSA). KF is able to simulate the body-wave radiation from a linear source, and eleven source parameters are retrieved: the three nucleation coordinates, the fault-plane solution, the seismic moment, the rupture velocities and lengths along-strike and anti-strike, the shear wave velocity in the half-space. To find the minima on the hypersurface of the residuals in the multi-parameter model space, we use a genetic process with niching since we have already shown that the problem is bimodal for pure dip-slip mechanisms. The objective function of the nonlinear inversion is the sum of the squared residuals (calculated-minus-observed intensity at all sites). Here, we use the very good intensity data provided in the MCS scale by the INGV of Italy for the M 6.9 earthquake of Feb. 5, 1783 (see the Italian intensity data bank on http:emidius.mi.ingv.it/DOM/consultazione.html). The data of 1783 were created by seismologists and historians who interpreted the reports of the time and many other historical sources. Given the limitations of the KF approach, we limited our inversion to a square area of 200 by 200 km around the most heavily damaged zone. 341 surveyed towns and hamlets received intensity degrees by INGV (we discarded 6 of them as statistical outliers according to the classical Chauvenet method). Thus, 335 data were inverted. The match between experimental and synthetic isoseismals is really noteworthy. The found mechanism is almost pure dip-slip and, thus, the problem is bimodal. In fact, two source models score almost the same objective function, and they coincide with the auxiliary planes of the same solution. The best source is: nucleation latitude [degrees] 38.28, longitude 15.95, depth 13.1 km; strike angle 210, dip 31, rake 269(±180); seismic moment 2.7 * 10e19 Nm, 3.1 km/s rupture velocity along-strike (3.3 anti-strike), 22.3 km rupture length along-strike (20.7 anti-strike), 3.9 km/s shear wave velocity in the half-space. The second solution, having the same nucleation coordinates and a one-point difference in the objective function (117 against 116) is: strike angle 30, dip 60, rake 270(±180); seismic moment 2.6 * 10e19 Nm, 3.3 km/s rupture velocity along-strike (3.0 anti-strike), 19.4 km rupture length along-strike (21.9 anti-strike), 3.9 km/s shear wave velocity in the half-space. Note the symmetry with the former solution. In other words, we find one fault source having a low-angle dip toward the Tyrrhenian Sea; its virtual intersection with the topographical surface should be found close to the Jonian coast. On the contrary, its symmetric solution strikes SW, has a high-angle dip toward the Jonian Sea, and the fault should outcrop close to the Tyrrhenian coast. Both sources are compatible with the orientation of the principal tectonic structures in the area, however. The final choice between them will hopefully come from tectonic interpretation. This kind of study seems especially promising for southern Europe where a lot of documents on seismic damage caused by old earthquakes exist.
Yager, Richard M.; Southworth, Scott C.; Voss, Clifford I.
2008-01-01
Ground-water flow was simulated using variable-direction anisotropy in hydraulic conductivity to represent the folded, fractured sedimentary rocks that underlie the Shenandoah Valley in Virginia and West Virginia. The anisotropy is a consequence of the orientations of fractures that provide preferential flow paths through the rock, such that the direction of maximum hydraulic conductivity is oriented within bedding planes, which generally strike N30 deg E; the direction of minimum hydraulic conductivity is perpendicular to the bedding. The finite-element model SUTRA was used to specify variable directions of the hydraulic-conductivity tensor in order to represent changes in the strike and dip of the bedding throughout the valley. The folded rocks in the valley are collectively referred to as the Massanutten synclinorium, which contains about a 5-km thick section of clastic and carbonate rocks. For the model, the bedrock was divided into four units: a 300-m thick top unit with 10 equally spaced layers through which most ground water is assumed to flow, and three lower units each containing 5 layers of increasing thickness that correspond to the three major rock units in the valley: clastic, carbonate and metamorphic rocks. A separate zone in the carbonate rocks that is overlain by colluvial gravel - called the western-toe carbonate unit - was also distinguished. Hydraulic-conductivity values were estimated through model calibration for each of the four rock units, using data from 354 wells and 23 streamflow-gaging stations. Conductivity tensors for metamorphic and western-toe carbonate rocks were assumed to be isotropic, while conductivity tensors for carbonate and clastic rocks were assumed to be anisotropic. The directions of the conductivity tensor for carbonate and clastic rocks were interpolated for each mesh element from a stack of 'form surfaces' that provided a three-dimensional representation of bedrock structure. Model simulations were run with (1) variable strike and dip, in which conductivity tensors were aligned with the strike and dip of the bedding, and (2) uniform strike in which conductivity tensors were assumed to be horizontally isotropic with the maximum conductivity direction parallel to the N30 deg E axis of the valley and the minimum conductivity direction perpendicular to the horizontal plane. Simulated flow penetrated deeper into the aquifer system with the uniform-strike tensor than with the variable-strike-and-dip tensor. Sensitivity analyses suggest that additional information on recharge rates would increase confidence in the estimated parameter values. Two applications of the model were conducted - the first, to determine depth of recent ground-water flow by simulating the distribution of ground-water ages, showed that most shallow ground water is less than 10 years old. Ground-water age distributions computed by variable-strike-and-dip and uniform-strike models were similar, but differed beneath Massanutten Mountain in the center of the valley. The variable-strike-and-dip model simulated flow from west to east parallel to the bedding of the carbonate rocks beneath Massanutten Mountain, while the uniform-strike model, in which flow was largely controlled by topography, simulated this same area as an east-west ground-water divide. The second application, which delineated capture zones for selected well fields in the valley, showed that capture zones delineated with both models were similar in plan view, but differed in vertical extent. Capture zones simulated by the variable-strike-and-dip model extended downdip with the bedding of carbonate rock and were relatively shallow, while those simulated by the uniform-strike model extended to the bottom of the flow system, which is unrealistic. These results suggest that simulations of ground-water flow through folded fractured rock can be constructed using SUTRA to represent variable orientations of the hydraulic-conductivity tensor and produce a
28 CFR 549.66 - Release from treatment.
Code of Federal Regulations, 2010 CFR
2010-07-01
... MEDICAL SERVICES Hunger Strikes, Inmate § 549.66 Release from treatment. Only the physician may order that an inmate be released from hunger strike evaluation and treatment. This order shall be documented in...
28 CFR 549.60 - Purpose and scope.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Hunger Strikes, Inmate § 549.60 Purpose and scope. The Bureau of Prisons provides guidelines for the medical and administrative management of inmates who engage in hunger strikes. It is the responsibility of...
28 CFR 549.62 - Initial referral.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Hunger Strikes, Inmate § 549.62 Initial referral. (a) Staff shall refer an inmate who is observed to be on a hunger strike to medical or mental health staff for evaluation and, when appropriate, for...
37 CFR 1.125 - Substitute specification.
Code of Federal Regulations, 2010 CFR
2010-07-01
... text of any deleted matter must be shown by strike-through except that double brackets placed before.... The text of any deleted subject matter must be shown by being placed within double brackets if strike...
Feature Hepatitis: Hepatitis Can Strike Anyone
... Navigation Bar Home Current Issue Past Issues Feature Hepatitis Hepatitis Can Strike Anyone Past Issues / Spring 2009 Table ... from all walks of life are affected by hepatitis, especially hepatitis C, the most common form of ...
NASA Technical Reports Server (NTRS)
Burns, Lee; Decker, Ryan
2004-01-01
Lightning strike location and peak current are monitored operationally in the Kennedy Space Center (KSC)/Cape Canaveral Air Force Station (CCAFS) area by the Cloud to Ground Lightning Surveillance System (CGLSS). The present study compiles ten years of CGLSS data into a climatological database of all strikes recorded within a 20-mile radius of space shuttle launch platform LP39A, which serves as a convenient central point. The period of record (POR) for the database runs from January 1, 1993 to December 31, 2002. Histograms and cumulative probability curves are produced to determine the distribution of occurrence rates for the spectrum of strike intensities (given in kA). Further analysis of the database provides a description of both seasonal and interannual variations in the lightning distribution.
Investigation on Improvements in Lightning Retest Criteria for Spacecraft
NASA Technical Reports Server (NTRS)
Terseck, Alex; Trout, Dawn
2016-01-01
Spacecraft are generally protected from a direct strike by launch the vehicle and ground structures, but protocols to evaluate the impact of nearby strikes are not consistent. Often spacecraft rely on the launch vehicle constraints to trigger a retest, but launch vehicles can typically evaluate the impact of a strike within minutes while spacecraft evaluation times can be on the order of hours or even days. For launches at the Kennedy Space Center where lightning activity is among the highest in the United States, this evaluation related delay could be costly with the possibility of missing the launch window altogether. This paper evaluated available data from local lightning measurements systems and computer simulations to predict the coupled effect from various nearby strikes onto a typical payload umbilical. Recommendations are provided to reduce the typical trigger criteria and costly delays.
Strike-slip faults in the Moroccan Rif: Their geophysical signatures and hydrocarbon potential
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jobidon, G.P.; Dakki, M.
1994-12-31
The Rif Domain in Northern Morocco includes major movements along left-lateral strike-slips faults that created various structures and influenced depositional systems. The major ones are the Jebha fault in the Rif`s northwest area, and the Nekkor fault that extends southwesterly from the Mediterranean sea toward the Meseta. Although identified by surface geology in the east, the western extent of the faults is ambiguous. Detail interpretation of gravity and magnetic maps provide a better definition of their locations and related structures. The Rif`s geology is a mirror image of the right-lateral strike-slip fault system of Venezuela and Trinidad. Most features associatedmore » with the Rif`s strike-slip faults have not been explored to data and hydrocarbon potential remains a good possibility.« less
After the strike: using facilitation in a residency training program
Andres, D; Hamoline, D; Sanders, M; Anderson, J
1998-01-01
Methods of alternative dispute resolution, including facilitation, can be used to identify and resolve areas of conflict. Facilitation was used by the University of Saskatchewan's Department of Family Medicine (Saskatoon division) after the strike by residents in July and August 1995 so as to allow optimal use of the remaining educational time. Through facilitation, experiences of the strike and areas of potential conflict were explored. Participants had a broad range of responses to the strike. Specific coping strategies were developed to deal with identified concerns. Although outcomes were not measured formally, levels of trust improved and collegial relationships were restored. Because so many changes occur in health care and medical education, conflict inevitably arises. Facilitation offers one way of dealing with change constructively, thereby making possible the optimal use of educational time. PMID:9526479
Effect of lightning strike on bromine intercalated graphite fiber/epoxy composites
NASA Technical Reports Server (NTRS)
Gaier, James R.; Slabe, Melissa E.; Brink, Norman O.
1991-01-01
Laminar composites were fabricated from pristine and bromine intercalated pitch based graphite fibers. It was found that laminar composites could be fabricated using either pristine or intercalated graphite fibers using standard fabrication techniques. The intercalated graphite fiber composites had electrical properties which were markedly improved over both the corresponding pitch based and polyacrylonitrile (PAN) based composites. Despite composites resistivities more than an order of magnitude lower for pitch based fiber composites, the lightning strike resistance was poorer than that of the Pan based fiber composites. This leads to the conclusion that the mechanical properties of the pitch fibers are more important than electrical or thermal properties in determining the lightning strike resistance. Based on indicated lightning strike tolerance for high elongation to failure materials, the use of vapor grown, rather than pitch based graphite fibers appears promising.
Dynamic Load Measurement of Ballistic Gelatin Impact Using an Instrumented Tube
NASA Technical Reports Server (NTRS)
Seidt, J. D.; Periira, J. M.; Hammer, J. T.; Gilat, A.; Ruggeri, C. R.
2012-01-01
Bird strikes are a common problem for the aerospace industry and can cause serious damage to an aircraft. Ballistic gelatin is frequently used as a surrogate for actual bird carcasses in bird strike tests. Numerical simulations of these tests are used to supplement experimental data, therefore it is necessary to use numerical modeling techniques that can accurately capture the dynamic response of ballistic gelatin. An experimental technique is introduced to validate these modeling techniques. A ballistic gelatin projectile is fired into a strike plate attached to a 36 in. long sensor tube. Dynamic load is measured at two locations relative to the strike plate using strain gages configured in a full Wheatstone bridge. Data from these experiments are used to validate a gelatin constitutive model. Simulations of the apparatus are analyzed to investigate its performance.
The NASA F-106B Storm Hazards Program
NASA Technical Reports Server (NTRS)
Neely, W. R., Jr.; Fisher, B. D.
1983-01-01
During the NASA LRC Storm Hazards Program, 698 thunderstorm precipitations were made from 1980 to 1983 with an F-106B aircraft in order to record direct lightning strike data and the associated flight conditions. It was found that each of the three composite fin caps tested experienced multiple lightning attachments with only minor cosmetic damage. The maximum current level was only 20 ka, which is well below the design standard of 200 ka; however, indications are that the current rate of rise standard has been approached and may be exceeded in a major strike. The peak lightning strike rate occurred at ambient temperatures between -40 and -45 C, while most previously reported strikes have occurred at or near the freezing level. No significant operational difficulties or major aircraft damage resulting from the thunderstorm penetrations have been found.
Lighnting detection and tracking with consumer electronics
NASA Astrophysics Data System (ADS)
Kamau, Gilbert; van de Giesen, Nick
2015-04-01
Lightning data is not only important for environment and weather monitoring but also for safety purposes. The AS3935 Franklin Lightning Sensor (AMS, Unterpremstaetten, Austria) is a lightning sensor developed for inclusion in consumer electronics such as watches and mobile phones. The AS3935 is small (4mmx4mm) and relatively cost effective (Eu 5). The downside is that only rough distance estimates are provided, as average power is assumed for every lightning strike. To be able to track lightning, a network of devices that monitor and keep track of occurrences of lightning strikes was developed. A communication interface was established between the sensors, a data logging circuit and a microcontroller. The digital outputs of the lightning sensor and data from a GPS are processed by the microcontroller and logged onto an SD card. The interface program enables sampling parameters such as distance from the lightning strike, time of strike occurrence and geographical location of the device. For archiving and analysis purposes, the data can be transferred from the SD card to a PC and results displayed using a graphical user interface program. Data gathered shows that the device can track the frequency and movement of lightning strikes in an area. The device has many advantages as compared to other lightning sensor stations in terms of huge memory, lower power consumption, small size, greater portability and lower cost. The devices were used in a network around Nairobi, Kenya. Through multi-lateration, lightning strikes could be located with a RMSE of 2 km or better.
NASA Astrophysics Data System (ADS)
Li, Haotian; Wei, Meng; Li, Duo; Liu, Yajing; Kim, YoungHee; Zhou, Shiyong
2018-01-01
Recent GPS observations show that slow slip events in south central Alaska are segmented along strike. Here we review several mechanisms that might contribute to this segmentation and focus on two: along-strike variation of slab geometry and effective normal stress. We then test them by running numerical simulations in the framework of rate-and-state friction with a nonplanar fault geometry. Results show that the segmentation is most likely related to the along-strike variation of the effective normal stress on the fault plane caused by the Yakutat Plateau. The Yakutat Plateau could affect the effective normal stress by either lowering the pore pressure in Upper Cook Inlet due to less fluids release or increasing the normal stress due to the extra buoyancy caused by the subducted Yakutat Plateau. We prefer the latter explanation because it is consistent with the relative amplitudes of the effective normal stress in Upper and Lower Cook Inlet and there is very little along-strike variation in Vp/Vs ratio in the fault zone from receiver function analysis. However, we cannot exclude the possibility that the difference in effective normal stress results from along-strike variation of pore pressure due to the uncertainties in the Vp/Vs estimates. Our work implies that a structural anomaly can have a long-lived effect on the subduction zone slip behavior and might be a driving factor on along-strike segmentation of slow slip events.
The verification of lightning location accuracy in Finland deduced from lightning strikes to trees
NASA Astrophysics Data System (ADS)
Mäkelä, Antti; Mäkelä, Jakke; Haapalainen, Jussi; Porjo, Niko
2016-05-01
We present a new method to determine the ground truth and accuracy of lightning location systems (LLS), using natural lightning strikes to trees. Observations of strikes to trees are being collected with a Web-based survey tool at the Finnish Meteorological Institute. Since the Finnish thunderstorms tend to have on average a low flash rate, it is often possible to identify from the LLS data unambiguously the stroke that caused damage to a given tree. The coordinates of the tree are then the ground truth for that stroke. The technique has clear advantages over other methods used to determine the ground truth. Instrumented towers and rocket launches measure upward-propagating lightning. Video and audio records, even with triangulation, are rarely capable of high accuracy. We present data for 36 quality-controlled tree strikes in the years 2007-2008. We show that the average inaccuracy of the lightning location network for that period was 600 m. In addition, we show that the 50% confidence ellipse calculated by the lightning location network and used operationally for describing the location accuracy is physically meaningful: half of all the strikes were located within the uncertainty ellipse of the nearest recorded stroke. Using tree strike data thus allows not only the accuracy of the LLS to be estimated but also the reliability of the uncertainty ellipse. To our knowledge, this method has not been attempted before for natural lightning.
Interaction effects of stride angle and strike pattern on running economy.
Santos-Concejero, J; Tam, N; Granados, C; Irazusta, J; Bidaurrazaga-Letona, I; Zabala-Lili, J; Gil, S M
2014-12-01
This study aimed to investigate the relationship between stride angle and running economy (RE) in athletes with different foot strike patterns. 30 male runners completed 4 min running stages on a treadmill at different velocities. During the test, biomechanical variables such as stride angle, swing time, contact time, stride length and frequency were recorded using an optical measurement system. Their foot strike pattern was determined, and VO2 at velocities below the lactate threshold were measured to calculate RE. Midfoot/forefoot strikers had better RE than rearfoot strikers (201.5±5.6 ml · kg(-1) · km(-1) vs. 213.5±4.2 ml · kg(-1) · km(-1)respectively; p=0.019). Additionally, midfoot/fore-foot strikers presented higher stride angles than rearfoot strikers (p=0.043). Linear modelling analysis showed that stride angle is closely related to RE (r=0.62, p<0.001) and that the effect of stride angle on RE was different in the 2 groups. From an arbitrary value of 4°, a rearfoot strike pattern is likely to be more economical, whereas at any lower degree, the midfoot/forefoot strike pattern appears to be more desirable. A biomechanical running technique characterised by high stride angles and a midfoot/forefoot strike pattern is advantageous for a better RE. Athletes may find stride angle useful for improving RE. © Georg Thieme Verlag KG Stuttgart · New York.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schweizer, Peter E; Cada, Glenn F; Bevelhimer, Mark S
Hydrokinetic energy technologies have been proposed as renewable, environmentally preferable alternatives to fossil fuels for generation of electricity. Hydrokinetic technologies harness the energy of water in motion, either from waves, tides or from river currents. For energy capture from free-flowing rivers, arrays of rotating devices are most commonly proposed. The placement of hydrokinetic devices in large rivers is expected to increase the underwater structural complexity of river landscapes. Moore and Gregory (1988) found that structural complexity increased local fish populations because fish and other aquatic biota are attracted to structural complexity that provides microhabitats with steep flow velocity gradients (Liaomore » 2007). However, hydrokinetic devices have mechanical parts, blades, wings or bars that move through the water column, posing a potential strike or collision risk to fish and other aquatic biota. Furthermore, in a setting with arrays of hydrokinetic turbines the cumulative effects of multiple encounters may increase the risk of strike. Submerged structures associated with a hydrokinetic (HK) project present a collision risk to aquatic organisms and diving birds (Cada et al. 2007). Collision is physical contact between a device or its pressure field and an organism that may result in an injury to that organism (Wilson et al. 2007). Collisions can occur between animals and fixed submerged structures, mooring equipment, horizontal or vertical axis turbine rotors, and structures that, by their individual design or in combination, may form traps. This report defines strike as a special case of collision where a moving part, such as a rotor blade of a HK turbine intercepts the path of an organism of interest, resulting in physical contact with the organism. The severity of a strike incidence may range from minor physical contact with no adverse effects to the organism to severe strike resulting in injury or death of the organism. Harmful effects to animal populations could occur directly (e.g., from strike mortality of individuals) or indirectly (e.g., if the loss of prey species to strike reduces food for predators). Although actively swimming or passively drifting animals may collide with any of the physical structures associated with hydrokinetic devices, turbine rotors are the most likely sources for risk of strike or significant collision (DOE 2009). It is also possible that during a close encounter with a HK device no physical contact will be made between the device and the organism, either because the animal avoids the device by successfully changing its direction of movement, or by successfully evading any moving parts of the device. Oak Ridge National Laboratory (ORNL) has been funded by the US Department of Energy (DOE) Waterpower Program to evaluate strike potential and consequences for Marine and Hydrokinetic (MHK) technologies in rivers and estuaries of the United States. We will use both predictive models and laboratory/field experiments to evaluate the likelihood and consequences of strike at HK projects in rivers. Efforts undertaken at ORNL address three objectives: (1) Assess strike risk for marine and freshwater organisms; (2) Develop experimental procedures to assess the risk and consequences of strike; and (3) Conduct strike studies in experimental flumes and field installations of hydrokinetic devices. During the first year of the study ORNL collected information from the Federal Energy Regulatory Commission (FERC) MHK database about geographical distribution of proposed hydrokinetic projects (what rivers or other types of systems), HK turbine design (horizontal axis, vertical axis, other), description of proposed axial turbine (number of blades, size of blades, rotation rate, mitigation measures), and number of units per project. Where site specific information was available, we compared the location of proposed projects rotors within the channel (e.g., along cutting edge bank, middle of thalweg, near bottom or in midwater) to the general locations of fish in the river (shoreline, bottom/midwater/surface of channel) to ascertain potential interactions. In addition, we are collaborating and communicating with scientists at other national laboratories and industry who are also developing information useful to this task. For example, other studies being funded by DOE include evaluations of different in-current (hydrokinetic) turbine designs for their effects on rates and severity of blade strike and likelihood of cavitation. This report summarizes activities completed during the first year of a three-year study.« less
Brown, K.M.; Erwin, R.M.; Richmond, M.E.; Buckley, P.A.; Tanacredi, J.T.; Avrin, D.
2001-01-01
During the 1980s, the exponential growth of laughing gull (Larus atrfcilla) colonies, from 15 to about 7600 nests in 1990, in the Jamaica Bay Wildlife Refuge and a correlated increase in the bird-strike rate at nearby John F. Kennedy International Airport (New York City) led to a controversy between wildlife and airport managers over the elimination of the colonies. In this paper, we review data to evaluate if: (1) the colonies have increased the level of risk to the flying public; (2) on-colony population control would reduce the presence of gulls, and subsequently bird strikes, at the airport; and (3) all on-airport management alternatives have been adequately implemented. Since 1979, most (2987, 87%) of the 3444 bird strikes (number of aircraft struck) were actually bird carcasses found near runways (cause of death unknown but assumed to be bird strikes by definition). Of the 457 pilot-reported strikes (mean = 23 + 6 aircraft/yr, N = 20 years), 78 (17%) involved laughing gulls. Since a gull-shooting program was initiated on airport property in 1991, over 50,000 adult laughing gulls have been killed and the number of reported bird strikes involving laughing gulls has declined from 6.9 + 2.9 (1983-1990) to 2.8 + 1.3 (1991-1998) aircraft/yr; nongull reported bird strikes, however, have more than doubled (6.4 + 2.6, 1983-1990; 14.9 + 5.1, 1991-1998). We found no evidence to indicate that on-colony management would yield a reduction of bird strikes at Kennedy Airport. Dietary and mark-recapture studies suggest that 60%-90% of the laughing gulls collected on-airport were either failed breeders and/or nonbreeding birds. We argue that the Jamaica Bay laughing gull colonies, the only ones in New York State, should not be managed at least until all on-airport management alternatives have been properly implemented and demonstrated to be ineffective at reducing bird strikes, including habitat alterations and increasing the capability of the bird control unit to eliminate bird flocks on-airport using nonlethal bird dispersal techniques. Because the gull-shooting program may be resulting in a nonsustainable regional population of laughing gulls (>30% decline), we also recommend that attempts be made to initiate an experimental colony elsewhere on Long Island to determine if colony relocation is a feasible management option.
Impact of lightning strikes on hospital functions.
Mortelmans, Luc J M; Van Springel, Gert L J; Van Boxstael, Sam; Herrijgers, Jan; Hoflacks, Stefaan
2009-01-01
Two regional hospitals were struck by lightning during a one-month period. The first hospital, which had 236 beds, suffered a direct strike to the building. This resulted in a direct spread of the power peak and temporary failure of the standard power supply. The principle problems, after restoring standard power supply, were with the fire alarm system and peripheral network connections in the digital radiology systems. No direct impact on the hardware could be found. Restarting the servers resolved all problems. The second hospital, which had 436 beds, had a lightning strike on the premises and mainly experienced problems due to induction. All affected installations had a cable connection from outside in one way or another. The power supplies never were endangered. The main problem was the failure of different communication systems (telephone, radio, intercom, fire alarm system). Also, the electronic entrance control went out. During the days after the lightening strike, multiple software problems became apparent, as well as failures of the network connections controlling the technical support systems. There are very few ways to prepare for induction problems. The use of fiber-optic networks can limit damage. To the knowledge of the authors, these are the first cases of lightning striking hospitals in medical literature.
NASA Astrophysics Data System (ADS)
Laó-Dávila, Daniel A.; Anderson, Thomas H.
2009-12-01
Faults and shear zones recorded in the Monte del Estado and Río Guanajibo serpentinite masses in southwestern Puerto Rico show previously unrecognized southwestward tectonic transport. The orientations of planar and linear structures and the sense of slip along faults and shear zones determined by offset rock layers, drag folds in foliations, and steps in slickensided surfaces and/or S-C fabrics from 1846 shear planes studied at more than 300 stations reveal two predominant groups of faults: 1) northwesterly-striking thrust faults and easterly-striking left-lateral faults and, 2) northwesterly-striking right-lateral faults and easterly-striking thrust faults. Shortening and extension (P and T) axes calculated for geographic domains within the serpentinite reveal early north-trending shortening followed by southwestward-directed movement during which older structures were re-activated. The SW-directed shortening is attributed to transpression that accompanied Late Eocene left-lateral shearing of the serpentinite. A third, younger, group comprising fewer faults consists of northwesterly-striking left-lateral faults and north-directed thrusts that also may be related to the latest transpressional deformation within Puerto Rico. Deformational events in Puerto Rico correlate to tectonic events along the Caribbean-North American plate boundary.
Relationship between Achilles tendon properties and foot strike patterns in long-distance runners.
Kubo, Keitaro; Miyazaki, Daisuke; Tanaka, Shigeharu; Shimoju, Shozo; Tsunoda, Naoya
2015-01-01
The purpose of this study was to investigate the relationship between Achilles tendon properties and foot strike patterns in long-distance runners. Forty-one highly trained male long-distance runners participated in this study. Elongation of the Achilles tendon and aponeurosis of the medial gastrocnemius muscle were measured using ultrasonography, while the participants performed ramp isometric plantar flexion up to the voluntary maximum. The relationship between the estimated muscle force and tendon elongation during the ascending phase was fit to a linear regression, the slope of which was defined as stiffness. In addition, the cross-sectional area of the Achilles tendon was measured using ultrasonography. Foot strike patterns (forefoot, midfoot and rearfoot) during running were determined at submaximal velocity (18 km · h(-1)) on a treadmill. The number of each foot strike runner was 12 for the forefoot (29.3%), 12 for the midfoot (29.3%) and 17 for the rearfoot (41.5%). No significant differences were observed in the variables measured for the Achilles tendon among the three groups. These results suggested that the foot strike pattern during running did not affect the morphological or mechanical properties of the Achilles tendon in long-distance runners.
NASA Astrophysics Data System (ADS)
Koketsu, Kazuki; Miyake, Hiroe; Guo, Yujia; Kobayashi, Hiroaki; Masuda, Tetsu; Davuluri, Srinagesh; Bhattarai, Mukunda; Adhikari, Lok Bijaya; Sapkota, Soma Nath
2016-06-01
The ground motion and damage caused by the 2015 Gorkha, Nepal earthquake can be characterized by their widespread distributions to the east. Evidence from strong ground motions, regional acceleration duration, and teleseismic waveforms indicate that rupture directivity contributed significantly to these distributions. This phenomenon has been thought to occur only if a strike-slip or dip-slip rupture propagates to a site in the along-strike or updip direction, respectively. However, even though the earthquake was a dip-slip faulting event and its source fault strike was nearly eastward, evidence for rupture directivity is found in the eastward direction. Here, we explore the reasons for this apparent inconsistency by performing a joint source inversion of seismic and geodetic datasets, and conducting ground motion simulations. The results indicate that the earthquake occurred on the underthrusting Indian lithosphere, with a low dip angle, and that the fault rupture propagated in the along-strike direction at a velocity just slightly below the S-wave velocity. This low dip angle and fast rupture velocity produced rupture directivity in the along-strike direction, which caused widespread ground motion distribution and significant damage extending far eastwards, from central Nepal to Mount Everest.
Shell Tectonics: A Mechanical Model for Strike-slip Displacement on Europa
NASA Technical Reports Server (NTRS)
Rhoden, Alyssa Rose; Wurman, Gilead; Huff, Eric M.; Manga, Michael; Hurford, Terry A.
2012-01-01
We introduce a new mechanical model for producing tidally-driven strike-slip displacement along preexisting faults on Europa, which we call shell tectonics. This model differs from previous models of strike-slip on icy satellites by incorporating a Coulomb failure criterion, approximating a viscoelastic rheology, determining the slip direction based on the gradient of the tidal shear stress rather than its sign, and quantitatively determining the net offset over many orbits. This model allows us to predict the direction of net displacement along faults and determine relative accumulation rate of displacement. To test the shell tectonics model, we generate global predictions of slip direction and compare them with the observed global pattern of strike-slip displacement on Europa in which left-lateral faults dominate far north of the equator, right-lateral faults dominate in the far south, and near-equatorial regions display a mixture of both types of faults. The shell tectonics model reproduces this global pattern. Incorporating a small obliquity into calculations of tidal stresses, which are used as inputs to the shell tectonics model, can also explain regional differences in strike-slip fault populations. We also discuss implications for fault azimuths, fault depth, and Europa's tectonic history.
Measurements of tungsten migration in the DIII-D divertor
NASA Astrophysics Data System (ADS)
Wampler, W. R.; Rudakov, D. L.; Watkins, J. G.; McLean, A. G.; Unterberg, E. A.; Stangeby, P. C.
2017-12-01
An experimental study of migration of tungsten in the DIII-D divertor is described, in which the outer strike point of L-mode plasmas was positioned on a toroidal ring of tungsten-coated metal inserts. Net deposition of tungsten on the divertor just outside the strike point was measured on graphite samples exposed to various plasma durations using the divertor materials evaluation system. Tungsten coverage, measured by Rutherford backscattering spectroscopy (RBS), was found to be low and nearly independent of both radius and exposure time closer to the strike point, whereas farther from the strike point the W coverage was much larger and increased with exposure time. Depth profiles from RBS show this was due to accumulation of thicker mixed-material deposits farther from the strike point where the plasma temperature is lower. These results are consistent with a low near-surface steady-state coverage on graphite undergoing net erosion, and continuing accumulation in regions of net deposition. This experiment provides data needed to validate, and further improve computational simulations of erosion and deposition of material on plasma-facing components and transport of impurities in magnetic fusion devices. Such simulations are underway and will be reported later.
Federal Aviation Administration Memorandum of Agreement to Address Aircraft-Wildlife Strikes
This Memorandum of Agreement (MOA) establish procedures necessary to coordinate the signatory agencies missions to more effectively address existing and future environmental conditions contributing to aircraft-wildlife strikes throughout the United States.
The Chicago Teachers Strike and Its Public
ERIC Educational Resources Information Center
Shuffelton, Amy B.
2014-01-01
This article considers the 2012 Chicago Teachers Strike in light of John Dewey's "The Public and Its Problems." It engages Dewey's conceptualization of practical reason to challenge the educational reform movement's commitment to technocratic decision-making.
Cardiac Effects of Lightning Strikes
Khan, Sarosh; Ahmad, Mahmood; Fayed, Hossam; Bogle, Richard
2017-01-01
Lightning strikes are a common and leading cause of morbidity and mortality. Multiple organ systems can be involved, though the effects of the electrical current on the cardiovascular system are one of the main modes leading to cardiorespiratory arrest in these patients. Cardiac effects of lightning strikes can be transient or persistent, and include benign or life-threatening arrhythmias, inappropriate therapies from cardiac implantable electronic devices, cardiac ischaemia, myocardial contusion, pericardial disease, aortic injury, as well as cardiomyopathy with associated ventricular failure. Prolonged resuscitation can lead to favourable outcomes especially in young and previously healthy victims. PMID:29018518
2014-02-01
a 0.18 in thick polymer interlayer between two layers of 0.5 in tempered silica based “ soda lime ” glass . A 0.08 in shatter resistant film was...AFCEC-CX-TY-TR-2014-0005 ANALYSIS OF MULTIPLE-IMPACT BALLISTIC PERFORMANCE OF A TEMPERED GLASS LAMINATE WITH A STRIKE FACE FILM Michael A. Magrini...Interim Technical Report 3 JAN 2012 to 2 JAN 2013 Analysis of Multiple-Impact Ballistic Performance of A Tempered Glass Laminate with a Strike Face Film
2004-03-01
probabilistic by design. Finally, as the fragments disperse, fragment density decreases, and the probability of a fragment strike drops rapidly. Given the...Any PPE subjected to such testing needs to be exposed repeatedly to several mines in order to obtain a sufficient number of strikes . This will allow...velocity of each fragment, and the location of fragment strikes cannot be controlled precisely. This means that the same test must be repeated a
NASA Astrophysics Data System (ADS)
Bergh, Steffen; Sylvester, Arthur; Damte, Alula; Indrevær, Kjetil
2014-05-01
The San Andreas fault in southern California records only few large-magnitude earthquakes in historic time, and the recent activity is confined primarily on irregular and discontinuous strike-slip and thrust fault strands at shallow depths of ~5-20 km. Despite this fact, slip along the San Andreas fault is calculated to c. 35 mm/yr based on c.160 km total right lateral displacement for the southern segment of the fault in the last c. 8 Ma. Field observations also reveal complex fault strands and multiple events of deformation. The presently diffuse high-magnitude crustal movements may be explained by the deformation being largely distributed along more gently dipping reverse faults in fold-thrust belts, in contrast to regions to the north where deformation is less partitioned and localized to narrow strike-slip fault zones. In the Mecca Hills of the Salton trough transpressional deformation of an uplifted segment of the San Andreas fault in the last ca. 4.0 My is expressed by very complex fault-oblique and fault-parallel (en echelon) folding, and zones of uplift (fold-thrust belts), basement-involved reverse and strike-slip faults and accompanying multiple and pervasive cataclasis and conjugate fracturing of Miocene to Pleistocene sedimentary strata. Our structural analysis of the Mecca Hills addresses the kinematic nature of the San Andreas fault and mechanisms of uplift and strain-stress distribution along bent fault strands. The San Andreas fault and subsidiary faults define a wide spectrum of kinematic styles, from steep localized strike-slip faults, to moderate dipping faults related to oblique en echelon folds, and gently dipping faults distributed in fold-thrust belt domains. Therefore, the San Andreas fault is not a through-going, steep strike-slip crustal structure, which is commonly the basis for crustal modeling and earthquake rupture models. The fault trace was steep initially, but was later multiphase deformed/modified by oblique en echelon folding, renewed strike-slip movements and contractile fold-thrust belt structures. Notably, the strike-slip movements on the San Andreas fault were transformed outward into the surrounding rocks as oblique-reverse faults to link up with the subsidiary Skeleton Canyon fault in the Mecca Hills. Instead of a classic flower structure model for this transpressional uplift, the San Andreas fault strands were segmented into domains that record; (i) early strike-slip motion, (ii) later oblique shortening with distributed deformation (en echelon fold domains), followed by (iii) localized fault-parallel deformation (strike-slip) and (iv) superposed out-of-sequence faulting and fault-normal, partitioned deformation (fold-thrust belt domains). These results contribute well to the question if spatial and temporal fold-fault branching and migration patterns evolving along non-vertical strike-slip fault segments can play a role in the localization of earthquakes along the San Andreas fault.
Seacrist, Thomas; Belwadi, Aditya; Prabahar, Abhiti; Chamberlain, Samuel; Megariotis, James; Loeb, Helen
2016-09-01
Motor vehicle crashes are the leading cause of death for teens. Previous teen and adult crash rates have been based upon fatal crashes, police-reported crashes, and estimated miles driven. Large-scale naturalistic driving studies offer the opportunity to compute crash rates using a reliable methodology to capture crashes and driving exposure. The Strategic Highway Research Program 2 (SHRP2) Naturalistic Driving Study contains extensive real-world data on teen and adult driving. This article presents findings on the crash rates of novice teen and experienced adult drivers in naturalistic crashes. A subset from the SHRP2 database consisting of 539 crash events for novice teens (16-19 years, n = 549) and experienced adults (35-54 years, n = 591) was used. Onboard instrumentation such as scene cameras, accelerometers, and Global Positioning System logged time series data at 10 Hz. Scene videos were reviewed for all events to identify rear-end striking crashes. Dynamic variables such as acceleration and velocity were analyzed for rear-end striking events. Number of crashes, crash rates, rear-end striking crash severity, and rear-end striking impact velocity were compared between novice teens and experienced adults. Video review of the SHRP2 crashes identified significantly more crashes (P < 0.01) and rear-end striking crashes (P < 0.01) among the teen group than among the adult group. This yielded crash rates of 30.0 crashes per million miles driven for novice teens compared to 5.3 crashes per million miles driven for experienced adults. The crash rate ratio for teens vs. adults was 5.7. The rear-end striking crash rate was 13.5 and 1.8 per million miles driven for novice teens and experienced adults, respectively. The rear-end striking crash rate ratio for teens vs. adults was 7.5. The rear-end striking crash severity measured by the accelerometers was greater (P < 0.05) for the teen group (1.8 ± 0.9 g; median = 1.6 g) than for the adult group (1.1 ± 0.4 g; median = 1.0 g), suggesting that teen crashes tend to be more serious than adult crashes. Increased rear-end striking impact velocity (P < 0.01) was also observed for novice teens (18.8 ± 13.2 mph; median = 18.9 mph) compared to experienced adults (3.3 ± 1.2 mph; median = 2.8 mph). To our knowledge, this is the first study to compare crash rates between teens and adults using a large-scale naturalistic driving database. Unlike previous crash rates, the reported rates reliably control for crash type and driving exposure. These results conform to previous findings that novice teens exhibit increased crash rates compared to experienced adults.
NASA Astrophysics Data System (ADS)
Vannoli, Paola; Bernardi, Fabrizio; Palombo, Barbara; Vannucci, Gianfranco; Console, Rodolfo; Ferrari, Graziano
2016-11-01
On 21 August 1962 an earthquake sequence set off near the city of Benevento, in Italy's southern Apennines. Three earthquakes, the largest having Mw 6.1, struck virtually the same area in less than 40 min (at 18:09, 18:19 and 18:44 UTC, respectively). Several historical earthquakes hit this region, and its seismic hazard is accordingly among the highest countrywide. Although poorly understood in the past, the seismotectonics of this region can be revealed by the 1962 sequence, being the only significant earthquake in the area for which modern seismograms are available. We determine location, magnitude, and nodal planes of the first event (18:09 UTC) of the sequence. The focal mechanism exhibits dominant strike-slip rupture along a north-dipping, E-W striking plane or along a west-dipping, N-S striking plane. Either of these solutions is significantly different from the kinematics of the typical large earthquakes occurring along the crest of the Southern Apennines, such as the 23 November 1980 Irpinia earthquake (Mw 6.9), caused by predominant normal faulting along NW-SE-striking planes. The epicentre of the 21 August 1962, 18:09 event is located immediately east of the chain axis, near one of the three north-dipping, E-W striking oblique-slip sources thought to have caused one of the three main events of the December 1456 sequence (Io XI MCS), the most destructive events in the southern Apennines known to date. We maintain that the 21 August 1962, 18:09 earthquake occurred along the E-W striking fault system responsible for the southernmost event of the 1456 sequence and for two smaller but instrumentally documented events that occurred on 6 May 1971 (Mw 5.0) and 27 September 2012 (Mw 4.6), further suggesting that normal faulting is not the dominant tectonic style in this portion of the Italian peninsula.
Fais, Andrea; Lewis, Tim P; Zitterbart, Daniel P; Álvarez, Omar; Tejedor, Ana; Aguilar Soto, Natacha
2016-01-01
Sperm whales are present in the Canary Islands year-round, suggesting that the archipelago is an important area for this species in the North Atlantic. However, the area experiences one of the highest reported rates of sperm whale ship-strike in the world. Here we investigate if the number of sperm whales found in the archipelago can sustain the current rate of ship-strike mortality. The results of this study may also have implications for offshore areas where concentrations of sperm whales may coincide with high densities of ship traffic, but where ship-strikes may be undocumented. The absolute abundance of sperm whales in an area of 52933 km2, covering the territorial waters of the Canary Islands, was estimated from 2668 km of acoustic line-transect survey using Distance sampling analysis. Data on sperm whale diving and acoustic behaviour, obtained from bio-logging, were used to calculate g(0) = 0.92, this is less than one because of occasional extended periods when whales do not echolocate. This resulted in an absolute abundance estimate of 224 sperm whales (95% log-normal CI 120-418) within the survey area. The recruitment capability of this number of whales, some 2.5 whales per year, is likely to be exceeded by the current ship-strike mortality rate. Furthermore, we found areas of higher whale density within the archipelago, many coincident with those previously described, suggesting that these are important habitats for females and immature animals inhabiting the archipelago. Some of these areas are crossed by active shipping lanes increasing the risk of ship-strikes. Given the philopatry in female sperm whales, replacement of impacted whales might be limited. Therefore, the application of mitigation measures to reduce the ship-strike mortality rate seems essential for the conservation of sperm whales in the Canary Islands.
Fais, Andrea; Lewis, Tim P.; Zitterbart, Daniel P.; Álvarez, Omar; Tejedor, Ana; Aguilar Soto, Natacha
2016-01-01
Sperm whales are present in the Canary Islands year-round, suggesting that the archipelago is an important area for this species in the North Atlantic. However, the area experiences one of the highest reported rates of sperm whale ship-strike in the world. Here we investigate if the number of sperm whales found in the archipelago can sustain the current rate of ship-strike mortality. The results of this study may also have implications for offshore areas where concentrations of sperm whales may coincide with high densities of ship traffic, but where ship-strikes may be undocumented. The absolute abundance of sperm whales in an area of 52933 km2, covering the territorial waters of the Canary Islands, was estimated from 2668 km of acoustic line-transect survey using Distance sampling analysis. Data on sperm whale diving and acoustic behaviour, obtained from bio-logging, were used to calculate g(0) = 0.92, this is less than one because of occasional extended periods when whales do not echolocate. This resulted in an absolute abundance estimate of 224 sperm whales (95% log-normal CI 120–418) within the survey area. The recruitment capability of this number of whales, some 2.5 whales per year, is likely to be exceeded by the current ship-strike mortality rate. Furthermore, we found areas of higher whale density within the archipelago, many coincident with those previously described, suggesting that these are important habitats for females and immature animals inhabiting the archipelago. Some of these areas are crossed by active shipping lanes increasing the risk of ship-strikes. Given the philopatry in female sperm whales, replacement of impacted whales might be limited. Therefore, the application of mitigation measures to reduce the ship-strike mortality rate seems essential for the conservation of sperm whales in the Canary Islands. PMID:26999791
Influence of manatees' diving on their risk of collision with watercraft
Edwards, Holly H.; Martin, Julien; Deutsch, Charles J.; Muller, Robert G; Koslovsky, Stacie M.; Smith, Alexander J.; Barlas, Margie E.
2016-01-01
Watercraft pose a threat to endangered Florida manatees (Trichechus manatus latirostris). Mortality from watercraft collisions has adversely impacted the manatee population’s growth rate, therefore reducing this threat is an important management goal. To assess factors that contribute to the risk of watercraft strikes to manatees, we studied the diving behavior of nine manatees carrying GPS tags and time–depth recorders in Tampa Bay, Florida, during winters 2002–2006. We applied a Bayesian formulation of generalized linear mixed models to depth data to model the probability (Pt) that manatees would be no deeper than 1.25 m from the water’s surface as a function of behavioral and habitat covariates. Manatees above this threshold were considered to be within striking depth of a watercraft. Seventy-eight percent of depth records (individual range 62–86%) were within striking depth (mean = 1.09 m, max = 16.20 m), illustrating how vulnerable manatees are to strikes. In some circumstances manatees made consecutive dives to the bottom while traveling, even in areas >14 m, possibly to conserve energy. This is the first documentation of potential cost-efficient diving behavior in manatees. Manatees were at higher risk of being within striking depth in shallow water (<0.91 m), over seagrass, at night, and while stationary or moving slowly; they were less likely to be within striking depth when ≤50 m from a charted waterway. In shallow water the probability of a manatee being within striking depth was 0.96 (CI = 0.93–0.98) and decreased as water depth increased. The probability was greater over seagrass (Pt = 0.96, CI = 0.93–0.98) than over other substrates (Pt = 0.73, CI = 0.58–0.84). Quantitative approaches to assessing risk can improve the effectiveness of manatee conservation measures by helping identify areas for protection.
The 1999 Hector Mine Earthquake, Southern California: Vector Near-Field Displacements from ERS InSAR
NASA Technical Reports Server (NTRS)
Sandwell, David T.; Sichoix, Lydie; Smith, Bridget
2002-01-01
Two components of fault slip are uniquely determined from two line-of-sight (LOS) radar interferograms by assuming that the fault-normal component of displacement is zero. We use this approach with ascending and descending interferograms from the ERS satellites to estimate surface slip along the Hector Mine earthquake rupture. The LOS displacement is determined by visually counting fringes to within 1 km of the outboard ruptures. These LOS estimates and uncertainties are then transformed into strike- and dip-slip estimates and uncertainties; the transformation is singular for a N-S oriented fault and optimal for an E-W oriented fault. In contrast to our previous strike-slip estimates, which were based only on a descending interferogram, we now find good agreement with the geological measurements, except at the ends of the rupture. The ascending interferogram reveals significant west-sidedown dip-slip (approximately 1.0 m) which reduces the strike-slip estimates by 1 to 2 m, especially along the northern half of the rupture. A spike in the strike-slip displacement of 6 m is observed in central part of the rupture. This large offset is confirmed by subpixel cross correlation of features in the before and after amplitude images. In addition to strike slip and dip slip, we identify uplift and subsidence along the fault, related to the restraining and releasing bends in the fault trace, respectively. Our main conclusion is that at least two look directions are required for accurate estimates of surface slip even along a pure strike-slip fault. Models and results based only on a single look direction could have major errors. Our new estimates of strike slip and dip slip along the rupture provide a boundary condition for dislocation modeling. A simple model, which has uniform slip to a depth of 12 km, shows good agreement with the observed ascending and descending interferograms.
Structural control on the CO2 release west of Mt. Epomeo resurgent block (Ischia, Italy)
NASA Astrophysics Data System (ADS)
de Vita, S.; Marotta, E.; Ventura, G.; Chiodini, G.
2003-04-01
Volcanism at Ischia started more than 150 ka B.P. and continued until the last eruption occurred in 1302 A.D. Ischia is dominated by the caldera forming eruption of Mt. Epomeo Green Tuff (55 ka), which was followed by block resurgence inside the caldera from 33 ka B.P. Resurgence influenced the volcanic activity determining the conditions for magma ascent mainly along the eastern edge of the resurgent block. The resurgent area has a poligonal shape resulting from reactivation of regional faults and by activation of faults related to volcanotectonism. The western sector is bordered by inward dipping, high angle strike-slip/reverse faults testifying a compressional stress regime in this area. These features are cut by late outward dipping normal faults due to gravitational stress. The activity of the volcanic system is testified by seismicity and thermal manifestations. Fumarolic activity concentrates along the faults that borders westward the Mt. Epomeo resurgent block, where the Green Tuff overlies fractured lavas. The structural data show that, outside the most active degassing zone, fractures show a NNW-SSE strike and dip toward Mt. Epomeo. These fractures delimit the northern sector of Mt. Epomeo and show strike and dip consistent with the inward dipping reverse faults. Inside the degassing area fractures show a NW-SE strike and dip outward Mt. Epomeo. These gravity-related faults cut the lavas where the hydrothermal circulation is active. The dip direction of the NW-SE striking fractures within the degassing zone is not consistent with that of the strike-slip/reverse faults (i.e. towards NE) but agrees well with that of the gravity-induced faults (dip direction towards SW). Inside the degassing zone, NW-SE striking faults with lengths not exceeding the hydrothermalized extension occur. This arrangement indicate that the syn-resurgence faults act as permeability barriers, whereas the youngest faults act as the main fluid pathway.
Mortera-Gutierrez, C. A.; Scholl, D. W.; Carlson, R.L.
2003-01-01
Normal faults along the seaward trench slope (STS) commonly strike parallel to the trench in response to bending of the oceanic plate into the subduction zone. This is not the circumstance for the Aleutian Trench, where the direction of convergence gradually changes westward, from normal to transform motion. GLORIA side-scan sonar images document that the Aleutian STS is dominated by faults striking oblique to the trench, west of 179??E and east of 172??W. These images also show a pattern of east-west trending seafloor faults that are aligned parallel to the spreading fabric defined by magnetic anomalies. The stress-strain field along the STS is divided into two domains west and east, respectively, of 179??E. Over the western domain, STS faults and nodal planes of earthquakes are oriented oblique (9??-46??) to the trench axis and (69??-90??) to the magnetic fabric. West of 179??E, STS fault strikes change by 36?? from the E-W trend of STS where the trench-parallel slip gets larger than its orthogonal component of convergence. This rotation indicates that horizontal stresses along the western domain of the STS are deflected by the increasing obliquity in convergence. An analytical model supports the idea that strikes of STS faults result from a superposition of stresses associated with the dextral shear couple of the oblique convergence and stresses caused by plate bending. For the eastern domain, most nodal planes of earthquakes strike parallel to the outer rise, indicating bending as the prevailing mechanism causing normal faulting. East of 172??W, STS faults strike parallel to the magnetic fabric but oblique (10??-26??) to the axis of the trench. On the basis of a Coulomb failure criterion the trench-oblique strikes probably result from reactivation of crustal faults generated by spreading. Copyright 2003 by the American Geophysical Union.
Transpressive systems - 4D analogue modelling with X-ray computed tomography
NASA Astrophysics Data System (ADS)
Klinkmueller, M.; Schreurs, G.
2009-04-01
A series of 4D transpressional analogue models was analyzed with X-ray computed tomography (CT). A new modular sandbox with two base-plates was used to simulate strike-slip transpressional deformation and oblique basin inversion. The model itself is constructed on top of an assemblage made up of plexiglas- and foam-bars that enable strain distribution. Models consisted of a basal polydimethylsiloxane (PDMS) layer overlain by a quartz sand pack (Schreurs 1994; Schreurs & Colletta, 1998). The PDMS layer distributes the strike-slip shear component of deformation evenly over the entire model. The initial length of the model was 80 cm. The initial width of the model was 25 cm and was extended to maximal 27 cm to form graben structures. During extension a syn-sedimentary sequence of granular materials was added before transpression was started. Different ratios of shear strain rate and shortening strain rate were applied to investigate the influence on fault generation in both set-ups. To avoid side effects, our fault analysis focused on the central part of the model with a safety distance to the strike-slip orthogonal sidewalls of 20 cm. At low-angle transpression, strike-slip faults form predominantly during initial stages of deformation. They merge in part with pre-existing graben structures and form an anastomosing major fault zone that strikes subparallel to the long dimension of the model. At high-angle transpression, thrusts striking parallel to the long dimension of the model dominate. Thrust localisation is strongly controlled by the position of the pre-existing graben. REFERENCES Schreurs, G. (1994). Experiments on strike-slip faulting and block rotation. Geology, 22, 567-570. Schreurs, G. & Colletta, B. (1998). Analogue modelling of faulting in zones of continental transpression and transtension. In: Holdsworth, R.E., Strachan, R.A. & Dewey, J.F. (eds.). Continental Transpressional and Transtensional Tectonics. Geological Society, London, Special Publications, 135, 59-79.
Influence of Manatees' Diving on Their Risk of Collision with Watercraft
Edwards, Holly H.; Martin, Julien; Deutsch, Charles J.; Muller, Robert G.; Koslovsky, Stacie M.; Smith, Alexander J.; Barlas, Margaret E.
2016-01-01
Watercraft pose a threat to endangered Florida manatees (Trichechus manatus latirostris). Mortality from watercraft collisions has adversely impacted the manatee population’s growth rate, therefore reducing this threat is an important management goal. To assess factors that contribute to the risk of watercraft strikes to manatees, we studied the diving behavior of nine manatees carrying GPS tags and time–depth recorders in Tampa Bay, Florida, during winters 2002–2006. We applied a Bayesian formulation of generalized linear mixed models to depth data to model the probability (Pt) that manatees would be no deeper than 1.25 m from the water’s surface as a function of behavioral and habitat covariates. Manatees above this threshold were considered to be within striking depth of a watercraft. Seventy-eight percent of depth records (individual range 62–86%) were within striking depth (mean = 1.09 m, max = 16.20 m), illustrating how vulnerable manatees are to strikes. In some circumstances manatees made consecutive dives to the bottom while traveling, even in areas >14 m, possibly to conserve energy. This is the first documentation of potential cost-efficient diving behavior in manatees. Manatees were at higher risk of being within striking depth in shallow water (<0.91 m), over seagrass, at night, and while stationary or moving slowly; they were less likely to be within striking depth when ≤50 m from a charted waterway. In shallow water the probability of a manatee being within striking depth was 0.96 (CI = 0.93–0.98) and decreased as water depth increased. The probability was greater over seagrass (Pt = 0.96, CI = 0.93–0.98) than over other substrates (Pt = 0.73, CI = 0.58–0.84). Quantitative approaches to assessing risk can improve the effectiveness of manatee conservation measures by helping identify areas for protection. PMID:27049326
Hinkelbein, J; Spelten, O; Wetsch, W A
2013-01-01
Up to 32.2% of patients in a burn center suffer from electrical injuries. Of these patients, 2-4% present with lightning injuries. In Germany, approximately 50 people per year are injured by a lightning strike and 3-7 fatally. Typically, people involved in outdoor activities are endangered and affected. A lightning strike usually produces significantly higher energy doses as compared to those in common electrical injuries. Therefore, injury patterns vary significantly. Especially in high voltage injuries and lightning injuries, internal injuries are of special importance. Mortality ranges between 10 and 30% after a lightning strike. Emergency medical treatment is similar to common electrical injuries. Patients with lightning injuries should be transported to a regional or supraregional trauma center. In 15% of all cases multiple people may be injured. Therefore, it is of outstanding importance to create emergency plans and evacuation plans in good time for mass gatherings endangered by possible lightning.
NASA Technical Reports Server (NTRS)
Fisher, B. D.; Brown, P. W.; Plumer, J. A.
1985-01-01
Data on 637 direct lightning strikes and 117 close flashes observed by the NASA instrumented F-106B aircraft as part of the Storm Hazards Program at NASA Langley during 1980-1984 are compiled and analyzed, updating the report of Fisher and Plumer (1983). The airborne and ground-based measurement and recording apparatus and the flight and data-reduction procedures are described, and the results are discussed in terms of lightning-strike-conducive flight conditions and lightning attachment patterns. A peak strike rate of 2.1/min is found at altitude 38,000-40,000 ft and temperature below -40 C, with very few strikes below 20,000 ft. Four categories of swept-flash attachment pattern are identified, but it is pointed out that all exterior surfaces of the F-106B are potential attachment sites.
NASA Astrophysics Data System (ADS)
Kaplay, R. D.; Kumar, T. Vijay; Mukherjee, Soumyajit; Wesanekar, P. R.; Babar, Md; Chavan, Sumeet
2017-07-01
We study the margin of South East Deccan Volcanic Province around Kinwat lineament, Maharashtra, India, which is NW extension of the Kaddam Fault. Structural field studies document ˜ E-W strike-slip mostly brittle faults from the basement granite. We designate this as `Western boundary East Dharwar Craton Strike-slip Zone' (WBEDCSZ). At local level, the deformation regime from Kinwat, Kaddam Fault, micro-seismically active Nanded and seismically active Killari corroborate with the nearby lineaments. Morphometric analyses suggest that the region is moderately tectonically active. The region of intense strike-slip deformation lies between seismically active fault along Tapi in NW and Bhadrachalam in the SE part of the Kaddam Fault/lineament. The WBEDCSZ with the surface evidences of faulting, presence of a major lineaments and intersection of faults could be a zone of intraplate earthquake.
NASA Astrophysics Data System (ADS)
Chinnasee, Chamnan; Nadzalan, Ali Md; Ikhwan Mohamad, Nur; Sazili, Abdul Hafiz Ahmad; Hemapandha, Witthaya; Azizuddin Khan, Thariq Khan; Pimjan, Luckhana; Tan, Kevin
2018-05-01
This study was conducted to determine and compare the kinematics of knee strike in MuayThai between dominant and non-dominant lower limb. Ten MuayThai beginners (mean age = 20 ± 1 years old) with less than one week experiences in MuayThai training were recruited and were asked to perform three trials of knee strikes for each leg (dominant and non-dominant). Joint angles and angular velocity of the movement were assessed for each trial. Repeated measure multivariate analyses of variances (MANOVA) were performed to compare the kinematics data between the dominant and non-dominant lower limb. Results showed no significant differences existed in all the joint kinematics examined between dominant and non-dominant lower limb. As the conclusion, MuayThai beginners demonstrated no differences of joint kinematics during knee strike between dominant and non-dominant lower limb.
Electric converters of electromagnetic strike machine with battery power
NASA Astrophysics Data System (ADS)
Usanov, K. M.; Volgin, A. V.; Kargin, V. A.; Moiseev, A. P.; Chetverikov, E. A.
2018-03-01
At present, the application of pulse linear electromagnetic engines to drive strike machines for immersion of rod elements into the soil, strike drilling of shallow wells, dynamic probing of soils is recognized as quite effective. The pulse linear electromagnetic engine performs discrete consumption and conversion of electrical energy into mechanical work. Pulse dosing of a stream transmitted by the battery source to the pulse linear electromagnetic engine of the energy is provided by the electrical converter. The electric converters with the control of an electromagnetic strike machine as functions of time and armature movement, which form the unipolar supply pulses of voltage and current necessary for the normal operation of a pulse linear electromagnetic engine, are proposed. Electric converters are stable in operation, implement the necessary range of output parameters control determined by the technological process conditions, have noise immunity and automatic disconnection of power supply in emergency modes.
Structural evolution of the Ural-Tian Shan junction: A view from Karatau ridge, South Kazakhstan
NASA Astrophysics Data System (ADS)
Alexeiev, Dmitriy V.; Cook, Harry E.; Buvtyshkin, Vasiliy M.; Golub, Lyudmila Y.
2009-02-01
The deformation history of the Late Palaeozoic Ural-Tian Shan junction is discussed for the example of the Karatau ridge in southern Kazakhstan. Three deformation events are recognized. The Late Carboniferous D1 event is characterized by Laramide-style thrust-and-fold structures on the southern margin of Kazakhstan with shortening in a NE-SW direction. The Latest Permian and Triassic D2 event is controlled by compression in an east-west direction, which reflects collisional deformation in the Urals. The main structures are submeridional folds and north-west-striking sinistral strike-slip faults. The Triassic D3 event with shortening in a north-south direction reflects collision of the Turan microcontinent against the southern margin of Kazakhstan. The main structures are north-west-striking dextral strike-slip faults. Our new data provides important clues for the reconstruction of pre-Cretaceous structures between the Urals and the Tian Shan.
NASA Technical Reports Server (NTRS)
Zaepfel, K. P.; Fisher, B. D.; Ott, M. S.
1985-01-01
As part of the NASA Langley Research Center Storm Hazards Program, 241 thunderstorm penetrations were made in 1982 with an F-106B airplane in order to record direct-strike lightning data and the associated flight conditions. During these penetrations, the airplane received 156 direct lightning strikes; in addition, lightning transient data were recorded from 26 nearby lightning flashes. The tests were conducted within 150 nautical miles of Hampton, Virginia, assisted by ground-based weather-radar guidance from the NASA Wallops Flight Facility. The photographs of the lightning attachments taken from two onboard 16-mm color movie cameras and the associated strike attachment patterns are presented. A table of the flight conditions recorded at the time of each lightning event, and a table in which the data are cross-referenced with the previously published lightning electromagnetic waveform data are included.
Tectonic escape in the evolution of the continental crust
NASA Technical Reports Server (NTRS)
Burke, K.; Sengor, C.
1986-01-01
The continental crust originated by processes similar to those operating today and continents consist of material most of which originated long ago in arc-systems that have later been modified, especially at Andean margins and in continental collisions where crustal thickening is common. Collision-related strike-slip motion is a general process in continental evolution. Because buoyant continental (or arc) material generally moves during collision toward a nearby oceanic margin where less buoyant lithosphere crops out, the process of major strike-slip dominated motion toward a 'free-face' is called 'tectonic escape'. Tectonic escape is and has been an element in continental evolution throughout recorded earth-history. It promotes: (1) rifting and the formation of rift-basins with thinning of thickened crust; (2) pervasive strike-slip faulting late in orogenic history which breaks up mountain belts across strike and may juxtapose unrelated sectors in cross-section; (3) localized compressional mountains and related foreland-trough basins.
Management of patients during hunger strike and refeeding phase.
Eichelberger, M; Joray, M L; Perrig, M; Bodmer, M; Stanga, Z
2014-01-01
Hunger strikers resuming nutritional intake may develop a life-threatening refeeding syndrome (RFS). Consequently, hunger strikers represent a core challenge for the medical staff. The objective of the study was to test the effectiveness and safety of evidence-based recommendations for prevention and management of RFS during the refeeding phase. This was a retrospective, observational data analysis of 37 consecutive, unselected cases of prisoners on a hunger strike during a 5-y period. The sample consisted of 37 cases representing 33 individual patients. In seven cases (18.9%), the hunger strike was continued during the hospital stay, in 16 episodes (43.2%) cessation of the hunger strike occurred immediately after admission to the security ward, and in 14 episodes (37.9%) during hospital stay. In the refeed cases (n = 30), nutritional replenishment occurred orally, and in 25 (83.3%) micronutrients substitutions were made based on the recommendations. The gradual refeeding with fluid restriction occurred over 10 d. Uncomplicated dyselectrolytemia was documented in 12 cases (40%) within the refeeding phase. One case (3.3%) presented bilateral ankle edemas as a clinical manifestation of moderate RFS. Intensive medical treatment was not necessary and none of the patients died. Seven episodes of continued hunger strike were observed during the entire hospital stay without medical complications. Our data suggested that seriousness and rate of medical complications during the refeeding phase can be kept at a minimum in a hunger strike population. This study supported use of recommendations to optimize risk management and to improve treatment quality and patient safety in this vulnerable population. Copyright © 2014 Elsevier Inc. All rights reserved.
Strike-slip faulting at Thebes Gap, Missouri and Illinois; implications for New Madrid tectonism
Harrison, Richard W.; Schultz, Art
1994-01-01
Numerous NNE and NE striking strike-slip faults and associated normal faults, folds, and transtensional grabens occur in the Thebes Gap area of Missouri and Illinois. These structures developed along the northwestern margin of the buried Reelfoot rift of Precambrian-Cambrian age at the northern edge of the Mississippi embayment. They have had a long-lived and complex structural history. This is an area of recent moderate seismicity, approximately 45 km north of the New Madrid seismic zone. Stratigraphic evidence suggests that these faults were active during the Middle Ordovician. They were subsequently reactivated between the Early Devonian and Late Cretaceous, probably in response to both the Acadian and Ouachita orogenies. Deformation during this period was characterized by strongly faulted and folded Ordovician through Devonian rocks. In places, these deformed rocks are overlain with angular unconformity by undeformed Cretaceous strata. Fault motion is interpreted as dominantly strike slip. A still younger period of reactivation involved Late Cretaceous and Cenozoic formations as young as the Miocene or Pliocene Mounds Gravel. These formations have experienced both minor high-angle normal faulting and subsequent major, right-lateral strike-slip faulting. En echelon north-south folds, ENE striking normal faults, regional fracture patterns, and drag folds indicate the right-lateral motion for this major episode of faulting which predates deposition of Quaternary loess. Several nondefinitive lines of evidence suggest Quaternary faulting. Similar fault orientations and kinematics, as well as recent seismicity and proximity, clearly suggest a structural relationship between deformation at Thebes Gap and tectonism associated with the New Madrid area.
Feed-forward motor control of ultrafast, ballistic movements.
Kagaya, K; Patek, S N
2016-02-01
To circumvent the limits of muscle, ultrafast movements achieve high power through the use of springs and latches. The time scale of these movements is too short for control through typical neuromuscular mechanisms, thus ultrafast movements are either invariant or controlled prior to movement. We tested whether mantis shrimp (Stomatopoda: Neogonodactylus bredini) vary their ultrafast smashing strikes and, if so, how this control is achieved prior to movement. We collected high-speed images of strike mechanics and electromyograms of the extensor and flexor muscles that control spring compression and latch release. During spring compression, lateral extensor and flexor units were co-activated. The strike initiated several milliseconds after the flexor units ceased, suggesting that flexor activity prevents spring release and determines the timing of strike initiation. We used linear mixed models and Akaike's information criterion to serially evaluate multiple hypotheses for control mechanisms. We found that variation in spring compression and strike angular velocity were statistically explained by spike activity of the extensor muscle. The results show that mantis shrimp can generate kinematically variable strikes and that their kinematics can be changed through adjustments to motor activity prior to the movement, thus supporting an upstream, central-nervous-system-based control of ultrafast movement. Based on these and other findings, we present a shishiodoshi model that illustrates alternative models of control in biological ballistic systems. The discovery of feed-forward control in mantis shrimp sets the stage for the assessment of targets, strategic variation in kinematics and the role of learning in ultrafast animals. © 2016. Published by The Company of Biologists Ltd.
Similarities and differences among half-marathon runners according to their performance level
Morante, Juan Carlos; Gómez-Molina, Josué; García-López, Juan
2018-01-01
This study aimed to identify the similarities and differences among half-marathon runners in relation to their performance level. Forty-eight male runners were classified into 4 groups according to their performance level in a half-marathon (min): Group 1 (n = 11, < 70 min), Group 2 (n = 13, < 80 min), Group 3 (n = 13, < 90 min), Group 4 (n = 11, < 105 min). In two separate sessions, training-related, anthropometric, physiological, foot strike pattern and spatio-temporal variables were recorded. Significant differences (p<0.05) between groups (ES = 0.55–3.16) and correlations with performance were obtained (r = 0.34–0.92) in training-related (experience and running distance per week), anthropometric (mass, body mass index and sum of 6 skinfolds), physiological (VO2max, RCT and running economy), foot strike pattern and spatio-temporal variables (contact time, step rate and length). At standardized submaximal speeds (11, 13 and 15 km·h-1), no significant differences between groups were observed in step rate and length, neither in contact time when foot strike pattern was taken into account. In conclusion, apart from training-related, anthropometric and physiological variables, foot strike pattern and step length were the only biomechanical variables sensitive to half-marathon performance, which are essential to achieve high running speeds. However, when foot strike pattern and running speeds were controlled (submaximal test), the spatio-temporal variables were similar. This indicates that foot strike pattern and running speed are responsible for spatio-temporal differences among runners of different performance level. PMID:29364940
Federal Register 2010, 2011, 2012, 2013, 2014
2013-09-20
... of facilities or network(s); terror threats; strikes and similar labor actions; civil unrest... network(s). (3) Terror threats; strikes and similar labor actions. (4) Civil unrest, uprising or riot. (5...
Wildlife strikes to Canadian aircraft : 2008 summary report
DOT National Transportation Integrated Search
2008-01-01
This report provides a summary of Canadian wildlife strike statistics for 2008. It is : intended for the use of all stakeholders involved with Airport Bird and Mammal Control : Programs. Included in this group are pilots, airfield staff, airline main...
Three-dimensional models of deformation near strike-slip faults
ten Brink, Uri S.; Katzman, Rafael; Lin, J.
1996-01-01
We use three-dimensional elastic models to help guide the kinematic interpretation of crustal deformation associated with strike-slip faults. Deformation of the brittle upper crust in the vicinity of strike-slip fault systems is modeled with the assumption that upper crustal deformation is driven by the relative plate motion in the upper mantle. The driving motion is represented by displacement that is specified on the bottom of a 15-km-thick elastic upper crust everywhere except in a zone of finite width in the vicinity of the faults, which we term the "shear zone." Stress-free basal boundary conditions are specified within the shear zone. The basal driving displacement is either pure strike slip or strike slip with a small oblique component, and the geometry of the fault system includes a single fault, several parallel faults, and overlapping en echelon faults. We examine the variations in deformation due to changes in the width of the shear zone and due to changes in the shear strength of the faults. In models with weak faults the width of the shear zone has a considerable effect on the surficial extent and amplitude of the vertical and horizontal deformation and on the amount of rotation around horizontal and vertical axes. Strong fault models have more localized deformation at the tip of the faults, and the deformation is partly distributed outside the fault zone. The dimensions of large basins along strike-slip faults, such as the Rukwa and Dead Sea basins, and the absence of uplift around pull-apart basins fit models with weak faults better than models with strong faults. Our models also suggest that the length-to-width ratio of pull-apart basins depends on the width of the shear zone and the shear strength of the faults and is not constant as previously suggested. We show that pure strike-slip motion can produce tectonic features, such as elongate half grabens along a single fault, rotated blocks at the ends of parallel faults, or extension perpendicular to overlapping en echelon faults, which can be misinterpreted to indicate a regional component of extension. Zones of subsidence or uplift can become wider than expected for transform plate boundaries when a minor component of oblique motion is added to a system of parallel strike-slip faults.
NASA Astrophysics Data System (ADS)
Little, Timothy A.
1990-08-01
The Border Ranges fault system (BRFS) bounds the inboard edge of the subduction-accretion complex of southern Alaska. In Eocene time a central segment of this fault system was reactivated as a zone of dextral wrench- and oblique-slip faulting having a cumulative strike-slip offset of at least several tens of kilometers, but probably less than 100 km. Early wrench folds are upright, trend at less than 45° to the strike of adjacent faults and developed with fold axes oriented subparallel to the axis of maximum incremental stretch λ1. These en echelon folds rotated and tightened with progressive deformation and then were overprinted by younger wrench folds that trend at about 60° to adjacent throughgoing faults. The latter folds are interpreted as forming during a late increment of distributed wrench deformation within the BRFS that included a component of extension (divergence) orthogonal to the mean strike of the fault system. A sharp releasing bend in exposures of a strike-slip fault originally at >4 km depth today coincides with a narrow pull-apart graben bounded by oblique-normal faults that dip toward the basin. Widening of this pull-apart graben by brittle faulting and dike intrusion accommodated less than 2 km of strike-slip and was a late-stage phenomenon, possibly occurring at supracrustal levels. Prior to formation of this graben during a period of predominantly ductile deformation at deeper structural levels, wrench-folded rocks on one side of the nonplanar fault were translated around the releasing bend without significant faulting or loss of coherence. Kinematically, the earlier deformation was accomplished by fault-bend folding and rotation of a relatively deformable block as it passed through a system of upright megakinks. Such a ductile mechanism of fault block translation around a strike-slip bend may be typical of intermediate levels of the crust beneath pull-apart grabens and may be transitional downward into heterogeneous laminar flow occuring along curved segments of ductile shear zones. Some degree of fault-bend folding of strike-slip fault blocks around releasing bends may be one reason why the amount of extension measured across natural pull-apart basins is commonly observed to be less than the amount of strike-slip along their master faults.
The Role of Near-Fault Relief in Creating and Maintaining Strike-Slip Landscape Features
NASA Astrophysics Data System (ADS)
Harbert, S.; Duvall, A. R.; Tucker, G. E.
2016-12-01
Geomorphic landforms, such as shutter ridges, offset river terraces, and deflected stream channels, are often used to assess the activity and slip rates of strike-slip faults. However, in some systems, such as parts of the Marlborough Fault System (South Island, NZ), an active strike-slip fault does not leave a strong landscape signature. Here we explore the factors that dampen or enhance the landscape signature of strike-slip faulting using the Channel-Hillslope Integrated Landscape Development model (CHILD). We focus on variables affecting the length of channel offsets, which enhance the signature of strike-slip motion, and the frequency of stream captures, which eliminate offsets and reduce this signature. We model a strike-slip fault that passes through a mountain ridge, offsetting streams that drain across this fault. We use this setup to test the response of channel offset length and capture frequency to fault characteristics, such as slip rate and ratio of lateral to vertical motion, and to landscape characteristics, such as relief contrasts controlled by erodibility. Our experiments show that relief downhill of the fault, whether generated by differential uplift across the fault or by an erodibility contrast, has the strongest effect on offset length and capture frequency. This relief creates shutter ridges, which block and divert streams while being advected along a fault. Shutter ridges and the streams they divert have long been recognized as markers of strike-slip motion. Our results show specifically that the height of shutter ridges is most responsible for the degree to which they create long channel offsets by preventing stream captures. We compare these results to landscape metrics in the Marlborough Fault System, where shutter ridges are common and often lithologically controlled. We compare shutter ridge length and height to channel offset length in order to assess the influence of relief on offset channel features in a real landscape. Based on our model and field results, we conclude that vertical relief is important for generating and preserving offset features that are viewed as characteristic of a strike-slip fault. Therefore, the geomorphic expression of a fault may be dependent on characteristics of the surrounding landscape rather than primarily a function of the nature of slip on the fault.
Bade, Michael B.; Aaron, Katie
2016-01-01
ABSTRACT Background Clinicians are interested in the foot strike pattern (FSP) in runners because of the suggested relationship between the strike pattern and lower extremity injury. Purpose The purpose of this study was to assess the ability of collegiate cross-country runners and recreational runners to self-report their foot strike pattern during running. Study Design Cross-sectional Study Methods Twenty-three collegiate cross-country and 23 recreational runners voluntarily consented to participate. Inclusion criteria included running at least 18 miles per week, experience running on a treadmill, no history of lower extremity congenital or traumatic deformity, or acute injury three months prior to the start of the study. All participants completed a pre-test survey to indicate their typical foot strike pattern during a training run (FSPSurvey). Prior to running, reflective markers were placed on the posterior midsole and the vamp of the running shoe. A high-speed camera was used to film each runner in standing and while running at his or her preferred speed on a treadmill. The angle between the vector formed by the two reflective markers and the superior surface of the treadmill was used to calculate the foot strike angle (FSA). To determine the foot strike pattern from the video data (FSPVideo), the static standing angle was subtracted from the FSA at initial contact of the shoe on the treadmill. In addition to descriptive statistics, percent agreement and Chi square analysis was used to determine distribution differences between the video analysis results and the survey. Results The results of the chi-square analysis on the distribution of the FSPSurvey in comparison to the FSPVideo were significantly different for both the XCRunners (p < .01; Chi-square = 8.77) and the REC Runners (p < .0002; Chi-square = 16.70). The cross-country and recreational runners could correctly self-identified their foot strike pattern 56.5% and 43.5% of the time, respectively. Conclusion The findings of this study suggest that the clinician cannot depend on an experienced runner to correctly self-identify their FSP. Clinicians interested in knowing the FSP of a runner should consider performing the two-dimensional video analysis described in this paper. Level of Evidence 3 PMID:27274421
NASA Astrophysics Data System (ADS)
Nukman, M.; Moeck, I.
2012-04-01
The Tarutung Basin is one of several basins along the prominent Sumatra Fault System (SFS) which represents a dextral strike slip fault zone segmented into individual fault strands. The basins are located at right-stepping transfer. The Tarutung Basin hosts geothermal manifestations such as hot springs and travertines indicating a geothermal system with some decent potential in the subsurface. As part of geothermal exploration, field geology is investigated focusing on how the structural setting controls the thermal manifestation distribution. A complex fault pattern is now newly mapped and evidences sinistral faults striking E-W (Silangkitang), normal faults striking SE-NW at the eastern strand of Tarutung Basin (Sitompul) and normal faults striking NW-SE at the western strand of the basin (Sitaka). These structures form an angle greater than 450 with respect to the current maximum principal stress which is oriented in N-S. Secondary sinistral shear fractures identified as antithetic Riedel shears can be correlated with hot spring locations at Silangkitang, forming an angle of 500 with respect to the current maximum stress. A large angle of normal fault and antithetic Riedel shear trend with respect to the current maximum stress direction indicates that the structures have been rotated. Unidentified dextral strike slip faults might exist at the eastern strand of Tarutung Basin to accommodate the clockwise rotation between the eastern boundary of the basin and the NW-SE striking normal fault of Panabungan. Normal faults striking parallel with the SFS East of the basin are interpreted as dilatational jogs caused by the clockwise rotated block movement with respect to the NW-SE fault trend sinistral shear along ENE-WSW faults. Silicified pryroclastics in association with large discharge at hot springs at these NW-SE striking normal faults support this hypothesis. As proposed by Nivinkovich (1976) and Nishimura (1986) Sumatra has rotated 20° clockwise since the last two million years due to the increase in sea-floor spreading rate of the Indian-Australian plate. The combination of regional clockwise rotation of Sumatra with local clockwise rotation caused by simple shear along the dextral SFS might generate the complex fault pattern which controls fluid flow of thermal water and placement of hot springs. Acknowledgements : Deutscher Akademischer Austausch Dienst, DAAD. German Ministry for Education and Research, BMBF. Badan Geologi - KESDM Bandung, Indonesia.
Choy, G.L.; Zednik, J.
1997-01-01
In terms of seismically radiated energy or moment release, the earthquake of 20 January 1990 in the Manjil Basin-Alborz Mountain region of Iran is the second largest strike-slip earthquake to have occurred in an intracontinental setting in the past decade. It caused enormous loss of life and the virtual destruction of several cities. Despite a very large meizoseismal area, the identification of the causative faults has been hampered by the lack of reliable earthquake locations and conflicting field reports of surface displacement. Using broadband data from global networks of digitally recording seismographs, we analyse broadband seismic waveforms to derive characteristics of the rupture process. Complexities in waveforms generated by the earthquake indicate that the main shock consisted of a tiny precursory subevent followed in the next 20 seconds by a series of four major subevents with depths ranging from 10 to 15 km. The focal mechanisms of the major subevents, which are predominantly strike-slip, have a common nodal plane striking about 285??-295??. Based on the coincidence of this strike with the dominant tectonic fabric of the region we presume that the EW striking planes are the fault planes. The first major subevent nucleated slightly south of the initial precursor. The second subevent occurred northwest of the initial precursor. The last two subevents moved progressively southeastward of the first subevent in a direction collinear with the predominant strike of the fault planes. The offsets in the relative locations and the temporal delays of the rupture subevents indicate heterogeneous distribution of fracture strength and the involvement of multiple faults. The spatial distribution of teleseismic aftershocks, which at first appears uncorrelated with meizoseismal contours, can be decomposed into stages. The initial activity, being within and on the periphery of the rupture zone, correlates in shape and length with meizoseismal lines. In the second stage of activity the aftershock zone expands and appears to cluster about the geomorphic and geologic features several tens of kilometres from the rupture zone. The activity is interpreted as a regional response to quasistatic stress migration along zones of tectonic weakness. The radiated energy of the main shock and the estimate of seismic moment yields an apparent stress of 20 bars. High apparent stress may be typical of strike slip earthquakes occurring in intracontinental environments undergoing continental collision.
NASA Astrophysics Data System (ADS)
Blakely, R. J.; Sherrod, B. L.; Glen, J. M. G.; Ritzinger, B. T.; Staisch, L.
2017-12-01
High-resolution aeromagnetic surveys of Washington and Oregon, acquired over the past two decades by the U.S. Geological Survey, serve as proxies for geologic mapping in a terrain modified by glacial and catastrophic flood processes and covered by vegetation and urban development. In concert with geologic mapping and ancillary geophysical measurements, these data show possible kinematic links between forearc and backarc regions and have improved understanding of Cascadia crustal framework. Here we investigate a possible link between the NW-striking Wallula fault zone (WFZ), a segment of the Olympic-Wallowa lineament (OWL), and the N-striking Hite fault in Cascadia's backarc. Strike-slip displacement on the WFZ is indicated by offset of NW-striking Ice Harbor dikes (8.5 Ma), as displayed in magnetic anomalies. An exposed dike immediately south of the Walla Walla River has been used by others to argue against strike-slip displacement; i.e., the exposure lies south of one strand of the WFZ but is not displaced with respect to its linear magnetic anomaly north of the fault. However, high-resolution magnetic anomalies and a recently discovered, 25-km-long LiDAR scarp show that the dike exposure actually lies north of the fault and thus is irrelevant in determining strike-slip displacement on the fault. Our most recent magnetic survey illuminates with unprecedented detail strands of the N-striking Hite fault system and structural links to the WFZ. The survey lies over an area underlain by strongly magnetic Miocene Columbia River flood basalts (CRB) and older intrusive and volcanic rocks. NW-striking magnetic anomalies associated with the WFZ do not extend eastward beyond the Hite fault, suggesting that this is the region at which strain is transferred from the OWL. Magnetic anomalies originating from CRB across the Hite fault serve as piercing points and indicate 1.5 to 2 km of sinistral slip since middle Miocene. Vertical offsets in depth to magnetic basement across the fault suggest that vertical displacement also was important. We conclude that the WFZ and Hite fault are kinematically linked and that both exhibit oblique-slip displacement. Faults north and south of the WFZ are dominantly compressional and extensional, respectively, suggesting that the Hite fault serves as a backstop to dextral slip on the OWL.
NASA Astrophysics Data System (ADS)
Cameron, M. E.; Smith-Konter, B. R.; Burkhard, L. M.; Collins, G. C.; Seifert, F.; Pappalardo, R. T.
2015-12-01
Ganymede exhibits two geologically distinct terrains known as dark and light (grooved) terrain. The mechanism for a transition from dark to light terrain remains unclear; however, inferences of strike-slip faulting and distributed shear zones suggest that strike-slip tectonism may be important to the structural development of Ganymede's surface and in this transition. Here we investigate the role of tidal stresses on Ganymede in the formation and evolution of strike-slip structures in both dark and grooved terrains. Using numerical code SatStress, we calculate both diurnal and non-synchronous rotation (NSR) tidal stresses at Ganymede's surface. Specifically, we investigate the role of fault friction and orbital eccentricity in the development of ~45 km of right-lateral offset at Dardanus Sulcus and a possible case of <10 km of right-lateral offset at Tiamat Sulcus. We compute Coulomb failure conditions for these target fractures and consider tidal stress scenarios for both present eccentricity (0.0013) and possible past high (~0.05) eccentricity of Ganymede. We find that while diurnal stresses are not large enough to support strike-slip failure at present or past eccentricities, models that include both diurnal and NSR stress readily generate shear and normal stress magnitudes that could give rise to shear failure. Results for a past high eccentricity assuming a low coefficient of friction (μf = 0.2) suggest shear failure is possible down to depths of 1-2 km along both Dardanus and Tiamat. For a high coefficient of friction (μf = 0.6), failure is limited to about 1 km depth at Dardanus and Tiamat, although confined to small episodic slip windows for the latter. Moreover, our models predict a right-lateral sense of slip, in agreement with inferred offset observed at both regions. Based on these results, we infer that past shear failure on Ganymede is possible when NSR is a driving stress mechanism. We complement this study with a detailed morphological mapping of strike-slip morphologies (en echelon structures, strike-slip duplexes, laterally offset pre-existing features, and possible strained craters) at Nun Sulcus and several other locations. These structures serve as example regions to provide improved constraints for global stress mechanisms responsible for strike-slip fault evolution on Ganymede.
NASA Astrophysics Data System (ADS)
Grützner, Christoph; Campbell, Grace; Elliott, Austin; Walker, Richard; Abdrakhmatov, Kanatbek
2016-04-01
The Tien Shan and the Dzhungarian Ala-tau mountain ranges in Eastern Kazakhstan and China take up a significant portion of the total convergence between India and Eurasia, despite the fact that they are more than 1000 km away from the actual plate boundary. Shortening is accommodated by large thrust faults that strike more or less perpendicular to the convergence vector, and by a set of conjugate strike-slip faults. Some of these strike-slip faults are major features of several hundred kilometres length and have produced great historical earthquakes. In most cases, little is known about their slip-rates and earthquake history, and thus, about their role in the regional tectonic setting. This study deals with the NW-SE trending Dzhungarian Fault, a more than 350 km-long, right-lateral strike slip feature. It borders the Dzhungarian Ala-tau range and forms one edge of the so-called Dzhungarian Gate. The fault curves from a ~305° strike at its NW tip in Kazakhstan to a ~328° strike in China. No historical ruptures are known from the Kazakh part of the fault. A possible rupture in 1944 in the Chinese part remains discussed. We used remote sensing, Structure-from-Motion (SfM), differential GPS, field mapping, and Quaternary dating of offset geological markers in order to map the fault-related morphology and to measure the slip rate of the fault at several locations along strike. We also aimed to find out the age of the last surface rupturing earthquake and to determine earthquake recurrence intervals and magnitudes. We were further interested in the relation between horizontal and vertical motion along the fault and possible fault segmentation. Here we present first results from our 2015 survey. High-resolution digital elevation models of offset river terraces allowed us to determine the slip vector of the most recent earthquake. Preliminary dating results from abandoned fluvial terraces allow us to speculate on a late Holocene surface rupturing event. Morphological data indicate that more than one fault strand was activated in the Holocene. Folded river terraces testify to the amplitude of long-term deformation associated with the Dzhungarian Fault, but no dating results are available yet.
Choy, G.L.; Boatwright, J.
2004-01-01
Displacement, velocity, and velocity-squared records of P and SH body waves recorded at teleseismic distances are analyzed to determine the rupture characteristics of the Denali fault, Alaska, earthquake of 3 November 2002 (MW 7.9, Me 8.1). Three episodes of rupture can be identified from broadband (???0.1-5.0 Hz) waveforms. The Denali fault earthquake started as a MW 7.3 thrust event. Subsequent right-lateral strike-slip rupture events with centroid depths of 9 km occurred about 22 and 49 sec later. The teleseismic P waves are dominated by energy at intermediate frequencies (0.1-1 Hz) radiated by the thrust event, while the SH waves are dominated by energy at lower frequencies (0.05-0.2 Hz) radiated by the strike-slip events. The strike-slip events exhibit strong directivity in the teleseismic SH waves. Correcting the recorded P-wave acceleration spectra for the effect of the free surface yields an estimate of 2.8 ?? 1015 N m for the energy radiated by the thrust event. Correcting the recorded SH-wave acceleration spectra similarly yields an estimate of 3.3 ?? 10 16 N m for the energy radiated by the two strike-slip events. The average rupture velocity for the strike-slip rupture process is 1.1??-1.2??. The strike-slip events were located 90 and 188 km east of the epicenter. The rupture length over which significant or resolvable energy is radiated is, thus, far shorter than the 340-km fault length over which surface displacements were observed. However, the seismic moment released by these three events, 4 ?? 1020 N m, was approximately half the seismic moment determined from very low-frequency analyses of the earthquake. The difference in seismic moment can be reasonably attributed to slip on fault segments that did not radiate significant or coherent seismic energy. These results suggest that very large and great strike-slip earthquakes can generate stress pulses that rapidly produce substantial slip with negligible stress drop and little discernible radiated energy on fault segments distant from the initial point of nucleation. The existence of this energy-deficient rupture mode has important implications for the evaluation of the seismic hazard of very large strike-slip earthquakes.
NASA Technical Reports Server (NTRS)
Lundgren, Paul; Saucier, Fraancois; Palmer, Randy; Langon, Marc
1995-01-01
We compute crustal motions in Alaska by calculating the finite element solution for an elastic spherical shell problem. The method we use allows the finite element mesh to include faults and very long baseline interferometry (VLBI) baseline rates of change. Boundary conditions include Pacific-North American (PA-NA) plate motions. The solution is constrained by the oblique orientation of the Fairweather-Queen Charlotte strike-slip faults relative to the PA-NA relative motion direction and the oblique orientation from normal convergence of the eastern Aleutian trench fault systems, as well as strike-shp motion along the Denali and Totschunda fault systems. We explore the effects that a range of fault slip constraints and weighting of VLBI rates of change has on the solution. This allows us to test the motion on faults, such as the Denali fault, where there are conflicting reports on its present-day slip rate. We find a pattern of displacements which produce fault motions generally consistent with geologic observations. The motion of the continuum has the general pattern of radial movement of crust to the NE away from the Fairweather-Queen Charlotte fault systems in SE Alaska and Canada. This pattern of crustal motion is absorbed across the Mackenzie Mountains in NW Canada, with strike-slip motion constrained along the Denali and Tintina fault systems. In south central Alaska and the Alaska forearc oblique convergence at the eastern Aleutian trench and the strike-shp motion of the Denali fault system produce a counterclockwise pattern of motion which is partially absorbed along the Contact and related fault systems in southern Alaska and is partially extruded into the Bering Sea and into the forearc parallel the Aleutian trench from the Alaska Peninsula westward. Rates of motion and fault slip are small in western and northern Alaska, but the motions we compute are consistent with the senses of strike-slip motion inferred geologically along the Kaltag, Kobuk Trench, and Thompson Creek faults and with the normal faulting observed in NW Alaska near Nome. The nonrigid behavior of our finite element solution produces patterns of motion that would not have been expected from rigid block models: strike-slip faults can exist in a continuum that has motion mostly perpendicular to their strikes, and faults can exhibit along-strike differences in magnitudes and directions.
Intense hurricane strikes in southeastern New England since A.D. 1000
NASA Astrophysics Data System (ADS)
Donnelly, J. P.; Ettinger, R.; Cleary, P.
2001-05-01
Intense, category 3, 4, and 5 landfalling hurricanes pose a significant threat to lives and resources in coastal areas. Intense hurricane strikes also play a significant role in transporting sediments and shaping coastal landforms. Potential links between human-induced climate change and the frequency and intensity of tropical cyclones and the recent concentration of resources and population in areas where intense hurricanes may strike necessitate examination of decadal-to-millennial-scale variability in hurricane activity. The National Oceanic and Atmospheric Administration hurricane activity records for the western Atlantic Ocean only go back to the late 19th century. In the northeast United States historical records of hurricanes date back 370 years. We use stratigraphic evidence from coastal wetlands to extend the record of intense hurricane strikes into the prehistoric period in southeastern New England. Storm surge and wave action associated with intense storms can overtop barrier islands, remove sand and gravel from the beach and nearshore environment and deposit these sediments across the surface of coastal wetlands. In a regime of rising sea level, organic wetland sediments accumulate on top of these storm-induced deposits, preserving a record of past storms. We reconstructed storm deposition records within coastal marshes from eastern Connecticut to Cape Cod, Massachusetts. We matched these records to the historic record of storms and established the age of prehistoric storm deposits dating back about 1000 years with isotopic and stratigraphic dating techniques. The ages of storm deposits at all sites correlate to historic intense hurricane strikes. Prehistoric storm deposits can repeatedly be correlated among multiple sites and are of similar character and extent to the more recent deposits that we attribute to historic intense hurricane strikes. Therefore these older storm deposits were also likely deposited during prehistoric intense hurricanes. We documented at least eight deposits consistent with intense hurricane strikes in the last 1000 years. We identified deposits associated with historic intense hurricanes that occurred in A.D. 1954, 1938, 1869, 1815, 1638 and/or 1635. In addition we identified deposits likely associated with prehistoric intense hurricane strikes that occurred in A.D. 1400-1450, 1300-1400, and 1100-1150. These records indicate no apparent correlation between the frequency of intense hurricane landfalls in southeastern New England and the Little Ice Age and Medieval Warm Period climate oscillations.
Three-dimensional models of deformation near strike-slip faults
ten Brink, Uri S.; Katzman, Rafael; Lin, Jian
1996-01-01
We use three-dimensional elastic models to help guide the kinematic interpretation of crustal deformation associated with strike-slip faults. Deformation of the brittle upper crust in the vicinity of strike-slip fault systems is modeled with the assumption that upper crustal deformation is driven by the relative plate motion in the upper mantle. The driving motion is represented by displacement that is specified on the bottom of a 15-km-thick elastic upper crust everywhere except in a zone of finite width in the vicinity of the faults, which we term the “shear zone.” Stress-free basal boundary conditions are specified within the shear zone. The basal driving displacement is either pure strike slip or strike slip with a small oblique component, and the geometry of the fault system includes a single fault, several parallel faults, and overlapping en echelon faults. We examine the variations in deformation due to changes in the width of the shear zone and due to changes in the shear strength of the faults. In models with weak faults the width of the shear zone has a considerable effect on the surficial extent and amplitude of the vertical and horizontal deformation and on the amount of rotation around horizontal and vertical axes. Strong fault models have more localized deformation at the tip of the faults, and the deformation is partly distributed outside the fault zone. The dimensions of large basins along strike-slip faults, such as the Rukwa and Dead Sea basins, and the absence of uplift around pull-apart basins fit models with weak faults better than models with strong faults. Our models also suggest that the length-to-width ratio of pull-apart basins depends on the width of the shear zone and the shear strength of the faults and is not constant as previously suggested. We show that pure strike-slip motion can produce tectonic features, such as elongate half grabens along a single fault, rotated blocks at the ends of parallel faults, or extension perpendicular to overlapping en echelon faults, which can be misinterpreted to indicate a regional component of extension. Zones of subsidence or uplift can become wider than expected for transform plate boundaries when a minor component of oblique motion is added to a system of parallel strike-slip faults.
NASA Technical Reports Server (NTRS)
Livermore, S. F. (Inventor)
1978-01-01
An apparatus for measuring the intensity of current produced in an elongated electrical conductive member by a lightning strike for determining the intensity of the lightning strike is presented. The apparatus includes an elongated strip of magnetic material that is carried within an elongated tubular housing. A predetermined electrical signal is recorded along the length of said elongated strip of magnetic material. One end of the magnetic material is positioned closely adjacent to the electrically conductive member so that the magnetic field produced by current flowing through said electrically conductive member disturbs a portion of the recorded electrical signal directly proportional to the intensity of the lightning strike.
Air traffic controller lightning strike.
Spieth, M. E.; Kimura, R. L.; Schryer, T. D.
1994-01-01
Andersen Air Force Base in Guam boasts the tallest control tower in the Air Force. In 1986, an air traffic controller was struck by lightning as the bolt proceeded through the tower. Although he received only a backache, the lightning left a hole with surrounding scorch marks on his fatigue shirt and his undershirt. The lightning strike also ignited a portion of the field lighting panel, which caused the runway lights to go out immediately. Lack of a lightning rod is the most likely reason the controller was struck. Proper precautions against lightning strikes can prevent such occupational safety hazards. PMID:7966436
Properties of shoe insert materials related to shock wave transmission during gait.
Forner, A; García, A C; Alcántara, E; Ramiro, J; Hoyos, J V; Vera, P
1995-12-01
The influence of the mechanical characteristics of certain insole materials in the generation and transmission of heel strike impacts while walking was studied. Three insole materials were selected according to their mechanical characteristics under heel strike impacts. The selection of materials has made it possible to distinguish the effect of rigidity and loss tangent in the transmission of heel strike impacts. A lower rigidity and a high loss tangent have been shown to reduce the transmission of impacts to the tibia. A low rigidity was seen to significantly increase the transmission of impacts from tibia to forehead.
1999-02-01
articulated rotor systems, the rotor blade can deflect several feet and contact the fuselage of the helicopter, resulting in a "tunnel strike " in...tandem rotor configurations; or the tailboom, resulting in a "tailboom strike " in single rotor configurations. The H-46 Sea Knight, a tandem rotor...helicopter used by the U.S. Navy and Marines, has encountered over 100 tunnel strikes since 1964 and still occasionally experiences them. Most tunnel
Hill, David P.
2015-01-01
Accumulating evidence, although still strongly spatially aliased, indicates that although remote dynamic triggering of small-to-moderate (Mw<5) earthquakes can occur in all tectonic settings, transtensional stress regimes with normal and subsidiary strike-slip faulting seem to be more susceptible to dynamic triggering than transpressional regimes with reverse and subsidiary strike-slip faulting. Analysis of the triggering potential of Love- and Rayleigh-wave dynamic stresses incident on normal, reverse, and strike-slip faults assuming Andersonian faulting theory and simple Coulomb failure supports this apparent difference for rapid-onset triggering susceptibility.
Effects of 2D and 3D Error Fields on the SAS Divertor Magnetic Topology
NASA Astrophysics Data System (ADS)
Trevisan, G. L.; Lao, L. L.; Strait, E. J.; Guo, H. Y.; Wu, W.; Evans, T. E.
2016-10-01
The successful design of plasma-facing components in fusion experiments is of paramount importance in both the operation of future reactors and in the modification of operating machines. Indeed, the Small Angle Slot (SAS) divertor concept, proposed for application on the DIII-D experiment, combines a small incident angle at the plasma strike point with a progressively opening slot, so as to better control heat flux and erosion in high-performance tokamak plasmas. Uncertainty quantification of the error fields expected around the striking point provides additional useful information in both the design and the modeling phases of the new divertor, in part due to the particular geometric requirement of the striking flux surfaces. The presented work involves both 2D and 3D magnetic error field analysis on the SAS strike point carried out using the EFIT code for 2D equilibrium reconstruction, V3POST for vacuum 3D computations and the OMFIT integrated modeling framework for data analysis. An uncertainty in the magnetic probes' signals is found to propagate non-linearly as an uncertainty in the striking point and angle, which can be quantified through statistical analysis to yield robust estimates. Work supported by contracts DE-FG02-95ER54309 and DE-FC02-04ER54698.
Rearfoot striking runners are more economical than midfoot strikers.
Ogueta-Alday, Ana; Rodríguez-Marroyo, José Antonio; García-López, Juan
2014-03-01
This study aimed to analyze the influence of foot strike pattern on running economy and biomechanical characteristics in subelite runners with a similar performance level. Twenty subelite long-distance runners participated and were divided into two groups according to their foot strike pattern: rearfoot (RF, n = 10) and midfoot (MF, n = 10) strikers. Anthropometric characteristics were measured (height, body mass, body mass index, skinfolds, circumferences, and lengths); physiological (VO2max, anaerobic threshold, and running economy) and biomechanical characteristics (contact and flight times, step rate, and step length) were registered during both incremental and submaximal tests on a treadmill. There were no significant intergroup differences in anthropometrics, VO2max, or anaerobic threshold measures. RF strikers were 5.4%, 9.3%, and 5.0% more economical than MF at submaximal speeds (11, 13, and 15 km·h respectively, although the difference was not significant at 15 km·h, P = 0.07). Step rate and step length were not different between groups, but RF showed longer contact time (P < 0.01) and shorter flight time (P < 0.01) than MF at all running speeds. The present study showed that habitually rearfoot striking runners are more economical than midfoot strikers. Foot strike pattern affected both contact and flight times, which may explain the differences in running economy.
Foot strike pattern in preschool children during running: sex and shod-unshod differences.
Latorre-Román, Pedro Á; Párraga-Montilla, Juan A; Guardia-Monteagudo, Ignacio; García-Pinillos, Felipe
2018-04-01
This study aims to determine the foot strike patterns (FSPs) and neutral support (no inversion [INV]/eversion [EVE] and no foot rotation) in preschool children, as well as to determine the influence of shod/unshod conditions and sex. A total of 1356 children aged 3-6 years (673 boys and 683 girls) participated in this study. A sagittal and frontal-plane video (240 Hz) was recorded using a high-speed camcorder to record the following variables: rearfoot strike (RFS), midfoot strike (MFS), forefoot strike (FFS), inversion/ eversion (INV/EVE) and foot rotation on initial contact. There were no between-sex significant differences in both shod and unshod conditions in RFS. In the unshod condition, there was a significant reduction (p < 0.001) of RFS prevalence in both boys (shod condition = 44.2% vs. 34.7% unshod condition) and girls (shod condition = 48.5% vs. 36.1% unshod condition). As for neutral support, there were no between-sex differences in both shod and unshod conditions or in the shod-unshod comparison. In preschool children, no between-sex differences were found in relation to prevalence of RFS and neutral support (no INV/EVE). Shod running alters FSP of running barefoot, producing a significant increase of RFS prevalence.
Berger, B.R.; ,
2007-01-01
High-temperature, volcanic-centre-related hydrothermal systems involve large fluid-flow volumes and are observed to have high discharge rates in the order of 100-400 kg/s. The flows and discharge occur predominantly on networks of critically stressed fractures. The coupling of hydrothermal fluid flow with deformation produces the volumes of veins found in epithermal mineral deposits. Owing to this coupling, veins provide information on the fault-fracture architecture in existence at the time of mineralization. They therefore provide information on the nature of deformation within fault zones, and the relations between different fault sets. The Virginia City and Goldfield mining districts, Nevada, were localized in zones of strike-slip transtension in an Early to Mid-Miocene volcanic belt along the western margin of North America. The Camp Douglas mining area occurs within the same belt, but is localized in a zone of strike-slip transpression. The vein systems in these districts record the spatial evolution of strike-slip extensional and contractional stepovers, as well as geometry of faulting in and adjacent to points along strike-slip faults where displacement has been interrupted and transferred into releasing and restraining stepovers. ?? The Geological Society of London 2007.
NASA Astrophysics Data System (ADS)
Yin, J. J.; Chang, F.; Li, S. L.; Yao, X. L.; Sun, J. R.; Xiao, Y.
2017-10-01
According to the mathematical analysis model constructed on the basis of energy-balance relationship in lightning strike, and accompany with the simplified calculation strategy of composite resin pyrolysis degree dependent electrical conductivity, an effective three dimensional thermal-electrical coupling analysis finite element model of composite laminate suffered from lightning current was established based on ABAQUS, to elucidate the effects of lighting current waveform parameters and thermal/electrical properties of composite laminate on the extent of ablation damage. Simulated predictions agree well with the composite lightning strike directed effect experimental data, illustrating the potential accuracy of the constructed model. The analytical results revealed that extent of composite lightning strike ablation damage can be characterized by action integral validly, there exist remarkable power function relationships between action integral and visual damage area, projected damage area, maximum damage depth and damage volume of ablation damage, and enhancing the electrical conductivity and specific heat of composite, ablation damage will be descended obviously, power function relationships also exist between electrical conductivity, specific heat and ablation damage, however, the impact of thermal conductivity on the extent of ablation damage is not notable. The conclusions obtained provide some guidance for composite anti-lightning strike structure-function integration design.
High tsunami frequency as a result of combined strike-slip faulting and coastal landslides
Hornbach, Matthew J.; Braudy, Nicole; Briggs, Richard W.; Cormier, Marie-Helene; Davis, Marcy B.; Diebold, John B.; Dieudonne, Nicole; Douilly, Roby; Frohlich, Cliff; Gulick, Sean P.S.; Johnson, Harold E.; Mann, Paul; McHugh, Cecilia; Ryan-Mishkin, Katherine; Prentice, Carol S.; Seeber, Leonardo; Sorlien, Christopher C.; Steckler, Michael S.; Symithe, Steeve Julien; Taylor, Frederick W.; Templeton, John
2010-01-01
Earthquakes on strike-slip faults can produce devastating natural hazards. However, because they consist predominantly of lateral motion, these faults are rarely associated with significant uplift or tsunami generation. And although submarine slides can generate tsunami, only a few per cent of all tsunami are believed to be triggered in this way. The 12 January Mw 7.0 Haiti earthquake exhibited primarily strike-slip motion but nevertheless generated a tsunami. Here we present data from a comprehensive field survey that covered the onshore and offshore area around the epicentre to document that modest uplift together with slope failure caused tsunamigenesis. Submarine landslides caused the most severe tsunami locally. Our analysis suggests that slide-generated tsunami occur an order-of-magnitude more frequently along the Gonave microplate than global estimates predict. Uplift was generated because of the earthquake's location, where the Caribbean and Gonave microplates collide obliquely. The earthquake also caused liquefaction at several river deltas that prograde rapidly and are prone to failure. We conclude that coastal strike-slip fault systems such as the Enriquillo-Plantain Garden fault produce relief conducive to rapid sedimentation, erosion and slope failure, so that even modest predominantly strike-slip earthquakes can cause potentially catastrophic slide-generated tsunami - a risk that is underestimated at present.
NASA Astrophysics Data System (ADS)
Lin, A.; Rao, G.; Jia, D.; Wu, X.; Yan, B.; Ren, Z.
2010-12-01
The magnitude (Mw) 6.9 (Ms 7.1) Yushu earthquake occurred on 14 April 2010 in the Yushu area, central Tibetan Plateau, killing approximately 3000 people (including 270 missing) and causing widespread damage in the high mountain regions of the central Tibetan Plateau. The Yushu earthquake is comparable with the 1997 Mw 7.6 Manyi earthquake, the 2001 Mw 7.8 Kunlun earthquake, and the 2008 Mw 7.9 Wenchuan earthquake, which all occurred in the northern and eastern Tibetan Plateau, in terms of their magnitude and seismotectonic environment, related to the eastward extrusion of the Tibetan Plateau in response to continental collision between the Indian and Eurasian plates. Although some prompt reports related to ground deformation and the focal mechanism were published in the Chinese literature soon after the Yushu earthquake, there are scarce data related to the nature of co-seismic strike-slip rupturing structures and displacement distributions because the co-seismic surface ruptures were produced mainly in remote, high mountain regions of the Tibetan Plateau (average elevation >4000 m) and roads to the epicentral area were damaged, which made it difficult to gain access to the area and to undertake fieldwork immediately after the earthquake. Field investigations reveal that the earthquake produced a 33-km-long surface rupture zone, with dominantly left-lateral strike-slip along the Yushu Fault of the pre-existing strike-slip Ganzi-Yushu Fault Zone. The co-seismic surface ruptures are characterized by discontinuous shear faults, right-stepping en echelon tensional cracks, and left-stepping mole track structures that indicate a left-lateral strike-slip shear sense for the seismic fault. Field measurements indicate co-seismic left-lateral strike-slip displacements of approximately 0.3-3.2 m (typically 1-2 m), accompanied by a minor vertical component of <0.6 m. The present results show that (i) the Yushu earthquake occurred upon the pre-existing active Ganzi-Yushu Fault Zone, which controlled the spatial distribution of co-seismic surface ruptures and displacements; (ii) the left-lateral strike-slip motion indicates that the Ganzi-Yushu Fault Zone partitions deformation into eastward extrusion and northeastward shortening of the central Tibetan Plateau to accommodate the continuing penetration of the Indian plate into the Eurasian plate. Our findings confirm that present-day strain energy related to continental deformation in the central Tibetan Plateau, generated by collision between the Indian and Eurasian plates, is mainly released by strike-slip faulting along active strike-slip faults, and that the Ganzi-Yushu Fault Zone plays an important role in this crustal deformation, generating strong earthquakes that help to release the accumulated strain energy.
Foot strike patterns of runners at the 15-km point during an elite-level half marathon.
Hasegawa, Hiroshi; Yamauchi, Takeshi; Kraemer, William J
2007-08-01
There are various recommendations by many coaches regarding foot landing techniques in distance running that are meant to improve running performance and prevent injuries. Several studies have investigated the kinematic and kinetic differences between rearfoot strike (RFS), midfoot strike (MFS), and forefoot strike (FFS) patterns at foot landing and their effects on running efficiency on a treadmill and over ground conditions. However, little is known about the actual condition of the foot strike pattern during an actual road race at the elite level of competition. The purpose of the present study was to document actual foot strike patterns during a half marathon in which elite international level runners, including Olympians, compete. Four hundred fifteen runners were filmed by 2 120-Hz video cameras in the height of 0.15 m placed at the 15.0-km point and obtained sagittal foot landing and taking off images for 283 runners. Rearfoot strike was observed in 74.9% of all analyzed runners, MFS in 23.7%, and FFS in 1.4%. The percentage of MFS was higher in the faster runners group, when all runners were ranked and divided into 50 runner groups at the 15.0-km point of the competition. In the top 50, which included up to the 69th place runner in actual order who passed the 15-km point at 45 minutes, 53 second (this speed represents 5.45 m x s(-1), or 15 minutes, 17 seconds per 5 km), RFS, MFS, and FFS were 62.0, 36.0, and 2.0%, respectively. Contact time (CT) clearly increased for the slower runners, or the placement order increased (r = 0.71, p < or = 0.05). The CT for RFS + FFS for every 50 runners group significantly increased with increase of the placement order. The CT for RFS was significantly longer than MFS + FFS (200.0 +/- 21.3 vs. 183.0 +/- 16 millisecond). Apparent inversion (INV) of the foot at the foot strike was observed in 42% of all runners. The percentage of INV for MFS was higher than for RFS and FFS (62.5, 32.0, and 50%, respectively). The CT with INV for MFS + FFS was significantly shorter than the CT with and without INV for RFS. Furthermore, the CT with INV was significantly shorter than push-off time without INV for RFS. The findings of this study indicate that foot strike patterns are related to running speed. The percentage of RFS increases with the decreasing of the running speed; conversely, the percentage of MFS increases as the running speed increases. A shorter contact time and a higher frequency of inversion at the foot contact might contribute to higher running economy.
Protecting Your Park When Lightning Strikes.
ERIC Educational Resources Information Center
Frydenlund, Marvin M.
1987-01-01
A formula for assessing specific risk of lightning strikes is provided. Recent legal cases are used to illustrate potential liability. Six actions park managers can take to minimize danger from lightning are presented, and commonsense rules which should be publicly posted are listed. (MT)
NASA Astrophysics Data System (ADS)
Prejean, Stephanie; Ellsworth, William; Zoback, Mark; Waldhauser, Felix
2002-12-01
We have determined high-resolution hypocenters for 45,000+ earthquakes that occurred between 1980 and 2000 in the Long Valley caldera area using a double-difference earthquake location algorithm and routinely determined arrival times. The locations reveal numerous discrete fault planes in the southern caldera and adjacent Sierra Nevada block (SNB). Intracaldera faults include a series of east/west-striking right-lateral strike-slip faults beneath the caldera's south moat and a series of more northerly striking strike-slip/normal faults beneath the caldera's resurgent dome. Seismicity in the SNB south of the caldera is confined to a crustal block bounded on the west by an east-dipping oblique normal fault and on the east by the Hilton Creek fault. Two NE-striking left-lateral strike-slip faults are responsible for most seismicity within this block. To understand better the stresses driving seismicity, we performed stress inversions using focal mechanisms with 50 or more first motions. This analysis reveals that the least principal stress direction systematically rotates across the studied region, from NE to SW in the caldera's south moat to WNW-ESE in Round Valley, 25 km to the SE. Because WNW-ESE extension is characteristic of the western boundary of the Basin and Range province, caldera area stresses appear to be locally perturbed. This stress perturbation does not seem to result from magma chamber inflation but may be related to the significant (˜20 km) left step in the locus of extension along the Sierra Nevada/Basin and Range province boundary. This implies that regional-scale tectonic processes are driving seismic deformation in the Long Valley caldera.
Prejean, Stephanie; Ellsworth, William L.; Zoback, Mark; Waldhauser, Felix
2002-01-01
We have determined high-resolution hypocenters for 45,000+ earthquakes that occurred between 1980 and 2000 in the Long Valley caldera area using a double-difference earthquake location algorithm and routinely determined arrival times. The locations reveal numerous discrete fault planes in the southern caldera and adjacent Sierra Nevada block (SNB). Intracaldera faults include a series of east/west-striking right-lateral strike-slip faults beneath the caldera's south moat and a series of more northerly striking strike-slip/normal faults beneath the caldera's resurgent dome. Seismicity in the SNB south of the caldera is confined to a crustal block bounded on the west by an east-dipping oblique normal fault and on the east by the Hilton Creek fault. Two NE-striking left-lateral strike-slip faults are responsible for most seismicity within this block. To understand better the stresses driving seismicity, we performed stress inversions using focal mechanisms with 50 or more first motions. This analysis reveals that the least principal stress direction systematically rotates across the studied region, from NE to SW in the caldera's south moat to WNW-ESE in Round Valley, 25 km to the SE. Because WNW-ESE extension is characteristic of the western boundary of the Basin and Range province, caldera area stresses appear to be locally perturbed. This stress perturbation does not seem to result from magma chamber inflation but may be related to the significant (???20 km) left step in the locus of extension along the Sierra Nevada/Basin and Range province boundary. This implies that regional-scale tectonic processes are driving seismic deformation in the Long Valley caldera.
Kinematic Origins of Motor Inconsistency in Expert Pianists.
Tominaga, Kenta; Lee, André; Altenmüller, Eckart; Miyazaki, Fumio; Furuya, Shinichi
2016-01-01
For top performers, including athletes and musicians, even subtle inconsistencies in rhythm and force during movement production decrease the quality of performance. However, extensive training over many years beginning in childhood is unable to perfect dexterous motor performance so that it is without any error. To gain insight into the biological mechanisms underlying the subtle defects of motor actions, the present study sought to identify the kinematic origins of inconsistency of dexterous finger movements in musical performance. Seven highly-skilled pianists who have won prizes at international piano competitions played a short sequence of tones with the right hand at a predetermined tempo. Time-varying joint angles of the fingers were recorded using a custom-made data glove, and the timing and velocity of the individual keystrokes were recorded from a digital piano. Both ridge and stepwise multiple regression analyses demonstrated an association of the inter-trial variability of the inter-keystroke interval (i.e., rhythmic inconsistency) with both the rotational velocity of joints of the finger used for a keystroke (i.e., striking finger) and the movement independence between the striking and non-striking fingers. This indicates a relationship between rhythmic inconsistency in musical performance and the dynamic features of movements in not only the striking finger but also the non-striking fingers. In contrast, the inter-trial variability of the key-descending velocity (i.e., loudness inconsistency) was associated mostly with the kinematic features of the striking finger at the moment of the keystroke. Furthermore, there was no correlation between the rhythmic and loudness inconsistencies. The results suggest distinct kinematic origins of inconsistencies in rhythm and loudness in expert musical performance.
A new model for the initiation, crustal architecture, and extinction of pull-apart basins
NASA Astrophysics Data System (ADS)
van Wijk, J.; Axen, G. J.; Abera, R.
2015-12-01
We present a new model for the origin, crustal architecture, and evolution of pull-apart basins. The model is based on results of three-dimensional upper crustal numerical models of deformation, field observations, and fault theory, and answers many of the outstanding questions related to these rifts. In our model, geometric differences between pull-apart basins are inherited from the initial geometry of the strike-slip fault step which results from early geometry of the strike-slip fault system. As strike-slip motion accumulates, pull-apart basins are stationary with respect to underlying basement and the fault tips may propagate beyond the rift basin. Our model predicts that the sediment source areas may thus migrate over time. This implies that, although pull-apart basins lengthen over time, lengthening is accommodated by extension within the pull-apart basin, rather than formation of new faults outside of the rift zone. In this aspect pull-apart basins behave as narrow rifts: with increasing strike-slip the basins deepen but there is no significant younging outward. We explain why pull-apart basins do not go through previously proposed geometric evolutionary stages, which has not been documented in nature. Field studies predict that pull-apart basins become extinct when an active basin-crossing fault forms; this is the most likely fate of pull-apart basins, because strike-slip systems tend to straighten. The model predicts what the favorable step-dimensions are for the formation of such a fault system, and those for which a pull-apart basin may further develop into a short seafloor-spreading ridge. The model also shows that rift shoulder uplift is enhanced if the strike-slip rate is larger than the fault-propagation rate. Crustal compression then contributes to uplift of the rift flanks.
Bruening, Dustin A; Pohl, Michael B; Takahashi, Kota Z; Barrios, Joaquin A
2018-05-17
Changes in running strike pattern affect ankle and knee mechanics, but little is known about the influence of strike pattern on the joints distal to the ankle. The purpose of this study was to explore the effects of forefoot strike (FFS) and rearfoot strike (RFS) running patterns on foot kinematics and kinetics, from the perspectives of the midtarsal locking theory and the windlass mechanism. Per the midtarsal locking theory, we hypothesized that the ankle would be more inverted in early stance when using a FFS, resulting in decreased midtarsal joint excursions and increased dynamic stiffness. Associated with a more engaged windlass mechanism, we hypothesized that a FFS would elicit increased metatarsophalangeal joint excursions and negative work in late stance. Eighteen healthy female runners ran overground with both FFS and RFS patterns. Instrumented motion capture and a validated multi-segment foot model were used to analyze midtarsal and metatarsophalangeal joint kinematics and kinetics. During early stance in FFS the ankle was more inverted, with concurrently decreased midtarsal eversion (p < 0.001) and abduction excursions (p = 0.003) but increased dorsiflexion excursion (p = 0.005). Dynamic midtarsal stiffness did not differ (p = 0.761). During late stance in FFS, metatarsophalangeal extension was increased (p = 0.009), with concurrently increased negative work (p < 0.001). In addition, there was simultaneously increased midtarsal positive work (p < 0.001), suggesting enhanced power transfer in FFS. Clear evidence for the presence of midtarsal locking was not observed in either strike pattern during running. However, the windlass mechanism appeared to be engaged to a greater extent during FFS. Copyright © 2018 Elsevier Ltd. All rights reserved.
Almeida, Matheus O; Davis, Irene S; Lopes, Alexandre D
2015-10-01
Systematic review with meta-analysis. To determine the biomechanical differences between foot-strike patterns used when running. Strike patterns during running have received attention in the recent literature due to their potential mechanical differences and associated injury risks. Electronic databases (MEDLINE, Embase, LILACS, SciELO, and SPORTDiscus) were searched through July 2014. Studies (cross-sectional, case-control, prospective, and retrospective) comparing the biomechanical characteristics of foot-strike patterns during running in distance runners at least 18 years of age were included in this review. Two independent reviewers evaluated the risk of bias. A meta-analysis with a random-effects model was used to combine the data from the included studies. Sixteen studies were included in the final analysis. In the meta-analyses of kinematic variables, significant differences between forefoot and rearfoot strikers were found for foot and knee angle at initial contact and knee flexion range of motion. A forefoot-strike pattern resulted in a plantar-flexed ankle position and a more flexed knee position, compared to a dorsiflexed ankle position and a more extended knee position for the rearfoot strikers, at initial contact with the ground. In the comparison of rearfoot and midfoot strikers, midfoot strikers demonstrated greater ankle dorsiflexion range of motion and decreased knee flexion range of motion compared to rearfoot strikers. For kinetic variables, the meta-analysis revealed that rearfoot strikers had higher vertical loading rates compared to forefoot strikers. There are differences in kinematic and kinetic characteristics between foot-strike patterns when running. Clinicians should be aware of these characteristics to help in the management of running injuries and advice on training.
NASA Astrophysics Data System (ADS)
Muksin, Umar; Haberland, Christian; Nukman, Mochamad; Bauer, Klaus; Weber, Michael
2014-12-01
The Tarutung Basin is located at a right step-over in the northern central segment of the dextral strike-slip Sumatran Fault System (SFS). Details of the fault structure along the Tarutung Basin are derived from the relocations of seismicity as well as from focal mechanism and structural geology. The seismicity distribution derived by a 3D inversion for hypocenter relocation is clustered according to a fault-like seismicity distribution. The seismicity is relocated with a double-difference technique (HYPODD) involving the waveform cross-correlations. We used 46,904 and 3191 arrival differences obtained from catalogue data and cross-correlation analysis, respectively. Focal mechanisms of events were analyzed by applying a grid search method (HASH code). Although there is no significant shift of the hypocenters (10.8 m in average) and centroids (167 m in average), the application of the double difference relocation sharpens the earthquake distribution. The earthquake lineation reflects the fault system, the extensional duplex fault system, and the negative flower structure within the Tarutung Basin. The focal mechanisms of events at the edge of the basin are dominantly of strike-slip type representing the dextral strike-slip Sumatran Fault System. The almost north-south striking normal fault events along extensional zones beneath the basin correlate with the maximum principal stress direction which is the direction of the Indo-Australian plate motion. The extensional zones form an en-echelon pattern indicated by the presence of strike-slip faults striking NE-SW to NW-SE events. The detailed characteristics of the fault system derived from the seismological study are also corroborated by structural geology at the surface.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Canavan, G.H.
Attack allocation optimizations produce stability indices for unsymmetrical forces that indicate significant regions of both stability and instability and that have their minimum values roughly when the two sides have equal forces. This note derives combined stability indices for unsymmetrical offensive force configurations. The indices are based on optimal allocations of offensive missiles between vulnerable missiles and value based on the minimization of first strike cost, which is done analytically. Exchanges are modeled probabalistically and their results are converted into first and second strike costs through approximations to the damage to the value target sets held at risk. The stabilitymore » index is the product of the ratio of first to second strike costs seen by the two sides. Optimal allocations scale directly on the opponent`s vulnerable missiles, inversely on one`s own total weapons, and only logarithmically on the attacker`s damage preference, kill probability, and relative target set. The defender`s allocation scales in a similar manner on the attacker`s parameters. First and second strike magnitudes increase roughly linearly for the side with greater forces and decrease linearly for the side with fewer. Conversely, the first and second strike magnitudes decrease for the side with greater forces and increase for the side with fewer. These trends are derived and discussed analytically. The resulting stability indices exhibit a minimum where the two sides have roughly equal forces. If one side has much larger forces than the other, his costs drop to levels low enough that he is relatively insensitive to whether he strikes first or second. These calculations are performed with the analytic attack allocation appropriate for moderate forces, so some differences could be expected for the largest of the forces considered.« less
NASA Astrophysics Data System (ADS)
Laó-Dávila, Daniel A.; Llerandi-Román, Pablo A.
2017-01-01
The Río Guanajibo fold-and-thrust belt (RGFT), composed of Cretaceous serpentinite and volcano-sedimentary rocks, represents the deformation front of a contractional event in SW Puerto Rico during the Paleogene. Previous studies inferred structural and stratigraphic relationships from poorly exposed outcrops. New road cuts exposed the Yauco (YF) and El Rayo Formations (ERF) providing insights on the deformation of the hanging wall and footwall. We described the nature and orientation of faults and folds and analyzed the kinematic indicators to characterize the deformation. The YF occurs in the hanging wall and shows a sequence of folded, medium-bedded mudstone and thinly bedded shale and sandstone. Major folds strike NW-SE and are gentle with steeply inclined axial planes and sub-horizontal fold axes. Minor folds are open with moderately inclined axial planes and gently to moderately inclined SE-plunging fold axes. NW-SE striking reverse and thrust faults cut layers and show movement to the SW. Steep left-lateral faults strike NW-SE and NE-SW, and smaller right-lateral strike-slip faults strike NNE-SSW. At the footwall, the ERF consists of bioclastic limestone and polymictic orthoconglomerates and paraconglomerates. Reverse and strike-slip faults cut along lithological contacts. Results suggest that the hanging wall and footwall accommodated strain along preexisting weaknesses, which are dependent on lithology and sedimentary structures. The kinematic analysis suggests that shortening in the NE-SW direction was partitioned between folding and interlayer shortening, accommodated by flexural slip, and reverse and left-lateral faults that resulted from contraction. The RGFT represents the Paleogene back arc deformation of a bivergent thrust system.
NASA Astrophysics Data System (ADS)
Heidarzadeh, Mohammad; Harada, Tomoya; Satake, Kenji; Ishibe, Takeo; Takagawa, Tomohiro
2017-12-01
The Wharton Basin, off southwest Sumatra, ruptured to a large intraplate left-lateral strike-slip Mw 7.8 earthquake on 2016 March 2. The epicentre was located ∼800 km to the south of another similar-mechanism intraplate Mw 8.6 earthquake in the same basin on 2012 April 11. Small tsunamis from these strike-slip earthquakes were registered with maximum amplitudes of 0.5-1.5 cm on DARTs and 1-19 cm on tide gauges for the 2016 event, and the respective values of 0.5-6 and 6-40 cm for the 2012 event. By using both teleseismic body waves and tsunami observations of the 2016 event, we obtained optimum slip models with rupture velocity (Vr) in the range of 2.8-3.6 km s-1 belonging to both EW and NS faults. While the EW fault plane cannot be fully ruled out, we chose the best model as the NS fault plane with a Vr of 3.6 km s-1, a maximum slip of 7.7 m and source duration of 33 s. The tsunami energy period bands were 4-15 and 7-24 min for the 2016 and 2012 tsunamis, respectively, reflecting the difference in source sizes. Seismicity in the Wharton Basin is dominated by large strike-slip events including the 2012 (Mw 8.6 and 8.2) and 2016 (Mw 7.8) events, indicating that these events are possible tsunami sources in the Wharton Basin. Cumulative number and cumulative seismic-moment curves revealed that most earthquakes are of strike-slip mechanisms and the largest seismic-moment is provided by the strike-slip earthquakes in this basin.
The 2016 Mihoub (north-central Algeria) earthquake sequence: Seismological and tectonic aspects
NASA Astrophysics Data System (ADS)
Khelif, M. F.; Yelles-Chaouche, A.; Benaissa, Z.; Semmane, F.; Beldjoudi, H.; Haned, A.; Issaadi, A.; Chami, A.; Chimouni, R.; Harbi, A.; Maouche, S.; Dabbouz, G.; Aidi, C.; Kherroubi, A.
2018-06-01
On 28 May 2016 at 23:54 (UTC), an Mw5.4 earthquake occurred in Mihoub village, Algeria, 60 km southeast of Algiers. This earthquake was the largest event in a sequence recorded from 10 April to 15 July 2016. In addition to the permanent national network, a temporary network was installed in the epicentral region after this shock. Recorded event locations allow us to give a general overview of the sequence and reveal the existence of two main fault segments. The first segment, on which the first event in the sequence was located, is near-vertical and trends E-W. The second fault plane, on which the largest event of the sequence was located, dips to the southeast and strikes NE-SW. A total of 46 well-constrained focal mechanisms were calculated. The events located on the E-W-striking fault segment show mainly right-lateral strike-slip (strike N70°E, dip 77° to the SSE, rake 150°). The events located on the NE-SW-striking segment show mainly reverse faulting (strike N60°E, dip 70° to the SE, rake 130°). We calculated the static stress change caused by the first event (Md4.9) of the sequence; the result shows that the fault plane of the largest event in the sequence (Mw5.4) and most of the aftershocks occurred within an area of increased Coulomb stress. Moreover, using the focal mechanisms calculated in this work, we estimated the orientations of the main axes of the local stress tensor ellipsoid. The results confirm previous findings that the general stress field in this area shows orientations aligned NNW-SSE to NW-SE. The 2016 Mihoub earthquake sequence study thus improves our understanding of seismic hazard in north-central Algeria.
Recent physician strike in Israel: a health system under stress?
2013-01-01
In 2011, a series of physician strikes in Israel followed eight months of unsuccessful negotiations with the government (Ministry of Health and the Ministry of Finance). Strikes by physicians may be a warning that all is not well in a health system and protestors have claimed that they signify a system failure. In contrast, others argue that strikes have been a feature of the Israeli health system from its inception and should not be a cause for alarm. This paper analyses the Israeli health system from the perspective of the strikers' demands using the World Health Organisation’s six health system building blocks as a framework, including: service delivery; health workforce; information; medical products, vaccines and technologies; leadership and governance; and financing. While we recognise that the immediate causes of the 2011 strikes were concerns about salaries and working conditions, we argue that a complex set of interacting factors underlie the strikers' demands, resonating with issues relating to five of the WHO building blocks. We argue that of the five, three are most significant and limit progress with all the others: a disgruntled health workforce, many of whom believe that striking is the only way to be heard; a lack of leadership by the government in understanding and responding to physicians' concerns; and a purported information insufficiency, manifest as a lack of critique and analysis that may have prevented those at the top from making a reliable diagnosis of the system’s problems. This paper argues that there are cracks within the Israeli health system but that these are not irresolvable. The Israeli health system is a relatively new and popular health system, but there are no grounds for complacency. PMID:23947638
Lightning Detection Efficiency Analysis Process: Modeling Based on Empirical Data
NASA Technical Reports Server (NTRS)
Rompala, John T.
2005-01-01
A ground based lightning detection system employs a grid of sensors, which record and evaluate the electromagnetic signal produced by a lightning strike. Several detectors gather information on that signal s strength, time of arrival, and behavior over time. By coordinating the information from several detectors, an event solution can be generated. That solution includes the signal s point of origin, strength and polarity. Determination of the location of the lightning strike uses algorithms based on long used techniques of triangulation. Determination of the event s original signal strength relies on the behavior of the generated magnetic field over distance and time. In general the signal from the event undergoes geometric dispersion and environmental attenuation as it progresses. Our knowledge of that radial behavior together with the strength of the signal received by detecting sites permits an extrapolation and evaluation of the original strength of the lightning strike. It also limits the detection efficiency (DE) of the network. For expansive grids and with a sparse density of detectors, the DE varies widely over the area served. This limits the utility of the network in gathering information on regional lightning strike density and applying it to meteorological studies. A network of this type is a grid of four detectors in the Rondonian region of Brazil. The service area extends over a million square kilometers. Much of that area is covered by rain forests. Thus knowledge of lightning strike characteristics over the expanse is of particular value. I have been developing a process that determines the DE over the region [3]. In turn, this provides a way to produce lightning strike density maps, corrected for DE, over the entire region of interest. This report offers a survey of that development to date and a record of present activity.
The 2013, Mw 7.7 Balochistan earthquake, energetic strike-slip reactivation of a thrust fault
NASA Astrophysics Data System (ADS)
Avouac, Jean-Philippe; Ayoub, Francois; Wei, Shengji; Ampuero, Jean-Paul; Meng, Lingsen; Leprince, Sebastien; Jolivet, Romain; Duputel, Zacharie; Helmberger, Don
2014-04-01
We analyse the Mw 7.7 Balochistan earthquake of 09/24/2013 based on ground surface deformation measured from sub-pixel correlation of Landsat-8 images, combined with back-projection and finite source modeling of teleseismic waveforms. The earthquake nucleated south of the Chaman strike-slip fault and propagated southwestward along the Hoshab fault at the front of the Kech Band. The rupture was mostly unilateral, propagated at 3 km/s on average and produced a 200 km surface fault trace with purely strike-slip displacement peaking to 10 m and averaging around 6 m. The finite source model shows that slip was maximum near the surface. Although the Hoshab fault is dipping by 45° to the North, in accordance with its origin as a thrust fault within the Makran accretionary prism, slip was nearly purely strike-slip during that earthquake. Large seismic slip on such a non-optimally oriented fault was enhanced possibly due to the influence of the free surface on dynamic stresses or to particular properties of the fault zone allowing for strong dynamic weakening. Strike-slip faulting on thrust fault within the eastern Makran is interpreted as due to eastward extrusion of the accretionary prism as it bulges out over the Indian plate. Portions of the Makran megathrust, some thrust faults in the Kirthar range and strike-slip faults within the Chaman fault system have been brought closer to failure by this earthquake. Aftershocks cluster within the Chaman fault system north of the epicenter, opposite to the direction of rupture propagation. By contrast, few aftershocks were detected in the area of maximum moment release. In this example, aftershocks cannot be used to infer earthquake characteristics.
Exploiting Science: Enhancing the Safety Training of Pilots to Reduce the Risk of Bird Strikes
NASA Astrophysics Data System (ADS)
Mendonca, Flavio A. C.
Analysis of bird strikes to aviation in the U.S. from 1990 to 2015 indicate that the successful mitigation efforts at airports, which must be sustained, have reduced incidents with damage and a negative effect-on-flight since 2000. However, such efforts have done little to reduce strikes outside the airport jurisdiction, such as occurred with US Airways Flight 1549 in 2009. There are basically three strategies to mitigate the risk of bird strikes: standards set by aviation authorities, technology, and actions by crewmembers. Pilots play an important role as stakeholders in the prevention of bird strikes, especially outside the airport environment. Thus, safety efforts require enhanced risk management and aeronautical decision-making training for flight crews. The purpose of this study was to determine if a safety training protocol could effectively enhance CFR Part 141 general aviation pilots' knowledge and skills to reduce the risk of bird strikes to aviation. Participants were recruited from the Purdue University professional flight program and from Purdue Aviation. The researcher of this study used a pretest posttest experimental design. Additionally, qualitative data were collected through open-ended questions in the pretest, posttest, and a follow-up survey questionnaire. The participants' pretest and posttest scores were analyzed using parametric and nonparametric tests. Results indicated a significant increase in the posttest scores of the experimental group. An investigation of qualitative data showed that the topic "safety management of bird hazards by pilots" is barely covered during the ground and flight training of pilots. Furthermore, qualitative data suggest a misperception of the safety culture tenets and a poor familiarity with the safety risk management process regarding bird hazards. Finally, the researcher presented recommendations for practice and future research.
Home-to-work trips during the transportation strikes in Ile-de-France at the end of 1995
DOT National Transportation Integrated Search
1998-10-01
In November and December 1995, the region of Ile-de- France experienced strikes resulting in a virtually complete interruption of public transport. During this period, a majority of economic activity continued. The Direction Rigionale de Iquipement (...
What to Expect During a Teachers' Strike.
ERIC Educational Resources Information Center
Long, Jerri
1987-01-01
This two-page table charts the range of union activities, their adversarial intent, and possible administrative counterstrategies during a typical teacher strike. Twenty-four activities are covered, from peaceful demonstrations (like picketing), marches, and candlelight vigils, to harassments like nails in tires and telephone threats. (MLH)
Principles Governing the Mechanics and Control of Snake Strikes
2015-06-26
Zoo Atlanta. In this exploratory project we will monitor kinematics, ground reaction forces and strike forces in snakes to gain insight into common...species once Zoo Atlanta is again open for research collaboration; their renovation and expansion of herpetological facility has limited our
Federal Register 2010, 2011, 2012, 2013, 2014
2012-11-15
... recently approved certain products to trade at $0.50 and $1 strike price intervals on CBOE within exactly... Short Term Option Series (``STOS'') Program that normally trade in $1 Strike Price Intervals shall be [[Page 68173
DOT National Transportation Integrated Search
2016-12-01
Certain areas of Florida experience some of the highest densities of lightning strikes in the U.S. This has serious implications for the many electrical installations which the Florida Department of Transportation (FDOT) maintains along state roadway...
A Fossilized Energy Distribution of Lightning.
Pasek, Matthew A; Hurst, Marc
2016-07-28
When lightning strikes soil, it may generate a cylindrical tube of glass known as a fulgurite. The morphology of a fulgurite is ultimately a consequence of the energy of the lightning strike that formed it, and hence fulgurites may be useful in elucidating the energy distribution frequency of cloud-to-ground lightning. Fulgurites from sand mines in Polk County, Florida, USA were collected and analyzed to determine morphologic properties. Here we show that the energy per unit length of lightning strikes within quartz sand has a geometric mean of ~1.0 MJ/m, and that the distribution is lognormal with respect to energy per length and frequency. Energy per length is determined from fulgurites as a function of diameter, and frequency is determined both by cumulative number and by cumulative length. This distribution parallels those determined for a number of lightning parameters measured in actual atmospheric discharge events, such as charge transferred, voltage, and action integral. This methodology suggests a potential useful pathway for elucidating lightning energy and damage potential of strikes.
A Fossilized Energy Distribution of Lightning
Pasek, Matthew A.; Hurst, Marc
2016-01-01
When lightning strikes soil, it may generate a cylindrical tube of glass known as a fulgurite. The morphology of a fulgurite is ultimately a consequence of the energy of the lightning strike that formed it, and hence fulgurites may be useful in elucidating the energy distribution frequency of cloud-to-ground lightning. Fulgurites from sand mines in Polk County, Florida, USA were collected and analyzed to determine morphologic properties. Here we show that the energy per unit length of lightning strikes within quartz sand has a geometric mean of ~1.0 MJ/m, and that the distribution is lognormal with respect to energy per length and frequency. Energy per length is determined from fulgurites as a function of diameter, and frequency is determined both by cumulative number and by cumulative length. This distribution parallels those determined for a number of lightning parameters measured in actual atmospheric discharge events, such as charge transferred, voltage, and action integral. This methodology suggests a potential useful pathway for elucidating lightning energy and damage potential of strikes. PMID:27466230
Brazilian physicians hold national strike against medical insurance companies.
Falavigna, Asdrubal; da Silva, Pedro Guarise
2012-01-01
The Brazilian Health System has two different forms of access, public and private. The purpose of the public health system is to provide universal, complete access, free of charge, for the entire population. The private sector is composed by people who have private insurance. Nowadays, about 43 million Brazilians, or 26.3% of the population, have private health insurance. The main motivations of the physicians for the strike were the low payment for medical services and the constant interference of the private health insurance companies in medical autonomy. For this reason, Brazilian physicians held a 24-hour strike against the Medical Insurance Companies that did not accept to negotiate new fees in almost all Brazilian states. At least 120,000 physicians from all specialties stopped elective activities during that day, only providing urgent or emergency care. It is estimated that the strike affected 25 to 35 million Brazilians, about 76% of the total number of medical insurance users. Copyright © 2012 Elsevier Inc. All rights reserved.
Follow-on cable coupling lightning test, volume 1
NASA Technical Reports Server (NTRS)
Danforth, Richard
1990-01-01
A redesigned solid rocket motor test article was subjected to simulated lightning strikes. This test was performed to evaluate the effects of lightning strike to the redesigned motor and Space Transportation System. The purpose of the test was to evaluate the performance of systems tunnel design changes when subjected to the lightning discharges. The goal of the design changes was to reduce lightning induced coupling to cables within the systems tunnel. The test article was subjected to several different amounts and kinds of discharges. Changes in coupling levels detected during the tests are recorded. The dominant mode of coupling appears to be caused by the diffusion of the magnetic fields through the system tunnel covers. The results from bond strap integrity testing showed that 16 of 18 bond straps survived. Design change evaluations showed that coupling reduction ranged from 0 to 36 decibels for each type of cable. The type of cable has less effect on coupling than does strike location and strike levels. Recommendations for design changes are made.
Structural evolution of the Ural-Tian Shan junction: A view from Karatau ridge, South Kazakhstan
Alexeiev, D.V.; Cook, H.E.; Buvtyshkin, V.M.; Golub, L.Y.
2009-01-01
The deformation history of the Late Palaeozoic Ural-Tian Shan junction is discussed for the example of the Karatau ridge in southern Kazakhstan. Three deformation events are recognized. The Late Carboniferous D1 event is characterized by Laramide-style thrust-and-fold structures on the southern margin of Kazakhstan with shortening in a NE-SW direction. The Latest Permian and Triassic D2 event is controlled by compression in an east-west direction, which reflects collisional deformation in the Urals. The main structures are submeridional folds and north-west-striking sinistral strike-slip faults. The Triassic D3 event with shortening in a north-south direction reflects collision of the Turan microcontinent against the southern margin of Kazakhstan. The main structures are north-west-striking dextral strike-slip faults. Our new data provides important clues for the reconstruction of pre-Cretaceous structures between the Urals and the Tian Shan. ?? 2008 Acad??mie des sciences.
NASA Astrophysics Data System (ADS)
Engelder, Terry; Haith, Benjamin F.; Younes, Amgad
2001-07-01
Some Alleghanian joints in black shales of the Geneseo and Middlesex Formations of the Catskill Delta complex, Finger Lakes district, New York, slipped horizontally up to 8 cm. Horizontal slip is measured by the offset of ENE-striking joints. Alleghanian joints striking 330-350° display a right-lateral slip with an average value of 1.9 cm, while joints striking 004-010° slip in the left-lateral sense with an average value of 1.3 cm. The maximum horizontal stress (SH) driving this slip falls between 350° and 004°, the orientation of local Alleghanian layer-parallel shortening as indicated by both disjunctive and pencil cleavage. By commonality of orientation, we infer that slip on Alleghanian joints is driven contemporaneously with layer-parallel shortening. If so, the offset ENE-striking joints predate the Alleghanian stress field. These observations mean that both pre-Alleghanian and early Alleghanian joints persist through a period of penetrative strain.
MUSIC for localization of thunderstorm cells
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mosher, J.C.; Lewis, P.S.; Rynne, T.M.
1993-12-31
Lightning represents an event detectable optically, electrically, and acoustically, and several systems are already in place to monitor such activity. Unfortunately, such detection of lightning can occur too late, since operations need to be protected in advance of the first lightning strike. Additionally, the bolt itself can traverse several kilometers before striking the ground, leaving a large region of uncertainty as to the center of the storm and its possible strike regions. NASA Kennedy Space Center has in place an array of electric field mills that monitor the (effectively) DC electric field. Prior to the first lightning strike, the surfacemore » electric fields rise as the storm generator within a thundercloud begins charging. Extending methods we developed for an analogous source localization problem in mangnetoencephalography, we present Cramer-Rao lower bounds and MUSIC scans for fitting a point-charge source model to the electric field mill data. Such techniques can allow for the identification and localization of charge centers in cloud structures.« less
NASA Astrophysics Data System (ADS)
Cox, R. T.; Hatcher, R. D., Jr.; Forman, S. L.; Gamble, E. D. S.; Warrell, K. F.
2017-12-01
The eastern Tennessee seismic zone (ETSZ) trends 045o from NE Alabama and NW Georgia through Tennessee to SE Kentucky, and seismicity is localized 5-26 km deep in the basement. The ETSZ is the second most seismically active region in North America east of the Rocky Mountains, although no historic earthquakes larger than Mw 4.8 have been recorded here. Late Quaternary paleoiseismic evidence suggests that the ETSZ is capable of M7+ earthquakes and that neotectonic faults may have significantly influenced the regional relief. We have identified an 80 km-long, 060o-trending corridor in eastern Tennessee that contains collinear northeast-striking thrust, strike-slip, and normal Quaternary faults with displacements of 1-2 m, herein termed the Dandridge-Vonore fault zone (DVFZ). French Broad River alluvium in the northeast DVFZ near Dandridge, TN, is displaced by a 050o-striking, SE-dipping thrust fault and by a set of related fissures that record at least two significant post 25 ka paleo-earthquakes. Southwest of Dandridge near Alcoa, TN, a 060o-striking, SE-dipping thrust fault cuts Little River alluvium and records two significant post-15 ka paleo-earthquakes. Farther southwest at Vonore, colluvium with alluvial cobbles is thrust >1 m by a 057o-striking, steeply SE-dipping fault that may also have a significant strike-slip component, and Little Tennessee River alluvium is dropped >2 m along a 070o- striking normal fault. The DVFZ partly overlaps and is collinear with a local trend of maximum seismicity that extends 30 km farther SW of the DVFZ (as currently mapped), for a total length of 110 km. The DVFZ is coincident with a steep gradient in S-wave velocities (from high velocity on the SE to low velocity on the NW) at mid-crustal depths of 20 to 24 km, consistent with a fault and source zone at hypocentral depths in the crystalline basement. Moreover, the DVFZ parallels the NW foot of Blue Ridge Mountains, and the sense of thrusting at all sites of Quaternary faulting in the DVFZ is consistent with uplift of the Blue Ridge.
Protest of doctors: a basic human right or an ethical dilemma
2014-01-01
Background Peaceful protests and strikes are a basic human right as stated in the United Nations’ universal declaration on human rights. But for doctors, their proximity to life and death and the social contract between a doctor and a patient are stated as the reasons why doctors are valued more than the ordinary beings. In Pakistan, strikes by doctors were carried out to protest against lack of service structure, security and low pay. This paper discusses the moral and ethical concerns pertaining to the strikes by medical doctors in the context of Pakistan. The author has carefully tried to balance the discussion about moral repercussions of strikes on patients versus the circumstances of doctors working in public sector hospitals of a developing country that may lead to strikes. Discussion Doctors are envisaged as highly respectable due to their direct link with human lives. Under Hippocrates oath, care of the patient is a contractual obligation for the doctors and is superior to all other responsibilities. From utilitarian perspective, doctors’ strikes are justifiable only if there is evidence of long term benefits to the doctors, patients and an improvement in service delivery. Despite that, it is hard to justify such benefits against the risks to the patients. Harms that may incur to the patients include: prolongation of sufferings, irreversible damage to health, delay in treatment, death, loss of work and waste of financial resources. In a system of socialized medicine, government owing to greater control over resources and important managerial decisions should assume greater responsibility and do justice to all stakeholders including doctors as well as patients. If a doctor is underpaid, has limited options for career growth and is forced to work excessively, then not only quality of medical care and ability to act in the best interests of patients is adversely affected, it may also lead to brain drain. Summary There is no single best answer against or in favor of doctors’ industrial action. The author calls for the debate and discussion to revitalize the understanding of the ethical predicaments of doctors’ strikes with patient care as the priority. PMID:24612947
Cimadoro, Giuseppe; Mahaffey, Ryan; Babault, Nicolas
2018-04-04
Muay Thai fighters strongly rely on the use of the roundhouse kick due to its effectiveness (i.e. power) and implications on the final score. Therefore, different striking tempos at full power are used during training as a method to enhance kicking power. However, the neuromuscular responses are unknown. Thus, the goal of this study was to investigate neuromuscular responses to a single bout of shorter (every second = H1) and longer (every 3s = H3) kick striking time intervals, measured with the countermovement jump (CMJ). Nine professional Muay Thai fighters participated in this randomized, cross-over trial. CMJs were measured on force plates before and after (post 0min, post 5min, post 10min, post 20min and post 30min) two striking (1set x 20reps) conditions (H1; H3). Although no difference was observed between H1 and H3 values, neuromuscular fatigue parameters displayed different patterns over time. CMJ height decreased immediately after H3 striking (P<0.05), whereas for H1 condition CMJ height decreased from post20 as compared to baseline (P<0.05). Peak force in H3 condition was significantly lower at post10, post20 and post30 as compared to baseline. For H1, peak force values were lower than baseline only at post30. Peak power was significantly lower than baseline for both middle kick procedures. A slight but significant increase was observed at post5 for H3 condition, but decreased further post10 and remained constant during subsequent tests. In contrast, for H1 condition peak power remained unaffected after post10, whereas it decreased post20 and post30 minutes only when compared to post0. Results showed that both kick striking modes provoke comparable neuromuscular fatigue but H3 condition showed the potential to induce post activation potentiation. Muay Thai and conditioning coaches should focus on hard striking with both long and slow pacing during specific heavy bag or pad work.
Using a Sound Field to Reduce the Risks of Bird-Strike: An Experimental Approach.
Swaddle, John P; Ingrassia, Nicole M
2017-07-01
Each year, billions of birds collide with large human-made structures, such as building, towers, and turbines, causing substantial mortality. Such bird-strike, which is projected to increase, poses risks to populations of birds and causes significant economic costs to many industries. Mitigation technologies have been deployed in an attempt to reduce bird-strike, but have been met with limited success. One reason for bird-strike may be that birds fail to pay adequate attention to the space directly in front of them when in level, cruising flight. A warning signal projected in front of a potential strike surface might attract visual attention and reduce the risks of collision. We tested this idea in captive zebra finches (Taeniopygia guttata) that were trained to fly down a long corridor and through an open wooden frame. Once birds were trained, they each experienced three treatments at unpredictable times and in a randomized order: a loud sound field projected immediately in front of the open wooden frame; a mist net (i.e., a benign strike surface) placed inside the wooden frame; and both the loud sound and the mist net. We found that birds slowed their flight approximately 20% more when the sound field was projected in front of the mist net compared with when the mist net was presented alone. This reduction in velocity would equate to a substantial reduction in the force of any collision. In addition to slowing down, birds increased the angle of attack of their body and tail, potentially allowing for more maneuverable flight. Concomitantly, the only cases where birds avoided the mist net occurred in the sound-augmented treatment. Interestingly, the sound field by itself did not demonstrably alter flight. Although our study was conducted in a limited setting, the alterations of flight associated with our sound field has implications for reducing bird-strike in nature and we encourage researchers to test our ideas in field trials. © The Author 2017. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.
NASA Astrophysics Data System (ADS)
Zuza, A. V.; Yin, A.; Lin, J. C.
2015-12-01
Parallel evenly-spaced strike-slip faults are prominent in the southern San Andreas fault system, as well as other settings along plate boundaries (e.g., the Alpine fault) and within continental interiors (e.g., the North Anatolian, central Asian, and northern Tibetan faults). In southern California, the parallel San Jacinto, Elsinore, Rose Canyon, and San Clemente faults to the west of the San Andreas are regularly spaced at ~40 km. In the Eastern California Shear Zone, east of the San Andreas, faults are spaced at ~15 km. These characteristic spacings provide unique mechanical constraints on how the faults interact. Despite the common occurrence of parallel strike-slip faults, the fundamental questions of how and why these fault systems form remain unanswered. We address this issue by using the stress shadow concept of Lachenbruch (1961)—developed to explain extensional joints by using the stress-free condition on the crack surface—to present a mechanical analysis of the formation of parallel strike-slip faults that relates fault spacing and brittle-crust thickness to fault strength, crustal strength, and the crustal stress state. We discuss three independent models: (1) a fracture mechanics model, (2) an empirical stress-rise function model embedded in a plastic medium, and (3) an elastic-plate model. The assumptions and predictions of these models are quantitatively tested using scaled analogue sandbox experiments that show that strike-slip fault spacing is linearly related to the brittle-crust thickness. We derive constraints on the mechanical properties of the southern San Andreas strike-slip faults and fault-bounded crust (e.g., local fault strength and crustal/regional stress) given the observed fault spacing and brittle-crust thickness, which is obtained by defining the base of the seismogenic zone with high-resolution earthquake data. Our models allow direct comparison of the parallel faults in the southern San Andreas system with other similar strike-slip fault systems, both on Earth and throughout the solar system (e.g., the Tiger Stripe Fractures on Enceladus).
NASA Astrophysics Data System (ADS)
van Wijk, J.; Axen, G.; Abera, R.
2017-11-01
We present a model for the origin, crustal architecture, and evolution of pull-apart basins. The model is based on results of three-dimensional upper crustal elastic models of deformation, field observations, and fault theory, and is generally applicable to basin-scale features, but predicts some intra-basin structural features. Geometric differences between pull-apart basins are inherited from the initial geometry of the strike-slip fault step-over, which results from the forming phase of the strike-slip fault system. As strike-slip motion accumulates, pull-apart basins are stationary with respect to underlying basement, and the fault tips propagate beyond the rift basin, increasing the distance between the fault tips and pull-apart basin center. Because uplift is concentrated near the fault tips, the sediment source areas may rejuvenate and migrate over time. Rift flank uplift results from compression along the flank of the basin. With increasing strike-slip movement the basins deepen and lengthen. Field studies predict that pull-apart basins become extinct when an active basin-crossing fault forms; this is the most likely fate of pull-apart basins, because basin-bounding strike-slip systems tend to straighten and connect as they evolve. The models show that larger length-to-width ratios with overlapping faults are least likely to form basin-crossing faults, and pull-apart basins with this geometry are thus most likely to progress to continental rupture. In the Gulf of California, larger length-to-width ratios are found in the southern Gulf, which is the region where continental breakup occurred rapidly. The initial geometry in the northern Gulf of California and Salton Trough at 6 Ma may have been one of widely-spaced master strike-slip faults (lower length-to-width ratios), which our models suggest inhibits continental breakup and favors straightening of the strike-slip system by formation of basin-crossing faults within the step-over, as began 1.2 Ma when the San Jacinto and Elsinore - Cerro Prieto fault systems formed.
NASA Astrophysics Data System (ADS)
Ge, C.; Liu, D.; Li, H.; Zheng, Y.; Pan, J.
2017-12-01
The Karakax strike-slip fault, located in northwest Tibet, is a mature deformation belt with a long-time evolutionary history, which is also active at present and plays an important role in the tectonic deformation of the northwestern Tibetan Plateau. Nowadays, most geologists consider that the Karakax fault is generally east-west striking along the Karakax river valley, and northwest striking until to the Tashkorgan in the Mazar area. However, an ENE-WSW fault was identified at the Mazar area, which sited at the bend of the Karakax fault, we named this fault as the Matar fault. Via the detailed geological survey, the similar geometry and kinematic characteristics were identified between the Karakax and Matar faults: (1) The similar fault zone scale(Karakax:90 300m; Matar:100 220m); (2) The similar preferred orientation (nearly EW) of the stretching lineations and foliations; (3) All the fault planes of the both faults have a high dip angle and is nearly EW striking; (4) Lots of ductile deformations, such as σ-type quartz rotational mortar, S-C fabric, symmetric drag fold and so on, indicated that the Matar fault is a right-lateral strike-slip and thrust fault during the early ductile deformation stage; (5) the deluvium, sheared by Matar fault, indicated that the Matar fault has already transformed into a left-lateral strike-slip fault during the later brittle deformation stage. All the above showed that the Matar fault has a similar geometry and kinematic characteristics with the Karakax fault, and the former is the probable the western extension of the latter. Moreover, the form of the Karakax-Matar fault may had an impact to the geomorphology of the west Kunlun-Pamir area, such as the strike of the moutains and faults. considering the age of west Kunlun mountains uplifting and Karakax fault activating, we regard that the Matar fault (the westward extension of Karakax fault) may contributes much in forming the modern geomorphology features of the west Kunlun-Pamir area.
Protest of doctors: a basic human right or an ethical dilemma.
Abbasi, Imran Naeem
2014-03-10
Peaceful protests and strikes are a basic human right as stated in the United Nations' universal declaration on human rights. But for doctors, their proximity to life and death and the social contract between a doctor and a patient are stated as the reasons why doctors are valued more than the ordinary beings. In Pakistan, strikes by doctors were carried out to protest against lack of service structure, security and low pay. This paper discusses the moral and ethical concerns pertaining to the strikes by medical doctors in the context of Pakistan. The author has carefully tried to balance the discussion about moral repercussions of strikes on patients versus the circumstances of doctors working in public sector hospitals of a developing country that may lead to strikes. Doctors are envisaged as highly respectable due to their direct link with human lives. Under Hippocrates oath, care of the patient is a contractual obligation for the doctors and is superior to all other responsibilities. From utilitarian perspective, doctors' strikes are justifiable only if there is evidence of long term benefits to the doctors, patients and an improvement in service delivery. Despite that, it is hard to justify such benefits against the risks to the patients. Harms that may incur to the patients include: prolongation of sufferings, irreversible damage to health, delay in treatment, death, loss of work and waste of financial resources.In a system of socialized medicine, government owing to greater control over resources and important managerial decisions should assume greater responsibility and do justice to all stakeholders including doctors as well as patients. If a doctor is underpaid, has limited options for career growth and is forced to work excessively, then not only quality of medical care and ability to act in the best interests of patients is adversely affected, it may also lead to brain drain. There is no single best answer against or in favor of doctors' industrial action. The author calls for the debate and discussion to revitalize the understanding of the ethical predicaments of doctors' strikes with patient care as the priority.
Remarkable rates of lightning strike mortality in Malawi.
Mulder, Monique Borgerhoff; Msalu, Lameck; Caro, Tim; Salerno, Jonathan
2012-01-01
Livingstone's second mission site on the shore of Lake Malawi suffers very high rates of consequential lightning strikes. Comprehensive interviewing of victims and their relatives in seven Traditional Authorities in Nkhata Bay District, Malawi revealed that the annual rate of consequential strikes was 419/million, more than six times higher than that in other developing countries; the rate of deaths from lightning was 84/million/year, 5.4 times greater than the highest ever recorded. These remarkable figures reveal that lightning constitutes a significant stochastic source of mortality with potential life history consequences, but it should not deflect attention away from the more prominent causes of mortality in this rural area.
Investigation of severe lightning strike incidents to two USAF F-106A aircraft
NASA Technical Reports Server (NTRS)
Plumer, J. A.
1981-01-01
The results of the inspection and analysis of two F-106A aircraft that were struck by separate lightning strikes within a few minutes of each other are presented. Each aircraft sustained severe lightning strikes to the pitot booms, resulting in extensive damage to the pitot heater power harness, number 8 ground wire, and lightning suppressors, but there was no damage to either aircraft's electrical or avionic systems. A simulated lightning current of 226 kA and 3.8 million A(2)*S was required to reproduce the damage to the ground wires in the radomes. Photographs and detailed assessments of the damage are included.
Yager, Thomas R.; Soto-Viruet, Yadira; Barry, James J.
2012-01-01
The recent labor disputes over wages and working conditions that have affected South Africa’s three leading platinum-group metal (PGM) producers have affected an industry already plagued by market pressures and labor unrest and raised the specter of constraints in the world’s supply of these metals. Although low demand for these metals in 2011 and 2012 helped to offset production losses of recent years, and particularly those losses caused by the strikes in 2012, a prolonged resumption of strikes could cause severe shortages of iridium, platinum, rhodium, ruthenium, and, to a lesser extent, palladium.
Comparative Effect of Orthosis Design on Functional Performance
2012-03-21
progresses forward from mid to terminal stance. This also allows forefoot loading during agility and running activities. The modular design allows...patient to adopt a midfoot strike , as the combination of a heel strike with the plantar flexed foot plate leads to knee hyperextension. On average
RCN asks: are you prepared to strike for better pay?
Mckew, Matthew
2017-04-19
The RCN has opened an online poll on whether members would strike over pay. Some 270,000 RCN members are being asked for their views on NHS pay, two weeks after governments in England, Scotland and Wales announced the latest below-inflation pay increases.
Wildlife strikes to civil aircraft in the United States, 1990-2007
DOT National Transportation Integrated Search
2008-06-01
This report presents a summary analysis of data from the FAAs National Wildlife Strike : Database for the 18-year period 1990 through 2007. Unless noted, all totals are for the : 17-year period, and percentages are of the total known. Because of t...
75 FR 42722 - Privacy Act of 1974; System of Records
Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-22
... Missile Cable Affairs Offices at missile bases reporting to Headquarters Air Global Strike Command... entry and replace with ``Director of Maintenance, Deputy Chief of Staff/Logistics, Headquarters United... Communications Branch, Headquarters Air Force Global Strike Command/A6ON, 414 Curtiss Road, Suite 227, Barksdale...
New insights into the tectonic evolution of the Boconó Fault, Mérida Andes, Venezuela
NASA Astrophysics Data System (ADS)
Backé, G.
2006-12-01
The Boconó fault is a major right-lateral strike-slip fault that cuts along strike the Mérida Andes in Venezuela. The uplift of this mountain range started in the Miocene as a consequence of the relative oblique convergence between two lithospheric units named the Maracaibo block to the northwest and the Guyana shield to the southeast. Deformation in the Mérida Andes is partitioned between a strike-slip component along the Boconó fault and shortening perpendicular to the belt. Distinctive features define the Boconó fault: it is shifted southward relative to the chain axis and it does not have a continuous and linear trace but is composed of several fault segments of different orientations striking N35°E to N65°E. Quaternary fault strike-slip motion has been evidenced by various independent studies. However, onset of the strike-slip motion, fault offset and geometry at depth remains a matter of debate. Our work, based on morphostructural analyses of satellite and digital elevation model imagery, provides new data on both the geometry and the tectonic evolution of this major structure. We argue that the Boconó fault affects only the upper crust and connects at depth to a décollement. Consequently, it can not be considered as a plate boundary. The Boconó fault does however form the boundary between two different tectonic areas in the central part of the Mérida Andes as revealed by the earthquake focal mechanisms. South of the Boconó fault, the focal mechanisms are mainly compressional and reverse oblique-slip in agreement with NW SE shortening in the foothills. North of the Boconó fault, extensional and strike-slip deformation dominates. Microtectonic measurements collected in the central part of the Boconó fault are characterized by polyphased tectonics. The dextral shearing along the fault is superimposed to reverse oblique-slip to reverse motion, showing that initiation of transcurrent movement is more likely to have occurred after a certain amount of shortening. The present day strain partitioning along the Mérida Andes seems to be younger than the rise of the chain and coeval with the initiation of right-lateral shearing along the Boconó fault, which would have then initiated in the Pliocene. The Mérida Andes can be therefore considered as a case study of the kinematic evolution of a major strike-slip fault.
NASA Astrophysics Data System (ADS)
Bonali, F. L.; Corazzato, C.; Tibaldi, A.
2012-06-01
We describe the relationships between Plio-Quaternary tectonics, palaeoseismicity and volcanism along the NW-trending Calama-Olacapato-El Toro (COT) lineament that crosses the Andean chain and the Puna Plateau and continues within the eastern Cordillera at about 24° S. We studied in detail the area from the Chile-Argentina border to a few km east of the San Antonio del Los Cobres village. Satellite and field data revealed the presence of seven Quaternary NW-striking normal left-lateral fault segments in the southeastern part of the studied area and of a Plio-Quaternary N-S-striking graben structure in the northwestern part. The NW-striking Chorrillos fault (CF) segment shows the youngest motions, of late Pleistocene age, being marked by several fault scarps, sag ponds and offset Quaternary deposits and landforms. Offset lavas of 0.78 ± 0.1 Ma to 0.2 ± 0.08 Ma indicate fault kinematics characterised by a pitch angle of 20° to 27° SE, a total net displacement of 31 to 63.8 m, and a slip-rate of 0.16 to 0.08 mm/yr. This fault segment is 32 km long and terminates to the northwest near a set of ESE-dipping thrust faults affecting Tertiary strata, while to the southeast it terminates 10 km further from San Antonio. In the westernmost part of the examined area, in Chile at altitudes > 4000 m, recent N-S-striking normal fault scarps depict the 5-km-wide and 10-km-long graben structure. Locally, fault pitches indicate left-lateral normal kinematics. These faults affect deposits up to ignimbrites of Plio-Quaternary age. Scarp heights are from a few metres to 24 m. Despite that this area is located along the trace of the COT strike-slip fault system, which is reported as a continuous structure from Chile to Argentina in the literature, no evidence of NW-striking Plio-Quaternary strike-slip structures is present here. A series of numerical models were also developed in an elastic half-space with uniform isotropic elastic properties using the Coulomb 3.1 code. We studied the stress changes caused by slip along the various Quaternary COT fault segments, showing that the last motions occurred along the CF might promote in the future further displacement along nearby fault segments located to the northwest. Furthermore, slip along the NW-striking fault segments imparts normal stress changes on the nearby Tuzgle volcano feeding system.
NASA Astrophysics Data System (ADS)
Azevedo, Marco C.; Alves, Tiago M.; Fonseca, Paulo E.; Moore, Gregory F.
2018-01-01
Previous studies have suggested predominant extensional tectonics acting, at present, on the Nankai Accretionary Prism (NAP), and following a parallel direction to the convergence vector between the Philippine Sea and Amur Plates. However, a complex set of thrusts, pop-up structures, thrust anticlines and strike-slip faults is observed on seismic data in the outer wedge of the NAP, hinting at a complex strain distribution across SE Japan. Three-dimensional (3D) seismic data reveal three main families of faults: (1) NE-trending thrusts and back-thrusts; (2) NNW- to N-trending left-lateral strike-slip faults; and (3) WNW-trending to E-W right-lateral strike-slip faults. Such a fault pattern suggests that lateral slip, together with thrusting, are the two major styles of deformation operating in the outer wedge of the NAP. Both styles of deformation reflect a transpressional tectonic regime in which the maximum horizontal stress is geometrically close to the convergence vector. This work is relevant because it shows a progressive change from faults trending perpendicularly to the convergence vector, to a broader partitioning of strain in the form of thrusts and conjugate strike-slip faults. We suggest that similar families of faults exist within the inner wedge of the NAP, below the Kumano Basin, and control stress accumulation and strain accommodation in this latter region.
Geologic map of the Bodie Hills, California and Nevada
John, David A.; du Bray, Edward A.; Box, Stephen E.; Vikre, Peter G.; Rytuba, James J.; Fleck, Robert J.; Moring, Barry C.
2015-01-01
The Bodie Hills covers about 1,200 km2 straddling the California-Nevada state boundary just north of Mono Lake in the western part of the Basin and Range Province, about 20 km east of the central Sierra Nevada. The area is mostly underlain by the partly overlapping, middle to late Miocene Bodie Hills volcanic field and Pliocene to late Pleistocene Aurora volcanic field (John and others, 2012). Upper Miocene to Pliocene sedimentary deposits, mostly basin-filling sediments, gravel deposits, and fanglomerates, lap onto the west, north, and east sides of the Bodie Hills, where they cover older Miocene volcanic rocks. Quaternary surficial deposits, including extensive colluvial, fluvial, glacial, and lacustrine deposits, locally cover all older rocks. Miocene and younger rocks are tilted ≤30° in variable directions. These rocks are cut by several sets of high-angle faults that exhibit a temporal change from conjugate northeast-striking left-lateral and north-striking right-lateral oblique-slip faults in rocks older than about 9 Ma to north- and northwest-striking dip-slip faults in late Miocene rocks. The youngest faults are north-striking normal and northeast-striking left-lateral oblique-slip faults that cut Pliocene-Pleistocene rocks. Numerous hydrothermal systems were active during Miocene magmatism and formed extensive zones of hydrothermally altered rocks and several large mineral deposits, including gold- and silver-rich veins in the Bodie and Aurora mining districts (Vikre and others, in press).
Effects of lightning on operations of aerospace vehicles
NASA Technical Reports Server (NTRS)
Fisher, Bruce D.
1989-01-01
Traditionally, aircraft lightning strikes were a major aviation safety issue. However, the increasing use of composite materials and the use of digital avionics for flight critical systems will require that more specific lightning protection measures be incorporated in the design of such aircraft in order to maintain the excellent lightning safety record presently enjoyed by transport aircraft. In addition, several recent lightning mishaps, most notably the loss of the Atlas/Centaur-67 vehicle at Cape Canaveral Air Force Station, Florida in March 1987, have shown the susceptibility of aircraft and launch vehicles to the phenomenon of vehicle-triggered lightning. The recent findings of the NASA Storm Hazards Program were reviewed as they pertain to the atmospheric conditions conducive to aircraft lightning strikes. These data are then compared to recent summaries of lightning strikes to operational aircraft fleets. Finally, the new launch commit criteria for triggered lightning being used by NASA and the U.S. Defense Department are summarized. The NASA Research data show that the greatest probability of a direct strike in a thunderstorm occurs at ambient temperatures of about -40 C. Relative precipitation and turbulence levels were characterized as negligible to light for these conditions. However, operational fleet data have shown that most aircraft lightning strikes in routine operations occur at temperatures near the freezing level in non-cumulonimbus clouds. The non-thunderstorm environment was not the subject of dedicated airborne lightning research.
Making inference from wildlife collision data: inferring predator absence from prey strikes
Hosack, Geoffrey R.; Barry, Simon C.
2017-01-01
Wildlife collision data are ubiquitous, though challenging for making ecological inference due to typically irreducible uncertainty relating to the sampling process. We illustrate a new approach that is useful for generating inference from predator data arising from wildlife collisions. By simply conditioning on a second prey species sampled via the same collision process, and by using a biologically realistic numerical response functions, we can produce a coherent numerical response relationship between predator and prey. This relationship can then be used to make inference on the population size of the predator species, including the probability of extinction. The statistical conditioning enables us to account for unmeasured variation in factors influencing the runway strike incidence for individual airports and to enable valid comparisons. A practical application of the approach for testing hypotheses about the distribution and abundance of a predator species is illustrated using the hypothesized red fox incursion into Tasmania, Australia. We estimate that conditional on the numerical response between fox and lagomorph runway strikes on mainland Australia, the predictive probability of observing no runway strikes of foxes in Tasmania after observing 15 lagomorph strikes is 0.001. We conclude there is enough evidence to safely reject the null hypothesis that there is a widespread red fox population in Tasmania at a population density consistent with prey availability. The method is novel and has potential wider application. PMID:28243534
Geology of the southernmost Piedmont from Columbus to Junction City, GA
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hanley, T.B.
1993-03-01
Mapping in the Piedmont from the Chattahoochee River to Junction City, GA, is critical to understanding contacts with Southern Appalachian outboard terranes, relationships to the Piedmont allochthon, strike slip displacements along major faults and late Paleozoic and post Paleozoic tectonic activity. Three major map units defining a large synform are recognized in western Muscogee County: the North Columbus Migmatite Complex, the Moffitts Mill Schist (MMS), and the Phenix City gneiss. The distinctive but poorly exposed fine grained feldspar augen MMS, which extends at least as far east as Geneva, contains small enclaves of amphibolite and calcsilicate and large enclaves ofmore » lineated granitoid gneiss. Protomylonites and mylonitic gneiss with a N-S to N45E strike are exposed from Geneva to Junction City. Three brecciated quartz dikes transect the area in eastern Muscogee Co. and Talbot Co., converging on Talbotton from the southwest. The northern dike strikes ENE and is associated with an augen schist; the middle dike strikes NE and projects to the southwest deep into Muscogee County as a silicified fracture zone with minor associated granite. The southern dike has a NNE strike and is parallel to and locally silicifies the mylonitic foliation that dominates gneisses to the east. Deflections of the magnetic anomaly patterns to the northeast in the Geneva - Junction City area are parallel to quartz dikes and mylonitic foliations.« less
NASA Astrophysics Data System (ADS)
Fontaine, Fabrice J.; Cannat, Mathilde; Escartin, Javier; Crawford, Wayne C.
2014-07-01
processes and efficiency of hydrothermal heat extraction along the axis of mid-ocean ridges are controlled by lithospheric thermal and permeability structures. Hydrothermal circulation models based on the structure of fast and intermediate spreading ridges predict that hydrothermal cell organization and vent site distribution are primarily controlled by the thermodynamics of high-temperature mid-ocean ridge hydrothermal fluids. Using recent constraints on shallow structure at the slow spreading Lucky Strike segment along the Mid-Atlantic Ridge, we present a physical model of hydrothermal cooling that incorporates the specificities of a magma-rich slow spreading environment. Using three-dimensional numerical models, we show that, in contrast to the aforementioned models, the subsurface flow at Lucky Strike is primarily controlled by across-axis permeability variations. Models with across-axis permeability gradients produce along-axis oriented hydrothermal cells and an alternating pattern of heat extraction highs and lows that match the distribution of microseismic clusters recorded at the Lucky Strike axial volcano. The flow is also influenced by temperature gradients at the base of the permeable hydrothermal domain. Although our models are based on the structure and seismicity of the Lucky Strike segment, across-axis permeability gradients are also likely to occur at faster spreading ridges and these results may also have important implications for the cooling of young crust at fast and intermediate spreading centers.
Nowcasting of Lightning-Related Accidents in Africa
NASA Astrophysics Data System (ADS)
Ihrlich, Laura; Price, Colin
2016-04-01
Tropical Africa is the world capital of thunderstorm activity with the highest density of strikes per square kilometer per year. As a result it is also the continent with perhaps the highest casualties and injuries from direct lightning strikes. This region of the globe also has little lightning protection of rural homes and schools, while many casualties occur during outdoor activities (e.g. farming, fishing, sports, etc.) In this study we investigated two lightning-caused accidents that got wide press coverage: A lightning strike to a Cheetah Center in Namibia which caused a huge fire and great destruction (16 October 2013), and a plane crash in Mali where 116 people died (24 July 2014). Using data from the World Wide Lightning Location Network (WWLLN) we show that the lightning data alone can provide important early warning information that can be used to reduce risks and damages and loss of life from lightning strikes. We have developed a now-casting scheme that allows for early warnings across Africa with a relatively low false alarm rate. To verify the accuracy of our now-cast, we have performed some statistical analysis showing relatively high skill at providing early warnings (lead time of a few hours) based on lightning alone. Furthermore, our analysis can be used in forensic meteorology for determining if such accidents are caused by lightning strikes.
Instrumented sparring vest to aid in martial arts scoring.
Harrigan, Katie; Logan, Rachel; Sluti, Anne; Rogge, Renee
2006-01-01
Competitors in certain martial arts, such as Taekwondo, are required to wear protective vests during competition. This article outlines the design and fabrication of an instrumented martial arts sparring vest that will aid in martial arts scoring, which is currently a work in progress. After fabrication, this instrumented vest and associated system will not only provide the same protection as before modification, but will also report the location and force magnitude of strikes applied to the vest. This will aid in scoring of martial arts competitions, as it will determine if a strike is forceful enough to be considered deliberate and therefore is a valid point-scoring strike. This will make scoring of competitions unbiased and equal for all competitors, something that is difficult to achieve based solely on a judge's assessment by observation. The system will also indicate the probable injury resulting from a strike, for example, no injury, bruising or bone fracture. If a competitor's strike force is excessive and serious injury could result, the system will indicate this so action can be taken, such as penalty or disqualification of a competitor. Both tissue testing and force testing will be conducted prior to vest fabrication to determine estimates of forces that will damage tissue and typical forces experienced during competition. After testing is complete, the system will be fabricated and the testing results will be implemented into the associated software.
High tsunami frequency as a result of combined strike-slip faulting and coastal landslides
Hornbach, M.J.; Braudy, N.; Briggs, R.W.; Cormier, M.-H.; Davis, M.B.; Diebold, J.B.; Dieudonne, N.; Douilly, R.; Frohlich, C.; Gulick, S.P.S.; Johnson, H. E.; Mann, P.; McHugh, C.; Ryan-Mishkin, K.; Prentice, C.S.; Seeber, L.; Sorlien, C.C.; Steckler, M.S.; Symithe, S.J.; Taylor, F.W.; Templeton, J.
2010-01-01
Earthquakes on strike-slip faults can produce devastating natural hazards. However, because they consist predominantly of lateral motion, these faults are rarely associated with significant uplift or tsunami generation. And although submarine slides can generate tsunami, only a few per cent of all tsunami are believed to be triggered in this way. The 12 January Mw 7.0 Haiti earthquake exhibited primarily strike-slip motion but nevertheless generated a tsunami. Here we present data from a comprehensive field survey that covered the onshore and offshore area around the epicentre to document that modest uplift together with slope failure caused tsunamigenesis. Submarine landslides caused the most severe tsunami locally. Our analysis suggests that slide-generated tsunami occur an order-of-magnitude more frequently along the Gonave microplate than global estimates predict. Uplift was generated because of the earthquake?s location, where the Caribbean and Gonave microplates collide obliquely. The earthquake also caused liquefaction at several river deltas that prograde rapidly and are prone to failure. We conclude that coastal strike-slip fault systems such as the Enriquillog-Plantain Garden fault produce relief conducive to rapid sedimentation, erosion and slope failure, so that even modest predominantly strike-slip earthquakes can cause potentially catastrophic slide-generated tsunamig-a risk that is underestimated at present. ?? 2010 Macmillan Publishers Limited. All rights reserved.
NASA Astrophysics Data System (ADS)
Gasser, D.; Mancktelow, N. S.
2009-04-01
The Helvetic nappes in the Swiss Alps form a classic fold-and-thrust belt related to overall NNW-directed transport. In western Switzerland, the plunge of nappe fold axes and the regional distribution of units define a broad depression, the Rawil depression, between the culminations of Aiguilles Rouge massif to the SW and Aar massif to the NE. A compilation of data from the literature establishes that, in addition to thrusts related to nappe stacking, the Rawil depression is cross-cut by four sets of brittle faults: (1) SW-NE striking normal faults that strike parallel to the regional fold axis trend, (2) NW-SE striking normal faults and joints that strike perpendicular to the regional fold axis trend, and (3) WNW-ESE striking normal plus dextral oblique-slip faults as well as (4) WSW-ENE striking normal plus dextral oblique-slip faults that both strike oblique to the regional fold axis trend. We studied in detail a beautifully exposed fault from set 3, the Rezli fault zone (RFZ) in the central Wildhorn nappe. The RFZ is a shallow to moderately-dipping (ca. 30-60˚) fault zone with an oblique-slip displacement vector, combining both dextral and normal components. It must have formed in approximately this orientation, because the local orientation of fold axes corresponds to the regional one, as does the generally vertical orientation of extensional joints and veins associated with the regional fault set 2. The fault zone crosscuts four different lithologies: limestone, intercalated marl and limestone, marl and sandstone, and it has a maximum horizontal dextral offset component of ~300 m and a maximum vertical normal offset component of ~200 m. Its internal architecture strongly depends on the lithology in which it developed. In the limestone, it consists of veins, stylolites, cataclasites and cemented gouge, in the intercalated marls and limestones of anastomosing shear zones, brittle fractures, veins and folds, in the marls of anastomosing shear zones, pressure solution seams and veins and in the sandstones of coarse breccia and veins. Later, straight, sharp fault planes cross-cut all these features. In all lithologies, common veins and calcite-cemented fault rocks indicate the strong involvement of fluids during faulting. Today, the southern Rawil depression and the Rhone Valley belong to one of the seismically most active regions in Switzerland. Seismogenic faults interpreted from earthquake focal mechanisms strike ENE-WSW to WNW-ESE, with dominant dextral strike-slip and minor normal components and epicentres at depths of < 15 km. All three Neogene fault sets (2-4) could have been active under the current stress field inferred from the current seismicity. This implies that the same mechanisms that formed these fault zones in the past may still persist at depth. The Rezli fault zone allows the detailed study of a fossil fault zone that can act as a model for processes still occurring at deeper levels in this seismically active region.
Rheological structure of the lithosphere in plate boundary strike-slip fault zones
NASA Astrophysics Data System (ADS)
Chatzaras, Vasileios; Tikoff, Basil; Kruckenberg, Seth C.; Newman, Julie; Titus, Sarah J.; Withers, Anthony C.; Drury, Martyn R.
2016-04-01
How well constrained is the rheological structure of the lithosphere in plate boundary strike-slip fault systems? Further, how do lithospheric layers, with rheologically distinct behaviors, interact within the strike-slip fault zones? To address these questions, we present rheological observations from the mantle sections of two lithospheric-scale, strike-slip fault zones. Xenoliths from ˜40 km depth (970-1100 ° C) beneath the San Andreas fault system (SAF) provide critical constraints on the mechanical stratification of the lithosphere in this continental transform fault. Samples from the Bogota Peninsula shear zone (BPSZ, New Caledonia), which is an exhumed oceanic transform fault, provide insights on lateral variations in mantle strength and viscosity across the fault zone at a depth corresponding to deformation temperatures of ˜900 ° C. Olivine recrystallized grain size piezometry suggests that the shear stress in the SAF upper mantle is 5-9 MPa and in the BPSZ is 4-10 MPa. Thus, the mantle strength in both fault zones is comparable to the crustal strength (˜10 MPa) of seismogenic strike-slip faults in the SAF system. Across the BPSZ, shear stress increases from 4 MPa in the surrounding rocks to 10 MPa in the mylonites, which comprise the core of the shear zone. Further, the BPSZ is characterized by at least one order of magnitude difference in the viscosity between the mylonites (1018 Paṡs) and the surrounding rocks (1019 Paṡs). Mantle viscosity in both the BPSZ mylonites and the SAF (7.0ṡ1018-3.1ṡ1020 Paṡs) is relatively low. To explain our observations from these two strike-slip fault zones, we propose the "lithospheric feedback" model in which the upper crust and lithospheric mantle act together as an integrated system. Mantle flow controls displacement and the upper crust controls the stress magnitude in the system. Our stress data combined with data that are now available for the middle and lower crustal sections of other transcurrent fault systems support the prediction for constant shear strength (˜10 MPa) throughout the lithosphere; the stress magnitude is controlled by the shear strength of the upper crustal faults. Fault rupture in the upper crust induces displacement rate loading of the upper mantle, which in turn, causes strain localization in the mantle shear zone beneath the strike-slip fault. Such forced localization leads to higher stresses and strain rates in the shear zone compared to the surrounding rocks. Low mantle viscosity within the shear zone is critical for facilitating mantle flow, which induces widespread crustal deformation and displacement loading. The lithospheric feedback model suggests that strike-slip fault zones are not mechanically stratified in terms of shear stress, and that it is the time-dependent interaction of the different lithospheric layers - rather than their relative strengths - that governs the rheological behavior of the plate boundary, strike-slip fault zones.
ERIC Educational Resources Information Center
Selinger, Alphonse D.
1980-01-01
Ontario secondary teachers were more favorable in 1977 than 1974 towards collective bargaining but showed significantly less support for sanctions, especially striking. Still, if their interests were seriously threatened, they would strike. Teacher sex and length of Ontario residence were significant predictors of militancy. (Author/SB)
48 CFR 22.101-2 - Contract pricing and administration.
Code of Federal Regulations, 2010 CFR
2010-10-01
...-reimbursement contracts or for recognition of costs in pricing fixed-price contracts if they result in... organizations to settle disputes. (c) Strikes normally result in changing patterns of cost incurrence and... recognition of costs in pricing fixed-price contracts. Certain costs may increase because of strikes; e.g...
48 CFR 22.101-2 - Contract pricing and administration.
Code of Federal Regulations, 2011 CFR
2011-10-01
...-reimbursement contracts or for recognition of costs in pricing fixed-price contracts if they result in... organizations to settle disputes. (c) Strikes normally result in changing patterns of cost incurrence and... recognition of costs in pricing fixed-price contracts. Certain costs may increase because of strikes; e.g...
A Noninvasive Technique for Blocking Vomeronasal Chemoreception in Rattlesnakes
ERIC Educational Resources Information Center
Stark, C. Patrick; Chiszar, David; Smith, Hobart M.
2006-01-01
To examine the effects of vomeronasal deprivation on strike-induced chemosensory searching (SICS) in rattlesnakes we used a newly developed technique to anesthetize the vomeronasal organs. We compared rate of tongue flicking after striking prey in avomic rattlesnakes to vomic controls. Avomic rattlesnakes exhibited significantly fewer tongue…
Endgame Is Eyed in Chicago Strike
ERIC Educational Resources Information Center
Sawchuk, Stephen
2012-01-01
A strike last week by some 29,000 teachers in Chicago pushed long-simmering tensions over deeply divisive school improvement ideas--including changes in teacher evaluation and the takeover or closure of underperforming schools--into the national spotlight. A framework for a tentative agreement emerged last Friday, and the union's house of…
Teaching Striking/Fielding Concepts in Cricket
ERIC Educational Resources Information Center
Turner, Adrian P.
2004-01-01
This article presents activities for developing striking/fielding concepts in modified cricket games. Though not as familiar to American children, cricket is emerging as the second (to soccer) most popular game in the world. The novelty of the skills provides an appropriate learning challenge for all students while reinforcing concepts and…
Rocks in a Box: A Three-Point Problem.
ERIC Educational Resources Information Center
Leyden, Michael B.
1981-01-01
Describes a simulation drilling core activity involving the use of a physical model from which students gather data and solve a three-point problem to determine the strike and dip of a buried stratum. Includes descriptions of model making, data plots, and additional problems involving strike and dip. (DS)
How to protect a wind turbine from lightning
NASA Technical Reports Server (NTRS)
Dodd, C. W.; Mccalla, T., Jr.; Smith, J. G.
1983-01-01
Techniques for reducing the chances of lightning damage to wind turbines are discussed. The methods of providing a ground for a lightning strike are discussed. Then details are given on ways to protect electronic systems, generating and power equipment, blades, and mechanical components from direct and nearby lightning strikes.
When the Corporate Storm Strikes the Academy: Faculty Response Required
ERIC Educational Resources Information Center
DeBoy, James L.
2015-01-01
When the corporate storm strikes the academy, faculty must be willing and able to repel administrative assaults upon academic freedom, shared governance, and tenure. This paper will describe the on-going clash between administrators who embrace the corporate mindset and faculty who cherish traditions of shared governance and collegial…
Teacher Perceptions of Their Ethical Responsibility: The Balancing of Rights
ERIC Educational Resources Information Center
le Roux, Adré; Marais, Nalize
2013-01-01
Almost annually, South African education is troubled by strike action and the temporary discontinuation of teaching and learning. While teachers claim their constitutionally protected right to participate in strikes, learners' equally constitutionally protected right to education is violated. Not only is a tension between these two rights…
Working Women's Consciousness: Traditional or Oppositional?
ERIC Educational Resources Information Center
Costello, Cynthia
Based on an analysis of oral history interviews, this paper examines the events and consciousness surrounding a 1979 strike initiated by 53 female office employees of the Wisconsin Education Association (WEA) Insurance Trust. Faced with sex-discriminatory working conditions, the women at the Trust responded by initiating a strike. For many of the…
ERIC Educational Resources Information Center
Sharp, Malcolm
1973-01-01
Discusses the threat of a race for first-strike capacity as a factor influencing the achievement of world disarmament. Indicates that the process of graduated unilateral disarmament'' would be better than that of first-strike capacity by leaving enough time for one side to take comparable action after completion of disarmament efforts by the…
Remarkable Rates of Lightning Strike Mortality in Malawi
Borgerhoff Mulder, Monique; Msalu, Lameck; Caro, Tim; Salerno, Jonathan
2012-01-01
Livingstone's second mission site on the shore of Lake Malawi suffers very high rates of consequential lightning strikes. Comprehensive interviewing of victims and their relatives in seven Traditional Authorities in Nkhata Bay District, Malawi revealed that the annual rate of consequential strikes was 419/million, more than six times higher than that in other developing countries; the rate of deaths from lightning was 84/million/year, 5.4 times greater than the highest ever recorded. These remarkable figures reveal that lightning constitutes a significant stochastic source of mortality with potential life history consequences, but it should not deflect attention away from the more prominent causes of mortality in this rural area. PMID:22253708
Central hyperadrenergic state after lightning strike.
Parsaik, Ajay K; Ahlskog, J Eric; Singer, Wolfgang; Gelfman, Russell; Sheldon, Seth H; Seime, Richard J; Craft, Jennifer M; Staab, Jeffrey P; Kantor, Birgit; Low, Phillip A
2013-08-01
To describe and review autonomic complications of lightning strike. Case report and laboratory data including autonomic function tests in a subject who was struck by lightning. A 24-year-old man was struck by lightning. Following that, he developed dysautonomia, with persistent inappropriate sinus tachycardia and autonomic storms, as well as posttraumatic stress disorder (PTSD) and functional neurologic problems. The combination of persistent sinus tachycardia and episodic exacerbations associated with hypertension, diaphoresis, and agitation was highly suggestive of a central hyperadrenergic state with superimposed autonomic storms. Whether the additional PTSD and functional neurologic deficits were due to a direct effect of the lightning strike on the central nervous system or a secondary response is open to speculation.
Triggered lightning strikes to aircraft and natural intracloud discharges
NASA Technical Reports Server (NTRS)
Mazur, Vladislav
1989-01-01
The physical model of Mazur (1989) for triggering lightning strikes by aircraft was used to interpret the initiation of intracloud flashes observed by the French UHF-VHF interferometric system. It is shown that both the intracloud discharges and airplane-triggered lightning strikes were initiated by simultaneous bidirectional development of the negative stepped leader and the positive leader-continous current process. However, the negative stepped leader phase in triggered flashes is of shorter duration (tens of milliseconds), than that in intracloud flashes (usually hundreds of milliseconds). This is considered to be due to the fact that, on the aircraft there is a single initiation process, versus the numerous initiation processes that occur inside the cloud.
Central Hyperadrenergic State After Lightning Strike
Parsaik, Ajay K.; Ahlskog, J. Eric; Singer, Wolfgang; Gelfman, Russell; Sheldon, Seth H.; Seime, Richard J.; Craft, Jennifer M.; Staab, Jeffrey P.; Kantor, Birgit; Low, Phillip A.
2013-01-01
Objective To describe and review autonomic complications of lightning strike. Methods Case report and laboratory data including autonomic function tests in a subject who was struck by lightning. Results A 24-year-old man was struck by lightning. Following that, he developed dysautonomia, with persistent inappropriate sinus tachycardia and autonomic storms, as well as posttraumatic stress disorder (PTSD) and functional neurologic problems. Interpretation The combination of persistent sinus tachycardia and episodic exacerbations associated with hypertension, diaphoresis, and agitation were highly suggestive of a central hyperadrenergic state with superimposed autonomic storms. Whether the additional PTSD and functional neurologic deficits were due to a direct effect of the lightning strike on the CNS or a secondary response is open to speculation. PMID:23761114
A parabolic variational inequality arising from the valuation of strike reset options
NASA Astrophysics Data System (ADS)
Yang, Zhou; Yi, Fahuai; Dai, Min
A strike reset option is an option that allows its holder to reset the strike price to the prevailing underlying asset price at a moment chosen by the holder. The pricing model of the option can be formulated as a one-dimensional parabolic variational inequality, or equivalently, a free boundary problem, where the free boundary just corresponds to the optimal reset strategy adopted by the holder of the option. This paper is concerned with the theoretical analysis of the model. The existence and uniqueness of the solution are established. Furthermore, we study properties of the free boundary. The monotonicity and C smoothness of the free boundary are proven in some situations.
NASA Astrophysics Data System (ADS)
Zhang, Wei-Guo; Li, Zhe; Liu, Yong-Jun
2018-01-01
In this paper, we study the pricing problem of the continuously monitored fixed and floating strike geometric Asian power options in a mixed fractional Brownian motion environment. First, we derive both closed-form solutions and mixed fractional partial differential equations for fixed and floating strike geometric Asian power options based on delta-hedging strategy and partial differential equation method. Second, we present the lower and upper bounds of the prices of fixed and floating strike geometric Asian power options under the assumption that both risk-free interest rate and volatility are interval numbers. Finally, numerical studies are performed to illustrate the performance of our proposed pricing model.
Structured methods and striking moments: using question sequences in "living" ways.
Lowe, Roger
2005-03-01
This article draws together two seemingly incompatible practices in social constructionist therapies: the use of structured questioning methods (associated with solution-focused and narrative therapies) and the poetic elaboration of "striking moments" (associated with conversational therapies). To what extent can we value and use both styles of practice? Beginning with practitioners' concerns about the use of structured question sequences, I explore possibilities for resituating these methods in different conceptual and metaphorical frames, selectively drawing on ideas from the philosophy of striking moments. The aim is not to reduce one therapeutic style to another, but to encourage the teaching and practice of structured methods in more creative, improvisational, and "living" ways.
NASA Astrophysics Data System (ADS)
Pinet, Nicolas; Dietrich, Jim; Duchesne, Mathieu J.; Hinds, Steve J.; Brake, Virginia
2018-07-01
The Maritimes Basin is an upper Paleozoic sedimentary basin centered in the Gulf of St. Lawrence (Canada). Early phases of basin formation included the development of partly connected sub-basins bounded by high-angle faults, in an overall strike-slip setting. Interpretation of reprocessed seismic reflection data indicates that a low-angle detachment contributed to the formation of a highly asymmetric sub-basin. This detachment was rotated toward a lower angle and succeeded by high-angle faults that sole into the detachment or cut it. This model bears similarities to other highly extended terranes and appears to be applicable to strike-slip and/or transtensional settings.
Britain’s Nuclear Deterrent Force and the U.S.-U.K. Special Relationship
2014-06-01
a surprise first-strike. Protecting this dinosaur , by building hardened silos, was beyond the willingness and ability of the British government to...Streak took at least 20 minutes to fuel-up, it was always extremely vulnerable to a surprise first-strike. Protecting this dinosaur , by building hardened
Conventional Prompt Global Strike and Long-Range Ballistic Missiles: Background and Issues
2011-03-01
deployed. It also would be based on a conical design, with winglets , rather than on the winged design of the HTV-2. Upon nearing a target, the weapon...nuclear and conventional strike forces as a separate mission and separate concept from PGS, Congress, initially at least, blended both into the
75 FR 43097 - Airworthiness Directives; The Boeing Company Model 757 Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-23
... must be sealed for lightning strike protection. Relevant Service Information AD 2008-23-19 referred to... additional fasteners in the main fuel tanks must be sealed for lightning strike protection. The Federal... bundles inside the left and right equipment cooling system bays, on the left and right rear spars, and on...
ERIC Educational Resources Information Center
Goldman, Jill S.; Pfluge, Kevin F.
2010-01-01
Golf is a lifelong activity that people of all ages can enjoy if they experience success and have fun. Early involvement in the sport facilitates the development of the ability to strike an object with an implement. Striking with implements can be challenging for young children and teachers, but golf can be taught in all elementary school settings…
77 FR 46439 - Medicare Program; Prior Authorization for Power Mobility Device (PMD) Demonstration
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-03
... DOJ. Medicare Fraud Strike Force teams are a key component of HEAT, since their inception and based on... primary focus of investigation for these strike forces. The Comprehensive Error Rate Testing (CERT... various prior authorization scenarios: Scenario 1: When a submitter sends a prior authorization request to...
DOT National Transportation Integrated Search
1984-06-01
The August 1981 strike of air traffic control specialists (ATCS's) and their subsequent firing led to the air traffic strike recovery program, which included the unprecedented hiring and basic training of over 8,000 ATCS applicants in a 2-year period...
Conventional Prompt Global Strike and Long-Range Ballistic Missiles: Background and Issues
2016-02-24
13 The FALCON Study...range strike capabilities. These include bombers, cruise missiles, ballistic missiles, and boost-glide technologies that would mate a rocket booster...Command, Hearing, April 4, 2005. 23 Grossman, Elaine M., “U.S. General: Precise Long-Range Missiles may Enable Big Nuclear Cuts,” Inside the Pentagon
Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-21
... LLC Establishing Strike Price Intervals of $1 and Increasing Position and Exercise Limits With Respect... ``Index'') to (i) establish strike price intervals of $1.00 and (ii) increase the position and exercise... price intervals of $1.00 and (ii) increase the position and exercise limits applicable thereto. The...
USDA-ARS?s Scientific Manuscript database
Solanum morelliforme is an epiphytic wild potato (Solanum section Petota) species widely distributed throughout central Mexico to Honduras. A strikingly disjunct (4000 km) population was recently discovered in Bolivia, representing the first record of this species in South America. Our maximum entro...
Over-the-Line: An Alternative Striking/Fielding Game for Understanding
ERIC Educational Resources Information Center
Gorecki, Jennifer J.
2004-01-01
Over-the-Line is a striking/fielding game designed from the perspective of the Games for Understanding tactical model to serve as an alternative to traditional kickball, softball, and baseball. Over-the-Line can be modified for developmental appropriateness and tasks can increase in complexity as tactical awareness is attained. This article shares…
46 CFR 160.037-3 - Materials, workmanship, construction, and performance requirements.
Code of Federal Regulations, 2014 CFR
2014-10-01
... on its top with a friction striking material which shall, by a pull of the tear strip, be entirely exposed for striking the friction igniter button. The igniter button shall be non-water soluble or be... manner as to provide positive ignition by the friction striker. The igniter button shall be firmly...
46 CFR 160.037-3 - Materials, workmanship, construction, and performance requirements.
Code of Federal Regulations, 2011 CFR
2011-10-01
... on its top with a friction striking material which shall, by a pull of the tear strip, be entirely exposed for striking the friction igniter button. The igniter button shall be non-water soluble or be... manner as to provide positive ignition by the friction striker. The igniter button shall be firmly...
46 CFR 160.037-3 - Materials, workmanship, construction, and performance requirements.
Code of Federal Regulations, 2013 CFR
2013-10-01
... on its top with a friction striking material which shall, by a pull of the tear strip, be entirely exposed for striking the friction igniter button. The igniter button shall be non-water soluble or be... manner as to provide positive ignition by the friction striker. The igniter button shall be firmly...
46 CFR 160.037-3 - Materials, workmanship, construction, and performance requirements.
Code of Federal Regulations, 2012 CFR
2012-10-01
... on its top with a friction striking material which shall, by a pull of the tear strip, be entirely exposed for striking the friction igniter button. The igniter button shall be non-water soluble or be... manner as to provide positive ignition by the friction striker. The igniter button shall be firmly...
Mediation, Fact-finding, and Impasse.
ERIC Educational Resources Information Center
Dubel, Robert Y.
Since collective bargaining in public education is here to stay, boards of education should learn to accept it for what it is--an adversary process. The author contends that striking is not a very viable weapon in the arsenal of the teachers' union because the schools will continue to operate, and public pressure against prolonged strikes and…
Federal Register 2010, 2011, 2012, 2013, 2014
2010-10-26
... does not significantly affect the protection of investors or the public interest, does not impose any... this proposed rule change is to expand the $.50 Strike Program in order to provide investors with... proposal would expand $.50 strike offerings to market participants, such as traders and retail investors...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-01-20
... change does not significantly affect the protection of investors or the public interest, does not impose... provide investors and traders with additional opportunities and strategies to hedge high priced securities... believes the $5 Strike Price Program would offer investors a greater selection of strike prices at a lower...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-10-26
... does not significantly affect the protection of investors or the public interest, does not impose any... rule change is to expand the $.50 Strike Program in order to provide investors with opportunities and... proposal would expand $.50 strike offerings to market participants, such as traders and retail investors...
Lightning Strike Simula tion for Studying Southern Pine Bark and Engraver Beetle Attacks
Mitchel C. Miller
1983-01-01
Endemic populations of the southern pine beetle (Dendroctonus frontalis Zimm.) and Ips spp. attacked loblolly pines (Pinus taeda L.) on which lightning strikes were simulated with detonating cord in the field. Southern pine beetles were reared in successive generations in these trees from fall 1981 through spring 1982; only
76 FR 53364 - Recreational Vessel Propeller Strike and Carbon Monoxide Poisoning Casualty Prevention
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-26
... in Outdoor Recreation Activity Participation--1980 to Now, May 2009 (A Recreation Research Report in the Internet Research Information Series), available at http://warnell.forestry.uga.edu/nrrt/nsre... casualties caused by propeller strikes and carbon monoxide (CO) poisoning, we will hold a meeting at a time...
Eyeing New York's Newspaper Strike.
ERIC Educational Resources Information Center
Fishleder, Paul
The New York newspaper strike of 1978 was the direct result of a series of events that started in 1923 when the pressmen's union established a system that provided a minimum fixed number of pressmen per press unit and legitimized a loose labor pool. From that time, the number of pressmen increased through family-dominated union management that…
The Bellevue Teachers Strike and Its Implications for the Future of Postindustrial Reform Unionism
ERIC Educational Resources Information Center
Jacoby, Daniel F.; Nitta, Keith
2012-01-01
Striking for nine days in 2008, teachers in Bellevue carved a distinctive path through the contradictory movements for professional reform unionism and national accountability. In addition to compensation, Bellevue's teachers struck over the top-down prescriptive management epitomized by the Gates Foundation supported "Curriculum Web."…
USDA-ARS?s Scientific Manuscript database
BACKGROUND: Tall fescue containing a selected strain of the fungal endophyte Epichlöe coenophiala purported to express high levels of bioactive alkaloids (Avanex®) was recently commercialized for reducing airport bird strike hazard. We compared bioactivity of Avanex and KY 31, a ubiquitous cultivar...
Torts Liability for Strike Action and Third Party Rights.
ERIC Educational Resources Information Center
Raday, Frances
1979-01-01
Studies the nature of the torts liability incurred in strikes and the extent of existing immunities bestowed on strikers and their organizers, and explores the principles that should govern liability and immunity. Available from Israel Law Review Association, c/o Faculty of Law, Hebrew University of Jerusalem, Mount Scopus, P.O.B. 24100, Jerusalem…
Monte Carlo Simulation to Estimate Likelihood of Direct Lightning Strikes
NASA Technical Reports Server (NTRS)
Mata, Carlos; Medelius, Pedro
2008-01-01
A software tool has been designed to quantify the lightning exposure at launch sites of the stack at the pads under different configurations. In order to predict lightning strikes to generic structures, this model uses leaders whose origins (in the x-y plane) are obtained from a 2D random, normal distribution.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-05-26
... and ranking the arbitrators on the lists. Currently, parties are sent lists of available arbitrators...' ranking lists. However, after each side exercises its strikes, typically only one or two persons remain... additional arbitrators during the ranking and striking stage of the arbitrator appointment process. In...
The Student Strike at the National Autonomous University of Mexico: A Political Analysis.
ERIC Educational Resources Information Center
Rhoads, Robert A.; Mina, Liliana
2001-01-01
Analyzes political tensions related to student strikes at the Universidad Nacional Autonoma de Mexico (UNAM), 1998-2000, which were sparked by proposed tuition fees. Discusses conflict between social justice sentiments focused on free and egalitarian access to higher education versus market-driven views promoting selective, competitive higher…
Incorporating Two-Square into Physical Education
ERIC Educational Resources Information Center
Meyler, Tim; Wilson, Sandy
2012-01-01
Physical educators often struggle to teach individual striking skills to upper level (3-5 grade) elementary students. Finding a developmentally appropriate striking activity with a high participation rate can be a challenge. And sports such as tennis, pickleball, and badminton are often not an option for a variety of reasons (e.g., space or…
The Future of Drone Strikes: A Framework for Analyzing Policy Options
2014-09-01
Christmas Day” bomber, Umar Farouk Abdulmutallab, attempted to detonate a bomb hidden in his underwear during a flight to the U.S. in 2009. The...2013/08/the-case-against-drone-strikes-on-people- who-only-act-like-terrorists/278744/. 87 [30] Jack Goldsmith, “ Fire When Ready,” Foreign Policy
What To Do When Contagious Disease Strikes Your School.
ERIC Educational Resources Information Center
American Bar Association, Chicago, IL.
This publication presents 10 documents collected to accompany a seminar entitled "What To Do When Contagious Disease Strikes Your School," presented at the 31st annual convention of the National Organization on Legal Problems of Education in 1985. The materials include (1) an agenda of the seminar listing the speakers, their topics, and…
Impact Circuit Training in High School
ERIC Educational Resources Information Center
LaFleche, Marc Joseph
2012-01-01
This article discusses Impact Circuit Training (ICT) which combines dodging and striking movements to create a workout that increases physical fitness levels in participants. Participants of ICT will strike a heavy bag, mitts, and a speed bag, jump rope, throw and catch a medicine ball, and jog as part of their exercise program. No contact is made…
Lightning-Strike Disaster: Effects on Children's Fears and Worries.
ERIC Educational Resources Information Center
Dollinger, Stephen J.; And Others
1984-01-01
Compares fears of lightning-strike victims (N=29) with matched control children (N=58), using fear reports from children and their mothers. Differences between samples were most pronounced for child-reported fears. Correspondence between mothers' and children's reports of intense storm-related fears was markedly larger in the lightning sample than…
Impact Behaviour of Soft Body Projectiles
NASA Astrophysics Data System (ADS)
Kalam, Sayyad Abdul; Rayavarapu, Vijaya Kumar; Ginka, Ranga Janardhana
2018-02-01
Bird strike analysis is a common type of analysis done during the design and analysis of primary structures such as engine cowlings or fuselage panels. These simulations are done in order to predict whether various designs will pass the necessary certification tests. Composite materials are increasingly being used in aerospace industry and bird strike is a major threat which may lead to serious structural damage of those materials. Such phenomenon may arise from numerous impact scenarios. The focus of current study is on the finite element modeling for composite structures and simulation of high velocity impact loads from soft body projectiles with an explicit dynamics code AUTODYN. This paper investigates the methodology which can be utilized to certify an aircraft for bird strike resistance using computational technique by first demonstrating the accuracy of the method for bird impact on rigid target modeling and then applies the developed model to a more complex problem. The model developed for bird strike threat assessment incorporates parameters of bird number (bird density), bird body mass, equation of state (EOS) and bird path during impact.
Situational Lightning Climatologies
NASA Technical Reports Server (NTRS)
Bauman, William; Crawford, Winifred
2010-01-01
Research has revealed distinct spatial and temporal distributions of lightning occurrence that are strongly influenced by large-scale atmospheric flow regimes. It was believed there were two flow systems, but it has been discovered that actually there are seven distinct flow regimes. The Applied Meteorology Unit (AMU) has recalculated the lightning climatologies for the Shuttle Landing Facility (SLF), and the eight airfields in the National Weather Service in Melbourne (NWS MLB) County Warning Area (CWA) using individual lightning strike data to improve the accuracy of the climatologies. The software determines the location of each CG lightning strike with 5-, 10-, 20-, and 30-nmi (.9.3-, 18.5-, 37-, 55.6-km) radii from each airfield. Each CG lightning strike is binned at 1-, 3-, and 6-hour intervals at each specified radius. The software merges the CG lightning strike time intervals and distance with each wind flow regime and creates probability statistics for each time interval, radii, and flow regime, and stratifies them by month and warm season. The AMU also updated the graphical user interface (GUI) with the new data.
China, Victor; Levy, Liraz; Elmaliach, Tal
2017-01-01
Larval fishes experience extreme mortality rates, with 99% of a cohort perishing within days after starting to actively feed. While recent evidence suggests that hydrodynamic factors contribute to constraining larval feeding during early ontogeny, feeding is a complex process that involves numerous interacting behavioural and biomechanical components. How these components change throughout ontogeny and how they contribute to feeding remain unclear. Using 339 observations of larval feeding attempts, we quantified the effects of morphological and behavioural traits on feeding success of Sparus aurata larvae during early ontogeny. Feeding success was determined using high-speed videography, under both natural and increased water viscosity treatments. Successful strikes were characterized by Reynolds numbers that were an order of magnitude higher than those of failed strikes. The pattern of increasing strike success with increasing age was driven by the ontogeny of traits that facilitate the transition to higher Reynolds numbers. Hence, the physical growth of a larva plays an important role in its transition to a hydrodynamic regime of higher Reynolds numbers, in which suction feeding is more effective. PMID:28446697
Further identification and treatment modalities in telephone mediated lightning strike
NASA Technical Reports Server (NTRS)
Andrews, Christopher J.; Darveniza, Mat
1991-01-01
The results are presented of a prospective survey of people injured by lightning impulses transmitted by the public telephone system. The results are compared with those of a previous retrospective survey. Various deficiencies in the methodology of the latter survey are addressed. A division into a population with severe injury and a population with mild injury is made based on medical history and examination taken immediately after a strike. The best predictors of severe injury were found to be the presence of symptoms beyond one week after the strike, and also the initial presence of musculoskeletal injuries. Psychological upset is also seen to be a significant factor in severe injury. The only physical parameter of strike which could be used as a predictor of severe injury was the presence of concomitant power system damage. The importance of earth bonding between power and telephone system is thus supported in a protection strategy. One author draws on experience in treating patients with these injuries to propose a treatment regimen for those with ongoing symptoms. The importance of evaluating and treating psychological and physical aspects is stressed.
Oceanic broad multifault transform plate boundaries
NASA Astrophysics Data System (ADS)
Ligi, Marco; Bonatti, Enrico; Gasperini, Luca; Poliakov, Alexei N. B.
2002-01-01
Oceanic transform plate boundaries consist of a single, narrow (a few kilometers wide) strike-slip seismic zone offsetting two mid-ocean ridge segments. However, we define here a new class of oceanic transform boundaries, with broad complex multifault zones of deformation, similar to some continental strike-slip systems. Examples are the 750-km- long, 120-km-wide Andrew Bain transform on the Southwest Indian Ridge, and the Romanche transform, where the Mid-Atlantic Ridge is offset by a lens-shaped, ˜900-km- long, ˜100-km-wide sliver of deformed lithosphere bound by two major transform valleys. One of the valleys is seismically highly active and constitutes the present-day principal transform boundary. However, strike-slip seismic events also occur in the second valley and elsewhere in the deformed zone. Some of these events may be triggered by earthquakes from the principal boundary. Numerical modeling predicts the development of wide multiple transform boundaries when the age offset is above a threshold value of ˜30 m.y., i.e., in extra-long (>500 km) slow-slip transforms. Multiple boundaries develop so that strike-slip ruptures avoid very thick and strong lithosphere.
Dual Fragment Impact of PBX Charges
NASA Astrophysics Data System (ADS)
Haskins, Peter; Briggs, Richard; Leeming, David; White, Nathan; Cheese, Philip; DE&S MoD UK Team; Ordnance Test Solutions Ltd Team
2017-06-01
Fragment impact can pose a significant hazard to many systems containing explosives or propellants. Testing for this threat is most commonly carried out using a single fragment. However, it can be argued that an initial fragment strike (or strikes) could sensitise the energetic material to subsequent impacts, which may then lead to a more violent reaction than would have been predicted based upon single fragment studies. To explore this potential hazard we have developed the capability to launch 2 fragments from the same gun at a range of velocities, and achieve impacts on an acceptor charge with good control over the spatial and temporal separation of the strikes. In this paper we will describe in detail the experimental techniques we have used, both to achieve the dual fragment launch and observe the acceptor charge response. In addition, we will describe the results obtained against PBX filled explosive targets; discuss the mechanisms controlling the target response and their significance for vulnerability assessment. Results of these tests have clearly indicated the potential for detonation upon the second strike, at velocities well below those needed for shock initiation by a single fragment.
China, Victor; Levy, Liraz; Liberzon, Alex; Elmaliach, Tal; Holzman, Roi
2017-04-26
Larval fishes experience extreme mortality rates, with 99% of a cohort perishing within days after starting to actively feed. While recent evidence suggests that hydrodynamic factors contribute to constraining larval feeding during early ontogeny, feeding is a complex process that involves numerous interacting behavioural and biomechanical components. How these components change throughout ontogeny and how they contribute to feeding remain unclear. Using 339 observations of larval feeding attempts, we quantified the effects of morphological and behavioural traits on feeding success of Sparus aurata larvae during early ontogeny. Feeding success was determined using high-speed videography, under both natural and increased water viscosity treatments. Successful strikes were characterized by Reynolds numbers that were an order of magnitude higher than those of failed strikes. The pattern of increasing strike success with increasing age was driven by the ontogeny of traits that facilitate the transition to higher Reynolds numbers. Hence, the physical growth of a larva plays an important role in its transition to a hydrodynamic regime of higher Reynolds numbers, in which suction feeding is more effective. © 2017 The Author(s).
Continuum calculations of continental deformation in transcurrent environments
NASA Technical Reports Server (NTRS)
Sonder, L. J.; England, P. C.; Houseman, G. A.
1986-01-01
A thin viscous sheet approximation is used to investigate continental deformation near a strike-slip boundary. The vertically averaged velocity field is calculated for a medium characterized by a power law rheology with stress exponent n. Driving stresses include those applied along boundaries of the sheet and those arising from buoyancy forces related to lateral differences in crustal thickness. Exact and approximate analytic solutions for a region with a sinusoidal strike-slip boundary condition are compared with solutions for more geologically relevant boundary conditions obtained using a finite element technique. The across-strike length scale of the deformation is approximately 1/4pi x sq rt n times the dominant wavelength of the imposed strike-slip boundary condition for both the analytic and the numerical solutions; this result is consistent with length scales observed in continental regions of large-scale transcurrent faulting. An approximate, linear relationship between displacement and rotation is found that depends only on the deformation length scale and the rheology. Calculated displacements, finite rotations, and distribution of crustal thicknesses are consistent with those observed in the region of the Pacific-North America plate boundary in California.