Force-frequency and fatigue properties of motor units in muscles that control digits of the human hand.

PubMed

Fuglevand, A J; Macefield, V G; Bigland-Ritchie, B

1999-04-01

Modulation of motor unit activation rate is a fundamental process by which the mammalian nervous system encodes muscle force. To identify how rate coding of force may change as a consequence of fatigue, intraneural microstimulation of motor axons was used to elicit twitch and force-frequency responses before and after 2 min of intermittent stimulation (40-Hz train for 330 ms, 1 train/s) in single motor units of human long finger flexor muscles and intrinsic hand muscles. Before fatigue, two groups of units could be distinguished based on the stimulus frequency needed to elicit half-maximal force; group 1 (n = 8) required 9.1 +/- 0.5 Hz (means +/- SD), and group 2 (n = 5) required 15.5 +/- 1.1 Hz. Twitch contraction times were significantly different between these two groups (group 1 = 66. 5 ms; group 2 = 45.9 ms). Overall 18% of the units were fatigue resistant [fatigue index (FI) > 0.75], 64% had intermediate fatigue sensitivity (0.25

Hierarchical control of motor units in voluntary contractions

PubMed Central

Contessa, Paola

2012-01-01

For the past five decades there has been wide acceptance of a relationship between the firing rate of motor units and the afterhyperpolarization of motoneurons. It has been promulgated that the higher-threshold, larger-soma, motoneurons fire faster than the lower-threshold, smaller-soma, motor units. This relationship was based on studies on anesthetized cats with electrically stimulated motoneurons. We questioned its applicability to motor unit control during voluntary contractions in humans. We found that during linearly force-increasing contractions, firing rates increased as exponential functions. At any time and force level, including at recruitment, the firing rate values were inversely related to the recruitment threshold of the motor unit. The time constants of the exponential functions were directly related to the recruitment threshold. From the Henneman size principle it follows that the characteristics of the firing rates are also related to the size of the soma. The “firing rate spectrum” presents a beautifully simple control scheme in which, at any given time or force, the firing rate value of earlier-recruited motor units is greater than that of later-recruited motor units. This hierarchical control scheme describes a mechanism that provides an effective economy of force generation for the earlier-recruited lower force-twitch motor units, and reduces the fatigue of later-recruited higher force-twitch motor units—both characteristics being well suited for generating and sustaining force during the fight-or-flight response. PMID:21975447

An Evaluation of Northern Hemisphere Merged Cloud Analyses from the United States Air Force Cloud Depiction Forecasting System II

DTIC Science & Technology

2013-03-01

layering and typing to provide a vertical stratification of the cloud-filled pixels detected in Level 2. Level 3 output is remapped to the standard AFWA...analyses are compared to one another to see if the most recent analysis also has the lowest estimated error. Optimum interpolation (OI) occurs when...NORTHERN HEMISPHERE MERGED CLOUD ANALYSES FROM THE UNITED STATES AIR FORCE CLOUD DEPICTION FORECASTING SYSTEM II by Chandra M. Pasillas March

An Improved Maintenance Model for the Simulation of Strategic Airlift Capability.

DTIC Science & Technology

1982-03-01

developed using SLAM as the primary simulation language. Maintenance manning is modeled at the Air Force Specialty Code level, to allow the possibility of...Atlantic Treaty Organization (NATO) allies is one of our primary national objectives, but recent increases in Soviet ground and air forces (Ref 5:100) have...arrive from the United States. Consequently, the primary objective of the United States Air Force mobility program is to be able, by 1982, to double the

SIMNET CVCC SIMNWT Simulation of Radio Communication: A Testbed for Investigation of C3I Technology

DTIC Science & Technology

1991-07-01

level units to fight force-on-force engagements against an opposing unit of similar composition . Furthermore, it does so in the context of a joint...inexpensive to implement, this system has several important limitations as a simulation of Army VHP radios: • aiu/ radio can communicate with any

The compensatory interaction between motor unit firing behavior and muscle force during fatigue

PubMed Central

De Luca, Carlo J.; Kline, Joshua C.

2016-01-01

Throughout the literature, different observations of motor unit firing behavior during muscle fatigue have been reported and explained with varieties of conjectures. The disagreement amongst previous studies has resulted, in part, from the limited number of available motor units and from the misleading practice of grouping motor unit data across different subjects, contractions, and force levels. To establish a more clear understanding of motor unit control during fatigue, we investigated the firing behavior of motor units from the vastus lateralis muscle of individual subjects during a fatigue protocol of repeated voluntary constant force isometric contractions. Surface electromyographic decomposition technology provided the firings of 1,890 motor unit firing trains. These data revealed that to sustain the contraction force as the muscle fatigued, the following occurred: 1) motor unit firing rates increased; 2) new motor units were recruited; and 3) motor unit recruitment thresholds decreased. Although the degree of these adaptations was subject specific, the behavior was consistent in all subjects. When we compared our empirical observations with those obtained from simulation, we found that the fatigue-induced changes in motor unit firing behavior can be explained by increasing excitation to the motoneuron pool that compensates for the fatigue-induced decrease in muscle force twitch reported in empirical studies. Yet, the fundamental motor unit control scheme remains invariant throughout the development of fatigue. These findings indicate that the central nervous system regulates motor unit firing behavior by adjusting the operating point of the excitation to the motoneuron pool to sustain the contraction force as the muscle fatigues. PMID:27385798

The compensatory interaction between motor unit firing behavior and muscle force during fatigue.

PubMed

Contessa, Paola; De Luca, Carlo J; Kline, Joshua C

2016-10-01

Throughout the literature, different observations of motor unit firing behavior during muscle fatigue have been reported and explained with varieties of conjectures. The disagreement amongst previous studies has resulted, in part, from the limited number of available motor units and from the misleading practice of grouping motor unit data across different subjects, contractions, and force levels. To establish a more clear understanding of motor unit control during fatigue, we investigated the firing behavior of motor units from the vastus lateralis muscle of individual subjects during a fatigue protocol of repeated voluntary constant force isometric contractions. Surface electromyographic decomposition technology provided the firings of 1,890 motor unit firing trains. These data revealed that to sustain the contraction force as the muscle fatigued, the following occurred: 1) motor unit firing rates increased; 2) new motor units were recruited; and 3) motor unit recruitment thresholds decreased. Although the degree of these adaptations was subject specific, the behavior was consistent in all subjects. When we compared our empirical observations with those obtained from simulation, we found that the fatigue-induced changes in motor unit firing behavior can be explained by increasing excitation to the motoneuron pool that compensates for the fatigue-induced decrease in muscle force twitch reported in empirical studies. Yet, the fundamental motor unit control scheme remains invariant throughout the development of fatigue. These findings indicate that the central nervous system regulates motor unit firing behavior by adjusting the operating point of the excitation to the motoneuron pool to sustain the contraction force as the muscle fatigues. Copyright © 2016 the American Physiological Society.

Changes in motor unit recruitment strategy during pain alters force direction.

PubMed

Tucker, Kylie J; Hodges, Paul W

2010-10-01

Motor unit (MU) recruitment is altered (decreased discharge rate and cessation of discharge in some units, and recruitment of new units) in force-matched contractions during pain compared to contractions performed before pain. As MU's within a motoneurone pool have different force direction properties we hypothesised that altered MU recruitment during experimental knee pain would change the force vector (total force (F(T)): amplitude and angle) generated by the quadriceps. Force was produced at two levels during 1 × 60-s and 3 × 10-s isometric contractions of knee extensors, and recorded by two force transducers at right angles. This enabled calculation of both F(E) (extension force) and F(T). MU recruitment was recorded from the medial and lateral vastii with four fine-wire electrodes. Pain was induced by hypertonic saline injection in the infra-patella fat pad. Nine subjects matched F(E) and six subjects also matched both medial and lateral forces (F(T)) before and during pain. Changes in MU discharge pattern (decreased discharge rate (P<0.001), complete cessation of firing, and recruitment of new units) during pain were associated with a ∼5° change in absolute force angle. As force angle changed in both directions (left/right) for individual subjects with pain there was no change in average F(T) amplitude between conditions. When both medial and lateral forces were matched MU discharge rate decreased (P<0.001) with pain, but, fewer units ceased firing or were newly recruited during pain. Change in motoneurone recruitment during pain alters direction of muscle force. This may be a strategy to avoid pain or protect the painful part. Copyright © 2010 European Federation of International Association for the Study of Pain Chapters. Published by Elsevier Ltd. All rights reserved.

Unique risk and protective factors for partner aggression in a large scale air force survey.

PubMed

Slep, Amy M Smith; Foran, Heather M; Heyman, Richard E; Snarr, Jeffery D

2010-08-01

The objective of this study is to examine risk factors of physical aggression against a partner in a large representative Active Duty Air Force sample. A stratified sample of 128,950 United States Active Duty members were invited to participate in an Air Force-wide anonymous online survey across 82 bases. The final sample (N = 52,780) was weighted to be representative of the United States Air Force. Backward stepwise regression analyses were conducted to identify unique predictors of partner physical aggression perpetration within and across different ecological levels (individual, family, organization, and community levels). Relationship satisfaction, alcohol problems, financial stress, and number of years in the military were identified as unique predictors of men's and women's perpetration of violence against their partner across ecological levels. Parental status, support from neighbors, personal coping, and support from formal agencies also uniquely predicted men's but not women's perpetration of violence across ecological levels. This study identified specific risk factors of partner violence that may be targeted by prevention and intervention efforts aimed at different levels of impact (e.g., family interventions, community-wide programs).

Sources of signal-dependent noise during isometric force production.

PubMed

Jones, Kelvin E; Hamilton, Antonia F; Wolpert, Daniel M

2002-09-01

It has been proposed that the invariant kinematics observed during goal-directed movements result from reducing the consequences of signal-dependent noise (SDN) on motor output. The purpose of this study was to investigate the presence of SDN during isometric force production and determine how central and peripheral components contribute to this feature of motor control. Peripheral and central components were distinguished experimentally by comparing voluntary contractions to those elicited by electrical stimulation of the extensor pollicis longus muscle. To determine other factors of motor-unit physiology that may contribute to SDN, a model was constructed and its output compared with the empirical data. SDN was evident in voluntary isometric contractions as a linear scaling of force variability (SD) with respect to the mean force level. However, during electrically stimulated contractions to the same force levels, the variability remained constant over the same range of mean forces. When the subjects were asked to combine voluntary with stimulation-induced contractions, the linear scaling relationship between the SD and mean force returned. The modeling results highlight that much of the basic physiological organization of the motor-unit pool, such as range of twitch amplitudes and range of recruitment thresholds, biases force output to exhibit linearly scaled SDN. This is in contrast to the square root scaling of variability with mean force present in any individual motor-unit of the pool. Orderly recruitment by twitch amplitude was a necessary condition for producing linearly scaled SDN. Surprisingly, the scaling of SDN was independent of the variability of motoneuron firing and therefore by inference, independent of presynaptic noise in the motor command. We conclude that the linear scaling of SDN during voluntary isometric contractions is a natural by-product of the organization of the motor-unit pool that does not depend on signal-dependent noise in the motor command. Synaptic noise in the motor command and common drive, which give rise to the variability and synchronization of motoneuron spiking, determine the magnitude of the force variability at a given level of mean force output.

77 FR 66595 - U.S. Air Force Broadcast of Consent Order, and Determination of Interest Level for a United...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-06

...: Headquarters Air Force, Deputy Under Secretary of the Air Force (Space). ACTION: Publicize Consent Order, and... solicitation issuance. The Deputy Under Secretary of the Air Force (Space), as the Compliance Officer under the...) ULA afford all space vehicle manufacturers [[Page 66596

Command and Control Warfare. Putting Another Tool in the War-Fighter’s Data Base

DTIC Science & Technology

1994-09-01

information dominance , friendly commanders will be able to work inside the enemy commander’s decision-making cycle forcing him to be reactive and thus cede the initiative and advantage to friendly forces. In any conflict, from large scale transregional to small scale, localized counter-insurgency, a joint or coalition team drawn together from the capabilities of each service and orchestrated by the joint force or theater- level commander will execute the responses of the United States armed forces. Units should perform their specific roles in accordance with the

Fiber networks amplify active stress

NASA Astrophysics Data System (ADS)

Lenz, Martin; Ronceray, Pierre; Broedersz, Chase

Large-scale force generation is essential for biological functions such as cell motility, embryonic development, and muscle contraction. In these processes, forces generated at the molecular level by motor proteins are transmitted by disordered fiber networks, resulting in large-scale active stresses. While fiber networks are well characterized macroscopically, this stress generation by microscopic active units is not well understood. I will present a comprehensive theoretical study of force transmission in these networks. I will show that the linear, small-force response of the networks is remarkably simple, as the macroscopic active stress depends only on the geometry of the force-exerting unit. In contrast, as non-linear buckling occurs around these units, local active forces are rectified towards isotropic contraction and strongly amplified. This stress amplification is reinforced by the networks' disordered nature, but saturates for high densities of active units. I will show that our predictions are quantitatively consistent with experiments on reconstituted tissues and actomyosin networks, and that they shed light on the role of the network microstructure in shaping active stresses in cells and tissue.

Estimating contraction level using root mean square amplitude in control subjects and patients with neuromuscular disorders.

PubMed

Boe, Shaun G; Rice, Charles L; Doherty, Timothy J

2008-04-01

To assess the utility of the surface electromyographic signal as a means of estimating the level of muscle force during quantitative electromyography studies by examining the relationship between muscle force and the amplitude of the surface electromyographic activity signal; and to determine the impact of a reduction in the number of motor units on this relationship, through inclusion of a sample of patients with neuromuscular disease. Cross-sectional, cohort study design. Tertiary care, ambulatory, electromyography laboratory. A volunteer, convenience sample of healthy control subjects (n=10), patients with amyotrophic lateral sclerosis (n=9), and patients with Charcot-Marie-Tooth disease type X (n=5). Not applicable. The first dorsal interosseous (FDI) and biceps brachii muscles were examined. Force values (at 10% increments) were calculated from two 4-second maximal voluntary contractions (MVCs). Surface electromyographic activity was recorded during separate 4-second voluntary contractions at 9 force increments (10% -90% of MVC). Additionally, a motor unit number estimate was derived for each subject to quantify the degree of motor unit loss in patients relative to control subjects. The relationships between force and surface electromyographic activity for both muscles (controls and patients) were best fit by a linear function. The variability about the grouped regression lines was quantified by 95% confidence intervals and found to be +/-6.7% (controls) and +/-8.5% (patients) for the FDI and +/-5% (controls) and +/-6.1% (patients) for the biceps brachii. These results suggest that the amplitude of the surface electromyographic activity signal may be used as a means of estimating the level of muscle force during quantitative electromyography studies. Future studies should be directed at examining if the variability associated with these force and surface electromyographic activity relationships is acceptable in replacing previous methods of measuring muscle force.

Motor Unit Interpulse Intervals During High Force Contractions.

PubMed

Stock, Matt S; Thompson, Brennan J

2016-01-01

We examined the means, medians, and variability for motor-unit interpulse intervals (IPIs) during voluntary, high force contractions. Eight men (mean age = 22 years) attempted to perform isometric contractions at 90% of their maximal voluntary contraction force while bipolar surface electromyographic (EMG) signals were detected from the vastus lateralis and vastus medialis muscles. Surface EMG signal decomposition was used to determine the recruitment thresholds and IPIs of motor units that demonstrated accuracy levels ≥ 96.0%. Motor units with high recruitment thresholds demonstrated longer mean IPIs, but the coefficients of variation were similar across all recruitment thresholds. Polynomial regression analyses indicated that for both muscles, the relationship between the means and standard deviations of the IPIs was linear. The majority of IPI histograms were positively skewed. Although low-threshold motor units were associated with shorter IPIs, the variability among motor units with differing recruitment thresholds was comparable.

Human spinal cord injury: motor unit properties and behaviour.

PubMed

Thomas, C K; Bakels, R; Klein, C S; Zijdewind, I

2014-01-01

Spinal cord injury (SCI) results in widespread variation in muscle function. Review of motor unit data shows that changes in the amount and balance of excitatory and inhibitory inputs after SCI alter management of motoneurons. Not only are units recruited up to higher than usual relative forces when SCI leaves few units under voluntary control, the force contribution from recruitment increases due to elevation of twitch/tetanic force ratios. Force gradation and precision are also coarser with reduced unit numbers. Maximal unit firing rates are low in hand muscles, limiting voluntary strength, but are low, normal or high in limb muscles. Unit firing rates during spasms can exceed voluntary rates, emphasizing that deficits in descending drive limit force production. SCI also changes muscle properties. Motor unit weakness and fatigability seem universal across muscles and species, increasing the muscle weakness that arises from paralysis of units, motoneuron death and sensory impairment. Motor axon conduction velocity decreases after human SCI. Muscle contractile speed is also reduced, which lowers the stimulation frequencies needed to grade force when paralysed muscles are activated with patterned electrical stimulation. This slowing does not necessarily occur in hind limb muscles after cord transection in cats and rats. The nature, duration and level of SCI underlie some of these species differences, as do variations in muscle function, daily usage, tract control and fibre-type composition. Exploring this diversity is important to promote recovery of the hand, bowel, bladder and locomotor function most wanted by people with SCI. © 2013 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.

Updating the Inductee Delivery Schedule.

DTIC Science & Technology

1987-03-01

deployed forces at risk with the anticipated opposing forces for the expected level of combat intensity. An estimate of the number of individuals who...identification of shortfalls in critical skills. It prescribes the anticipation of requirements and return of personnel resources to military control as...with the Time Phased Force Deployment Data lists the forces that will be deployed over time. Each unit is then assigned to a risk group (forces

Geohydrologic units and water-level conditions in the Terrace alluvial aquifer and Paluxy Aquifer, May 1993 and February 1994, near Air Force Plant 4, Fort Worth area, Texas

USGS Publications Warehouse

Rivers, Glen A.; Baker, Ernest T.; Coplin, L.S.

1996-01-01

The terrace alluvial aquifer underlying Air Force Plant 4 and the adjacent Naval Air Station (formerly Carswell Air Force Base) in the Fort Worth area, Texas, is contaminated locally with organic and metal compounds. Residents south and west of Air Force Plant 4 and the Naval Air Station are concerned that contaminants might enter the underlying Paluxy aquifer, which provides water to the city of White Settlement, south of Air Force Plant 4, and to residents west of Air Force Plant 4. The U.S. Environmental Protection Agency has qualified Air Force Plant 4 for Superfund cleanup. The pertinent geologic units include -A~rom oldest to youngest the Glen Rose, Paluxy, and Walnut Formations, Goodland Limestone, and terrace alluvial deposits. Except for the Glen Rose Formation, all units crop out at or near Air Force Plant 4 and the Naval Air Station. The terrace alluvial deposits, which nearly everywhere form the land surface, range from 0 to about 60 feet thick. These deposits comprise a mostly unconsolidated mixture of gravel, sand, silt, and clay. Mudstone and sandstone of the Paluxy Formation crop out north, west, and southwest of Lake Worth and total between about 130 and about 175 feet thick. The terrace alluvial deposits and the Paluxy Formation comprise the terrace alluvial aquifer and the Paluxy aquifer, respectively. These aquifers are separated by the Goodland-Walnut confining unit, composed of the Goodland Limestone and (or) Walnut Formation. Below the Paluxy aquifer, the Glen Rose Formation forms the Glen Rose confining unit. Water-level measurements during May 1993 and February 1994 from wells in the terrace alluvial aquifer indicate that, regionally, ground water flows toward the east-southeast beneath Air Force Plant 4 and the Naval Air Station. Locally, water appears to flow outward from ground-water mounds maintained by the localized infiltration of precipitation and reportedly by leaking water pipes and sanitary and (or) storm sewer lines beneath the assembly building at Air Force Plant 4. North of Farmers Branch, the terrace alluvial aquifer discharges into Lake Worth, Meandering Road Creek, Farmers Branch, and the West Fork Trinity River. South of Farmers Branch, ground water appears to flow mostly north-northeastward. Greater precipitation prior to the May 1993 measurements caused water levels to average approximately 5 ft higher in May 1993 than in February 1994. Regional ground-water gradients indicate west to east-southeastward flow in the Paluxy aquifer, with a dominant southeastward component beneath Air Force Plant 4. Water-level maps for the Paluxy "upper sand" reveal an elongated groundwater mound beneath southeastern parts of Air Force Plant 4, which indicates a localized, vertical conduit through which contaminated water from the terrace alluvial aquifer might enter upper parts of the Paluxy aquifer. The Paluxy "upper sand" apparently is mostly unsaturated and hydraulically separated from the deeper, regionally extensive parts of the Paluxy aquifer, most of which are fully saturated. While water levels in the "upper sand" were as much as 10 ft higher in May 1993 than in February 1994, water levels in most deeper parts of the Paluxy aquifer were slightly higher in February 1994 than they were in May 1993.

Enabling Early Sustainment Decisions: Application to F-35 Depot-Level Maintenance

DTIC Science & Technology

2013-01-01

Level Maintenance John G. Drew, Ronald G. McGarvey, Peter Buryk Research Report Enabling Early Sustainment Decisions Application to F-35 Depot-Level...Maintenance John G. Drew, Ronald G. McGarvey, Peter Buryk RAND Project AIR FORCE Prepared for the United States Air Force Approved for public...Related publications include the following: John Drew, Russell D. Shaver, Kristin F. Lynch, Mahyar A. Amouzegar, and Don Snyder, Unmanned Aerial

Size principle and information theory.

PubMed

Senn, W; Wyler, K; Clamann, H P; Kleinle, J; Lüscher, H R; Müller, L

1997-01-01

The motor units of a skeletal muscle may be recruited according to different strategies. From all possible recruitment strategies nature selected the simplest one: in most actions of vertebrate skeletal muscles the recruitment of its motor units is by increasing size. This so-called size principle permits a high precision in muscle force generation since small muscle forces are produced exclusively by small motor units. Larger motor units are activated only if the total muscle force has already reached certain critical levels. We show that this recruitment by size is not only optimal in precision but also optimal in an information theoretical sense. We consider the motoneuron pool as an encoder generating a parallel binary code from a common input to that pool. The generated motoneuron code is sent down through the motoneuron axons to the muscle. We establish that an optimization of this motoneuron code with respect to its information content is equivalent to the recruitment of motor units by size. Moreover, maximal information content of the motoneuron code is equivalent to a minimal expected error in muscle force generation.

Understanding Attitudes on Gender and Training at the United States Air Force Academy

DTIC Science & Technology

2005-01-01

hypotheses ................................................. 44 3. Correlations among sexism scales and impact of women on the physical fitness standards...fitness standards. Specifically, levels of sexism regarding women in society, the roles of women in combat, women and certain military jobs, and the ...at the United States Air Force Academy. Items 1 to 8 are the Modem Sexism Scale (MSS) developed by Swim, Aikin, Hall, and Hunter (1995), items 9-12

32 CFR 855.1 - Policy.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 6 2010-07-01 2010-07-01 false Policy. 855.1 Section 855.1 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE AIRCRAFT CIVIL AIRCRAFT USE OF UNITED STATES AIR FORCE AIRFIELDS General Provisions § 855.1 Policy. The Air Force establishes and uses its airfields to support the scope and level of...

Variations in Static Force Control and Motor Unit Behavior with Error Amplification Feedback in the Elderly.

PubMed

Chen, Yi-Ching; Lin, Linda L; Lin, Yen-Ting; Hu, Chia-Ling; Hwang, Ing-Shiou

2017-01-01

Error amplification (EA) feedback is a promising approach to advance visuomotor skill. As error detection and visuomotor processing at short time scales decline with age, this study examined whether older adults could benefit from EA feedback that included higher-frequency information to guide a force-tracking task. Fourteen young and 14 older adults performed low-level static isometric force-tracking with visual guidance of typical visual feedback and EA feedback containing augmented high-frequency errors. Stabilogram diffusion analysis was used to characterize force fluctuation dynamics. Also, the discharge behaviors of motor units and pooled motor unit coherence were assessed following the decomposition of multi-channel surface electromyography (EMG). EA produced different behavioral and neurophysiological impacts on young and older adults. Older adults exhibited inferior task accuracy with EA feedback than with typical visual feedback, but not young adults. Although stabilogram diffusion analysis revealed that EA led to a significant decrease in critical time points for both groups, EA potentiated the critical point of force fluctuations [Formula: see text], short-term effective diffusion coefficients (Ds), and short-term exponent scaling only for the older adults. Moreover, in older adults, EA added to the size of discharge variability of motor units and discharge regularity of cumulative discharge rate, but suppressed the pooled motor unit coherence in the 13-35 Hz band. Virtual EA alters the strategic balance between open-loop and closed-loop controls for force-tracking. Contrary to expectations, the prevailing use of closed-loop control with EA that contained high-frequency error information enhanced the motor unit discharge variability and undermined the force steadiness in the older group, concerning declines in physiological complexity in the neurobehavioral system and the common drive to the motoneuronal pool against force destabilization.

Variations in Static Force Control and Motor Unit Behavior with Error Amplification Feedback in the Elderly

PubMed Central

Chen, Yi-Ching; Lin, Linda L.; Lin, Yen-Ting; Hu, Chia-Ling; Hwang, Ing-Shiou

2017-01-01

Error amplification (EA) feedback is a promising approach to advance visuomotor skill. As error detection and visuomotor processing at short time scales decline with age, this study examined whether older adults could benefit from EA feedback that included higher-frequency information to guide a force-tracking task. Fourteen young and 14 older adults performed low-level static isometric force-tracking with visual guidance of typical visual feedback and EA feedback containing augmented high-frequency errors. Stabilogram diffusion analysis was used to characterize force fluctuation dynamics. Also, the discharge behaviors of motor units and pooled motor unit coherence were assessed following the decomposition of multi-channel surface electromyography (EMG). EA produced different behavioral and neurophysiological impacts on young and older adults. Older adults exhibited inferior task accuracy with EA feedback than with typical visual feedback, but not young adults. Although stabilogram diffusion analysis revealed that EA led to a significant decrease in critical time points for both groups, EA potentiated the critical point of force fluctuations <ΔFc2>, short-term effective diffusion coefficients (Ds), and short-term exponent scaling only for the older adults. Moreover, in older adults, EA added to the size of discharge variability of motor units and discharge regularity of cumulative discharge rate, but suppressed the pooled motor unit coherence in the 13–35 Hz band. Virtual EA alters the strategic balance between open-loop and closed-loop controls for force-tracking. Contrary to expectations, the prevailing use of closed-loop control with EA that contained high-frequency error information enhanced the motor unit discharge variability and undermined the force steadiness in the older group, concerning declines in physiological complexity in the neurobehavioral system and the common drive to the motoneuronal pool against force destabilization. PMID:29167637

The Total Force: Cultural Considerations for the Future of the Total Force Integration

DTIC Science & Technology

2017-03-31

force. In order to achieve a new TFI culture the Air Force must make a plan, and provide the education , tools, and road map; to cultivate a new set of...Force leadership; and taught holistically at all levels, ranks; and in every professional military education institution. 3 Part I...complex than transferring assets and improving individual units. Cohen’s principles spoke to a need for a cultural transformation . Today’s TFI concept

Alongshore wind forcing of coastal sea level as a function of frequency

USGS Publications Warehouse

Ryan, H.F.; Noble, M.A.

2006-01-01

The amplitude of the frequency response function between coastal alongshore wind stress and adjusted sea level anomalies along the west coast of the United States increases linearly as a function of the logarithm (log10) of the period for time scales up to at least 60, and possibly 100, days. The amplitude of the frequency response function increases even more rapidly at longer periods out to at least 5 yr. At the shortest periods, the amplitude of the frequency response function is small because sea level is forced only by the local component of the wind field. The regional wind field, which controls the wind-forced response in sea level for periods between 20 and 100 days, not only has much broader spatial scales than the local wind, but also propagates along the coast in the same direction as continental shelf waves. Hence, it has a stronger coupling to and an increased frequency response for sea level. At periods of a year or more, observed coastal sea level fluctuations are not only forced by the regional winds, but also by joint correlations among the larger-scale climatic patterns associated with El Nin??o. Therefore, the amplitude of the frequency response function is large, despite the fact that the energy in the coastal wind field is relatively small. These data show that the coastal sea level response to wind stress forcing along the west coast of the United States changes in a consistent and predictable pattern over a very broad range of frequencies with time scales from a few days to several years.

The effect of aircraft control forces on pilot performance during instrument landings in a flight simulator.

PubMed

Hewson, D J; McNair, P J; Marshall, R N

2001-07-01

Pilots may have difficulty controlling aircraft at both high and low force levels due to larger variability in force production at these force levels. The aim of this study was to measure the force variability and landing performance of pilots during an instrument landing in a flight simulator. There were 12 pilots who were tested while performing 5 instrument landings in a flight simulator, each of which required different control force inputs. Pilots can produce the least force when pushing the control column to the right, therefore the force levels for the landings were set relative to each pilot's maximum aileron-right force. The force levels for the landings were 90%, 60%, and 30% of maximal aileron-right force, normal force, and 25% of normal force. Variables recorded included electromyographic activity (EMG), aircraft control forces, aircraft attitude, perceived exertion and deviation from glide slope and heading. Multivariate analysis of variance was used to test for differences between landings. Pilots were least accurate in landing performance during the landing at 90% of maximal force (p < 0.05). There was also a trend toward decreased landing performance during the landing at 25% of normal force. Pilots were more variable in force production during the landings at 60% and 90% of maximal force (p < 0.05). Pilots are less accurate at performing instrument landings when control forces are high due to the increased variability of force production. The increase in variability at high force levels is most likely associated with motor unit recruitment, rather than rate coding. Aircraft designers need to consider the reduction in pilot performance at high force levels, as well as pilot strength limits when specifying new standards.

Serum Penicillin G Levels Are Lower Than Expected in Adults within Two Weeks of Administration of 1.2 Million Units

DTIC Science & Technology

2011-10-01

United States of America, 3 United States Department of Defense Global Emerging Infections Surveillance and Response System, Silver Spring, Maryland... infections . Citation: Broderick MP, Hansen CJ, Russell KL, Kaplan EL, Blumer JL, et al. (2011) Serum Penicillin G Levels Are Lower Than Expected in...Defense Global Emerging Infections Surveillance and Response System, a Division of the Armed Forces Health Surveillance Center, WU# 60501, http://afhsc.mil

High Frontier: The Journal for Space & Missile Professionals. Volume 2, Number 4, August 2006

DTIC Science & Technology

2006-08-01

among nations. With the information revolution, globalization has sped economic disparity and rapid cultural changes that have forced the United States...at every level to react to any Chinese move that puts targets from economic targets to military forces at risk of at- tack.12 The United States...Support Program (DSP) has been a model of war-fight- ing effectiveness for decades and exceeded all expectations, but its life span is not infinite. As

Large motor units are selectively affected following a stroke.

PubMed

Lukács, M; Vécsei, L; Beniczky, S

2008-11-01

Previous studies have revealed a loss of functioning motor units in stroke patients. However, it remained unclear whether the motor units are affected randomly or in some specific pattern. We assessed whether there is a selective loss of the large (high recruitment threshold) or the small (low recruitment threshold) motor units following a stroke. Forty-five stroke patients and 40 healthy controls participated in the study. Macro-EMG was recorded from the abductor digiti minimi muscle at two levels of force output (low and high). The median macro motor unit potential (macro-MUP) amplitude on the paretic side was compared with those on the unaffected side and in the controls. In the control group and on the unaffected side, the macro-MUPs were significantly larger at the high force output than at the low one. However, on the paretic side the macro-MUPs at the high force output had the same amplitude as those recorded at the low force output. These changes correlated with the severity of the paresis. Following a stroke, there is a selective functional loss of the large, high-threshold motor units. These changes are related to the severity of the symptoms. Our findings furnish further insight into the pathophysiology of the motor deficit following a stroke.

Influence of proprioceptive feedback on the firing rate and recruitment of motoneurons

NASA Astrophysics Data System (ADS)

De Luca, C. J.; Kline, J. C.

2012-02-01

We investigated the relationships of the firing rate and maximal recruitment threshold of motoneurons recorded during isometric contraction with the number of spindles in individual muscles. At force levels above 10% of maximal voluntary contraction, the firing rate was inversely related to the number of spindles in a muscle, with the slope of the relationship increasing with force. The maximal recruitment threshold of motor units increased linearly with the number of spindles in the muscle. Thus, muscles with a greater number of spindles had lower firing rates and a greater maximal recruitment threshold. These findings may be explained by a mechanical interaction between muscle fibres and adjacent spindles. During low-level (0% to 10%) voluntary contractions, muscle fibres of recruited motor units produce force twitches that activate nearby spindles to respond with an immediate excitatory feedback that reaches maximal level. As the force increases further, the twitches overlap and tend towards tetanization, the muscle fibres shorten, the spindles slacken, their excitatory firings decrease, and the net excitation to the homonymous motoneurons decreases. Motoneurons of muscles with greater number of spindles receive a greater decrease in excitation which reduces their firing rates, increases their maximal recruitment threshold, and changes the motoneuron recruitment distribution.

Discharge behavior of motor units in knee extensors during the initial stage of constant-force isometric contraction at low force level.

PubMed

Kamo, Mifuyu

2002-03-01

To elucidate the strategy of the activity of motor units (MUs) to maintain a constant-force isometric contraction, I examined the behavior of MUs in knee extensor muscles [(vastus medialis (VM), vastus lateralis (VL) and rectus femoris (RF)] during a sustained contraction at 5% of maximal voluntary contraction for 5 min. In all cases, the spike interval exhibited an elongating trend, and two discharge patterns were observed, continuous discharge and decruitment. In continuous-discharge MUs, the trend slope was steep immediately after the onset of constant force (steep phase), and then became gentle (gentle phase). Decruitments were observed frequently during each phase, and additional MU recruitment was observed throughout the contraction. The mean value of recruitment threshold force did not differ among the extensors. The mean spike interval at the onset of constant-force isometric contractions was shorter in RF than in VL. However, there were no differences in the duration and extent of the elongating trend, decruitment time and recruitment time among the extensors. The electromyogram of the antagonist biceps femoris muscle revealed no compensatory change for extensor activity. These results indicated that at a low force level, the strategy employed by the central nervous system to maintain constant force appears to involve cooperation among elongating trends in the spike interval, decruitment following elongation, and additional MU recruitment in synergistic muscles.

The Perceived Effectiveness of Mentoring by Company Grade Officers in the United States Air Force

DTIC Science & Technology

2007-03-01

indicated receiving mentoring having reported higher levels of career motivation, self efficacy, and career success compared to non-mentored respondents... career success . Journal of Vocational Behavior, 64, 72-91. Defense Manpower Data Center (2003). 2002 status of the armed forces survey- workplace and

Leader Challenge: What Would You Do?

ERIC Educational Resources Information Center

Miller, Chris; Self, Nate; Garven, Sena; Allen, Nate

2011-01-01

Given the complex environment in which the U.S. military operates, leaders at all levels must be prepared for a force that is more responsive to regional combatant commanders needs, better employs joint capabilities, facilitates force packaging and rapid deployment, and fights self contained units in non-linear, non-contiguous battle space. This…

[Improvement of the system of medical equipmet rationing for military units during the wartime].

PubMed

Miroshnichenko, Iu V; Goriachev, A B; Popov, A A; Morgunov, V A; Ryzhikov, M V; Merkulov, A V

2013-07-01

The authors analyze new legal regulatory document--Medical equipment and reserves supply rate for military units and organisations of the Armed Forces of the Russian Federation, developed in the process of modernization of the system of medical equipment rationing for military units. New legal regulatory document was developed with the aim to replace the similar document d.d 1996-1997. The authors came to conclusion that costs of new medical equipment and reserves supply rates are similar to previous rates. At the same time costs new medical equipment supply rates for medical service increased more than 25%. It is related to change of the role of medical service in the system of medical supply of the Armed Forces of the Russian Federation. Modernization of the system of medical equipment supply rates for military unit of the Armed Forces of the Russian Federation, performed for the purpose of medical supplement for military unit in accordance with new state of the Armed Forces of the Russian Federation, allowed to actualize the regulatory framework of medical supply by means of development and adoption of new Supply and reserves rates be the Ministry of defence. Use if these rates will increase effectiveness and quality of medical supply during the wartime, provide a commonality of reserves of medical equipment and maintenance of established level of combat readiness of medical service of the Armed Forces of the Russian Federation.

Fiber networks amplify active stress

PubMed Central

Ronceray, Pierre; Broedersz, Chase P.

2016-01-01

Large-scale force generation is essential for biological functions such as cell motility, embryonic development, and muscle contraction. In these processes, forces generated at the molecular level by motor proteins are transmitted by disordered fiber networks, resulting in large-scale active stresses. Although these fiber networks are well characterized macroscopically, this stress generation by microscopic active units is not well understood. Here we theoretically study force transmission in these networks. We find that collective fiber buckling in the vicinity of a local active unit results in a rectification of stress towards strongly amplified isotropic contraction. This stress amplification is reinforced by the networks’ disordered nature, but saturates for high densities of active units. Our predictions are quantitatively consistent with experiments on reconstituted tissues and actomyosin networks and shed light on the role of the network microstructure in shaping active stresses in cells and tissue. PMID:26921325

EMG analysis tuned for determining the timing and level of activation in different motor units

PubMed Central

Lee, Sabrina S.M.; de Boef Miara, Maria; Arnold, Allison S.; Biewener, Andrew A.; Wakeling, James M.

2011-01-01

Recruitment patterns and activation dynamics of different motor units greatly influence the temporal pattern and magnitude of muscle force development, yet these features are not often considered in muscle models. The purpose of this study was to characterize the recruitment and activation dynamics of slow and fast motor units from electromyographic (EMG) recordings and twitch force profiles recorded directly from animal muscles. EMG and force data from the gastrocnemius muscles of seven goats were recorded during in vivo tendon-tap reflex and in situ nerve stimulation experiments. These experiments elicited EMG signals with significant differences in frequency content (p<0.001). The frequency content was characterized using wavelet and principal components analysis, and optimized wavelets with centre frequencies, 149.94Hz and 323.13Hz, were obtained. The optimized wavelets were used to calculate the EMG intensities and, with the reconstructed twitch force profiles, to derive transfer functions for slow and fast motor units that estimate the activation state of the muscle from the EMG signal. The resulting activation-deactivation time constants gave r values of 0.98 to 0.99 between the activation state and the force profiles. This work establishes a framework for developing improved muscle models that consider the intrinsic properties of slow and fast fibres within a mixed muscle, and that can more accurately predict muscle force output from EMG. PMID:21570317

EMG analysis tuned for determining the timing and level of activation in different motor units.

PubMed

Lee, Sabrina S M; Miara, Maria de Boef; Arnold, Allison S; Biewener, Andrew A; Wakeling, James M

2011-08-01

Recruitment patterns and activation dynamics of different motor units greatly influence the temporal pattern and magnitude of muscle force development, yet these features are not often considered in muscle models. The purpose of this study was to characterize the recruitment and activation dynamics of slow and fast motor units from electromyographic (EMG) recordings and twitch force profiles recorded directly from animal muscles. EMG and force data from the gastrocnemius muscles of seven goats were recorded during in vivo tendon-tap reflex and in situ nerve stimulation experiments. These experiments elicited EMG signals with significant differences in frequency content (p<0.001). The frequency content was characterized using wavelet and principal components analysis, and optimized wavelets with centre frequencies, 149.94 Hz and 323.13 Hz, were obtained. The optimized wavelets were used to calculate the EMG intensities and, with the reconstructed twitch force profiles, to derive transfer functions for slow and fast motor units that estimate the activation state of the muscle from the EMG signal. The resulting activation-deactivation time constants gave r values of 0.98-0.99 between the activation state and the force profiles. This work establishes a framework for developing improved muscle models that consider the intrinsic properties of slow and fast fibres within a mixed muscle, and that can more accurately predict muscle force output from EMG. Copyright © 2011 Elsevier Ltd. All rights reserved.

Resourcing interventions enhance psychology support capabilities in special operations forces.

PubMed

Myatt, Craig A; Auzenne, J W

2012-01-01

This study provides an examination of approaches to United States Government (USG) resourcing interventions on a national scale that enhance psychology support capabilities in the Special Operations Forces (SOF) community. A review of Congressional legislation and resourcing trends in the form of authorizations and appropriations since 2006 demonstrates how Congress supported enhanced psychology support capabilities throughout the Armed Forces and in SOF supporting innovative command interests that address adverse affects of operations tempo behavioral effects (OTBE). The formulation of meaningful metrics to address SOF specific command interests led to a personnel tempo (PERSTEMPO) analysis in response to findings compiled by the Preservation of the Force and Families (POTFF) Task Force. The review of PERSTEMPO data at subordinate command and unit levels enhances the capability of SOF leaders to develop policy and guidance on training and operational planning that mitigates OTBE and maximizes resourcing authorizations. A major challenge faced by the DoD is in providing behavioral healthcare that meets public and legislative demands while proving suitable and sustainable at all levels of military operations: strategic, operational, and tactical. Current legislative authorizations offer a mechanism of command advocacy for resourced multi-functional program development that enhances psychology support capabilities while reinforcing SOF readiness and performance. 2012.

A Quarter Century of Changes in the Elementary and Secondary Teaching Force: From 1987 to 2012. Statistical Analysis Report. NCES 2017-092

ERIC Educational Resources Information Center

Ingersoll, Richard; Merrill, Lisa

2017-01-01

This report utilizes the nationally representative Schools and Staffing Survey (SASS) to examine changes in the elementary and secondary teaching force in the United States over the quarter century from 1987-88 to 2011-12. The report focuses on three key demographic characteristics: the size of the teaching force, the level of teaching experience…

Global and Regional Sea Level Rise Scenarios for the United States

NASA Technical Reports Server (NTRS)

Sweet, William V.; Kopp, Robert E.; Weaver, Christopher P.; Obeysekera, Jayantha; Horton, Radley M.; Thieler, E. Robert; Zervas, Chris

2017-01-01

The Sea Level Rise and Coastal Flood Hazard Scenarios and Tools Interagency Task Force, jointly convened by the U.S. Global Change Research Program (USGCRP) and the National Ocean Council (NOC), began its work in August 2015. The Task Force has focused its efforts on three primary tasks: 1) updating scenarios of global mean sea level (GMSL) rise, 2) integrating the global scenarios with regional factors contributing to sea level change for the entire U.S. coastline, and 3) incorporating these regionally appropriate scenarios within coastal risk management tools and capabilities deployed by individual agencies in support of the needs of specific stakeholder groups and user communities. This technical report focuses on the first two of these tasks and reports on the production of gridded relative sea level (RSL, which includes both ocean-level change and vertical land motion) projections for the United States associated with an updated set of GMSL scenarios. In addition to supporting the longer-term Task Force effort, this new product will be an important input into the USGCRP Sustained Assessment process and upcoming Fourth National Climate Assessment (NCA4) due in 2018. This report also serves as a key technical input into the in-progress USGCRP Climate Science Special Report (CSSR).

Recruitment of rat diaphragm motor units across motor behaviors with different levels of diaphragm activation.

PubMed

Seven, Yasin B; Mantilla, Carlos B; Sieck, Gary C

2014-12-01

Phrenic motor neurons are recruited across a range of motor behaviors to generate varying levels of diaphragm muscle (DIAm) force. We hypothesized that DIAm motor units are recruited in a fixed order across a range of motor behaviors of varying force levels, consistent with the Henneman Size Principle. Single motor unit action potentials and compound DIAm EMG activities were recorded in anesthetized, neurally intact rats across different motor behaviors, i.e., eupnea, hypoxia-hypercapnia (10% O2 and 5% CO2), deep breaths, sustained airway occlusion, and sneezing. Central drive [estimated by root-mean-squared (RMS) EMG value 75 ms after the onset of EMG activity (RMS75)], recruitment delay, and onset discharge frequencies were similar during eupnea and hypoxia-hypercapnia. Compared with eupnea, central drive increased (∼25%) during deep breaths, and motor units were recruited ∼12 ms earlier (P < 0.01). During airway occlusion, central drive was ∼3 times greater, motor units were recruited ∼30 ms earlier (P < 0.01), and motor unit onset discharge frequencies were significantly higher (P < 0.01). Recruitment order of motor unit pairs observed during eupnea was maintained for 98%, 87%, and 84% of the same pairs recorded during hypoxia-hypercapnia, deep breaths, and airway occlusion, respectively. Reversals in motor unit recruitment order were observed primarily if motor unit pairs were recruited <20 ms apart. These results are consistent with DIAm motor unit recruitment order being determined primarily by the intrinsic size-dependent electrophysiological properties of phrenic motor neurons. Copyright © 2014 the American Physiological Society.

Recruitment of rat diaphragm motor units across motor behaviors with different levels of diaphragm activation

PubMed Central

Seven, Yasin B.; Mantilla, Carlos B.

2014-01-01

Phrenic motor neurons are recruited across a range of motor behaviors to generate varying levels of diaphragm muscle (DIAm) force. We hypothesized that DIAm motor units are recruited in a fixed order across a range of motor behaviors of varying force levels, consistent with the Henneman Size Principle. Single motor unit action potentials and compound DIAm EMG activities were recorded in anesthetized, neurally intact rats across different motor behaviors, i.e., eupnea, hypoxia-hypercapnia (10% O2 and 5% CO2), deep breaths, sustained airway occlusion, and sneezing. Central drive [estimated by root-mean-squared (RMS) EMG value 75 ms after the onset of EMG activity (RMS75)], recruitment delay, and onset discharge frequencies were similar during eupnea and hypoxia-hypercapnia. Compared with eupnea, central drive increased (∼25%) during deep breaths, and motor units were recruited ∼12 ms earlier (P < 0.01). During airway occlusion, central drive was ∼3 times greater, motor units were recruited ∼30 ms earlier (P < 0.01), and motor unit onset discharge frequencies were significantly higher (P < 0.01). Recruitment order of motor unit pairs observed during eupnea was maintained for 98%, 87%, and 84% of the same pairs recorded during hypoxia-hypercapnia, deep breaths, and airway occlusion, respectively. Reversals in motor unit recruitment order were observed primarily if motor unit pairs were recruited <20 ms apart. These results are consistent with DIAm motor unit recruitment order being determined primarily by the intrinsic size-dependent electrophysiological properties of phrenic motor neurons. PMID:25257864

Army Reserve Components Research Roadmap Volume 2: Research Agenda

DTIC Science & Technology

1997-09-01

over a 150-mile radius. This obviously makes training above the company level difficult for any time other than annual training (AT). In addition...at a higher level of decision- making , fluidity in the assignments of force structures to units creates wide spread change which affects whole units...can increasingly make TADSS and other enhancements practical solutions to persistent training needs. It should also be noted that the questions

Consolidated fuel reprossing program: The implications of force reflection for teleoperation in space

NASA Technical Reports Server (NTRS)

Draper, John V.; Herndon, Joseph N.; Moore, Wendy E.

1987-01-01

Previous research on teleoperator force feedback is reviewed and results of a testing program which assessed the impact of force reflection on teleoperator task performance are reported. Force relection is a type of force feedback in which the forces acting on the remote portion of the teleoperator are displayed to the operator by back-driving the master controller. The testing program compared three force reflection levels: 4 to 1 (four units of force on the slave produce one unit of force at the master controller), 1 to 1, and infinity to 1 (no force reflection). Time required to complete tasks, rate of occurrence of errors, the maximum force applied to tasks components, and variability in forces applied to components during completion of representative remote handling tasks were used as dependent variables. Operators exhibited lower error rates, lower peak forces, and more consistent application of forces using force relection than they did without it. These data support the hypothesis that force reflection provides useful information for teleoperator users. The earlier literature and the results of the experiment are discussed in terms of their implications for space based teleoperator systems. The discussion described the impact of force reflection on task completion performance and task strategies, as suggested by the literature. It is important to understand the trade-offs involved in using telerobotic systems with and without force reflection.

Understanding USSOCOM and US Marine Corps Roles in Crisis Response and Limited Contingency Operations

DTIC Science & Technology

2013-04-15

are required. For example exploring MAGTF deployments on Littoral Combat Ships or building GCE , LCE, and ACE units that support company level ...objective raids that is likely due to the level of training and in the case of peace enforcement it is likely due to the regional focus of SOF...formed the SOF units and task forces over this period. The inherent “jointness” of USSOCOM is apparent at the lowest tactical level which contrasts

Global and regional sea level rise scenarios for the United States

USGS Publications Warehouse

Sweet, W.; Kopp, R.E.; Weaver, C.P.; Obeysekera, J; Horton, Radley M.; Thieler, E. Robert; Zervas, C.

2017-01-01

level (RSL, which includes both ocean-level change and vertical land motion) projections for the United States associated with an updated set of GMSL scenarios. In addition to supporting the longer-term Task Force effort, this new product will be an important input into the USGCRP Sustained Assessment process and upcoming Fourth National Climate Assessment (NCA4) due in 2018. This report also serves as a keytechnical input into the in-progress USGCRP Climate Science Special Report (CSSR).

Relative contribution of different altered motor unit control to muscle weakness in stroke: a simulation study

NASA Astrophysics Data System (ADS)

Shin, Henry; Suresh, Nina L.; Zev Rymer, William; Hu, Xiaogang

2018-02-01

Objective. Chronic muscle weakness impacts the majority of individuals after a stroke. The origins of this hemiparesis is multifaceted, and an altered spinal control of the motor unit (MU) pool can lead to muscle weakness. However, the relative contribution of different MU recruitment and discharge organization is not well understood. In this study, we sought to examine these different effects by utilizing a MU simulation with variations set to mimic the changes of MU control in stroke. Approach. Using a well-established model of the MU pool, this study quantified the changes in force output caused by changes in MU recruitment range and recruitment order, as well as MU firing rate organization at the population level. We additionally expanded the original model to include a fatigue component, which variably decreased the output force with increasing length of contraction. Differences in the force output at both the peak and fatigued time points across different excitation levels were quantified and compared across different sets of MU parameters. Main results. Across the different simulation parameters, we found that the main driving factor of the reduced force output was due to the compressed range of MU recruitment. Recruitment compression caused a decrease in total force across all excitation levels. Additionally, a compression of the range of MU firing rates also demonstrated a decrease in the force output mainly at the higher excitation levels. Lastly, changes to the recruitment order of MUs appeared to minimally impact the force output. Significance. We found that altered control of MUs alone, as simulated in this study, can lead to a substantial reduction in muscle force generation in stroke survivors. These findings may provide valuable insight for both clinicians and researchers in prescribing and developing different types of therapies for the rehabilitation and restoration of lost strength after stroke.

Finding Your Workforce: The Top 25 Institutions Graduating Latinos in Health Professions and Related Programs by Academic Level. Second in a Series Linking College Completion with U.S. Workforce Needs

ERIC Educational Resources Information Center

Santiago, Deborah A.

2012-01-01

The population growth, labor force participation, and educational attainment of Latinos in the U.S. influence the composition of the current and future U.S. society, economy, and workforce. In 2012, the Latino population in the United States is the youngest and fastest growing ethnic group, with the highest level of labor force participation…

Ambient sound levels at four Department of Interior conservation units in support of Homestead Air Base reuse supplemental environmental impact statement

DOT National Transportation Integrated Search

1999-06-01

The Federal Aviation Administration (FAA), in cooperation with the United States Air Force (USAF), is developing a Supplemental Environmental Impact Statement (SEIS) in support of the planned commercialization of Homestead Air Base in Southern Florid...

Air Force Journal of Logistics. Volume XXIII, Number 4, Winter 1999

DTIC Science & Technology

1999-01-01

needs of the Air Force. 2. Uses existing software developed by base-level Air Force Reserve Command units as a benchmark. MSgt Maura A. Barton, DSN... Maura A. Barton, DSN 596-4581 Follow-on Technical Support for the Weapons Load Crew Management Program LM199812000—Consulting Study 1. Ensures the... Kelly AFB, an aging munitions infrastructure, and current runway restrictions for airlift aircraft make the future of that STAMP location uncertain

Transforming American Education: Reducing the Risk to the Nation. A Report to the Secretary of Education, United States Department of Education, by The National Task Force on Educational Technology.

ERIC Educational Resources Information Center

Ridley, William J.; Hull, McAllister H., Jr.

Designed to assist educational decision-makers at the school and district level, this report summarizes the work of the National Task Force on Educational Technology, which was formed in the fall of 1984 to investigate the potential of appropriately integrated technology for improving learning in American schools. The task force used six primary…

Coexistence of twitch potentiation and tetanic force decline in rat hindlimb muscle

NASA Technical Reports Server (NTRS)

Rankin, Lucinda L.; Enoka, Roger M.; Volz, Kathryn A.; Stuart, Douglas G.

1988-01-01

The effect of whole-muscle fatigue on the isometric twitch was investigated in various hindlimb muscles of anesthetized rats, using an experimental protocol designed to assess the levels of fatigability in motor units. The results of EMG and force measurements revealed the existence of a linear relationship between fatigability and the magnitude of the twitch force following the fatigue test in both soleus and extensor digitorum longus muscles.

Guidelines for cognitive behavioral training within doctoral psychology programs in the United States: report of the Inter-organizational Task Force on Cognitive and Behavioral Psychology Doctoral Education.

PubMed

Klepac, Robert K; Ronan, George F; Andrasik, Frank; Arnold, Kevin D; Belar, Cynthia D; Berry, Sharon L; Christofff, Karen A; Craighead, Linda W; Dougher, Michael J; Dowd, E Thomas; Herbert, James D; McFarr, Lynn M; Rizvi, Shireen L; Sauer, Eric M; Strauman, Timothy J

2012-12-01

The Association for Behavioral and Cognitive Therapies initiated an interorganizational task force to develop guidelines for integrated education and training in cognitive and behavioral psychology at the doctoral level in the United States. Fifteen task force members representing 16 professional associations participated in a year-long series of conferences, and developed a consensus on optimal doctoral education and training in cognitive and behavioral psychology. The recommendations assume solid foundational training that is typical within applied psychology areas such as clinical and counseling psychology programs located in the United States. This article details the background, assumptions, and resulting recommendations specific to doctoral education and training in cognitive and behavioral psychology, including competencies expected in the areas of ethics, research, and practice. Copyright © 2012. Published by Elsevier Ltd.

Influence of proprioceptive feedback on the firing rate and recruitment of motoneurons

PubMed Central

De Luca, C J; Kline, J C

2012-01-01

We investigated the relationships of the firing rate and maximal recruitment threshold of motoneurons recorded during isometric contraction with the number of spindles in individual muscles. At force levels above 10% of maximal voluntary contraction, the firing rate was inversely related to the number of spindles in a muscle, with the slope of the relationship increasing with force. The maximal recruitment threshold of motor units increased linearly with the number of spindles in the muscle. Thus, muscles with a greater number of spindles had lower firing rates and a greater maximal recruitment threshold. These findings may be explained by a mechanical interaction between muscle fibres and adjacent spindles. During low-level (0 to 10%) voluntary contractions, muscle fibres of recruited motor units produce force-twitches that activate nearby spindles to respond with an immediate excitatory feedback that reaches maximal level. As the force increases further, the twitches overlap and tend towards tetanization, the muscle fibres shorten, the spindles slacken, their excitatory firings decrease, and the net excitation to the homonymous motoneurons decreases. Motoneurons of muscles with greater number of spindles receive a greater decrease in excitation which reduces their firing rates, increases their maximal recruitment threshold, and changes the motoneuron recruitment distribution. PMID:22183300

In Service to the Nation: Air Force Research Institute Strategic Concept for 2018-2023

DTIC Science & Technology

2009-01-01

must integrate at every level of operational planning and execution. The key to successful strategic communication lies in understanding that de ...Institute strategic concept for 2018–2023 / John A. Shaud. p. ; cm. Includes bibliographical references. ISBN 978-1-58566-189-3 1. Military planning ...United States. 2. United States—Air Force—Forecasting. 3. Strategic plan - ning—United States—Military aspects. 4. United States—Air Force—Operational

26 CFR 301.7701-8 - Military or naval forces and Armed Forces of the United States.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Military or naval forces and Armed Forces of... § 301.7701-8 Military or naval forces and Armed Forces of the United States. The term “military or naval forces of the United States” and the term “Armed Forces of the United States” each includes all regular...

Symptoms of psychological distress and post-traumatic stress disorder in United States Air Force "drone" operators.

PubMed

Chappelle, Wayne L; McDonald, Kent D; Prince, Lillian; Goodman, Tanya; Ray-Sannerud, Bobbie N; Thompson, William

2014-08-01

The goal of this study is to repeat a survey administered in 2010 to assess for changes in mental health among United States Air Force aircrew operating Predator/Reaper remotely piloted aircraft, also commonly referred to as "drones." Participants were assessed for self-reported sources of occupational stress, levels of clinical distress using the Outcome Questionnaire-45.2, and symptoms of post-traumatic stress disorder (PTSD) using the PTSD Checklist-Military Version. A total of 1,094 aircrew responded to the web-based survey composed of the commercially available standardized instruments mentioned above. The survey also contained nonstandardized items asking participants to report the main sources of their occupational stress, as well as questions addressing demographics and work-related characteristics. The estimated response rate to the survey was 49%. Study results reveal the most problematic self-reported stressors are operational: low manning, extra duties/administrative tasks, rotating shift work, and long hours. The results also reveal 10.72% of operators self-reported experiencing high levels of distress and 1.57% reported high levels of PTSD symptomology. The results are lower than findings from the 2010 survey and from soldiers returning from Iraq and Afghanistan. Implications of the study and recommendations for United States Air Force line leadership and mental health providers are discussed. Reprint & Copyright © 2014 Association of Military Surgeons of the U.S.

Fact Sheet on Women of Spanish Origin in the United States.

ERIC Educational Resources Information Center

Employment Standards Administration (DOL), Washington, DC. Women's Bureau.

March 1971 data are given for women of Spanish origin in the United States. Country of origin, population, family composition, educational attainment, labor force participation, type of work, income, and low income level are covered. Where separate data for women are not available, data for both sexes are shown. (KM)

45 CFR 506.13 - “Armed Forces of the United States” defined.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 45 Public Welfare 3 2010-10-01 2010-10-01 false âArmed Forces of the United Statesâ defined. 506... Prisoners of War § 506.13 “Armed Forces of the United States” defined. Armed Forces of the United States means the United States Air Force, Army, Navy, Marine Corps and Coast Guard, and commissioned officers...

United States Air Force Computer-Aided Acquisition and Logistics Support (CALS) Evolution of Computer Integrated Manufacturing (CIM) Technologies

DTIC Science & Technology

1988-11-01

Manufacturing System 22 4. Similar Parts Based Shape or Manufactuting Process 24 5. Projected Annual Unit Robot Sales and Installed Base Through 1992 30 6. U.S...effort needed to perform personnel, product design, marketing , and advertising, and finance tasks of the firm. Level III controls the resource...planning and accounting functions of the firm. Systems at this level support purchasing, accounts payable, accounts receivable, master scheduling and sales

Perspectives for a new realization of the pascal by optical methods

NASA Astrophysics Data System (ADS)

Jousten, Karl; Hendricks, Jay; Barker, Daniel; Douglas, Kevin; Eckel, Steve; Egan, Patrick; Fedchak, James; Flügge, Jens; Gaiser, Christof; Olson, Douglas; Ricker, Jacob; Rubin, Tom; Sabuga, Wladimir; Scherschligt, Julia; Schödel, Rene; Sterr, Uwe; Stone, Jack; Strouse, Gregory

2017-12-01

Since the beginning of measurement of pressure in the 17th century, the unit of pressure has been defined by the relationship of force per unit area. The present state of optical technology now offers the possibility of using a thermodynamic definition—specifically the ideal gas law—for the realization of the pressure unit, in the vacuum regime and slightly above, with an accuracy comparable to or better than the traditional methods of force per area. The changes planned for the SI in 2018 support the application of this thermodynamic definition that is based on the ideal gas law with the necessary corrections for real-gas effects. The paper reviews the theoretical and experimental foundations of those optical methods that are considered to be most promising to realize the unit of pressure at the highest level of metrology.

Strengthening Sustainability and Resiliency of a Future Force, Phase 1. FY2010-2011 Summer Study

DTIC Science & Technology

2011-03-01

Resiliency of a Future Force: Phase I Interim Report - 48 Please Enter Custom Water factor adjustments below: m Unit Level* (Gat/Ptisan/ Dti ...cost of mov- ing the consumables in terms of the assets required to move the commodity and the security Intra Theater Resupply: 4 Legs Army...Expeditionary Force-Logistics ResupplyDetails Legl Leg 2 Leg 3 Leg 4 Resupply Trip Legs Super FOB (Div)to Base Camp (bde) Base Camp (Bde) to FOB (Bn

Force estimation from ensembles of Golgi tendon organs

NASA Astrophysics Data System (ADS)

Mileusnic, M. P.; Loeb, G. E.

2009-06-01

Golgi tendon organs (GTOs) located in the skeletal muscles provide the central nervous system with information about muscle tension. The ensemble firing of all GTO receptors in the muscle has been hypothesized to represent a reliable measure of the whole muscle force but the precision and accuracy of that information are largely unknown because it is impossible to record activity simultaneously from all GTOs in a muscle. In this study, we combined a new mathematical model of force sampling and transduction in individual GTOs with various models of motor unit (MU) organization and recruitment simulating various normal, pathological and neural prosthetic conditions. Our study suggests that in the intact muscle the ensemble GTO activity accurately encodes force information according to a nonlinear, monotonic relationship that has its steepest slope for low force levels and tends to saturate at the highest force levels. The relationship between the aggregate GTO activity and whole muscle tension under some pathological conditions is similar to one seen in the intact muscle during rapidly modulated, phasic excitation of the motor pool (typical for many natural movements) but quite different when the muscle is activated slowly or held at a given force level. Substantial deviations were also observed during simulated functional electrical stimulation.

Two sensory channels mediate perception of fingertip force.

PubMed

Brothers, Trevor; Hollins, Mark

2014-01-01

In two experiments we examined the ability of humans to exert forces accurately with the fingertips, and to perceive those forces. In experiment 1 participants used visual feedback to apply a range of fingertip forces with the distal pad of the thumb. Participants made magnitude discriminations regarding these forces, and their just noticeable differences were calculated at a series of standards by means of a two-interval, forced-choice tracking paradigm. As the standard increased, participants demonstrated a relative improvement in force discrimination; and the presence of a possible inflection point, at approximately 400 g, suggested that two sensory channels may contribute to performance. If this is the case, the operative channel at low forces is almost certainly the slowly adapting type I (SA-I) channel, while another mechanoreceptor class, the SA-II nail unit, is a plausible mediator of the more accurate performance seen at high force levels. To test this two-channel hypothesis in experiment 2, we hydrated participants' thumbnails in order to reduce nail rigidity and thus prevent stimulation of underlying SA-II mechanoreceptors. This technique was found to reduce sensory accuracy in a force-matching task at high forces (1000 g) while leaving low force matching (100 g) unimpaired. Taken together, these results suggest that two sensory channels mediate the perception of fingertip forces in humans: one channel predominating at low forces (below approximately 400 g) and another responsible for perceiving high forces which is likely mediated by the SA-II nail unit.

78 FR 24439 - Compliance With Information Request, Flooding Hazard Reevaluation

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-25

... to have exceeded 14 meters (45 feet) in height that inundated the Fukushima Dai-ichi nuclear power... earthquake occurred, Fukushima Dai-ichi Units 1, 2, and 3, were in operation and Units 4, 5, and 6, were shut... at the Fukushima Dai-ichi nuclear power plant, the NRC established a senior-level agency task force...

Assessment, Accountability, and Educational Quality in the United States and Sweden

ERIC Educational Resources Information Center

Culver, Steven M.; Warfvinge, Per

2013-01-01

In both Europe and the United States, accountability pressures have continued to increase, spurred by the higher-level policy groups represented by the EC in Europe and by the federal government in the US, forcing institutions to measure their effectiveness in ways that are more transparent to governmental bodies and the general public. These ways…

Leadership, cohesion, morale, and the mental health of UK Armed Forces in Afghanistan.

PubMed

Jones, Norman; Seddon, Rachel; Fear, Nicola T; McAllister, Pete; Wessely, Simon; Greenberg, Neil

2012-01-01

UK Armed Forces (AF) personnel deployed to Afghanistan are frequently exposed to intense combat and yet little is known about the short-term mental health consequences of this exposure and the potential mitigating effects of military factors such as cohesion, morale, and leadership. To assess the possible modulating influence of cohesion, morale, and leadership on post-traumatic stress disorder (PTSD) symptoms and common mental disorders resulting from combat exposure among UK AF personnel deployed to Afghanistan, UK AF personnel, during their deployment to Afghanistan in 2010, completed a self-report survey about aspects of their current deployment, including perceived levels of cohesion, morale, leadership, combat exposure, and their mental health status. Outcomes were symptoms of common mental disorder and symptoms of PTSD. Combat exposure was associated with both PTSD symptoms and symptoms of common mental disorder. Of the 1,431 participants, 17.1% reported caseness levels of common mental disorder, and 2.7% were classified as probable PTSD cases. Greater self-reported levels of unit cohesion, morale, and perceived good leadership were all associated with lower levels of common mental disorder and PTSD. Greater levels of unit cohesion, morale, and good leadership may help to modulate the effects of combat exposure and the subsequent development of mental health problems among UK Armed Forces personnel deployed to Afghanistan. © 2012 Guilford Publications, Inc.

Atmospheric observations for STS-1 landing

NASA Technical Reports Server (NTRS)

Turner, R. E.; Arnold, J. E.; Wilson, G. S.

1981-01-01

A summary of synoptic weather conditions existing over the western United States is given for the time of shuttle descent into Edwards Air Force Base, California. The techniques and methods used to furnish synoptic atmospheric data at the surface and aloft for flight verification of the STS-1 orbiter during its descent into Edwards Air Force Base are specified. Examples of the upper level data set are given.

45 CFR 506.14 - “Force hostile to the United States” defined.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 45 Public Welfare 3 2010-10-01 2010-10-01 false âForce hostile to the United Statesâ defined. 506... Prisoners of War § 506.14 “Force hostile to the United States” defined. Force hostile to the United States means any organization or force in Southeast Asia, or any agent or employee thereof, engaged in any...

Special mobile rescue unit can speed recovery

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1977-04-01

Since time is often a matter of life and death in a mine disaster, Mine Emergency Operations (MEO) personnel are prepared to begin rescue work at any mining site in the eastern part of the United States within six hours of notification, and within no more than nine hours in the western United States. The entire MEO force, including vans, trucks, bulldozers to clear and level the drilling site, seismic equipment, and the big drilling rig can be on any site within less than 20 hours of a disaster. The speed of deployment is made possible in some measure bymore » a special agreement between MESA and the United States Air Force, which stands ready 24 hours a day to dispatch giant C-130 cargo aircraft to airlift the tons of bulky MEO equipment. While the big drilling rig is usually taken to disaster sites by highway, it can also be airlifted when necessary.« less

45 CFR 506.14 - “Force hostile to the United States” defined.

Code of Federal Regulations, 2012 CFR

2012-10-01

... CLAIMS UNDER TITLE I OF THE WAR CLAIMS ACT OF 1948, AS AMENDED ELIGIBILITY REQUIREMENTS FOR COMPENSATION Prisoners of War § 506.14 “Force hostile to the United States” defined. Force hostile to the United States... Forces of the United States during the Vietnam conflict. ...

45 CFR 506.14 - “Force hostile to the United States” defined.

Code of Federal Regulations, 2013 CFR

2013-10-01

... CLAIMS UNDER TITLE I OF THE WAR CLAIMS ACT OF 1948, AS AMENDED ELIGIBILITY REQUIREMENTS FOR COMPENSATION Prisoners of War § 506.14 “Force hostile to the United States” defined. Force hostile to the United States... Forces of the United States during the Vietnam conflict. ...

45 CFR 506.14 - “Force hostile to the United States” defined.

Code of Federal Regulations, 2011 CFR

2011-10-01

... CLAIMS UNDER TITLE I OF THE WAR CLAIMS ACT OF 1948, AS AMENDED ELIGIBILITY REQUIREMENTS FOR COMPENSATION Prisoners of War § 506.14 “Force hostile to the United States” defined. Force hostile to the United States... Forces of the United States during the Vietnam conflict. ...

45 CFR 506.14 - “Force hostile to the United States” defined.

Code of Federal Regulations, 2014 CFR

2014-10-01

... CLAIMS UNDER TITLE I OF THE WAR CLAIMS ACT OF 1948, AS AMENDED ELIGIBILITY REQUIREMENTS FOR COMPENSATION Prisoners of War § 506.14 “Force hostile to the United States” defined. Force hostile to the United States... Forces of the United States during the Vietnam conflict. ...

Quantifying the atomic-level mechanics of single long physisorbed molecular chains.

PubMed

Kawai, Shigeki; Koch, Matthias; Gnecco, Enrico; Sadeghi, Ali; Pawlak, Rémy; Glatzel, Thilo; Schwarz, Jutta; Goedecker, Stefan; Hecht, Stefan; Baratoff, Alexis; Grill, Leonhard; Meyer, Ernst

2014-03-18

Individual in situ polymerized fluorene chains 10-100 nm long linked by C-C bonds are pulled vertically from an Au(111) substrate by the tip of a low-temperature atomic force microscope. The conformation of the selected chains is imaged before and after manipulation using scanning tunneling microscopy. The measured force gradient shows strong and periodic variations that correspond to the step-by-step detachment of individual fluorene repeat units. These variations persist at constant intensity until the entire polymer is completely removed from the surface. Calculations based on an extended Frenkel-Kontorova model reproduce the periodicity and magnitude of these features and allow us to relate them to the detachment force and desorption energy of the repeat units. The adsorbed part of the polymer slides easily along the surface during the pulling process, leading to only small oscillations as a result of the high stiffness of the fluorenes and of their length mismatch with respect to the substrate surface structure. A significant lateral force also is caused by the sequential detachment of individual units. The gained insight into the molecule-surface interactions during sliding and pulling should aid the design of mechanoresponsive nanosystems and devices.

Analysis of surface EMG spike shape across different levels of isometric force.

PubMed

Gabriel, David A; Lester, Steven M; Lenhardt, Sean A; Cambridge, Edward D J

2007-01-15

This research evaluated changes in surface electromyographic (SEMG) spike shape across different levels of isometric force. Ninety-six subjects generated three 5-s isometric step contractions of the elbow flexors at 40, 60, 80, and 100% of maximal voluntary contraction (MVC). Force and bipolar SEMG activity were monitored concurrently. The mean spike amplitude (MSA) exhibited a linear increase across the four levels of force. The mean spike frequency (MSF) remained stable from 40 to 80% of MVC; it then decreased from 80 to 100% of MVC. There was a concomitant increase in mean spike slope (MSS) that indicates that the biceps brachii (BB) relied on the recruitment of higher threshold motor units (MUs) from 40 to 80% of MVC. However, there progressive decrease in the mean number of peaks per spike (MNPPS) that suggests that MU synchronization was additionally required to increase force from 80 to 100% of MVC. The spike shape measures, taken together, indicate that the decrease in frequency content of the signal was due to synchronization, not an increased probability of temporal overlap due an increase in rate-coding.

Force Limited Vibration Test of HESSI Imager

NASA Technical Reports Server (NTRS)

Amato, Deborah; Pankow, David; Thomsen, Knud

2000-01-01

The High Energy Solar Spectroscopic Imager (HESSI) is a solar x-ray and gamma-ray observatory scheduled for launch in November 2000. Vibration testing of the HESSI imager flight unit was performed in August 1999. The HESSI imager consists of a composite metering tube, two aluminum trays mounted to the tube on titanium flexure mounts, and nine modulation grids mounted on each tray. The vibration tests were acceleration controlled and force limited, in order to prevent overtesting. The force limited strategy reduced the shaker force and notched the acceleration at resonances. The test set-up, test levels, and results are presented. The development of the force limits is also discussed. The imager successfully survived the vibration testing.

How suspect race affects police use of force in an interaction over time.

PubMed

Kahn, Kimberly Barsamian; Steele, Joel S; McMahon, Jean M; Stewart, Greg

2017-04-01

Although studies often find racial disparities in policing outcomes, less is known about how suspect race biases police interactions as they unfold. This study examines what is differentially occurring during police-suspect interactions for White, Black, and Latino suspects across time. It is hypothesized that racial bias may be more evident earlier in interactions, when less information about the situation is available. One hundred thirty-nine (62 White, 42 Black, and 35 Latino) use-of-force case files and associated written narratives from a medium to large size urban police department in the United States were analyzed. Trained coders broke down the interaction narratives into discrete "sequences," or dyadic action-reaction steps involving a suspect action (level of resistance) and an officer response (level of force). A linear mixed-effects model was run on amount of police use of force by suspect race and time, with suspect resistance and suspect actions toward third-party/self as controls. Results demonstrated that Black and Latino suspects receive more force in the beginning stages of the interaction, whereas Whites escalated in level of force faster after initial levels. By breaking down police-suspect interactions into discrete sequences, the current study reveals a better understanding of when bias originates in police use of force and informs how to focus policing interventions. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

The Effects of Four Decades of Recession on Higher Education Enrollments in the United States

ERIC Educational Resources Information Center

Wright, Dianne A.; Ramdin, Gianna; Vásquez-Colina, María D.

2013-01-01

The United States experienced six economic recessions between 1970 and 2009. The impact of economic recession on higher education enrollment was examined using seasonally adjusted data from the U.S. Census and the U.S. Department of Labor Bureau of Labor Statistics, Unemployment Level-Civilian Labor Force. One-way analysis of variance, factorial…

Human Rights Law for Persons with Disabilities in Asia and the Pacific: The Need for a Disability Rights Tribunal

ERIC Educational Resources Information Center

Perlin, Michael L.

2013-01-01

Human rights are arguably the most significant political force shaping the life experience of people with disability. The "United Nations Convention on the Rights of Persons with Disabilities" sets the standard at an international level, creating both positive and negative rights, and calls upon member states of the United Nations (UN)…

Childhood Obesity Task Forces Established by State Legislatures, 2001-2010

PubMed Central

Kim, Sonia A.; Sherry, Bettylou; Blanck, Heidi M.

2013-01-01

Introduction States and communities are considering policy and environmental strategies, including enacting legislation, to reduce and prevent childhood obesity. One legislative approach has been to create task forces to understand key issues and develop a course of action. The goal of this study was to describe state-level, childhood obesity task forces in the United States created by legislation from 2001 through 2010. Methods We used the Center for Disease Control and Prevention’s Division of Nutrition, Physical Activity, and Obesity database to identify state-level childhood obesity task forces created through legislation from 2001 through 2010. Results We identified 21 states that had enacted legislation creating childhood obesity task forces of which 6 had created more than one task force. Most task forces were charged with both gathering and reviewing information and making recommendations for obesity-prevention actions in the state. Most legislation required that task forces include representation from the state legislature, state agencies, community organizations, and community members. Conclusion Evaluation of the effectiveness of obesity-prevention task forces and the primary components that contribute to their success may help to determine the advantages of the use of such strategies in obesity prevention. PMID:23987250

The Economic Adjustment of Southeast Asian Refugees in the U.S.

ERIC Educational Resources Information Center

Bach, Robert L.; And Others

Relatively high levels of public assistance use, and low levels of labor force participation among recent arrivals, have focused attention on the ability of refugees to attain self-sufficiency reasonably soon after entering this country. A survey focusing on Southeast Asian refugees resettled in the United States since 1975 indicates that refugees…

Report Task Force on Women in the Military

DTIC Science & Technology

1988-01-01

Education, Training, Equal Opportunity, Assignments. SECURITY CLASSIFICATION OF THIS PAGE ODEPARTMENT OF DEFENSE REPORT TASK FORCE4I ON WOMEN LN THE...ensure that instruction occurs at all levels of the organization; and, DoD review equal opportu- nity lessons learned for use in combating bixual...Servicewomen becoming full and equal members of their units. Each Service should be required to report the results of these evalua- tions and corrective

Functional Mission Analysis (FMA) for the Air Force Cyber Squadron Initiative (CS I)

DTIC Science & Technology

2017-03-17

Analysis for the Air Force Cyber Squadron Initiative DESIGN PROJECT CONDUCTED 13 FEB – 17 FEB 17 Produced with input from numerous units...Success The Air Force’s base-level Communications Squadrons are engaged in a cultural and technological transformation through the Cyber Squadron...sharpening their focus to include active cyber defense and mission assurance as core competencies to enable operational advantages and out-maneuver our

Recruitment and derecruitment characteristics of motor units in a hand muscle of young and old adults.

PubMed

Jesunathadas, Mark; Marmon, Adam R; Gibb, James M; Enoka, Roger M

2010-06-01

The significant decline in motor neuron number after approximately 60 yr of age is accompanied by a remodeling of the neuromuscular system so that average motor unit force increases and the ability of old adults to produce an intended force declines. One possible explanation for the loss of movement precision is that the remodeling increases the difference in recruitment forces between successively recruited motor units in old adults and this augments force variability at motor unit recruitment. The purpose of the study was to compare the forces and discharge characteristics of motor units in a hand muscle of young and old adults at motor unit recruitment and derecruitment. The difference in recruitment force between pairs of motor units did not differ between young (n=54) and old adults (n=56; P=0.702). However, old adults had a greater proportion of contractions in which motor units discharged action potentials transiently before discharging continuously during the ramp increase in force (young: 0.32; old: 0.41; P=0.045). Force variability at motor unit recruitment was greater for old adults compared with young adults (Por=0.729). These results suggest that the difference in force between the recruitment of successive motor units does not differ between age groups, but that motor unit recruitment may be more transient and could contribute to the greater variability in force observed in old adults during graded ramp contractions.

Effects of prolonged vibration to vastus intermedius muscle on force steadiness of knee extensor muscles during isometric force-matching task.

PubMed

Saito, Akira; Ando, Ryosuke; Akima, Hiroshi

2016-12-01

Afferent inputs from Ia fibers in muscle spindles are essential for the control of force and prolonged vibration has been applied to muscle-tendon units to manipulate the synaptic input from Ia afferents onto α-motor neurons. The vastus intermedius (VI) reportedly provides the highest contribution to the low-level knee extension torque among the individual synergists of quadriceps femoris (QF). The purpose of the present study was to examine the effect of prolonged vibration to the VI on force steadiness of the QF. Nine healthy men (25.1±4.3years) performed submaximal force-matching task of isometric knee extension for 15s before and after mechanical vibration to the superficial region of VI for 30min. Target forces were 2.5%, 10%, and 30% of maximal voluntary contraction (MVC), and force steadiness was determined by the coefficient of variation (CV) of force. After the prolonged VI vibration, the CV of force at 2.5%MVC was significantly increased, but CVs at 10% and 30%MVCs were not significantly changed. The present study concluded that application of prolonged vibration to the VI increased force fluctuations of the QF during a very low-level force-matching task. Copyright © 2016 Elsevier Ltd. All rights reserved.

Motor control differs for increasing and releasing force

PubMed Central

Park, Seoung Hoon; Kwon, MinHyuk; Solis, Danielle; Lodha, Neha

2016-01-01

Control of the motor output depends on our ability to precisely increase and release force. However, the influence of aging on force increase and release remains unknown. The purpose of this study, therefore, was to determine whether force control differs while increasing and releasing force in young and older adults. Sixteen young adults (22.5 ± 4 yr, 8 females) and 16 older adults (75.7 ± 6.4 yr, 8 females) increased and released force at a constant rate (10% maximum voluntary contraction force/s) during an ankle dorsiflexion isometric task. We recorded the force output and multiple motor unit activity from the tibialis anterior (TA) muscle and quantified the following outcomes: 1) variability of force using the SD of force; 2) mean discharge rate and variability of discharge rate of multiple motor units; and 3) power spectrum of the multiple motor units from 0–4, 4–10, 10–35, and 35–60 Hz. Participants exhibited greater force variability while releasing force, independent of age (P < 0.001). Increased force variability during force release was associated with decreased modulation of multiple motor units from 35 to 60 Hz (R2 = 0.38). Modulation of multiple motor units from 35 to 60 Hz was further correlated to the change in mean discharge rate of multiple motor units (r = 0.66) and modulation from 0 to 4 Hz (r = −0.64). In conclusion, these findings suggest that force control is altered while releasing due to an altered modulation of the motor units. PMID:26961104

Motor unit recruitment strategies are altered during deep-tissue pain.

PubMed

Tucker, Kylie; Butler, Jane; Graven-Nielsen, Thomas; Riek, Stephan; Hodges, Paul

2009-09-02

Muscle pain is associated with decreased motor unit discharge rate during constant force contractions. As discharge rate is a determinant of force, other adaptations in strategy must explain force maintenance during pain. Our aim was to determine whether motor unit recruitment strategies are altered during pain to maintain force despite reduced discharge rate. Motor unit discharge behavior was recorded in two muscles, one with (quadriceps) and one without [flexor pollicis longus (FPL)] synergists. Motor units were recruited during matched low-force contractions with and without experimentally induced pain, and at higher force without pain. A total of 52 and 34 units were recorded in quadriceps and FPL, respectively, during low-force contractions with and without pain. Of these, 20 quadriceps and 9 FPL units were identified during both trials. The discharge rate of these units reduced during pain in both muscles [quadriceps: 8.7 (1.5) to 7.5 (1.3) Hz, p < 0.001; FPL: 11.9 (1.5) to 10.0 (1.7) Hz, p < 0.001]. All remaining units discharged only with or without pain, but not in both conditions. Only one-third of the additional units recruited during pain (quadriceps n = 7/19, FPL n = 3/15) were those expected given orderly recruitment of the motor unit pool as determined during higher-force contractions. We conclude that reduced motor unit discharge rate with pain is accompanied by changes in the population of units used to maintain force. The recruitment of new units is partly inconsistent with generalized inhibition of the motoneuron pool predicted by the "pain adaptation" theory, and provides the basis for a new mechanism of motor adaptation with pain.

Development of a Force Measurement Device for Lower-Body Muscular Strength Measuring of Skaters

NASA Astrophysics Data System (ADS)

Kim, Dong Ki; Lee, Jeong Tae

This paper presents a force measurement system that can measure a lower-body muscular strength of skaters. The precise measurement and analysis of the left and right lower-body strength of skaters is necessary, because a left/right lower-body strength balance is helpful to improve the athletes' performance and to protect them from injury. The system is constructed with a skate sliding board, a couple of sensor-units with load cell, indicator and control box, guard, force pad, and support bracket. The developed force measurement system is calibrated by the calibration setup, and the uncertainty of the force sensing unit on the left is within 0.087% and the uncertainty of the force sensing unit on the right is within 0.109%. In order to check the feasibility of the developed measurement device, a kinematic analysis is conducted with skater. As a result, the subject shows the deviation of left and right of 12.1 N with respect to average strength and 39.1 N with respect to the maximum strength. This evaluation results are reliable enough to make it possible to measure a lower-body muscular strength of skaters. The use of this measurement system will be expected to correct the posture of skaters and record the sports dynamics data for each athlete. It is believed that through the development of this equipment, skaters in elementary, middle, high schools, colleges, and the professional level have the systematic training to compete with world-class skaters.

Time-related changes in firing rates are influenced by recruitment threshold and twitch force potentiation in the first dorsal interosseous.

PubMed

Miller, Jonathan D; Herda, Trent J; Trevino, Michael A; Sterczala, Adam J; Ciccone, Anthony B

2017-08-01

What is the central question of this study? The influences of motor unit recruitment threshold and twitch force potentiation on the changes in firing rates during steady-force muscular contractions are not well understood. What is the main finding and its importance? The behaviour of motor units during steady force was influenced by recruitment threshold, such that firing rates decreased for lower-threshold motor units but increased for higher-threshold motor units. In addition, individuals with greater changes in firing rates possessed greater twitch force potentiation. There are contradictory reports regarding changes in motor unit firing rates during steady-force contractions. Inconsistencies are likely to be the result of previous studies disregarding motor unit recruitment thresholds and not examining firing rates on a subject-by-subject basis. It is hypothesized that firing rates are manipulated by twitch force potentiation during contractions. Therefore, in this study we examined time-related changes in firing rates at steady force in relationship to motor unit recruitment threshold in the first dorsal interosseous and the influence of twitch force potentiation on such changes in young versus aged individuals. Subjects performed a 12 s steady-force contraction at 50% maximal voluntary contraction, with evoked twitches before and after the contraction to quantify potentiation. Firing rates, in relationship to recruitment thresholds, were determined at the beginning, middle and end of the steady force. There were no firing rate changes for aged individuals. For the young, firing rates decreased slightly for lower-threshold motor units but increased for higher-threshold motor units. Twitch force potentiation was greater for young than aged subjects, and changes in firing rates were correlated with twitch force potentiation. Thus, individuals with greater increases in firing rates of higher-threshold motor units and decreases in lower-threshold motor units possessed greater twitch force potentiation. Overall, changes in firing rates during brief steady-force contractions are dependent on recruitment threshold and explained in part by twitch force potentiation. Given that firing rate changes were measured in relationship to recruitment threshold, this study illustrates a more complete view of firing rate changes during steady-force contractions. © 2017 The Authors. Experimental Physiology © 2017 The Physiological Society.

Modification and optimization of the united-residue (UNRES) potential-energy function for canonical simulations. I. Temperature dependence of the effective energy function and tests of the optimization method with single training proteins

PubMed Central

Liwo, Adam; Khalili, Mey; Czaplewski, Cezary; Kalinowski, Sebastian; Ołdziej, Stanisław; Wachucik, Katarzyna; Scheraga, Harold A.

2011-01-01

We report the modification and parameterization of the united-residue (UNRES) force field for energy-based protein-structure prediction and protein-folding simulations. We tested the approach on three training proteins separately: 1E0L (β), 1GAB (α), and 1E0G (α + β). Heretofore, the UNRES force field had been designed and parameterized to locate native-like structures of proteins as global minima of their effective potential-energy surfaces, which largely neglected the conformational entropy because decoys composed of only lowest-energy conformations were used to optimize the force field. Recently, we developed a mesoscopic dynamics procedure for UNRES, and applied it with success to simulate protein folding pathways. How ever, the force field turned out to be largely biased towards α-helical structures in canonical simulations because the conformational entropy had been neglected in the parameterization. We applied the hierarchical optimization method developed in our earlier work to optimize the force field, in which the conformational space of a training protein is divided into levels each corresponding to a certain degree of native-likeness. The levels are ordered according to increasing native-likeness; level 0 corresponds to structures with no native-like elements and the highest level corresponds to the fully native-like structures. The aim of optimization is to achieve the order of the free energies of levels, decreasing as their native-likeness increases. The procedure is iterative, and decoys of the training protein(s) generated with the energy-function parameters of the preceding iteration are used to optimize the force field in a current iteration. We applied the multiplexing replica exchange molecular dynamics (MREMD) method, recently implemented in UNRES, to generate decoys; with this modification, conformational entropy is taken into account. Moreover, we optimized the free-energy gaps between levels at temperatures corresponding to a predominance of folded or unfolded structures, as well as to structures at the putative folding-transition temperature, changing the sign of the gaps at the transition temperature. This enabled us to obtain force fields characterized by a single peak in the heat capacity at the transition temperature. Furthermore, we introduced temperature dependence to the UNRES force field; this is consistent with the fact that it is a free-energy and not a potential-energy function. PMID:17201450

Key Personnel and Organizations of the Soviet Military High Command.

DTIC Science & Technology

1987-04-01

Europe--the Group of Soviet Forces Germany, Northern Group of Forces ( Poland ), Central Group of Forces (Czechoslovakia), and Southern Group of Forces...units of the groups of Soviet forces in the GDR, Poland , and Czechoslovakia; the air and ground force units from the Baltic, Belorussian, and Carpathian...military districts; the naval units of the Baltic Fleet; and the air, ground, and naval forces of the GDR, Poland , and Czechoslovakia (see Fig. 5a

Change champions at the grassroots level: practice innovation using team process.

PubMed

Scott, J; Rantz, M

1994-01-01

A nursing administrative group recognized the critical value of staff participation in the formulation of a restructuring project and guidance throughout the project. Using a team approach, a task force of three staff nurses, two assistant nurse managers, a nurse clinician, a nursing practice specialist, and a representative from nursing administration came together. They were given responsibility for researching and setting the course for restructuring change. A unit-based team including a unit secretary, a nursing attendant, licensed practical nurse (LPN), and six staff nurses was formed from volunteers from the 40-bed medicine unit to develop that unit's plan for restructuring. The unit-based team analyzed patient care needs and staff member roles. They created a new patient care technician role as well as a nurse care coordinator role. The role of the LPN was envisioned as providing technical support. Staffing mix was also determined by the unit-based team. Both the task force and the unit-based team continue to evaluate, troubleshoot, and take every opportunity to sell their vision to solidify it further as the foundation for the future of patient care services at the hospital. The process will soon move forward to a large surgical unit.

A Review of Anthropometric Data of German Air Force and United States Air Force Flying Personnel 1967-1968

DTIC Science & Technology

1975-04-01

Circ. Level (r.) 9. Radialn (r.) 10. Lower Arm Circ. Level (r.) 11. Stylion (r.) 12. Base of Hand (r.) 13. -ase of Thumb (r.) 14. Glabella 15. Min...the skin ,rease at the proximal edge of the palm. BASE OF THUMB - the point at which the extended base of the hand line intersects the radial borter...BONE the small bone of the hand just distal to the bend of the wrist or the base of the thumb . NECK POINT the point marking the intersection of the

Object/Shape Recognition Technology: An Assessment of the Feasibility of Implementation at Defense Logistics Agency Disposition Services

DTIC Science & Technology

2015-02-25

provide efficiency and effectively manufacture or inventory items. The industries that benefit from Cognex technology are automotive, food and beverage ...recognition tedmology, Tedmology Readiness Level, PAGES Cost Benefit Analysis, Tedmology Commercialization, Technology Transition 139 16. PRICE CODE 17...Technology Development & Transition Strategy Guidebook xvii UD Ultimate Disposal U.S. United States USAF United States Air Force xviii THIS

Train as You Will Fight: Factors Affecting Development of a Strategy to Train National Guard Units to the Level Organized

DTIC Science & Technology

1990-01-01

and Colorado National Guard proved itself through a series of successful operations in the North African campaign, General George S. Patton...prior to deployment into the North African Theater and to its employment as a homogenous unit. A look at how other National Guard units have been used in...the Army. RESERVE COMPONENT IMPACT ON THE TOTAL FORCE FM 100-5, Operations, the Army’s keystone warfighting manual charges that *rigorous, realistic

Collective Training and Fielding Opportunities for the Objective Force Maneuver Systems at the Unit of Action Level in a Unit Manning/Unit Replacement Personnel System

DTIC Science & Technology

2003-04-07

PERSON Rife, Dave RifeD@awc.carlisle.army.mil a. REPORT Unclassified b. ABSTRACT Unclassified c. THIS PAGE Unclassified 19b. TELEPHONE NUMBER International...38 WORD COUNT = 8975 39 40 ENDNOTES 1 COL Pete Zielinski , Director, Joint/Army concepts HQs TRADOC “Transformation Update” briefing slide #9, Briefing...Staff. Interviewed by author, 18 February 2003, Carlisle Barracks, PA. Zielinski , Pete, COL Director, Joint/Army concepts HQs TRADOC “Transformation

Adult mouse motor units develop almost all of their force in the subprimary range: a new all-or-none strategy for force recruitment?

PubMed

Manuel, Marin; Heckman, C J

2011-10-19

Classical studies of the mammalian neuromuscular system have shown an impressive adaptation match between the intrinsic properties of motoneurons and the contractile properties of their motor units. In these studies, the rate at which motoneurons start to fire repetitively corresponds to the rate at which individual twitches start to sum, and the firing rate increases linearly with the amount of excitation ("primary range") up to the point where the motor unit develops its maximal force. This allows for the gradation of the force produced by a motor unit by rate modulation. In adult mouse motoneurons, however, we recently described a regime of firing ("subprimary range") that appears at lower excitation than what is required for the primary range, a finding that might challenge the classical conception. To investigate the force production of mouse motor units, we simultaneously recorded, for the first time, the motoneuron discharge elicited by intracellular ramps of current and the force developed by its motor unit. We showed that the motor unit developed nearly its maximal force during the subprimary range. This was found to be the case regardless of the input resistance of the motoneuron, the contraction speed, or the tetanic force of the motor unit. Our work suggests that force modulation in small mammals mainly relies on the number of motor units that are recruited rather than on rate modulation of individual motor units.

Nuclear-effects model embedded stochastically in simulation (NEMESIS) summary report. Technical paper

DOE Office of Scientific and Technical Information (OSTI.GOV)

Youngren, M.A.

1989-11-01

An analytic probability model of tactical nuclear warfare in the theater is presented in this paper. The model addresses major problems associated with representing nuclear warfare in the theater. Current theater representations of a potential nuclear battlefield are developed in context of low-resolution, theater-level models or scenarios. These models or scenarios provide insufficient resolution in time and space for modeling a nuclear exchange. The model presented in this paper handles the spatial uncertainty in potentially targeted unit locations by proposing two-dimensional multivariate probability models for the actual and perceived locations of units subordinate to the major (division-level) units represented inmore » theater scenarios. The temporal uncertainty in the activities of interest represented in our theater-level Force Evaluation Model (FORCEM) is handled through probability models of the acquisition and movement of potential nuclear target units.« less

Ia Afferent input alters the recruitment thresholds and firing rates of single human motor units.

PubMed

Grande, G; Cafarelli, E

2003-06-01

Vibration of the patellar tendon recruits motor units in the knee extensors via excitation of muscle spindles and subsequent Ia afferent input to the alpha-motoneuron pool. Our first purpose was to determine if the recruitment threshold and firing rate of the same motor unit differed when recruited involuntarily via reflex or voluntarily via descending spinal pathways. Although Ia input is excitatory to the alpha-motoneuron pool, it has also been shown paradoxically to inhibit itself. Our second purpose was to determine if vibration of the patellar tendon during a voluntary knee extension causes a change in the firing rate of already recruited motor units. In the first protocol, 10 subjects voluntarily reproduced the same isometric force profile of the knee extensors that was elicited by vibration of the patellar tendon. Single motor unit recordings from the vastus lateralis (VL) were obtained with tungsten microelectrodes and unitary behaviour was examined during both reflex and voluntary knee extensions. Recordings from 135 single motor units showed that both recruitment thresholds and firing rates were lower during reflex contractions. In the second protocol, 7 subjects maintained a voluntary knee extension at 30 N for approximately 40-45 s. Three bursts of patellar tendon vibration were superimposed at regular intervals throughout the contraction and changes in the firing rate of already recruited motor units were examined. A total of 35 motor units were recorded and each burst of superimposed vibration caused a momentary reduction in the firing rates and recruitment of additional units. Our data provide evidence that Ia input modulates the recruitment thresholds and firing rates of motor units providing more flexibility within the neuromuscular system to grade force at low levels of force production.

58. Photocopy of Architectural Layout drawing, dated 25 June, 1993 ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

58. Photocopy of Architectural Layout drawing, dated 25 June, 1993 by US Air Force Space Command. Original drawing property of United States Air Force, 21" Space Command. AL-5 PAVE PAWS SUPPORT SYSTEMS - CAPE COD AFB, MASSACHUSETTS - LAYOUT 3RD, 3A, 4TH LEVELS. DRAWING NO. AL-5 - SHEET 6 OF 21 - Cape Cod Air Station, Technical Facility-Scanner Building & Power Plant, Massachusetts Military Reservation, Sandwich, Barnstable County, MA

Approximate Dynamic Programming Algorithms for United States Air Force Officer Sustainment

DTIC Science & Technology

2015-03-26

level of correction needed. While paying bonuses has an easily calculable cost, RIFs have more subtle costs. Mone (1994) discovered that in a steady...a regression is performed utilizing instrumental variables to minimize Bellman error. This algorithm uses a set of basis functions to approximate the...transitioned to an all-volunteer force. Charnes et al. (1972) utilize a goal programming model for General Schedule civilian manpower management in the

U.S. Force Posture Strategy in the Asia Pacific Region: An Independent Assessment

DTIC Science & Technology

2012-06-27

the United States, rebalancing efforts after Operations Enduring Freedom and Iraqi Freedom/New Dawn have several benefits, allowing the Army to...of the March 2011 disaster at Fukushima , though a territorial dispute over islands north of Hokkaido continues to hinder bilateral cooperation...with a report due 180 days after enactment, or by the end of June, 2012. At one level, PACOM force posture is tied to current deployments and

The United States Air Force in Southeast Asia: Tactical Airlift

DTIC Science & Technology

1983-01-01

in the upper panhandle, resulted in near- disaster . Ten Air Force and eight Air America helicopters successfully inserted the two hundred- man assault...details at squadron level, and the dilemma of the leader tempering his zeal for the mission with the knowledge that one accident resulting from poor...one hundred resupply flights daily. Twenty French battalions in Laos. meanwhile, became entirely dependent on air supply as a result of fresh

The Next Lightweight Fighter: Not Your Grandfather’s Combat Aircraft

DTIC Science & Technology

2013-08-01

devastat- ing Arabian quake in Somalia, which has almost no infrastructure and suffers from ongoing clan warfare. The United States deployed forces to...Kassim, which the quake had virtually leveled. A joint task force based in Djibouti stood up to direct the relief effort, exercising airborne com- mand...the earth prevent low-altitude or dis- tant aircraft from looking into “the next valley” directly. Consequently, many a reconnaissance mission or

Early emergence of anthropogenically forced heat waves in the western United States and Great Lakes

NASA Astrophysics Data System (ADS)

Lopez, Hosmay; West, Robert; Dong, Shenfu; Goni, Gustavo; Kirtman, Ben; Lee, Sang-Ki; Atlas, Robert

2018-05-01

Climate projections for the twenty-first century suggest an increase in the occurrence of heat waves. However, the time at which externally forced signals of anthropogenic climate change (ACC) emerge against background natural variability (time of emergence (ToE)) has been challenging to quantify, which makes future heat-wave projections uncertain. Here we combine observations and model simulations under present and future forcing to assess how internal variability and ACC modulate US heat waves. We show that ACC dominates heat-wave occurrence over the western United States and Great Lakes regions, with ToE that occurred as early as the 2020s and 2030s, respectively. In contrast, internal variability governs heat waves in the northern and southern Great Plains, where ToE occurs in the 2050s and 2070s; this later ToE is believed to be a result of a projected increase in circulation variability, namely the Great Plain low-level jet. Thus, greater mitigation and adaptation efforts are needed in the Great Lakes and western United States regions.

Synchronization of motor unit firings: an epiphenomenon of firing rate characteristics not common inputs

PubMed Central

Kline, Joshua C.

2015-01-01

Synchronous motor unit firing instances have been attributed to anatomical inputs shared by motoneurons. Yet, there is a lack of empirical evidence confirming the notion that common inputs elicit synchronization under voluntary conditions. We tested this notion by measuring synchronization between motor unit action potential trains (MUAPTs) as their firing rates progressed within a contraction from a relatively low force level to a higher one. On average, the degree of synchronization decreased as the force increased. The common input notion provides no empirically supported explanation for the observed synchronization behavior. Therefore, we investigated a more probable explanation for synchronization. Our data set of 17,546 paired MUAPTs revealed that the degree of synchronization varies as a function of two characteristics of the motor unit firing rate: the similarity and the slope as a function of force. Both are measures of the excitation of the motoneurons. As the force generated by the muscle increases, the firing rate slope decreases, and the synchronization correspondingly decreases. Different muscles have motor units with different firing rate characteristics and display different amounts of synchronization. Although this association is not proof of causality, it consistently explains our observations and strongly suggests further investigation. So viewed, synchronization is likely an epiphenomenon, subject to countless unknown neural interactions. As such, synchronous firing instances may not be the product of a specific design and may not serve a specific physiological purpose. Our explanation for synchronization has the advantage of being supported by empirical evidence, whereas the common input does not. PMID:26490288

Synchronization of motor unit firings: an epiphenomenon of firing rate characteristics not common inputs.

PubMed

Kline, Joshua C; De Luca, Carlo J

2016-01-01

Synchronous motor unit firing instances have been attributed to anatomical inputs shared by motoneurons. Yet, there is a lack of empirical evidence confirming the notion that common inputs elicit synchronization under voluntary conditions. We tested this notion by measuring synchronization between motor unit action potential trains (MUAPTs) as their firing rates progressed within a contraction from a relatively low force level to a higher one. On average, the degree of synchronization decreased as the force increased. The common input notion provides no empirically supported explanation for the observed synchronization behavior. Therefore, we investigated a more probable explanation for synchronization. Our data set of 17,546 paired MUAPTs revealed that the degree of synchronization varies as a function of two characteristics of the motor unit firing rate: the similarity and the slope as a function of force. Both are measures of the excitation of the motoneurons. As the force generated by the muscle increases, the firing rate slope decreases, and the synchronization correspondingly decreases. Different muscles have motor units with different firing rate characteristics and display different amounts of synchronization. Although this association is not proof of causality, it consistently explains our observations and strongly suggests further investigation. So viewed, synchronization is likely an epiphenomenon, subject to countless unknown neural interactions. As such, synchronous firing instances may not be the product of a specific design and may not serve a specific physiological purpose. Our explanation for synchronization has the advantage of being supported by empirical evidence, whereas the common input does not. Copyright © 2016 the American Physiological Society.

Retention and Advancement in the Retail Industry: A Career Ladder Approach.

ERIC Educational Resources Information Center

Prince, Heath J.

Retailing is the largest industry in the United States, employing roughly 18 percent of the total labor force. However, high turnover resulting from low wages in entry-level positions and the perceptions of retail workers that job security is far from certain and that advancement potential is limited have resulted in low levels of employee…

A Comparison of Glide Force Characteristics Between 2 Prefilled Insulin Lispro Pens

PubMed Central

Lennartz, Amanda H.; Ignaut, Debra A.

2015-01-01

Background: Glide force, average glide force, and glide force variability of the insulin lispro 200 units/mL pen (Eli Lilly and Company, Indianapolis, IN, USA) were compared to the Humalog® KwikPen® 100 units/mL pen (hereafter, KwikPen; Eli Lilly and Company, Indianapolis, IN, USA). Methods: Data were collected on 2 doses, 2 injection speeds, and 2 needle types. Results: Insulin lispro 200 units/mL pen showed significantly lower maximum glide force, average glide force, and glide force variability than the KwikPen across all combinations of dose size, dose speed, and needle type. Conclusions: The lower glide force observed with the insulin lispro 200 units/mL pen offers another treatment option for patients with type 1 or type 2 diabetes who require greater than 20 units of mealtime insulin daily. PMID:25591858

Internal development of vegetative buds of Norway spruce trees in relation to accumulated chilling and forcing temperatures.

PubMed

Viherä-Aarnio, Anneli; Sutinen, Sirkka; Partanen, Jouni; Häkkinen, Risto

2014-05-01

The timing of budburst of temperate trees is known to be controlled by complicated interactions of temperature and photoperiod. To improve the phenological models of budburst, better knowledge of the internal bud development preceding budburst in relation to environmental cues is needed. We studied the effect of accumulated chilling and forcing temperatures on the internal development of vegetative buds preceding budburst in Norway spruce [Picea abies (L.) Karst.]. Branches from 17-year-old trees of southern Finnish origin were transferred eight times at 1- to 2-week intervals from October to December 2007 from the field at Punkaharju (61°48'N, 29°20'E) to the greenhouse with forcing conditions (day length 12 h, +20 °C). After seven different durations of forcing, the developmental phase and primordial shoot growth of the buds were analysed at the stereomicroscopic level. Air temperature was recorded hourly throughout the study period. The accumulated chilling unit sum had a significant effect on the temperature sum that was required to attain a certain developmental phase; a higher amount of chilling required a lower amount of forcing. The variation in the rate of development of different buds within each sample branch in relation to the chilling unit and forcing temperature sum was low. Regarding primordial shoot growth, there was also an inverse relation between accumulated chilling and forcing, i.e., a higher accumulated chilling unit sum before forcing required a lower temperature sum to initiate primordial shoot growth and resulted in a stronger effect of accumulated forcing. A second-order regression model with an interaction of chilling and forcing explained the variation of primordial shoot growth with high precision (R(2) = 0.88). However, further studies are required to determine the final parameter values to be used in phenological modelling. © The Author 2014. Published by Oxford University Press. All rights reserved.

32 CFR 989.29 - Force structure and unit move proposals.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 6 2010-07-01 2010-07-01 false Force structure and unit move proposals. 989.29 Section 989.29 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE ENVIRONMENTAL PROTECTION ENVIRONMENTAL IMPACT ANALYSIS PROCESS (EIAP) § 989.29 Force structure and unit move...

Stacking pattern and stratigraphic model of reservoirs from a modern analogue to ancient deltaic and siliciclastic deposits: Golfe du Lion, SE France

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tesson, M.; Bernard, G.; Georges, A.

1995-08-01

The {open_quotes}Golfe du Lion{close_quotes} Pleistocene shelf deposits are used as modern analogues of ancient deltaic and shallow water siliciclastic deposits. At least 6 cyclic superimposed sedimentary packages constituting a seaward thickening wedge are documented, including major progradational clinoforms units bounded by regional unconformities, with their updip terminations. Seismic correlations and geometry models, together with age dating and facies analysis of the uppermost units have been used at regional scale. They allowed to differentiate allocyclic from autocyclic events, to improve our knowledge of the nature of tectonic control on architecture, and to rely the different seismic units, inside the packages, tomore » the environmental changes from interglacial highstand to glacial lowstand in 4 to 5th order cycles. An alternative model of {open_quotes}forced regression{close_quotes} during sea level lowstand was documented and validated. The different illustrated sedimentary units, related to specific parts of the relative sea level curve along a short duration/high amplitude cycle, are: (i) the {open_quotes}forced regression{close_quotes} deposits (ii) the late lowstand massive sands onto the outer shelf (iii) the early transgressive backstepping (?) beach sands, (iii) the late transgressive backslapping parasequences. The sand content inferred from the seismic facies, comforted with the uppermost units facies from data cores, is in agreement with this model.« less

Environmental Assessment for Beddown of Air Force Reserve Command Classic Associate Unit on A/OA-10 Operations and Maintenance Moody Air Force Base, Georgia

DTIC Science & Technology

2008-09-01

Code of Federal Regulations CO carbon monoxide CSAF Chief of Staff of the Air Force dB decibels DNL day-night average sound level DNLmr onset rate...the health and welfare of the general public. These seven pollutants (the “criteria pollutants”) include ozone, carbon monoxide (CO), nitrogen... Monoxide 9 ppm (10 mg/m3) 8-hour (1) None 35 ppm (40 mg/m3) 1-hour (1) None Lead 1.5 µg/m3 Quarterly Average Same as Primary Nitrogen Dioxide 0.053

The Temporary Environment - Cold Regions Habitability

DTIC Science & Technology

1976-10-01

studied: Arny. Air Force and FAA. Mobi/e hrduutei unkta Any industria ! unit that requires travel in the cold weather utilizes Army or civilian equipment ...vironmnts studied andc mecn in succeeding sctic.nis proceeds to a much fitter analysis . &nalyses start with prolic %,omparisuns of action patterns and...fornali/e cinviromnmienltal analysis below the le:vel ol’the behavior setting. l ie does specify smaller units such as cvosetties. syninnorphs. and

Variation within the "New Latino Diaspora": A Decade of Changes across the United States in the Equitable Participation of Latina/os in Higher Education

ERIC Educational Resources Information Center

Hatch, Deryl K.; Mardock Uman, Naomi; Garcia, Crystal E.

2016-01-01

This study problematizes the common discourse that rapid and widespread Latina/o demographic growth in the United States is a driving force in realizing higher education equity gains. Using equity indices for students, faculty, and administrative leaders at the state level, we present a portrait of changes in Latina/o participation in higher…

Optimization of Turkish Air Force SAR Units Forward Deployment Points for a Central Based SAR Force Structure

DTIC Science & Technology

2015-03-26

Turkish Airborne Early Warning and Control (AEW& C ) aircraft in the combat arena. He examines three combat scenarios Turkey might encounter to cover and...to limited SAR assets, constrained budgets, logistic- maintenance problems, and high risk level of military flights. In recent years, the Turkish Air...model, Set Covering Location Problem (SCLP), defines the minimum number of SAR DPs to cover all fighter aircraft training areas (TAs). The second

Joint Force Quarterly. Issue 70, 3rd Quarter, July 2013

DTIC Science & Technology

2013-07-01

such as solar panels and wind turbines for battlefield operations in Iraq. General Zilmer’s memo noted that without renewable power, U.S. forces...programs. The private sector may be leveraged through other incentives. Tax policy could encour- age the importation of solar panels, wind turbines , and...officers with infantry battalions—to name a few.31 In short, primary collection is done at the small unit level where there are “many sensors ,” and

A Future With The United States Air Force Advanced Maintenance And Munitions Operations School: Securing Strategic Agility Through 2036

DTIC Science & Technology

2016-06-01

SCIENCES Advisor: Dr. Paul J. Springer Maxwell Air Force Alabama August 2015 / June 2016 DISTRIBUTION A. Approved for public release...experienced rapid changes in the way the Service performs its roles to best complement our nation’s warfighting capability. Fueled by technology, innovation ...requires foresight and a level of organization and training that is ready to operate in environments which are heavily contested, degraded, and

Functional compartmentalization of the human superficial masseter muscle.

PubMed

Guzmán-Venegas, Rodrigo A; Biotti Picand, Jorge L; de la Rosa, Francisco J Berral

2015-01-01

Some muscles have demonstrated a differential recruitment of their motor units in relation to their location and the nature of the motor task performed; this involves functional compartmentalization. There is little evidence that demonstrates the presence of a compartmentalization of the superficial masseter muscle during biting. The aim of this study was to describe the topographic distribution of the activity of the superficial masseter (SM) muscle's motor units using high-density surface electromyography (EMGs) at different bite force levels. Twenty healthy natural dentate participants (men: 4; women: 16; age 20±2 years; mass: 60±12 kg, height: 163±7 cm) were selected from 316 volunteers and included in this study. Using a gnathodynamometer, bites from 20 to 100% maximum voluntary bite force (MVBF) were randomly requested. Using a two-dimensional grid (four columns, six electrodes) located on the dominant SM, EMGs in the anterior, middle-anterior, middle-posterior and posterior portions were simultaneously recorded. In bite ranges from 20 to 60% MVBF, the EMG activity was higher in the anterior than in the posterior portion (p-value = 0.001).The center of mass of the EMG activity was displaced towards the posterior part when bite force increased (p-value = 0.001). The topographic distribution of EMGs was more homogeneous at high levels of MVBF (p-value = 0.001). The results of this study show that the superficial masseter is organized into three functional compartments: an anterior, a middle and a posterior compartment. However, this compartmentalization is only seen at low levels of bite force (20-60% MVBF).

Functional Compartmentalization of the Human Superficial Masseter Muscle

PubMed Central

Guzmán-Venegas, Rodrigo A.; Biotti Picand, Jorge L.; de la Rosa, Francisco J. Berral

2015-01-01

Some muscles have demonstrated a differential recruitment of their motor units in relation to their location and the nature of the motor task performed; this involves functional compartmentalization. There is little evidence that demonstrates the presence of a compartmentalization of the superficial masseter muscle during biting. The aim of this study was to describe the topographic distribution of the activity of the superficial masseter (SM) muscle’s motor units using high-density surface electromyography (EMGs) at different bite force levels. Twenty healthy natural dentate participants (men: 4; women: 16; age 20±2 years; mass: 60±12 kg, height: 163±7 cm) were selected from 316 volunteers and included in this study. Using a gnathodynamometer, bites from 20 to 100% maximum voluntary bite force (MVBF) were randomly requested. Using a two-dimensional grid (four columns, six electrodes) located on the dominant SM, EMGs in the anterior, middle-anterior, middle-posterior and posterior portions were simultaneously recorded. In bite ranges from 20 to 60% MVBF, the EMG activity was higher in the anterior than in the posterior portion (p-value = 0.001).The center of mass of the EMG activity was displaced towards the posterior part when bite force increased (p-value = 0.001). The topographic distribution of EMGs was more homogeneous at high levels of MVBF (p-value = 0.001). The results of this study show that the superficial masseter is organized into three functional compartments: an anterior, a middle and a posterior compartment. However, this compartmentalization is only seen at low levels of bite force (20–60% MVBF). PMID:25692977

Theory of Near-Field Scanning with a Probe Array

DTIC Science & Technology

2014-01-01

AIR FORCE RESEARCH LABORATORY SENSORS DIRECTORATE WRIGHT-PATTERSON AIR FORCE BASE, OH 45433-7320 AIR FORCE MATERIEL COMMAND...AFRL/RYMH) Sensors Directorate, Air Force Research Laboratory Wright-Patterson Air Force Base, OH 45433-7320 Air Force Materiel Command, United...S) AND ADDRESS(ES) 10. SPONSORING/MONITORING AGENCY ACRONYM(S) Air Force Research Laboratory Sensors Directorate Wright-Patterson Air Force Base

A Constant-Force Resistive Exercise Unit

NASA Technical Reports Server (NTRS)

Colosky, Paul; Ruttley, Tara

2010-01-01

A constant-force resistive exercise unit (CFREU) has been invented for use in both normal gravitational and microgravitational environments. In comparison with a typical conventional exercise machine, this CFREU weighs less and is less bulky: Whereas weight plates and associated bulky supporting structures are used to generate resistive forces in typical conventional exercise machines, they are not used in this CFREU. Instead, resistive forces are generated in this CFREU by relatively compact, lightweight mechanisms based on constant-torque springs wound on drums. Each such mechanism is contained in a module, denoted a resistive pack, that includes a shaft for making a torque connection to a cable drum. During a stroke of resistive exercise, the cable is withdrawn from the cable drum against the torque exerted by the resistance pack. The CFREU includes a housing, within which can be mounted one or more resistive pack(s). The CFREU also includes mechanisms for engaging any combination of (1) one or more resistive pack(s) and (2) one or more spring(s) within each resistive pack to obtain a desired level of resistance.

Units

Science.gov Websites

Maxwell Air Force Base Maxwell Air Force Base Join the Air Force Home News AF News Commentaries Services SAPR FOIA Retiree Activities Office Centennial Search Maxwell Air Force Base: Home > Units Site

Superfund record of decision (EPA Region 9): Mather Air Force Base, Soil and Groundwater operable units, Sacramento, CA, June 21, 1996

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

The decision document presents the selected remedial actions for the Soil Operable Unit (OU) Sites and Groundwater OU Plumes, at the formerly active Mather Air Force Base (AFB), Sacramento County, California. The purpose of the Record of Decision (ROD) is to decide the appropriate level of remediation necessary to protect human health and the environment, and determine what requirements are applicable or relevant and appropriate requirements (ARARs) based on the groundwater beneficial use designation and site-specific conditions. The ROD has been divided into seven sections which specifically address the range of selected remedial actions for the Soil OU sites andmore » Groundwater OU plumes.« less

Training and Organization of the US Army Reserve Components; A Reference Text for Total Force Trainers, 1987-1988. (2d Edition)

DTIC Science & Technology

1988-04-04

year or small groups of units USATB 2 over several years, the nature of the time factor for RC units is as described above and the implications for...relocation of soldiers, but more often leave groups of soldiers where they are and convert them in place. This in-place conversion creates large scale MOS...they are not issued a new group of MOS qualified soldiers to start up the new organization. 6. The turbulence levels faced by RC units is significant

A Systems Architecture and Advanced Sensors Application for Real-Time Aircraft Structural Health Monitoring

DTIC Science & Technology

2011-03-01

DEPARTMENT OF THE AIR FORCE AIR UNIVERSITY AIR FORCE INSTITUTE OF TECHNOLOGY Wright-Patterson Air Force Base, Ohio APPROVED FOR PUBLIC RELEASE...position of the United States Air Force, Department of Defense, or the United States Government. This material is declared a work of the United...Management Graduate School of Engineering and Management Air Force Institute of Technology Air University Air Education and Training Command In

Effect of ageing on the force development in tetanic contractions of motor units in rat medial gastrocnemius muscle.

PubMed

Łochyński, Dawid; Kaczmarek, Dominik; Krutki, Piotr; Celichowski, Jan

2010-09-01

The purpose of this study was to determine the effect of ageing on the rate of force generation of motor units, and the mechanical efficiency of contraction produced by a doublet discharge. The study was carried out on isolated motor units of rat medial gastrocnemius muscle of young (5-10 mo) and two groups of old (24-25 and 28-30 mo) Wistar rats. Motor units were classified into the fast fatigable (FF), fast resistant (FR) and slow (S) ones. The force output and rate of force development were determined for non-doublet unfused tetanic contractions evoked by a series of a constant-rate trains of pulses and corresponding doublet contractions starting with an initial brief interpulse interval of 5 ms, and for maximal tetanic contraction. In FF motor units the rate of force development and the force produced by the doublet discharge increased transiently at the age of 24-25 mo, while in S and FR motor units this increase was observed at the age of 28-30 mo. Age-related decrease in the rate of force development of skeletal muscle cannot be attributed to a decline in efficiency of force production by functioning motor units. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Meeting the healthcare needs of transgender people within the armed forces: putting UK military policy into practice.

PubMed

Whybrow, Dean; New, Chris; Coetzee, Rik; Bickerstaffe, Paul

2016-12-01

To explain how the healthcare needs of transgender personnel are met within the United Kingdom Armed Forces. It may be that when transgender people disclose their gender preference that they are at increased risk of social exclusion. The United Kingdom Armed Forces has an inclusive organisational policy for the recruitment and management of transgender personnel. This is a position paper about how the healthcare needs of transgender military personnel are met by the United Kingdom Armed Forces. United Kingdom Armed Forces policy was placed into context by reviewing current research, discussing medical terminology and describing the policy. This was followed by an account of how UK AF policy is applied in practice. Where armed forces had an inclusive policy for the management of transgender personnel, there seemed to be little cause for secrecy and zero tolerance of discrimination when compared to nations where this was not the case. Medical terminology has changed to reflect a more inclusive, less stigmatising use of language. The United Kingdom Armed Forces policy has been described as progressive and inclusive. The application of this policy in practice may be dependent upon strong leadership and training. The wider United Kingdom Armed Forces seems capable of adopting a pragmatic and flexible approach to meeting the healthcare needs of transgender personnel. The United Kingdom Armed Forces value diversity within their workforce and have a progressive, inclusive policy for the recruitment and management of transgender personnel. When supporting a transgender military person, healthcare professionals, civilian organisations and military line managers should consider referring to United Kingdom Armed Forces policy as early as possible. Other military and uniformed services may wish to examine the United Kingdom Armed Forces exemplar in order to consider the applicability within their own organisational setting. © 2016 John Wiley & Sons Ltd.

Independence of motor unit recruitment and rate modulation during precision force control.

PubMed

Kamen, G; Du, D C

1999-01-01

The vertebrate motor system chiefly employs motor unit recruitment and rate coding to modulate muscle force output. In this paper, we studied how the recruitment of new motor units altered the firing rate of already-active motor units during precision force production in the first dorsal interosseous muscle. Six healthy adults performed linearly increasing isometric voluntary contractions while motor unit activity and force output were recorded. After motor unit discharges were identified, motor unit firing rates were calculated before and after the instances of new motor unit recruitment. Three procedures were applied to compute motor unit firing rate, including the mean of a fixed number of inter-spike intervals and the constant width weighted Hanning window filter method, as well as a modified boxcar technique. In contrast to previous reports, the analysis of the firing rates of over 200 motor units revealed that reduction of the active firing rates was not a common mechanism used to accommodate the twitch force produced by the recruitment of a new motor unit. Similarly, during de-recruitment there was no tendency for motor unit firing rates to increase immediately following the cessation of activity in other motor units. Considerable consistency in recruitment behavior was observed during repeated contractions. However, firing rates during repeated contractions demonstrated considerably more fluctuation. It is concluded that the neuromuscular system does not use short-term preferential motor unit disfacilitation to effect precise regulation of muscular force output.

PSE Aysis of Crossflow Instability on HifIre-5B Flight Test

DTIC Science & Technology

2017-06-05

AIR FORCE RESEARCH LABORATORY AEROSPACE SYSTEMS DIRECTORATE WRIGHT-PATTERSON AIR FORCE BASE, OH 45433-7542 AIR FORCE MATERIEL COMMAND UNITED...Air Force Research Laboratory, Aerospace Systems Directorate Wright-Patterson Air Force Base, OH 45433-7542 Air Force Materiel Command, United...States Air Force 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSORING/MONITORING Air Force Research Laboratory Aerospace Systems

Increases in human motoneuron excitability after cervical spinal cord injury depend on the level of injury.

PubMed

Thomas, Christine K; Häger, Charlotte K; Klein, Cliff S

2017-02-01

After human spinal cord injury (SCI), motoneuron recruitment and firing rate during voluntary and involuntary contractions may be altered by changes in motoneuron excitability. Our aim was to compare F waves in single thenar motor units paralyzed by cervical SCI to those in uninjured controls because at the single-unit level F waves primarily reflect the intrinsic properties of the motoneuron and its initial segment. With intraneural motor axon stimulation, F waves were evident in all 4 participants with C 4 -level SCI, absent in 8 with C 5 or C 6 injury, and present in 6 of 12 Uninjured participants (P < 0.001). The percentage of units that generated F waves differed across groups (C 4 : 30%, C 5 or C 6 : 0%, Uninjured: 16%; P < 0.001). Mean (±SD) proximal axon conduction velocity was slower after C 4 SCI [64 ± 4 m/s (n = 6 units), Uninjured: 73 ± 8 m/s (n = 7 units); P = 0.037]. Mean distal axon conduction velocity differed by group [C 4 : 40 ± 8 m/s (n = 20 units), C 5 or C 6 : 49 ± 9 m/s (n = 28), Uninjured: 60 ± 7 m/s (n = 45); P < 0.001]. Motor unit properties (EMG amplitude, twitch force) only differed after SCI (P ≤ 0.004), not by injury level. Motor units with F waves had distal conduction velocities, M-wave amplitudes, and twitch forces that spanned the respective group range, indicating that units with heterogeneous properties produced F waves. Recording unitary F waves has shown that thenar motoneurons closer to the SCI (C 5 or C 6 ) have reduced excitability whereas those further away (C 4 ) have increased excitability, which may exacerbate muscle spasms. This difference in motoneuron excitability may be related to the extent of membrane depolarization following SCI. Unitary F waves were common in paralyzed thenar muscles of people who had a chronic spinal cord injury (SCI) at the C 4 level compared with uninjured people, but F waves did not occur in people that had SCI at the C 5 or C 6 level. These results highlight that intrinsic motoneuron excitability depends, in part, on how close the motoneurons are to the site of the spinal injury, which could alter the generation and strength of voluntary and involuntary muscle contractions. Copyright © 2017 the American Physiological Society.

Task and fatigue effects on low-threshold motor units in human hand muscle.

PubMed

Enoka, R M; Robinson, G A; Kossev, A R

1989-12-01

1. The activity of single motor units was recorded in the first dorsal interosseus muscle of human subjects while they performed an isometric ramp-and-hold maneuver. Motor-unit activity was characterized before and after fatigue by the use of a branched bipolar electrode that was positioned subcutaneously over the test muscle. Activity was characterized in terms of the forces of recruitment and derecruitment and the discharge pattern. The purpose was to determine, before and after fatigue, whether motor-unit activity was affected by the direction in which the force was exerted. 2. Regardless of the task during prefatigue trials, interimpulse intervals were 1) more variable during increases or decreases in force than when force was held constant at the target value (4-6% above the recruitment force), and 2) more clustered around an arbitrary central value than would be expected with a normal (Gaussian) distribution. Both effects were seen during the flexion and abduction tasks. The behavior of low-threshold motor units in first dorsal interosseus is thus largely unaffected by the direction of the force exerted by the index finger. The absence of a task (i.e., a direction of force) effect suggests that the resultant force vector about the metacarpophalangeal joint of the index finger is not coded in terms of discrete populations of motor units, but, rather, it is based on the net muscle activity about the joint. 3. Motor-unit behavior during and after fatigue showed that the relatively homogeneous behavior seen before fatigue could be severely disrupted. The fatiguing protocol involved the continuous repetition, to the endurance limit, of a 15-s ramp-and-hold maneuver in which the abduction target force was 50% of maximum and was held for 10-s epochs (ramps up and down were approximately 2 s each). Motor-unit threshold was assessed by the forces of recruitment and derecruitment associated with each cycle of the fatigue test. Changes in recruitment force during the protocol were either minimal or, when present, not systematic. In contrast, the derecruitment force of all units exhibited a marked and progressive increase over the course of the test. 4. After the fatigue test, when the initial threshold tasks were repeated, the behavior of most motor units changed. These changes included the derecruitment of previously active motor units, the recruitment of additional motor units, and an increased discharge variability of units that remained recruited. The variation in recruitment order seemed to be much greater than that reported previously for nonfatiguing conditions.(ABSTRACT TRUNCATED AT 400 WORDS)

Improving US theater nuclear doctrine. a critical analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sollinger, J.M.

This monograph argues that the doctrine, equipment, and training of US forces do not meet the demands of fighting a theater nuclear war. Current doctrine rests upon questionable assumptions, lacks the flexibility required to fight a tactical nuclear battle, and limits itself by concentrating on defense. Recommended improvements include increased flexibility and decentralized execution, emphasizing maneuver and dispersion. Service doctrinal writings should focus on enemy forces rather than terrain. Because the nuclear battlefield promises chaos and confusion, US forces need redundant command and control. The equipment of US forces also needs improving, The services must field equipment capable of withstandingmore » the effects of nuclear weapons. In most cases this requirement means making existing procedures work and the hardening of equipment. Some new items of equipment, such as monitoring devices, are needed. Training requires improvement at both the individual and unit levels. Individual enlisted training tends to concentrate specialized knowledge at too high a level. With substantial casualties expected in a nuclear battle, US forces cannot afford to confine specialized knowledge to a few individuals.« less

United States Air Force High School Apprenticeship Program: 1989 Program Management Report. Volume 3

DTIC Science & Technology

1988-12-01

orrtent of visual or auditory stimulus exposed to the eyes o- oays -t a level below normal threshold, it is possible to perceive the subliminal stimuli...usually to small or vague to be consciously recognized, but they are declared to influence the 87-6 viewer’s subconsc’ious sex drive. Stimulation below...programs the mechanisms to stimulate career interests in science and technology in high school students showing promise in these areas. The Air Force High

Comparison of 20-, 23-, and 25-gauge air infusion forces.

PubMed

Machado, Leonardo Martins; Magalhães, Octaviano; Maia, Mauricio; Rodrigues, Eduardo B; Farah, Michel Eid; Ismail, Kamal A R; Molon, Leandro; Oliveira, Danilo A

2011-11-01

To determine and compare 20-, 23-, and 25-gauge retinal infusion air jet impact pressure (force per unit area) in an experimental setting. Experimental laboratory investigation. Infusion cannulas were connected to a compressed air system. A controlled valve mechanism was used to obtain increasing levels of infusion pressure. Each infusion tube was positioned in front of a manual transducer to measure force. Impact pressure was calculated using known formulas in fluid dynamics. The 20-gauge infusion jet showed similar impact pressure values compared with the 23-gauge infusion jet. Both showed higher levels than the 25-gauge infusion jet. This was because of the smaller jet force for the 25-gauge system. In this experimental study, both the 23- and the 20-gauge air infusion jet showed higher impact pressure values compared with the 25-gauge air infusion jet. This could be of concern regarding air infusion during 23-gauge vitrectomy since retinal damage has been shown in standard-gauge surgeries.

Factors Influencing Learner Conceptions of Force: Exploring the Interaction among Visuospatial Ability, Motivation, and Conceptions of Newtonian Mechanics in University Undergraduates from an Evolutionary Perspective

NASA Astrophysics Data System (ADS)

Vallett, David Bruce

This study examined the relationships among visuospatial ability, motivation to learn science, and learner conceptions of force across commonly measured demographics with university undergraduates with the aim of examining the support for an evolved sense of force and motion. Demographic variables of interest included age, ethnicity, and gender, which served to determine the ubiquity of the effects of the exogenous variables. Participants (n=91) self selected from introductory physics courses at a large public university in the Mid-Atlantic region of the United States. Utilizing a single-group exploratory design, all participants completed a series of anonymous online instruments to assess the variables of interest. Analysis consisted of an ANOVA for significance testing of demographic variables and a single-level structural equation model (SEM) to ascertain the causal influence of visuospatial ability and affect in the form of motivation on learner conceptions of force. Results of the SEM indicated that while motivation had a nonsignificant (p>.05) impact with this sample, visuospatial ability had a strong (.5 unit change in physics achievement per unit of VSA, p<.05) influence on Newtonian conceptions of mechanics. The results of this study inform physics educators as to the factors underlying conceptual change in Newtonian physics and generate hypotheses regarding the cognitive processes and corresponding neural substrates associated with successful Newtonian reasoning.

The challenge of an aging work force: keeping older workers employed and employable.

PubMed

Rix, S E

1996-01-01

This article reviews labor-force trends and older-worker employment policies in Japan and the United States. Both countries have aging work forces, but Japan's labor force is and for some time has been older than that of the United States. Japan's Ministry of Labor began addressing older-worker issues over 30 years ago and in the ensuing years has promulgated numerous initiatives to extend working life. Mandatory retirement, however, remains both legal and common in Japan, yet labor-force participation rates are higher for older persons in that country than in the United States, where mandatory retirement is illegal. Japan's older-worker programs and policies clearly seem to have an impact on labor-force rates, although those rates are dropping among the elderly in Japan as well as in the United States. The transferability of these programs and policies to the United States is discussed.

Environmental Assessment, Balloon Launch and Landing Operations, Air Force Research Laboratory, Space Vehicles Directorate, Kirtland Air Force Base, New Mexico

DTIC Science & Technology

2012-06-01

Force Research Laboratory , Space Vehicles Directorate ( AFRL /RV) located at Kirtland Air Force Base is preparing an Environmental Assessment (EA) for...United States Air Force Research Laboratory , Space Vehicles Directorate ( AFRL /RV) located at Kirtland Air Force Base is preparing an Environmental...United States Air Force Research Laboratory , Space Vehicles Directorate ( AFRL

reaxFF Reactive Force Field for Disulfide Mechanochemistry, Fitted to Multireference ab Initio Data.

PubMed

Müller, Julian; Hartke, Bernd

2016-08-09

Mechanochemistry, in particular in the form of single-molecule atomic force microscopy experiments, is difficult to model theoretically, for two reasons: Covalent bond breaking is not captured accurately by single-determinant, single-reference quantum chemistry methods, and experimental times of milliseconds or longer are hard to simulate with any approach. Reactive force fields have the potential to alleviate both problems, as demonstrated in this work: Using nondeterministic global parameter optimization by evolutionary algorithms, we have fitted a reaxFF force field to high-level multireference ab initio data for disulfides. The resulting force field can be used to reliably model large, multifunctional mechanochemistry units with disulfide bonds as designed breaking points. Explorative calculations show that a significant part of the time scale gap between AFM experiments and dynamical simulations can be bridged with this approach.

Meeting the Challenge of Mathematics Reform for Students with LD.

ERIC Educational Resources Information Center

Woodward, John; Montague, Marjorie

2002-01-01

This article discusses forces driving mathematics reform: shifting theoretical paradigms, disappointing levels of mathematics performance of students in the United States, and the impact of rapidly changing technologies. Concerns about this reform from the special education community are discussed, and synthesized special education research…

Unity of Effort: Delineating Responsibility for Reconstruction and Stability Operations at the National Level

DTIC Science & Technology

2010-06-11

International Labour Organisation Office for the Coordination of Humanitarian Affairs Peacebuilding Support Office United Kingdom Cabinet Office... absentees numbered in the tens of thousands (GAO 2005b, 7). Additionally, the total number of forces is misleading because both the trained

A phenomenological model that predicts forces generated when electrical stimulation is superimposed on submaximal volitional contractions

PubMed Central

Perumal, Ramu; Wexler, Anthony S.; Kesar, Trisha M.; Jancosko, Angela; Laufer, Yocheved

2010-01-01

Superimposition of electrical stimulation during voluntary contractions is used to produce functional movements in individuals with central nervous system impairment, to evaluate the ability to activate a muscle, to characterize the nature of fatigue, and to improve muscle strength during postsurgical rehabilitation. Currently, the manner in which voluntary contractions and electrically elicited forces summate is not well understood. The objective of the present study is to develop a model that predicts the forces obtained when electrical stimulation is superimposed on a volitional contraction. Quadriceps femoris muscles of 12 able-bodied subjects were tested. Our results showed that the total force produced when electrical stimulation was superimposed during a volitional contraction could be modeled by the equation T = V + S[(MaxForce − V)/MaxForce]N, where T is the total force produced, V is the force in response to volitional contraction alone, S is the force response to the electrical stimulation alone, MaxForce is the maximum force-generating ability of the muscle, and N is a parameter that we posit depends on the differences in the motor unit recruitment order and firing rates between volitional and electrically elicited contractions. In addition, our results showed that the model predicted accurately (intraclass correlation coefficient ≥0.97) the total force in response to a wide range of stimulation intensities and frequencies superimposed on a wide range of volitional contraction levels. Thus the model will be helpful to clinicians and scientists to predict the amount of stimulation needed to produce the targeted force levels in individuals with partial paralysis. PMID:20299613

Speed, Acceleration, and Velocity: Level II, Unit 9, Lesson 1; Force, Mass, and Distance: Lesson 2; Types of Motion and Rest: Lesson 3; Electricity and Magnetism: Lesson 4; Electrical, Magnetic, and Gravitational Fields: Lesson 5; The Conservation and Conversion of Matter and Energy: Lesson 6; Simple Machines and Work: Lesson 7; Gas Laws: Lesson 8; Principles of Heat Engines: Lesson 9; Sound and Sound Waves: Lesson 10; Light Waves and Particles: Lesson 11; Program. A High.....

ERIC Educational Resources Information Center

Manpower Administration (DOL), Washington, DC. Job Corps.

This self-study program for high-school level contains lessons on: Speed, Acceleration, and Velocity; Force, Mass, and Distance; Types of Motion and Rest; Electricity and Magnetism; Electrical, Magnetic, and Gravitational Fields; The Conservation and Conversion of Matter and Energy; Simple Machines and Work; Gas Laws; Principles of Heat Engines;…

Accelerated Molecular Dynamics Simulations with the AMOEBA Polarizable Force Field on Graphics Processing Units

PubMed Central

2013-01-01

The accelerated molecular dynamics (aMD) method has recently been shown to enhance the sampling of biomolecules in molecular dynamics (MD) simulations, often by several orders of magnitude. Here, we describe an implementation of the aMD method for the OpenMM application layer that takes full advantage of graphics processing units (GPUs) computing. The aMD method is shown to work in combination with the AMOEBA polarizable force field (AMOEBA-aMD), allowing the simulation of long time-scale events with a polarizable force field. Benchmarks are provided to show that the AMOEBA-aMD method is efficiently implemented and produces accurate results in its standard parametrization. For the BPTI protein, we demonstrate that the protein structure described with AMOEBA remains stable even on the extended time scales accessed at high levels of accelerations. For the DNA repair metalloenzyme endonuclease IV, we show that the use of the AMOEBA force field is a significant improvement over fixed charged models for describing the enzyme active-site. The new AMOEBA-aMD method is publicly available (http://wiki.simtk.org/openmm/VirtualRepository) and promises to be interesting for studying complex systems that can benefit from both the use of a polarizable force field and enhanced sampling. PMID:24634618

Use of a tibial accelerometer to measure ground reaction force in running: A reliability and validity comparison with force plates.

PubMed

Raper, Damian P; Witchalls, Jeremy; Philips, Elissa J; Knight, Emma; Drew, Michael K; Waddington, Gordon

2018-01-01

The use of microsensor technologies to conduct research and implement interventions in sports and exercise medicine has increased recently. The objective of this paper was to determine the validity and reliability of the ViPerform as a measure of load compared to vertical ground reaction force (GRF) as measured by force plates. Absolute reliability assessment, with concurrent validity. 10 professional triathletes ran 10 trials over force plates with the ViPerform mounted on the mid portion of the medial tibia. Calculated vertical ground reaction force data from the ViPerform was matched to the same stride on the force plate. Bland-Altman (BA) plot of comparative measure of agreement was used to assess the relationship between the calculated load from the accelerometer and the force plates. Reliability was calculated by intra-class correlation coefficients (ICC) with 95% confidence intervals. BA plot indicates minimal agreement between the measures derived from the force plate and ViPerform, with variation at an individual participant plot level. Reliability was excellent (ICC=0.877; 95% CI=0.825-0.917) in calculating the same vertical GRF in a repeated trial. Standard error of measure (SEM) equalled 99.83 units (95% CI=82.10-119.09), which, in turn, gave a minimum detectable change (MDC) value of 276.72 units (95% CI=227.32-330.07). The ViPerform does not calculate absolute values of vertical GRF similar to those measured by a force plate. It does provide a valid and reliable calculation of an athlete's lower limb load at constant velocity. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Discharge characteristics of biceps brachii motor units at recruitment when older adults sustained an isometric contraction.

PubMed

Pascoe, Michael A; Holmes, Matthew R; Enoka, Roger M

2011-02-01

The purpose of this study was to compare the discharge characteristics of motor units recruited during an isometric contraction that was sustained with the elbow flexor muscles by older adults at target forces that were less than the recruitment threshold force of each isolated motor unit. The discharge times of 27 single motor units were recorded from the biceps brachii in 11 old adults (78.8 ± 5.9 yr). The target force was set at either a relatively small (6.6 ± 3.7% maximum) or large (11.4 ± 4.5% maximum) difference below the recruitment threshold force and the contraction was sustained until the motor unit was recruited and discharged action potentials for about 60 s. The time to recruitment was longer for the large target-force difference (P = 0.001). At recruitment, the motor units discharged repetitively for both target-force differences, which contrasts with data from young adults when motor units discharged intermittently at recruitment for the large difference between recruitment threshold force and target force. The coefficient of variation (CV) for the first five interspike intervals (ISIs) increased from the small (18.7 ± 7.9) to large difference (35.0 ± 10.2%, P = 0.008) for the young adults, but did not differ for the two target force differences for the old adults (26.3 ± 14.7 to 24.0 ± 13.1%, P = 0.610). When analyzed across the discharge duration, the average CV for the ISI decreased similarly for the two target-force differences (P = 0.618) in old adults. These findings contrast with those of young adults and indicate that the integration of synaptic input during sustained contractions differs between young and old adults.

Optimized coordination of brakes and active steering for a 4WS passenger car.

PubMed

Tavasoli, Ali; Naraghi, Mahyar; Shakeri, Heman

2012-09-01

Optimum coordination of individual brakes and front/rear steering subsystems is presented. The integrated control strategy consists of three modules. A coordinated high-level control determines the body forces/moment required to achieve vehicle motion objectives. The body forces/moment are allocated to braking and steering subsystems through an intermediate unit, which integrates available subsystems based on phase plane notion in an optimal manner. To this end, an optimization problem including several equality and inequality constraints is defined and solved analytically, such that a real-time implementation can be realized without the use of numeric optimization software. A low-level slip-ratio controller works to generate the desired longitudinal forces at small longitudinal slip-ratios, while averting wheel locking at large slip-ratios. The efficiency of the suggested approach is demonstrated through computer simulations. Copyright © 2012 ISA. Published by Elsevier Ltd. All rights reserved.

National Task Force on a Uniform Measurement Unit for the Recognition of Continuing Education: Working Papers; and The Continuing Education Unit: A Uniform Unit of Measure for Non-Credit Continuing Education Programs (An Interim Statement of the National Task Force).

ERIC Educational Resources Information Center

National Univ. Extension Association, Washington, DC.

In 1968, a national planning conference, under the joint sponsorship of 34 organizations responsing to continuing education needs, created the National Task Force to determine the feasibility of a uniform unit of measurement and develop a proposal for field testing the concept. Stressing that continuing education units should supplement, not…

Income inequality in today’s China

PubMed Central

Xie, Yu; Zhou, Xiang

2014-01-01

Using multiple data sources, we establish that China's income inequality since 2005 has reached very high levels, with the Gini coefficient in the range of 0.53–0.55. Analyzing comparable survey data collected in 2010 in China and the United States, we examine social determinants that help explain China’s high income inequality. Our results indicate that a substantial part of China’s high income inequality is due to regional disparities and the rural-urban gap. The contributions of these two structural forces are particularly strong in China, but they play a negligible role in generating the overall income inequality in the United States, where individual-level and family-level income determinants, such as family structure and race/ethnicity, play a much larger role. PMID:24778237

Income inequality in today's China.

PubMed

Xie, Yu; Zhou, Xiang

2014-05-13

Using multiple data sources, we establish that China's income inequality since 2005 has reached very high levels, with the Gini coefficient in the range of 0.53-0.55. Analyzing comparable survey data collected in 2010 in China and the United States, we examine social determinants that help explain China's high income inequality. Our results indicate that a substantial part of China's high income inequality is due to regional disparities and the rural-urban gap. The contributions of these two structural forces are particularly strong in China, but they play a negligible role in generating the overall income inequality in the United States, where individual-level and family-level income determinants, such as family structure and race/ethnicity, play a much larger role.

Rapid Response in the Homeland

DTIC Science & Technology

2009-12-11

SNG State National Guard USNG United States National Guard USNORTHCOM US Northern Command WMD Weapons of Mass Destruction WMD-CST Weapons of Mass...Guard exists simultaneously as two forces, the National Guard of the United States (USNG) and the state National Guard ( SNG ). The USNG is a reserve...9 military force composed of SNG militia members and is a joint reserve component of the United States Army and the United States Air Force. The

32 CFR 65.3 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

...-called `A' School). (3) In the case of members of the Air Force, Basic Military Training and Technical..., U.S.C. Entry Level and Skill Training. (1) In the case of members of the Army, Basic Combat Training and Advanced Individual Training, which includes members attending One Station Unit Training (OSUT...

Peer Effects in Academic Cheating

ERIC Educational Resources Information Center

Carrell, Scott E.; Malmstrom, Frederick V.; West, James E.

2008-01-01

Using self-reported academic cheating from the classes of 1959 through 2002 at the three major United States military service academies (Air Force, Army, and Navy), we measure how peer cheating influences individual cheating behavior. We find higher levels of peer cheating result in a substantially increased probability that an individual will…

Guidelines for Comprehensive Sexuality Education: Kindergarten-12th Grade.

ERIC Educational Resources Information Center

Sex Information and Education Council of the United States, Inc., New York, NY.

The National Guidelines for Comprehensive Sexuality Education were developed by a Sex Information and Education Council of the United States (SIECUS) task force made up of health, education, and sex education professionals. The group was tasked with formulating sex education concepts and guidelines within four developmental levels, from…

Preventing a Hollow Army: 20th Century Lessons for the 21st Century

DTIC Science & Technology

2012-06-08

Watergate scandal additionally provided challenges for the United States government as the nation reduced forces in Vietnam and looked to downsize the...levels and test scores among recruits, recruiting scandals to achieve required minimums in addition to an increase in bad discharges and peacetime

Correspondence Study; A Summary Review of the Research and Development Literature.

ERIC Educational Resources Information Center

Mathieson, David E.

Beginning with a historical review of private correspondence schools, supervised high school level programs, military programs (notable the United States Armed Forces Institute), and activities by such university extension luminaries as William Rainey Harper and W. H. Lighty, this literature review covers accreditation and licensing problems,…

26 CFR 1.692-1 - Abatement of income taxes of certain members of the Armed Forces of the United States upon death.

Code of Federal Regulations, 2011 CFR

2011-04-01

... the Armed Forces of the United States upon death. 1.692-1 Section 1.692-1 Internal Revenue INTERNAL...) Income in Respect of Decedents § 1.692-1 Abatement of income taxes of certain members of the Armed Forces... active service as a member of the Armed Forces of the United States, and (ii) His death occurs while he...

26 CFR 1.692-1 - Abatement of income taxes of certain members of the Armed Forces of the United States upon death.

Code of Federal Regulations, 2010 CFR

2010-04-01

... the Armed Forces of the United States upon death. 1.692-1 Section 1.692-1 Internal Revenue INTERNAL... Respect of Decedents § 1.692-1 Abatement of income taxes of certain members of the Armed Forces of the... as a member of the Armed Forces of the United States, and (ii) His death occurs while he is serving...

26 CFR 1.501(c)(19)-1 - War veterans organizations.

Code of Federal Regulations, 2011 CFR

2011-04-01

... persons, whether or not present members of the United States Armed Forces, who have served in the Armed Forces of the United States during a period of war (including the Korean and Vietnam conflicts). (2) The... members of the United States Armed Forces, (iii) Cadets (including only students in college or university...

26 CFR 1.501(c)(19)-1 - War veterans organizations.

Code of Federal Regulations, 2010 CFR

2010-04-01

... persons, whether or not present members of the United States Armed Forces, who have served in the Armed Forces of the United States during a period of war (including the Korean and Vietnam conflicts). (2) The... members of the United States Armed Forces, (iii) Cadets (including only students in college or university...

Panel Discussion: Near Real Time Imagery Intelligence How Will We Do It?

NASA Astrophysics Data System (ADS)

Andraitis, Arthur A.; Crane, Alfred C.; Daniels, George; Graham, Johnny; LaGesse, Francis R.

1987-02-01

This afternoon's panel discussion will address near real time imagery and intelligence--how will we do it? Our moderator is Arthur Andraitis, a consultant in intelligence reconnaissance systems and international marketing. He was commissioned in the United States Air Force out of the University of Idaho, and entered the Air Force in 1955 where he became an Image Intelligence Officer serving in a variety of intelligence and reconnaisance related assignments, including two tours each in Asia and Europe supporting tactical theater and national level operations. He also suffered through two Pentagon tours--one as Branch Chief of the Imagery Branch for the Assistant Chief of Staff for Intelligence. He was the U. S. National Coordinator for two NATO intelligence and reconnaissance panels, and served several assignments in support of special operations, which included a year with the special forces in Viet Nam where he flew many missions in L-19s, 01 and assault helicopters. He has been an advisor on intelligence and reconnaissance matters to several foreign countries. In 1978 he retired from the United States Air Force, went to work for Itek, and then became an independent consultant in intelligence and reconaissance systems. I would like to introduce Art Andraitis.

Localised task-dependent motor-unit recruitment in the masseter.

PubMed

Schindler, H J; Hellmann, D; Giannakopoulos, N N; Eiglsperger, U; van Dijk, J P; Lapatki, B G

2014-07-01

Localised motor-unit (MU) recruitment in the masseter was analysed in this study. We investigated whether differential activation behaviour, which has already been reported for distant masseter regions, can also be detected in small muscle subvolumes at the level of single MUs. Two bipolar fine-wire electrodes and an intra-oral 3D bite-force transmitter were used to record intra-muscular electromyograms (EMG) resulting from controlled bite-forces of 10 healthy human subjects (mean age 24.1 ± 1.2 years). Two-hundred and seventeen decomposed MUs were organised into localised MU task groups with different (P < 0.001) force-direction-specific behaviour. Proportions of MUs involved in one, two, three or four examined tasks were 46%, 31%, 18% and 5%, respectively. This study provides evidence of the ability of the neuromuscular system to modify the mechanical output of small masseter subvolumes by differential control of adjacent MUs belonging to distinct task groups. Localised differential activation behaviour of the masseter may be the crucial factor enabling highly flexible and efficient adjustment of the muscle activity in response to complex local biomechanical needs, for example, continually varying bite-forces during the demanding masticatory process. © 2014 John Wiley & Sons Ltd.

Assessing altered motor unit recruitment patterns in paretic muscles of stroke survivors using surface electromyography.

PubMed

Hu, Xiaogang; Suresh, Aneesha K; Rymer, William Z; Suresh, Nina L

2015-12-01

The advancement of surface electromyogram (sEMG) recording and signal processing techniques has allowed us to characterize the recruitment properties of a substantial population of motor units (MUs) non-invasively. Here we seek to determine whether MU recruitment properties are modified in paretic muscles of hemispheric stroke survivors. Using an advanced EMG sensor array, we recorded sEMG during isometric contractions of the first dorsal interosseous muscle over a range of contraction levels, from 20% to 60% of maximum, in both paretic and contralateral muscles of stroke survivors. Using MU decomposition techniques, MU action potential amplitudes and recruitment thresholds were derived for simultaneously activated MUs in each isometric contraction. Our results show a significant disruption of recruitment organization in paretic muscles, in that the size principle describing recruitment rank order was materially distorted. MUs were recruited over a very narrow force range with increasing force output, generating a strong clustering effect, when referenced to recruitment force magnitude. Such disturbances in MU properties also correlated well with the impairment of voluntary force generation. Our findings provide direct evidence regarding MU recruitment modifications in paretic muscles of stroke survivors, and suggest that these modifications may contribute to weakness for voluntary contractions.

Respiration-related discharge of hyoglossus muscle motor units in the rat.

PubMed

Powell, Gregory L; Rice, Amber; Bennett-Cross, Seres J; Fregosi, Ralph F

2014-01-01

Although respiratory muscle motor units have been studied during natural breathing, simultaneous measures of muscle force have never been obtained. Tongue retractor muscles, such as the hyoglossus (HG), play an important role in swallowing, licking, chewing, breathing, and, in humans, speech. The HG is phasically recruited during the inspiratory phase of the respiratory cycle. Moreover, in urethane anesthetized rats the drive to the HG waxes and wanes spontaneously, providing a unique opportunity to study motor unit firing patterns as the muscle is driven naturally by the central pattern generator for breathing. We recorded tongue retraction force, the whole HG muscle EMG and the activity of 38 HG motor units in spontaneously breathing anesthetized rats under low-force and high-force conditions. Activity in all cases was confined to the inspiratory phase of the respiratory cycle. Changes in the EMG were correlated significantly with corresponding changes in force, with the change in EMG able to predict 53-68% of the force variation. Mean and peak motor unit firing rates were greater under high-force conditions, although the magnitude of discharge rate modulation varied widely across the population. Changes in mean and peak firing rates were significantly correlated with the corresponding changes in force, but the correlations were weak (r(2) = 0.27 and 0.25, respectively). These data indicate that, during spontaneous breathing, recruitment of HG motor units plays a critical role in the control of muscle force, with firing rate modulation playing an important but lesser role.

Accurate physical laws can permit new standard units: The two laws F→=ma→ and the proportionality of weight to mass

NASA Astrophysics Data System (ADS)

Saslow, Wayne M.

2014-04-01

Three common approaches to F→=ma→ are: (1) as an exactly true definition of force F→ in terms of measured inertial mass m and measured acceleration a→; (2) as an exactly true axiom relating measured values of a→, F→ and m; and (3) as an imperfect but accurately true physical law relating measured a→ to measured F→, with m an experimentally determined, matter-dependent constant, in the spirit of the resistance R in Ohm's law. In the third case, the natural units are those of a→ and F→, where a→ is normally specified using distance and time as standard units, and F→ from a spring scale as a standard unit; thus mass units are derived from force, distance, and time units such as newtons, meters, and seconds. The present work develops the third approach when one includes a second physical law (again, imperfect but accurate)—that balance-scale weight W is proportional to m—and the fact that balance-scale measurements of relative weight are more accurate than those of absolute force. When distance and time also are more accurately measurable than absolute force, this second physical law permits a shift to standards of mass, distance, and time units, such as kilograms, meters, and seconds, with the unit of force—the newton—a derived unit. However, were force and distance more accurately measurable than time (e.g., time measured with an hourglass), this second physical law would permit a shift to standards of force, mass, and distance units such as newtons, kilograms, and meters, with the unit of time—the second—a derived unit. Therefore, the choice of the most accurate standard units depends both on what is most accurately measurable and on the accuracy of physical law.

Perspective on Out & Equal Workplace Advocates Building Bridges Model: A Retrospect of the Past, Present, and Future of Training Impacting Lesbian, Gay, Bisexual, and Transgender Employees in the Workplace

ERIC Educational Resources Information Center

Baillie, Pat; Gedro, Julie

2009-01-01

As early as 1983, a group of lesbian, gay, bisexual, and transgenders (LGBTs) in the San Francisco Bay Area met with the United Way to discuss the needs of the community in the workplace. In 1986, the United Way authorized a board-level task force on LGBT issues, which looked at health and human care concerns. In 1990, Building Bridges was formed…

Logistically Sustaining Afloat-Staged Special Operations Forces through an LPD-17 Class Single-Ship Seabase

DTIC Science & Technology

2007-03-01

simulation are analyzed using regression, statistical and marginal benefit techniques to show how the MOEs are affected by varying levels of the...being supported by the seabase increases. A large marginal benefit is realized in reducing a unit’s frequency and time spent in a balk state by...units. SOF units operate within the range of sea-based helicopter assets; therefore the risk of a ‘ bingo ’ (i.e., near empty) fuel state is nearly

19 CFR 148.90 - Foreign military personnel.

Code of Federal Regulations, 2011 CFR

2011-04-01

... baggage and effects of persons on duty in the United States as members of the armed forces of any foreign... member of the armed forces of any foreign country on duty in the United States, for his personal use or... consumption for the official use of members of the armed forces of any foreign country on duty in the United...

19 CFR 148.90 - Foreign military personnel.

Code of Federal Regulations, 2010 CFR

2010-04-01

... baggage and effects of persons on duty in the United States as members of the armed forces of any foreign... member of the armed forces of any foreign country on duty in the United States, for his personal use or... consumption for the official use of members of the armed forces of any foreign country on duty in the United...

A Heuristic FORTRAN Model of the Identification and Allocation of CONUS (Continental United States) Prime BEEF (Base Engineer Emergency Forces) Forces in Support of Theater OPlan (Operation Plan) Requirements.

DTIC Science & Technology

1983-09-01

and status systems (Albanese, 1981; Griffin, 1982; Lott & Lott, 1971). Group cohesiveness and norms, according to Wallace and Szilagyi (1982), were the... Wallace & Szilagyi , 1982): 1. The major difference between high and low cohesive groups would be how closely members conform to group norms ; and 2. Group...performance would be influenced not only by cohesiveness, but also by the level or strength of group norms. Research by Wallace and Szilagyi (1982

Environmental Assessment: BRAC Construction and Operation of Armed Forces Reserve Center at Malmstrom Air Force Base, Great Falls, Montana

DTIC Science & Technology

2009-06-01

Day-Night Levels in Urban Areas in the United States .................................4-31 4-5 Typical Construction Equipment and Composite Site...ramp 2 Reefer 4 1.5-ton Trailer 1 2.5-ton Trailer 1 5-ton Trailer 4 Mobile Kitchen Trailer 1 4-kilovolt (kV) Generator sets 3 10-kV generator...encountered in urban areas of the U.S. In general, 30 to 50 dB represents a quiet classification, 65 to 70 dB represents a moderately noisy

KSC-2015-1248

NASA Image and Video Library

2015-01-29

VANDENBERG AIR FORCE BASE, Calif. – The mobile service tower rolls toward the United Launch Alliance Delta II rocket at Space Launch Complex 2 on Vandenberg Air Force Base in California. Aboard the rocket is NOAA's Soil Moisture Active Passive satellite, or SMAP, designed to produce the highest-resolution maps of soil moisture ever obtained from space. Launch was postponed today due to violation of upper-level wind shear constraints. Launch now is targeted for Jan. 31. To learn more about SMAP, visit http://www.nasa.gov/smap. Photo credit: NASA/Randy Beaudoin

KSC-2015-1245

NASA Image and Video Library

2015-01-29

VANDENBERG AIR FORCE BASE, Calif. – Operations are underway at Space Launch Complex 2 on Vandenberg Air Force Base in California to enclose the United Launch Alliance Delta II rocket in the launch gantry. Aboard the rocket is NOAA's Soil Moisture Active Passive satellite, or SMAP, designed to produce the highest-resolution maps of soil moisture ever obtained from space. Launch was postponed today due to violation of upper-level wind shear constraints. Launch now is targeted for Jan. 31. To learn more about SMAP, visit http://www.nasa.gov/smap. Photo credit: NASA/Randy Beaudoin

KSC-2015-1247

NASA Image and Video Library

2015-01-29

VANDENBERG AIR FORCE BASE, Calif. – The mobile service tower rolls toward the United Launch Alliance Delta II rocket at Space Launch Complex 2 on Vandenberg Air Force Base in California. Aboard the rocket is NOAA's Soil Moisture Active Passive satellite, or SMAP, designed to produce the highest-resolution maps of soil moisture ever obtained from space. Launch was postponed today due to violation of upper-level wind shear constraints. Launch now is targeted for Jan. 31. To learn more about SMAP, visit http://www.nasa.gov/smap. Photo credit: NASA/Randy Beaudoin

KSC-2015-1246

NASA Image and Video Library

2015-01-29

VANDENBERG AIR FORCE BASE, Calif. – Operations are underway at Space Launch Complex 2 on Vandenberg Air Force Base in California to enclose the United Launch Alliance Delta II rocket in the launch gantry. Aboard the rocket is NOAA's Soil Moisture Active Passive satellite, or SMAP, designed to produce the highest-resolution maps of soil moisture ever obtained from space. Launch was postponed today due to violation of upper-level wind shear constraints. Launch now is targeted for Jan. 31. To learn more about SMAP, visit http://www.nasa.gov/smap. Photo credit: NASA/Randy Beaudoin

Developing the Mid-Level Civilian Logistician: An Empirical Study of United States Air Force GS-12 to GM-13 Professional Development.

DTIC Science & Technology

1989-09-01

airimn : PME NUMBER OF APPLICABLE RESPONSES PROGRAMS S S~ 1quadron Off icer-S SchoolI. Ai~rCcr 1 .n College, Air War College: self-direct-d Table 11...8217 betweenr- thie number of e:;ist ~p ~msancre:.t7 lcg~stiian weak-nesses (r -. 8545 ) Inditc. r: lo:w pcoitlive correlation e:xists b_-etween thenubr...equivalent) c. Industrial College of the Armed Forces d. Defense Systems Management Course e. Air War College (or equivalent) f. Other (please specify) g

Jobs and the resource curse in the sun: The effects of oil production on female labor force participation in California counties from 1980-2010

NASA Astrophysics Data System (ADS)

Zavala, Gabriel

This study aims to evaluate the relationship between oil income and the female labor force participation rate in California for the years of 1980, 1990, 2000 and 2010 using panel linear regression models. This study also aims to visualize the spatial patterns of both variables in California through Hot Spot analysis at the county level for the same years. The regression found no sign of a relationship between oil income and female labor force participation rate but did find evidence of a positive relationship between two income control variables and the female labor force participation rate. The hot spot analysis also found that female labor force participation cold spots are not spatially correlated with oil production hot spots. These findings contribute new methodologies at a finer scale to the very nuanced discussion of the resource curse in the United States.

76 FR 30497 - Armed Forces Day, 2011

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-25

... Forces Day, 2011 By the President of the United States of America A Proclamation The Armed Forces of the... its people. From our earliest days as a fledgling republic, the United States has relied on the.... On Armed Forces Day, let us salute the Soldiers, Sailors, Airmen, Marines, and Coast Guardsmen who...

77 FR 64493 - Office of the Secretary of the Air Force Acceptance of Group Application Under Public Law 95-202...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-22

... DEPARTMENT OF DEFENSE Department of the Air Force Office of the Secretary of the Air Force... AGENCY: The United States Air Force, DOD. ACTION: Notice. SUMMARY: Under the provisions of Section 401... group should be considered active military service to the Armed Forces of the United States are...

Nonstationary Gravity Wave Forcing of the Stratospheric Zonal Mean Wind

NASA Technical Reports Server (NTRS)

Alexander, M. J.; Rosenlof, K. H.

1996-01-01

The role of gravity wave forcing in the zonal mean circulation of the stratosphere is discussed. Starting from some very simple assumptions about the momentum flux spectrum of nonstationary (non-zero phase speed) waves at forcing levels in the troposphere, a linear model is used to calculate wave propagation through climatological zonal mean winds at solstice seasons. As the wave amplitudes exceed their stable limits, a saturation criterion is imposed to account for nonlinear wave breakdown effects, and the resulting vertical gradient in the wave momentum flux is then used to estimate the mean flow forcing per unit mass. Evidence from global, assimilated data sets are used to constrain these forcing estimates. The results suggest the gravity-wave-driven force is accelerative (has the same sign as the mean wind) throughout most of the stratosphere above 20 km. The sense of the gravity wave forcing in the stratosphere is thus opposite to that in the mesosphere, where gravity wave drag is widely believed to play a principal role in decelerating the mesospheric jets. The forcing estimates are further compared to existing gravity wave parameterizations for the same climatological zonal mean conditions. Substantial disagreement is evident in the stratosphere, and we discuss the reasons for the disagreement. The results suggest limits on typical gravity wave amplitudes near source levels in the troposphere at solstice seasons. The gravity wave forcing in the stratosphere appears to have a substantial effect on lower stratospheric temperatures during southern hemisphere summer and thus may be relevant to climate.

Nursing unit teams matter: Impact of unit-level nurse practice environment, nurse work characteristics, and burnout on nurse reported job outcomes, and quality of care, and patient adverse events--a cross-sectional survey.

PubMed

Van Bogaert, Peter; Timmermans, Olaf; Weeks, Susan Mace; van Heusden, Danny; Wouters, Kristien; Franck, Erik

2014-08-01

To investigate the impact of nurse practice environment factors, nurse work characteristics, and burnout on nurse reported job outcomes, quality of care, and patient adverse events variables at the nursing unit level. Nurse practice environment studies show growing insights and knowledge about determining factors for nurse workforce stability, quality of care, and patient safety. Until now, international studies have primarily focused on variability at the hospital level; however, insights at the nursing unit level can reveal key factors in the nurse practice environment. A cross-sectional design with a survey. In a cross-sectional survey, a sample of 1108 nurses assigned to 96 nursing units completed a structured questionnaire composed of various validated instruments measuring nurse practice environment factors, nurse work characteristics, burnout, nurse reported job outcomes, quality of care, and patient adverse events. Associations between the variables were examined using multilevel modelling techniques. Various unit-level associations (simple models) were identified between nurse practice environment factors, nurse work characteristics, burnout dimensions, and nurse reported outcome variables. Multiple multilevel models showed various independent variables such as nursing management at the unit level, social capital, emotional exhaustion, and depersonalization as important predictors of nurse reported outcome variables such job satisfaction, turnover intentions, quality of care (at the unit, the last shift, and in the hospital within the last year), patient and family complaints, patient and family verbal abuse, patient falls, nosocomial infections, and medications errors. Results suggested a stable nurse work force, with the capability to achieve superior quality and patient safety outcomes, is associated with unit-level favourable perceptions of nurse work environment factors, workload, decision latitude, and social capital, as well low levels of burnout. Nurses, physicians, nursing leaders, and executives share responsibility to create an environment supportive of interdisciplinary team development. Copyright © 2013 Elsevier Ltd. All rights reserved.

United States Air Force in Southeast Asia 1965-1973. Aces and Aerial Victories

DTIC Science & Technology

1976-01-01

UNITED STATES IN SOUTHEAST ACES and AERIAL VICTORIES The United States Air Force in SoutheastAsia 1965*19?3 by R Frank Fuirefl William H...TYPE 3. DATES COVERED 00-00-1976 to 00-00-1976 4. TITLE AND SUBTITLE United States Air Force in Southeast Asia 1965-1973. Aces and Aerial... aces and aerial victories, 1965-1973. Includes index and glossary. 1. Vietnamese Conflict, 1961-1975-Aerial operations, American. 2. Viet- namese

United States Air Force 611th Air Support Group/Civil Engineering Squadron Elmendorf AFB, Alaska. Remedial investigation and feasibility study. Bullen Point Radar Installation, Alaska. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Karmi, S.

1996-03-18

The United States Air Force (Air Force) has prepared this Remedial investigation/Feasibility Study (RI/FS) report as part of the Installation Restoration Program (IRP) to present results of RI/FS activities at five sites at the Bullen Point radar installation. The IRP provides for investigating, quantifying, and remediating environmental contamination from past waste management activities at Air Force installations throughout the United States.

Evaluation of higher order statistics parameters for multi channel sEMG using different force levels.

PubMed

Naik, Ganesh R; Kumar, Dinesh K

2011-01-01

The electromyograpy (EMG) signal provides information about the performance of muscles and nerves. The shape of the muscle signal and motor unit action potential (MUAP) varies due to the movement of the position of the electrode or due to changes in contraction level. This research deals with evaluating the non-Gaussianity in Surface Electromyogram signal (sEMG) using higher order statistics (HOS) parameters. To achieve this, experiments were conducted for four different finger and wrist actions at different levels of Maximum Voluntary Contractions (MVCs). Our experimental analysis shows that at constant force and for non-fatiguing contractions, probability density functions (PDF) of sEMG signals were non-Gaussian. For lesser MVCs (below 30% of MVC) PDF measures tends to be Gaussian process. The above measures were verified by computing the Kurtosis values for different MVCs.

Reconciling species-level vs plastic responses of evergreen leaf structure to light gradients: shade leaves punch above their weight.

PubMed

Lusk, Christopher H; Onoda, Yusuke; Kooyman, Robert; Gutiérrez-Girón, Alba

2010-04-01

*When grown in a common light environment, the leaves of shade-tolerant evergreen trees have a larger leaf mass per unit area (LMA) than their light-demanding counterparts, associated with differences in lifespan. Yet plastic responses of LMA run counter to this pattern: shade leaves have smaller LMA than sun leaves, despite often living longer. *We measured LMA and cell wall content, and conducted punch and shear tests, on sun and shade leaves of 13 rainforest evergreens of differing shade tolerance, in order to understand adaptation vs plastic responses of leaf structure and biomechanics to shade. *Species shade tolerance and leaf mechanical properties correlated better with cell wall mass per unit area than with LMA. Growth light environment had less effect on leaf mechanics than on LMA: shade leaves had, on average, 40% lower LMA than sun leaves, but differences in work-to-shear, and especially force-to-punch, were smaller. This was associated with a slightly larger cell wall fraction in shade leaves. *The persistence of shade leaves might reflect unattractiveness to herbivores because they yield smaller benefits (cell contents per area) per unit fracture force than sun leaves. In forest trees, cell wall fraction and force-to-punch are more robust correlates of species light requirements than LMA.

75 FR 44281 - Public Land Order No. 7747; Partial Revocation, Juniper Butte Range; Idaho

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-28

... affects a 5-acre parcel of land reserved on behalf of the United States Air Force in Owyhee County, Idaho... INFORMATION: The land included in this revocation was withdrawn on behalf of the United States Air Force as..., designated as ND-8, was never used by the United States Air Force, and they have determined that the...

26 CFR 49.4253-4 - Exemption for servicemen in combat zone.

Code of Federal Regulations, 2010 CFR

2010-04-01

... originating at (Point of origin) within a combat zone from (Name) a member of the Armed Forces of the United... zone, as defined in section 112, from a member of the Armed Forces of the United States performing... which Armed Forces of the United States are or have engaged in combat, and only if it is performed on or...

An Expert System Solution for the Quantitative Condition Assessment of Electrical Distribution Systems in the United States Air Force

DTIC Science & Technology

1991-09-01

Distribution system ... ......... 4 2. Architechture of an Expert system .. .............. 66 vi List of Tables Table Page 1. Prototype Component Model...expert system to properly process work requests Ln civil engineering (8:23). Electric Power Research Institute (EPRI). EPRI is a private organization ...used (51) Training Level. The level of training shop technicians receive, and the resulting proficiency, are important in all organizations . Experts 1

Army Sustainment. Volume 44, Issue 2, March-April 2012

DTIC Science & Technology

2012-04-01

b.a. deGree in criMinal justice adMinistration froM con- cordia colleGe in MicHiGan. He is leVel iii certified in loGistics ManaGeMent and leVel ii...book and unit supply), plant maintenance, finance, and Defense Forces and Public Security (DFPS). Together, these modules provide enhanced...maintenance-related information for all assigned assets. The plant maintenance module provides users with equipment readiness and enhanced personnel

Personal Protective Measures Against Insects and Other Arthropods of Military Significance

DTIC Science & Technology

2009-10-01

responsibility, although it is also an important adjunct to unit- level and higher echelon preventive medicine countermeasures. Military personnel must be aware...fabric treatment level of 0.52% weight by weight of active ingredient. (d) Several steps are essential in properly using this treatment method...Control as a Force Multiplier. Defense 90. pp. 26-35. Elridge, B.F. and Edman, J.D. 2004. Medical Entomology: A Textbook on Public Health and

Cambodians in Hawaii and Their Relation to Employment and Welfare.

ERIC Educational Resources Information Center

Riddle, Tom

This study of the unusually high level of labor force participation in the Hawaiian Cambodian community includes descriptions of what Cambodians do in Hawaii, demographic descriptions of the community and household units, a description of the influence of the welfare system on the Cambodian community, and ethnographic descriptions of the lives of…

United States Air Force Training Line Simulator. Final Report.

ERIC Educational Resources Information Center

Nauta, Franz; Pierce, Michael B.

This report describes the technical aspects and potential applications of a computer-based model simulating the flow of airmen through basic training and entry-level technical training. The objective of the simulation is to assess the impacts of alternative recruit classification and training policies under a wide variety of assumptions regarding…

Faces and Future of the Nonmetro Workforce.

ERIC Educational Resources Information Center

Swanson, Linda L.; Butler, Margaret A.

Due largely to outmigration of young people, the nonmetropolitan United States has a lower proportion of people in the prime working ages of 20-44 than do metropolitan areas. Discouraged workers and high levels of work-preventing disabilities have contributed to lower rates of nonmetropolitan labor force participation for each age group between 20…

Institutional Profiles of CAATE Accredited Entry-Level Athletic Training Education Programs in the United States

ERIC Educational Resources Information Center

Rich, Valerie J.; Kedrowski, Jonathan J.; Richter, Scott

2008-01-01

Context: Educational reform has recently become common thread in athletic training education. The National Athletic Trainers' Association (NATA) Education Task force suggests that Athletic Training Education Programs (ATEPs) align within colleges of health-related professions and offer academic majors. Objective: To provide a current profile of…

The Cost to Industry. Basic Skills and the UK Workforce.

ERIC Educational Resources Information Center

Adult Literacy and Basic Skills Unit, London (England).

In Fall 1992, 400 telephone interviews established levels of basic skills difficulties among the work force as encountered or perceived by employers in the United Kingdom. Costs to employers of poor basic skills and the effect of these on their operation were quantified and described. Respondents were mainly personnel/training managers or…

Design and Test of a Soft Plantar Force Measurement System for Gait Detection

PubMed Central

Zhang, Xuefeng; Zhao, Yulong; Duan, Zhengyong; Liu, Yan

2012-01-01

This work describes a plantar force measurement system. The MEMS pressure sensor, as the key sensing element, is designed, fabricated and embedded into a flexible silicon oil-filled bladder made of silicon rubber to constitute a single sensing unit. A conditioning circuit is designed for signal processing and data acquisition. The characteristics of the plantar force sensing unit are investigated by both static and dynamic tests. A comparison of characteristics between the proposed plantar force sensing unit and a commercial flexible force sensor is presented. A practical experiment of plantar force measurement has been carried out to validate the system. The results demonstrate that the proposed measurement system has a potential for success in the application of plantar force measurement during normal gait. PMID:23208558

Hydrogeologic framework and ground-water resources at Seymour Johnson Air Force Base, North Carolina

USGS Publications Warehouse

Cardinell, A.P.; Howe, S.S.

1997-01-01

A preliminary hydrogeologic framework of the Seymour Johnson Air Force Base was constructed from published data, available well data, and reports from Air Base files, City of Goldsboro and Wayne County records, and North Carolina Geological Survey files. Borehole geophysical logs were run in selected wells; and the surficial, Black Creek, and upper Cape Fear aquifers were mapped. Results indicate that the surficial aquifer appears to have the greatest lateral variability of clay units and aquifer material of the three aquifers. A surficial aquifer water-level surface map, constructed from selected monitoring wells screened exclusively in the surficial aquifer, indicates the general direction of ground-water movement in this mostly unconfined aquifer is toward the Neuse River and Stoney Creek. However, water-level gradient data from a few sites in the surficial aquifer did not reflect this trend, and there are insufficient hydrologic and hydrogeologic data to determine the cause of these few anamalous measurements. The Black Creek aquifer underlies the surficial aquifer and is believed to underlie most of Wayne County, including the Air Base where the aquifer and overlying confining unit are estimated from well log data to be as much as 100 feet thick. The Black Creek confining unit ranges in thickness from less than 8 feet to more than 20 feet. There are currently no accessible wells screened exclusively in the Black Creek aquifer from which to measure water levels. The upper Cape Fear aquifer and confining unit are generally found at depths greater than 80 feet below land surface at the Air Base, and are estimated to be as much as 70 feet thick. Hydrologic and hydrogeologic data are insufficient to determine localized surficial aquifer hydrogeology, ground-water movement at several sites, or hydraulic head differences between the three aquifers.

Strategic Choice: United States Special Forces’ Comparative Advantage in Irregular Warfare

DTIC Science & Technology

2017-03-01

UNITED STATES SPECIAL FORCES’ COMPARATIVE ADVANTAGE IN IRREGULAR WARFARE by Steven F. Payne March 2017 Thesis Advisor: Hy S. Rothstein...REPORT TYPE AND DATES COVERED Master’s thesis 4. TITLE AND SUBTITLE STRATEGIC CHOICE: UNITED STATES SPECIAL FORCES’ COMPARATIVE ADVANTAGE IN...methodology, this thesis concludes that U.S. Army Special Forces have a comparative advantage over conventional forces to provide the National Command

Effect of hinge-moment parameters on elevator stick forces in rapid maneuvers

NASA Technical Reports Server (NTRS)

Jones, R. T.; Greenberg, H.

1976-01-01

The importance of the stick force per unit normal acceleration as a criterion of longitudinal stability and the critical dependence of this gradient on elevator hinge moment parameters are investigated with special reference to transient effects for maneuvers of short duration. The analysis shows that different combinations of elevator parameters, which give the same stick force per unit acceleration in turns, give widely different force variations during the entries into and recoveries from steady turns and during maneuvers of short duration such as abrupt pull-ups. The stick force per unit acceleration is greater for abrupt than for gradual control movements.

Fluctuations in isometric muscle force can be described by one linear projection of low-frequency components of motor unit discharge rates

PubMed Central

Negro, Francesco; Holobar, Aleš; Farina, Dario

2009-01-01

The aim of the study was to investigate the relation between linear transformations of motor unit discharge rates and muscle force. Intramuscular (wire electrodes) and high-density surface EMG (13 × 5 electrode grid) were recorded from the abductor digiti minimi muscle of eight healthy men during 60 s contractions at 5%, 7.5% and 10% of the maximal force. Spike trains of a total of 222 motor units were identified from the EMG recordings with decomposition algorithms. Principal component analysis of the smoothed motor unit discharge rates indicated that one component (first common component, FCC) described 44.2 ± 7.5% of the total variability of the smoothed discharge rates when computed over the entire contraction interval and 64.3 ± 10.2% of the variability when computed over 5 s intervals. When the FCC was computed from four or more motor units per contraction, it correlated with the force produced by the muscle (62.7 ± 10.1%) by a greater degree (P < 0.001) than the smoothed discharge rates of individual motor units (41.4 ± 7.8%). The correlation between FCC and the force signal increased up to 71.8 ± 13.1% when the duration and the shape of the smoothing window for discharge rates were similar to the average motor unit twitch force. Moreover, the coefficients of variation (CoV) for the force and for the FCC signal were correlated in all subjects (R2 range = 0.14–0.56; P < 0.05) whereas the CoV for force was correlated to the interspike interval variability in only one subject (R2= 0.12; P < 0.05). Similar results were further obtained from measures on the tibialis anterior muscle of an additional eight subjects during contractions at forces up to 20% of the maximal force (e.g. FCC explained 59.8 ± 11.0% of variability of the smoothed discharge rates). In conclusion, one signal captures most of the underlying variability of the low-frequency components of motor unit discharge rates and explains large part of the fluctuations in the motor output during isometric contractions. PMID:19840996

Fluctuations in isometric muscle force can be described by one linear projection of low-frequency components of motor unit discharge rates.

PubMed

Negro, Francesco; Holobar, Ales; Farina, Dario

2009-12-15

The aim of the study was to investigate the relation between linear transformations of motor unit discharge rates and muscle force. Intramuscular (wire electrodes) and high-density surface EMG (13 x 5 electrode grid) were recorded from the abductor digiti minimi muscle of eight healthy men during 60 s contractions at 5%, 7.5% and 10% of the maximal force. Spike trains of a total of 222 motor units were identified from the EMG recordings with decomposition algorithms. Principal component analysis of the smoothed motor unit discharge rates indicated that one component (first common component, FCC) described 44.2 +/- 7.5% of the total variability of the smoothed discharge rates when computed over the entire contraction interval and 64.3 +/- 10.2% of the variability when computed over 5 s intervals. When the FCC was computed from four or more motor units per contraction, it correlated with the force produced by the muscle (62.7 +/- 10.1%) by a greater degree (P < 0.001) than the smoothed discharge rates of individual motor units (41.4 +/- 7.8%). The correlation between FCC and the force signal increased up to 71.8 +/- 13.1% when the duration and the shape of the smoothing window for discharge rates were similar to the average motor unit twitch force. Moreover, the coefficients of variation (CoV) for the force and for the FCC signal were correlated in all subjects (R(2) range = 0.14-0.56; P < 0.05) whereas the CoV for force was correlated to the interspike interval variability in only one subject (R(2) = 0.12; P < 0.05). Similar results were further obtained from measures on the tibialis anterior muscle of an additional eight subjects during contractions at forces up to 20% of the maximal force (e.g. FCC explained 59.8 +/- 11.0% of variability of the smoothed discharge rates). In conclusion, one signal captures most of the underlying variability of the low-frequency components of motor unit discharge rates and explains large part of the fluctuations in the motor output during isometric contractions.

U.S. Air Force Live | The Official Blog of the United States Air Force

Science.gov Websites

. Christopher Uecker, 25th Aircraft Maintenance Unit weapons load crew team chief, tightens a guided bomb unit Uecker, 25th Aircraft Maintenance Unit weapons load crew team chief, tightens a guided bomb unit onto an Maintenance Unit load munitions onto an A-10 Thunderbolt II during the Vigilant Ace 16 exercise on Osan Air

New Results on a Stochastic Duel Game with Each Force Consisting of Heterogeneous Units

DTIC Science & Technology

2013-02-01

NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA NEW RESULTS ON A STOCHASTIC DUEL GAME WITH EACH FORCE CONSISTING OF...on a Stochastic Duel Game With Each Force Consisting of Heterogeneous Units 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER...distribution is unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT Two forces engage in a duel , with each force initially consisting of several

Simulation of the Indirect Radiative Forcing of Climate Due to Aerosols by the Two-Way Coupled WRF-CMAQ over the Eastern United States

EPA Science Inventory

In this study, the shortwave cloud forcing (SWCF) and longwave cloud forcing (LWCF) are estimated with the newly developed two-way coupled WRF-CMAQ over the eastern United States. Preliminary indirect aerosol forcing has been successfully implemented in WRF-CMAQ. The comparisons...

Bimanual Force Coordination in Children with Spastic Unilateral Cerebral Palsy

ERIC Educational Resources Information Center

Smits-Engelsman, B. C. M.; Klingels, K.; Feys, H.

2011-01-01

In this study bimanual grip-force coordination was quantified using a novel "Gripper" system that records grip forces produced while holding a lower and upper unit, in combination with the lift force necessary to separate these units. Children with unilateral cerebral palsy (CP) (aged 5-14 years, n = 12) were compared to age matched typically…

Portfolio theory of optimal isometric force production: Variability predictions and nonequilibrium fluctuation dissipation theorem

NASA Astrophysics Data System (ADS)

Frank, T. D.; Patanarapeelert, K.; Beek, P. J.

2008-05-01

We derive a fundamental relationship between the mean and the variability of isometric force. The relationship arises from an optimal collection of active motor units such that the force variability assumes a minimum (optimal isometric force). The relationship is shown to be independent of the explicit motor unit properties and of the dynamical features of isometric force production. A constant coefficient of variation in the asymptotic regime and a nonequilibrium fluctuation-dissipation theorem for optimal isometric force are predicted.

Motor unit recruitment and bursts of activity in the surface electromyogram during a sustained contraction.

PubMed

Riley, Zachary A; Terry, Mary E; Mendez-Villanueva, Alberto; Litsey, Jane C; Enoka, Roger M

2008-06-01

Bursts of activity in the surface electromyogram (EMG) during a sustained contraction have been interpreted as corresponding to the transient recruitment of motor units, but this association has never been confirmed. The current study compared the timing of trains of action potentials discharged by single motor units during a sustained contraction with the bursts of activity detected in the surface EMG signal. The 20 motor units from 6 subjects [recruitment threshold, 35.3 +/- 11.3% maximal voluntary contraction (MVC) force] that were detected with fine wire electrodes discharged 2-9 trains of action potentials (7.2 +/- 5.6 s in duration) when recruited during a contraction that was sustained at a force below its recruitment threshold (target force, 25.4 +/- 10.6% MVC force). High-pass filtering the bipolar surface EMG signal improved its correlation with the single motor unit signal. An algorithm applied to the surface EMG was able to detect 75% of the trains of motor unit action potentials. The results indicate that bursts of activity in the surface EMG during a constant-force contraction correspond to the transient recruitment of higher-threshold motor units in healthy individuals, and these results could assist in the diagnosis and design of treatment in individuals who demonstrate deficits in motor unit activation.

75 FR 22573 - Privacy Act of 1974; System of Records

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-29

... Force Automated Education Management System (AFAEMS). System location: Headquarters United States Air... Education Branch, Education Division, Directorate of Personnel Force Development, Headquarters United States.... F036 AF PC U System name: Air Force Automated Education Management System (AFAEMS) (January 28, 2002...

Resilience, Stress, Stigma, and Barriers to Mental Healthcare in U.S. Air Force Nursing Personnel.

PubMed

Hernandez, Stephen H A; Morgan, Brenda J; Parshall, Mark B

Stigma may deter military service members from seeking mental health (MH) services. Previously, substantial proportions of U.S. Air Force (USAF) registered nurses and medical technicians reported concerns about stigma with accessing MH services; in particular, that unit members might lose confidence in them or perceive them as weak, unit leadership might treat them differently, or accessing care might affect career advancement. This study assessed the extent to which stigma and barriers to accessing MH services as perceived by USAF nursing personnel are associated with resilience, stress, previous deployment, or demographic characteristics. An anonymous, online survey was administered to active-duty USAF registered nurses and medical technicians at three locations (N = 250). The survey included demographic items, the Stigma and Barriers to Care scales, Conner-Davidson Resilience Scale, and Perceived Stress Questionnaire. Mean resilience was high, and perceived stress was moderate. About half of participants agreed that unit members might have less confidence in me (54%) or unit leadership might treat me differently (58%). Many also had concerns that it would harm my career (47%), I would be seen as weak (47%), or there would be difficulty getting time off work for treatment (45%). Stigma was positively correlated with perceived stress (r = .40, p < .01) and negatively correlated with resilience (r = -.24, p < .01). Officers had significantly higher stigma and resilience scores and lower stress scores compared with enlisted personnel, but those differences were small. This study validated previous findings that substantial percentages of USAF nursing personnel have concerns that accessing MH services may adversely affect their careers and how they are viewed by unit leaders and peers. In addition, higher levels of concern about stigma were associated with higher levels of stress and lower levels of resilience. Limitations included a low response rate (18%) and self-selection biases.

Environmental Security in the Danube River Basin: Policy Implications for the United States

DTIC Science & Technology

1999-01-01

United Nations Environmental Programme and Centre for Human Settlements jointly formed a Balkans Task Force that has been conducting independent and...1199 V ACKNOWLEDGMENTS I would like to thank the United States Air Force Institute for National Security Studies (TNSS) and the Army Environmental...regularly scheduled course on Responsibilities of Military Forces in Environmental Protection. Mr. Robert Jarrett of AEPI provided valuable review

United States Air Force Security Forces in an Era of Terrorist Threats

DTIC Science & Technology

1999-06-01

their primary duties. The third alternative is to eliminate the Palace Tenure deployments of security personnel and replace them with dedicated units...The Phoenix Raven program, the 820th Security Forces Group, and Palace Tenure commitments. The specified mission varies by organization, but the...820th Security Forces Group. January 1999, slide 4. 166 Statement of LT. Col. Larry A. Buckingham , 820th Security Forces Group Commander, “820th Security

Sources and Levels of Stress among 70th Intelligence, Surveillance, and Reconnaissance Wing Intelligence Operators and Support Personnel

DTIC Science & Technology

2013-03-01

personnel had responses indicative of the syndrome of burnout (i.e., simultaneously reporting high exhaustion, high cynicism, and low professional...as well as levels of burnout , psychological distress, and post-traumatic stress disorder symptoms among United States Air Force 70th Intelligence...revealed lower rates of burnout and psychological distress among 70 ISRW personnel when compared to intelligence operators in other arenas of the 25th Air

Catalog of Simulation Models and Wargames Used for Unit and Leader Training. Second Edition.

DTIC Science & Technology

1987-01-01

College; two or three brigade level games per year at brigade groups. In past - have played corps level games at Canadian Forces Command and Staff College...dedicated PERQ microcomputer Data Output Analysis: 5 minutes (generation of killer/victim scoreboard) Frequency of use: 4 times per year Users: HEL...classification: UNCLASSIFIED Frequency of use: 3 plays per year . Users: Training Gps, TF HQ and Infantry Centre. (The p. settings are changed to suit each

Protecting Secure Facilities From Underground Intrusion Using Seismic/Acoustic Sensor Arrays

DTIC Science & Technology

2009-08-01

the upper 6 meters of sediments were deposited as part of a delta during a time of higher sea level, when low-gradient rivers carried fine-grained...geological site characterization and stratigraphy and sedimentation processes. Dr. Jason R. McKenna is a geophysicist at the United States Army Engineer...doctrine is being revised to address the engineer force structure at all levels to ensure that emerging lessons learned from Iraq and Afghanistan are

Combat aircraft operations: Training requirements for the German Air Force tactical flying units and the noise problem

NASA Astrophysics Data System (ADS)

Jertz, W.

1992-04-01

The deterrence potential of an Air Force, and by that the capability to fulfill their mission in times of war, relies on threat oriented training in peacetime. Low level flying is a major tactical means to help aircrews reduce the anticipated threat imposed to them by enemy air defence systems to an acceptable degree. The demand for this capability applies also to air defence tasks against attacking fighter bombers. Military low level flying requires a high degree of proficiency, which can only be reached and maintained by constant training. A high performance level is then the key to air power. The possibilities for this kind of necessary training are restricted by superior demands concerning, amongst others, flying safety and environmental reasons. Too intensive restrictions might reduce the fighting capability of the wings to such an extent, that mission fulfillment could be seriously endangered.

Use of Dynamic Models and Operational Architecture to Solve Complex Navy Challenges

NASA Technical Reports Server (NTRS)

Grande, Darby; Black, J. Todd; Freeman, Jared; Sorber, TIm; Serfaty, Daniel

2010-01-01

The United States Navy established 8 Maritime Operations Centers (MOC) to enhance the command and control of forces at the operational level of warfare. Each MOC is a headquarters manned by qualified joint operational-level staffs, and enabled by globally interoperable C41 systems. To assess and refine MOC staffing, equipment, and schedules, a dynamic software model was developed. The model leverages pre-existing operational process architecture, joint military task lists that define activities and their precedence relations, as well as Navy documents that specify manning and roles per activity. The software model serves as a "computational wind-tunnel" in which to test a MOC on a mission, and to refine its structure, staffing, processes, and schedules. More generally, the model supports resource allocation decisions concerning Doctrine, Organization, Training, Material, Leadership, Personnel and Facilities (DOTMLPF) at MOCs around the world. A rapid prototype effort efficiently produced this software in less than five months, using an integrated process team consisting of MOC military and civilian staff, modeling experts, and software developers. The work reported here was conducted for Commander, United States Fleet Forces Command in Norfolk, Virginia, code N5-0LW (Operational Level of War) that facilitates the identification, consolidation, and prioritization of MOC capabilities requirements, and implementation and delivery of MOC solutions.

Assessing altered motor unit recruitment patterns in paretic muscles of stroke survivors using surface electromyography

NASA Astrophysics Data System (ADS)

Hu, Xiaogang; Suresh, Aneesha K.; Rymer, William Z.; Suresh, Nina L.

2015-12-01

Objective. The advancement of surface electromyogram (sEMG) recording and signal processing techniques has allowed us to characterize the recruitment properties of a substantial population of motor units (MUs) non-invasively. Here we seek to determine whether MU recruitment properties are modified in paretic muscles of hemispheric stroke survivors. Approach. Using an advanced EMG sensor array, we recorded sEMG during isometric contractions of the first dorsal interosseous muscle over a range of contraction levels, from 20% to 60% of maximum, in both paretic and contralateral muscles of stroke survivors. Using MU decomposition techniques, MU action potential amplitudes and recruitment thresholds were derived for simultaneously activated MUs in each isometric contraction. Main results. Our results show a significant disruption of recruitment organization in paretic muscles, in that the size principle describing recruitment rank order was materially distorted. MUs were recruited over a very narrow force range with increasing force output, generating a strong clustering effect, when referenced to recruitment force magnitude. Such disturbances in MU properties also correlated well with the impairment of voluntary force generation. Significance. Our findings provide direct evidence regarding MU recruitment modifications in paretic muscles of stroke survivors, and suggest that these modifications may contribute to weakness for voluntary contractions.

Assessing altered motor unit recruitment patterns in paretic muscles of stroke survivors using surface electromyography

PubMed Central

Hu, Xiaogang; Suresh, Aneesha K; Rymer, William Z; Suresh, Nina L

2017-01-01

Objective The advancement of surface electromyogram (sEMG) recording and signal processing techniques has allowed us to characterize the recruitment properties of a substantial population of motor units (MUs) non-invasively. Here we seek to determine whether MU recruitment properties are modified in paretic muscles of hemispheric stroke survivors. Approach Using an advanced EMG sensor array, we recorded sEMG during isometric contractions of the first dorsal interosseous muscle over a range of contraction levels, from 20% to 60% of maximum, in both paretic and contralateral muscles of stroke survivors. Using MU decomposition techniques, MU action potential amplitudes and recruitment thresholds were derived for simultaneously activated MUs in each isometric contraction. Main results Our results show a significant disruption of recruitment organization in paretic muscles, in that the size principle describing recruitment rank order was materially distorted. MUs were recruited over a very narrow force range with increasing force output, generating a strong clustering effect, when referenced to recruitment force magnitude. Such disturbances in MU properties also correlated well with the impairment of voluntary force generation. Significance Our findings provide direct evidence regarding MU recruitment modifications in paretic muscles of stroke survivors, and suggest that these modifications may contribute to weakness for voluntary contractions. PMID:26402920

Fatigability of rat hindlimb muscle: associations between electromyogram and force during a fatigue test.

PubMed Central

Enoka, R M; Rankin, L L; Stuart, D G; Volz, K A

1989-01-01

1. An experimental protocol designed to assess fatigability in motor units (Burke, Levine, Tsairis & Zajac, 1973) has been applied to the whole muscles of anaesthetized adult rats, and the association between the electromyogram (EMG) and force was monitored over the course of the test. 2. Both test muscles (soleus and extensor digitorum longus) exhibited a wide range of fatigability, which was defined as the decline in isometric peak force at 6 min, such that the data could be separated into five levels of fatigability. Fatigue indices for each test muscle were distributed across three levels. 3. The EMG was quantified with four measures of amplitude, four of duration, and one interaction term (area). Correlation analyses indicated that the EMG was adequately represented by one measure of amplitude (absolute amplitude), one of duration (peak-to-peak duration) and area. The best single measure was area. 4. The EMG-force associations for soleus varied markedly among its three fatigability groups. In contrast, over the course of the test, all three extensor digitorum longus groups displayed qualitatively similar EMG-force associations. 5. Multiple regression analyses indicated that the EMG parameters were able to predict peak force better for extensor digitorum longus than for soleus. Furthermore, for both test muscle, the prediction was best for the most fatigable group. 6. The associations between EMG and force exhibited three patterns for the two test muscles and three levels of fatigability. These differences suggested variation in the mechanisms, related to both fibre-type composition and susceptibility to fatigue, that dictate the performance elicited by this particular stimulus regimen. The mechanisms seem to include both intracellular and transmission processes. Images Fig. 1 PMID:2778729

Collaborative Research on and Successful Implementation of Factory-Level Repellent-Treated Marine Corps Combat Utility Uniforms from 2004-2007

USDA-ARS?s Scientific Manuscript database

In August, 2003, a mission to protect an airfield in Monrovia, Liberia failed after 80 of 150 multi-force personnel were infected with the malaria parasite. Over 70 of these personnel were United States Marines. In October, 2003, the representatives from the U.S. Marine Corps requested assistance ...

Where the Butterfly Alights: The Global Location of eWork. EMERGENCE. IES Report 378.

ERIC Educational Resources Information Center

Huws, U.; Jagger, N.; Bates, P.

This study forms part of the EMERGENCE project, which is designed to measure and map information and communications technology-related employment (eWork) relocation on a global level. Information collected by Eurostat and the United Kingdom Labour Force Survey were the primary sources of data analyzed. Twelve factors identified as influencing…

Recruitment of motor units in the medial gastrocnemius muscle during human quiet standing: is recruitment intermittent? What triggers recruitment?

PubMed Central

Loram, Ian D.; Muceli, Silvia; Merletti, Roberto; Farina, Dario

2012-01-01

The recruitment and the rate of discharge of motor units are determinants of muscle force. Within a motoneuron pool, recruitment and rate coding of individual motor units might be controlled independently, depending on the circumstances. In this study, we tested whether, during human quiet standing, the force of the medial gastrocnemius (MG) muscle is predominantly controlled by recruitment or rate coding. If MG control during standing was mainly due to recruitment, then we further asked what the trigger mechanism is. Is it determined internally, or is it related to body kinematics? While seven healthy subjects stood quietly, intramuscular electromyograms were recorded from the MG muscle with three pairs of wire electrodes. The number of active motor units and their mean discharge rate were compared for different sway velocities and positions. Motor unit discharges occurred more frequently when the body swayed faster and forward (Pearson R = 0.63; P < 0.0001). This higher likelihood of observing motor unit potentials was explained chiefly by the recruitment of additional units. During forward body shifts, the median number of units detected increased from 3 to 11 (P < 0.0001), whereas the discharge rate changed from 8 ± 1.1 (mean ± SD) to 10 ± 0.9 pulses/s (P = 0.001). Strikingly, motor units did not discharge continuously throughout standing. They were recruited within individual, forward sways and intermittently, with a modal rate of two recruitments per second. This modal rate is consistent with previous circumstantial evidence relating the control of standing to an intrinsic, higher level planning process. PMID:21994258

Recruitment of motor units in the medial gastrocnemius muscle during human quiet standing: is recruitment intermittent? What triggers recruitment?

PubMed

Vieira, Taian M M; Loram, Ian D; Muceli, Silvia; Merletti, Roberto; Farina, Dario

2012-01-01

The recruitment and the rate of discharge of motor units are determinants of muscle force. Within a motoneuron pool, recruitment and rate coding of individual motor units might be controlled independently, depending on the circumstances. In this study, we tested whether, during human quiet standing, the force of the medial gastrocnemius (MG) muscle is predominantly controlled by recruitment or rate coding. If MG control during standing was mainly due to recruitment, then we further asked what the trigger mechanism is. Is it determined internally, or is it related to body kinematics? While seven healthy subjects stood quietly, intramuscular electromyograms were recorded from the MG muscle with three pairs of wire electrodes. The number of active motor units and their mean discharge rate were compared for different sway velocities and positions. Motor unit discharges occurred more frequently when the body swayed faster and forward (Pearson R = 0.63; P < 0.0001). This higher likelihood of observing motor unit potentials was explained chiefly by the recruitment of additional units. During forward body shifts, the median number of units detected increased from 3 to 11 (P < 0.0001), whereas the discharge rate changed from 8 ± 1.1 (mean ± SD) to 10 ± 0.9 pulses/s (P = 0.001). Strikingly, motor units did not discharge continuously throughout standing. They were recruited within individual, forward sways and intermittently, with a modal rate of two recruitments per second. This modal rate is consistent with previous circumstantial evidence relating the control of standing to an intrinsic, higher level planning process.

USAF Bioenvironmental Noise Data Handbook. Volume 167: MA-3M air conditioner

NASA Astrophysics Data System (ADS)

Rau, T. H.

1982-06-01

The MA-3M is an electric motor-driven air conditioner designed to cool electronic equipment on aircraft during ground maintenance. This report provides measured and extrapolated data defining the bioacoustic environments produced by this unit operating at a normal rated condition. Near-field data are reported for 37 locations in a wide variety of physical and psychoacoustic measures: overall and band sound pressure levels, C-weighted and A-weighted sound levels, preferred speech interference levels, perceived noise levels, and limiting times for total daily exposure of personnel with and without standard Air Force ear protectors.

1. Credit USAF, ca. 1942. Original housed in the Muroc ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. Credit USAF, ca. 1942. Original housed in the Muroc Flight Test Base, Unit History, 1 September 1942 - 30 June 1945. Alfred F. Simpson Historical Research Agency. United States Air Force. Maxwell AFB, Alabama. Historical view looks west southwest at construction of Building 4317, Deluge Water Pumping Station (then designated Pump House No. 3). This in-ground structure houses fire pumps which draw water from an in-ground reservoir, Building 4316 (See HAER photos CA-170-I). Pumping station was built in-ground to take advantage of gravity, since water flows from reservoir to prime the pumps, and fire system piping is underground. Opening in far wall is to stairs leading up to ground level. Earth mound in background is part of water reservoir construction (Building 4316). - Edwards Air Force Base, North Base, Deluge Water Pumping Station, Near Second & D Streets, Boron, Kern County, CA

[Improvement of medical equipment setting for the hospital link of the medical service during wartime].

PubMed

Miroshnichenko, Yu V; Goryachev, A B; Popov, A A; Rodionov, E O

2016-04-01

One of the priorities of the military health care is to improve the system of rationing medical equipment for the hospital unit of the medical service of the Armed Forces in wartime. This is determined the fact that the effectiveness of measures to provide military field hospitals with medical supplies depends on the quality of medical care for the wounded and sick, as well as the level of their return to duty. The article presents the characteristics of modern standards medical supplies procurement of military field hospitals included in the new regulatory legal act of the Russian Federation Ministry of Defence--"Standards of supplies medical supplies medical and pharmaceutical organizations (units) of the Russian Federation on the wartime armed forces", approved and put into effect in 2015 by order of the Minister of Defence of the Russian Federation.

Theoretical Study on the Mechanics of the Conjunct Gnatoprothetic Devices in the Context of Occlusive Function Rehabilitation

PubMed Central

POPESCU, M.R.; TRANĂ, F.; MANOLEA, H.; RAUTEN, ANE-MARIE; ȘURLIN, PETRA; DRAGOMIR, L.P.

2014-01-01

The partially intercalated edentation offers the practitioner the possibility of the functional rehabilitation of the dental arcades through conjunct gnato-prosthetic devices. The functions of the dento-maxilar device, disturbed by the presence of edentation, require a treatment approach so that, without pre-planning or estimating, the result can lead most of the times to failure in terms of functionality. Clinical evaluation associated with pre- and proprosthetic treatment can also impose, in some situations the evaluation of the dental units involved in prosthetic rehabilitation. The association and implementation of the prosthetic construction in the occlusive-articular ensemble, as well as the counterbalancing of the mastication forces per dental unit and whole interarch system, linked to the distribution of the forces at the level of the pillar teeth and prosthetic construction, represent the goal of this theoretical study. PMID:25729593

Theoretical study on the mechanics of the conjunct gnatoprothetic devices in the context of occlusive function rehabilitation.

PubMed

Popescu, M R; Trană, F; Manolea, H; Rauten, Ane-Marie; Șurlin, Petra; Dragomir, L P

2014-01-01

The partially intercalated edentation offers the practitioner the possibility of the functional rehabilitation of the dental arcades through conjunct gnato-prosthetic devices. The functions of the dento-maxilar device, disturbed by the presence of edentation, require a treatment approach so that, without pre-planning or estimating, the result can lead most of the times to failure in terms of functionality. Clinical evaluation associated with pre- and proprosthetic treatment can also impose, in some situations the evaluation of the dental units involved in prosthetic rehabilitation. The association and implementation of the prosthetic construction in the occlusive-articular ensemble, as well as the counterbalancing of the mastication forces per dental unit and whole interarch system, linked to the distribution of the forces at the level of the pillar teeth and prosthetic construction, represent the goal of this theoretical study.

Corrective lens use and refractive error among United States Air Force aircrew.

PubMed

Wright, Steve T; Ivan, Douglas J; Clark, Patrick J; Gooch, John M; Thompson, William

2010-03-01

Corrective lens use by military aviators is an important consideration in the design of head-mounted equipment. The United States Air Force (USAF) has periodically monitored lens use by aviators; however, it has been over a decade since the last study. We provide an update on the prevalence of corrective lenses and refractive error among USAF aircrew based on eyeglass orders processed through the Spectacle Request Transmission System (SRTS). Currently, 41% of active duty USAF pilots and 54% of other aircrew require corrective lenses to perform flight duties. Refractive errors are characterized by low to moderate levels of myopia with a mean spherical equivalent power of -1.01 diopters (D) for pilots and -1.68 D for others. Contact lenses, and more recently refractive surgery, reduce the number of aircrew that must rely on spectacles when flying; however, spectacle compatibility remains an important consideration in the cockpit.

Modeling and test of a kinaesthetic actuator based on MR fluid for haptic applications.

PubMed

Yang, Tae-Heon; Koo, Jeong-Hoi; Kim, Sang-Youn; Kwon, Dong-Soo

2017-03-01

Haptic display units have been widely used for conveying button sensations to users, primarily employing vibrotactile actuators. However, the human feeling for pressing buttons mainly relies on kinaesthetic sensations (rather than vibrotactile sensations), and little studies exist on small-scale kinaesthetic haptic units. Thus, the primary goals of this paper are to design a miniature kinaesthetic actuator based on Magneto-Rheological (MR) fluid that can convey various button-clicking sensations and to experimentally evaluate its haptic performance. The design focuses of the proposed actuator were to produce sufficiently large actuation forces (resistive forces) for human users in a given size constraint and to offer a wide range of actuation forces for conveying vivid haptic sensations to users. To this end, this study first performed a series of parametric studies using mathematical force models for multiple operating modes of MR fluid in conjunction with finite element electromagnetism analysis. After selecting design parameters based on parametric studies, a prototype actuator was constructed, and its performance was evaluated using a dynamic mechanical analyzer. It measured the actuator's resistive force with a varying stroke (pressed depth) up to 1 mm and a varying input current from 0 A to 200 mA. The results show that the proposed actuator creates a wide range of resistive forces from around 2 N (off-state) to over 9.5 N at 200 mA. In order to assess the prototype's performance in the terms of the haptic application prospective, a maximum force rate was calculated to determine just noticeable difference in force changes for the 1 mm stoke of the actuator. The results show that the force rate is sufficient to mimic various levels of button sensations, indicating that the proposed kinaesthetic actuator can offer a wide range of resistive force changes that can be conveyed to human operators.

50 CFR 404.9 - Armed Forces actions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Wildlife and Fisheries JOINT REGULATIONS (UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE... activities and exercises of the Armed Forces (including those carried out by the United States Coast Guard... environment and admitting of no other feasible solution. (c) All activities and exercises of the Armed Forces...

3 CFR - Disestablishment of United States Joint Forces Command

Code of Federal Regulations, 2012 CFR

2012-01-01

... Command Presidential Documents Other Presidential Documents Memorandum of January 6, 2011 Disestablishment of United States Joint Forces Command Memorandum for the Secretary of Defense Pursuant to my... States Joint Forces Command, effective on a date to be determined by the Secretary of Defense. I direct...

LINKING REGIONAL AEROSOL EMISSION CHANGES WITH MULTIPLE IMPACT MEASURES THROUGH DIRECT AND CLOUD-RELATED FORCING ESTIMATES

EPA Science Inventory

Outputs expected from this project include improved confidence in direct radiative forcing and cloud radiative forcing, particularly over the United States and with regard to United States emissions publicly available, documented data sets including emission inventories of siz...

Population genetics and demography unite ecology and evolution

USGS Publications Warehouse

Lowe, Winsor H.; Kovach, Ryan; Allendorf, Fred W.

2017-01-01

The interplay of ecology and evolution has been a rich area of research for decades. A surge of interest in this area was catalyzed by the observation that evolution by natural selection can operate at the same contemporary timescales as ecological dynamics. Specifically, recent eco-evolutionary research focuses on how rapid adaptation influences ecology, and vice versa. Evolution by non-adaptive forces also occurs quickly, with ecological consequences, but understanding the full scope of ecology–evolution (eco–evo) interactions requires explicitly addressing population-level processes – genetic and demographic. We show the strong ecological effects of non-adaptive evolutionary forces and, more broadly, the value of population-level research for gaining a mechanistic understanding of eco–evo interactions. The breadth of eco-evolutionary research should expand to incorporate the breadth of evolution itself.

Medical civil-military operations: the deployed medical brigade's role in counterinsurgency operations.

PubMed

Bryan, Jeffrey; Miyamoto, Danelle; Holman, Vincent

2008-01-01

Medical civil-military operations are a critical combat multiplier directly supporting the counterinsurgency fight. Army Medical Department Soldiers support medical civil affairs activities at all levels from platoon to the United States Mission-Iraq (Department of State) initiatives enhancing the legitimacy of medical services in the Iraq Ministry of Health, Ministry of Defense, Ministry of the Interior, and Ministry of Justice. The civil-military operations mission of the deployed Task Force 62 Medical Brigade has also evolved into a broad mission encompassing over 120 contractors including Iraqi-American, Bilingual Bicultural Advisors-Subject Matter Experts serving as case management liaison officers and medical trainers, as well as Iraqi Advisor Task Force members providing medical atmospherics, assessments, training, and the overall management of Iraqi linguists supporting all level III medical facilities.

Not Again! 20th Century Hollow Force Lessons Learned for the 21st Century Military

DTIC Science & Technology

2011-06-17

capabilities in combat units . Although further research is required to determine the optimal balance between the Active and Reserve Component forces, a... UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT Joint Forces Staff College NUMBER Joint Advanced...SUPPLEMENTARY NOTES 14. ABSTRACT This paper investigates the problem of how United States Department of Defense (DoD) planners should organize the

U. S. Naval Forces, Vietnam Monthly Historical Supplement for December 1967

DTIC Science & Technology

1968-05-07

Coastal Surveillance Force 1 Operation MARKiiT TIME 1 MARKET TIME Unit 13 MARKET TIM£. Statistical Sunnary U Operation STABLE DOOR 16 River...Patrol Force 19 Rung Sfit Special Zone River Patrol Group 21 Delta Uiver Patrol Group 25 GAME WARDEN Unit 42 GAME WARDEN Statistical Sumnfixy 43...Bassac River Operations 38 GAME GARDEN Detections, Inspections, Boardings . . 44 TF 117 units land troops in the Delta 46 CAFT SALZiÄ relieves CAPT

Motor Unit Number Estimate and Isometric Hand Grip Strength in Military Veterans with or Without Muscular Complaints: Reference Values for Longitudinal Follow-up.

PubMed

Li, Mian; Yao, Wenguo; Sundahl, Cynthia

2018-03-26

It remains unclear if Gulf War (GW) veterans have a higher risk of developing motor neuron disorder. We intended to establish baseline neurophysiological values, including thenar motor unit number estimate (MUNE) and isometric hand grip (IHG) strength, to compare future follow-ups of deployed GW veterans with or without muscular complaints. We evaluated 19 GW veterans with self-reported weakness, cramps, or excessive muscle fatigue (Ill-19) and compared them with 18 controls without such muscular complaints (C-18). We performed MUNE on hand thenar muscles using adapted multipoint stimulation method for Ill-19 and 15 controls (C-15). We measured IHG strength (maximum force, endurance, and fatigue level) on Ill-19 and C-18 with a hand dynamometer. We performed nerve conduction studies on all study participants to determine which subjects had mild carpal tunnel syndrome (CTS). We compared the MUNE and IHG strength measures between Ill group and controls and between those with CTS and those without CTS. We obtained thenar MUNE of Ill-19 (95% CI of mean: 143-215; mean age: 46 yr) and compared it with that of C-15 (95% CI of mean: 161-230; mean age: 45 yr), and 95% of CI of mean among IHG strength variables (maximum force: 324-381 Newton; endurance: 32-42 s; fatigue level: 24%-33%) compared with C-18 (maximum force: 349-408 Newton; endurance: 35-46 s; fatigue level: 21%-27%). There was no significant difference in either MUNE or IHG strength between Ill-19 group and controls. The MUNE and IHG maximum forces were significantly lower in those with CTS compared with those without CTS. As a surrogate of mild CTS, the median versus ulnar distal sensory latency on nerve conduction study was only weakly associated with MUNE, maximum force, and fatigue level, respectively. To our knowledge, no published study on MUNE reference values of military veteran population has been available. The quantifiable values of both thenar MUNE and IHG strength of military veterans serve as baselines for our longitudinal follow-up of motor neuron function of deployed troops. These reference values are also useful for other laboratories to study veterans' motor system with or without mild CTS.

The kinetics of rugby union scrummaging.

PubMed

Milburn, P D

1990-01-01

Two rugby union forward packs of differing ability levels were examined during scrummaging against an instrumented scrum machine. By systematically moving the front-row of the scrum along the scrum machine, kinetic data on each front-row forward could be obtained under all test conditions. Each forward pack was tested under the following scrummaging combinations: front-row only; front-row plus second-row; full scrum minus side-row, and full scrum. Data obtained from each scrum included the three orthogonal components of force at engagement and the sustained force applied by each front-row player. An estimate of sub-unit contributions was made by subtracting the total forward force on all three front-row players from the total for the complete scrum. Results indicated the primary role of the second-row appeared to be application of forward force. The back-row ('number eight') forward did not substantially contribute any additional forward force, and added only slightly to the lateral and vertical shear force experienced by the front-row. The side-row contributed an additional 20-27% to the forward force, but at the expense of increased vertical forces on all front-row forwards. Results of this investigation are discussed in relation to rule modification, rule interpretation and coaching.

Effect of pain on the modulation in discharge rate of sternocleidomastoid motor units with force direction.

PubMed

Falla, Deborah; Lindstrøm, Rene; Rechter, Lotte; Farina, Dario

2010-05-01

To compare the behavior of sternocleidomastoid motor units of patients with chronic neck pain and healthy controls. Nine women (age, 40.4+/-3.5 yr) with chronic neck pain and nine age- and gender-matched healthy controls participated. Surface and intramuscular EMG were recorded from the sternocleidomastoid muscle bilaterally as subjects performed isometric contractions of 10-s duration in the horizontal plane at a force of 15 N in eight directions (0-360 degrees ; 45 degrees intervals) and isometric contractions at 15 and 30 N force with continuous change in force direction in the range 0-360 degrees . Motor unit behavior was monitored during the 10-s contractions and the subsequent resting periods. The mean motor unit discharge rate depended on the direction of force in the control subjects (P<0.05) but not in the patients. Moreover, in three of the nine patients, but in none of the controls, single motor unit activity continued for 8.1+/-6.1s upon completion of the contraction. The surface EMG amplitude during the circular contraction at 15N was greater for the patients (43.5+/-54.2 microV) compared to controls (16.9+/-14.9 microV; P<0.05). The modulation in discharge rate of individual motor units with force direction is reduced in the sternocleidomastoid muscle in patients with neck pain, with some patients showing prolonged motor unit activity when they were instructed to rest. These observations suggest that chronic neck pain affects the change in neural drive to muscles with force direction. Copyright 2009 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Environmental Assessment Proposed Demolition Plan Hill Air Force Base, Utah

DTIC Science & Technology

2010-04-01

1204, Arlington VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law , no person shall be subject to a penalty...Demolition Plan Hill Air Force Base, Utah 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR( S ) 5d. PROJECT NUMBER 5e. TASK...NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME( S ) AND ADDRESS(ES) United States Air Force - Air Force Material Command,Hill Air Force

The image of motor units architecture in the mechanomyographic signal during the single motor unit contraction: in vivo and simulation study.

PubMed

Kaczmarek, P; Celichowski, J; Drzymała-Celichowska, H; Kasiński, A

2009-08-01

The mechanomyographic (MMG) signal analysis has been performed during single motor unit (MU) contractions of the rat medial gastrocnemius muscle. The MMG has been recorded as a muscle surface displacement by using a laser distance sensor. The profiles of the MMG signal let to categorize these signals for particular MUs into three classes. Class MMG-P (positive) comprises MUs with the MMG signal similar to the force signal profile, where the distance between the muscle surface and the laser sensor increases with the force increase. The class MMG-N (negative) has also the MMG profile similar to the force profile, however the MMG is inverted in comparison to the force signal and the distance measured by using laser sensor decreases with the force increase. The third class MMG-M (mixed) characterize the MMG which initially increases with the force increases and when the force exceeds some level it starts to decrease towards the negative values. The semi-pennate muscle model has been proposed, enabling estimation of the MMG generated by a single MU depending on its localization. The analysis have shown that in the semi-pennate muscle the localization of the MU and the relative position of the laser distance sensor determine the MMG profile and amplitude. Thus, proposed classification of the MMG recordings is not related to the physiological types of MUs, but only to the MU localization and mentioned sensor position. When the distance sensor is located over the middle of the muscle belly, a part of the muscle fibers have endings near the location of the sensor beam. For the MU MMG of class MMG-N the deflection of the muscle surface proximal to the sensor mainly influences the MMG recording, whereas for the MU MMG class MMG-P, it is mainly the distal muscle surface deformation. For the MU MMG of MMG-M type the effects of deformation within the proximal and distal muscle surfaces overlap. The model has been verified with experimental recordings, and its responses are consistent and adequate in comparison to the experimental data.

Experimental Methods to Characterize Nonlinear Vibration of Flapping Wing Micro Air Vehicles

DTIC Science & Technology

2007-03-01

EXPERIMENTAL METHODS TO CHARACTERIZE NONLINEAR VIBRATION OF FLAPPING WING MICRO AIR VEHICLES THESIS Adam P. Tobias, Captain, USAF...AFIT/GAE/ENY/07-M23 DEPARTMENT OF THE AIR FORCE AIR UNIVERSITY AIR FORCE INSTITUTE OF TECHNOLOGY Wright-Patterson Air Force Base, Ohio...author and do not reflect the official policy or position of the United States Air Force, Department of Defense, or the United States Government

Behavior of motor units in human biceps brachii during a submaximal fatiguing contraction.

PubMed

Garland, S J; Enoka, R M; Serrano, L P; Robinson, G A

1994-06-01

The activity of 50 single motor units was recorded in the biceps brachii muscle of human subjects while they performed submaximal isometric elbow flexion contractions that were sustained to induce fatigue. The purposes of this study were to examine the influence of fatigue on motor unit threshold force and to determine the relationship between the threshold force of recruitment and the initial interimpulse interval on the discharge rates of single motor units during a fatiguing contraction. The discharge rate of most motor units that were active from the beginning of the contraction declined during the fatiguing contraction, whereas the discharge rates of most newly recruited units were either constant or increased slightly. The absolute threshold forces of recruitment and derecruitment decreased, and the variability of interimpulse intervals increased after the fatigue task. The change in motor unit discharge rate during the fatigue task was related to the initial rate, but the direction of the change in discharge rate could not be predicted from the threshold force of recruitment or the variability in the interimpulse intervals. The discharge rate of most motor units declined despite an increase in the excitatory drive to the motoneuron pool during the fatigue task.

77 FR 30023 - Notice of Withdrawal Application and Opportunity for Public Meeting; Alaska

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-21

... Management, Interior. ACTION: Notice. SUMMARY: The United States Air Force has filed an application with the... Force King Salmon Station. This notice gives the public an opportunity to comment on the proposed action... receive a reply during normal business hours. SUPPLEMENTARY INFORMATION: The United States Air Force...

26 CFR 54.9815-2713T - Coverage of preventive health services (temporary).

Code of Federal Regulations, 2011 CFR

2011-04-01

... the current recommendations of the United States Preventive Services Task Force with respect to the... States Preventive Services Task Force with respect to the individual. The provider bills the plan for an... A or B in the current recommendations of the United States Preventive Services Task Force with...

38 CFR 38.620 - Persons eligible for burial.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Commonwealth of the Philippines, while such forces were in the service of the Armed Forces of the United States... November 1, 2000; or (ii) New Philippine Scout—a person who enlisted between October 6, 1945, and June 30, 1947, with the Armed Forces of the United States with the consent of the Philippine government...

38 CFR 38.620 - Persons eligible for burial.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Commonwealth of the Philippines, while such forces were in the service of the Armed Forces of the United States... November 1, 2000; or (ii) New Philippine Scout—a person who enlisted between October 6, 1945, and June 30, 1947, with the Armed Forces of the United States with the consent of the Philippine government...

38 CFR 38.620 - Persons eligible for burial.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Commonwealth of the Philippines, while such forces were in the service of the Armed Forces of the United States... November 1, 2000; or (ii) New Philippine Scout—a person who enlisted between October 6, 1945, and June 30, 1947, with the Armed Forces of the United States with the consent of the Philippine government...

38 CFR 38.620 - Persons eligible for burial.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Commonwealth of the Philippines, while such forces were in the service of the Armed Forces of the United States... November 1, 2000; or (ii) New Philippine Scout—a person who enlisted between October 6, 1945, and June 30, 1947, with the Armed Forces of the United States with the consent of the Philippine government...

38 CFR 38.620 - Persons eligible for burial.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Commonwealth of the Philippines, while such forces were in the service of the Armed Forces of the United States... November 1, 2000; or (ii) New Philippine Scout—a person who enlisted between October 6, 1945, and June 30, 1947, with the Armed Forces of the United States with the consent of the Philippine government...

77 FR 51981 - Proposed Collection; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-28

... DEPARTMENT OF DEFENSE Department of the Air Force [Docket ID: USAF-2012-0016] Proposed Collection; Comment Request AGENCY: United States Security Forces Center, Headquarters, DoD. ACTION: Notice. In compliance with Section 3506(c)(2)(A) of the Paperwork Reduction Act of 1995, the Office of the United States Security Forces Center, Headquarters...

Brown Bodies and Xenophobic Bullying in US Schools: Critical Analysis and Strategies for Action

ERIC Educational Resources Information Center

Bajaj, Monisha; Ghaffar-Kucher, Ameena; Desai, Karishma

2016-01-01

In this essay, Monisha Bajaj, Ameena Ghaffar-Kucher, and Karishma Desai present an evidence-based action project that seeks to interrupt and transform bullying behaviors directed at South Asian American youth in schools in the United States. In the context of this essay and project, they argue that larger macro-level forces which promote…

Contemporary Deportation Raids and Historical Memory: Mexican Expulsions in the Nineteenth Century

ERIC Educational Resources Information Center

Hernandez, Jose Angel

2010-01-01

The contemporary situation in the United States with respect to Mexican migrants has reached a level of intensity that harkens back to the mass expulsions of the 1930s and the 1950s, when millions were forcefully removed south across the border. Recent deportation raids have targeted food processing plants and other large businesses hiring migrant…

Forces. 'O' Level Teacher's Guide. Unit 1. ZIM-SCI, Zimbabwe Secondary School Science Project. Year 3.

ERIC Educational Resources Information Center

Udwin, Martin

The Zimbabwe Secondary School Science Project (ZIM-SCI) developed student study guides, corresponding teaching guides, and science kits for a low-cost science course which could be taught during the third year of secondary school without the aid of qualified teachers and conventional laboratories. This teaching guide, designed to be read in…

Forces. 'O' Level Study Guide. Unit 1. ZIM-SCI, Zimbabwe Secondary School Science Project. Year 3.

ERIC Educational Resources Information Center

Udwin, Martin

The Zimbabwe Secondary School Science Project (ZIM-SCI) developed student study guides, corresponding teaching guides, and science kits for a low-cost science course which could be taught during the third year of secondary school without the aid of qualified teachers and conventional laboratories. This ZIM-SCI study guide is a five-part unit…

A Special Kind of Ambition: The Role of Personality in The Retention of Academically Elite Teachers

ERIC Educational Resources Information Center

Jones, Brady K.

2018-01-01

Background: Creating greater stability in the teacher labor force and improving teacher quality is an important education policy priority in the United States. While there is a robust literature on the external, environmental reasons teachers stay in or leave the occupation, little is known about the role internal, person-level factors play in…

A Senior High School Social Studies Unit on Latin American History. World History Series, Bulletin No. 257.

ERIC Educational Resources Information Center

Magee, Paul

This secondary level curriculum guide provides a program and identifies materials for the history and culture of Latin America. The primary purpose of the course is to stimulate throught and to encourage students to make valid generalizations and intelligent assessments of the forces and events that have shaped the history and culture of Latin…

Counter Narco-Terrorism Program Building Force Capacity of Guatemalan Kaibiles Assisted by the United States Special Operations Forces

DTIC Science & Technology

ultimately the United States. Due to its geographical , and multiple international borders, including access to both Atlantic and Pacific littorals...therefore achieving freedom of movement causing further instability throughout the region. Because of that reason , United States has the Counter-Narco

America's Service Academies, Your Service Academies

ERIC Educational Resources Information Center

Born, Dana H.; Phillips, Andrew T.; Trainor, Timothy E.

2012-01-01

The United States Air Force Academy, United States Naval Academy, and United States Military Academy are America's three largest service academies. They are "the" primary undergraduate institutions and commissioning sources that educate and develop the officers who are expected to lead this nation's armed forces. They are special places that have…

32 CFR 9.4 - Commission personnel.

Code of Federal Regulations, 2010 CFR

2010-07-01

... TRIALS BY MILITARY COMMISSIONS OF CERTAIN NON-UNITED STATES CITIZENS IN THE WAR AGAINST TERRORISM § 9.4... United States armed forces (“Military Officer”), including without limitation reserve personnel on active... Presiding Officer shall be a Military Officer who is a judge advocate of any United States armed force. (5...

Towards a full representation of tropical cyclones in a global reanalysis of extreme sea levels

NASA Astrophysics Data System (ADS)

Muis, S.; Verlaan, M.; Lin, N.; Winsemius, H.; Vatvani, D.; Ward, P.; Aerts, J.

2016-12-01

Tropical cyclones (TCs), including hurricanes and typhoons, are characterised by high wind speeds and low pressure, and cause dangerous storm surges in coastal areas. Recent disasters like the flooding of New Orleans in 2005 due to Hurricane Katrina and of New York in 2012 due to Hurricane Sandy exemplify the significant TC risk in the United States. In this contribution, we present a new framework to model TC storm surges and probabilities at the Atlantic basin- and, ultimately, global scales. This works builds on the work of Muis et al. (2016), which presented the first dynamically-derived reanalysis dataset of storm surges that covers the entire world's coastline (GTSR dataset). Surge levels for the period 1979-2014 were simulated by forcing the Global Surge and Tide Model (GTSM) with wind speed and atmospheric pressure from the ERA-Interim reanalysis. There is generally a good agreement between simulated and observed sea level extremes in extra-tropical regions; however for areas prone to TCs there is a severe underestimation of extremes. For example, the maximum surge levels during Hurricane Katrina in New Orleans exceeded 8 m, whilst the GTSM surge levels in that area do not exceed 2-3 m. Hence, due to the coarse grid resolution, the strong intensities of TCs are not fully captured in ERA-Interim. Furthermore, the length of ERA-Interim data set, like other reanalysis datasets, is too short to estimate the probabilities of extreme TC events in a reliable way. For accurate risk assessments it is essential to improve the representation of TCs in these global reanalysis of extreme sea levels. First, we need a higher resolution of meteorological forcing, which can be modelled with input from the observed best track data. Second, we need to statistically extend the observed record to many thousands of years. We will present the first results of these steps for the east coast of the United States. We will validate the GTSM model forced with best track data using recent extreme events like Katrina and Sandy. We will investigate how the statistics of the extreme sea level will change due to improved representation of TCs.

Generalized analytical model for benthic water flux forced by surface gravity waves

USGS Publications Warehouse

King, J.N.; Mehta, A.J.; Dean, R.G.

2009-01-01

A generalized analytical model for benthic water flux forced by linear surface gravity waves over a series of layered hydrogeologic units is developed by adapting a previous solution for a hydrogeologic unit with an infinite thickness (Case I) to a unit with a finite thickness (Case II) and to a dual-unit system (Case III). The model compares favorably with laboratory observations. The amplitude of wave-forced benthic water flux is shown to be directly proportional to the amplitude of the wave, the permeability of the hydrogeologic unit, and the wave number and inversely proportional to the kinematic viscosity of water. A dimensionless amplitude parameter is introduced and shown to reach a maximum where the product of water depth and the wave number is 1.2. Submarine groundwater discharge (SGD) is a benthic water discharge flux to a marine water body. The Case I model estimates an 11.5-cm/d SGD forced by a wave with a 1 s period and 5-cm amplitude in water that is 0.5-m deep. As this wave propagates into a region with a 0.3-m-thick hydrogeologic unit, with a no-flow bottom boundary, the Case II model estimates a 9.7-cm/d wave-forced SGD. As this wave propagates into a region with a 0.2-m-thick hydrogeologic unit over an infinitely thick, more permeable unit, the Case III quasi-confined model estimates a 15.7-cm/d wave-forced SGD. The quasi-confined model has benthic constituent flux implications in coral reef, karst, and clastic regions. Waves may undermine tracer and seepage meter estimates of SGD at some locations. Copyright 2009 by the American Geophysical Union.

A Survey of Fatigue in Selected United States Air Force Shift Worker Populations

DTIC Science & Technology

2006-03-01

34 (Canadian Health Services Research Foundation, 2000, p. 1). To that end, the present study expanded upon an initial USAF assessment of shift worker ...among permanent night workers . Journal of Occupational Health , 43(6), 301-306. Gawron, V. J., French, J., & Funk, D. (2001). An overview of fatigue...HSW-PE-BR-TR-2006-0003 UNITED STATES AIR FORCE 311th Human Systems Wing A Survey of Fatigue in Selected United States Air Force Shift Worker

Successfully Demonstrating an Integrated Roofing and BIPV Solution for an Historic Building Renovation at the United States Air Force Academy

DTIC Science & Technology

2011-05-01

Solution for an Historic Building Renovation at the United States Air Force Academy • Abstract Number: 12623 Vandenberg Hall • Thin Film Solar Array • Direct...Phase 1 • Total installed production capacity: 212.320 KW DC • Panels type and quantity: • Unisolar Thin Film Amorphous Silicon Panels • 1210 – Power...Successfully Demonstrating an Integrated Roofing and BIPV Solution for an Historic Building Renovation at the United States Air Force Academy

A Muscle’s Force Depends on the Recruitment Patterns of Its Fibers

PubMed Central

Wakeling, James M.; Lee, Sabrina S. M.; Arnold, Allison S.; de Boef Miara, Maria; Biewener, Andrew A.

2012-01-01

Biomechanical models of whole muscles commonly used in simulations of musculoskeletal function and movement typically assume that the muscle generates force as a scaled-up muscle fiber. However, muscles are comprised of motor units that have different intrinsic properties and that can be activated at different times. This study tested whether a muscle model comprised of motor units that could be independently activated resulted in more accurate predictions of force than traditional Hill-type models. Forces predicted by the models were evaluated by direct comparison with the muscle forces measured in situ from the gastrocnemii in goats. The muscle was stimulated tetanically at a range of frequencies, muscle fiber strains were measured using sonomicrometry, and the activation patterns of the different types of motor unit were calculated from electromyographic recordings. Activation patterns were input into five different muscle models. Four models were traditional Hill-type models with different intrinsic speeds and fiber-type properties. The fifth model incorporated differential groups of fast and slow motor units. For all goats, muscles and stimulation frequencies the differential model resulted in the best predictions of muscle force. The in situ muscle output was shown to depend on the recruitment of different motor units within the muscle. PMID:22350666

Load type influences motor unit recruitment in biceps brachii during a sustained contraction.

PubMed

Baudry, Stéphane; Rudroff, Thorsten; Pierpoint, Lauren A; Enoka, Roger M

2009-09-01

Twenty subjects participated in four experiments designed to compare time to task failure and motor-unit recruitment threshold during contractions sustained at 15% of maximum as the elbow flexor muscles either supported an inertial load (position task) or exerted an equivalent constant torque against a rigid restraint (force task). Subcutaneous branched bipolar electrodes were used to record single motor unit activity from the biceps brachii muscle during ramp contractions performed before and at 50 and 90% of the time to failure for the position task during both fatiguing contractions. The time to task failure was briefer for the position task than for the force task (P=0.0002). Thirty and 29 motor units were isolated during the force and position tasks, respectively. The recruitment threshold declined by 48 and 30% (P=0.0001) during the position task for motor units with an initial recruitment threshold below and above the target force, respectively, whereas no significant change in recruitment threshold was observed during the force task. Changes in recruitment threshold were associated with a decrease in the mean discharge rate (-16%), an increase in discharge rate variability (+40%), and a prolongation of the first two interspike intervals (+29 and +13%). These data indicate that there were faster changes in motor unit recruitment and rate coding during the position task than the force task despite a similar net muscle torque during both tasks. Moreover, the results suggest that the differential synaptic input observed during the position task influences most of the motor unit pool.

Gold Standard Testing of Motion Based Tracking Systems

DTIC Science & Technology

2017-03-15

NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER H0L0 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT NUMBER 9...LABORATORY 711TH HUMAN PERFORMANCE WING, AIRMAN SYSTEMS DIRECTORATE, WRIGHT-PATTERSON AIR FORCE BASE, OH 45433 AIR FORCE MATERIEL COMMAND UNITED STATES AIR...711th Human Performance Wing 711th Human Performance Wing Air Force Research Laboratory Air Force Research Laboratory This report is published in the

Contributions to muscle force and EMG by combined neural excitation and electrical stimulation

NASA Astrophysics Data System (ADS)

Crago, Patrick E.; Makowski, Nathaniel S.; Cole, Natalie M.

2014-10-01

Objective. Stimulation of muscle for research or clinical interventions is often superimposed on ongoing physiological activity without a quantitative understanding of the impact of the stimulation on the net muscle activity and the physiological response. Experimental studies show that total force during stimulation is less than the sum of the isolated voluntary and stimulated forces, but the occlusion mechanism is not understood. Approach. We develop a model of efferent motor activity elicited by superimposing stimulation during a physiologically activated contraction. The model combines action potential interactions due to collision block, source resetting, and refractory periods with previously published models of physiological motor unit recruitment, rate modulation, force production, and EMG generation in human first dorsal interosseous muscle to investigate the mechanisms and effectiveness of stimulation on the net muscle force and EMG. Main results. Stimulation during a physiological contraction demonstrates partial occlusion of force and the neural component of the EMG, due to action potential interactions in motor units activated by both sources. Depending on neural and stimulation firing rates as well as on force-frequency properties, individual motor unit forces can be greater, smaller, or unchanged by the stimulation. In contrast, voluntary motor unit EMG potentials in simultaneously stimulated motor units show progressive occlusion with increasing stimulus rate. The simulations predict that occlusion would be decreased by a reverse stimulation recruitment order. Significance. The results are consistent with and provide a mechanistic interpretation of previously published experimental evidence of force occlusion. The models also predict two effects that have not been reported previously—voluntary EMG occlusion and the advantages of a proximal stimulation site. This study provides a basis for the rational design of both future experiments and clinical neuroprosthetic interventions involving either motor or sensory stimulation.

Contributions to muscle force and EMG by combined neural excitation and electrical stimulation

PubMed Central

Crago, Patrick E; Makowski, Nathaniel S; Cole, Natalie M

2014-01-01

Objective Stimulation of muscle for research or clinical interventions is often superimposed on ongoing physiological activity, without a quantitative understanding of the impact of the stimulation on the net muscle activity and the physiological response. Experimental studies show that total force during stimulation is less than the sum of the isolated voluntary and stimulated forces, but the occlusion mechanism is not understood. Approach We develop a model of efferent motor activity elicited by superimposing stimulation during a physiologically activated contraction. The model combines action potential interactions due to collision block, source resetting, and refractory periods with previously published models of physiological motor unit recruitment, rate modulation, force production, and EMG generation in human first dorsal interosseous muscle to investigate the mechanisms and effectiveness of stimulation on the net muscle force and EMG. Main Results Stimulation during a physiological contraction demonstrates partial occlusion of force and the neural component of the EMG, due to action potential interactions in motor units activated by both sources. Depending on neural and stimulation firing rates as well as on force-frequency properties, individual motor unit forces can be greater, smaller, or unchanged by the stimulation. In contrast, voluntary motor unit EMG potentials in simultaneously stimulated motor units show progressive occlusion with increasing stimulus rate. The simulations predict that occlusion would be decreased by a reverse stimulation recruitment order. Significance The results are consistent with and provide a mechanistic interpretation of previously published experimental evidence of force occlusion. The models also predict two effects that have not been reported previously - voluntary EMG occlusion and the advantages of a proximal stimulation site. This study provides a basis for the rational design of both future experiments and clinical neuroprosthetic interventions involving either motor or sensory stimulation. PMID:25242203

Nellis Air Force Base Capital Improvements Program Environmental Assessment

DTIC Science & Technology

2013-08-01

Air Force Warfare Center USC United States Code USCB United States Census Bureau USFWS United States Fish and Wildlife Service VOC Volatile...project arise with the potential to affect desert tortoise, consultation with the United States (U.S.) Fish and Wildlife Service would be initiated...Environmental Design (LEED) facilities and decrease energy consumption on military installations. The projects described in the CIP are derived

Motor unit recruitment in human biceps brachii during sustained voluntary contractions.

PubMed

Riley, Zachary A; Maerz, Adam H; Litsey, Jane C; Enoka, Roger M

2008-04-15

The purpose of the study was to examine the influence of the difference between the recruitment threshold of a motor unit and the target force of the sustained contraction on the discharge of the motor unit at recruitment. The discharge characteristics of 53 motor units in biceps brachii were recorded after being recruited during a sustained contraction. Some motor units (n = 22) discharged action potentials tonically after being recruited, whereas others (n = 31) discharged intermittent trains of action potentials. The two groups of motor units were distinguished by the difference between the recruitment threshold of the motor unit and the target force for the sustained contraction: tonic, 5.9 +/- 2.5%; intermittent, 10.7 +/- 2.9%. Discharge rate for the tonic units decreased progressively (13.9 +/- 2.7 to 11.7 +/- 2.6 pulses s(-1); P = 0.04) during the 99 +/- 111 s contraction. Train rate, train duration and average discharge rate for the intermittent motor units did not change across 211 +/- 153 s of intermittent discharge. The initial discharge rate at recruitment during the sustained contraction was lower for the intermittent motor units (11.0 +/- 3.3 pulses s(-1)) than the tonic motor units (13.7 +/- 3.3 pulses s(-1); P = 0.005), and the coefficient of variation for interspike interval was higher for the intermittent motor units (34.6 +/- 12.3%) than the tonic motor units (21.2 +/- 9.4%) at recruitment (P = 0.001) and remained elevated for discharge duration (34.6 +/- 9.2% versus 19.1 +/- 11.7%, P < 0.001). In an additional experiment, 12 motor units were recorded at two different target forces below recruitment threshold (5.7 +/- 1.9% and 10.5 +/- 2.4%). Each motor unit exhibited the two discharge patterns (tonic and intermittent) as observed for the 53 motor units. The results suggest that newly recruited motor units with recruitment thresholds closer to the target force experienced less synaptic noise at the time of recruitment that resulted in them discharging action potentials at more regular and greater rates than motor units with recruitment thresholds further from the target force.

Sprint mechanics return to competition follow-up after hamstring injury on a professional soccer player: A case study with an inertial sensor unit based methodological approach.

PubMed

Setuain, Igor; Lecumberri, Pablo; Izquierdo, Mikel

2017-10-03

The present research aimed to describe an inertial unit (IU)-based sprint mechanics evaluation model for assessing players' readiness to return to competition after suffering a grade I hamstring injury. A professional male football player (age 19years; height 177cm; weight 70kg, midfielder, Spanish, 3° Division) with a grade 1 biceps femoris injury was evaluated at pre-season, at return to play after injury and at the end of the competitive season. Sprint mechanics were analyzed via the use of an inertial orientation tracker (Xsens Technologies B.V. Enschede, Netherlands) attached over the L3-L4 region of the subject's lumbar spine. Sprint mechanics such as horizontal components of ground reaction force were assessed in both legs during sprinting actions. Findings and interpretation: Both the coefficient of the horizontal force application (SFV) and the ratio of forces (DRF) applied at increasing velocity were decreased in the injured limb compared with the contralateral healthy limb at the return to play evaluation (73% and 76% reductions, respectively) and returned to symmetrical levels at the end-season evaluation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Motor Unit Changes Seen With Skeletal Muscle Sarcopenia in Oldest Old Rats

PubMed Central

Kung, Theodore A.; van der Meulen, Jack H.; Urbanchek, Melanie G.; Kuzon, William M.; Faulkner, John A.

2014-01-01

Sarcopenia leads to many changes in skeletal muscle that contribute to atrophy, force deficits, and subsequent frailty. The purpose of this study was to characterize motor unit remodeling related to sarcopenia seen in extreme old age. Whole extensor digitorum longus muscle and motor unit contractile properties were measured in 19 adult (11–13 months) and 12 oldest old (36–37 months) Brown-Norway rats. Compared with adults, oldest old rats had significantly fewer motor units per muscle, smaller muscle cross-sectional area, and lower muscle specific force. However, mean motor unit force generation was similar between the two groups due to an increase in innervation ratio by the oldest old rats. These findings suggest that even in extreme old age both fast- and slow-twitch motor units maintain the ability to undergo motor unit remodeling that offsets some effects of sarcopenia. PMID:24077596

Atmospheric conditions during the spring and fall transitions in the coastal ocean off western United States

NASA Technical Reports Server (NTRS)

Strub, P. Ted; James, Corinne

1988-01-01

Atmospheric events which force the spring and fall oceanic transitions in the coastal ocean off the west coast of North America were examined by analyzing the records of adjusted sea level (ASL), coastal wind stress, sea level atmospheric pressure (SLP), and 500-mbar heights for the years 1971-1975 and 1980-1983. The records cover periods of 91 days, centered on the dates of the spring and fall transitions as determined from coastal ASL data. It was found that the dominant mode of the ASL and coastal wind stress are similar around the times of both the spring and fall transitions, and that the time series for these modes are highly correlated with one another. Principal estimator patterns show the spatial patterns of SLP which force the ASL and coastal wind stress during the transitions.

Population Genetics and Demography Unite Ecology and Evolution.

PubMed

Lowe, Winsor H; Kovach, Ryan P; Allendorf, Fred W

2017-02-01

The interplay of ecology and evolution has been a rich area of research for decades. A surge of interest in this area was catalyzed by the observation that evolution by natural selection can operate at the same contemporary timescales as ecological dynamics. Specifically, recent eco-evolutionary research focuses on how rapid adaptation influences ecology, and vice versa. Evolution by non-adaptive forces also occurs quickly, with ecological consequences, but understanding the full scope of ecology-evolution (eco-evo) interactions requires explicitly addressing population-level processes - genetic and demographic. We show the strong ecological effects of non-adaptive evolutionary forces and, more broadly, the value of population-level research for gaining a mechanistic understanding of eco-evo interactions. The breadth of eco-evolutionary research should expand to incorporate the breadth of evolution itself. Copyright © 2016 Elsevier Ltd. All rights reserved.

Range Environmental Assessment Overland Air Operations, Eglin Air Force Base, Florida

DTIC Science & Technology

2014-11-12

Level AICUZ Air Installation Compatible Use Zones ALANG Alabama Air National Guard ALARNG Alabama Army National Guard ASC Aeronautical Systems Center...7th Special Forces Group (Airborne) (7 SFG): x 2 − Alabama Air National Guard ( ALANG ): x 2 − Other Units: x 2 − 53rd Wing (53 WG): x 1.5...N&P 3 6 CH47 CH-47D 2 4 C23 HS748 1 2 U28A JPATS 2 4 CASA212 HS748 1 2 ALANG UH60 UH60A 4 8 Total for R-2915A 7575 14293 R-2915B AFSOC A10 A

[Nitrous oxide production by the German Armed Forces in the 20th century : History of medicine and pharmacy in the Armed Forces].

PubMed

Kronabel, D B J

2010-03-01

The nitrous oxide production unit of the German Armed Forces was a worldwide unique facility which was only employed in the former main medical depot at Euskirchen (nitrous oxide: medical gas which is now obsolete). The last unit was phased out in 2002 and brought to the main medical depot at Blankenburg. Unfortunately the unit is now no longer in the depot and seems to have disappeared. This article describes the nitrous oxide production process and the use of the production unit which was designed by the Socsil company of Switzerland.

UDAF bioenvironmental noise data handbook. Volume 164: MD-1 heater, duct type, portable

NASA Astrophysics Data System (ADS)

Rau, T. H.

1982-05-01

The MD-1 heater is an electric motor-driven, portable ground heater used primarily for cockpit and cabin temperature control. This report provides measured and extrapolated data defining the bioacoustic environments produced by this unit operating outdoors on a concrete apron at normal rated conditions. Near-field data are reported for 37 locations in a wide variety of physical and psychoacoustic measures: overall and band sound pressure levels, C-weighted and A-weighted sound levels, preferred speech interference level, perceived noise levels, and limiting times for total daily exposure of personnel with and without standard Air Force ear protectors.

USAF bioenvironmental noise data handbook. Volume 162: MD-4MO generator set

NASA Astrophysics Data System (ADS)

Rau, T. H.

1982-05-01

The MD-4MO generator set is an electric motor-driven source of electrical power used primarily for the starting of aircraft, and for ground maintenance. This report provides measured and extrapolated data defining the bioacoustic environments produced by this unit operating outdoors on a concrete apron at a normal rated condition. Near-field data are reported for 37 locations in a wide variety of physical and psychoacoustic measures: overall and band sound pressure levels, C-weighted and A-weighted sound levels, preferred speech interference levels, perceived noise levels, and limiting times for total daily exposure of personnel with and without standard Air Force ear protectors.

United States Air Force Summer Research Program -- 1993. Volume 8. Phillips Laboratory

DTIC Science & Technology

1993-12-01

Research Program Phillips Laboratory Kirtland Air Force Base Albuquerque. New Mexico Sponsored by...Best Available Copy UNITED STATES AIR FORCE SUMMER RESEARCH PROGRAM -- 1993 SUMMER RESEARCH PROGRAM FINAL REPORTS VOLUME 8 PHILLIPS LABORATORY ...Alabama Box 870344 Tuscaloosa, AL 35487-0344 Final Report for: Graduate Student Research Program Phillips Laboratory , Hanscom AFB Sponsored by: Air

32 CFR 154.7 - Criteria for application of security standards.

Code of Federal Regulations, 2012 CFR

2012-07-01

... interests of the United States, or with any person who advocates the use of force or violence to overthrow... unconstitutional means. (c) Advocacy or use of force or violence to overthrow the Government of the United States... force or violence to prevent others from exercising their rights under the Constitution or laws of the U...

32 CFR 154.7 - Criteria for application of security standards.

Code of Federal Regulations, 2010 CFR

2010-07-01

... interests of the United States, or with any person who advocates the use of force or violence to overthrow... unconstitutional means. (c) Advocacy or use of force or violence to overthrow the Government of the United States... force or violence to prevent others from exercising their rights under the Constitution or laws of the U...

32 CFR 154.7 - Criteria for application of security standards.

Code of Federal Regulations, 2013 CFR

2013-07-01

... interests of the United States, or with any person who advocates the use of force or violence to overthrow... unconstitutional means. (c) Advocacy or use of force or violence to overthrow the Government of the United States... force or violence to prevent others from exercising their rights under the Constitution or laws of the U...

32 CFR 154.7 - Criteria for application of security standards.

Code of Federal Regulations, 2011 CFR

2011-07-01

... interests of the United States, or with any person who advocates the use of force or violence to overthrow... unconstitutional means. (c) Advocacy or use of force or violence to overthrow the Government of the United States... force or violence to prevent others from exercising their rights under the Constitution or laws of the U...

32 CFR 154.7 - Criteria for application of security standards.

Code of Federal Regulations, 2014 CFR

2014-07-01

... interests of the United States, or with any person who advocates the use of force or violence to overthrow... unconstitutional means. (c) Advocacy or use of force or violence to overthrow the Government of the United States... force or violence to prevent others from exercising their rights under the Constitution or laws of the U...

The effect of fast and slow motor unit activation on whole-muscle mechanical performance: the size principle may not pose a mechanical paradox.

PubMed

Holt, N C; Wakeling, J M; Biewener, A A

2014-05-22

The output of skeletal muscle can be varied by selectively recruiting different motor units. However, our knowledge of muscle function is largely derived from muscle in which all motor units are activated. This discrepancy may limit our understanding of in vivo muscle function. Hence, this study aimed to characterize the mechanical properties of muscle with different motor unit activation. We determined the isometric properties and isotonic force-velocity relationship of rat plantaris muscles in situ with all of the muscle active, 30% of the muscle containing predominately slower motor units active or 20% of the muscle containing predominately faster motor units active. There was a significant effect of active motor unit type on isometric force rise time (p < 0.001) and the force-velocity relationship (p < 0.001). Surprisingly, force rise time was longer and maximum shortening velocity higher when all motor units were active than when either fast or slow motor units were selectively activated. We propose this is due to the greater relative effects of factors such as series compliance and muscle resistance to shortening during sub-maximal contractions. The findings presented here suggest that recruitment according to the size principle, where slow motor units are activated first and faster ones recruited as demand increases, may not pose a mechanical paradox, as has been previously suggested.

[Medical support of Russian Armed Forces: the results and perspectives].

PubMed

Shappo, V V

2008-01-01

The results of work of the Russian Federation Armed Forces medical service obtained in 2007 were summarized and the main problems of its activities in the current year and the very near future were determined. So the work at defining medical support as a type of Army and Navy support was began. The most important task of medical service in 2008 is realization of the Armed Forces medical support conception and goal-oriented program "The improvement of Russian Federation Armed Forces medical support in 2008-2012", the formation of two-level system of personnel's medical support. During the task realization the medical units and institutions are reorganized into federal state institutions. The RF DM Main Military Medical Headquarters works at significant improvement of war and military service veterans' medical attendance. The departmental program "Development of material and technical basis of military medical institutions for 2001-2010" is successfully realized. The measures to optimize the assignment of graduates from military medical higher schools are carried out. The tasks to improve the research work were outlined. The new principles of organization of military medical service control and work will be based on centralization of planning and decentralization of decision implementation, the possibility of military medical units to carry it out taking into account the common intention, safe feedback in order to make the work of army and navy medical specialists more effective in any conditions.

Effects of barbell deadlift training on submaximal motor unit firing rates for the vastus lateralis and rectus femoris.

PubMed

Stock, Matt S; Thompson, Brennan J

2014-01-01

Previous investigations that have studied motor unit firing rates following strength training have been limited to small muscles, isometric training, or interventions involving exercise machines. We examined the effects of ten weeks of supervised barbell deadlift training on motor unit firing rates for the vastus lateralis and rectus femoris during a 50% maximum voluntary contraction (MVC) assessment. Twenty-four previously untrained men (mean age  = 24 years) were randomly assigned to training (n = 15) or control (n = 9) groups. Before and following the intervention, the subjects performed isometric testing of the right knee extensors while bipolar surface electromyographic signals were detected from the two muscles. The signals were decomposed into their constituent motor unit action potential trains, and motor units that demonstrated accuracy levels less than 92.0% were not considered for analysis. One thousand eight hundred ninety-two and 2,013 motor units were examined for the vastus lateralis and rectus femoris, respectively. Regression analyses were used to determine the linear slope coefficients (pulses per second [pps]/% MVC) and y-intercepts (pps) of the mean firing rate and firing rate at recruitment versus recruitment threshold relationships. Deadlift training significantly improved knee extensor MVC force (Cohen's d = .70), but did not influence force steadiness. Training had no influence on the slopes and y-intercepts for the mean firing rate and firing rate at recruitment versus recruitment threshold relationships. In agreement with previous cross-sectional comparisons and randomized control trials, our findings do not support the notion that strength training affects the submaximal control of motor units.

Contractual Duration and Investment Incentives: Evidence from Large Scale Production Units in China

NASA Astrophysics Data System (ADS)

Li, Fang; Feng, Shuyi; D'Haese, Marijke; Lu, Hualiang; Qu, Futian

2017-04-01

Large Scale Production Units have become important forces in the supply of agricultural commodities and agricultural modernization in China. Contractual duration in farmland transfer to Large Scale Production Units can be considered to reflect land tenure security. Theoretically, long-term tenancy contracts can encourage Large Scale Production Units to increase long-term investments by ensuring land rights stability or favoring access to credit. Using a unique Large Scale Production Units- and plot-level field survey dataset from Jiangsu and Jiangxi Province, this study aims to examine the effect of contractual duration on Large Scale Production Units' soil conservation behaviours. IV method is applied to take into account the endogeneity of contractual duration and unobserved household heterogeneity. Results indicate that farmland transfer contract duration significantly and positively affects land-improving investments. Policies aimed at improving transaction platforms and intermediary organizations in farmland transfer to facilitate Large Scale Production Units to access farmland with long-term tenancy contracts may therefore play an important role in improving soil quality and land productivity.

[Psychiatric security units in Norway. Patients and activity].

PubMed

Linaker, O M; Thoresen, R; Figenschou, L; Sølvberg, H; Refsnes, U; Jakobsen, D

1994-05-20

The authors briefly discuss past and present reasons for the psychiatric security unit system in Norway. They describe the patients in these units at the beginning of 1993 (N = 123). Of these patients, 16% were females, 78% had a main diagnosis of schizophrenia, and 12% were admitted because of personality disorders. Physical restraints had been used for 25%, pharmacological restraints for 17%, and forced pharmacological treatment had been necessary for 26% of the patients during the last six months. There were high rates of behaviour problems related to criminality, abuse, violence and auto-aggression. Nearly all the patients were committed involuntarily, and additional legal restrictions were imposed for one third of them. The majority (63%) of the patients had been in security units for more than one year. The highest levels of security within the security unit system were used for those with the most serious criminality or behaviour problems prior to admission.

A prospective study of carpal tunnel syndrome: workplace and individual risk factors.

PubMed

Burt, Susan; Deddens, James A; Crombie, Ken; Jin, Yan; Wurzelbacher, Steve; Ramsey, Jessica

2013-08-01

To quantify the risk for carpal tunnel syndrome (CTS) from workplace physical factors, particularly hand activity level and forceful exertion, while taking into account individual factors including age, gender, body mass index (BMI), and pre-existing medical conditions. Three healthcare and manufacturing workplaces were selected for inclusion on the basis of range of exposure to hand activity level and forceful exertion represented by their jobs. Each study participant's job tasks were observed and evaluated onsite and videotaped for further analysis, including frequency and duration of exertion and postural deviation. Individual health assessment entailed electrodiagnostic testing of median and ulnar nerves, physical examination and questionnaires at baseline with annual follow-up for 2 years. The incidence of dominant hand CTS during the study was 5.11 per 100 person-years (29 cases). Adjusted HRs for dominant hand CTS were as follows: working with forceful exertion ≥ 20% but <60% of the time: 2.83 (1.18, 6.79) and ≥ 60% of the time vs <20%: 19.57 (5.96, 64.24), BMI ≥ 30 kg/m(2) (obesity): 3.19 (1.28, 7.98). The American Conference for Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV) for hand activity level also predicted CTS, HR=1.40 (1.11, 1.78) for each unit increase in the TLV ratio, controlling for obesity and job strain. Workplace and individual risk factors both contribute to the risk for CTS. Time spent in forceful exertion can be a greater risk for CTS than obesity if the job exposure is high. Preventive workplace efforts should target forceful exertions.

Lumbar extensor muscle force control is associated with disability in people with chronic low back pain.

PubMed

Pranata, Adrian; Perraton, Luke; El-Ansary, Doa; Clark, Ross; Fortin, Karine; Dettmann, Tim; Brandham, Robert; Bryant, Adam

2017-07-01

The ability to control lumbar extensor force output is necessary for daily activities. However, it is unknown whether this ability is impaired in chronic low back pain patients. Similarly, it is unknown whether lumbar extensor force control is related to the disability levels of chronic low back pain patients. Thirty-three chronic low back pain and 20 healthy people performed lumbar extension force-matching task where they increased and decreased their force output to match a variable target force within 20%-50% maximal voluntary isometric contraction. Force control was quantified as the root-mean-square-error between participants' force output and target force across the entire, during the increasing and decreasing portions of the force curve. Within- and between-group differences in force-matching error and the relationship between back pain group's force-matching results and their Oswestry Disability Index scores were assessed using ANCOVA and linear regression respectively. Back pain group demonstrated more overall force-matching error (mean difference=1.60 [0.78, 2.43], P<0.01) and more force-matching error while increasing force output (mean difference=2.19 [1.01, 3.37], P<0.01) than control group. The back pain group demonstrated more force-matching error while increasing than decreasing force output (mean difference=1.74, P<0.001, 95%CI [0.87, 2.61]). A unit increase in force-matching error while decreasing force output is associated with a 47% increase in Oswestry score in back pain group (R 2 =0.19, P=0.006). Lumbar extensor muscle force control is compromised in chronic low back pain patients. Force-matching error predicts disability, confirming the validity of our force control protocol for chronic low back pain patients. Copyright © 2017 Elsevier Ltd. All rights reserved.

U. S. Naval Forces, Vietnam Monthly Historical Supplement for March 1968

DTIC Science & Technology

1968-08-29

Force BARKER units. On the 30th PCFs 21 and 22 provided blocking patrols for a sweep by units of the U.S. Army 1st Cavalry Division near the mouth of...large junks transiting at night on a canal in the Dung Island complex near the mouth of the Bassac -. River. Two PBRs from Task Unit I16.1.2 and a...the con- voy approached tle mouth of the Hien Giang River, it was ambushed by Viet Cong and North Vietnamese forces who were entrenched in heavily

Korea to Kalimantan and Beyond: The Employment of United States Army Forces in Military Civic Action in the Pacific Command Area of Responsibility

DTIC Science & Technology

1990-04-09

may not be reeased (or open ibkou eanb t it his been deared by de appropriate military servlc or govemlient mency. Co KOREA TO KALIMANTAN AND BEYOND... Kalimantan and Beyond: The Employment of United States Army Forces Individual Study in Military Civic Action in the Pacific 6. PERFORMING ORG. REPORTN MBER...PROGRAM PAPER KOREA TO KALIMANTAN AND BEYOND: THE EMPLOYMENT OF UNITED STATES ARMY FORCES IN MILITARY CIVIC ACTION IN THE PACIFIC COMMAND AREA OF

Invoking Arbitrary Units Is Not a Solution to the Problem of Quantification in the Social Sciences

ERIC Educational Resources Information Center

Barrett, Paul

2011-01-01

The article by Stephen Humphry (this issue) is a technical tour de force. At one level, the author marvels at the ingenuity and sophisticated logic and argument on display. This is impressive work and thinking whichever way one looks at it. However, after twice re-reading the manuscript, the same question arises on the author's mind: What exactly…

Augmented Reality at the Tactical and Operational Levels of War

DTIC Science & Technology

2015-10-24

benefits and challenges their personnel will experience once AR systems are fully adopted. This paper will explain these benefits and challenges as...develop, procure, and integrate systems it believes will benefit its tactical combat units and operational leaders. Ultimately, as the capabilities of...friendly forces, can also help to prevent collateral damage and civilian casualties. Beyond the immediate life-and-death benefits at the tactical

A Senior High School Social Studies Unit on Africa South of the Sahara. World History Series, Bulletin No. 252.

ERIC Educational Resources Information Center

Kelly, Harry; And Others

This secondary level curriculum guide provides a program and identifies materials for the study of the history and culture of Africa south of the Sahara. The primary purpose of this course is to stimulate thought and to encourage students to make valid generalizations and intelligent assessments of the forces and events that have and are shaping…

An Analysis of the United States Air Force Energy Savings Performance Contracts

DTIC Science & Technology

2007-12-01

key element of the ESPC system. Chapter IV uses the standard contracting processes to review the USAF implementations of strategic purchasing with...process and each level facilitates regionalization, which is the current implementation method of strategic purchasing for energy service management...the existing regulations that are inconsistent with the ESPC intent , and 3) to formulate substitute regulations consistent with laws governing Federal

Life Cycle Costing: A Working Level Approach

DTIC Science & Technology

1981-06-01

Effects Analysis ( FMEA ) ...... ................ .. 59 Logistics Performance Factors (LPFs) 60 Planning the Use of Life Cycle Cost in the Demonstration...form. Failure Mode and Effects Analysis ( FMEA ). Description. FMEA is a technique that attempts to improve the design of any particular unit. The FMEA ...failure modes and also eliminate extra parts or ones that are used to achieve more performance than is necessary (16:5-14]. Advantages. FMEA forces

Living History: Pioneering Bandswomen of the United States Air Force

ERIC Educational Resources Information Center

Nichols, Jeananne

2015-01-01

This narrative describes two United States Air Force bandswomen whose combined careers span the past sixty years. Cornetist Martha (Martye) Jean Awkerman joined the U.S. Women in the Air Force (WAF) Band in 1955. She served the WAF band as cornet soloist and principal trumpet until the band was disbanded in 1961. In 1983, tubist Jan Duga joined…

NEON VISUALIZATION ENVIRONMENT

DTIC Science & Technology

2017-07-28

STINFO COPY AIR FORCE RESEARCH LABORATORY INFORMATION DIRECTORATE AFRL-RI-RS-TR-2017-143  UNITED STATES AIR FORCE  ROME, NY 13441 AIR FORCE...report is available to the general public, including foreign nationals. Copies may be obtained from the Defense Technical Information Center (DTIC) (http...FOR THE CHIEF ENGINEER: / S / / S / PETER A. JEDRYSIK JULIE BRICHACEK Work Unit Manager Chief, Information Systems Division Information

A Historical Analysis of Basic Air Force Doctrine Education within the United States States Air Force Air Command and Staff College, 1947-1987.

DTIC Science & Technology

1987-09-01

doctrine, especially joint doctrine. Because of this we make mistakes. I believe that the Air Force needs to develop a formal doctrinallo education...jresenteo arguments for all three points of view, but ne was particularly critical of tne educacional system within tae United States military. He said tnat

Integrating Partner Nations into Coalition Operations

DTIC Science & Technology

2006-01-01

of United Nations (UN) Security Council Resolu- tion 1529, Chile , Canada, France, and the United States established a multinational force...of restabi- lization. Chile continues to deploy forces as a member of the UN Stabilization Force Haiti (MINUSTAH), led by Brazil and comprised...supporting a tailored exercise and theater security cooperation program that has encouraged partners such as Chile , Brazil, and El Salvador to develop

Tomorrow. The Report of the Task Force for the Study of Chemistry Education in the United States.

ERIC Educational Resources Information Center

American Chemical Society, Washington, DC.

An American Chemical Society (ACS) task force was charged to examine the state of chemistry education in the United States and to make recommendations in light of its findings. This document presents the task force's report and 39 major (and also secondary) recommendations. These recommendations, with accompanying discussions, focus on: (1)…

Organic sensitizers featuring thiophene derivative based donors with improved stability and photovoltaic performance.

PubMed

Miao, Kai; Liang, Mao; Wang, Zhihui; Zhang, Chunyao; Sun, Zhe; Xue, Song

2017-01-18

Thiophene derivatives, including thieno[3,2-b][1]benzothiophene (TBT), benzo[b]thiophene (BT), 2-phenylthieno[3,2-b]thiophene (PTT) and 2-phenylthiophene (PT), have been introduced as donors for the construction of triarylamine organic dyes (M52, M53, M56, M57 and M52A). The absorption, electrochemical and photovoltaic properties as well as the stabilities of these dyes are systematically investigated and compared with the reference dye (M55), whose donor is composed of the hexyloxybenzene (HOB) unit. It is found that introducing the TBT, BT, PTT or PT donors positively shifted the HOMO and LUMO levels of the organic dyes, providing a larger driving force for regeneration and reducing the energy loss for electron injection. In addition, we found that M52, which contains the TBT unit, exhibited better photovoltaic performance and photostability as compared to the reference dye. In contrast, M53 displayed the lowest efficiency and stability of these dyes, indicating that the BT unit is not a good building block for donors. Interestingly, upon the incorporation of the mixed donor (TBT-HOB), M52A achieved a desirable driving force for regeneration without a loss in light absorption, thus resulting in a further improved photovoltaic performance with respect to that of M52. This work demonstrates that introducing donors based on thiophene derivatives is a good strategy for tuning the energy levels and thereby enhancing the efficiency of the resulting devices.

Auxiliary propulsion system flight package

NASA Technical Reports Server (NTRS)

Collett, C. R.

1987-01-01

Hughes Aircraft Company developed qualified and integrated flight, a flight test Ion Auxiliary Propulsion System (IAPS), on an Air Force technology satellite. The IAPS Flight Package consists of two identical Thruster Subsystems and a Diagnostic Subsystem. Each thruster subsystem (TSS) is comprised of an 8-cm ion Thruster-Gimbal-Beam Shield Unit (TGBSU); Power Electronics Unit; Digital Controller and Interface Unit (DCIU); and Propellant Tank, Valve and Feed Unit (PTVFU) plus the requisite cables. The Diagnostic Subsystem (DSS) includes four types of sensors for measuring the effect of the ion thrusters on the spacecraft and the surrounding plasma. Flight qualifications of IAPS, prior to installation on the spacecraft, consisted of performance, vibration and thermal-vacuum testing at the unit level, and thermal-vacuum testing at the subsystem level. Mutual compatibility between IAPS and the host spacecraft was demonstrated during a series of performance and environmental tests after the IAPS Flight Package was installed on the spacecraft. After a spacecraft acoustic test, performance of the ion thrusters was reverified by removing the TGBSUs for a thorough performance test at Hughes Research Laboratories (HRL). The TGBSUs were then reinstalled on the spacecraft. The IAPS Flight Package is ready for flight testing when Shuttle flights are resumed.

Community hoarding task forces: a comparative case study of five task forces in the United States.

PubMed

Bratiotis, Christiana

2013-05-01

During the past decade, many community task forces have formed to address hoarding problems that come to public attention. Such task forces provide a societal-level intervention to assist people with the most severe cases of hoarding, who do not voluntarily seek or want help for their hoarding behaviour. This qualitative study of five U.S. hoarding task forces included sites selected for their diversity of purpose, approaches to hoarding intervention and community geography, composition and resources. Data were collected during the period of September 2007-March 2008. The case study methodology used multiple forms of data, including semi-structured interviews, analysis of documents, small group interviews and investigator observation. This study captured the perspectives of public and private sector service providers such as mental health, housing, social service, public health agencies and community enforcement organisations (fire, police, legal, animal control) to examine how task forces organise and operate and the emerging practice and policy changes. Study findings suggest that structural factors (e.g. leadership, purpose, funding and membership) impact hoarding task force viability, that participation on a task force influences practice and policy decisions about hoarding, and that social work can expand its role in task force leadership. Task forces may be a mechanism for improving community policies about hoarding and mechanisms for addressing other social problems across multiple sectors. © 2012 Blackwell Publishing Ltd.

Lung segmentation from HRCT using united geometric active contours

NASA Astrophysics Data System (ADS)

Liu, Junwei; Li, Chuanfu; Xiong, Jin; Feng, Huanqing

2007-12-01

Accurate lung segmentation from high resolution CT images is a challenging task due to various detail tracheal structures, missing boundary segments and complex lung anatomy. One popular method is based on gray-level threshold, however its results are usually rough. A united geometric active contours model based on level set is proposed for lung segmentation in this paper. Particularly, this method combines local boundary information and region statistical-based model synchronously: 1) Boundary term ensures the integrality of lung tissue.2) Region term makes the level set function evolve with global characteristic and independent on initial settings. A penalizing energy term is introduced into the model, which forces the level set function evolving without re-initialization. The method is found to be much more efficient in lung segmentation than other methods that are only based on boundary or region. Results are shown by 3D lung surface reconstruction, which indicates that the method will play an important role in the design of computer-aided diagnostic (CAD) system.

Dealing with time-varying recruitment and length in Hill-type muscle models.

PubMed

Hamouda, Ahmed; Kenney, Laurence; Howard, David

2016-10-03

Hill-type muscle models are often used in muscle simulation studies and also in the design and virtual prototyping of functional electrical stimulation systems. These models have to behave in a sufficiently realistic manner when recruitment level and contractile element (CE) length change continuously. For this reason, most previous models have used instantaneous CE length in the muscle׳s force vs. length (F-L) relationship, but thereby neglect the instability problem on the descending limb (i.e. region of negative slope) of the F-L relationship. Ideally CE length at initial recruitment should be used but this requires a multiple-motor-unit muscle model to properly account for different motor-units having different initial lengths when recruited. None of the multiple-motor-unit models reported in the literature have used initial CE length in the muscle׳s F-L relationship, thereby also neglecting the descending limb instability problem. To address the problem of muscle modelling for continuously varying recruitment and length, and hence different values of initial CE length for different motor-units, a new multiple-motor-unit muscle model is presented which considers the muscle to comprise 1000 individual Hill-type virtual motor-units, which determine the total isometric force. Other parts of the model (F-V relationship and passive elements) are not dependent on the initial CE length and, therefore, they are implemented for the muscle as a whole rather than for the individual motor-units. The results demonstrate the potential errors introduced by using a single-motor-unit model and also the instantaneous CE length in the F-L relationship, both of which are common in FES control studies. Copyright © 2016 Elsevier Ltd. All rights reserved.

Motor unit recruitment and firing rate in medial gastrocnemius muscles during external perturbations in standing in humans.

PubMed

Pollock, C L; Ivanova, T D; Hunt, M A; Garland, S J

2014-10-01

There is limited investigation of the interaction between motor unit recruitment and rate coding for modulating force during standing or responding to external perturbations. Fifty-seven motor units were recorded from the medial gastrocnemius muscle with intramuscular electrodes in response to external perturbations in standing. Anteriorly directed perturbations were generated by applying loads in 0.45-kg increments at the pelvis every 25-40 s until 2.25 kg was maintained. Motor unit firing rate was calculated for the initial recruitment load and all subsequent loads during two epochs: 1) dynamic response to perturbation directly following each load drop and 2) maintenance of steady state between perturbations. Joint kinematics and surface electromyography (EMG) from lower extremities and force platform measurements were assessed. Application of the external loads resulted in a significant forward progression of the anterior-posterior center of pressure (AP COP) that was accompanied by modest changes in joint angles (<3°). Surface EMG increased more in medial gastrocnemius than in the other recorded muscles. At initial recruitment, motor unit firing rate immediately after the load drop was significantly lower than during subsequent load drops or during the steady state at the same load. There was a modest increase in motor unit firing rate immediately after the load drop on subsequent load drops associated with regaining balance. There was no effect of maintaining balance with increased load and forward progression of the AP COP on steady-state motor unit firing rate. The medial gastrocnemius utilized primarily motor unit recruitment to achieve the increased levels of activation necessary to maintain standing in the presence of external loads. Copyright © 2014 the American Physiological Society.

Space Separatism: Degree of Differentiation

DTIC Science & Technology

2014-12-01

Separate Service” (Norfolk, VA: Joint Forces Staff College, 6 September 2002); MAJ William S. Moncrief , “Building a United States Space Force,” Army Space...unclassified b. ABSTRACT unclassified c . THIS PAGE unclassified Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 November–December 2014 Air...FY14_Green_Book.pdf. 32. Story, “Separate Space Force,” 2–5. 33. Moncrief , “Building a United States Space Force,” 34–38. 34. DODD 3100.10, Space Policy, 3. 35. Lt

Determining the Probability of Violating Upper-Level Wind Constraints for the Launch of Minuteman Ill Ballistic Missiles At Vandenberg Air Force Base

NASA Technical Reports Server (NTRS)

Shafer, Jaclyn A.; Brock, Tyler M.

2013-01-01

The 30th Operational Support Squadron Weather Flight (30 OSSWF) provides comprehensive weather services to the space program at Vandenberg Air Force Base (VAFB) in California. One of their responsibilities is to monitor upper-level winds to ensure safe launch operations of the Minuteman Ill ballistic missile. The 30 OSSWF requested the Applied Meteorology Unit (AMU) analyze VAFB sounding data to determine the probability of violating (PoV) upper-level thresholds for wind speed and shear constraints specific to this launch vehicle, and to develop a graphical user interface (GUI) that will calculate the PoV of each constraint on the day of launch. The AMU suggested also including forecast sounding data from the Rapid Refresh (RAP) model. This would provide further insight for the launch weather officers (LWOs) when determining if a wind constraint violation will occur over the next few hours, and help to improve the overall upper winds forecast on launch day.

Instrument for controlling the application of mechanical loads to biological and bicompatible test subjects

DOEpatents

Lintilhac, Phillip M.; Vesecky, Thompson B.

1995-01-01

Apparatus and methods are disclosed facilitating the application of forces and measurement of dimensions of a test subject. In one arrangement the test subject is coupled to a forcing frame and controlled forces applied thereto. Force applied to the test subject is measured and controlled. A dimensional characteristic of the test subject, such as growth, is measured by a linear variable differential transformer. The growth measurement data can be used to control the force applied. The transducer module receives force and dimensional data from the forcing frame. The transducer module is a separate, microprocessor-based unit that communicates the test data to a controller unit that controls the application of force to the test subject and receives the test data from the transducer module for force control, storage, and/or communication to the user.

Instrument for controlling the application of mechanical loads to biological and bicompatible test subjects

DOEpatents

Lintilhac, P.M.; Vesecky, T.B.

1995-09-19

An apparatus and methods are disclosed facilitating the application of forces and measurement of dimensions of a test subject. In one arrangement the test subject is coupled to a forcing frame and controlled forces applied thereto. Force applied to the test subject is measured and controlled. A dimensional characteristic of the test subject, such as growth, is measured by a linear variable differential transformer. The growth measurement data can be used to control the force applied. The transducer module receives force and dimensional data from the forcing frame. The transducer module is a separate, microprocessor-based unit that communicates the test data to a controller unit that controls the application of force to the test subject and receives the test data from the transducer module for force control, storage, and/or communication to the user. 8 figs.

Viscous/Inviscid Interaction Analysis of the Aerodynamic Performance of the NACA 65-213 Airfoil.

DTIC Science & Technology

1987-03-01

flows . The principal forces that act on the body are those which act directly on the mass of the fluid element, the bodi’ forces , and those which act...shall again consider a 2-D flow , as indicated in Figure.2-. The resultant force in the x- direction, for one unit length in z is F= ph.r~u + a(𔃼.10...x,+.a. Where fx is the body force per-unit mass in the x direction. The most conmmon body force for the flow fields is that of gravity. Equation 2.10

A Physiologically Based, Multi-Scale Model of Skeletal Muscle Structure and Function

PubMed Central

Röhrle, O.; Davidson, J. B.; Pullan, A. J.

2012-01-01

Models of skeletal muscle can be classified as phenomenological or biophysical. Phenomenological models predict the muscle’s response to a specified input based on experimental measurements. Prominent phenomenological models are the Hill-type muscle models, which have been incorporated into rigid-body modeling frameworks, and three-dimensional continuum-mechanical models. Biophysically based models attempt to predict the muscle’s response as emerging from the underlying physiology of the system. In this contribution, the conventional biophysically based modeling methodology is extended to include several structural and functional characteristics of skeletal muscle. The result is a physiologically based, multi-scale skeletal muscle finite element model that is capable of representing detailed, geometrical descriptions of skeletal muscle fibers and their grouping. Together with a well-established model of motor-unit recruitment, the electro-physiological behavior of single muscle fibers within motor units is computed and linked to a continuum-mechanical constitutive law. The bridging between the cellular level and the organ level has been achieved via a multi-scale constitutive law and homogenization. The effect of homogenization has been investigated by varying the number of embedded skeletal muscle fibers and/or motor units and computing the resulting exerted muscle forces while applying the same excitatory input. All simulations were conducted using an anatomically realistic finite element model of the tibialis anterior muscle. Given the fact that the underlying electro-physiological cellular muscle model is capable of modeling metabolic fatigue effects such as potassium accumulation in the T-tubular space and inorganic phosphate build-up, the proposed framework provides a novel simulation-based way to investigate muscle behavior ranging from motor-unit recruitment to force generation and fatigue. PMID:22993509

Experimental Study of Reciprocating Friction between Rape Stalk and Bionic Nonsmooth Surface Units

PubMed Central

Ma, Zheng; Li, Yaoming; Xu, Lizhang

2015-01-01

Background. China is the largest producer of rape oilseed in the world; however, the mechanization level of rape harvest is relatively low, because rape materials easily adhere to the cleaning screens of combine harvesters, resulting in significant cleaning losses. Previous studies have shown that bionic nonsmooth surface cleaning screens restrain the adhesion of rape materials, but the underlying mechanisms remain unclear. Objective. The reciprocating friction between rape stalk and bionic nonsmooth metal surface was examined. Methods. The short-time Fourier transform method was used to discriminate the stable phase of friction signals and the stick-lag distance was defined to analyze the stable reciprocating friction in a phase diagram. Results. The reciprocating friction between rape stalk and metal surface is a typical stick-slip friction, and the bionic nonsmooth metal surfaces with concave or convex units reduced friction force with increasing reciprocating frequency. The results also showed that the stick-lag distance of convex surface increased with reciprocating frequency, which indicated that convex surface reduces friction force more efficiently. Conclusions. We suggest that bionic nonsmooth surface cleaning screens, especially with convex units, restrain the adhesion of rape materials more efficiently compared to the smooth surface cleaning screens. PMID:27034611

Programmatic Environmental Assessment for Base General Plan Development, Schriever Air Force Base, Colorado

DTIC Science & Technology

2012-06-01

will not involve an element of high risk or uncertainty on the human environment, and its effects on the quality of the human environment are not...Information System HAPs Hazardous air pollutants HAZMAT Hazardous Material HVAC heating, ventilation , and air conditioning HUD U.S. Housing and...Engineers USAF Unites States Air Force USC United States Code USEPA United States Environmental Protection Agency USFWS United States Fish and Wildlife

Sensitivity analysis of machine-learning models of hydrologic time series

NASA Astrophysics Data System (ADS)

O'Reilly, A. M.

2017-12-01

Sensitivity analysis traditionally has been applied to assessing model response to perturbations in model parameters, where the parameters are those model input variables adjusted during calibration. Unlike physics-based models where parameters represent real phenomena, the equivalent of parameters for machine-learning models are simply mathematical "knobs" that are automatically adjusted during training/testing/verification procedures. Thus the challenge of extracting knowledge of hydrologic system functionality from machine-learning models lies in their very nature, leading to the label "black box." Sensitivity analysis of the forcing-response behavior of machine-learning models, however, can provide understanding of how the physical phenomena represented by model inputs affect the physical phenomena represented by model outputs.As part of a previous study, hybrid spectral-decomposition artificial neural network (ANN) models were developed to simulate the observed behavior of hydrologic response contained in multidecadal datasets of lake water level, groundwater level, and spring flow. Model inputs used moving window averages (MWA) to represent various frequencies and frequency-band components of time series of rainfall and groundwater use. Using these forcing time series, the MWA-ANN models were trained to predict time series of lake water level, groundwater level, and spring flow at 51 sites in central Florida, USA. A time series of sensitivities for each MWA-ANN model was produced by perturbing forcing time-series and computing the change in response time-series per unit change in perturbation. Variations in forcing-response sensitivities are evident between types (lake, groundwater level, or spring), spatially (among sites of the same type), and temporally. Two generally common characteristics among sites are more uniform sensitivities to rainfall over time and notable increases in sensitivities to groundwater usage during significant drought periods.

The Global Positioning System: Theory and operation

NASA Astrophysics Data System (ADS)

Tucker, Lester Plunkett

Scope and method of study. The purpose of this study is to document the theory, development, and training needs of the United States Global Positioning System for the United States Air Force. This subject area had very little information and to assess the United States Air Force training needs required an investigation into existing training accomplished on the Global Positioning System. The United States Air Force has only one place to obtain the data at Headquarters Air Education and Training Command. Findings and conclusion. The United States Air Force, at the time of this study, does not have a theory and operations course dealing with the newest technology advancement in world navigation. Although this new technology is being provided on aircraft in the form of new navigation hardware, no official course of study is provided by the United States Air Force to it's pilots and navigators dealing with theory and operation. Based on the latest reports dealing with the Global Positioning System, a course on the Global Positioning System was developed in the Instructional Systems Design format to provide background information and understanding of this new technology. Readers of this study must be aware that the information contained in this study is very dynamic. Technology is advancing so fast in this area that it might make this information obsolete in a short amount of time.

Contribution from motor unit firing adaptations and muscle co-activation during fatigue.

PubMed

Contessa, Paola; Letizi, John; De Luca, Gianluca; Kline, Joshua C

2018-03-14

The control of motor unit firing behavior during fatigue is still debated in the literature. Most studies agree that the central nervous system increases the excitation to the motoneuron pool to compensate for decreased force contributions of individual motor units and sustain muscle force output during fatigue. However, some studies claim that motor units may decrease their firing rates despite increased excitation, contradicting the direct relationship between firing rates and excitation that governs the voluntary control of motor units. To investigate whether the control of motor units in fact changes with fatigue, we measured motor unit firing behavior during repeated contractions of the first dorsal interosseous (FDI) muscle while concurrently monitoring the activation of surrounding muscles - including the flexor carpi radialis, extensor carpi radialis, and pronator teres. Across all subjects, we observed an overall increase in FDI activation and motor unit firing rates by the end of the fatigue task. However, in some subjects we observed increases in FDI activation and motor unit firing rates only during the initial phase of the fatigue task, followed by subsequent decreases during the late phase of the fatigue task while the co-activation of surrounding muscles increased. These findings indicate that the strategy for sustaining force output may occasionally change leading to increases in the relative activation of surrounding muscles while the excitation to the fatiguing muscle decreases. Importantly, irrespective of changes in the strategy for sustaining force output, the control properties regulating motor unit firing behavior remain unchanged during fatigue.

Superfund record of decision amendment (EPA Region 10): USAF Eielson Air Force Base, Operable Units 3, 4, and 5, Fairbanks North Star Borough, AK, September 29, 1998

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

This decision document presents the amended remedial action for Operable Units 3, 4, and 5 (OUs 3, 4, and 5) at Eielson Air Force Base (AFB). This decision is based on the Administrative Record for OU 3, 4, and 5, updated in July 1998, to include new information generated since the original Record of Decision was signed on 30 September 1995 (PB95-964618). This amendment applies to OU3 site DP44 (Battery Shop Leach Field Building), OU4 sites SS35 (Asphalt Mixing Area) and ST58 (Old Quartermaster Service Station), and OU5 sites LF03/FT09 (Current Inactive Base Landfill/Fire Training Area). Through new information, contaminantmore » levels than interpreted prior to signing the original ROD document. Proper enforcement of Institutional Controls (IC`s) at all sites will be effective in controlling and restricting access to contaminated media at the sites remediation goals are achieved.« less

An analysis of post-traumatic stress symptoms in United States Air Force drone operators.

PubMed

Chappelle, Wayne; Goodman, Tanya; Reardon, Laura; Thompson, William

2014-06-01

Remotely piloted aircraft (RPA), commonly referred to as "drones," have emerged over the past decade as an innovative warfighting tool. Given there is a paucity of empirical research assessing drone operators, the purpose of this study was to assess for the prevalence of PTSD symptoms among this cohort. Of the 1084 United States Air Force (USAF) drone operators that participated, a total of 4.3% endorsed a pattern of symptoms of moderate to extreme level of severity meeting criteria outlined in the Diagnostic and Statistical Manual of Mental Disorders-4th edition. The incidence of PTSD among USAF drone operators in this study was lower than rates of PTSD (10-18%) among military personnel returning from deployment but higher than incidence rates (less than 1%) of USAF drone operators reported in electronic medical records. Although low PTSD rates may be promising, limitations to this study are discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

United States Air Force Summer Research Program -- 1992 High School Apprenticeship Program (HSAP) Reports. Volume 13. Phillips Laboratory

DTIC Science & Technology

1992-01-01

Research Program Phillips Laboratory I4oJ A*6Iv4 Sponsored by: Air Force Office of Scientific Research Kirtland Air ...UNITED STATES AIR FORCE SUMMER RESEARCH PROGki"A -- 1992 HIGH SCHOOL APPRENTICESHIP PROGRAM (HSAP) REPORTS VOLUME 13 (t PHILLIPS LABORATORY . RESEARCH ...Arlington High School Final Report for: Summer Research Program Geophysics Directorate Phillips Laboratory

75 FR 3331 - Ordering the Selected Reserve and Certain Individual Ready Reserve Members of the Armed Forces to...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-21

... Members of the Armed Forces to Active Duty By the authority vested in me as President by the Constitution... States Code, I hereby determine that it is necessary to augment the active Armed Forces of the United... respective jurisdictions, to order to active duty any units, and any individual members not assigned to a...

Hydrogeology at Air Force Plant 4 and vicinity and water quality of the Paluxy Aquifer, Fort Worth, Texas

USGS Publications Warehouse

Kuniansky, Eve L.; Jones, Sonya A.; Brock, Robert D.; Williams, M.D.

1996-01-01

Ground water in the surficial terrace alluvial aquifer is contaminated at Air Force Plant 4, Fort Worth, Texas, and at the adjacent Naval Air Station. Some of the contaminated water has leaked from the terrace alluvial aquifer to an uppermost interval of the Paluxy Formation (the Paluxy "upper sand") beneath the east parking lot, east of the assembly building, and to the upper and middle zones of the Paluxy aquifer near Bomber Road, west of the assembly building. Citizens are concerned that contaminants from the plant, principally trichloroethylene and chromium might enter nearby municipal and domestic wells that pump water from the middle and lower zones of the Paluxy aquifer. Geologic formations that crop out in the study area, from oldest to youngest, are the Paluxy Formation (aquifer), Walnut Formation (confining unit), and Goodland Limestone (confining unit). Beneath the Paluxy Formation is the Glen Rose Formation (confining unit) and Twin Mountains Formation (aquifer). The terrace alluvial deposits overlie these Cretaceous rocks. The terrace alluvial aquifer, which is not used for municipal water supply, is separated from the Paluxy aquifer by the Goodland-Walnut confining unit. The confining unit restricts the flow of ground water between these aquifers in most places; however, downward leakage to the Paluxy aquifer might occur through the "window," where the confining unit is thin or absent. The Paluxy aquifer is divided into upper, middle, and lower zones. The Paluxy "upper sand" underlying the "window" is an apparently isolated, mostly unsaturated, sandy lens within the uppermost part of the upper zone. The Paluxy aquifer is recharged by leakage from Lake Worth and by precipitation on the outcrop area. Discharge from the aquifer primarily occurs as pumpage from municipal and domestic wells. The Paluxy aquifer is separated from the underlying Twin Mountains aquifer by the Glen Rose confining unit. Water-level maps indicate that (1) ground water in the terrace alluvial aquifer appears to flow outward, away from Air Force Plant 4; (2) a ground-water mound, possibly caused by downward leakage from the terrace alluvial aquifer, is present in the Paluxy "upper sand" beneath the "window;" and (3) lateral ground-water flow in regionally extensive parts of the Paluxy aquifer is from west to east-southeast. Trichloroethylene concentrations at Air Force Plant 4 have ranged from about 10,000 to about 100,000 micrograms per liter in the terrace alluvial aquifer, from 8,000 to 11,000 micrograms per liter in the Paluxy "upper sand," and from 2 to 50 micrograms per liter in the upper and middle zones of the Paluxy aquifer. Chromium concentrations at Air Force Plant 4 have ranged from 0 to 629 micrograms per liter in the terrace alluvial aquifer. The seven municipal wells mostly west and south of Air Force Plant 4 are not along a flowpath for leakage of contaminants from the plant because ground-water flow in the Paluxy aquifer is toward the east-southeast. Furthermore, trichloroethylene was not detected in any of these wells in 1993 when all were sampled for water quality. The results of water-quality sampling at 10 domestic wells northwest of the Air Force Plant 4 during April 1993 and April 1995 indicated that neither trichloroethylene nor chromium had migrated off-site to these wells.

Changes in tropical cyclones under stabilized 1.5 and 2.0°C global warming scenarios as simulated by the Community Atmospheric Model under the HAPPI protocols

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wehner, Michael F.; Reed, Kevin A.; Loring, Burlen

The United Nations Framework Convention on Climate Change (UNFCCC) invited the scientific community to explore the impacts of a world in which anthropogenic global warming is stabilized at only 1.5°C above preindustrial average temperatures. In this paper, we present a projection of future tropical cyclone statistics for both 1.5 and 2.0°C stabilized warming scenarios with direct numerical simulation using a high-resolution global climate model. As in similar projections at higher warming levels, we find that even at these low warming levels the most intense tropical cyclones become more frequent and more intense, while simultaneously the frequency of weaker tropical stormsmore » is decreased. We also conclude that in the 1.5°C stabilization, the effect of aerosol forcing changes complicates the interpretation of greenhouse gas forcing changes.« less

Changes in tropical cyclones under stabilized 1.5 and 2.0 °C global warming scenarios as simulated by the Community Atmospheric Model under the HAPPI protocols

NASA Astrophysics Data System (ADS)

Wehner, Michael F.; Reed, Kevin A.; Loring, Burlen; Stone, Dáithí; Krishnan, Harinarayan

2018-02-01

The United Nations Framework Convention on Climate Change (UNFCCC) invited the scientific community to explore the impacts of a world in which anthropogenic global warming is stabilized at only 1.5 °C above preindustrial average temperatures. We present a projection of future tropical cyclone statistics for both 1.5 and 2.0 °C stabilized warming scenarios with direct numerical simulation using a high-resolution global climate model. As in similar projections at higher warming levels, we find that even at these low warming levels the most intense tropical cyclones become more frequent and more intense, while simultaneously the frequency of weaker tropical storms is decreased. We also conclude that in the 1.5 °C stabilization, the effect of aerosol forcing changes complicates the interpretation of greenhouse gas forcing changes.

Changes in tropical cyclones under stabilized 1.5 and 2.0°C global warming scenarios as simulated by the Community Atmospheric Model under the HAPPI protocols

DOE PAGES

Wehner, Michael F.; Reed, Kevin A.; Loring, Burlen; ...

2018-02-28

The United Nations Framework Convention on Climate Change (UNFCCC) invited the scientific community to explore the impacts of a world in which anthropogenic global warming is stabilized at only 1.5°C above preindustrial average temperatures. In this paper, we present a projection of future tropical cyclone statistics for both 1.5 and 2.0°C stabilized warming scenarios with direct numerical simulation using a high-resolution global climate model. As in similar projections at higher warming levels, we find that even at these low warming levels the most intense tropical cyclones become more frequent and more intense, while simultaneously the frequency of weaker tropical stormsmore » is decreased. We also conclude that in the 1.5°C stabilization, the effect of aerosol forcing changes complicates the interpretation of greenhouse gas forcing changes.« less

A new perspective on the regional hydrologic cycle over North and South America

NASA Astrophysics Data System (ADS)

Weng, Shu-Ping

The GEOS-1 vertically-integrated 3-hr moisture flux reanalyses and hourly-gridded United States station precipitation plus a satellite-based, 6-hr global precipitation estimate were employed to investigate the impacts of nocturnal low-level jets (LLJs) on the regional hydrological cycle over the central United States (Part I) and the subtropical plains of South America (Part II). Research stressed the influences of upper-level synoptic-scale waves (i.e., synoptic-scale forcings) upon the regional hydrologic processes, which were explored by the impacts associated with the occurrence of LLJ. Besides the conventional budget analysis, the adopted `synoptic-forcing approach' was proven illustrative in describing these impacts through the down-scaling process of LLJs. In Part 1, the major findings include: (1)the seasonal-averaged hydrological cycle over the Great Plains is strongly affected by the occurrence of GPLLJ, (2)the synoptic-scale forcing provided by the upper-level propagating jet (ULJ) streams is essential in generating the large-scale precipitation after the GPLLJ forms from the diurnal boundary layer process, (3)without the dynamic coupling between the ULJ and LLJ, the impact of LLJ on the hydrological cycle is demonstrated to be less important, and (4)the importance of synoptic-scale forcings in preconditioning the setting of wet/dry seasons in the interannual variability of rainfall anomaly is further illustrated by examining the changes of intensity as well as the occurrence frequency between the different types of LLJ. In Part II of this study, it was found that the occurrence of Andean LLJ represents a transient episode that detours the climatic rainfall activity along the South Atlantic Convergent Zone (SACZ) to the subtropical plains (Brazilian Nordeste) in its southwestern (northeastern) flank. The appearance of a seesaw pattern in the rainfall and flux convergence anomalies along the southeastern portion of South America, which is spatially in quadrature with the seasonal mean circulation, reflects the synoptic-scale forcing generated by the upper-level propagating transient-scale waves. In this regard, the function of the Andean LLJ in providing a scale-interaction mechanism that links the synoptic-scale setting with the localized rainfall event is the same as the GPLLJ. Due to the unique geographic background such as the narrow east-west landmass extension and the relative orientation between the Andean LLJ and the ULJ, however, the enhanced rainfall activity over the subtropical plains in response to the perturbed flux convergence is smaller than the case in the GPLLJ.

Emergence of airway smooth muscle mechanical behavior through dynamic reorganization of contractile units and force transmission pathways

PubMed Central

2014-01-01

Airway hyperresponsiveness (AHR) in asthma remains poorly understood despite significant research effort to elucidate relevant underlying mechanisms. In particular, a significant body of experimental work has focused on the effect of tidal fluctuations on airway smooth muscle (ASM) cells, tissues, lung slices, and whole airways to understand the bronchodilating effect of tidal breathing and deep inspirations. These studies have motivated conceptual models that involve dynamic reorganization of both cytoskeletal components as well as contractile machinery. In this article, a biophysical model of the whole ASM cell is presented that combines 1) crossbridge cycling between actin and myosin; 2) actin-myosin disconnectivity, under imposed length changes, to allow dynamic reconfiguration of “force transmission pathways”; and 3) dynamic parallel-to-serial transitions of contractile units within these pathways that occur through a length fluctuation. Results of this theoretical model suggest that behavior characteristic of experimentally observed force-length loops of maximally activated ASM strips can be explained by interactions among the three mechanisms. Crucially, both sustained disconnectivity and parallel-to-serial transitions are necessary to explain the nature of hysteresis and strain stiffening observed experimentally. The results provide strong evidence that dynamic rearrangement of contractile machinery is a likely mechanism underlying many of the phenomena observed at timescales associated with tidal breathing. This theoretical cell-level model captures many of the salient features of mechanical behavior observed experimentally and should provide a useful starting block for a bottom-up approach to understanding tissue-level mechanical behavior. PMID:24481961

A Geography of Unmarried Cohabitation in the Americas1

PubMed Central

López-Gay, Antonio; Esteve, Albert; López-Colás, Julian; Permanyer, Iñaki; Turu, Anna; Kennedy, Sheela; Laplante, Benoît; Lesthaeghe, Ron

2014-01-01

BACKGROUND In the context of increasing cohabitation and growing demand for understanding the driving forces behind the cohabitation boom, most analyses have been carried out at a national level, not accounting for regional heterogeneity within countries. OBJECTIVE This paper presents the geography of unmarried cohabitation in the Americas. We offer a large-scale, cross-national perspective together with small-area estimates of cohabitation. We decided to produce this map because: (i) geography unveils spatial heterogeneity and challenges explanatory frameworks that may work at the international level but have low explanatory power in regard to intra-national variation. (ii) we argue that historical pockets of cohabitation can still be identified by examining the current geography of cohabitation. (iii) our map is a first step toward understanding whether the recent increase in cohabitation is an intensification of pre-existing traditions or whether it has different roots that also imply a new geography. METHODS Census microdata from 39 countries and 19,000 local units have been pulled together to map the prevalence of cohabitation among women. RESULTS The results show inter- and intra-national regional contrasts. The highest rates of cohabitation are found in areas of Central America, the Caribbean, Colombia and Peru. The lowest rates are mainly found in the United States and Mexico. In all countries the spatial autocorrelation statistics indicates substantial spatial heterogeneity. CONCLUSIONS Our results raise the question as to which forces have shaped these patterns and remind us that such forces need to be taken into account to understand recent patterns, particularly increases, in cohabitation. PMID:26161036

Measurement of gravitational time dilation: An undergraduate research project

NASA Astrophysics Data System (ADS)

Burns, M. Shane; Leveille, Michael D.; Dominguez, Armand R.; Gebhard, Brian B.; Huestis, Samuel E.; Steele, Jeffrey; Patterson, Brian; Sell, Jerry F.; Serna, Mario; Gearba, M. Alina; Olesen, Robert; O'Shea, Patrick; Schiller, Jonathan

2017-10-01

General relativity predicts that clocks run more slowly near massive objects. The effect is small—a clock at sea level lags behind one 1000 m above sea level by only 9.4 ns/day. Here, we demonstrate that a measurement of this effect can be done by undergraduate students. Our paper describes an experiment conducted by undergraduate researchers at Colorado College and the United States Air Force Academy to measure gravitational time dilation. The measurement was done by comparing the signals generated by a GPS frequency standard (sea-level time) to a Cs-beam frequency standard at seven different altitudes above sea level. We found that our measurements are consistent with the predictions of general relativity.

USAF bioenvironmental noise data handbook. Volume 168: MB-3 tester, pressurized cabin leakage, aircraft

NASA Astrophysics Data System (ADS)

Rau, T. H.

1982-06-01

The MB-3 Tester is an electric motor-driven cabin leakage tester designed to furnish pressurized air to the aircraft at controlled pressures and temperatures during ground pressurization of aircraft cockpits and pressurized compartments. This report provides measured data defining the bioacoustic environments produced by this unit operating at a normal rated/load condition. Near-field data are reported for 37 locations in a wide variety of physical and psychoacoustic measures: overall and band sound pressure levels, C-weighted and A-weighted sound levels, preferred speech interference level, perceived noise level, and limiting times for total daily exposure of personnel with and without standard Air Force ear protectors.

The Correlation of Radon Concentration with Various Building Attributes at U.S. Air Force Bases

DTIC Science & Technology

1992-08-01

these daughter products that continue to decay giving off radiation which can then lead to the development of lung cancer . The United States Air Force...USAF) is concerned about the increased risk of developing lung cancer by persons exposed to elevated levels of radon in their domiciles and in their...CONOM 0 S * 0 0 a N&NO.)C Nowfum - a w em C mec0- C Mama - 00 4.4 .Q0 0 40 VO O 02ýCt > a MW 0 5 O 0 500 0 ’-ONM > Co S- -W N 00l 0 N 0 O--0 CPe go - Na Wm

Academic and Psychosocial Factors Influencing Female Cadets' Intent to Persist in Reserve Officer Training Corps (ROTC) and Commission in the United States Air Force or Army

ERIC Educational Resources Information Center

Shannon, Amy Theresa

2013-01-01

In spite of representation in enlisted ranks, women are underrepresented among top leadership positions within the military. As the largest commissioning source, ROTC plays a vital role in increasing the number of female military officers. There is substantial evidence that female cadets are retained at lower levels than male cadets during their…

Joint Force Quarterly. Issue 53, 2nd Quarter 2009

DTIC Science & Technology

2009-04-01

WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) National Defense University,260 Fifth Avenue, S.W. ( Building 64, Room 2505),Fort...improve the reader’s professional understand- ing or performance ? Speak to the implications from the operational to the strategic level of influence and...with building nuclear power plants. If this projection is accurate, significant energy dividends resulting from the nuclear agreement are unlikely

Effectiveness and Cost of Alcohol Rehabilitation in the United States Air Force.

DTIC Science & Technology

1981-12-01

PAGE BEFORE COMPLETING PORN 1. 19PRT UM14 - 2. GOVT ACCESSION NOS RECIPIENT’S CATALOG HUNGER 4. TILE (AIN S"II. TYPE OF REPORT & PERIOD COVERED in te...suggests physical addiction . Clients reported substantial improvement after treatment. Although the impairment rate following treatment remained about...symptoms that suggests physical addiction . 2. Nondependent Problems-reflecting serious alcohol-related impairment without high levels of dependence

Joint Force Quarterly. Number 11, Spring 1996

DTIC Science & Technology

1996-05-01

legally constituted roles is at an unprecedented level. While much has been accomplished, much remains to be done for hemispheric security. In particular...traditional threats and appre- hensions in the region, such as territo- rial claims, drug-trafficking, organized crime , and terrorism. The Core Issues...commerce and trade and, per- haps most significant, drive decisions to emigrate. Sixty percent of over a million legal immigrants annually to the United

Mobile Strike force 2010

DTIC Science & Technology

1994-09-23

States Army Inrtntry Center, Fort Beanning Georgia, served as the MSF 0-3. MAY Kevin Lee, Course Manager, United States Army ntelligence Center, Fort...possess mobility and protei levels sufficent for it to operate in conjunction with the FMBT. Firepower will include a lnran-mge minkge (TOW follow...Experience has shown that composite artillery battalions don’t work very well due to logistics resupply and ammo problem. £ To achieve effectivenus vith deep

Clinical practice guidelines for support of the family in the patient-centered intensive care unit: American College of Critical Care Medicine Task Force 2004-2005.

PubMed

Davidson, Judy E; Powers, Karen; Hedayat, Kamyar M; Tieszen, Mark; Kon, Alexander A; Shepard, Eric; Spuhler, Vicki; Todres, I David; Levy, Mitchell; Barr, Juliana; Ghandi, Raj; Hirsch, Gregory; Armstrong, Deborah

2007-02-01

To develop clinical practice guidelines for the support of the patient and family in the adult, pediatric, or neonatal patient-centered ICU. A multidisciplinary task force of experts in critical care practice was convened from the membership of the American College of Critical Care Medicine (ACCM) and the Society of Critical Care Medicine (SCCM) to include representation from adult, pediatric, and neonatal intensive care units. The task force members reviewed the published literature. The Cochrane library, Cinahl, and MedLine were queried for articles published between 1980 and 2003. Studies were scored according to Cochrane methodology. Where evidence did not exist or was of a low level, consensus was derived from expert opinion. The topic was divided into subheadings: decision making, family coping, staff stress related to family interactions, cultural support, spiritual/religious support, family visitation, family presence on rounds, family presence at resuscitation, family environment of care, and palliative care. Each section was led by one task force member. Each section draft was reviewed by the group and debated until consensus was achieved. The draft document was reviewed by a committee of the Board of Regents of the ACCM. After steering committee approval, the draft was approved by the SCCM Council and was again subjected to peer review by this journal. More than 300 related studies were reviewed. However, the level of evidence in most cases is at Cochrane level 4 or 5, indicating the need for further research. Forty-three recommendations are presented that include, but are not limited to, endorsement of a shared decision-making model, early and repeated care conferencing to reduce family stress and improve consistency in communication, honoring culturally appropriate requests for truth-telling and informed refusal, spiritual support, staff education and debriefing to minimize the impact of family interactions on staff health, family presence at both rounds and resuscitation, open flexible visitation, way-finding and family-friendly signage, and family support before, during, and after a death.

United States Air Force 611th Air Support Group/Civil Engineering Squadron, Elmendorf AFB, Alaska. Decision document for no further response action planned Oliktok Point Radar Installation, Alaska. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Karmi, S.

1996-06-03

This Decision Document discusses the selection of no further action as the recommended action for four sites located at the Oliktok Point radar installation. The United States Air Force (Air Force) completed a Remedial Investigation/Feasibility Study and a Risk Assessment for the eight sites located at the Oliktok Point installation (U.S. Air Force 1996a,b). Based on the findings of these activities, four sites are recommended for no further action.

Evaluating the Validity of the U.S. Military’s Global Empire

DTIC Science & Technology

2015-03-26

With this status came an unchecked and impressive global force posture . While the United States dramatically cut the number of personnel in Western...evaluates the currant pre-positioned equipment concepts, and evaluates Operation Enduring Freedom (Afghanistan) as a case study for Force Posture . The...conclusion offers five recommendations for the future of United States global force posture and actions that support access. 15. SUBJECT TERMS 16

Countering Enemy Special Purpose Forces. An Evolving Mission for United States Special Operations Forces

DTIC Science & Technology

2001-05-01

proper planning and preparation, our LOCs become lucrative high pay -off targets for our adversaries. Similar to United States doctrine, enemy SPF will...guerillas, saboteurs, terrorists, and special operations forces. This term will be used to differentiate between friendly SOF and enemy SOF. The author...Wellington’s proficient use of irregulars against the French Army during the Peninsular Campaign; and the Russian partisans that significantly

Running on Empty: The Development of Helicopter Aerial Refueling and Implications for Future USAF Combat Rescue Capabilities

DTIC Science & Technology

1997-03-01

Haiti, Somalia, Liberia, and Bosnia. The future appears very busy for Air Force rescue units as well. According to ?Strategic Assessment 1996?Instruments...13 COMTEMPORARY ROLE OF AIR REFUELING IN US AIR FORCE SEARCH AND RESCUE...places such as Haiti, Somalia, Liberia, and Bosnia. The future appears very busy for Air Force rescue units as well. According to “Strategic Assessment

75 FR 32750 - US Air Force Scientific Advisory Board Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-09

... DEPARTMENT OF DEFENSE Department of the Air Force US Air Force Scientific Advisory Board Notice of Meeting AGENCY: Department of the Air Force, US Air Force Scientific Advisory Board. ACTION: Meeting....150, the Department of Defense announces that the United States Air Force Scientific Advisory Board...

Novel Behavioral and Neural Evidences for Age-Related changes in Force complexity.

PubMed

Chen, Yi-Ching; Lin, Linda L; Hwang, Ing-Shiou

2018-02-17

This study investigated age-related changes in behavioral and neural complexity for a polyrhythmic movement, which appeared to be an exception to the loss of complexity hypothesis. Young (n = 15; age = 24.2 years) and older (15; 68.1 years) adults performed low-level force-tracking with isometric index abduction to couple a compound sinusoidal target. Multi-scale entropy (MSE) of tracking force and inter-spike interval (ISI) of motor unit (MU) in the first dorsal interosseus muscle were assessed. The MSE area of tracking force at shorter time scales of older adults was greater (more complex) than that of young adults, whereas an opposite trend (less complex for the elders) was noted at longer time scales. The MSE area of force fluctuations (the stochastic component of the tracking force) were generally smaller (less complex) for older adults. Along with greater mean and coefficient of ISI, the MSE area of the cumulative discharge rate of elders tended to be lower (less complex) than that of young adults. In conclusion, age-related complexity changes in polyrhythmic force-tracking depended on the time scale. The adaptive behavioral consequences could be multi-factorial origins of the age-related impairment in rate coding, increased discharge noises, and lower discharge complexity of pooled MUs.

Discharge properties of abductor hallucis before, during, and after an isometric fatigue task.

PubMed

Kelly, Luke A; Racinais, Sebastien; Cresswell, Andrew G

2013-08-01

Abductor hallucis is the largest muscle in the arch of the human foot and comprises few motor units relative to its physiological cross-sectional area. It has been described as a postural muscle, aiding in the stabilization of the longitudinal arch during stance and gait. The purpose of this study was to describe the discharge properties of abductor hallucis motor units during ramp and hold isometric contractions, as well as its discharge characteristics during fatigue. Intramuscular electromyographic recordings from abductor hallucis were made in 5 subjects; from those recordings, 42 single motor units were decomposed. Data were recorded during isometric ramp contractions at 60% maximum voluntary contraction (MVC), performed before and after a submaximal isometric contraction to failure (mean force 41.3 ± 15.3% MVC, mean duration 233 ± 116 s). Motor unit recruitment thresholds ranged from 10.3 to 54.2% MVC. No significant difference was observed between recruitment and derecruitment thresholds or their respective discharge rates for both the initial and postfatigue ramp contractions (all P > 0.25). Recruitment threshold was positively correlated with recruitment discharge rate (r = 0.47, P < 0.03). All motor units attained similar peak discharge rates (14.0 ± 0.25 pulses/s) and were not correlated with recruitment threshold. Thirteen motor units could be followed during the isometric fatigue task, with a decline in discharge rate and increase in discharge rate variability occurring in the final 25% of the task (both P < 0.05). We have shown that abductor hallucis motor units discharge relatively slowly and are considerably resistant to fatigue. These characteristics may be effective for generating and sustaining the substantial level of force that is required to stabilize the longitudinal arch during weight bearing.

Effects of Barbell Deadlift Training on Submaximal Motor Unit Firing Rates for the Vastus Lateralis and Rectus Femoris

PubMed Central

Stock, Matt S.; Thompson, Brennan J.

2014-01-01

Previous investigations that have studied motor unit firing rates following strength training have been limited to small muscles, isometric training, or interventions involving exercise machines. We examined the effects of ten weeks of supervised barbell deadlift training on motor unit firing rates for the vastus lateralis and rectus femoris during a 50% maximum voluntary contraction (MVC) assessment. Twenty-four previously untrained men (mean age  = 24 years) were randomly assigned to training (n = 15) or control (n = 9) groups. Before and following the intervention, the subjects performed isometric testing of the right knee extensors while bipolar surface electromyographic signals were detected from the two muscles. The signals were decomposed into their constituent motor unit action potential trains, and motor units that demonstrated accuracy levels less than 92.0% were not considered for analysis. One thousand eight hundred ninety-two and 2,013 motor units were examined for the vastus lateralis and rectus femoris, respectively. Regression analyses were used to determine the linear slope coefficients (pulses per second [pps]/% MVC) and y-intercepts (pps) of the mean firing rate and firing rate at recruitment versus recruitment threshold relationships. Deadlift training significantly improved knee extensor MVC force (Cohen's d = .70), but did not influence force steadiness. Training had no influence on the slopes and y-intercepts for the mean firing rate and firing rate at recruitment versus recruitment threshold relationships. In agreement with previous cross-sectional comparisons and randomized control trials, our findings do not support the notion that strength training affects the submaximal control of motor units. PMID:25531294

7. TOP SURFACES OF FOUR HYDRAULIC UNITS TO DRIVE COMPRESSORS. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. TOP SURFACES OF FOUR HYDRAULIC UNITS TO DRIVE COMPRESSORS. Looking southeast along rear of building. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Helium Compression Plant, Test Area 1-115, intersection of Altair & Saturn Boulevards, Boron, Kern County, CA

Innovations in Site Characterization Case Study: Hanscom Air Force Base, Operable Unit 1

EPA Pesticide Factsheets

This document is a condensation of the information provided in the much more detailed Hanscom AFB Report entitled A Dynamic Site Investigation: Adaptive Sampling and Analysis Program for Operable Unit 1 at Hanscom Air Force Base, Bedford, Massachusetts.

78 FR 20900 - Proposed Collection; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-08

...; Comment Request AGENCY: United States Air Force Logistics Transformation Office (HQ USAF/A4IT), DoD... United States Air Force Logistics Transformation Office announces a proposed public information... identify necessary course corrections to ensure all personnel have received the information and education...

Tradeoffs between chilling and forcing in satisfying dormancy requirements for Pacific Northwest tree species

PubMed Central

Harrington, Constance A.; Gould, Peter J.

2015-01-01

Many temperate and boreal tree species have a chilling requirement, that is, they need to experience cold temperatures during fall and winter to burst bud normally in the spring. Results from trials with 11 Pacific Northwest tree species are consistent with the concept that plants can accumulate both chilling and forcing units simultaneously during the dormant season and they exhibit a tradeoff between amount of forcing and chilling. That is, the parallel model of chilling and forcing was effective in predicting budburst and well chilled plants require less forcing for bud burst than plants which have received less chilling. Genotypes differed in the shape of the possibility line which describes the quantitative tradeoff between chilling and forcing units. Plants which have an obligate chilling requirement (Douglas-fir, western hemlock, western larch, pines, and true firs) and received no or very low levels of chilling did not burst bud normally even with long photoperiods. Pacific madrone and western redcedar benefited from chilling in terms of requiring less forcing to promote bud burst but many plants burst bud normally without chilling. Equations predicting budburst were developed for each species in our trials for a portion of western North America under current climatic conditions and for 2080. Mean winter temperature was predicted to increase 3.2–5.5°C and this change resulted in earlier predicted budburst for Douglas-fir throughout much of our study area (up to 74 days earlier) but later budburst in some southern portions of its current range (up to 48 days later) as insufficient chilling is predicted to occur. Other species all had earlier predicted dates of budburst by 2080 than currently. Recent warming trends have resulted in earlier budburst for some woody plant species; however, the substantial winter warming predicted by some climate models will reduce future chilling in some locations such that budburst will not consistently occur earlier. PMID:25784922

Responses of stream nitrate and DOC loadings to hydrological forcing and climate change in an upland forest of the northeastern United States

Treesearch

Stephen D. Sebestyen; Elizabeth W. Boyer; James B. Shanley

2009-01-01

In coming decades, higher annual temperatures, increased growing season length, and increased dormant season precipitation are expected across the northeastern United States in response to anthropogenic forcing of global climate. We synthesized long-term stream hydrochemical data from the Sleepers River Research Watershed in Vermont, United States, to explore the...

UNITED STATES SPECIAL OPERATIONS FORCES IN AFRICA

DTIC Science & Technology

2016-02-16

AIR WAR COLLEGE AIR UNIVERSITY UNITED STATES SPECIAL OPERATIONS FORCES IN AFRICA by Keith I. Crawford, Lt Col, USAF A Research Report... Africa Command in 2007 manifested recognition that the United States has increasing strategic national interests on the continent of Africa that are...importance of airborne ISR and basing access. Introduction In February of 2007, President George W. Bush announced the creation of Africa

Accuracy assessment of a surface electromyogram decomposition system in human first dorsal interosseus muscle

NASA Astrophysics Data System (ADS)

Hu, Xiaogang; Rymer, William Z.; Suresh, Nina L.

2014-04-01

Objective. The aim of this study is to assess the accuracy of a surface electromyogram (sEMG) motor unit (MU) decomposition algorithm during low levels of muscle contraction. Approach. A two-source method was used to verify the accuracy of the sEMG decomposition system, by utilizing simultaneous intramuscular and surface EMG recordings from the human first dorsal interosseous muscle recorded during isometric trapezoidal force contractions. Spike trains from each recording type were decomposed independently utilizing two different algorithms, EMGlab and dEMG decomposition algorithms. The degree of agreement of the decomposed spike timings was assessed for three different segments of the EMG signals, corresponding to specified regions in the force task. A regression analysis was performed to examine whether certain properties of the sEMG and force signal can predict the decomposition accuracy. Main results. The average accuracy of successful decomposition among the 119 MUs that were common to both intramuscular and surface records was approximately 95%, and the accuracy was comparable between the different segments of the sEMG signals (i.e., force ramp-up versus steady state force versus combined). The regression function between the accuracy and properties of sEMG and force signals revealed that the signal-to-noise ratio of the action potential and stability in the action potential records were significant predictors of the surface decomposition accuracy. Significance. The outcomes of our study confirm the accuracy of the sEMG decomposition algorithm during low muscle contraction levels and provide confidence in the overall validity of the surface dEMG decomposition algorithm.

Association of work-related stress with mental health problems in a special police force unit.

PubMed

Garbarino, Sergio; Cuomo, Giovanni; Chiorri, Carlo; Magnavita, Nicola

2013-01-01

Law and order enforcement tasks may expose special force police officers to significant psychosocial risk factors. The aim of this work is to investigate the relationship between job stress and the presence of mental health symptoms while controlling sociodemographical, occupational and personality variables in special force police officers. At different time points, 292 of 294 members of the 'VI Reparto Mobile', a special police force engaged exclusively in the enforcement of law and order, responded to our invitation to complete questionnaires for the assessment of personality traits, work-related stress (using the Demand-Control-Support (DCS) and the Effort-Reward-Imbalance (ERI) models) and mental health problems such as depression, anxiety and burnout. Regression analyses showed that lower levels of support and reward and higher levels of effort and overcommitment were associated with higher levels of mental health symptoms. Psychological screening revealed 21 (7.3%) likely cases of mild depression (Beck Depression Inventory, BDI≥10). Officers who had experienced a discrepancy between work effort and rewards showed a marked increase in the risk of depression (OR 7.89, 95% CI 2.32 to 26.82) when compared with their counterparts who did not perceive themselves to be in a condition of distress. The findings of this study suggest that work-related stress may play a role in the development of mental health problems in police officers. The prevalence of mental health symptoms in the cohort investigated here was low, but not negligible in the case of depression. Since special forces police officers have to perform sensitive tasks for which a healthy psychological functioning is needed, the results of this study suggest that steps should be taken to prevent distress and improve the mental well-being of these workers.

A prospective study of carpal tunnel syndrome: workplace and individual risk factors

PubMed Central

Burt, Susan; Deddens, James A; Crombie, Ken; Jin, Yan; Wurzelbacher, Steve; Ramsey, Jessica

2015-01-01

Objectives To quantify the risk for carpal tunnel syndrome (CTS) from workplace physical factors, particularly hand activity level and forceful exertion, while taking into account individual factors including age, gender, body mass index (BMI), and pre-existing medical conditions. Methods Three healthcare and manufacturing workplaces were selected for inclusion on the basis of range of exposure to hand activity level and forceful exertion represented by their jobs. Each study participants job tasks were observed and evaluated ’ onsite and videotaped for further analysis, including frequency and duration of exertion and postural deviation. Individual health assessment entailed electrodiagnostic testing of median and ulnar nerves, physical examination and questionnaires at baseline with annual follow-up for 2 years. Results The incidence of dominant hand CTS during the study was 5.11 per 100 person-years (29 cases). Adjusted HRs for dominant hand CTS were as follows: working with forceful exertion ≥20% but <60% of the time: 2.83 (1.18, 6.79) and ≥60% of the time vs <20%: 19.57 (5.96, 64.24), BMI ≥30 kg/m2 (obesity): 3.19 (1.28, 7.98). The American Conference for Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV) for hand activity level also predicted CTS, HR=1.40 (1.11, 1.78) for each unit increase in the TLV ratio, controlling for obesity and job strain. Conclusions Workplace and individual risk factors both contribute to the risk for CTS. Time spent in forceful exertion can be a greater risk for CTS than obesity if the job exposure is high. Preventive workplace efforts should target forceful exertions. PMID:23788614

A programmable and portable NMES device for drop foot correction and blood flow assist applications.

PubMed

Breen, Paul P; Corley, Gavin J; O'Keeffe, Derek T; Conway, Richard; Olaighin, Gearóid

2009-04-01

The Duo-STIM, a new, programmable and portable neuromuscular stimulation system for drop foot correction and blood flow assist applications is presented. The system consists of a programmer unit and a portable, programmable stimulator unit. The portable stimulator features fully programmable, sensor-controlled, constant-voltage, dual-channel stimulation and accommodates a range of customized stimulation profiles. Trapezoidal and free-form adaptive stimulation intensity envelope algorithms are provided for drop foot correction applications, while time dependent and activity dependent algorithms are provided for blood flow assist applications. A variety of sensor types can be used with the portable unit, including force sensitive resistor-based foot switches and MEMS-based accelerometer and gyroscope devices. The paper provides a detailed description of the hardware and block-level system design for both units. The programming and operating procedures for the system are also presented. Finally, functional bench test results for the system are presented.

A programmable and portable NMES device for drop foot correction and blood flow assist applications.

PubMed

Breen, Paul P; Corley, Gavin J; O'Keeffe, Derek T; Conway, Richard; OLaighin, Gearoid

2007-01-01

The Duo-STIM, a new, programmable and portable neuromuscular stimulation system for drop foot correction and blood flow assist applications is presented. The system consists of a programmer unit and a portable, programmable stimulator unit. The portable stimulator features fully programmable, sensor-controlled, constant-voltage, dual-channel stimulation and accommodates a range of customized stimulation profiles. Trapezoidal and free-form adaptive stimulation intensity envelope algorithms are provided for drop foot correction applications, while time dependent and activity dependent algorithms are provided for blood flow assist applications. A variety of sensor types can be used with the portable unit, including force sensitive resistor based foot switches and NMES based accelerometer and gyroscope devices. The paper provides a detailed description of the hardware and block-level system design for both units. The programming and operating procedures for the system are also presented. Finally, functional bench test results for the system are presented.

Rapid Parallel Calculation of shell Element Based On GPU

NASA Astrophysics Data System (ADS)

Wanga, Jian Hua; Lia, Guang Yao; Lib, Sheng; Li, Guang Yao

2010-06-01

Long computing time bottlenecked the application of finite element. In this paper, an effective method to speed up the FEM calculation by using the existing modern graphic processing unit and programmable colored rendering tool was put forward, which devised the representation of unit information in accordance with the features of GPU, converted all the unit calculation into film rendering process, solved the simulation work of all the unit calculation of the internal force, and overcame the shortcomings of lowly parallel level appeared ever before when it run in a single computer. Studies shown that this method could improve efficiency and shorten calculating hours greatly. The results of emulation calculation about the elasticity problem of large number cells in the sheet metal proved that using the GPU parallel simulation calculation was faster than using the CPU's. It is useful and efficient to solve the project problems in this way.

Research concerning the evaluation of the connection forces in the joints of the sucker rod pumping units mechanism

NASA Astrophysics Data System (ADS)

Bădoiu, D.; Petrescu, M. G.; Antonescu, N. N.; Toma, G.

2018-01-01

At present, the sucker rod pumping installations are the most used in the case of the wells in production, when an eruptive exploitation is not possible. The practice has demonstrated that an important role in increasing safety in the operation of the pumping units has the design of the various component bearings because of the extremely high values of the connection forces to which they are loaded. That is why it is necessary to establish as accurately as possible the values of these connecting forces. In the paper is analyzed the dynamics of a conventional pumping unit mechanism. The dynamic study which allows establishing the values of the connecting forces in the joints is performed within the Assur structural groups. The dynamic analysis was implemented into a computer program using Maple programming environment and finally it has been presented some simulation results in the case of a C-320D-256-100 pumping unit.

Total Force Fitness in units part 1: military demand-resource model.

PubMed

Bates, Mark J; Fallesen, Jon J; Huey, Wesley S; Packard, Gary A; Ryan, Diane M; Burke, C Shawn; Smith, David G; Watola, Daniel J; Pinder, Evette D; Yosick, Todd M; Estrada, Armando X; Crepeau, Loring; Bowles, Stephen V

2013-11-01

The military unit is a critical center of gravity in the military's efforts to enhance resilience and the health of the force. The purpose of this article is to augment the military's Total Force Fitness (TFF) guidance with a framework of TFF in units. The framework is based on a Military Demand-Resource model that highlights the dynamic interactions across demands, resources, and outcomes. A joint team of subject-matter experts identified key variables representing unit fitness demands, resources, and outcomes. The resulting framework informs and supports leaders, support agencies, and enterprise efforts to strengthen TFF in units by (1) identifying TFF unit variables aligned with current evidence and operational practices, (2) standardizing communication about TFF in units across the Department of Defense enterprise in a variety of military organizational contexts, (3) improving current resources including evidence-based actions for leaders, (4) identifying and addressing of gaps, and (5) directing future research for enhancing TFF in units. These goals are intended to inform and enhance Service efforts to develop Service-specific TFF models, as well as provide the conceptual foundation for a follow-on article about TFF metrics for units. Reprint & Copyright © 2013 Association of Military Surgeons of the U.S.

[Medical support of the Armed Forces of the Russian Federation: the results of the activities and the main tasks for 2015].

PubMed

Fisun, A Ia

2015-01-01

Presented the directions of activity of the medical service in the past year, including improving the legal framework, the optimization of medical management software, improving combat and mobilization readiness of units of the army, the optimization of therapeutic and preventive activities, implementation of innovative technologies, increasing mobility of units and subunits, their level of equipping with modern samples of property, training of qualified personnel, intensify research and etc. Analyzed and formulated directions of development of military medicine in 2015, including improvement of combat and mobilization readiness of the management body, military and medical organizations and departments, improving the legal framework of the military health care, holding among the troops interventions for the prevention morbidity of personnel by pneumonia and meningitis, work with commanders at all levels to ensure the preservation and strengthening of health of servicemen, improving of the system of early and active detection of diseases in the military, providing a guaranteed level of care to all contingent Ministry of Defense, improving the quality and accessibility of sanatorium treatment, maintaining constant readiness of medical special forces to carry out tasks for the purpose, improvement of professional training of personnel of the medical service, providing qualitative preparation of government medical service to participate in the training of troops, implementation of unexpected problems, equipping of army medical service with modern medical equipment finishing of the construction and renovation of military medical organizations facilities, improvement of social protection of personnel and many others.

Installation Restoration Program Stage 3. Remedial Investigation/ Feasibility Study Elmendorf AFB, Alaska. Volume 2. Section 5 - Bibliography Text

DTIC Science & Technology

1990-05-01

ELME’IDORF AFB, AK UNITED STATES AIR FORCE OCCUPATIONAL & ENVIRONMENTAL HEALTH LABORATORY (AFSC) ilb(. IiCAL Sr.(VICES DIVISION (AFOEHLi £3) I BROOKS AIR...UNITED STATES AIR FORCE OCCUPATIONAL AND ENVIRONMENTAL HEALTH LABORATORY (AFSC) TECHNICAL SERVICES DIVISION (AFOEHL/TS) BROOKS AIR FORCE BASE, TEXAS...the following criteria: technical feasibility, institutional requirements, environmental impacts, public health impacts, and cost. This Alternative

Coalition Logistics - The Multinational Force and Observers Model

DTIC Science & Technology

1986-05-19

MISSION The mission of the MFO, as specified by the protocol , is to supervise implemeutation of the peace treaty and to employ its best efforts to prevent ...result, a protocol was -- negotiated, calling for a multinational military force and civilian- ---- observer unit to serve in the Sinai--outside the...auspices of the United Nations.2 In this way, the protocol of 3 August 1981 created the Multinational Force and Observers and directed Lhat it be

Employee Involvement White Collar Work Force (Phase 1)

DTIC Science & Technology

1991-07-01

TITLE AND SUBTITLE Employee Involvement White Collar Work Force (Phase 1) 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S...N COMMITTEE August 1991 NSRP 0337 AL EFFECTS TRANSFER Employee Involvement White Collar Work Force (Phase 1) UNITED STATES NAVY David Taylor Research...report. AS used In the above, “Persons acting on behalf of the United States Navy” includes any employee , contractor, or subcontractor to the

The United States Space Force: Not If, But When

DTIC Science & Technology

2016-06-01

context behind the genesis of the United States Air Force in an attempt to understand what contextual factors must be present in order for the nation to...the contextual elements that surrounded the creation of the Air Force, the paper is able to extrapolate what the necessary and sufficient conditions...military. The rise of the USAF from the US Army Air Corps not only resulted from technological developments, but also from many contextual

United States Air Force Summer Research Program -- 1993. Volume 3. Phillips Laboratory

DTIC Science & Technology

1993-12-01

PHILLIPS LABORATORY KIRTLAND AIR FORCE BASE, NEW MEXICO SPONSORED BY: AIR FORCE OFFICE OF SCIENTIFIC RESEARCH ROLLING AIR FORCE BASE, WASHINGTON ,D.C...Report for. Summer Faculty Research Program at Phillips Laboratory Kirtland Air Force Base Sponsored by: Air Force Offlce of Scientific Research ...Prcgram Phillips Laboratory Kirtland

78 FR 49484 - Exchange of Air Force Real Property for Non-Air Force Real Property

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-14

... DEPARTMENT OF DEFENSE Department of Air Force Exchange of Air Force Real Property for Non-Air Force Real Property SUMMARY: Notice identifies excess Federal real property under administrative jurisdiction of the United States Air Force it intends to exchange for real property not currently owned by the...

76 FR 28215 - U.S. Air Force Scientific Advisory Board Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-16

... DEPARTMENT OF DEFENSE Department of the Air Force U.S. Air Force Scientific Advisory Board Notice of Meeting AGENCY: Department of the Air Force, U.S. Air Force Scientific Advisory Board, DoD. ACTION... 102-3.150, the Department of Defense announces that the United States Air Force Scientific Advisory...

76 FR 18537 - U.S. Air Force Scientific Advisory Board; Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-04

... DEPARTMENT OF DEFENSE Department of the Air Force U.S. Air Force Scientific Advisory Board; Notice of Meeting AGENCY: Department of the Air Force, US Air Force Scientific Advisory Board. ACTION... 102-3.150, the Department of Defense announces that the United States Air Force Scientific Advisory...

Muscle length-dependent contribution of motoneuron Cav1.3 channels to force production in model slow motor unit.

PubMed

Kim, Hojeong

2017-07-01

Persistent inward current (PIC)-generating Ca v 1.3 channels in spinal motoneuron dendrites are thought to be actively recruited during normal behaviors. However, whether and how the activation of PIC channels influences force output of motor unit remains elusive. Here, building a physiologically realistic model of slow motor unit I demonstrated that force production induced by the PIC activation is much smaller for short than lengthened muscles during the regular firing of the motoneuron that transitions from the quiescent state by either a brief current pulse at the soma or a brief synaptic excitation at the dendrites. By contrast, the PIC-induced force potentiation was maximal for short muscles when the motoneuron switched from a stable low-frequency firing state to a stable high-frequency firing state by the current pulse at the soma. Under the synaptic excitation at the dendrites, however, the force could not be potentiated by the transitioning of the motoneuron from a low- to a high-frequency firing state due to the simultaneous onset of PIC at the dendrites and firing at the soma. The strong dependency of the input-output relationship of the motor unit on the neuromodulation and Ia afferent inputs for the PIC channels was further shown under static variations in muscle length. Taken together, these findings suggest that the PIC activation in the motoneuron dendrites may differentially affect the force production of the motor unit, depending not only on the firing state history of the motoneuron and the variation in muscle length but also on the mode of motor activity. NEW & NOTEWORTHY Ca v 1.3 channels in motoneuron dendrites are actively involved during normal motor activities. To investigate the effects of the activation of motoneuron Ca v 1.3 channels on force production, a model motor unit was built based on best-available data. The simulation results suggest that force potentiation induced by Ca v 1.3 channel activation is strongly modulated not only by firing history of the motoneuron but also by length variation of the muscle as well as neuromodulation inputs from the brainstem. Copyright © 2017 the American Physiological Society.

A nerve stimulation method to selectively recruit smaller motor-units in rat skeletal muscle.

PubMed

van Bolhuis, A I; Holsheimer, J; Savelberg, H H

2001-05-30

Electrical stimulation of peripheral nerve results in a motor-unit recruitment order opposite to that attained by natural neural control, i.e. from large, fast-fatiguing to progressively smaller, fatigue-resistant motor-units. Yet animal studies involving physiological exercise protocols of low intensity and long duration require minimal fatigue. The present study sought to apply a nerve stimulation method to selectively recruit smaller motor-units in rat skeletal muscle. Two pulse generators were used, independently supplying short supramaximal cathodal stimulating pulses (0.5 ms) and long subthreshold cathodal inactivating pulses (1.5 s) to the sciatic nerve. Propagation of action potentials was selectively blocked in nerve fibres of different diameter by adjusting the strength of the inactivating current. A tensile-testing machine was used to gauge isometric muscle force of the plantaris and both heads of the gastrocnemius muscle. The order of motor-unit recruitment was estimated from twitch characteristics, i.e. peak force and relaxation time. The results showed prolonged relaxation at lower twitch peak forces as the intensity of the inactivating current increased, indicating a reduction of the number of large motor-units to force production. It is shown that the nerve stimulation method described is effective in mimicking physiological muscle control.

The Subject Headings of the Morris Swett Library, USAFAS. Revised.

DTIC Science & Technology

1980-05-15

Royal Armoured Corps. x Armored force. Armored troops. Armored units. Mechanized force. Mechanized units. Mechanized warfare. Tank companies. Tank...g., U. S. Ary- Physical training. CAMERA MOUNTS. CAMERAS, AERIAL. II I • • ! I CAMOUFLAGE. (U 166.3h) x Air arm - amouflage. - Bibliography. - Drape

50 CFR 300.117 - Prohibitions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... provisions of the Convention or in violation of a conservation measure in force with respect to the United... have known, was harvested in violation of a conservation measure in force with respect to the United... subpart. (s) Import Dissostichus spp. with a Specially Validated DCD. (t) Import shipments of frozen...

General aviation accidents : the United States Air Force Aero Club solution

DOT National Transportation Integrated Search

1998-08-01

Aviation if an intrisically safe mode of travel. In 1994, the United States Air Force system of Aero Clubs put forth substantial effort to put a program in place (Fly Smart) to improve flying safety in it aircraft. This study compares the accident ra...

Changes in the electromechanical delay components during a fatiguing stimulation in human skeletal muscle: an EMG, MMG and force combined approach.

PubMed

Cè, Emiliano; Rampichini, Susanna; Monti, Elena; Venturelli, Massimo; Limonta, Eloisa; Esposito, Fabio

2017-01-01

Peripheral fatigue involves electrochemical and mechanical mechanisms. An electromyographic, mechanomyographic and force combined approach may permit a kinetic evaluation of the changes at the synaptic, skeletal muscle fiber, and muscle-tendon unit level during a fatiguing stimulation. Surface electromyogram, mechanomyogram, force and stimulation current were detected from the gastrocnemius medialis muscle in twenty male participants during a fatiguing stimulation (twelve blocks of 35 Hz stimulations, duty cycle 9 s on/1 s off, duration 120 s). The total electromechanical delay and its three components (between stimulation current and electromyogram, synaptic component; between electromyogram and mechanomyogram signal onset, muscle fiber electrochemical component, and between mechanomyogram and force signal onset, mechanical component) were calculated. Interday reliability and sensitivity were determined. After fatigue, peak force decreased by 48% (P < 0.05) and the total electromechanical delay and its synaptic, electrochemical and mechanical components lengthened from 25.8 ± 0.9, 1.47 ± 0.04, 11.2 ± 0.6, and 13.1 ± 1.3 ms to 29.0 ± 1.6, 1.56 ± 0.05, 12.4 ± 0.9, and 17.2 ± 0.6 ms, respectively (P < 0.05). During fatigue, the total electromechanical delay and the mechanical component increased significantly after the 40th second, and then remained stable. The synaptic and electrochemical components lengthened significantly after the 20th and 30th second, respectively. Interday reliability was high to very high, with an adequate level of sensitivity. The kinetic evaluation of the delays during the fatiguing stimulation highlighted different onsets and kinetics, with the events at synaptic level being the first to reveal a significant elongation, followed by those at the intra-fiber level. The mechanical events, which were the most affected by fatigue, were the last to lengthen.

Operationally Responsive Space Launch for Space Situational Awareness Missions

NASA Astrophysics Data System (ADS)

Freeman, T.

The United States Space Situational Awareness capability continues to be a key element in obtaining and maintaining the high ground in space. Space Situational Awareness satellites are critical enablers for integrated air, ground and sea operations, and play an essential role in fighting and winning conflicts. The United States leads the world space community in spacecraft payload systems from the component level into spacecraft and in the development of constellations of spacecraft. This position is founded upon continued government investment in research and development in space technology, which is clearly reflected in the Space Situational Awareness capabilities and the longevity of these missions. In the area of launch systems that support Space Situational Awareness, despite the recent development of small launch vehicles, the United States launch capability is dominated by unresponsive and relatively expensive launchers in the Expandable, Expendable Launch Vehicles (EELV). The EELV systems require an average of six to eight months from positioning on the launch table until liftoff. Access to space requires maintaining a robust space transportation capability, founded on a rigorous industrial and technology base. To assure access to space, the United States directed Air Force Space Command to develop the capability for operationally responsive access to space and use of space to support national security, including the ability to provide critical space capabilities in the event of a failure of launch or on-orbit capabilities. Under the Air Force Policy Directive, the Air Force will establish, organize, employ, and sustain space forces necessary to execute the mission and functions assigned including rapid response to the National Command Authorities and the conduct of military operations across the spectrum of conflict. Air Force Space Command executes the majority of spacelift operations for DoD satellites and other government and commercial agencies. The Command researched and identified a course of action that has maximized operationally responsive space for Low-Earth-Orbit Space Situational Awareness assets. On 1 Aug 06, Air Force Space Command activated the Space Development and Test Wing (SDTW) to perform development, test and evaluation of Air Force space systems and to execute advanced space deployment and demonstration projects to exploit new concepts and technologies, and rapidly migrate capabilities to the warfighter. The SDTW charged the Launch Test Squadron (LTS) to develop the operationally responsive spacelift capability for Low-Earth-Orbit Space Situational Awareness assets. The LTS created and executed a space enterprise strategy to place small payloads (1500 pounds), at low cost (less than 28M to 30M per launch), repeatable and rapidly into 100 - 255 nautical miles orbits. In doing so, the squadron provides scalable launch support services including program management support, engineering support, payload integration, and post-test evaluation for space systems. The Air Force, through the SDTW/LTS, will continue to evolve as the spacelift execution arm for Space Situational Awareness by creating small, less-expensive, repeatable and operationally responsive space launch capability.

Three-dimensional Crack Depth Profile Assessment using Near-Field Surface Acoustic Wave Signal Response (Postprint)

DTIC Science & Technology

2012-02-01

release; distribution unlimited. See additional restrictions described on inside pages STINFO COPY AIR FORCE RESEARCH...LABORATORY MATERIALS AND MANUFACTURING DIRECTORATE WRIGHT-PATTERSON AIR FORCE BASE, OH 45433-7750 AIR FORCE MATERIEL COMMAND UNITED STATES AIR FORCE...AFRL/RXLP) Materials and Manufacturing Directorate, Air Force Research Laboratory Wright-Patterson Air Force Base, OH 45433-7750 Air Force

The driving forces of land change in the Northern Piedmont of the United States

USGS Publications Warehouse

Auch, Roger F.; Napton, Darrell E.; Kambly, Steven; Moreland, Thomas R.; Sayler, Kristi L.

2012-01-01

Driving forces facilitate or inhibit land-use/land-cover change. Human driving forces include political, economic, cultural, and social attributes that often change across time and space. Remotely sensed imagery provides regional land-change data for the Northern Piedmont, an ecoregion of the United States that continued to urbanize after 1970 through conversion of agricultural and forest land covers to developed uses. Eight major driving forces facilitated most of the land conversion; other drivers inhibited or slowed change. A synergistic web of drivers may be more important in understanding land change than individual drivers by themselves.

United States Air Force 611th Air Support Group/Civil Engineering Squadron Elmendorf AFB, Alaska. Decision document for no further response action planned: Barter Island Radar Installation, Alaska. Final report, December 1995-May 1996

DOE Office of Scientific and Technical Information (OSTI.GOV)

Karmi, S.; Madden, J.; Borsetti, R.

1996-05-03

This Decision Document discusses the selection of no further action as the recommended action for nine sites located at the Barter Island radar installation. The United States Air Force (Air Force) completed a Remedial Investigation/Feasibility Study and a Risk Assessment for the 14 sites located at the Barter Island installation (U.S. Air Force 1996a,b). Based on the findings of these activities, nine sites are recommended for no further action.

Vastus lateralis surface and single motor unit EMG following submaximal shortening and lengthening contractions.

PubMed

Altenburg, Teatske M; de Ruiter, Cornelis J; Verdijk, Peter W L; van Mechelen, Willem; de Haan, Arnold

2008-12-01

A single shortening contraction reduces the force capacity of muscle fibers, whereas force capacity is enhanced following lengthening. However, how motor unit recruitment and discharge rate (muscle activation) are adapted to such changes in force capacity during submaximal contractions remains unknown. Additionally, there is limited evidence for force enhancement in larger muscles. We therefore investigated lengthening- and shortening-induced changes in activation of the knee extensors. We hypothesized that when the same submaximal torque had to be generated following shortening, muscle activation had to be increased, whereas a lower activation would suffice to produce the same torque following lengthening. Muscle activation following shortening and lengthening (20 degrees at 10 degrees /s) was determined using rectified surface electromyography (rsEMG) in a 1st session (at 10% and 50% maximal voluntary contraction (MVC)) and additionally with EMG of 42 vastus lateralis motor units recorded in a 2nd session (at 4%-47%MVC). rsEMG and motor unit discharge rates following shortening and lengthening were normalized to isometric reference contractions. As expected, normalized rsEMG (1.15 +/- 0.19) and discharge rate (1.11 +/- 0.09) were higher following shortening (p < 0.05). Following lengthening, normalized rsEMG (0.91 +/- 0.10) was, as expected, lower than 1.0 (p < 0.05), but normalized discharge rate (0.99 +/- 0.08) was not (p > 0.05). Thus, muscle activation was increased to compensate for a reduced force capacity following shortening by increasing the discharge rate of the active motor units (rate coding). In contrast, following lengthening, rsEMG decreased while the discharge rates of active motor units remained similar, suggesting that derecruitment of units might have occurred.

Stabilization and Reconstruction Operations Doctrine and Theory

DTIC Science & Technology

2014-05-22

best definition of security for our purposes, which is the reduction of civil violence to a level manageable by HN law enforcement authorities or...manner. The literature suggests determining the correct size and scope of the S&R force. Two concepts outlined in assessing correct size and scope...tolerant of political dissent. Should this be the case and the insurgency manages to create a party with a united front, then the insurgency is

United States Air Force Research Initiation Program. 1984 Research Reports. Volume 2.

DTIC Science & Technology

1986-05-01

105th Winter Annual Meeting, Symposium on Experimental Measurements and Techniques In 11. Chiu, H.H., Dynamics of Vortex Shedding and Quasi -large...conservation of quantities such as mass, momentum and energy over any group of control volumes and therefore, over the whole computational domain. The...phenomena. Peliaole and accirate experimental data ’or flowfielcs with high levels of turnulence are neginnirg to appear in literatuream. The advances in non

3,700 USAF Junior Acquisition Officers! Rebalance USAF Manning Priorities Now

DTIC Science & Technology

2017-04-06

duties because they represent basically “no-cost” manpower to the headquarters and base -level leaders. The USAF pays for their military salary and...Colonel, United States Air Force A Research Report Submitted to the Faculty In Partial Fulfillment of the Graduation Requirements Advisor: Colonel...academic research paper are those of the author and do not reflect the official policy or position of the US government, the Department of Defense

Bureau of Labor Statistics Employment Projections: Detailed Analysis of Selected Occupations and Industries. Report to the Honorable Berkley Bedell, United States House of Representatives.

ERIC Educational Resources Information Center

General Accounting Office, Washington, DC.

To compile its projections of future employment levels, the Bureau of Labor Statistics (BLS) combines the following five interlinked models in a six-step process: a labor force model, an econometric model of the U.S. economy, an industry activity model, an industry labor demand model, and an occupational labor demand model. The BLS was asked to…

1979 Reserve Force Studies Surveys: Survey Design, Sample Design and Administrative Procedures,

DTIC Science & Technology

1981-08-01

three factors: the need for a statistically significant number of usable questionnaires from different groups within the random sampls and from...Because of the multipurpose nature of these surveys and the large number of questions needed to fully address some of the topics covered, we...varies. Collection of data at the unit level is needed to accurately estimate actual reserve compensation and benefits and their possible role in both

United States Air Force Summer Faculty Research Program. 1980 Program Management Report.

DTIC Science & Technology

1980-10-01

conducted by SCEEE. The program provides opportunities for research In the physical sciences, engineering, life sciences, business, and administrative...How could it be improved? 5. Did you have any difficulty In any domestic aspects (i.e., locating suitable housing, acceptance in community, social life ...provided, trouble with family housing, not much social life . b. Stipend level? Meager - 18 Adequate- 62 Generous - b 7. Preprogram visit? Not worth expense

A Case Study of the Degree of Collaboration Between Various Levels in the Reparable Chain in the United States Air Force

DTIC Science & Technology

2005-03-01

qualitative research methods , a case study approach was selected to conduct this research . “A case study can be defined as an empirical study ... qualitative in nature, and also described the qualitative research method chosen as a case study . From 49 there, data collection was focused upon... qualitative nature of the research , a qualitative design was used to conduct the

Putting intimate partner violence on your radar.

PubMed

Collett, DeShana; Bennett, Tamara

2015-10-01

Intimate partner violence is a preventable health problem that affects more than 12 million people in the United States each year. Those affected can be of any sex, race, ethnicity, socioeconomic status, religion, education level, or sexual orientation. All clinicians should screen for intimate partner violence as part of the routine history and physical examination. This article describes the dynamics of intimate partner violence and the 2013 screening guidelines from the US Preventive Services Task Force.

32 CFR 855.22 - Air Force procedures.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 32 National Defense 6 2013-07-01 2013-07-01 false Air Force procedures. 855.22 Section 855.22 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE AIRCRAFT CIVIL AIRCRAFT USE OF UNITED STATES AIR FORCE AIRFIELDS Agreements for Civil Aircraft Use of Air Force Airfields § 855...

32 CFR 855.22 - Air Force procedures.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 6 2010-07-01 2010-07-01 false Air Force procedures. 855.22 Section 855.22 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE AIRCRAFT CIVIL AIRCRAFT USE OF UNITED STATES AIR FORCE AIRFIELDS Agreements for Civil Aircraft Use of Air Force Airfields § 855...

32 CFR 855.22 - Air Force procedures.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 6 2011-07-01 2011-07-01 false Air Force procedures. 855.22 Section 855.22 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE AIRCRAFT CIVIL AIRCRAFT USE OF UNITED STATES AIR FORCE AIRFIELDS Agreements for Civil Aircraft Use of Air Force Airfields § 855...

SI Units to be Used in Place of Imperial Units and Old Metric Units

ERIC Educational Resources Information Center

Australian Science Teachers Journal, 1975

1975-01-01

A table lists the following quantities in imperial units, old metric units, and SI units: mass, force, energy, torque, power, pressure, temperature, thermal conductivity, frequency, dynamic viscosity, and kinematic viscosity. (MLH)

Development and human resources in the Islamic world: a study of selected countries.

PubMed

Duza, M B

1987-01-01

"The present paper attempts to provide an analytical profile of development and human resources in [12] selected [Islamic] countries." The countries--Bangladesh, Somalia, Pakistan, Indonesia, Egypt, Turkey, Malaysia, Algeria, Iraq, Saudi Arabia, Kuwait, and United Arab Emirates--vary in income levels from low to high and in population size from 1 million to 159 million. Using data from the World Bank and the Population Council, comparisons are made on the basis of mortality and fertility levels, family size, income, urbanization, labor force size and growth, education, nutrition, and health. Governmental policy changes and future directions are discussed. excerpt

Aircraft: United States Air Force Child Care Program Activity Guide.

ERIC Educational Resources Information Center

Boggs, Juanita; Brant, Linda

General information about United States' aircraft is provided in this program activity guide for teachers and caregivers in Air Force preschools and day care centers. The guide includes basic information for teachers and caregivers, basic understandings, suggested teaching methods and group activities, vocabulary, ideas for interest centers, and…

Principles of Technology Curriculum Guide. Curriculum Development. Bulletin 1812.

ERIC Educational Resources Information Center

Louisiana State Dept. of Education, Baton Rouge. Div. of Vocational Education.

This document describes minimum competencies and suggested student activities for a seven-unit course called Principles of Technology. The instructional units are called Force, Work, Rate, Resistance, Energy, Power, and Force Transformers. The first section of the document contains information on how to use the guide, goals for industrial…

Commitment to Liberal Education at the United States Air Force Academy

ERIC Educational Resources Information Center

Enger, Rolf C.; Jones, Steven K.; Born, Dana H.

2010-01-01

Located just north of Colorado Springs, Colorado, the United States Air Force Academy (USAFA) is one of the nation's federally funded military service academies. With an enrollment of approximately 4,400 undergraduates, the academy offers an integrated four-year curriculum of academics, athletics, leadership and character development, military…

77 FR 8838 - Proposed Collection; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-15

.... Title; Associated Form; and OMB Number: Nomination For Appointment To The United States Military Academy... form to nominate constituents to the three DoD Academies, West Point, Annapolis and Air Force. Data... outlined in AFI 36-2019, Appointment to the United States Air Force Academy. Affected Public: Applicants to...

United States Air Force Response to Problems of Child Abuse within the Military Community.

DTIC Science & Technology

1985-01-01

The Child Abuse Prevention and Treatment Act became national law in the United States. This act authorized a National Center on Child Abuse and...Neglect to compile information, operate a clearinghouse on programs showing promise of success in prevention, identification and treatment of child abuse , publish...Force base to investigate and evaluate suspected child abuse cases. This study focuses on child abuse in the Air Force community rather than in the

JPRS Report, East Asia, Southeast Asia, The Decisive Years: Memoirs of Vietnamese Senior General Hoang Van Thai

DTIC Science & Technology

1987-06-23

governmental system , in order to maintain and develop the forces of the revolution in the governmental administration and the mass organizations, build... operatinal modes in order to, in future years, form three strong fists (the rural areas, the urban areas, and the main-force units). When the strategic...opportunity arose, when the comparison of forces between ourselves and the enemy underwent a_ fundamental change, when the United States was

Mixed Methods Approach to Identify Factors and the Extent to Which They Influence Medical/Surgical Prime Vendor Use

DTIC Science & Technology

2014-03-27

2009). Choosing the Right Type of Rotation in PCA and EFA. JALT Testing & Evaluation Newsletter , 13 (3), 20-25. 102 Bryman , A . (2006). Integrating...FORCE INSTITUTE OF TECHNOLOGY Wright-Patterson Air Force Base, Ohio DISTRIBUTION STATEMENT A . APPROVED FOR PUBLIC RELEASE...official policy or position of the United States Air Force, Department of Defense, or the United States government. This material is declared a work of

Comparison of Transcutaneous Electrical Nerve Stimulation and Cryotherapy for Increasing Quadriceps Activation in Patients With Knee Pathologies.

PubMed

Gabler, Conrad M; Lepley, Adam S; Uhl, Tim L; Mattacola, Carl G

2016-08-01

Proper neuromuscular activation of the quadriceps muscle is essential for maintaining quadriceps (quad) strength and lower-extremity function. Quad activation (QA) failure is a common characteristic observed in patients with knee pathologies, defined as an inability to voluntarily activate the entire alpha-motor-neuron pool innervating the quad. One of the more popular techniques used to assess QA is the superimposed burst (SIB) technique, a force-based technique that uses a supramaximal, percutaneous electrical stimulation to activate all of the motor units in the quad during a maximal, voluntary isometric contraction. Central activation ratio (CAR) is the formula used to calculate QA level (CAR = voluntary force/SIB force) with the SIB technique. People who can voluntarily activate 95% or more (CAR = 0.95-1.0) of their motor units are defined as being fully activated. Therapeutic exercises aimed at improving quad strength in patients with knee pathologies are limited in their effectiveness due to a failure to fully activate the muscle. Within the past decade, several disinhibitory interventions have been introduced to treat QA failure in patients with knee pathologies. Transcutaneous electrical nerve stimulation (TENS) and cryotherapy are sensory-targeted modalities traditionally used to treat pain, but they have been shown to be 2 of the most successful treatments for increasing QA levels in patients with QA failure. Both modalities are hypothesized to positively affect voluntary QA by disinhibiting the motor-neuron pool of the quad. In essence, these modalities provide excitatory afferent stimuli to the spinal cord, which thereby overrides the inhibitory afferent signaling that arises from the involved joint. However, it remains unknown whether 1 is more effective than the other for restoring QA levels in patients with knee pathologies. By knowing the capabilities of each disinhibitory modality, clinicians can tailor treatments based on the rehabilitation goals of their patients. Focused Clinical Question: Is TENS or cryotherapy the more effective disinhibitory modality for treating QA failure (quantified via CAR) in patients with knee pathologies?

United States Air Force Summer Research Program -- 1991. High School Apprenticeship Program (HSAP) Reports, Volume 12: Rome Laboratory, Arnold Engineering Development Plan

DTIC Science & Technology

1991-12-01

UNITED STATES AIR FORCE SUMMER RESEARCH PROGRAM -- 19k’ HIGH SCF-0)OL APPRENTICESHIP PROGRAM (HSAP) REtFOC2TS VOLUME 12 ROME LABORATORY ARNOLD...capacity requirements. In the United States and Japan, it has 1.544 Mbps channels (23B+D), and Europe has 2.048 Mbps channels (30B+D). Both are provided over...because of the standard 64 kbps and the layered protocols. Even though the United States and Europe have different primary access channels, the basic

Motor unit activity when young and old adults perform steady contractions while supporting an inertial load

PubMed Central

Gould, Jeffrey R.; Enoka, Roger M.

2013-01-01

The purpose of the study was to compare the discharge characteristics of biceps brachii motor units of young and old adults when they performed steady, submaximal contractions while the arm supported different inertial loads. Young (28 ± 4 yr; n = 16) and old (75 ± 4 yr; n = 14) adults performed steady contractions with the elbow flexors at target forces set at either small (11.7 ± 4.4% maximum) or large (17.8 ± 6.5% maximum) differences below the recruitment threshold force of the motor unit (n = 40). The task was to maintain an elbow angle at 1.57 rad until the motor unit was recruited and discharged action potentials for ∼120 s. Time to recruitment was longer for the larger target force difference (187 ± 227 s vs. 23 ± 46 s, P < 0.001). Once recruited, motor units discharged action potentials either repetitively or intermittently, with a greater proportion of motor units exhibiting the repetitive pattern for old adults. Discharge rate at recruitment and during the steady contraction was similar for the two target force differences for old adults but was greater for the small target force difference for young adults. Discharge variability was similar at recruitment for the two age groups but less for the old adults during the steady contraction. The greatest difference between the present results and those reported previously when the arm pulled against a rigid restraint was that old adults modulated discharge rate less than young adults across the two contraction intensities for both load types. PMID:23221403

Science and Technology Policymaking: A Primer

DTIC Science & Technology

2009-01-27

survey of developed nations. 4 U.S. Constitution, Article I, Section 8, Clause 8. 5 Jeffrey K. Stine, A History of Science Policy in the United States... History of Science Policy in the United States, 1940-1985 , Report for the House Committee on Science and Technology Task Force on Science Policy...Jeffrey K. Stine, A History of Science Policy in the United States, 1940-1985 , Report for the House Committee on Science and Technology Task Force on

Continuous monitoring bed-level dynamics on an intertidal flat: introducing novel stand-alone high-resolution SED-sensors

NASA Astrophysics Data System (ADS)

Hu, Zhan; Lenting, Walther; van der Wal, Daphne; Bouma, Tjeerd

2015-04-01

Tidal flat morphology is continuously shaped by hydrodynamic force, resulting in highly dynamic bed elevations. The knowledge of short-term bed-level changes is important both for understanding sediment transport processes as well as for assessing critical ecological processes such as e.g. vegetation recruitment chances on tidal flats. Due to the labour involved, manual discontinuous measurements lack the ability to continuously monitor bed-elevation changes. Existing methods for automated continuous monitoring of bed-level changes lack vertical accuracy (e.g., Photo-Electronic Erosion Pin sensor and resistive rod) or limited in spatial application by using expensive technology (e.g., acoustic bed level sensors). A method provides sufficient accuracy with a reasonable cost is needed. In light of this, a high-accuracy sensor (2 mm) for continuously measuring short-term Surface-Elevation Dynamics (SED-sensor) was developed. This SED-sensor makes use of photovoltaic cells and operates stand-alone using internal power supply and data logging system. The unit cost and the labour in deployments is therefore reduced, which facilitates monitoring with a number of units. In this study, the performance of a group of SED-sensors is tested against data obtained with precise manual measurements using traditional Sediment Erosion Bars (SEB). An excellent agreement between the two methods was obtained, indicating the accuracy and precision of the SED-sensors. Furthermore, to demonstrate how the SED-sensors can be used for measuring short-term bed-level dynamics, two SED-sensors were deployed for 1 month at two sites with contrasting wave exposure conditions. Daily bed-level changes were obtained including a severe storm erosion event. The difference in observed bed-level dynamics at both sites was statistically explained by their different hydrodynamic conditions. Thus, the stand-alone SED-sensor can be applied to monitor sediment surface dynamics with high vertical and temporal resolutions, which provides opportunities to pinpoint morphological responses to various forces in a number of environments (e.g. tidal flats, beaches, rivers and dunes).

On Integration and Validation of a Very Low Complexity ATC UWB System for Muscle Force Transmission.

PubMed

Sapienza, Stefano; Crepaldi, Marco; Motto Ros, Paolo; Bonanno, Alberto; Demarchi, Danilo

2016-04-01

The thresholding of Surface ElectroMyoGraphic (sEMG) signals, i.e., Average Threshold Crossing (ATC) technique, reduces the amount of data to be processed enabling circuit complexity reduction and low power consumption. This paper investigates the lowest level of complexity reachable by an ATC system through measurements and in-vivo experiments with an embedded prototype for wireless force transmission, based on asynchronous Impulse-Radio Ultra Wide Band (IR-UWB). The prototype is composed by the acquisition unit, a wearable PCB 23 × 34 mm, which includes a full custom IC integrating a UWB transmitter (chip active silicon area 0.016 mm(2), 1 mW power consumption), and the receiver. The system is completely asynchronous, it acquires a differential sEMG signal, generates the ATC events and triggers a 3.3 GHz IR-UWB transmission. ATC robustness relaxes filters constraints: two passive first order filters have been implemented, bandwidth from 10 Hz up to 1 kHz. Energy needed for the single pulse generation is 30 pJ while the whole PCB consumes 5.65 mW. The pulses radiated by the acquisition unit TX are received by a short-range and low complexity threshold-based 130 nm CMOS IR-UWB receiver with an Ultra Low Power (ULP) baseband unit capable of robustly receiving generic quasi-digital pulse sequences. The acquisition unit have been tested with 10 series of in vivo isometric and isotonic contractions, while the transmission channel with over-the-air and cable measurements obtained with a couple of planar monopole antennas and an integrated 0.004 mm(2) transmitter, the same used for the acquisition unit, with realistic channel conditions. The entire system, acquisition unit and receiver, consumes 15.49 mW.

KSC-08pd1290

NASA Image and Video Library

2008-04-29

VANDENBERG AIR FORCE BASE, Calif. -- At Vandenberg Air Force Base, the OSTM/Jason-2 satellite shipping container is being moved inside the Astrotech processing facility. The OSTM, or Ocean Topography Mission, on the Jason-2 satellite is a follow-on to Jason-1. It will take oceanographic studies of sea surface height into an operational mode for continued climate forecasting research and science and industrial applications. This satellite altimetry data will help determine ocean circulation, climate change and sea-level rise. OSTM is a joint effort by the National Oceanic and Atmospheric Administration, NASA, France’s Centre National d’Etudes Spatiales and the European Meteorological Satellite Organisation. OSTM/Jason-2 will be launched aboard a United Launch Alliance Delta II 7320 from Vandenberg on June 15. Photo credit: NASA/Dan Liberotti

KSC-08pd1292

NASA Image and Video Library

2008-04-29

VANDENBERG AIR FORCE BASE, Calif. -- At Vandenberg Air Force Base, the OSTM/Jason-2 satellite shipping container has been moved inside the Astrotech processing facility. The OSTM, or Ocean Topography Mission, on the Jason-2 satellite is a follow-on to Jason-1. It will take oceanographic studies of sea surface height into an operational mode for continued climate forecasting research and science and industrial applications. This satellite altimetry data will help determine ocean circulation, climate change and sea-level rise. OSTM is a joint effort by the National Oceanic and Atmospheric Administration, NASA, France’s Centre National d’Etudes Spatiales and the European Meteorological Satellite Organisation. OSTM/Jason-2 will be launched aboard a United Launch Alliance Delta II 7320 from Vandenberg on June 15. Photo credit: NASA/Dan Liberotti

KSC-08pd1064

NASA Image and Video Library

2008-04-29

VANDENBERG AIR FORCE BASE, Calif. – The aircraft carrying the OSTM/Jason-2 spacecraft arrives at Vandenberg Air Force Base in California. The OSTM, or Ocean Topography Mission, on the Jason-2 satellite is a follow-on to Jason-1. It will take oceanographic studies of sea surface height into an operational mode for continued climate forecasting research and science and industrial applications. This satellite altimetry data will help determine ocean circulation, climate change and sea-level rise. OSTM is a joint effort by the National Oceanic and Atmospheric Administration, NASA, France’s Centre National d’Etudes Spatiales and the European Meteorological Satellite Organisation. OSTM/Jason-2 will be launched aboard a United Launch Alliance Delta II 7320 from Vandenberg on June 15. Photo credit: NASA/Steve Greenberg, JPL

KSC-08pd1284

NASA Image and Video Library

2008-04-29

VANDENBERG AIR FORCE BASE, Calif. -- At Vandenberg Air Force Base, the truck carrying the OSTM/Jason-2 satellite arrives at the Astrotech processing facility. The OSTM, or Ocean Topography Mission, on the Jason-2 satellite is a follow-on to Jason-1. It will take oceanographic studies of sea surface height into an operational mode for continued climate forecasting research and science and industrial applications. This satellite altimetry data will help determine ocean circulation, climate change and sea-level rise. OSTM is a joint effort by the National Oceanic and Atmospheric Administration, NASA, France’s Centre National d’Etudes Spatiales and the European Meteorological Satellite Organisation. OSTM/Jason-2 will be launched aboard a United Launch Alliance Delta II 7320 from Vandenberg on June 15. Photo credit: NASA/Dan Liberotti

KSC-08pd1291

NASA Image and Video Library

2008-04-29

VANDENBERG AIR FORCE BASE, Calif. -- At Vandenberg Air Force Base, the OSTM/Jason-2 satellite shipping container is being moved inside the Astrotech processing facility. The OSTM, or Ocean Topography Mission, on the Jason-2 satellite is a follow-on to Jason-1. It will take oceanographic studies of sea surface height into an operational mode for continued climate forecasting research and science and industrial applications. This satellite altimetry data will help determine ocean circulation, climate change and sea-level rise. OSTM is a joint effort by the National Oceanic and Atmospheric Administration, NASA, France’s Centre National d’Etudes Spatiales and the European Meteorological Satellite Organisation. OSTM/Jason-2 will be launched aboard a United Launch Alliance Delta II 7320 from Vandenberg on June 15. Photo credit: NASA/Dan Liberotti

KSC-08pd1285

NASA Image and Video Library

2008-04-29

VANDENBERG AIR FORCE BASE, Calif. -- At Vandenberg Air Force Base, the truck carrying the OSTM/Jason-2 satellite arrives at the Astrotech processing facility. The OSTM, or Ocean Topography Mission, on the Jason-2 satellite is a follow-on to Jason-1. It will take oceanographic studies of sea surface height into an operational mode for continued climate forecasting research and science and industrial applications. This satellite altimetry data will help determine ocean circulation, climate change and sea-level rise. OSTM is a joint effort by the National Oceanic and Atmospheric Administration, NASA, France’s Centre National d’Etudes Spatiales and the European Meteorological Satellite Organisation. OSTM/Jason-2 will be launched aboard a United Launch Alliance Delta II 7320 from Vandenberg on June 15. Photo credit: NASA/Dan Liberotti

A Comparison of Classical Force-Fields for Molecular Dynamics Simulations of Lubricants

PubMed Central

Ewen, James P.; Gattinoni, Chiara; Thakkar, Foram M.; Morgan, Neal; Spikes, Hugh A.; Dini, Daniele

2016-01-01

For the successful development and application of lubricants, a full understanding of their complex nanoscale behavior under a wide range of external conditions is required, but this is difficult to obtain experimentally. Nonequilibrium molecular dynamics (NEMD) simulations can be used to yield unique insights into the atomic-scale structure and friction of lubricants and additives; however, the accuracy of the results depend on the chosen force-field. In this study, we demonstrate that the use of an accurate, all-atom force-field is critical in order to; (i) accurately predict important properties of long-chain, linear molecules; and (ii) reproduce experimental friction behavior of multi-component tribological systems. In particular, we focus on n-hexadecane, an important model lubricant with a wide range of industrial applications. Moreover, simulating conditions common in tribological systems, i.e., high temperatures and pressures (HTHP), allows the limits of the selected force-fields to be tested. In the first section, a large number of united-atom and all-atom force-fields are benchmarked in terms of their density and viscosity prediction accuracy of n-hexadecane using equilibrium molecular dynamics (EMD) simulations at ambient and HTHP conditions. Whilst united-atom force-fields accurately reproduce experimental density, the viscosity is significantly under-predicted compared to all-atom force-fields and experiments. Moreover, some all-atom force-fields yield elevated melting points, leading to significant overestimation of both the density and viscosity. In the second section, the most accurate united-atom and all-atom force-field are compared in confined NEMD simulations which probe the structure and friction of stearic acid adsorbed on iron oxide and separated by a thin layer of n-hexadecane. The united-atom force-field provides an accurate representation of the structure of the confined stearic acid film; however, friction coefficients are consistently under-predicted and the friction-coverage and friction-velocity behavior deviates from that observed using all-atom force-fields and experimentally. This has important implications regarding force-field selection for NEMD simulations of systems containing long-chain, linear molecules; specifically, it is recommended that accurate all-atom potentials, such as L-OPLS-AA, are employed. PMID:28773773

A Comparison of Classical Force-Fields for Molecular Dynamics Simulations of Lubricants.

PubMed

Ewen, James P; Gattinoni, Chiara; Thakkar, Foram M; Morgan, Neal; Spikes, Hugh A; Dini, Daniele

2016-08-02

For the successful development and application of lubricants, a full understanding of their complex nanoscale behavior under a wide range of external conditions is required, but this is difficult to obtain experimentally. Nonequilibrium molecular dynamics (NEMD) simulations can be used to yield unique insights into the atomic-scale structure and friction of lubricants and additives; however, the accuracy of the results depend on the chosen force-field. In this study, we demonstrate that the use of an accurate, all-atom force-field is critical in order to; (i) accurately predict important properties of long-chain, linear molecules; and (ii) reproduce experimental friction behavior of multi-component tribological systems. In particular, we focus on n -hexadecane, an important model lubricant with a wide range of industrial applications. Moreover, simulating conditions common in tribological systems, i.e., high temperatures and pressures (HTHP), allows the limits of the selected force-fields to be tested. In the first section, a large number of united-atom and all-atom force-fields are benchmarked in terms of their density and viscosity prediction accuracy of n -hexadecane using equilibrium molecular dynamics (EMD) simulations at ambient and HTHP conditions. Whilst united-atom force-fields accurately reproduce experimental density, the viscosity is significantly under-predicted compared to all-atom force-fields and experiments. Moreover, some all-atom force-fields yield elevated melting points, leading to significant overestimation of both the density and viscosity. In the second section, the most accurate united-atom and all-atom force-field are compared in confined NEMD simulations which probe the structure and friction of stearic acid adsorbed on iron oxide and separated by a thin layer of n -hexadecane. The united-atom force-field provides an accurate representation of the structure of the confined stearic acid film; however, friction coefficients are consistently under-predicted and the friction-coverage and friction-velocity behavior deviates from that observed using all-atom force-fields and experimentally. This has important implications regarding force-field selection for NEMD simulations of systems containing long-chain, linear molecules; specifically, it is recommended that accurate all-atom potentials, such as L-OPLS-AA, are employed.

Analysis of Rawinsonde Spatial Separation for Space Launch Vehicle Applications at the Eastern Range

NASA Technical Reports Server (NTRS)

Decker, Ryan K.

2017-01-01

Space launch vehicles develop day-of-launch steering commands based upon the upper-level atmospheric environments in order to alleviate wind induced structural loading and optimize ascent trajectory. Historically, upper-level wind measurements to support launch operations at the National Aeronautics and Space Administration's (NASA's) Kennedy Space Center co-located on the United States Air Force's Eastern Range (ER) at the Cape Canaveral Air Force Station use high-resolution rawinsondes. One inherent limitation with rawinsondes consists of taking approximately one hour to generate a vertically complete wind profile. Additionally, rawinsonde drift during ascent by the ambient wind environment can result in the balloon being hundreds of kilometers down range, which results in questioning whether the measured winds represent the wind environment the vehicle will experience during ascent. This paper will describe the use of balloon profile databases to statistically assess the drift distance away from the ER launch complexes during rawinsonde ascent as a function of season and discuss an alternative method to measure upper level wind environments in closer proximity to the vehicle trajectory launching from the ER.

Low-level radwaste storage facility at Hope Creek and Salem Generating Stations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oyen, L.C.; Lee, K.; Bravo, R.

Following the January 1, 1993, closure of the radwaste disposal facilities at Beatty, Nevada, and Richland, Washington (to waste generators outside the compact), only Barnwell, South Carolina, is open to waste generators in most states. Barnwell is scheduled to stay open to waste generators outside the Southeast Compact until June 30, 1994. Continued delays in opening regional radwaste disposal facilities have forced most nuclear utilities to consider on-site storage of low-level radwaste. Public Service Electric and Gas Company (PSE G) considered several different radwaste storage options before selecting the design based on the steel-frame and metal-siding building design described inmore » the Electric Power Research Institute's (EPRI's) TR-100298 Vol. 2, Project 3800 report. The storage facility will accommodate waste generated by Salem units 1 and 2 and Hope Creek unit 1 for a 5-yr period and will be located within their common protected area.« less

[Spatio-temporal change of sand-fixing function and its driving forces in desertification control ecological function area of Hunshandake, China].

PubMed

Shen, Lu; Tian, Mei-rong; Gao, Ji-xi; Qian, Jin-ping

2016-01-01

Soil erosion is an important ecological and environmental problem in Hunshandake Desert, and the sand-fixing function determines the degree of ecological security in the entire region. In order to clarify the situation of windbreak and sand fixation in Hunshandake area, and to guide the prevention and treatment of desertification on regional scale, based on the meteorological and remote sensing data, this paper quantitatively analyzed the temporal and spatial pattern of windbreak and sand fixation ability between 2000-2010 by the revised wind erosion equation (RWEQ) model, meanwhile, the driving forces for each county ( or banner) in the functional zone were analyzed with the method of principal component analysis. The results showed that there was a fluctuation of the sand fixing capacity in Hunshandake over time, generally rendering a decline trend. The coniferous forest and grassland had strong windbreak and sand fixation capacity in unit area among the various land categories. In terms of spatial distribution, the windbreak and sand fixation function in western and southeastern region was weak and needed to be strengthened with ecological restoration efforts. Through the study of the social driving forces of each administrative region in the function zone, there were 3 main social driving forces of soil erosion in the administrative functions: the intensity of input-output, the level of economic development and the level of agriculture-husbandry development.

Quantitative attribution of major driving forces on soil organic carbon dynamics

USGS Publications Warehouse

Wu, Yiping; Liu, Shuguang; Tan, Zhengxi

2015-01-01

Soil organic carbon (SOC) storage plays a major role in the global carbon cycle and is affected by many factors including land use/management changes (e.g., biofuel production-oriented changes). However, the contributions of various factors to SOC changes are not well understood and quantified. This study was designed to investigate the impacts of changing farming practices, initial SOC levels, and biological enhancement of grain production on SOC dynamics and to attribute the relative contributions of major driving forces (CO2 enrichment and farming practices) using a fractional factorial modeling design. The case study at a crop site in Iowa in the United States demonstrated that the traditional corn-soybean (CS) rotation could still accumulate SOC over this century (from 4.2 to 6.8 kg C/m2) under the current condition; whereas the continuous-corn (CC) system might have a higher SOC sequestration potential than CS. In either case, however, residue removal could reduce the sink potential substantially. Long-term simulation results also suggested that the equilibrium SOC level may vary greatly (∼5.7 to ∼11 kg C/m2) depending on cropping systems and management practices, and projected growth enhancement could make the magnitudes higher (∼7.8 to ∼13 kg C/m2). Importantly, the factorial design analysis indicated that residue management had the most significant impact (contributing 49.4%) on SOC changes, followed by CO2 Enrichment (37%), Tillage (6.2%), the combination of CO2Enrichment-Residue removal (5.8%), and Fertilization (1.6%). In brief, this study is valuable for understanding the major forces driving SOC dynamics of agroecosystems and informative for decision-makers when seeking the enhancement of SOC sequestration potential and sustainability of biofuel production, especially in the Corn Belt region of the United States.

Initial forces experienced by the anterior and posterior teeth during dental-anchored or skeletal-anchored en masse retraction in vitro.

PubMed

Lee, David; Heo, Giseon; El-Bialy, Tarek; Carey, Jason P; Major, Paul W; Romanyk, Dan L

2017-07-01

To investigate initial forces acting on teeth around the arch during en masse retraction using an in vitro Orthodontic SIMulator (OSIM). The OSIM was used to represent the full maxillary arch in a case wherein both first premolars had been extracted. Dental and skeletal anchorage to a posted archwire and skeletal anchorage to a 10-mm power arm were all simulated. A 0.019 × 0.025-inch stainless steel archwire was used in all cases, and 15-mm light nickel-titanium springs were activated to approximately 150 g on both sides of the arch. A sample size of n = 40 springs were tested for each of the three groups. Multivariate analysis of variance (α = 0.05) was used to determine differences between treatment groups. In the anterior segment, it was found that skeletal anchorage with power arms generated the largest retraction force (P < .001). The largest vertical forces on the unit were generated using skeletal anchorage, followed by skeletal anchorage with power arms, and finally dental anchorage. Power arms were found to generate larger intrusive forces on the lateral incisors and extrusive forces on the canines than on other groups. For the posterior anchorage unit, dental anchorage generated the largest protraction and palatal forces. Negligible forces were measured for both skeletal anchorage groups. Vertical forces on the posterior unit were minimal in all cases (<0.1 N). All retraction methods produced sufficient forces to retract the anterior teeth during en masse retraction. Skeletal anchorage reduced forces on the posterior teeth but introduced greater vertical forces on the anterior teeth.

Paradigm Shifts in Voluntary Force Control and Motor Unit Behaviors with the Manipulated Size of Visual Error Perception

PubMed Central

Chen, Yi-Ching; Lin, Yen-Ting; Chang, Gwo-Ching; Hwang, Ing-Shiou

2017-01-01

The detection of error information is an essential prerequisite of a feedback-based movement. This study investigated the differential behavior and neurophysiological mechanisms of a cyclic force-tracking task using error-reducing and error-enhancing feedback. The discharge patterns of a relatively large number of motor units (MUs) were assessed with custom-designed multi-channel surface electromyography following mathematical decomposition of the experimentally-measured signals. Force characteristics, force-discharge relation, and phase-locking cortical activities in the contralateral motor cortex to individual MUs were contrasted among the low (LSF), normal (NSF), and high scaling factor (HSF) conditions, in which the sizes of online execution errors were displayed with various amplification ratios. Along with a spectral shift of the force output toward a lower band, force output with a more phase-lead became less irregular, and tracking accuracy was worse in the LSF condition than in the HSF condition. The coherent discharge of high phasic (HP) MUs with the target signal was greater, and inter-spike intervals were larger, in the LSF condition than in the HSF condition. Force-tracking in the LSF condition manifested with stronger phase-locked EEG activity in the contralateral motor cortex to discharge of the (HP) MUs (LSF > NSF, HSF). The coherent discharge of the (HP) MUs during the cyclic force-tracking predominated the force-discharge relation, which increased inversely to the error scaling factor. In conclusion, the size of visualized error gates motor unit discharge, force-discharge relation, and the relative influences of the feedback and feedforward processes on force control. A smaller visualized error size favors voluntary force control using a feedforward process, in relation to a selective central modulation that enhance the coherent discharge of (HP) MUs. PMID:28348530

Paradigm Shifts in Voluntary Force Control and Motor Unit Behaviors with the Manipulated Size of Visual Error Perception.

PubMed

Chen, Yi-Ching; Lin, Yen-Ting; Chang, Gwo-Ching; Hwang, Ing-Shiou

2017-01-01

The detection of error information is an essential prerequisite of a feedback-based movement. This study investigated the differential behavior and neurophysiological mechanisms of a cyclic force-tracking task using error-reducing and error-enhancing feedback. The discharge patterns of a relatively large number of motor units (MUs) were assessed with custom-designed multi-channel surface electromyography following mathematical decomposition of the experimentally-measured signals. Force characteristics, force-discharge relation, and phase-locking cortical activities in the contralateral motor cortex to individual MUs were contrasted among the low (LSF), normal (NSF), and high scaling factor (HSF) conditions, in which the sizes of online execution errors were displayed with various amplification ratios. Along with a spectral shift of the force output toward a lower band, force output with a more phase-lead became less irregular, and tracking accuracy was worse in the LSF condition than in the HSF condition. The coherent discharge of high phasic (HP) MUs with the target signal was greater, and inter-spike intervals were larger, in the LSF condition than in the HSF condition. Force-tracking in the LSF condition manifested with stronger phase-locked EEG activity in the contralateral motor cortex to discharge of the (HP) MUs (LSF > NSF, HSF). The coherent discharge of the (HP) MUs during the cyclic force-tracking predominated the force-discharge relation, which increased inversely to the error scaling factor. In conclusion, the size of visualized error gates motor unit discharge, force-discharge relation, and the relative influences of the feedback and feedforward processes on force control. A smaller visualized error size favors voluntary force control using a feedforward process, in relation to a selective central modulation that enhance the coherent discharge of (HP) MUs.

China's rise as a major contributor to science and technology.

PubMed

Xie, Yu; Zhang, Chunni; Lai, Qing

2014-07-01

In the past three decades, China has become a major contributor to science and technology. China now employs an increasingly large labor force of scientists and engineers at relatively high earnings and produces more science and engineering degrees than the United States at all levels, particularly bachelor's. China's research and development expenditure has been rising. Research output in China has been sharply increasing since 2002, making China the second largest producer of scientific papers after the United States. The quality of research by Chinese scientists has also been improving steadily. However, China's rise in science also faces serious difficulties, partly attributable to its rigid, top-down administrative system, with allegations of scientific misconduct trending upward.

United States Air Force Summer Research Program -- 1993. Volume 13. Phillips Laboratory

DTIC Science & Technology

1993-12-01

Research Kirtland Air Force Base, Albuquerque, NM August 1993 14-1 My Summer Apprenticeship At Kirtland Air Force Base, Phillips Laboratory Andrea Garcia...AFOSR Summer Research Program Phillips Laboratory Sponsored By: Air Force Office of Scientific Research Kirtland Air Force Base, Albuquerque, NM... Phillips Laboratory Sponsored by: Air

The United States Air Force Reserve Officer Training Corps: Looking to the Future

DTIC Science & Technology

1991-03-04

Brigadier General Robin G. Tornow Commandant, Air Force ROTC (Note 25) Over the years, Air Force ROTC has developed many strong points. Paramount among...maintaining a leaner and more capable force for the future. Brigadier General Robin G. Tornow Commandant, Air Force ROTC (Note 35) This alternative

The Faith of the Force: The Strategic Implications of Religion in the United States Air Force

DTIC Science & Technology

2012-06-01

human beings developing the capacity for telepathy through vibrations in molars. My wife told me it was the dumbest thing I’d ever said. While I am...vibrational telepathy . ABSTRACT This study examines the strategic implications of religion in the United States Air Force. While religion in the...version of the city on the hill analogy: “As the earliest settlers arrived on the shores of Boston and Salem and Plymouth, they dreamed of building a

Recuiting, Advertising and Marketing Strategies in All-Volunteer Force Nations: Case Studies of Canada, Australia, the United Kingdom, and the United States

DTIC Science & Technology

2011-12-01

Vass 2007; Australian Defence Force 2011). The mining industry is considered a direct competitor, as it has experienced rapid employment growth for...military must compete with the transportation, mining , engineering, construction and health sectors (Defence Force Recruiting 2010b). The Navy met many...national team, the Opals . The sponsorship was timed to promote the launching of the defencejobs website. This effort attempted to project the ADF brand

Government Competitive Test Utility Tactical Transport Aircraft System (UTTAS). Sikorsky YUH-60A Helicopter

DTIC Science & Technology

1976-11-01

Box 209, St. Louis, Missouri 63166. UNITED STATES ARMY AVIATION ENGINEERING FLIGHT ACTIVITY EDWARDS AIR FORCE BASE, CALIFORNIA 93523 81 9 18 0 8,L...ELEMENT. PROJECT. TASKAR EA A WORK UNIT "UMBERS US ARMY AVIATION ENGINEERING FLIGHT ACTIV IU EDWARDS AIR FORCE BASE. CALIFORNIA 93523 68-T-UA022-0-68-EC...It. CONTROLLI~NG OFFICE NAME AND ADDRESS 12. REPORT DATE US ARMY AVIATION ENGINEERING FLIGHT ACTIVITY NOVEMBER 1976 EDWARDS AIR FORCE BASE

The Implementation of the Responsibility to Protect (R2P) Norms by the African Standby Force in Sub-Saharan Africa

DTIC Science & Technology

2017-06-09

S) Major Augustin Hodali 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES...support of many individuals and organizations . First, I am whole-heartedly thankful to the Rwandan Government and particularly the Rwanda Defense Forces...African Standby Force AU African Union DRC Democratic Republic of the Congo MONUSCO United Nations Organization Stabilization Mission in the Democratic

From ’Battle’ to the ’Battle of Ideas’: The Meaning and Misunderstanding of Information Operations

DTIC Science & Technology

2010-12-10

significant effort US forces placed on finding NVA units. As a result, Army forces could rapidly and unexpectedly, concentrate firepower. However, air...military success of American forces during the Gulf War and the disintegration of the Warsaw pact (and with it the Cold War) would lead to significant...This was because “the United States did not come close to its potential to move the most useful information rapidly to those who needed it most

Independent Auditors Report on the Air Force Working Capital Fund FY 2015 and FY 2014 Basic Financial Statements for United States Air Force Agency Financial Report 2015

DTIC Science & Technology

2015-11-09

missile warning, weather and intelligence warfighting support. AFSPC operates sensors that provide direct attack warning and assessment to U.S...toughness combinations. AFRL conducted low-speed wind tunnel tests of 9%-scale model completed at NASA Langley Research Center (LaRC); data validated... wireless mobile monitoring capability designed for dismounted Pararescue Jumpers (PJ) called United States Air Force 89 Battlefield Airmen Trauma

APPLYING LESSONS LEARNED FROM THE UNITED STATES SPECIAL OPERATIONS COMMAND’S HUMAN PERFORMANCE PROGRAM TO THE UNITED STATES AIR FORCES COMPREHENSIVE AIRMAN FITNESS

DTIC Science & Technology

2016-04-01

implementation, focusing physical training on the mission specific requirements of the individual similar to an athletic sports model, increasing access to...initiative as a mechanism to help maintain the resiliency, health, and welfare of its force.1 As Air Force Instruction (AFI) 90-506 states, the strategy ...implementation of Tactical Athlete Programs, which provide tailored workout plans and nutrition education that prepare service members to meet the physical

Changes in force, surface and motor unit EMG during post-exercise development of low frequency fatigue in vastus lateralis muscle.

PubMed

de Ruiter, C J; Elzinga, M J H; Verdijk, P W L; van Mechelen, W; de Haan, A

2005-08-01

We investigated the effects of low frequency fatigue (LFF) on post-exercise changes in rectified surface EMG (rsEMG) and single motor unit EMG (smuEMG) in vastus lateralis muscle (n = 9). On two experimental days the knee extensors were fatigued with a 60-s-isometric contraction (exercise) at 50% maximal force capacity (MFC). On the first day post-exercise (15 s, 3, 9, 15, 21 and 27 min) rsEMG and electrically-induced (surface stimulation) forces were investigated. SmuEMG was obtained on day two. During short ramp and hold (5 s) contractions at 50% MFC, motor unit discharges of the same units were followed over time. Post-exercise MFC and tetanic force (100 Hz stimulation) recovered to about 90% of the pre-exercise values, but recovery with 20 Hz stimulation was less complete: the 20-100 Hz force ratio (mean +/- SD) decreased from 0.65+/-0.06 (pre-exercise) to 0.56+/-0.04 at 27 min post-exercise (P<0.05), indicative of LFF. At 50% MFC, pre-exercise rsEMG (% pre-exercise maximum) and motor unit discharge rate were 51.1 +/- 12.7% and 14.1 +/- 3.7 (pulses per second; pps) respectively, 15 s post-exercise the respective values were 61.4 +/- 15.4% (P<0.05) and 13.2 +/- 5.6 pps (P>0.05). Thereafter, rsEMG (at 50% MFC) remained stable but motor unit discharge rate significantly increased to 17.7 +/- 3.9 pps 27 min post-exercise. The recruitment threshold decreased (P<0.05) from 27.7 +/- 6.6% MFC before exercise to 25.2 +/- 6.7% 27 min post-exercise. The increase in discharge rate was significantly greater than could be expected from the decrease in recruitment threshold. Thus, post-exercise LFF was compensated by increased motor unit discharge rates which could only partly be accounted for by the small decrease in motor unit recruitment threshold.

Scientific and Technological Achievements, 1946-2011, of the AFRL Electromagnetics Technology Division (AFRL/RYH) and Its Progenitors

DTIC Science & Technology

2012-07-01

AFRL /RYH) Sensors Directorate Air Force Research Laboratory Wright-Patterson Air Force ...Lossless Acoustic Monopoles, Electric Dipoles, and Magnetodielectric Spheres, Air Force Research Laboratory in-house report AFRL -SN-HS-TR-2006-0039... FORCE RESEARCH LABORATORY SENSORS DIRECTORATE WRIGHT-PATTERSON AIR FORCE BASE, OH 45433-7320 AIR FORCE MATERIEL COMMAND UNITED

AFWL Standards for Scientific and Technical Reports.

DTIC Science & Technology

1980-04-01

Air Force Weapons Laboratory , Kirtland Air Force Base, New Mexico, under...PROGRAM ELEMEN T PROJECT TASK AREA & WORK UNIT NUMBERS Air Force Weapons Laboratory (SUR) Kirtland Air Force Base, NM 87117 62601F/99930000 I. CONTROLLING...OFFICE NAME AND ADDRESS 12 REPORT DATE Air Force Weapons Laboratory (SUR) April 1980 Kirtland Air Force Base, NM 87117 13. NUMBER OF PAGES 72

Forced phase-locked states and information retrieval in a two-layer network of oscillatory neurons with directional connectivity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kazantsev, Victor; Pimashkin, Alexey; Department of Neurodynamics and Neurobiology, Nizhny Novgorod State University, 23 Gagarin Ave., 603950 Nizhny Novgorod

We propose two-layer architecture of associative memory oscillatory network with directional interlayer connectivity. The network is capable to store information in the form of phase-locked (in-phase and antiphase) oscillatory patterns. The first (input) layer takes an input pattern to be recognized and their units are unidirectionally connected with all units of the second (control) layer. The connection strengths are weighted using the Hebbian rule. The output (retrieved) patterns appear as forced-phase locked states of the control layer. The conditions are found and analytically expressed for pattern retrieval in response on incoming stimulus. It is shown that the system is capablemore » to recover patterns with a certain level of distortions or noises in their profiles. The architecture is implemented with the Kuramoto phase model and using synaptically coupled neural oscillators with spikes. It is found that the spiking model is capable to retrieve patterns using the spiking phase that translates memorized patterns into the spiking phase shifts at different time scales.« less

The United States Special Operations Command Civil Military Engagement Program - A Model for Military-Interagency Low Cost / Small Footprint Activities

DTIC Science & Technology

2014-05-02

Interagency Coordination Centers (JIACs), Interagency Task Forces ( IATFs ) are found within GCCs and subordinate military units in an attempt to bridge...Interagency Tasks Forces ( IATFs ) that exist at each Geographic Combatant Command (GCC). Rather, this chapter serves to highlight the Civil Military

The United States Marine Corps: The 911 Force in the Post-9/11 World

DTIC Science & Technology

2007-02-23

increased efforts to engage narco-crime syndicate threats such as the Revolutionary Armed Forces of Columbia (FARC), which is largely responsible for...discord. The United States should view this as an opportunity. As New York Times columnist James Traub notes, If we believe that a model of development

Multidecadal Changes in Near-Global Cloud Cover and Estimated Cloud Cover Radiative Forcing

NASA Technical Reports Server (NTRS)

Norris, Joel

2005-01-01

The first paper was Multidecadal changes in near-global cloud cover and estimated cloud cover radiative forcing, by J. R. Norris (2005, J. Geophys. Res. - Atmos., 110, D08206, doi: lO.l029/2004JD005600). This study examined variability in zonal mean surface-observed upper-level (combined midlevel and high-level) and low-level cloud cover over land during 1971-1 996 and over ocean during 1952-1997. These data were averaged from individual synoptic reports in the Extended Edited Cloud Report Archive (EECRA). Although substantial interdecadal variability is present in the time series, long-term decreases in upper-level cloud cover occur over land and ocean at low and middle latitudes in both hemispheres. Near-global upper-level cloud cover declined by 1.5%-sky-cover over land between 1971 and 1996 and by 1.3%-sky-cover over ocean between 1952 and 1997. Consistency between EECRA upper-level cloud cover anomalies and those from the International Satellite Cloud Climatology Project (ISCCP) during 1984-1 997 suggests the surface-observed trends are real. The reduction in surface-observed upper-level cloud cover between the 1980s and 1990s is also consistent with the decadal increase in all-sky outgoing longwave radiation reported by the Earth Radiation Budget Satellite (EMS). Discrepancies occur between time series of EECRA and ISCCP low-level cloud cover due to identified and probable artifacts in satellite and surface cloud data. Radiative effects of surface-observed cloud cover anomalies, called "cloud cover radiative forcing (CCRF) anomalies," are estimated based on a linear relationship to climatological cloud radiative forcing per unit cloud cover. Zonal mean estimated longwave CCRF has decreased over most of the globe. Estimated shortwave CCRF has become slightly stronger over northern midlatitude oceans and slightly weaker over northern midlatitude land areas. A long-term decline in the magnitude of estimated shortwave CCRF occurs over low-latitude land and ocean, but comparison with EMS all-sky reflected shortwave radiation during 1985-1997 suggests this decrease may be underestimated.

Department of Defense Manpower Requirements Report, FY 1985. Volume III. Force Readiness Report.

DTIC Science & Technology

1984-02-01

forces are made up of a variety of different types of units. Each unit has associated with it a collection of positions that must be filled by...available inventory, accession arid separation predictions, fiscal constraints, manpower ceilings--the list seems endless. The collection of positions that...units complete collective training and remain in FORSCOM for 18 months if deploying to a long-tour area such as Europe; or for 24 months if pre- paring

Science and Technology Policymaking: A Primer

DTIC Science & Technology

2008-04-22

the federal government CRS-2 4 U.S. Constitution, Article I, Section 8, Clause 8. 5 Jeffrey K. Stine, A History of Science Policy in the United States...Stine, A History of Science Policy in the United States, 1940-1985 , Report for the House Committee on Science and Technology Task Force on Science...K. Stine, A History of Science Policy in the United States, 1940-1985 , Report for the House Committee on Science and Technology Task Force on

Understanding Revenge Pornography: A National Survey of Police Officers and Staff in England and Wales.

PubMed

Bond, Emma; Tyrrell, Katie

2018-02-01

Online abuse, facilitated via social media and mobile technologies, has recently attracted considerable academic attention. The nonconsensual sharing of intimate images-revenge pornography-can have a devastating effect on victims, is a global problem, and constitutes interpersonal violence. The national helpline in the United Kingdom has now received over 7,000 calls. In the United Kingdom, new legislation making revenge pornography a crime was introduced in 2014, yet the police do not always respond appropriately to victims. This article presents the findings of a national online survey of police understanding of revenge pornography, undertaken in the United Kingdom in March 2017. The study set out to investigate police knowledge of revenge pornography legislation, their confidence in responding to cases of revenge pornography, and what level of training they had received. A total of 783 members of the police force responded to the survey and, to the authors' knowledge, this the first study to seek to quantify the understanding of revenge pornography by police officers and staff in England and Wales. The findings suggest that the police in the United Kingdom have a limited understanding of revenge pornography legislation and lack confidence both in investigating cases and in effectively responding to victims. The implications of the study demonstrate that there is an urgent need for training across police forces to ensure that cases of revenge pornography are appropriately responded to, victims are safeguarded, and offenders brought to justice.

Mathematical modeling of the flow field and particle motion in a rotating bioreactor at unit gravity and microgravity

NASA Technical Reports Server (NTRS)

Boyd, Ernest J.

1990-01-01

The biotechnology group at NASA Johnson Space Center is developing systems for culturing mammalian cells that stimulate some aspect of microgravity and provide a low shear environment for microgravity-based studies on suspension and anchorage dependent cells. The design of these vessels for culturing cells is based on the need to suspend cells and aggregates of cells and microcarrier beads continually in the culturing medium. The design must also provide sufficient circulation for adequate mass transfer of nutrients to the cells and minimize the total force on the cells. Forces, resulting from sources such as hydrodynamic fluid shear and collisions of cells and walls of the vessels, may damage delicate cells and degrade the formation of three dimensional structures. This study examines one particular design in both unit gravity and microgravity based on two concentric cylinders rotating in the same direction at different speeds to create a Couette flow between them. A numerical simulation for the flow field and the trajectories of particles in the vessel. The flow field for the circulation of the culturing medium is modeled by the Navier-Stokes equations. The forces on a particle are assumed to be drag from the fluid's circulation, buoyancy from the gravitational force and centrifugal force from the rotation of the vessel. The problem requires first solving the system of partial differential equations for the fluid flow by a finite difference method and then solving the system of ordinary differential equations for the trajectories by Gear's stiff method. Results of the study indicate that the trajectories in unit gravity and microgravity are very similar except for small spatial deviations on the fast time scale in unit gravity. The total force per unit cross sectional area on a particle in microgravity, however, is significantly smaller than the corresponding value in unit gravity, which is also smaller than anticipated. Hence, this study indicates that this design for a bioreactor with optimal rates of rotation can provide a good environment for culturing cells in microgravity with adequate circulation and minimal force on the cells.

NASA and the United States educational system - Outreach programs in aeronautics, space science, and technology

NASA Technical Reports Server (NTRS)

Owens, Frank C.

1990-01-01

The role of NASA in developing a well-educated American work force is addressed. NASA educational programs aimed at precollege students are examined, including the NASA Spacemobile, Urban Community Enrichment Program, and Summer High School Apprenticeship Program. NASA workshops and programs aimed at helping teachers develop classroom curriculum materials are described. Programs aimed at college and graduate-level students are considered along with coordination efforts with other federal agencies and with corporations.

Battle on the Bookshelves: History, Desert Storm, and the United States Armed Forces

DTIC Science & Technology

2004-06-17

impacted on the outcome of the war, ranging from superior American technology to flagging Iraqi morale, each of the armed services is free to claim...though decidedly more subtle, could 5 have an equally large impact at the strategic level. For instance, if a service succeeds in overstating its...official accounts of a campaign. Therefore, as part o this work, it is necessary to determine the impact of organizational culture on the observed

Smoking in the United States Air Force: Trends, Most Prevalent Diseases and their Association with Cost

DTIC Science & Technology

2011-09-01

phenomenon that affects various fields of human activity. Smoking is not merely a personal choice at the individual level, but affects society and thereby...not influence human health as much as smoking tobacco. However, smokeless tobacco has been found to 6 be more addictive than smoking tobacco and...around the world focusing on smoking and the harmful effects on human health and, consequently, on society. The World Health Organization (WHO) has

A Comparison of Nurse Staffing Methods Used by the United States Air Force and Selected Civilian Hospitals

DTIC Science & Technology

1989-09-01

X1 = average days of bed occupancy by medical and surgical patients/month lexcluding pediatric, nursery, neonatal intensive care, psychiatric and...one for a neonatal intensive nursery. The residency teaching program additive is identical to the one used in AFMS 5206. The neonatal intensive nursery...additive is quite straightforward: if the facility nas a Neonatal Level Ii nursery, a constant requirement for twelve additional personnel is added to

Knowledge Transformation in the United States Air Force Civil Engineer Career Field: A System Dynamics Approach

DTIC Science & Technology

2010-03-01

Review and recommend or approve contracts and cost estimates. Compute load and grade requirements, water flow rates , and material stress factors to...classified into one of ten standard behavioral categories. While the exact rate and value of the behavior may vary, the underlying infrastructure they...it at some rate Y. However, if the same individual increases their knowledge to X*2, retaining that level of knowledge will be more difficult

United States-Vietnam Relations 1945-1967, Study Prepared by the Department of Defense, Book 2 of 12

DTIC Science & Technology

1971-01-01

status of other semi-military and police forces.... 29. South Vietnam’s mobilisable manpower pool is estimated at 1,500,000 physically fit...con- ferees themselves, who postulated an ideal political settlement incom- patible with the physical and psychological dismemberment of Vietnam...level where people are fighting and working, and in our new scale of values it is those who participate physically and selflessly in the fight

Orbiting Carbon Observatory-2 (OCO-2)

NASA Image and Video Library

2014-06-29

The upper levels of the launch gantry, surrounding the United Launch Alliance Delta II rocket with the Orbiting Carbon Observatory-2 (OCO-2) satellite onboard, are seen at the Space Launch Complex 2, Sunday, June 29, 2014, Vandenberg Air Force Base, Calif. OCO-2 will measure the global distribution of carbon dioxide, the leading human-produced greenhouse gas driving changes in Earth’s climate. OCO-2 is set for a July 1, 2014 launch. Photo Credit: (NASA/Bill Ingalls)

A Question of Equity: Women and the Glass Ceiling in the Federal Government. A Special Study. A Report to the President and the Congress of the United States.

ERIC Educational Resources Information Center

Merit Systems Protection Board, Washington, DC.

An investigation of the process for career progression in the federal white-collar work force examined the nature and extent of any barriers women may confront in that process. It included data from three sources: U.S. Office of Personnel Management's Central Personnel Data File; 19 focus groups with 144 senior level and senior executive men and…

Is Soleus Muscle-Tendon-Unit Behavior Related to Ground-Force Application During the Sprint Start?

PubMed

Schrödter, Erik; Brüggemann, Gert-Peter; Willwacher, Steffen

2017-04-01

To describe the stretch-shortening behavior of ankle plantar-flexing muscle-tendon units (MTUs) during the push-off in a sprint start. Fifty-four male (100-m personal best: 9.58-12.07 s) and 34 female (100-m personal best: 11.05-14.00 s) sprinters were analyzed using an instrumented starting block and 2-dimensional high-speed video imaging. Analysis was performed separately for front and rear legs, while accounting for block obliquities and performance levels. The results showed clear signs of a dorsiflexion in the upper ankle joint (front block 15.8° ± 7.4°, 95% CI 13.2-18.2°; rear block 8.0° ± 5.7°, 95% CI 6.4-9.7°) preceding plantar flexion. When observed in their natural block settings, the athletes' block obliquity did not significantly affect push-off characteristics. It seems that the stretch-shortening-cycle-like motion of the soleus MTU has an enhancing influence on push-off force generation. This study provides the first systematic observation of ankle-joint stretch-shortening behavior for sprinters of a wide range of performance levels. The findings highlight the importance of reactive-type training for the improvement of starting performance. Nonetheless, future studies need to resolve the independent contributions of tendinous and muscle-fascicle structures to overall MTU performance.

[Intensive care within the context of military long-distance transport].

PubMed

Hossfeld, B; Rohowsky, B; Rödig, E; Lampl, L

2004-05-01

Due to the changed task spectrum of the German Federal Armed Forces with participation in international deployments for UN and NATO the concept of Aeromedical Evacuation (MedEvac) gained a new quality for the Air Force as well as for the Medical Corps. The transport of mostly severely injured or critically ill patients requires both, medical equipment which has to be permanently adapted to the national standard, and qualified intensive-care-personnel. At present, the aircrafts used for such deployments are four C-160 Transall, one CL-601 Challenger and two Airbus A310, which, if necessary, can be equipped with one or more intensive-care "patient transportation units" (PTU). Contrary to the two other aircrafts, the CL-601 Challenger is only equipped for the intensive-care transport of one individual patient. The PTU corresponds to the technical equipment of the intensive care unit of a level-1-trauma centre and ensures an intensive-care therapy on highest level also during longer transportation. The work with this equipment, the characteristics of the long-distance air transport and the special situation of the military deployment causes special demands on the qualifications of the assigned personnel. Primarily planned for the repatriation of injured or ill soldiers, in the mean time, this concept is also essential for the medevac of civilian victims after mass casualties worldwide.

Altered motor unit discharge patterns in paretic muscles of stroke survivors assessed using surface electromyography.

PubMed

Hu, Xiaogang; Suresh, Aneesha K; Rymer, William Z; Suresh, Nina L

2016-08-01

Hemispheric stroke survivors often show impairments in voluntary muscle activation. One potential source of these impairments could come from altered control of muscle, via disrupted motor unit (MU) firing patterns. In this study, we sought to determine whether MU firing patterns are modified on the affected side of stroke survivors, as compared with the analogous contralateral muscle. Using a novel surface electromyogram (EMG) sensor array, coupled with advanced template recognition software (dEMG) we recorded surface EMG signals over the first dorsal interosseous (FDI) muscle on both paretic and contralateral sides. Recordings were made as stroke survivors produced isometric index finger abductions over a large force range (20%-60% of maximum). Utilizing the dEMG algorithm, MU firing rates, recruitment thresholds, and action potential amplitudes were estimated for concurrently active MUs in each trial. Our results reveal significant changes in the firing rate patterns in paretic FDI muscle, in that the discharge rates, characterized in relation to recruitment force threshold and to MU size, were less clearly correlated with recruitment force than in contralateral FDI muscles. Firing rates in the affected muscle also did not modulate systematically with the level of voluntary muscle contraction, as would be expected in intact muscles. These disturbances in firing properties also correlated closely with the impairment of muscle force generation. Our results provide strong evidence of disruptions in MU firing behavior in paretic muscles after a hemispheric stroke, suggesting that modified control of the spinal motoneuron pool could be a contributing factor to muscular weakness in stroke survivors.

Altered motor unit discharge patterns in paretic muscles of stroke survivors assessed using surface electromyography

NASA Astrophysics Data System (ADS)

Hu, Xiaogang; Suresh, Aneesha K.; Rymer, William Z.; Suresh, Nina L.

2016-08-01

Objective. Hemispheric stroke survivors often show impairments in voluntary muscle activation. One potential source of these impairments could come from altered control of muscle, via disrupted motor unit (MU) firing patterns. In this study, we sought to determine whether MU firing patterns are modified on the affected side of stroke survivors, as compared with the analogous contralateral muscle. Approach. Using a novel surface electromyogram (EMG) sensor array, coupled with advanced template recognition software (dEMG) we recorded surface EMG signals over the first dorsal interosseous (FDI) muscle on both paretic and contralateral sides. Recordings were made as stroke survivors produced isometric index finger abductions over a large force range (20%-60% of maximum). Utilizing the dEMG algorithm, MU firing rates, recruitment thresholds, and action potential amplitudes were estimated for concurrently active MUs in each trial. Main results. Our results reveal significant changes in the firing rate patterns in paretic FDI muscle, in that the discharge rates, characterized in relation to recruitment force threshold and to MU size, were less clearly correlated with recruitment force than in contralateral FDI muscles. Firing rates in the affected muscle also did not modulate systematically with the level of voluntary muscle contraction, as would be expected in intact muscles. These disturbances in firing properties also correlated closely with the impairment of muscle force generation. Significance. Our results provide strong evidence of disruptions in MU firing behavior in paretic muscles after a hemispheric stroke, suggesting that modified control of the spinal motoneuron pool could be a contributing factor to muscular weakness in stroke survivors.

The impact of hepatitis C on labor force participation, absenteeism, presenteeism and non-work activities.

PubMed

DiBonaventura, Marco daCosta; Wagner, Jan-Samuel; Yuan, Yong; L'Italien, Gilbert; Langley, Paul; Ray Kim, W

2011-01-01

Between 2.7 and 3.9 million people are currently infected with the hepatitis C virus (HCV) in the United States. Although many studies have investigated the impact of HCV on direct healthcare costs, few studies have estimated the indirect costs associated with the virus using a nationally-representative dataset. Using data from the 2009 United States (US) National Health and Wellness Survey, patients who reported a hepatitis C diagnosis (n = 695) were compared to controls on labor force participation, productivity loss, and activity impairment after adjusting for demographics, health risk behaviors, and comorbidities. All analyses applied sampling weights to project to the population. Patients with HCV were significantly less likely to be in the labor force than controls and reported significantly higher levels of absenteeism (4.88 vs. 3.03%), presenteeism (16.69 vs. 13.50%), overall work impairment (19.40 vs.15.35%), and activity impairment (25.01 vs. 21.78%). A propensity score matching methodology replicated many of these findings. While much of the work on HCV has focused on direct costs, our results suggest indirect costs should not be ignored when quantifying the societal burden of HCV. To our knowledge, this is the first study which has utilized a large, nationally-representative data source for identifying the impact of HCV on labor force participation and work and activity impairment using both a propensity-score matching and a regression modeling framework. All data were patient-reported (including HCV diagnosis and work productivity), which could have introduced some subjective biases.

Management and Oversight of Services Acquisition Within the United States Air Force

DTIC Science & Technology

2008-12-01

Air Mobility Command AFDW Air Force District of Washington AFSPC Air Force Space Command AT&L Acquisition Technologies and Logistics CPM ...were commonly performed in industry. The types of services included advertising for Navy recruitment, custodial services on Air Force bases, and on

32 CFR 855.1 - Policy.

Code of Federal Regulations, 2013 CFR

2013-07-01

... of Air Force airfields in foreign countries will be subject to US Federal laws and regulations that... Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE AIRCRAFT CIVIL AIRCRAFT USE OF UNITED STATES AIR FORCE AIRFIELDS General Provisions § 855.1 Policy. The Air Force establishes and uses its...

32 CFR 855.1 - Policy.

Code of Federal Regulations, 2011 CFR

2011-07-01

... of Air Force airfields in foreign countries will be subject to US Federal laws and regulations that... Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE AIRCRAFT CIVIL AIRCRAFT USE OF UNITED STATES AIR FORCE AIRFIELDS General Provisions § 855.1 Policy. The Air Force establishes and uses its...

32 CFR 855.1 - Policy.

Code of Federal Regulations, 2012 CFR

2012-07-01

... of Air Force airfields in foreign countries will be subject to US Federal laws and regulations that... Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE AIRCRAFT CIVIL AIRCRAFT USE OF UNITED STATES AIR FORCE AIRFIELDS General Provisions § 855.1 Policy. The Air Force establishes and uses its...

32 CFR 855.1 - Policy.

Code of Federal Regulations, 2014 CFR

2014-07-01

... of Air Force airfields in foreign countries will be subject to US Federal laws and regulations that... Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE AIRCRAFT CIVIL AIRCRAFT USE OF UNITED STATES AIR FORCE AIRFIELDS General Provisions § 855.1 Policy. The Air Force establishes and uses its...

48 CFR 225.7403 - Antiterrorism/force protection.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Antiterrorism/force protection. 225.7403 Section 225.7403 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS... United States 225.7403 Antiterrorism/force protection. ...

Design and performance evaluation of a master controller for endovascular catheterization.

PubMed

Guo, Jin; Guo, Shuxiang; Tamiya, Takashi; Hirata, Hideyuki; Ishihara, Hidenori

2016-01-01

It is difficult to manipulate a flexible catheter to target a position within a patient's complicated and delicate vessels. However, few researchers focused on the controller designs with much consideration of the natural catheter manipulation skills obtained from manual catheterization. Also, the existing catheter motion measurement methods probably lead to the difficulties in designing the force feedback device. Additionally, the commercially available systems are too expensive which makes them cost prohibitive to most hospitals. This paper presents a simple and cost-effective master controller for endovascular catheterization that can allow the interventionalists to apply the conventional pull, push and twist of the catheter used in current practice. A catheter-sensing unit (used to measure the motion of the catheter) and a force feedback unit (used to provide a sense of resistance force) are both presented. A camera was used to allow a contactless measurement avoiding additional friction, and the force feedback in the axial direction was provided by the magnetic force generated between the permanent magnets and the powered coil. Performance evaluation of the controller was evaluated by first conducting comparison experiments to quantify the accuracy of the catheter-sensing unit, and then conducting several experiments to evaluate the force feedback unit. From the experimental results, the minimum and the maximum errors of translational displacement were 0.003 mm (0.01 %) and 0.425 mm (1.06 %), respectively. The average error was 0.113 mm (0.28 %). In terms of rotational angles, the minimum and the maximum errors were 0.39°(0.33 %) and 7.2°(6 %), respectively. The average error was 3.61°(3.01 %). The force resolution was approximately 25 mN and a maximum current of 3A generated an approximately 1.5 N force. Based on analysis of requirements and state-of-the-art computer-assisted and robot-assisted training systems for endovascular catheterization, a new master controller with force feedback interface was proposed to maintain the natural endovascular catheterization skills of the interventionalists.

Review of metamorphic and kinematic data from Internal Crystalline Massifs (Western Alps): PTt paths and exhumation history

NASA Astrophysics Data System (ADS)

Gasco, Ivano; Gattiglio, Marco; Borghi, Alessandro

2013-01-01

Detailed geological mapping combined with micro-structural and petrological investigation allowed to clarify the tectono-metamorphic relationships between continental and oceanic units transition in the Penninic domain of the Western Alps. The three study areas (Gressoney, Orco and Susa sections) take into consideration the same structural level across the axial metamorphic belt of the Western Italian Alps, i.e., a geological section across the Internal Crystalline Massifs vs Piedmont Zone boundary. The units outcropping in these areas can be grouped into two Tectonic Elements according to their tectono-metamorphic evolution. The Lower Tectonic Element (LTE) consists of the Internal Crystalline Massifs and the Lower Piedmont Zone (Zermatt-Saas like units), both showing well preserved eclogite facies relics. Instead, the Upper Tectonic Element (UTE) consists of the Upper Piedmont Zone (Combin like units) lacking evidence of eclogite facies relics. In the Lower Tectonic Element two main Alpine tectono-metamorphic stages were identified: M1/D1 developed under eclogite facies conditions and M2/D2 is related to the development of the regional foliation under greenschist to epidote-albite amphibolite facies conditions. In the Upper Tectonic Element the metamorphic stage M1/D1 developed under bluschist to greenschist facies conditions and M2/D2 stage under greenschist facies conditions. These two Tectonic Elements are separated by a tectonic contact of regional importance generally developed along the boundary between the Lower and the Upper Piedmont zone under greenschist facies conditions. PT data compared to geochronology indicate that the first exhumation of ICM can be explained by buoyancy forces acting along the subduction channel that occurred during the tectonic coupling between the continental and oceanic eclogite units. These buoyancy forces vanished at the base of the crust where the density difference between the subducted crustal units and the surroundings rocks is too low. A stage where compression prevails on the previous exhumation followed, which leads to the development of the regional foliation under greenschist to amphibolite facies metamorphic conditions. Further exhumation occurred after the M2/D2 stage at shallower crustal levels along conjugated shear zones leading to the development of a composite axial dome consisting of eclogite-bearing continental-oceanic units (ICM and Zermatt-Saas Zones) beneath greenschist ones (Combin Zone).

78 FR 77106 - U.S. Air Force Reminder Re: United Launch Alliance (ULA) Consent Order and Recent Change in...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-20

...: Headquarters Air Force, Deputy Under Secretary of the Air Force (Space). ACTION: Publicize Consent Order... Force (Space), as the Compliance Officer under the Federal Trade Commission (FTC) Decision and Order... Under Secretary of the Air Force (Space). This position is now held by Dr. Troy Meink. [[Page 77107...

77 FR 9267 - Child Labor, Forced Labor, and Forced or Indentured Child Labor in the Production of Goods in...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-16

... DEPARTMENT OF LABOR Child Labor, Forced Labor, and Forced or Indentured Child Labor in the... Child Labor AGENCY: The Bureau of International Labor Affairs, United States Department of Labor. ACTION..., 2011, regarding child labor and forced labor in foreign countries. Relevant information will be used by...

78 FR 72714 - Child Labor, Forced Labor, and Forced or Indentured Child Labor in the Production of Goods in...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-03

... DEPARTMENT OF LABOR Child Labor, Forced Labor, and Forced or Indentured Child Labor in the... Child Labor AGENCY: The Bureau of International Labor Affairs, United States Department of Labor. ACTION..., 2013, regarding child labor and forced labor in foreign countries. Relevant information will be used by...

Deformed Shape Analysis of Coupled Glazing Systems

DTIC Science & Technology

2013-09-01

Tyndall Air Force Base, Florida, USA ABSTRACT Glazing in storefront and curtain wall configurations is increasingly used in areas subjected to... AIR FORCE CIVIL ENGINEER CENTER READINESS DIRECTORATE  Requirements & Acquisition Division  United States Air Force  Tyndall Air Force...Antonio, Texas; %Omaha, Nebraska #Jacobs Technology, Fort Walton Beach, Florida Air Force Civil Engineer Center Readiness Directorate Requirements

Characterization of the mechanomyographic signal of three different muscles and at different levels of isometric contractions.

PubMed

Jotta, Bruno; Cavalcanti Garcia, Marco Antonio; Visintainer Pino, Alexandre; De Souza, Marcio Nogueira

2015-01-01

Lateral (X) and longitudinal (Y) mechanical oscillations of muscle fibers that take place during muscular contraction seem to contain information additionally to the myoelectric activity, which can contribute to the interpretation of some muscle gradation force mechanisms. However, no previous study was found that had investigated the relationship between the muscle force and features associated to the mechanomyographic (MMG) signal obtained by means of a biaxial accelerometer in three different muscles. Therefore, the aim of this study was to evaluate the relationship between the force output at different load levels (20% to 100%) of the maximum voluntary isometric contraction (%MVIC) and the two signals supplied by a biaxial accelerometer and, in addition, the so-called resultant (R) acceleration signal derived from the two signals mentioned previously. Twenty seven male volunteers participated in this study. The force output related to the right biceps brachii, soleus and gastrocnemius medialis muscles was studied by means of linear regression models fit to log-transformed of the root mean square (RMS) values of the MMG signals in X, Y, and R axes versus each %MVIC. The phase angle of R acceleration (PhaseR) and anthropometric data were also considered. The angular coefficient a and the antilog of y-intercept b from the log-transformed of MMG data values versus force output were able to distinguish partially motor unit strategies during isometric contractions in the three muscles studied. The findings suggest that biaxial accelerometer seems to be an interesting approach in the assessment of muscle contraction properties.

Thermosyphon Flooding Limits in Reduced Gravity Environments

NASA Technical Reports Server (NTRS)

Gibson, Marc A.; Jaworske, Donald A.; Sanzi, James L.; Ljubanovic, Damir

2012-01-01

Fission Power Systems have long been recognized as potential multi-kilowatt power solutions for lunar, Martian, and extended planetary surface missions. Current heat rejection technology associated with fission surface power systems has focused on titanium water thermosyphons embedded in carbon composite radiator panels. The thermosyphons, or wickless heat pipes, are used as a redundant and efficient way to spread the waste heat from the power conversion unit(s) over the radiator surface area where it can be rejected to space. It is well known that thermosyphon performance is reliant on gravitational forces to keep the evaporator wetted with the working fluid. One of the performance limits that can be encountered, if not understood, is the phenomenon of condenser flooding, otherwise known as evaporator dry out. This occurs when the gravity forces acting on the condensed fluid cannot overcome the shear forces created by the vapor escaping the evaporator throat. When this occurs, the heat transfer process is stalled and may not re-stabilize to effective levels without corrective control actions. The flooding limit in earth's gravity environment is well understood as experimentation is readily accessible, but when the environment and gravity change relative to other planetary bodies, experimentation becomes difficult. An innovative experiment was designed and flown on a parabolic flight campaign to achieve the Reduced Gravity Environments (RGE) needed to obtain empirical data for analysis. The test data is compared to current correlation models for validation and accuracy.

Portuguese version of the EUROPEP questionnaire: contributions to the psychometric validation

PubMed Central

Roque, Hugo; Veloso, Ana; Ferreira, Pedro L

2016-01-01

ABSTRACT OBJECTIVE To assess the construct validity and reliability of the Portuguese version of the European Task Force on Patient Evaluation of General Practice Care questionnaire. METHODS We applied the Portuguese version of the European Task Force on Patient Evaluation of General Practice Care to 392 users of 20 Family Health Units from the North of Portugal. The validity of the construct was evaluated by exploratory factor analysis, with the Principal Axis Factoring method, by orthogonal rotation (varimax procedure), by the Kaiser normalization criteria (eigenvalue ≥ 1). The factorability of the data matrix was verified by the Kaiser-Meyer-Olkin and Bartlett’s sphericity test. We estimated the reliability by the indicator of internal consistency Cronbach’s alpha. To analyze the correlations between satisfaction and loyalty, we used the Pearson correlations. The predictor effect of satisfaction on loyalty was analyzed by simple linear regression. RESULTS Satisfaction presented five robust and well individualized dimensions – medical care, nursing care, clinical secretariat services, accessibility, and organization of services – with alpha values between 0.86 and 0.97, good levels of internal consistency. The loyalty showed alpha value of 0.72, considered a reasonable internal consistency. The satisfaction was predictive of loyalty. CONCLUSIONS The Portuguese European Task Force on Patient Evaluation of General Practice Care questionnaire is a robust and reliable instrument to measure the satisfaction and loyalty of users of the Family Health Units. PMID:27706374

Strength training, but not endurance training, reduces motor unit discharge rate variability.

PubMed

Vila-Chã, Carolina; Falla, Deborah

2016-02-01

This study evaluates and compares the effects of strength and endurance training on motor unit discharge rate variability and force steadiness of knee extensor muscles. Thirty sedentary healthy men (age, 26.0±3.8yrs) were randomly assigned to strength training, endurance training or a control group. Conventional endurance and strength training was performed 3days per week, over a period of 6weeks. Maximum voluntary contraction (MVC), time to task failure (at 30% MVC), coefficient of variation (CoV) of force and of the discharges rates of motor units from the vastus medialis obliquus and vastus lateralis were determined as subjects performed 20% and 30% MVC knee extension contractions before and after training. CoV of motor unit discharges rates was significantly reduced for both muscles following strength training (P<0.001), but did not change in the endurance (P=0.875) or control group (P=0.995). CoV of force was reduced after the strength training intervention only (P<0.01). Strength training, but not endurance training, reduces motor unit discharge rate variability and enhances force steadiness of the knee extensors. These results provide new insights into the neuromuscular adaptations that occur with different training methods. Copyright © 2015 Elsevier Ltd. All rights reserved.

On the dynamic response at the wheel axle of a pneumatic tire

NASA Astrophysics Data System (ADS)

Kung, L. E.; Soedel, W.; Yang, T. Y.

1986-06-01

A method for calculating the steady state displacement response and force transmission at the wheel axle of a pneumatic tire-suspension system due to a steady state force or displacement excitation at the tire to ground contact point is developed. The method requires the frequency responses (or receptances)_of both tire-wheel and suspension units. The frequency response of the tire-wheel unit is obtained by using the modal expansion method. The natural frequencies and mode shapes of the tire-wheel unit are obtained by using a geometrically non-linear, ring type, thin shell finite element of laminate composite. The frequency response of the suspension unit is obtained analytically. These frequency responses are used to calculate the force-input and the displacement-input responses at the wheel axle. This method allows the freedom of designing a vehicle and its tires independently and still achieving optimum dynamic performance.

Shifts in the relationship between motor unit recruitment thresholds versus derecruitment thresholds during fatigue.

PubMed

Stock, Matt S; Mota, Jacob A

2017-12-01

Muscle fatigue is associated with diminished twitch force amplitude. We examined changes in the motor unit recruitment versus derecruitment threshold relationship during fatigue. Nine men (mean age = 26 years) performed repeated isometric contractions at 50% maximal voluntary contraction (MVC) knee extensor force until exhaustion. Surface electromyographic signals were detected from the vastus lateralis, and were decomposed into their constituent motor unit action potential trains. Motor unit recruitment and derecruitment thresholds and firing rates at recruitment and derecruitment were evaluated at the beginning, middle, and end of the protocol. On average, 15 motor units were studied per contraction. For the initial contraction, three subjects showed greater recruitment thresholds than derecruitment thresholds for all motor units. Five subjects showed greater recruitment thresholds than derecruitment thresholds for only low-threshold motor units at the beginning, with a mean cross-over of 31.6% MVC. As the muscle fatigued, many motor units were derecruited at progressively higher forces. In turn, decreased slopes and increased y-intercepts were observed. These shifts were complemented by increased firing rates at derecruitment relative to recruitment. As the vastus lateralis fatigued, the central nervous system's compensatory adjustments resulted in a shift of the regression line of the recruitment versus derecruitment threshold relationship. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.

Impact of Scheduled Attrition Rates on Meeting Monthly Sortie Goals in United States Air Force Bomb Wings

DTIC Science & Technology

2009-06-12

predict future losses in the monthly flying schedules. The purpose of the attrition is to ensure that units meet their sortie contract consistently. In...an era of decreasing force size, it is important for units to maximize aircrew training operations, without wasting manpower and resources. Thus, the ...primary research question is as follows: Is the current USAF scheduling technique of using a 5-year historical attrition rate an effective way to