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Sample records for stride length measurement

  1. Stride length: measuring its instantaneous value

    International Nuclear Information System (INIS)

    Campiglio, G C; Mazzeo, J R

    2007-01-01

    Human gait has been studied from different viewpoints: kinematics, dynamics, sensibility and others. Many of its characteristics still remain open to research, both for normal gait and for pathological gait. Objective measures of some of its most significant spatial/temporal parameters are important in this context. Stride length, one of these parameters, is defined as the distance between two consecutive contacts of one foot with ground. On this work we present a device designed to provide automatic measures of stride length. Its features make it particularly appropriate for the evaluation of pathological gait

  2. Mobile Stride Length Estimation With Deep Convolutional Neural Networks.

    Science.gov (United States)

    Hannink, Julius; Kautz, Thomas; Pasluosta, Cristian F; Barth, Jens; Schulein, Samuel; GaBmann, Karl-Gunter; Klucken, Jochen; Eskofier, Bjoern M

    2018-03-01

    Accurate estimation of spatial gait characteristics is critical to assess motor impairments resulting from neurological or musculoskeletal disease. Currently, however, methodological constraints limit clinical applicability of state-of-the-art double integration approaches to gait patterns with a clear zero-velocity phase. We describe a novel approach to stride length estimation that uses deep convolutional neural networks to map stride-specific inertial sensor data to the resulting stride length. The model is trained on a publicly available and clinically relevant benchmark dataset consisting of 1220 strides from 101 geriatric patients. Evaluation is done in a tenfold cross validation and for three different stride definitions. Even though best results are achieved with strides defined from midstance to midstance with average accuracy and precision of , performance does not strongly depend on stride definition. The achieved precision outperforms state-of-the-art methods evaluated on the same benchmark dataset by . Due to the independence of stride definition, the proposed method is not subject to the methodological constrains that limit applicability of state-of-the-art double integration methods. Furthermore, it was possible to improve precision on the benchmark dataset. With more precise mobile stride length estimation, new insights to the progression of neurological disease or early indications might be gained. Due to the independence of stride definition, previously uncharted diseases in terms of mobile gait analysis can now be investigated by retraining and applying the proposed method.

  3. Select injury-related variables are affected by stride length and foot strike style during running.

    Science.gov (United States)

    Boyer, Elizabeth R; Derrick, Timothy R

    2015-09-01

    Some frontal plane and transverse plane variables have been associated with running injury, but it is not known if they differ with foot strike style or as stride length is shortened. To identify if step width, iliotibial band strain and strain rate, positive and negative free moment, pelvic drop, hip adduction, knee internal rotation, and rearfoot eversion differ between habitual rearfoot and habitual mid-/forefoot strikers when running with both a rearfoot strike (RFS) and a mid-/forefoot strike (FFS) at 3 stride lengths. Controlled laboratory study. A total of 42 healthy runners (21 habitual rearfoot, 21 habitual mid-/forefoot) ran overground at 3.35 m/s with both a RFS and a FFS at their preferred stride lengths and 5% and 10% shorter. Variables did not differ between habitual groups. Step width was 1.5 cm narrower for FFS, widening to 0.8 cm as stride length shortened. Iliotibial band strain and strain rate did not differ between foot strikes but decreased as stride length shortened (0.3% and 1.8%/s, respectively). Pelvic drop was reduced 0.7° for FFS compared with RFS, and both pelvic drop and hip adduction decreased as stride length shortened (0.8° and 1.5°, respectively). Peak knee internal rotation was not affected by foot strike or stride length. Peak rearfoot eversion was not different between foot strikes but decreased 0.6° as stride length shortened. Peak positive free moment (normalized to body weight [BW] and height [h]) was not affected by foot strike or stride length. Peak negative free moment was -0.0038 BW·m/h greater for FFS and decreased -0.0004 BW·m/h as stride length shortened. The small decreases in most variables as stride length shortened were likely associated with the concomitant wider step width. RFS had slightly greater pelvic drop, while FFS had slightly narrower step width and greater negative free moment. Shortening one's stride length may decrease or at least not increase propensity for running injuries based on the variables

  4. Stride length: the impact on propulsion and bracing ground reaction force in overhand throwing.

    Science.gov (United States)

    Ramsey, Dan K; Crotin, Ryan L

    2018-03-26

    Propulsion and bracing ground reaction force (GRF) in overhand throwing are integral in propagating joint reaction kinetics and ball velocity, yet how stride length effects drive (hind) and stride (lead) leg GRF profiles remain unknown. Using a randomised crossover design, 19 pitchers (15 collegiate and 4 high school) were assigned to throw 2 simulated 80-pitch games at ±25% of their desired stride length. An integrated motion capture system with two force plates and radar gun tracked each throw. Vertical and anterior-posterior GRF was normalised then impulse was derived. Paired t-tests identified whether differences between conditions were significant. Late in single leg support, peak propulsion GRF was statistically greater for the drive leg with increased stride. Stride leg peak vertical GRF in braking occurred before acceleration with longer strides, but near ball release with shorter strides. Greater posterior shear GRF involving both legs demonstrated increased braking with longer strides. Conversely, decreased drive leg propulsion reduced both legs' braking effects with shorter strides. Results suggest an interconnection between normalised stride length and GRF application in propulsion and bracing. This work has shown stride length to be an important kinematic factor affecting the magnitude and timing of external forces acting upon the body.

  5. Effects of footwear and stride length on metatarsal strains and failure in running.

    Science.gov (United States)

    Firminger, Colin R; Fung, Anita; Loundagin, Lindsay L; Edwards, W Brent

    2017-11-01

    The metatarsal bones of the foot are particularly susceptible to stress fracture owing to the high strains they experience during the stance phase of running. Shoe cushioning and stride length reduction represent two potential interventions to decrease metatarsal strain and thus stress fracture risk. Fourteen male recreational runners ran overground at a 5-km pace while motion capture and plantar pressure data were collected during four experimental conditions: traditional shoe at preferred and 90% preferred stride length, and minimalist shoe at preferred and 90% preferred stride length. Combined musculoskeletal - finite element modeling based on motion analysis and computed tomography data were used to quantify metatarsal strains and the probability of failure was determined using stress-life predictions. No significant interactions between footwear and stride length were observed. Running in minimalist shoes increased strains for all metatarsals by 28.7% (SD 6.4%; pRunning at 90% preferred stride length decreased strains for metatarsal 4 by 4.2% (SD 2.0%; p≤0.007), and no differences in probability of failure were observed. Significant increases in metatarsal strains and the probability of failure were observed for recreational runners acutely transitioning to minimalist shoes. Running with a 10% reduction in stride length did not appear to be a beneficial technique for reducing the risk of metatarsal stress fracture, however the increased number of loading cycles for a given distance was not detrimental either. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. INS/EKF-based stride length, height and direction intent detection for walking assistance robots.

    Science.gov (United States)

    Brescianini, Dario; Jung, Jun-Young; Jang, In-Hun; Park, Hyun Sub; Riener, Robert

    2011-01-01

    We propose an algorithm used to obtain the information on stride length, height difference, and direction based on user's intent during walking. For exoskeleton robots used to assist paraplegic patients' walking, this information is used to generate gait patterns by themselves in on-line. To obtain this information, we attach an inertial measurement unit(IMU) on crutches and apply an extended kalman filter-based error correction method to reduce the phenomena of drift due to bias of the IMU. The proposed method is verifed in real walking scenarios including walking, climbing up-stairs, and changing direction of walking with normal. © 2011 IEEE

  7. Effects of different frequencies of rhythmic auditory cueing on the stride length, cadence, and gait speed in healthy young females.

    Science.gov (United States)

    Yu, Lili; Zhang, Qi; Hu, Chunying; Huang, Qiuchen; Ye, Miao; Li, Desheng

    2015-02-01

    [Purpose] The aim of this study was to explore the effects of different frequencies of rhythmic auditory cueing (RAC) on stride length, cadence, and gait speed in healthy young females. The findings of this study might be used as clinical guidance of physical therapy for choosing the suitable frequency of RAC. [Subjects] Thirteen healthy young females were recruited in this study. [Methods] Ten meters walking tests were measured in all subjects under 4 conditions with each repeated 3 times and a 3-min seated rest period between repetitions. Subjects first walked as usual and then were asked to listen carefully to the rhythm of a metronome and walk with 3 kinds of RAC (90%, 100%, and 110% of the mean cadence). The three frequencies (90%, 100%, and 110%) of RAC were randomly assigned. Gait speed, stride length, and cadence were calculated, and a statistical analysis was performed using the SPSS (version 17.0) computer package. [Results] The gait speed and cadence of 90% RAC walking showed significant decreases compared with normal walking and 100% and 110% RAC walking. The stride length, cadence, and gait speed of 110% RAC walking showed significant increases compared with normal walking and 90% and 100% RAC walking. [Conclusion] Our results showed that 110% RAC was the best of the 3 cueing frequencies for improvement of stride length, cadence, and gait speed in healthy young females.

  8. Knee Angle and Stride Length in Association with Ball Speed in Youth Baseball Pitchers

    Directory of Open Access Journals (Sweden)

    Bart van Trigt

    2018-05-01

    Full Text Available The purpose of this study was to determine whether stride length and knee angle of the leading leg at foot contact, at the instant of maximal external rotation of the shoulder, and at ball release are associated with ball speed in elite youth baseball pitchers. In this study, fifty-two elite youth baseball pitchers (mean age 15.2 SD (standard deviation 1.7 years pitched ten fastballs. Data were collected with three high-speed video cameras at a frequency of 240 Hz. Stride length and knee angle of the leading leg were calculated at foot contact, maximal external rotation, and ball release. The associations between these kinematic variables and ball speed were separately determined using generalized estimating equations. Stride length as percentage of body height and knee angle at foot contact were not significantly associated with ball speed. However, knee angles at maximal external rotation and ball release were significantly associated with ball speed. Ball speed increased by 0.45 m/s (1 mph with an increase in knee extension of 18 degrees at maximal external rotation and 19.5 degrees at ball release. In conclusion, more knee extension of the leading leg at maximal external rotation and ball release is associated with higher ball speeds in elite youth baseball pitchers.

  9. A single hydrotherapy session increases range of motion and stride length in Labrador retrievers diagnosed with elbow dysplasia.

    Science.gov (United States)

    Preston, T; Wills, A P

    2018-04-01

    Canine elbow dysplasia is a debilitating condition of unknown aetiology and is a common cause of forelimb lameness in dogs. Canine hydrotherapy is a therapeutic approach rapidly increasing in popularity for the treatment of a range of musculoskeletal pathologies. In this study, kinematic analysis was used to assess the effect of a customised hydrotherapy session on the range of motion, stride length and stride frequency of healthy Labrador retrievers (n=6) and Labrador retrievers diagnosed with bilateral elbow dysplasia (n=6). Reflective kinematic markers were attached to bony anatomical landmarks and dogs were recorded walking at their preferred speed on a treadmill before and 10min after a single hydrotherapy session. Range of motion, stride length and stride frequency were calculated for both forelimbs. Data were analysed via a robust mixed ANOVA to assess the effect of hydrotherapy on the kinematic parameters of both groups. Range of motion was greater in the healthy dogs at baseline (PHydrotherapy increased the range of motion of the forelimbs of both groups (PHydrotherapy stride length (Phydrotherapy only in the left limb (Phydrotherapy as a therapeutic tool for the rehabilitation and treatment of Labradors with elbow dysplasia. Furthermore, results indicate that hydrotherapy might improve the gait and movement of healthy dogs. However, whether these results are transient or sustained remains undetermined. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. Manipulating the stride length/stride velocity relationship of walking using a treadmill and rhythmic auditory cueing in non-disabled older individuals. A short-term feasibility study.

    Science.gov (United States)

    Eikema, D J A; Forrester, L W; Whitall, J

    2014-09-01

    One target for rehabilitating locomotor disorders in older adults is to increase mobility by improving walking velocity. Combining rhythmic auditory cueing (RAC) and treadmill training permits the study of the stride length/stride velocity ratio (SL/SV), often reduced in those with mobility deficits. We investigated the use of RAC to increase velocity by manipulating the SL/SV ratio in older adults. Nine participants (6 female; age: 61.1 ± 8.8 years) walked overground on a gait mat at preferred and fast speeds. After acclimatization to comfortable speed on a treadmill, participants adjusted their cadence to match the cue for 3 min at 115% of preferred speed by either (a) increasing stride length only or (b) increasing stride frequency only. Following training, participants walked across the gait mat at preferred velocity without, and then with, RAC. Group analysis determined no immediate overground velocity increase, but reintroducing RAC did produce an increase in velocity after both conditions. Group and single subject analysis determined that the SL/SV ratio changed in the intended direction only in the stride length condition. We conclude that RAC is a powerful organizer of gait parameters, evidenced by its induced after-effects following short duration training. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Walking training with cueing of cadence improves walking speed and stride length after stroke more than walking training alone: a systematic review.

    Science.gov (United States)

    Nascimento, Lucas R; de Oliveira, Camila Quel; Ada, Louise; Michaelsen, Stella M; Teixeira-Salmela, Luci F

    2015-01-01

    After stroke, is walking training with cueing of cadence superior to walking training alone in improving walking speed, stride length, cadence and symmetry? Systematic review with meta-analysis of randomised or controlled trials. Adults who have had a stroke. Walking training with cueing of cadence. Four walking outcomes were of interest: walking speed, stride length, cadence and symmetry. This review included seven trials involving 211 participants. Because one trial caused substantial statistical heterogeneity, meta-analyses were conducted with and without this trial. Walking training with cueing of cadence improved walking speed by 0.23 m/s (95% CI 0.18 to 0.27, I(2)=0%), stride length by 0.21 m (95% CI 0.14 to 0.28, I(2)=18%), cadence by 19 steps/minute (95% CI 14 to 23, I(2)=40%), and symmetry by 15% (95% CI 3 to 26, random effects) more than walking training alone. This review provides evidence that walking training with cueing of cadence improves walking speed and stride length more than walking training alone. It may also produce benefits in terms of cadence and symmetry of walking. The evidence appears strong enough to recommend the addition of 30 minutes of cueing of cadence to walking training, four times a week for 4 weeks, in order to improve walking in moderately disabled individuals with stroke. PROSPERO (CRD42013005873). Copyright © 2014 Australian Physiotherapy Association. Published by Elsevier B.V. All rights reserved.

  12. Lower extremity joint loads in habitual rearfoot and mid/forefoot strike runners with normal and shortened stride lengths.

    Science.gov (United States)

    Boyer, Elizabeth R; Derrick, Timothy R

    2018-03-01

    Our purpose was to compare joint loads between habitual rearfoot (hRF) and habitual mid/forefoot strikers (hFF), rearfoot (RFS) and mid/forefoot strike (FFS) patterns, and shorter stride lengths (SLs). Thirty-eight hRF and hFF ran at their normal SL, 5% and 10% shorter, as well as with the opposite foot strike. Three-dimensional ankle, knee, patellofemoral (PF) and hip contact forces were calculated. Nearly all contact forces decreased with a shorter SL (1.2-14.9% relative to preferred SL). In general, hRF had higher PF (hRF-RFS: 10.8 ± 1.4, hFF-FFS: 9.9 ± 2.0 BWs) and hip loads (axial hRF-RFS: -9.9 ± 0.9, hFF-FFS: -9.6 ± 1.0 BWs) than hFF. Many loads were similar between foot strike styles for the two groups, including axial and lateral hip, PF, posterior knee and shear ankle contact forces. Lateral knee and posterior hip contact forces were greater for RFS, and axial ankle and knee contact forces were greater for FFS. The tibia may be under greater loading with a FFS because of these greater axial forces. Summarising, a particular foot strike style does not universally decrease joint contact forces. However, shortening one's SL 10% decreased nearly all lower extremity contact forces, so it may hold potential to decrease overuse injuries associated with excessive joint loads.

  13. Overview of bunch length measurements

    International Nuclear Information System (INIS)

    Lumpkin, A. H.

    1999-01-01

    An overview of particle and photon beam bunch length measurements is presented in the context of free-electron laser (FEL) challenges. Particle-beam peak current is a critical factor in obtaining adequate FEL gain for both oscillators and self-amplified spontaneous emission (SASE) devices. Since measurement of charge is a standard measurement, the bunch length becomes the key issue for ultrashort bunches. Both time-domain and frequency-domain techniques are presented in the context of using electromagnetic radiation over eight orders of magnitude in wavelength. In addition, the measurement of microbunching in a micropulse is addressed

  14. CEBAF Upgrade Bunch Length Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Mahmoud [Old Dominion Univ., Norfolk, VA (United States)

    2016-05-01

    Many accelerators use short electron bunches and measuring the bunch length is important for efficient operations. CEBAF needs a suitable bunch length because bunches that are too long will result in beam interruption to the halls due to excessive energy spread and beam loss. In this work, bunch length is measured by invasive and non-invasive techniques at different beam energies. Two new measurement techniques have been commissioned; a harmonic cavity showed good results compared to expectations from simulation, and a real time interferometer is commissioned and first checkouts were performed. Three other techniques were used for measurements and comparison purposes without modifying the old procedures. Two of them can be used when the beam is not compressed longitudinally while the other one, the synchrotron light monitor, can be used with compressed or uncompressed beam.

  15. Minimal Length, Measurability and Gravity

    Directory of Open Access Journals (Sweden)

    Alexander Shalyt-Margolin

    2016-03-01

    Full Text Available The present work is a continuation of the previous papers written by the author on the subject. In terms of the measurability (or measurable quantities notion introduced in a minimal length theory, first the consideration is given to a quantum theory in the momentum representation. The same terms are used to consider the Markov gravity model that here illustrates the general approach to studies of gravity in terms of measurable quantities.

  16. A Comparative Analysis of Selected Mechanical Aspects of the Ice Skating Stride.

    Science.gov (United States)

    Marino, G. Wayne

    This study quantitatively analyzes selected aspects of the skating strides of above-average and below-average ability skaters. Subproblems were to determine how stride length and stride rate are affected by changes in skating velocity, to ascertain whether the basic assumption that stride length accurately approximates horizontal movement of the…

  17. Interaction effects of stride angle and strike pattern on running economy.

    Science.gov (United States)

    Santos-Concejero, J; Tam, N; Granados, C; Irazusta, J; Bidaurrazaga-Letona, I; Zabala-Lili, J; Gil, S M

    2014-12-01

    This study aimed to investigate the relationship between stride angle and running economy (RE) in athletes with different foot strike patterns. 30 male runners completed 4 min running stages on a treadmill at different velocities. During the test, biomechanical variables such as stride angle, swing time, contact time, stride length and frequency were recorded using an optical measurement system. Their foot strike pattern was determined, and VO2 at velocities below the lactate threshold were measured to calculate RE. Midfoot/forefoot strikers had better RE than rearfoot strikers (201.5±5.6 ml · kg(-1) · km(-1) vs. 213.5±4.2 ml · kg(-1) · km(-1)respectively; p=0.019). Additionally, midfoot/fore-foot strikers presented higher stride angles than rearfoot strikers (p=0.043). Linear modelling analysis showed that stride angle is closely related to RE (r=0.62, pstrike pattern is likely to be more economical, whereas at any lower degree, the midfoot/forefoot strike pattern appears to be more desirable. A biomechanical running technique characterised by high stride angles and a midfoot/forefoot strike pattern is advantageous for a better RE. Athletes may find stride angle useful for improving RE. © Georg Thieme Verlag KG Stuttgart · New York.

  18. Measuring Crack Length in Coarse Grain Ceramics

    Science.gov (United States)

    Salem, Jonathan A.; Ghosn, Louis J.

    2010-01-01

    Due to a coarse grain structure, crack lengths in precracked spinel specimens could not be measured optically, so the crack lengths and fracture toughness were estimated by strain gage measurements. An expression was developed via finite element analysis to correlate the measured strain with crack length in four-point flexure. The fracture toughness estimated by the strain gaged samples and another standardized method were in agreement.

  19. Maximum swimming speeds of sailfish and three other large marine predatory fish species based on muscle contraction time and stride length: a myth revisited

    Directory of Open Access Journals (Sweden)

    Morten B. S. Svendsen

    2016-10-01

    Full Text Available Billfishes are considered to be among the fastest swimmers in the oceans. Previous studies have estimated maximum speed of sailfish and black marlin at around 35 m s−1 but theoretical work on cavitation predicts that such extreme speed is unlikely. Here we investigated maximum speed of sailfish, and three other large marine pelagic predatory fish species, by measuring the twitch contraction time of anaerobic swimming muscle. The highest estimated maximum swimming speeds were found in sailfish (8.3±1.4 m s−1, followed by barracuda (6.2±1.0 m s−1, little tunny (5.6±0.2 m s−1 and dorado (4.0±0.9 m s−1; although size-corrected performance was highest in little tunny and lowest in sailfish. Contrary to previously reported estimates, our results suggest that sailfish are incapable of exceeding swimming speeds of 10-15 m s−1, which corresponds to the speed at which cavitation is predicted to occur, with destructive consequences for fin tissues.

  20. Bunch Length Measurements in SPEAR3

    Energy Technology Data Exchange (ETDEWEB)

    Corbett, W.J.; Fisher, A.; Huang, X.; Safranek, J.; Sebek, J.; /SLAC; Lumpkin, A.; /Argonne; Sannibale, F.; /LBL, Berkeley; Mok, W.; /Unlisted

    2007-11-28

    A series of bunch length measurements were made in SPEAR3 for two different machine optics. In the achromatic optics the bunch length increases from the low-current value of 16.6ps rms to about 30ps at 25ma/bunch yielding an inductive impedance of -0.17{Omega}. Reducing the momentum compaction factor by a factor of {approx}60 [1] yields a low-current bunch length of {approx}4ps rms. In this paper we review the experimental setup and results.

  1. Stride rate and walking intensity in healthy older adults.

    Science.gov (United States)

    Peacock, Leslie; Hewitt, Allan; Rowe, David A; Sutherland, Rona

    2014-04-01

    The study investigated (a) walking intensity (stride rate and energy expenditure) under three speed instructions; (b) associations between stride rate, age, height, and walking intensity; and (c) synchronization between stride rate and music tempo during overground walking in a population of healthy older adults. Twenty-nine participants completed 3 treadmill-walking trials and 3 overground-walking trials at 3 self-selected speeds. Treadmill VO2 was measured using indirect calorimetry. Stride rate and music tempo were recorded during overground-walking trials. Mean stride rate exceeded minimum thresholds for moderate to vigorous physical activity (MVPA) under slow (111.41 ± 11.93), medium (118.17 ± 11.43), and fast (123.79 ± 11.61) instructions. A multilevel model showed that stride rate, age, and height have a significant effect (p Music can be a useful way to guide walking cadence.

  2. The effect of rider weight and additional weight in Icelandic horses in tölt: part II. Stride parameters responses.

    Science.gov (United States)

    Gunnarsson, V; Stefánsdóttir, G J; Jansson, A; Roepstorff, L

    2017-09-01

    This study investigated the effects of rider weight in the BW ratio (BWR) range common for Icelandic horses (20% to 35%), on stride parameters in tölt in Icelandic horses. The kinematics of eight experienced Icelandic school horses were measured during an incremental exercise test using a high-speed camera (300 frames/s). Each horse performed five phases (642 m each) in tölt at a BWR between rider (including saddle) and horse starting at 20% (BWR20) and increasing to 25% (BWR25), 30% (BWR30), 35% (BWR35) and finally 20% (BWR20b) was repeated. One professional rider rode all horses and weight (lead) was added to saddle and rider as needed. For each phase, eight strides at speed of 5.5 m/s were analyzed for stride duration, stride frequency, stride length, duty factor (DF), lateral advanced placement, lateral advanced liftoff, unipedal support (UPS), bipedal support (BPS) and height of front leg action. Stride length became shorter (Y=2.73-0.004x; P0.05). In conclusion, increased BWR decreased stride length and increased DF proportionally to the same extent in all limbs, whereas BPS increased at the expense of decreased UPS. These changes can be expected to decrease tölt quality when subjectively evaluated according to the breeding goals for the Icelandic horse. However, beat, symmetry and height of front leg lifting were not affected by BWR.

  3. Distance and Cable Length Measurement System

    Science.gov (United States)

    Hernández, Sergio Elias; Acosta, Leopoldo; Toledo, Jonay

    2009-01-01

    A simple, economic and successful design for distance and cable length detection is presented. The measurement system is based on the continuous repetition of a pulse that endlessly travels along the distance to be detected. There is a pulse repeater at both ends of the distance or cable to be measured. The endless repetition of the pulse generates a frequency that varies almost inversely with the distance to be measured. The resolution and distance or cable length range could be adjusted by varying the repetition time delay introduced at both ends and the measurement time. With this design a distance can be measured with centimeter resolution using electronic system with microsecond resolution, simplifying classical time of flight designs which require electronics with picosecond resolution. This design was also applied to position measurement. PMID:22303169

  4. Spectral interferometric length measurement and tomography

    International Nuclear Information System (INIS)

    Pinkl, W.

    1998-01-01

    This work presents a new method for optical length measurement using the principles of spectral interferometry. Results of thickness measurements on glass plates, the human cornea in vivo and human finger and toe nails in vivo and in vitro are discussed. It could be demonstrated that the absorption coefficient of red and green ink can be measured depth sensitive. Another chapter describes a new technique to measure a thickness profile of a sample within the illuminating beam. It could be demonstrated that a thickness profile over a distance of a few millimeters can be measured with one single measurement. At the Institute of Medical Physics of the University of Vienna a method to measure intraocular distances by the means of interferometry has been developed during the last ten years. Basing on this method (dual beam interferometry) an optical in vivo tomography experiment could be established. A thickness map of the retina of a human eye in vivo can be easily measured. The dual beam technique uses a Michelson interferometer with a moving mirror to adjust the length of the interferometer arms. The mirror is moved by a stepper motor. This movement induces vibrations, misalignment and other disadvantages. So mechanically moved parts as reasons for possible errors should be eliminated. This work shows one possible solution - using the principle of spectral interferometry. A spectral interferometry experiment is a static experiment, no moving parts are used. A spectral interferometry experiment has been used to measure the thickness of glass plates and stacks of glass plates. Using two light sources of different wavelengths spectral absorption properties of a sample can be measured depth sensitive. This could be demonstrated with stacks of glass plates and the use of red and green ink between two plates. The obtained results are compared to the results of a computer simulation. To demonstrate the ability of spectral interferometry to measure the thickness of biologic

  5. Bunch Length Measurements using Coherent Radiation

    CERN Document Server

    Ischebeck, Rasmus; Barnes, Christopher; Blumenfeld, Ian; Clayton, Chris; Decker, Franz Josef; Deng, Suzhi; Hogan, Mark; Huang Cheng Kun; Iverson, Richard; Johnson, Devon K; Krejcik, Patrick; Lu, Wei; Marsh, Kenneth; Oz, Erdem; Siemann, Robert; Walz, Dieter

    2005-01-01

    The accelerating field that can be obtained in a beam-driven plasma wakefield accelerator depends on the current of the electron beam that excites the wake. In the E-167 experiment, a peak current above 10kA will be delivered at a particle energy of 28GeV. The bunch has a length of a few ten micrometers and several methods are used to measure its longitudinal profile. Among these, autocorrelation of coherent transition radiation (CTR) is employed. The beam passes a thin metallic foil, where it emits transition radiation. For wavelengths greater than the bunch length, this transition radiation is emitted coherently. This amplifies the long-wavelength part of the spectrum. A scanning Michelson interferometer is used to autocorrelate the CTR. However, this method requires the contribution of many bunches to build an autocorrelation trace. The measurement is influenced by the transmission characteristics of the vacuum window and beam splitter. We present here an analysis of materials, as well as possible layouts ...

  6. Bunch length and impedance measurements in SPEAR

    International Nuclear Information System (INIS)

    Bane, K.; Donald, M.; Hofmann, A.; Jowett, J.; Lockman, W.; Morton, P.; Stege, R.; Spence, W.; Wilson, P.

    1988-05-01

    Subsequent to an extensive smoothing of the vacuum chamber a comprehensive study of the SPEAR impedance was undertaken. Bunch length, synchrotron quadrupole mode frequency, and parasitic mode loss were measured as functions of beam current. The results showed that, although the gross longitudinal impedance had indeed been reduced, the 'capacitive' component had also decreased relative to the 'inductive'--to the extent that previously compensated potential well distortion now induced bunch lengthening at low currents, and the turbulent threshold had actually been lowered. A specially designed multi-cell disc-loaded 'capacitor' cavity was shown to be capable of removing this effect by restoring the original compensation. A model of the new SPEAR impedance is also obtained. 7 refs., 6 figs

  7. Bunch length and impedance measurements in SPEAR

    International Nuclear Information System (INIS)

    Bane, K.; Donald, M.; Morton, P.; Stege, R.; Spence, W.; Wilson, P.; Hofmann, A.; Jowett, J.; Lockman, W.

    1988-01-01

    Subsequent to an extensive smoothing of the vacuum chamber a comprehensive study of the SPEAR impedance was undertaken. Bunch length, synchrotron quadrupole mode frequency, and parasitic mode loss were measured as functions of beam current. This paper shows that although the gross longitudinal impedance had indeed been reduced, the capacitive component had also decreased relative to the inductive - to the extent that previously compensated potential well distortion now induced bunch lengthening at low currents, and the turbulent threshold had actually been lowered. A specially designed multi-cell disc-loaded capacitor cavity was shown to be capable of removing this effect by restoring the original compensation. A model of the new SPEAR impedance is also obtained

  8. Automated path length and M56 measurements at Jefferson Lab

    International Nuclear Information System (INIS)

    Hardy, D.; Tang, J.; Legg, R.

    1997-01-01

    Accurate measurement of path length and path length changes versus momentum (M 56 ) are critical for maintaining minimum beam energy spread in the CEBAF (Continuous Electron Beam Accelerator Facility) accelerator at the Thomas Jefferson National Accelerator Facility (Jefferson Lab). The relative path length for each circuit of the beam (1256m) must be equal within 1.5 degrees of 1497 MHz RF phase. A relative path length measurement is made by measuring the relative phases of RF signals from a cavity that is separately excited for each pass of a 4.2 μs pulsed beam. This method distinguishes the path length to less than 0.5 path length error. The development of a VME based automated measurement system for path length and M 56 has contributed to faster machine setup time and has the potential for use as a feedback parameter for automated control

  9. Tropicalized Lambda Lengths, Measured Laminations and Convexity

    DEFF Research Database (Denmark)

    C. Penner, R.

    This work uncovers the tropical analogue for measured laminations of the convex hull construction of decorated Teichmueller theory, namely, it is a study in coordinates of geometric degeneration to a point of Thurston's boundary for Teichmueller space. This may offer a paradigm for the extension ...

  10. Examination of the gait pattern based on adjusting and resulting components of the stride-to-stride variability

    DEFF Research Database (Denmark)

    Laessoe, Uffe; Jensen, Niels Martin Brix; Madeleine, Pascal

    2017-01-01

    Stride-to-stride variability may be used as an indicator in the assessment of gait performance, but the evaluation of this parameter is not trivial. In the gait pattern, a deviation in one stride must be corrected within the next strides (elemental variables) to ensure a steady gait (performance .......5 to 2 strides with 0.5 stride increments. The time lag values corresponded to the following contralateral stride, the following ipsilateral stride, the second following contralateral stride and the second following ipsilateral stride....

  11. Young Children's Understandings of Length Measurement: Evaluating a Learning Trajectory

    Science.gov (United States)

    Szilagyi, Janka; Clements, Douglas H.; Sarama, Julie

    2013-01-01

    This study investigated the development of length measurement ideas in students from prekindergarten through 2nd grade. The main purpose was to evaluate and elaborate the developmental progression, or levels of thinking, of a hypothesized learning trajectory for length measurement to ensure that the sequence of levels of thinking is consistent…

  12. From Concrete to Abstract in the Measurement of Length

    International Nuclear Information System (INIS)

    Stephanou, Andreas; Fisher, William P Jr

    2013-01-01

    The concatenation of units of length is widely viewed as the paradigmatic expression of fundamental measurement. Survey, assessment, and test scores in educational and psychological measurement are often interpreted in ways that assume a concatenation of units to have been established, even though these assumptions are rarely stated or tested. A concatenation model for measurement is shown to be equivalent to a Rasch model: any two units of measurement placed end to end must together be of the same length as either one of them added to itself. This additive principle and a concatenation model of measurement together serve as a heuristic guide for organizing two experimental approaches to calibrating instruments for measuring length. The capacity to reproduce the unit of measurement from theory with no need for repeated empirical calibration experiments, as in the geometrical bisection of the line and the resultant halving of the length measure, is highlighted as essential to demonstrating a thorough understanding of the construct

  13. Analysis and Classification of Stride Patterns Associated with Children Development Using Gait Signal Dynamics Parameters and Ensemble Learning Algorithms

    Directory of Open Access Journals (Sweden)

    Meihong Wu

    2016-01-01

    Full Text Available Measuring stride variability and dynamics in children is useful for the quantitative study of gait maturation and neuromotor development in childhood and adolescence. In this paper, we computed the sample entropy (SampEn and average stride interval (ASI parameters to quantify the stride series of 50 gender-matched children participants in three age groups. We also normalized the SampEn and ASI values by leg length and body mass for each participant, respectively. Results show that the original and normalized SampEn values consistently decrease over the significance level of the Mann-Whitney U test (p<0.01 in children of 3–14 years old, which indicates the stride irregularity has been significantly ameliorated with the body growth. The original and normalized ASI values are also significantly changing when comparing between any two groups of young (aged 3–5 years, middle (aged 6–8 years, and elder (aged 10–14 years children. Such results suggest that healthy children may better modulate their gait cadence rhythm with the development of their musculoskeletal and neurological systems. In addition, the AdaBoost.M2 and Bagging algorithms were used to effectively distinguish the children’s gait patterns. These ensemble learning algorithms both provided excellent gait classification results in terms of overall accuracy (≥90%, recall (≥0.8, and precision (≥0.8077.

  14. Bunch length measurements in the SLC damping ring

    International Nuclear Information System (INIS)

    Decker, F.J.; Limberg, T.; Minty, M.; Ross, M.

    1993-05-01

    The synchrotron light of the SLC damping ring was used to measure the bunch length with a streak camera at different times in the damping cycle. There are bunch length oscillations after injection, different equilibrium length during the cycle due to rf manipulations to avoid microwave instability oscillations, and just before extraction there is a longitudinal phase space rotation (bunch muncher) to shorten the bunch length. Measurements under these different conditions are presented and compared with BPM pulse height signals. Calibration and adjustment issues and the connection of the streak camera to the SLC control system are also discussed

  15. Cervical length measurement: comparison of transabdominal and transvaginal approach

    DEFF Research Database (Denmark)

    Westerway, Sue C; Pedersen, Lars Henning; Hyett, Jon

    2015-01-01

    to external cervical os. Bland- Altman plots and Wilcoxon signed rank test were used to evaluate differences between TA and TV measurements. Results: The validity of the TA method depended on cervical length. Although the TA method underestimated cervical length by 2.0 mm on average (P ... plots showed an inverse trend with shorter cervixes. In women with a cervix test to detect cervical length

  16. Validity of plant fiber length measurement : a review of fiber length measurement based on kenaf as a model

    Science.gov (United States)

    James S. Han; Theodore. Mianowski; Yi-yu. Lin

    1999-01-01

    The efficacy of fiber length measurement techniques such as digitizing, the Kajaani procedure, and NIH Image are compared in order to determine the optimal tool. Kenaf bast fibers, aspen, and red pine fibers were collected from different anatomical parts, and the fiber lengths were compared using various analytical tools. A statistical analysis on the validity of the...

  17. In vivo myograph measurement of muscle contraction at optimal length

    Directory of Open Access Journals (Sweden)

    Ahmed Aminul

    2007-01-01

    Full Text Available Abstract Background Current devices for measuring muscle contraction in vivo have limited accuracy in establishing and re-establishing the optimum muscle length. They are variable in the reproducibility to determine the muscle contraction at this length, and often do not maintain precise conditions during the examination. Consequently, for clinical testing only semi-quantitative methods have been used. Methods We present a newly developed myograph, an accurate measuring device for muscle contraction, consisting of three elements. Firstly, an element for adjusting the axle of the device and the physiological axis of muscle contraction; secondly, an element to accurately position and reposition the extremity of the muscle; and thirdly, an element for the progressive pre-stretching and isometric locking of the target muscle. Thus it is possible to examine individual in vivo muscles in every pre-stretched, specified position, to maintain constant muscle-length conditions, and to accurately re-establish the conditions of the measurement process at later sessions. Results In a sequence of experiments the force of contraction of the muscle at differing stretching lengths were recorded and the forces determined. The optimum muscle length for maximal force of contraction was established. In a following sequence of experiments with smaller graduations around this optimal stretching length an increasingly accurate optimum muscle length for maximal force of contraction was determined. This optimum length was also accurately re-established at later sessions. Conclusion We have introduced a new technical solution for valid, reproducible in vivo force measurements on every possible point of the stretching curve. Thus it should be possible to study the muscle contraction in vivo to the same level of accuracy as is achieved in tests with in vitro organ preparations.

  18. Interobserver Variation of the Renal Length Measurement on Ultrasonography

    International Nuclear Information System (INIS)

    Jeong, Yoong Ki; Chung, Hye Weon; Kim, Tae Sung; Ryoo, Jae Wook; Kim, Tae Kyoung; Kim, Seung Hyup

    1995-01-01

    We assessed interobserver variation in the measurement of the renal length on ultrasonography. Ultrasonographic examinations were performed in randomly selected 50 patients. The maximallenhths of both kidneys were measured with calipers during the scanning from frozen images by three observers in a blinded fashion. There was a relatively constant tendency of an observer to measure a renal length either longer or shorter than the other observer(Kendall coefficient>0.05). Average interobserver variations were 0.51 cm (±0.42 cm) in right kidney and 0.53 cm (±0.41 cm) in left kidney and were within 1 cm in 91% right and 89% of left kidney. Interobserver variation about 1cm should be considered in the measurement of the renal length on ultrasonography

  19. A radiographic method for measurement of leg length inequality.

    Science.gov (United States)

    Friberg, O; Koivisto, E; Wegelius, C

    1985-01-01

    An accurate and simple radiographic method for the measurement of weight-bearing leg length inequality with a minimum of radiated body area is described. The measurement can be made in a conventional chest X-ray unit without other extra equipment than a gonad shield described here.

  20. The impact of precise robotic lesion length measurement on stent length selection: ramifications for stent savings.

    Science.gov (United States)

    Campbell, Paul T; Kruse, Kevin R; Kroll, Christopher R; Patterson, Janet Y; Esposito, Michele J

    2015-09-01

    Coronary stent deployment outcomes can be negatively impacted by inaccurate lesion measurement and inappropriate stent length selection (SLS). We compared visual estimate of these parameters to those provided by the CorPath 200® Robotic PCI System. Sixty consecutive patients who underwent coronary stent placement utilizing the CorPath System were evaluated. The treating physician assessed orthogonal images and provided visual estimates of lesion length and SLS. The robotic system was then used for the same measures. SLS was considered to be accurate when visual estimate and robotic measures were in agreement. Visual estimate SLSs were considered to be "short" or "long" if they were below or above the robotic-selected stents, respectively. Only 35% (21/60) of visually estimated lesions resulted in accurate SLS, whereas 33% (20/60) and 32% (19/60) of the visually estimated SLSs were long and short, respectively. In 5 cases (8.3%), 1 less stent was placed based on the robotic lesion measurement being shorter than the visual estimate. Visual estimate assessment of lesion length and SLS is highly variable with 65% of the cases being inaccurately measured when compared to objective measures obtained from the robotic system. The 32% of the cases where lesions were visually estimated to be short represents cases that often require the use of extra stents after the full lesion is not covered by 1 stent [longitudinal geographic miss (LGM)]. Further, these data showed that the use of the robotic system prevented the use of extra stents in 8.3% of the cases. Measurement of lesions with robotic PCI may reduce measurement errors, need for extra stents, and LGM. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Sonographic Measurement of Normal Splenic Length in Korean Adults

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Sang Bum; Cheon, Byung Kook; Kim, Jong Min; Oh, Kyung Seoung; Jung, Gyoo Sik; Huh, Jin Do; Joh, Young Duk [Kosin University College of Medicine, Busan (Korea, Republic of)

    1996-12-15

    To establish upper limit of normal splenic length of Korean adults on ultrasonography and to determice the degree of interobserver and intraobserver variation. Ultrasonographic scans were performed to measure the maximum length of spleen in 105 of 150 adults selected by convenience sampling. Remained 45 cases with any conditions that could alter splenic size were excluded from this study. The maximum length of spleen was measured and correlated with body surface area, patient height, weight, age and sex. In 31 of the 105 adults we evaluated the interobserver and intraobserver variations in sonographic measurements of splenic length obtained by three radiologists in blind fashion. The mean splenic length in 105 adults was 8.56cm ({+-} 0.95). The splenic length positively correlated with body surface area, patient height and weight (P <0.001), and negatively correlated with patient age (P < 0.01). Male spleen (8.87 cm {+-} 1.07) was longer than female spleen (8.35 cm {+-} 0.81) (P < 0.05). The following guidelines are proposed for the upper limit of normal splenic length at different groups of body surface area: no longer than 10 cm at 1.20{approx}1.59 m{sup 2}, 11 cm at1.60{approx}1.79 m{sup 2}, and 12 cm at 1.80{approx}1.99 m{sup 2}. The mean interobserver variation between any two radiologists ranged from 0.32 cm ({+-} 0.29) to 0.39 cm ({+-} 0.33) and interobserver variations were within 1 cm in 96%. The mean intraobserver variations were within 0.5 cm in 91%. The splenic length closely correlated with body surface area, patient height, weight and age. Particularly the upper limit of normal splenic length changed according to body surface area. Interobserver variation about 1 cm and intraobserver variation about 0.5 cm should be considered in the measurement of the splenic length on ultrasonography

  2. Electron bunch length measurement with a wakefield radiation decelerator

    Directory of Open Access Journals (Sweden)

    Weiwei Li

    2014-03-01

    Full Text Available In this paper, we propose a novel method to measure the electron bunch length with a dielectric wakefield radiation (DWR decelerator which is composed of two dielectric-lined waveguides (DLWs and an electron spectrometer. When an electron beam passes through a DLW, the DWR is excited which leads to an energy loss of the electron beam. The energy loss is found to be largely dependent on the electron bunch length and can be easily measured by an electron spectrometer which is essential for a normal accelerator facility. Our study shows that this method has a high resolution and a great simplicity.

  3. Measurement of Debye length in laser-produced plasma.

    Science.gov (United States)

    Ehler, W.

    1973-01-01

    The Debye length of an expanded plasma created by placing an evacuated chamber with an entrance slit in the path of a freely expanding laser produced plasma was measured, using the slab geometry. An independent measurement of electron density together with the observed value for the Debye length also provided a means for evaluating the plasma electron temperature. This temperature has applications in ascertaining plasma conductivity and magnetic field necessary for confinement of the laser produced plasma. Also, the temperature obtained would be useful in analyzing electron-ion recombination rates in the expanded plasma and the dynamics of the cooling process of the plasma expansion.

  4. Measurement of the diffusion length of thermal neutrons inside graphite

    International Nuclear Information System (INIS)

    Ertaud, A.; Beauge, R.; Fauquez, H.; De Laboulay, H.; Mercier, C.; Vautrey, L.

    1948-11-01

    The diffusion length of thermal neutrons inside a given industrial graphite is determined by measuring the neutron density inside a parallelepipedal piling up of graphite bricks (2.10 x 2.10 x 2.442 m). A 3.8 curies (Ra α → Be) source is placed inside the parallelepipedal block of graphite and thin manganese detectors are used. Corrections are added to the unweighted measurements to take into account the effects of the damping of supra-thermal neutrons in the measurement area. These corrections are experimentally deduced from the differential measurements made with a cadmium screen interposed between the source and the first plane of measurement. An error analysis completes the report. The diffusion length obtained is: L = 45.7 cm ± 0.3. The average density of the graphite used is 1.76 and the average apparent density of the piling up is 1.71. (J.S.)

  5. Measuring Clearance Mechanics Based on Dynamic Leg Length

    Science.gov (United States)

    Khamis, Sam; Danino, Barry; Hayek, Shlomo; Carmeli, Eli

    2018-01-01

    The aim of this study was to quantify clearance mechanics during gait. Seventeen children diagnosed with hemiplegic cerebral palsy underwent a three-dimensional gait analysis evaluation. Dynamic leg lengths were measured from the hip joint center to the heel, to the ankle joint center and to the forefoot throughout the gait cycle. Significant…

  6. Electro-Magnetic Bunch Length Measurement in LEP

    CERN Document Server

    Vos, L

    1998-01-01

    Bunch lengths between 3 and 12 mm have been measured routinely in LEP in 1997 with a small (7 mm diameter) button electrode. The measurement method is based on the spectral analysis of the electrode signal and relies on the fact that the transfer function of the complete set-up, including the signal cable, can be computed rather exactly thus eliminating the need for external calibration. The information of beam intensity is recovered as a by-product. It provides an interesting internal validation of the measurement by comparison with the normal intensity measurement. The system has been used to detect subtle but real bunch length changes with bunch intensity which can be attributed to the inductive impedance in LEP. A value for the imaginary (inductive) longitudinal impedance is derived from the observations. An indication for the resistive part of the impedance is given as well.

  7. Selective Breeding and Short-Term Access to a Running Wheel Alter Stride Characteristics in House Mice.

    Science.gov (United States)

    Claghorn, Gerald C; Thompson, Zoe; Kay, Jarren C; Ordonez, Genesis; Hampton, Thomas G; Garland, Theodore

    Postural and kinematic aspects of running may have evolved to support high runner (HR) mice to run approximately threefold farther than control mice. Mice from four replicate HR lines selectively bred for high levels of voluntary wheel running show many differences in locomotor behavior and morphology as compared with four nonselected control (C) lines. We hypothesized that HR mice would show stride alterations that have coadapted with locomotor behavior, morphology, and physiology. More specifically, we predicted that HR mice would have stride characteristics that differed from those of C mice in ways that parallel some of the adaptations seen in highly cursorial animals. For example, we predicted that limbs of HR mice would swing closer to the parasagittal plane, resulting in a two-dimensional measurement of narrowed stance width. We also expected that some differences between HR and C mice might be amplified by 6 d of wheel access, as is used to select breeders each generation. We used the DigiGait Imaging System (Mouse Specifics) to capture high-speed videos in ventral view as mice ran on a motorized treadmill across a range of speeds and then to automatically calculate several aspects of strides. Young adults of both sexes were tested both before and after 6 d of wheel access. Stride length, stride frequency, stance width, stance time, brake time, propel time, swing time, duty factor, and paw contact area were analyzed using a nested analysis of covariance, with body mass as a covariate. As expected, body mass and treadmill speed affected nearly every analyzed metric. Six days of wheel access also affected nearly every measure, indicating pervasive training effects, in both HR and C mice. As predicted, stance width was significantly narrower in HR than C mice. Paw contact area and duty factor were significantly greater in minimuscle individuals (subset of HR mice with 50%-reduced hind limb muscle mass) than in normal-muscled HR or C mice. We conclude that

  8. [Renal length measured by ultrasound in adult mexican population].

    Science.gov (United States)

    Oyuela-Carrasco, J; Rodríguez-Castellanos, F; Kimura, E; Delgado-Hernández, R; Herrera-Félix, J P

    2009-01-01

    Renal length estimation by ultrasound is an important parameter in clinical evaluation of kidney disease and healthy donors. Changes in renal volume may be a sign of kidney disease. Correct interpretation of renal length requires the knowledge of normal limits, these have not been described for Latin American population. To describe normal renal length (RL) by ultrasonography in a group of Mexican adults. Ultrasound measure of RL in 153 healthy Mexican adults stratified by age. Describe the association of RL to several anthropometric variables. A total of 77 males and 76 females were scanner. The average age for the group was 44.12 +/- 15.44 years. The mean weight, body mass index (BMI) and height were 68.87 +/- 11.69 Kg, 26.77 +/- 3.82 kg/m2 and 160 +/- 8.62 cm respectively. Dividing the population by gender, showed a height of 166 +/- 6.15 cm for males and 154.7 +/- 5.97 cm for females (p =0.000). Left renal length (LRL) in the whole group was 105.8 +/- 7.56 mm and right renal length (RRL) was 104.3 +/- 6.45 mm (p = 0.000.) The LRL for males was 107.16 +/- 6.97 mm and for females was 104.6 +/- 7.96 mm. The average RRL for males was 105.74 +/- 5.74 mm and for females 102.99 +/- 6.85 mm (p = 0.008.) We noted that RL decreased with age and the rate of decline accelerates alter 60 years of age. Both lengths correlated significantly and positively with weight, BMI and height. The RL was significantly larger in males than in females in both kidneys (p = 0.036) in this Mexican population. Renal length declines after 60 years of age and specially after 70 years.

  9. Electron Bunch Length Measurement for LCLS at SLAC

    International Nuclear Information System (INIS)

    Zelazny, M.; Allison, S.; Chevtsov, Sergei; Emma, P.; Kotturi, K.d.; Loos, H.; Peng, S.; Rogind, D.; Straumann, T.

    2007-01-01

    At Stanford Linear Accelerator Center (SLAC) a Bunch Length Measurement system has been developed to measure the length of the electron bunch for its new Linac Coherent Light Source (LCLS). This destructive measurement uses a transverse-mounted RF deflector (TCAV) to vertically streak the electron beam and an image taken with an insertable screen and a camera. The device control software was implemented with the Experimental Physics and Industrial Control System (EPICS) toolkit. The analysis software was implemented in Matlab(trademark) using the EPICS/Channel Access Interface for Scilab(trademark) and Matlab(trademark) (labCA). This architecture allowed engineers and physicists to develop and integrate their control and analysis without duplication of effort

  10. Investigating the correlation between paediatric stride interval persistence and gross energy expenditure

    Directory of Open Access Journals (Sweden)

    Sejdić Ervin

    2010-02-01

    Full Text Available Abstract Background Stride interval persistence, a term used to describe the correlation structure of stride interval time series, is thought to provide insight into neuromotor control, though its exact clinical meaning has not yet been realized. Since human locomotion is shaped by energy efficient movements, it has been hypothesized that stride interval dynamics and energy expenditure may be inherently tied, both having demonstrated similar sensitivities to age, disease, and pace-constrained walking. Findings This study tested for correlations between stride interval persistence and measures of energy expenditure including mass-specific gross oxygen consumption per minute (, mass-specific gross oxygen cost per meter (VO2 and heart rate (HR. Metabolic and stride interval data were collected from 30 asymptomatic children who completed one 10-minute walking trial under each of the following conditions: (i overground walking, (ii hands-free treadmill walking, and (iii handrail-supported treadmill walking. Stride interval persistence was not significantly correlated with (p > 0.32, VO2 (p > 0.18 or HR (p > 0.56. Conclusions No simple linear dependence exists between stride interval persistence and measures of gross energy expenditure in asymptomatic children when walking overground and on a treadmill.

  11. Absolute Bunch Length Measurements by Incoherent Radiation Fluctuation Analysis

    International Nuclear Information System (INIS)

    Sannibale, F.; Stupakov, G.V.; Zolotorev, M.S.; Filippetto, D.; Jagerhofer, L.

    2009-01-01

    By analyzing the pulse to pulse intensity fluctuations of the radiation emitted by a charge particle in the incoherent part of the spectrum, it is possible to extract information about the spatial distribution of the beam. At the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory, we have developed and successfully tested a simple scheme based on this principle that allows for the absolute measurement of the rms bunch length. A description of the method and the experimental results are presented.

  12. Electron bunch length measurement at the Vanderbilt FEL

    Energy Technology Data Exchange (ETDEWEB)

    Amirmadhi, F.; Brau, C.A.; Mendenhall, M. [Vanderbilt Free-Electron-Laser Center, Nashville, TN (United States)] [and others

    1995-12-31

    During the past few years, a number of experiments have been performed to demonstrate the possibility to extract the longitudinal charge distribution from spectroscopic measurements of the coherent far-infrared radiation emitted as transition radiation or synchrotron radiation. Coherent emission occurs in a spectral region where the wavelength is comparable to or longer than the bunch length, leading to an enhancement of the radiation intensity that is on the order of the number of particles per bunch, as compared to incoherent radiation. This technique is particularly useful in the region of mm and sub-mm bunch lengths, a range where streak-cameras cannot be used for beam diagnostics due to their limited time resolution. Here we report on experiments that go beyond the proof of principle of this technique by applying it to the study and optimization of FEL performance. We investigated the longitudinal bunch length of the Vanderbilt FEL by analyzing the spectrum of coherent transition radiation emitted by the electron bunches. By monitoring the bunch length while applying a bunch-compression technique, the amount of the compression could be easily observed. This enabled us to perform a systematic study of the FEL performance, especially gain and optical pulse width, as a function of the longitudinal electron distribution in the bunch. The results of this study will be presented and discussed.

  13. Observers' measurements in premetric electrodynamics: Time and radar length

    Science.gov (United States)

    Gürlebeck, Norman; Pfeifer, Christian

    2018-04-01

    The description of an observer's measurement in general relativity and the standard model of particle physics is closely related to the spacetime metric. In order to understand and interpret measurements, which test the metric structure of the spacetime, like the classical Michelson-Morley, Ives-Stilwell, Kennedy-Thorndike experiments or frequency comparison experiments in general, it is necessary to describe them in theories, which go beyond the Lorentzian metric structure. However, this requires a description of an observer's measurement without relying on a metric. We provide such a description of an observer's measurement of the fundamental quantities time and length derived from a premetric perturbation of Maxwell's electrodynamics and a discussion on how these measurements influence classical relativistic observables like time dilation and length contraction. Most importantly, we find that the modification of electrodynamics influences the measurements at two instances: the propagation of light is altered as well as the observer's proper time normalization. When interpreting the results of a specific experiment, both effects cannot be disentangled, in general, and have to be taken into account.

  14. Validation of Navigation Ultrasound for Clavicular Length Measurement

    DEFF Research Database (Denmark)

    Høj, Anders Thorsmark; Villa, Chiara; Christensen, Ole M.

    2017-01-01

    interval): approximately ± 7.5 mm, Pearson's correlation R: 0.948-0.974). Navigation ultrasound can measure clavicular length with an intra-rater reliability matching that of 3-D rendered computed tomography scans and with high validity. Its use could spread to other fields requiring accurate...... of 52.5 (range: 21-78 y) were included. Navigation ultrasound exhibited high reliability (intra-class correlation coefficient: 0.942-0.997, standard error of the mean: 0.7-2.9 mm, minimal detectable change: 2.3-8.1 mm) and validity (measurement error: 1.3%-1.8%, limits of agreement (95% confidence...

  15. The elementary school teachers’ ability in the length measurement

    Science.gov (United States)

    Julie, Hongki

    2017-09-01

    The purpose of this study was to describe the elementary school teachers' mathematical ability (1) to develop students’ activities which constructed longer than, shorter than, and as long as concepts, (2) to develop students’ activities which constructed standard unit on the length measurement, and (3) to develop a problem which used by student to construct why a conversion activity on the unit of the length was useful in the daily life after they have participated in the Realistic Mathematics Education (RME) workshops. Curry and Outhread said if teachers knew more about the growth of students’ conceptual understanding of the length, they would be better able to teach that topic [4]. Therefore, in the workshop, teachers were asked to learn more on the stages of the measurement teaching and learning process and why each stage was important. This capability was described by the results of a test which was content of four problems given to teachers after they have attended the workshop. Research subjects in this study were 14 elementary school teachers at Yogyakarta. The results of the study were as follows: (1) only four of 14 teachers who had the first ability; (2) all teachers had the second ability; and (3) all the teachers did not have the third ability.

  16. Length-free near infrared measurement of newborn malnutrition

    Science.gov (United States)

    Mustafa, Fatin Hamimi; Bek, Emily J.; Huvanandana, Jacqueline; Jones, Peter W.; Carberry, Angela E.; Jeffery, Heather E.; Jin, Craig T.; McEwan, Alistair L.

    2016-11-01

    Under-nutrition in neonates can cause immediate mortality, impaired cognitive development and early onset adult disease. Body fat percentage measured using air-displacement-plethysmography has been found to better indicate under-nutrition than conventional birth weight percentiles. However, air-displacement-plethysmography equipment is expensive and non-portable, so is not suited for use in developing communities where the burden is often the greatest. We proposed a new body fat measurement technique using a length-free model with near-infrared spectroscopy measurements on a single site of the body - the thigh. To remove the need for length measurement, we developed a model with five discrete wavelengths and a sex parameter. The model was developed using air-displacement-plethysmography measurements in 52 neonates within 48 hours of birth. We identified instrumentation required in a low-cost LED-based screening device and incorporated a receptor device that can increase the amount of light collected. This near-infrared method may be suitable as a low cost screening tool for detecting body fat levels and monitoring nutritional interventions for malnutrition in neonates and young children in resource-constrained communities.

  17. Ultrashort electron bunch length measurement with diffraction radiation deflector

    Science.gov (United States)

    Xiang, Dao; Huang, Wen-Hui

    2007-01-01

    In this paper, we propose a novel method to measure electron bunch length with a diffraction radiation (DR) deflector which is composed of a DR radiator and three beam position monitors (BPMs). When an electron beam passes through a metallic aperture which is tilted by 45 degrees with respect to its trajectory, backward DR that propagates perpendicular to the beam’s trajectory is generated which adds a transverse deflection to the beam as a result of momentum conservation. The deflection is found to be largely dependent on the bunch length and could be easily observed with a downstream BPM. Detailed investigations show that this method has wide applicability, high temporal resolution, and great simplicity.

  18. Ultrashort electron bunch length measurement with diffraction radiation deflector

    Directory of Open Access Journals (Sweden)

    Dao Xiang

    2007-01-01

    Full Text Available In this paper, we propose a novel method to measure electron bunch length with a diffraction radiation (DR deflector which is composed of a DR radiator and three beam position monitors (BPMs. When an electron beam passes through a metallic aperture which is tilted by 45 degrees with respect to its trajectory, backward DR that propagates perpendicular to the beam’s trajectory is generated which adds a transverse deflection to the beam as a result of momentum conservation. The deflection is found to be largely dependent on the bunch length and could be easily observed with a downstream BPM. Detailed investigations show that this method has wide applicability, high temporal resolution, and great simplicity.

  19. Two independent measurements of Debye lengths in doped nonpolar liquids.

    Science.gov (United States)

    Prieve, D C; Hoggard, J D; Fu, R; Sides, P J; Bethea, R

    2008-02-19

    Electric current measurements were performed between 2.5 cm x 7.5 cm parallel-plate electrodes separated by 1.2 mm of heptane doped with 0-15% w/w poly(isobutylene succinimide) (PIBS) having a molecular weight of about 1700. The rapid (microsecond) initial charging of the capacitor can be used to infer the dielectric constant of the solution. The much slower decay of current arising from the polarization of electrodes depends on the differential capacitance of the diffuse clouds of charge carriers accumulating next to each electrode and on the ohmic resistance of the fluid. Using the Gouy-Chapman model for the differential capacitance, Debye lengths of 80-600 nm were deduced that decrease with increasing concentration of PIBS. Values of the Debye lengths were confirmed by performing independent measurements of double-layer repulsion between a 6 microm polystyrene (PS) latex sphere and a PS-coated glass plate using total internal reflection microscopy in the same solutions. The charge carriers appear to be inverted PIBS micelles having apparent Stokes diameters of 20-40 nm. Dynamic light scattering reveals a broad distribution of sizes having an intensity-averaged diameter of 15 nm. This smaller size might arise (1) from overestimating the electrophoretic mobility of micelles by treating them as point charges or (2) because charged micelles are larger on average than uncharged micelles. When Faradaic reactions and zeta potentials on the electrodes can be neglected, such current versus time experiments yield values for the Debye length and ionic strength with less effort than force measurements. To obtain the concentration of charge carriers from measurements of conductivity, the mobility of the charge carriers must be known.

  20. Measurement of neutron diffusion length in heavy concrete

    International Nuclear Information System (INIS)

    Krejci, D.

    2007-04-01

    Using an aluminium sampler filled with heavy concrete the neutron diffusion length was determined, measuring thermal and fast neutrons over the whole beam hole with various threshold detectors using gold samples. These calculations should describe the neutron distribution in the whole concrete shield of the reactor and contribute to the investigation of the activation of the concrete shield using reactor parameters like operating time, power and neutron flux. Instrumentation, activation and positioning of the samples in the beam hole of the TRIGA Mark II reactor are described. (nevyjel)

  1. CT measurements of torsion and length in the lower extremities

    International Nuclear Information System (INIS)

    Waidelich, H.A.; Strecker, W.; Schneider, E.

    1992-01-01

    Complex corrective osteotomies in the lower extremities require precise preoperative planning. Fifty patients who had suffered fractures of the lower limbs and had been treated by osteosynthetic or conservative methods were studied, using a GE 9800 Quick CT; accurate and reproducible measurements of the angles of torsion of the femur and tibia were obtained. Digital images were produced to standardise the planes of measurement and to measure the length of the limb. The most important clinical measurement is the intra-individual difference of the torsional angles. Amongst normals this is 4.3 ± 2.3deg in the femur and 6.1 ± 4.5deg in the tibia. Radiation exposure was measured by a LiF-thermoluminescence dosimeter on an Alderson phantom. Skin dose was 6.3 ± 1.2 mGy and gonadal dose for females was 2.5 ± 0.3 mGy and for males 0.7 ± 0.1 mGy. (orig./GDG) [de

  2. Philtrum length and intercommissural distance measurements at mixed dentition period.

    Science.gov (United States)

    Mostafa, Mostafa; Hassib, Nehal; Sayed, Inas; Neamat, Amany; Ramzy, Magda; El-Badry, Tarek; ElGabry, Hisham; Salem, Haidy; Omar, Nada; Ismail, Amira; Ibrahim, Yousra; Shebaita, Amr; Allam, Ahmed; Mostafa, Magdy

    2018-05-01

    Anthropometric measurements of the lip and mouth are of great importance in clinical dysmorphology as well as reconstructive plastic surgery. In this study, the philtrum length (PhL) and intercommissural distance (ICmD) nomograms for Egyptian children in the mixed dentition period were established. A group of 1,338 Egyptian students in primary schools (735 boys and 603 girls) were included in the study. The students were at mixed dentition period and their ages ranged from 7 to 12 years. Anthropometric norms of PhL and ICmD were developed with significant sex difference in certain groups. A ratio between PhL and ICmD was developed. These data will help facilitate both objective and subjective evaluation of the lip and mouth for proper diagnosis of orofacial anomalies and variations as well as for ideal treatment plans. © 2018 Wiley Periodicals, Inc.

  3. Sonographic Measurement of Fetal Ear Length in Turkish Women with a Normal Pregnancy

    Directory of Open Access Journals (Sweden)

    Mucize Eriç Özdemir

    2014-12-01

    Full Text Available Background: Abnormal fetal ear length is a feature of chromosomal disorders. Fetal ear length measurement is a simple measurement that can be obtained during ultrasonographic examinations. Aims: To develop a nomogram for fetal ear length measurements in our population and investigate the correlation between fetal ear length, gestational age, and other standard fetal biometric measurements. Study Design: Cohort study. Methods: Ear lengths of the fetuses were measured in normal singleton pregnancies. The relationship between gestational age and fetal ear length in millimetres was analysed by simple linear regression. In addition, the correlation of fetal ear length measurements with biparietal diameter, head circumference, abdominal circumference, and femur length were evaluated.Ear length measurements were obtained from fetuses in 389 normal singleton pregnancies ranging between 16 and 28 weeks of gestation. Results: A nomogram was developed by linear regression analysis of the parameters ear length and gestational age. Fetal ear length (mm = y = (1.348 X gestational age-12.265, where gestational ages is in weeks. A high correlation was found between fetal ear length and gestational age, and a significant correlation was also found between fetal ear length and the biparietal diameter (r=0.962; p<0.001. Similar correlations were found between fetal ear length and head circumference, and fetal ear length and femur length. Conclusion: The results of this study provide a nomogram for fetal ear length. The study also demonstrates the relationship between ear length and other biometric measurements.

  4. Water absorption length measurement with the ANTARES optical beacon system

    International Nuclear Information System (INIS)

    Yepes-Ramirez, Harold

    2011-01-01

    ANTARES is a neutrino telescope located in the Mediterranean Sea with the aim of detecting high energy neutrinos of extra-terrestrial origin. It consists of a three dimensional array on 12 detection lines of photomultiplier tubes (PMTs) able to detect the Cherenkov light induced by muons produced in the interaction of neutrinos with the surrounding water and seabed. To reach the best angular resolution, good time and positioning calibrations are required. The propagation of Cherenkov photons strongly depends on the optical properties of the sea water, which has an impact on the reconstruction efficiency. The determination of the optical parameters, as the absorption and scattering lengths, is crucial to calculate properly the effective area and the angular resolution of the detector. The ANTARES optical beacon system consists of pulsed and fast, well controlled light sources distributed throughout the detector to carry out in situ the relative time calibration of the detector components. In this contribution we show some results on the sea water optical properties and their stability measured with the optical beacon system.

  5. Gait variability and basal ganglia disorders: stride-to-stride variations of gait cycle timing in Parkinson's disease and Huntington's disease

    Science.gov (United States)

    Hausdorff, J. M.; Cudkowicz, M. E.; Firtion, R.; Wei, J. Y.; Goldberger, A. L.

    1998-01-01

    The basal ganglia are thought to play an important role in regulating motor programs involved in gait and in the fluidity and sequencing of movement. We postulated that the ability to maintain a steady gait, with low stride-to-stride variability of gait cycle timing and its subphases, would be diminished with both Parkinson's disease (PD) and Huntington's disease (HD). To test this hypothesis, we obtained quantitative measures of stride-to-stride variability of gait cycle timing in subjects with PD (n = 15), HD (n = 20), and disease-free controls (n = 16). All measures of gait variability were significantly increased in PD and HD. In subjects with PD and HD, gait variability measures were two and three times that observed in control subjects, respectively. The degree of gait variability correlated with disease severity. In contrast, gait speed was significantly lower in PD, but not in HD, and average gait cycle duration and the time spent in many subphases of the gait cycle were similar in control subjects, HD subjects, and PD subjects. These findings are consistent with a differential control of gait variability, speed, and average gait cycle timing that may have implications for understanding the role of the basal ganglia in locomotor control and for quantitatively assessing gait in clinical settings.

  6. Generalization of improved step length symmetry from treadmill to overground walking in persons with stroke and hemiparesis†

    Science.gov (United States)

    Savin, Douglas N.; Morton, Susanne M.; Whitall, Jill

    2013-01-01

    Objectives Determine whether adaptation to a swing phase perturbation during gait transferred from treadmill to overground walking, the rate of overground deadaptation, and whether overground aftereffects improved step length asymmetry in persons with hemiparetic stroke and gait asymmetry. Methods Ten participants with stroke and hemiparesis and 10 controls walked overground on an instrumented gait mat, adapted gait to a swing phase perturbation on a treadmill, then walked overground on the gait mat again. Outcome measures, primary: overground step length symmetry, rates of treadmill step length symmetry adaptation and overground step length symmetry deadaptation; secondary: overground gait velocity, stride length, and stride cycle duration. Results Step length symmetry aftereffects generalized to overground walking and adapted at a similar rate on the treadmill in both groups. Aftereffects decayed at a slower rate overground in participants with stroke and temporarily improved overground step length asymmetry. Both groups’ overground gait velocity increased post adaptation due to increased stride length and decreased stride duration. Conclusions Stroke and hemiparesis do not impair generalization of step length symmetry changes from adapted treadmill to overground walking, but prolong overground aftereffects. Significance Motor adaptation during treadmill walking may be an effective treatment for improving overground gait asymmetries post-stroke. PMID:24286858

  7. Partial body weight support treadmill training speed influences paretic and non-paretic leg muscle activation, stride characteristics, and ratings of perceived exertion during acute stroke rehabilitation.

    Science.gov (United States)

    Burnfield, Judith M; Buster, Thad W; Goldman, Amy J; Corbridge, Laura M; Harper-Hanigan, Kellee

    2016-06-01

    Intensive task-specific training is promoted as one approach for facilitating neural plastic brain changes and associated motor behavior gains following neurologic injury. Partial body weight support treadmill training (PBWSTT), is one task-specific approach frequently used to improve walking during the acute period of stroke recovery (training parameters and physiologic demands during this early recovery phase. To examine the impact of four walking speeds on stride characteristics, lower extremity muscle demands (both paretic and non-paretic), Borg ratings of perceived exertion (RPE), and blood pressure. A prospective, repeated measures design was used. Ten inpatients post unilateral stroke participated. Following three familiarization sessions, participants engaged in PBWSTT at four predetermined speeds (0.5, 1.0, 1.5 and 2.0mph) while bilateral electromyographic and stride characteristic data were recorded. RPE was evaluated immediately following each trial. Stride length, cadence, and paretic single limb support increased with faster walking speeds (p⩽0.001), while non-paretic single limb support remained nearly constant. Faster walking resulted in greater peak and mean muscle activation in the paretic medial hamstrings, vastus lateralis and medial gastrocnemius, and non-paretic medial gastrocnemius (p⩽0.001). RPE also was greatest at the fastest compared to two slowest speeds (ptraining at the slowest speeds. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Persistent fluctuations in stride intervals under fractal auditory stimulation

    NARCIS (Netherlands)

    Marmelat, V.C.M.; Torre, K.; Beek, P.J.; Daffertshofer, A.

    2014-01-01

    Stride sequences of healthy gait are characterized by persistent long-range correlations, which become anti-persistent in the presence of an isochronous metronome. The latter phenomenon is of particular interest because auditory cueing is generally considered to reduce stride variability and may

  9. Measurement of electron beam bunch phase length by rectangular cavities

    International Nuclear Information System (INIS)

    Afanas'ev, V.D.; Rudychev, V.G.; Ushakov, V.I.

    1976-01-01

    An analysis of a phase length of electron bunches with the help of crossed rectangular resonators with the Hsub(102) oscillation type has been made. It has been shown that the electron coordinates after the duplex resonator are described by an ellipse equation for a non-modulated beam. An influence of the initial energy spread upon the electron motion has been studied. It has been ascertained that energy modulation of the electron beam results in displacement of each electron with respect to the ellipse which is proportional to modulation energy, i.e. an error in determination of the phase length of an electron bunch is proportional to the beam energy spread. Relations have been obtained which enable to find genuine values of phases of the analyzed electrons with an accuracy up to linear multipliers

  10. Measurement of diffusion length of thermal neutrons in concrete

    International Nuclear Information System (INIS)

    Moser, M.

    2007-04-01

    The diffusion length of neutrons with a medium energy < 0.025 eV in concrete were determined using 4π-β detector and gamma detectors. Then it was possible to determine how deep can neutrons penetrate diverse concrete construction parts in a reactor in operation, with this method the dismantling process of a reactor can be planned in terms of what parts can be removed without danger and what parts can be assumed still are activated. (nevyjel)

  11. Stride time synergy in relation to walking during dual task

    DEFF Research Database (Denmark)

    Læssøe, Uffe; Madeleine, Pascal

    2012-01-01

    point of view elemental and performance variables may represent good and bad components of variability [2]. In this study we propose that the gait pattern can be seen as an on-going movement synergy in which each stride is corrected by the next stride (elemental variables) to ensure a steady gait...... (performance variable). AIM: The aim of this study was to evaluate stride time synergy and to identify good and bad stride variability in relation to walking during dual task. METHODS: Thirteen healthy young participants walked along a 2x5 meter figure-of-eight track at a self-selected comfortable speed...... with a positive slope going through the mean of the strides, and bad variance with respect to a similar line with a negative slope. The general variance coefficient (CV%) was also computed. The effect of introducing a concurrent cognitive task (dual task: counting backwards in sequences of 7) was evaluated...

  12. Dynamic Length Metrology (DLM) for measurements with sub-micrometre uncertainty in a production environment

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo; Hansen, Hans Nørgaard; Hattel, Jesper Henri

    2016-01-01

    Conventional length metrology for traceable accurate measurements requires costly temperature controlled facilities, long waiting time for part acclimatisation, and separate part material characterisation. This work describes a method called Dynamic Length Metrology (DLM) developed to achieve sub...

  13. Effect of Different Training Methods on Stride Parameters in Speed Maintenance Phase of 100-m Sprint Running.

    Science.gov (United States)

    Cetin, Emel; Hindistan, I Ethem; Ozkaya, Y Gul

    2018-05-01

    Cetin, E, Hindistan, IE, Ozkaya, YG. Effect of different training methods on stride parameters in speed maintenance phase of 100-m sprint running. J Strength Cond Res 32(5): 1263-1272, 2018-This study examined the effects of 2 different training methods relevant to sloping surface on stride parameters in speed maintenance phase of 100-m sprint running. Twenty recreationally active students were assigned into one of 3 groups: combined training (Com), horizontal training (H), and control (C) group. Com group performed uphill and downhill training on a sloping surface with an angle of 4°, whereas H group trained on a horizontal surface, 3 days a week for 8 weeks. Speed maintenance and deceleration phases were divided into distances with 10-m intervals, and running time (t), running velocity (RV), step frequency (SF), and step length (SL) were measured at preexercise, and postexercise period. After 8 weeks of training program, t was shortened by 3.97% in Com group, and 2.37% in H group. Running velocity also increased for totally 100 m of running distance by 4.13 and 2.35% in Com, and H groups, respectively. At the speed maintenance phase, although t and maximal RV (RVmax) found to be statistically unaltered during overall phase, t was found to be decreased, and RVmax was preceded by 10 m in distance in both training groups. Step length was increased at 60-70 m, and SF was decreased at 70-80 m in H group. Step length was increased with concomitant decrease in SF at 80-90 m in Com group. Both training groups maintained the RVmax with a great percentage at the speed maintenance phase. In conclusion, although both training methods resulted in an increase in running time and RV, Com training method was more prominently effective method in improving RV, and this improvement was originated from the positive changes in SL during the speed maintaining phase.

  14. Statistical length of DNA based on AFM image measured by a computer

    International Nuclear Information System (INIS)

    Chen Xinqing; Qiu Xijun; Zhang Yi; Hu Jun; Wu Shiying; Huang Yibo; Ai Xiaobai; Li Minqian

    2001-01-01

    Taking advantage of image processing technology, the contour length of DNA molecule was measured automatically by a computer. Based on the AFM image of DNA, the topography of DNA was simulated into a curve. Then the DNA length was measured automatically by inserting mode. It was shown that the experimental length of a naturally deposited DNA (180.4 +- 16.4 nm) was well consistent with the theoretical length (185.0 nm). Comparing to other methods, the present approach had advantages of precision and automatism. The stretched DNA was also measured. It present approach had advantages of precision and automatism. The stretched DNA was also measured. It was shown that the experimental length (343.6 +- 20.7 nm) was much longer than the theoretical length (307.0 nm). This result indicated that the stretching process had a distinct effect on the DNA length. However, the method provided here avoided the DNA-stretching effect

  15. An induction sensor for measuring rectilinear movements of substantial length

    International Nuclear Information System (INIS)

    Jaudou, Yves.

    1973-01-01

    The invention is characterized in that it comprises the steps of making one end of a magnetic core integral with the objet, the movements of which are to be measured. The core has the shape of an isoscele prism the base surface of which slides within two aligned coils contained in two adjacent arms of an A-C operated Wheatstone bridge. The impedances in the W-bridge other two arms is adjusted in order that the Wheatstone bridge be balanced at a given position of the object. The movement of the object is measured from the latter given position through the potential difference, proportional to said movement developed between two opposite apices E and D of the bridge, the latter being fed with AC between the other two apices (A and B). This can be applied to the measurement of the movements of irradiation capsules in a nuclear reactor [fr

  16. The reliability of transabdominal cervical length measurement in a low-risk obstetric population: Comparison with transvaginal measurement.

    Science.gov (United States)

    Peng, Cheng-Ran; Chen, Chie-Pein; Wang, Kuo-Gon; Wang, Liang-Kai; Chen, Chen-Yu; Chen, Yi-Yung

    2015-04-01

    To determine the correlation between transabdominal (TA) and transvaginal (TV) cervical length measurement in a low-risk obstetric population in Taiwan. Women with a singleton pregnancy between 20 weeks and 24 weeks of gestation underwent postvoid TA and TV cervical length measurements. Differences between the measurements obtained using the two methods were evaluated. Two hundred and five women agreed to participate in the study. Paired TA and TV measurements were obtained in 174 women. The mean TA cervical length was 36.0 ± 4.9 mm and the mean TV cervical length was 37.6 ± 5.4 mm. The mean TA cervical length was shorter than the mean TV cervical length by 1.6 mm. The 5(th) percentile of TA and TV cervical length was 29 mm and 29.1 mm, respectively. The discrepancies between the two methods were not significantly correlated with maternal body mass index (BMI). All women with TV cervical length women in the present study, and the TA cervical length was closely correlated with the TV cervical length. The use of TA ultrasound could be an effective initial tool for cervical length screening in low-risk pregnant women. TA cervical length TV ultrasound. Copyright © 2015. Published by Elsevier B.V.

  17. Normal standards for kidney length as measured with US in premature infants

    International Nuclear Information System (INIS)

    Schlesinger, A.E.; Hedlund, G.L.; Pierson, W.P.; Null, D.M.

    1986-01-01

    In order to develop normal standards for kidney length in premature infants, the authors measured kidney length by US imaging in 39 (to date) premature infants less than 72 hours old and without known renal disease. Kidney length was compared with four different parameters of body size, including gestational age, birth weight, birth length, and body surface area. Similar standards have been generated previously for normal renal length as measured by US imaging in full-term infants and older children. These standards have proven utility in cases of congenital and acquired disorders that abnormally increase or decrease renal size. Scatter plots of kidney length versus body weight and kidney length versus body surface area conformed well to a logarithmic distribution, with a high correlation coefficient and close-fitting 95% confidence limits (SEE = 2.05)

  18. Laser interferometry in length measurement. Proceedings. Laserinterferometrie in der Laengenmesstechnik. Vortraege

    Energy Technology Data Exchange (ETDEWEB)

    1985-01-01

    Wavelength-stabilized lasers for length measurement, measurements of the refractive index of air, laser interferometers, acceptance tests of laser interferometer systems, the Michelson interferometer with semiconductor laser, and the state of the art of optical gyroscopes for angular position measurement are described in the general section. The examples of laser interferometer applications in production engineering comprise automatic acceptance testing of coordinate measuring systems, simultaneous laser measurements of the position and the pitching, yansing and rolling angles along a measuring line, a 3D-interferometer length measuring system, the calibration of standard measures, angular position measurements, straightness measurements, and laser interferometers as installed length measuring systems in machine tools and measuring machinery. There are no separate records of the 13 lectures presented at the meeting. (DG).

  19. Utility of telomere length measurements for age determination of humpback whales

    Directory of Open Access Journals (Sweden)

    Morten Tange Olsen

    2014-12-01

    Full Text Available This study examines the applicability of telomere length measurements by quantitative PCR as a tool for minimally invasive age determination of free-ranging cetaceans. We analysed telomere length in skin samples from 28 North Atlantic humpback whales (Megaptera novaeangliae, ranging from 0 to 26 years of age. The results suggested a significant correlation between telomere length and age in humpback whales. However, telomere length was highly variable among individuals of similar age, suggesting that telomere length measured by quantitative PCR is an imprecise determinant of age in humpback whales. The observed variation in individual telomere length was found to be a function of both experimental and biological variability, with the latter perhaps reflecting patterns of inheritance, resource allocation trade-offs, and stochasticity of the marine environment.

  20. Automatic measurement of axial length of human eye using three-dimensional magnetic resonance imaging

    International Nuclear Information System (INIS)

    Watanabe, Masaki; Kiryu, Tohru

    2011-01-01

    The measurement of axial length and the evaluation of three dimensional (3D) form of an eye are essential to evaluate the mechanism of myopia progression. We propose a method of automatic measurement of axial length including adjustment of the pulse sequence of short-term scan which could suppress influence of eyeblink, using a magnetic resonance imaging (MRI) which acquires 3D images noninvasively. Acquiring T 2 -weighted images with 3.0 tesla MRI device and eight-channel phased-array head coil, we extracted left and right eye ball images, and then reconstructed 3D volume. The surface coordinates were calculated from 3D volume, fitting the ellipsoid model coordinates with the surface coordinates, and measured the axial length automatically. Measuring twenty one subjects, we compared the automatically measured values of axial length with the manually measured ones, then confirmed significant elongation in the axial length of myopia compared with that of emmetropia. Furthermore, there were no significant differences (P<0.05) between the means of automatic measurements and the manual ones. Accordingly, the automatic measurement process of axial length could be a tool for the elucidation of the mechanism of myopia progression, which would be suitable for evaluating the axial length easily and noninvasively. (author)

  1. Measuring minority-carrier diffusion length using a Kelvin probe force microscope

    International Nuclear Information System (INIS)

    Shikler, R.; Fried, N.; Meoded, T.; Rosenwaks, Y.

    2000-01-01

    A method based on Kelvin probe force microscopy for measuring minority-carrier diffusion length in semiconductors is described. The method is based on measuring the surface photovoltage between the tip of an atomic force microscope and the surface of an illuminated semiconductor junction. The photogenerated carriers diffuse to the junction and change the contact potential difference between the tip and the sample, as a function of the distance from the junction. The diffusion length L is then obtained by fitting the measured contact potential difference using the minority-carrier continuity equation. The method was applied to measurements of electron diffusion length in GaP pn and Schottky junctions. The measured diffusion length was found to be ∼2 μm, in good agreement with electron beam induced current measurements

  2. STRIDE: Species Tree Root Inference from Gene Duplication Events.

    Science.gov (United States)

    Emms, David M; Kelly, Steven

    2017-12-01

    The correct interpretation of any phylogenetic tree is dependent on that tree being correctly rooted. We present STRIDE, a fast, effective, and outgroup-free method for identification of gene duplication events and species tree root inference in large-scale molecular phylogenetic analyses. STRIDE identifies sets of well-supported in-group gene duplication events from a set of unrooted gene trees, and analyses these events to infer a probability distribution over an unrooted species tree for the location of its root. We show that STRIDE correctly identifies the root of the species tree in multiple large-scale molecular phylogenetic data sets spanning a wide range of timescales and taxonomic groups. We demonstrate that the novel probability model implemented in STRIDE can accurately represent the ambiguity in species tree root assignment for data sets where information is limited. Furthermore, application of STRIDE to outgroup-free inference of the origin of the eukaryotic tree resulted in a root probability distribution that provides additional support for leading hypotheses for the origin of the eukaryotes. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  3. Effects of diffraction and target finite size on coherent transition radiation spectra in bunch length measurements

    Energy Technology Data Exchange (ETDEWEB)

    Castellano, M.; Cianchi, A.; Verzilov, V.A. [Istituto Nazionale di Fisica Nucleare, Frascati, RM (Italy). Laboratori Nazionali di Frascati; Orlandi, G. [Istituto Nazionale di Fisica Nucleare, Rome (Italy)]|[Rome Univ., Tor Vergata, Rome (Italy)

    1999-07-01

    Effects of diffraction and the size of the target on TR in the context of CTR-based bunch length measurements are studied on the basis of Kirchhoff diffraction theory. Spectra of TR from the finite-size target for several schemes of measurements are calculated in the far-infrared region showing strong distortion at low frequencies. Influence of the effect on the accuracy of bunch length measurements is estimated.

  4. Utility of telomere length measurements for age determination of humpback whales

    NARCIS (Netherlands)

    Olsen, Morten T.; Robbins, Jooke; Bérubé, Martine; Rew, Mary Beth; Palsboll, Per

    2014-01-01

    This study examines the applicability of telomere length measurements by quantitative PCR as a tool for minimally invasive age determination of free-ranging cetaceans. We analysed telomere length in skin samples from 28 North Atlantic humpback whales (Megaptera novaeangliae), ranging from 0 to 26

  5. Blood and dried blood spot telomere length measurement by qPCR: assay considerations.

    Directory of Open Access Journals (Sweden)

    DeAnna L Zanet

    Full Text Available Measurement of telomere length is crucial for the study of telomere maintenance and its role in molecular pathophysiology of diseases and in aging. Several methods are used to measure telomere length, the choice of which usually depends on the type and size of sample to be assayed, as well as cost and throughput considerations. The goal of this study was to investigate the factors that may influence the reliability of qPCR-based relative telomere length measurements in whole blood. Day to day intra-individual variability, types of blood anticoagulant, sample storage conditions, processing and site of blood draw were investigated. Two qPCR-based methods to measure telomere length (monoplex vs. multiplex were also investigated and showed a strong correlation between them. Freezing and thawing of the blood and storage of the blood at 4°C for up to 4 days did not affect telomere length values. Telomere lengths in dried blood spots were significantly higher than both whole blood and peripheral mononuclear blood cells, and were highly correlated with both. We found that telomere length measurements were significantly higher in dried blood spots collected directly from fingertip prick compared to dried blood spots prepared with anticoagulated whole blood collected from the finger, and non-blotted whole blood taken from both finger and arm venipuncture. This suggests that DNA from cells blotted on paper is not equivalent to that collected from venipuncture whole blood, and caution should be taken when comparing between blood sample types.

  6. Association between stride time fractality and gait adaptability during unperturbed and asymmetric walking.

    Science.gov (United States)

    Ducharme, Scott W; Liddy, Joshua J; Haddad, Jeffrey M; Busa, Michael A; Claxton, Laura J; van Emmerik, Richard E A

    2018-04-01

    Human locomotion is an inherently complex activity that requires the coordination and control of neurophysiological and biomechanical degrees of freedom across various spatiotemporal scales. Locomotor patterns must constantly be altered in the face of changing environmental or task demands, such as heterogeneous terrains or obstacles. Variability in stride times occurring at short time scales (e.g., 5-10 strides) is statistically correlated to larger fluctuations occurring over longer time scales (e.g., 50-100 strides). This relationship, known as fractal dynamics, is thought to represent the adaptive capacity of the locomotor system. However, this has not been tested empirically. Thus, the purpose of this study was to determine if stride time fractality during steady state walking associated with the ability of individuals to adapt their gait patterns when locomotor speed and symmetry are altered. Fifteen healthy adults walked on a split-belt treadmill at preferred speed, half of preferred speed, and with one leg at preferred speed and the other at half speed (2:1 ratio asymmetric walking). The asymmetric belt speed condition induced gait asymmetries that required adaptation of locomotor patterns. The slow speed manipulation was chosen in order to determine the impact of gait speed on stride time fractal dynamics. Detrended fluctuation analysis was used to quantify the correlation structure, i.e., fractality, of stride times. Cross-correlation analysis was used to measure the deviation from intended anti-phasing between legs as a measure of gait adaptation. Results revealed no association between unperturbed walking fractal dynamics and gait adaptability performance. However, there was a quadratic relationship between perturbed, asymmetric walking fractal dynamics and adaptive performance during split-belt walking, whereby individuals who exhibited fractal scaling exponents that deviated from 1/f performed the poorest. Compared to steady state preferred walking

  7. Measurement of molecular length of self-assembled monolayer probed by localized surface plasmon resonance

    Science.gov (United States)

    Ito, Juri; Kajikawa, Kotaro

    2016-02-01

    We propose a method to measure the variation of the molecular length of self-assembled monolayers (SAMs) when it is exposed to solutions at different pH conditions. The surface immobilized gold nanospheres (SIGNs) shows strong absorption peak at the wavelengths of 600-800 nm when p-polarized light is illuminated. The peak wavelength depends on the length of the gap distance between the SIGNs and the substrate. The gap is supported by the SAM molecules. According to the analytical calculation based on multiple expansion, the relation between the peak wavelength of the SIGN structures and the gap distance is calculated, to evaluate the molecular length of the SAM through the optical absorption spectroscopy for the SIGN structures. The molecular length of the SIGN structure was measured in air, water, acidic, and basic solutions. It was found that the molecular lengths are longer in acidic solutions.

  8. Slip length measurement of confined air flow on three smooth surfaces.

    Science.gov (United States)

    Pan, Yunlu; Bhushan, Bharat; Maali, Abdelhamid

    2013-04-02

    An experimental measurement of the slip length of air flow close to three different solid surfaces is presented. The substrate was driven by a nanopositioner moving toward an oscillating glass sphere glued to an atomic force microscopy (AFM) cantilever. A large separation distance was used to get more effective data. The slip length value was obtained by analyzing the amplitude and phase data of the cantilever. The measurements show that the slip length does not depend on the oscillation amplitude of the cantilever. Because of the small difference among the slip lengths of the three surfaces, a simplified analysis method was used. The results show that on glass, graphite, and mica surfaces the slip lengths are 98, 234, and 110 nm, respectively.

  9. Measurements of Turbulent Flame Speed and Integral Length Scales in a Lean Stationary Premixed Flame

    OpenAIRE

    Klingmann, Jens; Johansson, Bengt

    1998-01-01

    Turbulent premixed natural gas - air flame velocities have been measured in a stationary axi-symmetric burner using LDA. The flame was stabilized by letting the flow retard toward a stagnation plate downstream of the burner exit. Turbulence was generated by letting the flow pass through a plate with drilled holes. Three different hole diameters were used, 3, 6 and 10 mm, in order to achieve different turbulent length scales. Turbulent integral length scales were measured using two-point LD...

  10. Preliminary result of bunch length measurement using a modified Michelson interferometer

    International Nuclear Information System (INIS)

    Lin Xuling; Luo Feng; Bei Hua; Dai Zhimin; Chinese Academy of Sciences, Beijing; Zhang Jianbing; Lu Shanliang; Yu Tiemin

    2009-01-01

    Based on the femtosecond accelerator device which was built at the Shanghai Institute of Applied Physics (SINAP), recently a modified far infrared Michelson interferometer has been developed to measure the length of electron bunches via the optical autocorrelation method. Compared with our former normal Michelson interferometer, we use a hollow retroreflector instead of a flat mirror as the reflective mirror. The experimental setup and results of the bunch length measurement will be described in this paper. (authors)

  11. Air refractometry in a length comparator and the response to changes in the measurement environment

    Energy Technology Data Exchange (ETDEWEB)

    Pieles, H

    1998-11-01

    Two different interference refractometers and one air parameter set-up are simultaneously operated in a temperature-stabilized casing of a length comparator. They allow absolute and relative measurements and calculations, respectively of the refractive index of air to be carried out for continuous interferometric length measurements. Measurement results are presented which were obtained under optimized environmental conditions. In addition, sources of disturbances are described which can significantly influence the measurements of the refractive index of air, and consequently may influence the accuracy of interferometric displacement measurements. (orig.)

  12. [Shushu (ancient Chinese numerology) in Lingshu: Gudu (Miraculous Pivot: Bone-Length Measurement)].

    Science.gov (United States)

    Zhuo, Lian-Shi

    2010-10-01

    Lingshu: Gudu (Miraculous Pivot: Bone-Length Measurement) is compared with literatures concerning the Shushu (ancient Chinese numerology) of the Qin Dynasty (221 B. C. - 206 B. C. ) and the Han Dynasty (206 B. C.-220 A. D.) in this article. And it is discovered that "the number of heaven and earth" in Yijing (The Book of Change) was implied in the bone-length measurement. The theory of Shushu is hidden in the sized of head, neck, chest, abdomen, back and 4 extremities according to the measurement. The meaning of establishment of bone-length measurement, which is found to have universality, laid in setting down the measurement of meridians. And it is the origin of the proportional measurement of locating acupoints. Checked with the theory of Shushu, errors in the description of bone-length measurement could also be found in Lingshu: Gudu (Miraculous Pivot: Bone-Length Measurement) of the present edition, which is helpful for the modern study on the measurement.

  13. A comparative analysis of spectral exponent estimation techniques for 1/f(β) processes with applications to the analysis of stride interval time series.

    Science.gov (United States)

    Schaefer, Alexander; Brach, Jennifer S; Perera, Subashan; Sejdić, Ervin

    2014-01-30

    The time evolution and complex interactions of many nonlinear systems, such as in the human body, result in fractal types of parameter outcomes that exhibit self similarity over long time scales by a power law in the frequency spectrum S(f)=1/f(β). The scaling exponent β is thus often interpreted as a "biomarker" of relative health and decline. This paper presents a thorough comparative numerical analysis of fractal characterization techniques with specific consideration given to experimentally measured gait stride interval time series. The ideal fractal signals generated in the numerical analysis are constrained under varying lengths and biases indicative of a range of physiologically conceivable fractal signals. This analysis is to complement previous investigations of fractal characteristics in healthy and pathological gait stride interval time series, with which this study is compared. The results of our analysis showed that the averaged wavelet coefficient method consistently yielded the most accurate results. Class dependent methods proved to be unsuitable for physiological time series. Detrended fluctuation analysis as most prevailing method in the literature exhibited large estimation variances. The comparative numerical analysis and experimental applications provide a thorough basis for determining an appropriate and robust method for measuring and comparing a physiologically meaningful biomarker, the spectral index β. In consideration of the constraints of application, we note the significant drawbacks of detrended fluctuation analysis and conclude that the averaged wavelet coefficient method can provide reasonable consistency and accuracy for characterizing these fractal time series. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. The Length of a Pestle: A Class Exercise in Measurement and Statistical Analysis.

    Science.gov (United States)

    O'Reilly, James E.

    1986-01-01

    Outlines the simple exercise of measuring the length of an object as a concrete paradigm of the entire process of making chemical measurements and treating the resulting data. Discusses the procedure, significant figures, measurement error, spurious data, rejection of results, precision and accuracy, and student responses. (TW)

  15. Tyre contact length on dry and wet road surfaces measured by three-axial accelerometer

    Science.gov (United States)

    Matilainen, Mika; Tuononen, Ari

    2015-02-01

    We determined the tyre contact length on dry and wet roads by measuring the accelerations of the inner liner with a three-axial accelerometer. The influence of the tyre pressure, driving velocity, and tread depth on the contact length was studied in both types of road surface conditions. On dry asphalt the contact length was almost constant, regardless of the driving velocity. On wet asphalt the presence of water could be detected even at low driving velocities (e.g. 20 km/h for a worn tyre) as the contact length began to decrease from that found in the dry asphalt situation. In addition to improving the performance of active safety systems and driver warning systems, the contact length information could be beneficial for classifying and studying the aquaplaning behaviour of tyres.

  16. Optimal stride frequencies in running at different speeds

    NARCIS (Netherlands)

    Van Oeveren, Ben T.; De Ruiter, Cornelis J.; Beek, Peter J.; Van Dieën, Jaap H.

    2017-01-01

    During running at a constant speed, the optimal stride frequency (SF) can be derived from the u-shaped relationship between SF and heart rate (HR). Changing SF towards the optimum of this relationship is beneficial for energy expenditure and may positively change biomechanics of running. In the

  17. Paediatric renal length measurements from ultrasound and DMSA scans: does clinical practice reflect theoretical normal values?

    International Nuclear Information System (INIS)

    Que, L.; Rutland, M.D.; Hassan, I.M.

    1999-01-01

    Full text: Renal length measurement is a routine part of ultrasound examination in children and those results are plotted on a normogram style graph, so that each child's results are compared to a normal range (mean ± 2 S.D.). Renal length measurements from the posterior oblique views of dimercaptosuccinic acid (DMSA) scans in our department have not always correlated well with the ultrasound measurements on the same patients. Renal lengths from the DMSA scans of 120 patients with apparently normal kidneys were recorded and used to generate a normogram of renal length at different ages (0.5-7 years). This DMSA normogram was compared to the ultrasound (US) normogram used in the Paediatric Radiology Department, and it showed slight differences in renal lengths (3-8 mm), but that the US normogram had smaller coefficients of variation (US = 6.6%, NM 8.3%), implying a 'tighter' normal range. 39 of these patients had DMSA and ultrasound measurements of renal length within 3 months, and these were studied first by calculating the mean and CV values for different age groups, and then by plotting individual renal lengths on the appropriate normograms. The measured data produced much greater variability in the ultrasound measurements than the DTPA measurements, and the individual points produced 4/78 (5.1%) abnormal results for DMSA, but 21/78 (26.9%) abnormal results for ultrasound. Thus, in routine clinical use, using patients with apparently normal kidneys, ultrasound was unable to match the 'normal range' set by their current normogram, but the nuclear medicine showed 5.1% of values outside the normal (DMSA) range, which was completely appropriate for a range of ± 2 standard deviations

  18. Persistent fluctuations in stride intervals under fractal auditory stimulation.

    Directory of Open Access Journals (Sweden)

    Vivien Marmelat

    Full Text Available Stride sequences of healthy gait are characterized by persistent long-range correlations, which become anti-persistent in the presence of an isochronous metronome. The latter phenomenon is of particular interest because auditory cueing is generally considered to reduce stride variability and may hence be beneficial for stabilizing gait. Complex systems tend to match their correlation structure when synchronizing. In gait training, can one capitalize on this tendency by using a fractal metronome rather than an isochronous one? We examined whether auditory cues with fractal variations in inter-beat intervals yield similar fractal inter-stride interval variability as isochronous auditory cueing in two complementary experiments. In Experiment 1, participants walked on a treadmill while being paced by either an isochronous or a fractal metronome with different variation strengths between beats in order to test whether participants managed to synchronize with a fractal metronome and to determine the necessary amount of variability for participants to switch from anti-persistent to persistent inter-stride intervals. Participants did synchronize with the metronome despite its fractal randomness. The corresponding coefficient of variation of inter-beat intervals was fixed in Experiment 2, in which participants walked on a treadmill while being paced by non-isochronous metronomes with different scaling exponents. As expected, inter-stride intervals showed persistent correlations similar to self-paced walking only when cueing contained persistent correlations. Our results open up a new window to optimize rhythmic auditory cueing for gait stabilization by integrating fractal fluctuations in the inter-beat intervals.

  19. Persistent fluctuations in stride intervals under fractal auditory stimulation.

    Science.gov (United States)

    Marmelat, Vivien; Torre, Kjerstin; Beek, Peter J; Daffertshofer, Andreas

    2014-01-01

    Stride sequences of healthy gait are characterized by persistent long-range correlations, which become anti-persistent in the presence of an isochronous metronome. The latter phenomenon is of particular interest because auditory cueing is generally considered to reduce stride variability and may hence be beneficial for stabilizing gait. Complex systems tend to match their correlation structure when synchronizing. In gait training, can one capitalize on this tendency by using a fractal metronome rather than an isochronous one? We examined whether auditory cues with fractal variations in inter-beat intervals yield similar fractal inter-stride interval variability as isochronous auditory cueing in two complementary experiments. In Experiment 1, participants walked on a treadmill while being paced by either an isochronous or a fractal metronome with different variation strengths between beats in order to test whether participants managed to synchronize with a fractal metronome and to determine the necessary amount of variability for participants to switch from anti-persistent to persistent inter-stride intervals. Participants did synchronize with the metronome despite its fractal randomness. The corresponding coefficient of variation of inter-beat intervals was fixed in Experiment 2, in which participants walked on a treadmill while being paced by non-isochronous metronomes with different scaling exponents. As expected, inter-stride intervals showed persistent correlations similar to self-paced walking only when cueing contained persistent correlations. Our results open up a new window to optimize rhythmic auditory cueing for gait stabilization by integrating fractal fluctuations in the inter-beat intervals.

  20. The accuracy of axial length measurements in cases of macula-off retinal detachment.

    Science.gov (United States)

    Abou-Shousha, Mohsen; Helaly, Hany Ahmed; Osman, Ihab Mohamed

    2016-04-01

    To assess the accuracy of axial length measurements in cases of macula-off retinal detachment using different methods (optical biometry, A-scan ultrasound, and combined applanation vector-A/B-scan biometry). This prospective clinical study included 100 eyes of 100 patients who underwent vitrectomy alone or phacovitrectomy for macula-off retinal detachment. All patients included signed an informed consent. Preoperative examination of the patients included recording the axial length measurements using optical biometry, A-scan ultrasound, and combined applanation vector-A/B-scan biometry. The mean postoperative IOLMaster axial length after macular reattachment was 26.11 ± 2.91 mm. The mean preoperative IOLMaster axial length with macula-off was 25.32 ± 2.72 mm. The mean preoperative A-scan axial length with macula-off was 25.29 ± 2.80 mm. The mean preoperative vector-A/B-scan axial length with macula-off was 26.03 ± 2.90 mm. The preoperative vector-A/B-scan mean absolute error was 0.59 ± 0.48 D (range, 0.10-2.25 D). Regular methods (optical biometry and A-scan biometry) of measuring the axial length in cases with a detached macula proved to be variable and less accurate. The vector-A/B-scan offered good measurements of the actual axial length in the patients. This was reflected on more accurate postoperative refractive outcome. Copyright © 2016 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.

  1. 16 CFR 500.12 - Measurement of commodities by length and width, how expressed.

    Science.gov (United States)

    2010-01-01

    ... square foot (929 cm2) be expressed in terms of length and width in linear measure. The customary inch... of 1 square foot (929 cm2) or more, but less than 4 square feet (37.1 dm2), be expressed in terms of... (10.16 cm) or less, the declaration of net quantity shall be expressed in terms of width and length in...

  2. Technique for the focal-length measurement of positive lenses using Fizeau interferometry

    International Nuclear Information System (INIS)

    Pavan Kumar, Yeddanapudi; Chatterjee, Sanjib

    2009-01-01

    We present what we believe is a new technique for the focal-length measurement of positive lenses using Fizeau interferometery. The technique utilizes the Gaussian lens equation. The image distance is measured interferometrically in terms of the radius of curvature of the image-forming wavefront emerging from the lens. The radii of curvature of the image-forming wavefronts corresponding to two different axial object positions of known separation are measured. The focal length of the lens is determined by solving the equations obtained using the Gaussian lens equation for the two object positions. Results obtained for a corrected doublet lens of a nominal focal length of 200.0 mm with a measurement uncertainty of ±2.5% is presented

  3. Reliability of linear distance measurement for dental implant length with standardized periapical radiographs

    International Nuclear Information System (INIS)

    Wakoh, Mamoru; Harada, Takuya; Otonari, Takamichi

    2006-01-01

    The purpose of this study was to investigate the accuracy of distance measurements of implant length based on periapical radiographs compared with that of other modalities. We carried out an experimental trial to compare precision in distance measurement. Dental implant fixtures were buried in the canine and first molar regions. These were then subjected to periapical (PE) radiography, panoramic (PA) radiography conventional (CV) and medical computed (CT) tomography. The length of the implant fixture on each film was measured by nine observers and degree of precision was statistically analyzed. The precision of both PE radiographs and CT tomograms was closest at the highest level. Standardized PE radiography, in particular, was superior to CT tomography in the first molar region. This suggests that standardized PE radiographs should be utilized as a reliable modality for longitudinal and linear distance measurement, depending on implant length at local implantation site. (author)

  4. Influence of crack length on crack depth measurement by an alternating current potential drop technique

    International Nuclear Information System (INIS)

    Raja, Manoj K; Mahadevan, S; Rao, B P C; Behera, S P; Jayakumar, T; Raj, Baldev

    2010-01-01

    An alternating current potential drop (ACPD) technique is used for sizing depth of surface cracks in metallic components. Crack depth estimations are prone to large deviations when ACPD measurements are made on very shallow and finite length cracks, especially in low conducting materials such as austenitic stainless steel (SS). Detailed studies have been carried out to investigate the influence of crack length and aspect ratio (length to depth) on depth estimation by performing measurements on electric discharge machined notches with the aspect ratio in the range of 1 to 40 in SS plates. In notches with finite length, an additional path for current to flow through the surface along the length is available causing the notch depths to be underestimated. The experimentally observed deviation in notch depth estimates is explained from a simple mathematical approach using the equivalent resistive circuit model based on the additional path available for the current to flow. A scheme is proposed to accurately measure the depth of cracks with finite lengths in SS components

  5. Stride-related rein tension patterns in walk and trot in the ridden horse.

    Science.gov (United States)

    Egenvall, Agneta; Roepstorff, Lars; Eisersiö, Marie; Rhodin, Marie; van Weeren, René

    2015-12-30

    The use of tack (equipment such as saddles and reins) and especially of bits because of rein tension resulting in pressure in the mouth is questioned because of welfare concerns. We hypothesised that rein tension patterns in walk and trot reflect general gait kinematics, but are also determined by individual horse and rider effects. Six professional riders rode three familiar horses in walk and trot. Horses were equipped with rein tension meters logged by inertial measurement unit technique. Left and right rein tension data were synchronized with the gait. Stride split data (0-100 %) were analysed using mixed models technique to elucidate the left/right rein and stride percentage interaction, in relation to the exercises performed. In walk, rein tension was highest at hindlimb stance. Rein tension was highest in the suspension phase at trot, and lowest during the stance phase. In rising trot there was a significant difference between the two midstance phases, but not in sitting trot. When turning in trot there was a significant statistical association with the gait pattern with the tension being highest in the inside rein when the horse was on the outer fore-inner hindlimb diagonal. Substantial between-rider variation was demonstrated in walk and trot and between-horse variation in walk. Biphasic rein tensions patterns during the stride were found mainly in trot.

  6. Stern potential and Debye length measurements in dilute ionic solutions with electrostatic force microscopy

    International Nuclear Information System (INIS)

    Kumar, Bharat; Crittenden, Scott R

    2013-01-01

    We demonstrate the ability to measure Stern potential and Debye length in dilute ionic solution with atomic force microscopy. We develop an analytic expression for the second harmonic force component of the capacitive force in an ionic solution from the linearized Poisson–Boltzmann equation. This allows us to calibrate the AFM tip potential and, further, obtain the Stern potential of sample surfaces. In addition, the measured capacitive force is independent of van der Waals and double layer forces, thus providing a more accurate measure of Debye length. (paper)

  7. Stern potential and Debye length measurements in dilute ionic solutions with electrostatic force microscopy.

    Science.gov (United States)

    Kumar, Bharat; Crittenden, Scott R

    2013-11-01

    We demonstrate the ability to measure Stern potential and Debye length in dilute ionic solution with atomic force microscopy. We develop an analytic expression for the second harmonic force component of the capacitive force in an ionic solution from the linearized Poisson-Boltzmann equation. This allows us to calibrate the AFM tip potential and, further, obtain the Stern potential of sample surfaces. In addition, the measured capacitive force is independent of van der Waals and double layer forces, thus providing a more accurate measure of Debye length.

  8. Biomechanical characteristics of adults walking forward and backward in water at different stride frequencies.

    Science.gov (United States)

    Cadenas-Sánchez, Cristina; Arellano, Raúl; Taladriz, Sonia; López-Contreras, Gracia

    2016-01-01

    The aim of this study was to examine spatiotemporal characteristics and joint angles during forward and backward walking in water at low and high stride frequency. Eight healthy adults (22.1 ± 1.1 years) walked forward and backward underwater at low (50 pulses) and high frequency (80 pulses) at the xiphoid process level with arms crossed at the chest. The main differences observed were that the participants presented a greater speed (0.58 vs. 0.85 m/s) and more asymmetry of the step length (1.24 vs. 1.48) at high frequency whilst the stride and step length (0.84 vs. 0.7 m and 0.43 vs. 0.35 m, respectively) were lower compared to low frequency (P hip presented more flexion than during backward walking (ankle: 84.0 vs. 91.8º and hip: 22.8 vs. 8.0º; P hip were more flexed at low frequency than at high frequency (knee: 150.0 vs. 157.0º and hip: -12.2 vs. -14.5º; P water at different frequencies differ and contribute to a better understanding of this activity in training and rehabilitation.

  9. Utilization of coincidence criteria in absolute length measurements by optical interferometry in vacuum and air

    International Nuclear Information System (INIS)

    Schödel, R

    2015-01-01

    Traceability of length measurements to the international system of units (SI) can be realized by using optical interferometry making use of well-known frequencies of monochromatic light sources mentioned in the Mise en Pratique for the realization of the metre. At some national metrology institutes, such as Physikalisch-Technische Bundesanstalt (PTB) in Germany, the absolute length of prismatic bodies (e.g. gauge blocks) is realized by so-called gauge-block interference comparators. At PTB, a number of such imaging phase-stepping interference comparators exist, including specialized vacuum interference comparators, each equipped with three highly stabilized laser light sources. The length of a material measure is expressed as a multiple of each wavelength. The large number of integer interference orders can be extracted by the method of exact fractions in which the coincidence of the lengths resulting from the different wavelengths is utilized as a criterion. The unambiguous extraction of the integer interference orders is an essential prerequisite for correct length measurements. This paper critically discusses coincidence criteria and their validity for three modes of absolute length measurements: 1) measurements under vacuum in which the wavelengths can be identified with the vacuum wavelengths, 2) measurements under air in which the air refractive index is obtained from environmental parameters using an empirical equation, and 3) measurements under air in which the air refractive index is obtained interferometrically by utilizing a vacuum cell placed along the measurement pathway. For case 3), which corresponds to PTB’s Kösters-Comparator for long gauge blocks, the unambiguous determination of integer interference orders related to the air refractive index could be improved by about a factor of ten when an ‘overall dispersion value,’ suggested in this paper, is used as coincidence criterion. (paper)

  10. Spherical aberration compensation method for long focal-length measurement based on Talbot interferometry

    Science.gov (United States)

    Luo, Yupeng; Huang, Xiao; Bai, Jian; Du, Juan; Liu, Qun; Luo, Yujie; Luo, Jia

    2017-08-01

    Large-aperture and long focal-length lens is widely used in high energy laser system. The method based on Talbot interferometry is a reliable method to measure the focal length of such elements. By employing divergent beam and two gratings of different periods, this method could realize full-aperture measurement, higher accuracy and better repeatability. However, it does not take into account the spherical aberration of the measured lens resulting in the moiré fringes bending, which will introduce measurement error. Furthermore, in long-focal measurement with divergent beam, this error is an important factor affecting the measurement accuracy. In this paper, we propose a new spherical aberration compensation method, which could significantly reduce the measurement error. Characterized by central-symmetric scanning window, the proposed method is based on the relationship between spherical aberration and the lens aperture. Angle data of moiré fringes in each scanning window is retrieved by Fourier analysis and statistically fitted to estimate a globally optimum value for spherical-aberration-free focal length calculation. Simulation and experiment have been carried out. Compared to the previous work, the proposed method is able to reduce the relative measurement error by 50%. The effect of scanning window size and shift step length on the results is also discussed.

  11. Air method measurements of apple vessel length distributions with improved apparatus and theory

    Science.gov (United States)

    Shabtal Cohen; John Bennink; Mel Tyree

    2003-01-01

    Studies showing that rootstock dwarfing potential is related to plant hydraulic conductance led to the hypothesis that xylem properties are also related. Vessel length distribution and other properties of apple wood from a series of varieties were measured using the 'air method' in order to test this hypothesis. Apparatus was built to measure and monitor...

  12. Assessing thermally induced errors of machine tools by 3D length measurements

    NARCIS (Netherlands)

    Florussen, G.H.J.; Delbressine, F.L.M.; Schellekens, P.H.J.

    2003-01-01

    A new measurement technique is proposed for the assessment of thermally induced errors of machine tools. The basic idea is to measure changes of length by a telescopic double ball bar (TDEB) at multiple locations in the machine's workspace while the machine is thermally excited. In addition thermal

  13. The gait standard deviation, a single measure of kinematic variability.

    Science.gov (United States)

    Sangeux, Morgan; Passmore, Elyse; Graham, H Kerr; Tirosh, Oren

    2016-05-01

    Measurement of gait kinematic variability provides relevant clinical information in certain conditions affecting the neuromotor control of movement. In this article, we present a measure of overall gait kinematic variability, GaitSD, based on combination of waveforms' standard deviation. The waveform standard deviation is the common numerator in established indices of variability such as Kadaba's coefficient of multiple correlation or Winter's waveform coefficient of variation. Gait data were collected on typically developing children aged 6-17 years. Large number of strides was captured for each child, average 45 (SD: 11) for kinematics and 19 (SD: 5) for kinetics. We used a bootstrap procedure to determine the precision of GaitSD as a function of the number of strides processed. We compared the within-subject, stride-to-stride, variability with the, between-subject, variability of the normative pattern. Finally, we investigated the correlation between age and gait kinematic, kinetic and spatio-temporal variability. In typically developing children, the relative precision of GaitSD was 10% as soon as 6 strides were captured. As a comparison, spatio-temporal parameters required 30 strides to reach the same relative precision. The ratio stride-to-stride divided by normative pattern variability was smaller in kinematic variables (the smallest for pelvic tilt, 28%) than in kinetic and spatio-temporal variables (the largest for normalised stride length, 95%). GaitSD had a strong, negative correlation with age. We show that gait consistency may stabilise only at, or after, skeletal maturity. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Standing Height and its Estimation Utilizing Foot Length Measurements in Adolescents from Western Region in Kosovo

    Directory of Open Access Journals (Sweden)

    Stevo Popović

    2017-10-01

    Full Text Available The purpose of this research is to examine standing height in both Kosovan genders in the Western Region as well as its association with foot length, as an alternative to estimating standing height. A total of 664 individuals (338 male and 326 female participated in this research. The anthropometric measurements were taken according to the protocol of ISAK. The relationships between body height and foot length were determined using simple correlation coefficients at a ninety-five percent confidence interval. A comparison of means of standing height and foot length between genders was performed using a t-test. After that a linear regression analysis were carried out to examine extent to which foot length can reliably predict standing height. Results displayed that Western Kosovan male are 179.71±6.00cm tall and have a foot length of 26.73±1.20cm, while Western Kosovan female are 166.26±5.23cm tall and have a foot length of 23.66±1.06cm. The results have shown that both genders made Western-Kosovans a tall group, a little bit taller that general Kosovan population. Moreover, the foot length reliably predicts standing height in both genders; but, not reliably enough as arm span. This study also confirms the necessity for developing separate height models for each region in Kosovo as the results from Western-Kosovans don’t correspond to the general values.

  15. Measurement of Telomere Length in Colorectal Cancers for Improved Molecular Diagnosis

    Directory of Open Access Journals (Sweden)

    Eric Le Balc’h

    2017-08-01

    Full Text Available All tumors have in common to reactivate a telomere maintenance mechanism to allow for unlimited proliferation. On the other hand, genetic instability found in some tumors can result from the loss of telomeres. Here, we measured telomere length in colorectal cancers (CRCs using TRF (Telomere Restriction Fragment analysis. Telomeric DNA content was also quantified as the ratio of total telomeric (TTAGGG sequences over that of the invariable Alu sequences. In most of the 125 CRCs analyzed, there was a significant diminution in telomere length compared with that in control healthy tissue. Only 34 tumors exhibited no telomere erosion and, in some cases, a slight telomere lengthening. Telomere length did not correlate with age, gender, tumor stage, tumor localization or stage of tumor differentiation. In addition, while telomere length did not correlate with the presence of a mutation in BRAF (V-raf murine sarcoma viral oncogene homolog B, PIK3CA (phosphatidylinositol 3-kinase catalytic subunit, or MSI status, it was significantly associated with the occurrence of a mutation in KRAS. Interestingly, we found that the shorter the telomeres in healthy tissue of a patient, the larger an increase in telomere length in the tumor. Our study points to the existence of two types of CRCs based on telomere length and reveals that telomere length in healthy tissue might influence telomere maintenance mechanisms in the tumor.

  16. Measurement of the dechanneling length for high-energy negative pions

    International Nuclear Information System (INIS)

    Scandale, W.; Losito, R.; Bagli, E.; Bandiera, L.; Dalpiaz, P.; Fiorini, M.; Guidi, V.; Mazzolari, A.; Vincenzi, D.; Della Mea, G.; Vallazza, E.; Afonin, A.G.; Chesnokov, Yu.A.; Maisheev, V.A.; Yazynin, I.A.; Kovalenko, A.D.; Taratin, A.M.; Denisov, A.S.; Gavrikov, Yu.A.; Ivanov, Yu.M.

    2013-01-01

    We studied the dechanneling length of 150 GeV/cπ − interacting with a short bent silicon crystal. Dechanneling length measures the rate and the strength of incoherent interactions of channeled particles in a crystal. The mechanism of dechanneling of negatively charged particles has been elucidated through simulation and experiment. It was found that the dechanneling length for negative particles is comparable to the nuclear dechanneling length for positive charges. Indeed, dechanneling of negative particles occurs as a result of incoherent interactions with the nuclei because the trajectories of such particles always intersect atomic planes, explaining the lower channeling efficiency for such particles. Obtained results can be useful for the design of crystals for manipulating high-energy negative particle beams through channeling

  17. Measuring telomere length for the early detection of precursor lesions of esophageal squamous cell carcinoma

    International Nuclear Information System (INIS)

    Lin, Shih-Wen; Wang, Guo-Qing; Wei, Wen-Qiang; Lu, Ning; Taylor, Philip R; Qiao, You-Lin; Dawsey, Sanford M; Abnet, Christian C; Freedman, Neal D; Murphy, Gwen; Risques, Rosana; Prunkard, Donna; Rabinovitch, Peter; Pan, Qin-Jing; Roth, Mark J

    2013-01-01

    Esophageal cancer is the sixth leading cause of cancer death worldwide; current early detection screening tests are inadequate. Esophageal balloon cytology successfully retrieves exfoliated and scraped superficial esophageal epithelial cells, but cytologic reading of these cells has poor sensitivity and specificity for detecting esophageal squamous dysplasia (ESD), the precursor lesion of esophageal squamous cell carcinoma (ESCC). Measuring telomere length, a marker for chromosomal instability, may improve the utility of balloon cytology for detecting ESD and early ESCC. We examined balloon cytology specimens from 89 asymptomatic cases of ESD (37 low-grade and 52 high-grade) and 92 age- and sex-matched normal controls from an esophageal cancer early detection screening study. All subjects also underwent endoscopy and biopsy, and ESD was diagnosed histopathologically. DNA was extracted from the balloon cytology cells, and telomere length was measured by quantitative PCR. A receiver operating characteristic (ROC) curve was plotted for telomere length as a diagnostic marker for high-grade dysplasia. Telomere lengths were comparable among the low- and high-grade dysplasia cases and controls, with means of 0.96, 0.96, and 0.92, respectively. The area under the ROC curve was 0.55 for telomere length as a diagnostic marker for high-grade dysplasia. Further adjustment for subject characteristics, including sex, age, smoking, drinking, hypertension, and body mass index did not improve the use of telomere length as a marker for ESD. Telomere length of esophageal balloon cytology cells was not associated with ESCC precursor lesions. Therefore, telomere length shows little promise as an early detection marker for ESCC in esophageal balloon samples

  18. Measuring digit lengths with 3D digital stereophotogrammetry: A comparison across methods.

    Science.gov (United States)

    Gremba, Allison; Weinberg, Seth M

    2018-05-09

    We compared digital 3D stereophotogrammetry to more traditional measurement methods (direct anthropometry and 2D scanning) to capture digit lengths and ratios. The length of the second and fourth digits was measured by each method and the second-to-fourth ratio was calculated. For each digit measurement, intraobserver agreement was calculated for each of the three collection methods. Further, measurements from the three methods were compared directly to one another. Agreement statistics included the intraclass correlation coefficient (ICC) and technical error of measurement (TEM). Intraobserver agreement statistics for the digit length measurements were high for all three methods; ICC values exceeded 0.97 and TEM values were below 1 mm. For digit ratio, intraobserver agreement was also acceptable for all methods, with direct anthropometry exhibiting lower agreement (ICC = 0.87) compared to indirect methods. For the comparison across methods, the overall agreement was high for digit length measurements (ICC values ranging from 0.93 to 0.98; TEM values below 2 mm). For digit ratios, high agreement was observed between the two indirect methods (ICC = 0.93), whereas indirect methods showed lower agreement when compared to direct anthropometry (ICC < 0.75). Digit measurements and derived ratios from 3D stereophotogrammetry showed high intraobserver agreement (similar to more traditional methods) suggesting that landmarks could be placed reliably on 3D hand surface images. While digit length measurements were found to be comparable across all three methods, ratios derived from direct anthropometry tended to be higher than those calculated indirectly from 2D or 3D images. © 2018 Wiley Periodicals, Inc.

  19. Measurements of fatigue crack length at elevated temperature by D. C. electrical potential method

    International Nuclear Information System (INIS)

    Matsumoto, Masakatsu; Yamauchi, Isamu; Kodaira, Tsuneo

    1982-07-01

    The direct current (d.c.) electrical potential method was used to automatically and continuously measure the crack length in cyclic crack growth test at elevated temperature. This report describes some results concerning the calibration curves, i.e. the relation between electrical potential change and amount of crack extention, using SUS 304 and 2 1/4Cr-1Mo steels. It can be concluded that the measurements of fatigue crack length is possible even at elevated temperature as well as at room temperature with the equivalent accuracy. (author)

  20. Anthropometric measurements of foot length and shape in children 2 to 7 years of age

    OpenAIRE

    Vrdoljak, Ozren; Kujundžić Tiljak, Mirjana; Čimić, Mislav

    2017-01-01

    Background and purpose: A child’s foot changes shape and proportions during growth so that it adapts to function. The purpose of this article is to determine foot length in children aged 2-7 years as a fundamental unit for measuring the growth of the foot, with which it will be able to compare other anthropometric measures of the foot. Determination of the shape of the foot and interpretation of the growth curve of the foot in length are important for standardization of the foot.Materials and...

  1. Study on dynamic measurement of fuel pellet length during loading into cladding tube

    International Nuclear Information System (INIS)

    Zhang Kai

    1993-09-01

    Various methods are presented for measuring the pellet length in the cladding tube (zirconium tube) during the loading process of the preparation of single rod of nuclear fuel assembly. These methods are used in former Soviet Union, west European countries and China in the manufacturing of nuclear power plant element. Different methods of dynamic measurement by using mechanics, optics and electricity and their special features are analysed and discussed. The structure and measuring principle of a developed measuring device,and its measuring precision and system deviation are also introduced. Finally, the length of loaded pellets is checked with analog pellets. The results are as expected and show that the method and principle used in the measuring device are feasible. It is an ideal and advanced method for the pellet loading of single cladding tube. The principle mentioned above can also be used in other industries

  2. Foot length measurements of newborns of high and low risk pregnancies

    Directory of Open Access Journals (Sweden)

    Ana Karina Marques Salge

    Full Text Available Abstract OBJECTIVE Comparing foot length measurements of newborns in high and low risk pregnancies at a public hospital in Goiânia, GO, Brazil. METHOD A cross-sectional study carried out between April, 2013 and May, 2015, with a sample consisting of 180 newborns; 106 infants of women from high-risk pregnancies and 74 of women from low-risk pregnancies. Data were descriptively analyzed. Foot length measurement was performed using a stiff transparent plastic ruler, graduated in millimeters. The length of both feet was measured from the tip of the hallux (big toe to the end of the heel. RESULTS A statistically significant relationship was found between the foot length and newborn’s weight, between the cephalic and thoracic perimeters in the high-risk group and between the cephalic perimeter in the control group. CONCLUSION There is a need for creating cut-off points to identify newborns with intrauterine growth disorders using foot length.

  3. An Imaging System for Automated Characteristic Length Measurement of Debrisat Fragments

    Science.gov (United States)

    Moraguez, Mathew; Patankar, Kunal; Fitz-Coy, Norman; Liou, J.-C.; Sorge, Marlon; Cowardin, Heather; Opiela, John; Krisko, Paula H.

    2015-01-01

    The debris fragments generated by DebriSat's hypervelocity impact test are currently being processed and characterized through an effort of NASA and USAF. The debris characteristics will be used to update satellite breakup models. In particular, the physical dimensions of the debris fragments must be measured to provide characteristic lengths for use in these models. Calipers and commercial 3D scanners were considered as measurement options, but an automated imaging system was ultimately developed to measure debris fragments. By automating the entire process, the measurement results are made repeatable and the human factor associated with calipers and 3D scanning is eliminated. Unlike using calipers to measure, the imaging system obtains non-contact measurements to avoid damaging delicate fragments. Furthermore, this fully automated measurement system minimizes fragment handling, which reduces the potential for fragment damage during the characterization process. In addition, the imaging system reduces the time required to determine the characteristic length of the debris fragment. In this way, the imaging system can measure the tens of thousands of DebriSat fragments at a rate of about six minutes per fragment, compared to hours per fragment in NASA's current 3D scanning measurement approach. The imaging system utilizes a space carving algorithm to generate a 3D point cloud of the article being measured and a custom developed algorithm then extracts the characteristic length from the point cloud. This paper describes the measurement process, results, challenges, and future work of the imaging system used for automated characteristic length measurement of DebriSat fragments.

  4. Optimal stride frequencies in running at different speeds.

    Directory of Open Access Journals (Sweden)

    Ben T van Oeveren

    Full Text Available During running at a constant speed, the optimal stride frequency (SF can be derived from the u-shaped relationship between SF and heart rate (HR. Changing SF towards the optimum of this relationship is beneficial for energy expenditure and may positively change biomechanics of running. In the current study, the effects of speed on the optimal SF and the nature of the u-shaped relation were empirically tested using Generalized Estimating Equations. To this end, HR was recorded from twelve healthy (4 males, 8 females inexperienced runners, who completed runs at three speeds. The three speeds were 90%, 100% and 110% of self-selected speed. A self-selected SF (SFself was determined for each of the speeds prior to the speed series. The speed series started with a free-chosen SF condition, followed by five imposed SF conditions (SFself, 70, 80, 90, 100 strides·min-1 assigned in random order. The conditions lasted 3 minutes with 2.5 minutes of walking in between. SFself increased significantly (p<0.05 with speed with averages of 77, 79, 80 strides·min-1 at 2.4, 2.6, 2.9 m·s-1, respectively. As expected, the relation between SF and HR could be described by a parabolic curve for all speeds. Speed did not significantly affect the curvature, nor did it affect optimal SF. We conclude that over the speed range tested, inexperienced runners may not need to adapt their SF to running speed. However, since SFself were lower than the SFopt of 83 strides·min-1, the runners could reduce HR by increasing their SFself.

  5. Comparison of stethoscope bell and diaphragm, and of stethoscope tube length, for clinical blood pressure measurement.

    Science.gov (United States)

    Liu, Chengyu; Griffiths, Clive; Murray, Alan; Zheng, Dingchang

    2016-06-01

    This study investigated the effect of stethoscope side and tube length on auscultatory blood pressure (BP) measurement. Thirty-two healthy participants were studied. For each participant, four measurements with different combinations of stethoscope characteristics (bell or diaphragm side, standard or short tube length) were each recorded at two repeat sessions, and eight Korotkoff sound recordings were played twice on separate days to one experienced listener to determine the systolic and diastolic BPs (SBP and DBP). Analysis of variance was carried out to study the measurement repeatability between the two repeat sessions and between the two BP determinations on separate days, as well as the effects of stethoscope side and tube length. There was no significant paired difference between the repeat sessions and between the repeat determinations for both SBP and DBP (all P-values>0.10, except the repeat session for SBP using short tube and diaphragm). The key result was that there was a small but significantly higher DBP on using the bell in comparison with the diaphragm (0.66 mmHg, P=0.007), and a significantly higher SBP on using the short tube in comparison with the standard length (0.77 mmHg, P=0.008). This study shows that stethoscope characteristics have only a small, although statistically significant, influence on clinical BP measurement. Although this helps understand the measurement technique and resolves questions in the published literature, the influence is not clinically significant.

  6. Stride dynamics, gait variability and prospective falls risk in active community dwelling older women.

    Science.gov (United States)

    Paterson, Kade; Hill, Keith; Lythgo, Noel

    2011-02-01

    Measures of walking instability such as stride dynamics and gait variability have been shown to identify future fallers in older adult populations with gait limitations or mobility disorders. This study investigated whether measures of walking instability can predict future fallers (over a prospective 12 month period) in a group of healthy and active older women. Ninety-seven healthy active women aged between 55 and 90 years walked for 7 min around a continuous walking circuit. Gait data recorded by a GAITRite(®) walkway and foot-mounted accelerometers were used to calculate measures of stride dynamics and gait variability. The participant's physical function and balance were assessed. Fall incidence was monitored over the following 12 months. Inter-limb differences (p≤0.04) in stride dynamics were found for fallers (one or more falls) aged over 70 years, and multiple fallers (two or more falls) aged over 55 years, but not in non-fallers or a combined group of single and non-fallers. No group differences were found in the measures of physical function, balance or gait, including variability. Additionally, no gait variable predicted falls. Reduced coordination of inter-limb dynamics was found in active healthy older fallers and multiple fallers despite no difference in other measures of intrinsic falls risk. Evaluating inter-limb dynamics may be a clinically sensitive technique to detect early gait instability and falls risk in high functioning older adults, prior to change in other measures of physical function, balance and gait. Copyright © 2010 Elsevier B.V. All rights reserved.

  7. Stability of measures from children's interviews: the effects of time, sample length, and topic.

    Science.gov (United States)

    Heilmann, John; DeBrock, Lindsay; Riley-Tillman, T Chris

    2013-08-01

    The purpose of this study was to examine the reliability of, and sources of variability in, language measures from interviews collected from young school-age children. Two 10-min interviews were collected from 20 at-risk kindergarten children by an examiner using a standardized set of questions. Test-retest reliability coefficients were calculated for 8 language measures. Generalizability theory (G-theory) analyses were completed to document the variability introduced into the measures from the child, session, sample length, and topic. Significant and strong reliability correlation coefficients were observed for most of the language sample measures. The G-theory analyses revealed that most of the variance in the language measures was attributed to the child. Session, sample length, and topic accounted for negligible amounts of variance in most of the language measures. Measures from interviews were reliable across sessions, and the sample length and topic did not have a substantial impact on the reliability of the language measures. Implications regarding the clinical feasibility of language sample analysis for assessment and progress monitoring are discussed.

  8. Association between objectively measured physical activity, chronic stress and leukocyte telomere length.

    Science.gov (United States)

    von Känel, Roland; Bruwer, Erna J; Hamer, Mark; de Ridder, J Hans; Malan, Leoné

    2017-10-01

    Physical activity (PA) attenuates chronic stress and age-related and cardiovascular disease risks, whereby potentially slowing telomere shortening. We aimed to study the association between seven-day objectively measured habitual PA, chronic stress and leukocyte telomere length. Study participants were African (N.=96) and Caucasian (N.=107) school teachers of the Sympathetic activity and Ambulatory Blood Pressure in Africans study. All lifestyle characteristics (including PA) were objectively measured. The general health questionnaire and serum cortisol were assessed as psychological and physical measures of chronic stress. Leukocyte telomere length was measured using the quantitative real-time polymerase chain reaction. Africans had significantly shorter telomeres (Pstress or telomere length. However, more time spent with light intensity PA time was significantly and independently correlated with lower waist circumference (r=-0.21, P=0.004); in turn, greater waist circumference was significantly associated shorter telomeres (β=-0.17 [-0.30, -0.03], P=0.017). Habitual PA of different intensity was not directly associated with markers of chronic stress and leukocyte telomere length in this biethnic cohort. However, our findings suggest that light intensity PA could contribute to lowered age-related disease risk and healthy ageing by facilitating maintenance of a normal waist circumference.

  9. Assessing Children's Understanding of Length Measurement: A Focus on Three Key Concepts

    Science.gov (United States)

    Bush, Heidi

    2009-01-01

    In this article, the author presents three different tasks that can be used to assess students' understanding of the concept of length. Three important measurement concepts for students to understand are transitive reasoning, use of identical units, and iteration. In any teaching and learning process it is important to acknowledge students'…

  10. The predictive value of quantitative fibronectin testing in combination with cervical length measurement in symptomatic women

    NARCIS (Netherlands)

    Bruijn, Merel M. C.; Kamphuis, Esme I.; Hoesli, Irene M.; Martinez de Tejada, Begoña; Loccufier, Anne R.; Kühnert, Maritta; Helmer, Hanns; Franz, Marie; Porath, Martina M.; Oudijk, Martijn A.; Jacquemyn, Yves; Schulzke, Sven M.; Vetter, Grit; Hoste, Griet; Vis, Jolande Y.; Kok, Marjolein; Mol, Ben W. J.; van Baaren, Gert-Jan

    2016-01-01

    The combination of the qualitative fetal fibronectin test and cervical length measurement has a high negative predictive value for preterm birth within 7 days; however, positive prediction is poor. A new bedside quantitative fetal fibronectin test showed potential additional value over the

  11. The influence of humidity on accuracy length measurement on polymer parts

    DEFF Research Database (Denmark)

    Madruga, Daniel González; Alexiou, A.; Dalla Costa, Giuseppe

    2016-01-01

    The work deals with an experimental study of the influence of humidity on accurate length measurements on ABS parts. Polymer parts absorb water from the ambient until they reach hygroscopic equilibrium. Water content causes an expansion of the polymer part. The relationship between the water cont...

  12. Measuring retinal blood flow in rats using Doppler optical coherence tomography without knowing eyeball axial length

    International Nuclear Information System (INIS)

    Liu, Wenzhong; Yi, Ji; Chen, Siyu; Jiao, Shuliang; Zhang, Hao F.

    2015-01-01

    Purpose: Doppler optical coherence tomography (OCT) is widely used for measuring retinal blood flow. Existing Doppler OCT methods require the eyeball axial length, in which empirical values are usually used. However, variations in the axial length can create a bias unaccounted for in the retinal blood flow measurement. The authors plan to develop a Doppler OCT method that can measure the total retinal blood flow rate without requiring the eyeball axial length. Methods: The authors measured the retinal blood flow rate using a dual-ring scanning protocol. The small and large scanning rings entered the eye at different incident angles (small ring: 4°; large ring: 6°), focused on different locations on the retina, and detected the projected velocities/phase shifts along the probing beams. The authors calculated the ratio of the projected velocities between the two rings, and then used this ratio to estimate absolute flow velocity. The authors tested this method in both Intralipid phantoms and in vivo rats. Results: In the Intralipid flow phantom experiments, the preset and measured flow rates were consistent with the coefficient of determination as 0.97. Linear fitting between preset and measured flow rates determined the fitting slope as 1.07 and the intercept as −0.28. In in vivo rat experiments, the measured average total retinal blood flow was 7.02 ± 0.31μl/min among four wild-type rats. The authors’ measured flow rates were consistent with results in the literature. Conclusions: By using a dual-ring scanning protocol with carefully controlled incident angle difference between the two scanning rings in Doppler OCT, the authors demonstrated that it is feasible to measure the absolute retinal blood flow without knowing the eyeball axial length

  13. Measuring retinal blood flow in rats using Doppler optical coherence tomography without knowing eyeball axial length.

    Science.gov (United States)

    Liu, Wenzhong; Yi, Ji; Chen, Siyu; Jiao, Shuliang; Zhang, Hao F

    2015-09-01

    Doppler optical coherence tomography (OCT) is widely used for measuring retinal blood flow. Existing Doppler OCT methods require the eyeball axial length, in which empirical values are usually used. However, variations in the axial length can create a bias unaccounted for in the retinal blood flow measurement. The authors plan to develop a Doppler OCT method that can measure the total retinal blood flow rate without requiring the eyeball axial length. The authors measured the retinal blood flow rate using a dual-ring scanning protocol. The small and large scanning rings entered the eye at different incident angles (small ring: 4°; large ring: 6°), focused on different locations on the retina, and detected the projected velocities/phase shifts along the probing beams. The authors calculated the ratio of the projected velocities between the two rings, and then used this ratio to estimate absolute flow velocity. The authors tested this method in both Intralipid phantoms and in vivo rats. In the Intralipid flow phantom experiments, the preset and measured flow rates were consistent with the coefficient of determination as 0.97. Linear fitting between preset and measured flow rates determined the fitting slope as 1.07 and the intercept as -0.28. In in vivo rat experiments, the measured average total retinal blood flow was 7.02 ± 0.31 μl/min among four wild-type rats. The authors' measured flow rates were consistent with results in the literature. By using a dual-ring scanning protocol with carefully controlled incident angle difference between the two scanning rings in Doppler OCT, the authors demonstrated that it is feasible to measure the absolute retinal blood flow without knowing the eyeball axial length.

  14. Measuring retinal blood flow in rats using Doppler optical coherence tomography without knowing eyeball axial length

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Wenzhong; Yi, Ji; Chen, Siyu [Department of Biomedical Engineering, Northwestern University, Evanston, Illinois 60208 (United States); Jiao, Shuliang [Department of Biomedical Engineering, Florida International University, Miami, Florida 33174 (United States); Zhang, Hao F., E-mail: hfzhang@northwestern.edu [Department of Biomedical Engineering, Northwestern University, Evanston, Illinois 60208 and Department of Ophthalmology, Northwestern University, Chicago, Illinois 60611 (United States)

    2015-09-15

    Purpose: Doppler optical coherence tomography (OCT) is widely used for measuring retinal blood flow. Existing Doppler OCT methods require the eyeball axial length, in which empirical values are usually used. However, variations in the axial length can create a bias unaccounted for in the retinal blood flow measurement. The authors plan to develop a Doppler OCT method that can measure the total retinal blood flow rate without requiring the eyeball axial length. Methods: The authors measured the retinal blood flow rate using a dual-ring scanning protocol. The small and large scanning rings entered the eye at different incident angles (small ring: 4°; large ring: 6°), focused on different locations on the retina, and detected the projected velocities/phase shifts along the probing beams. The authors calculated the ratio of the projected velocities between the two rings, and then used this ratio to estimate absolute flow velocity. The authors tested this method in both Intralipid phantoms and in vivo rats. Results: In the Intralipid flow phantom experiments, the preset and measured flow rates were consistent with the coefficient of determination as 0.97. Linear fitting between preset and measured flow rates determined the fitting slope as 1.07 and the intercept as −0.28. In in vivo rat experiments, the measured average total retinal blood flow was 7.02 ± 0.31μl/min among four wild-type rats. The authors’ measured flow rates were consistent with results in the literature. Conclusions: By using a dual-ring scanning protocol with carefully controlled incident angle difference between the two scanning rings in Doppler OCT, the authors demonstrated that it is feasible to measure the absolute retinal blood flow without knowing the eyeball axial length.

  15. Concordance and interchangeability of biometric measurements of ocular axial length in patients awaiting cataract surgery.

    Science.gov (United States)

    Martín-Serrano, María José; Roman-Ortiz, Carmen; Villa-Sáez, M Luz; Labrador-Castellanos, M Purificación; Blanco-Carrasco, Rosario; Lozano-Ballesteros, Felicidad; Pedraza-Martín, Carmen; José-Herrero, M Teresa San; López-Ropero, Ana M; Tenías Burillo, José María

    2014-01-01

    To estimate in patients awaiting cataract surgery the concordance and interchangeability of axial eye length measurements performed with the aid of various biometric methods (optical or ultrasonic) by different operators (nurses) at different times during the period prior to surgery. We selected 182 consecutive eyes from 91 patients.Ocular axial length was measured with the aid of 2 methods (IOLMaster® and Ocuscan®) by 9 randomly allocated technicians at 2 different times during the waiting period. The concordance between measurements was evaluated by means of the intraclass correlation coefficient (ICC); the interchangeability of the results was assessed with Bland Altman plots and Passing and Bablok regression. The measurements were consistent between biometric methods (ICC 0.975, 95% confidence interval [CI] 0.968 to 0.980) and measurement dates (ICC 0.996, 95% CI 0.995 to 0.997). Interobserver agreement was more heterogeneous (ICC range 0.844 to 0.998). No systematic errors were observed among the various biometric methods and measurement dates. Because measurement of axial length in phakic patients may be technician-dependent, the technician's experience should be noted in the protocols of ophthalmology services.

  16. Measuring the attenuation length of water in the CHIPS-M water Cherenkov detector

    Energy Technology Data Exchange (ETDEWEB)

    Amat, F.; Bizouard, P. [Aix Marseille University Saint-Jerome, 13013 Marseille (France); Bryant, J. [Department of Physics and Astronomy, UCL, Gower St, London WC1E 6BT (United Kingdom); Carroll, T.J.; Rijck, S. De [Department of Physics, University of Texas at Austin, Austin, TX 78712 (United States); Germani, S. [Department of Physics and Astronomy, UCL, Gower St, London WC1E 6BT (United Kingdom); Joyce, T. [School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States); Kriesten, B. [Department of Physics, College of William & Mary, Williamsburg, VA 23187 (United States); Marshak, M.; Meier, J. [School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States); Nelson, J.K. [Department of Physics, College of William & Mary, Williamsburg, VA 23187 (United States); Perch, A.J.; Pfützner, M.M. [Department of Physics and Astronomy, UCL, Gower St, London WC1E 6BT (United Kingdom); Salazar, R. [Department of Physics, University of Texas at Austin, Austin, TX 78712 (United States); Thomas, J., E-mail: jennifer.thomas@ucl.ac.uk [Department of Physics and Astronomy, UCL, Gower St, London WC1E 6BT (United Kingdom); Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Trokan-Tenorio, J. [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Vahle, P. [Department of Physics, College of William & Mary, Williamsburg, VA 23187 (United States); Wade, R. [Avenir Consulting, Abingdon, Oxfordshire (United Kingdom); Wendt, C. [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Whitehead, L.H. [Department of Physics and Astronomy, UCL, Gower St, London WC1E 6BT (United Kingdom); and others

    2017-02-01

    The water at the proposed site of the CHIPS water Cherenkov detector has been studied to measure its attenuation length for Cherenkov light as a function of filtering time. A scaled model of the CHIPS detector filled with water from the Wentworth 2W pit, proposed site of the CHIPS deployment, in conjunction with a 3.2 m vertical column filled with this water, was used to study the transmission of 405 nm laser light. Results consistent with attenuation lengths of up to 100 m were observed for this wavelength with filtration and UV sterilization alone.

  17. Measurement of the diffusion length of thermal neutrons in the beryllium oxide

    International Nuclear Information System (INIS)

    Koechlin, J.C.; Martelly, J.; Duggal, V.P.

    1955-01-01

    The diffusion length of thermal neutrons in the beryllium oxide has been obtained while studying the spatial distribution of the neutrons in a massive parallelepiped of this matter placed before the thermal column of the reactor core of Saclay. The mean density of the beryllium oxide (BeO) is 2,95 gr/cm 3 , the mean density of the massif is 2,92 gr/cm 3 . The value of the diffusion length, deducted of the done measures, is: L = 32,7 ± 0,5 cm (likely gap). Some remarks are formulated about the influence of the spectral distribution of the neutrons flux used. (authors) [fr

  18. The measurement of the optical cavity length for the infrared free electron laser

    International Nuclear Information System (INIS)

    Curtis, C.J.; Dahlberg, J.C.; Oren, W.A.; Tremblay, K.J.

    1999-01-01

    One of the final tasks involved in the alignment of the newly constructed Free Electron Laser at the Thomas Jefferson National Accelerator Facility was to accurately measure the length between two mirrors which make up the optical cavity. This presentation examines the survey techniques and equipment assembled in order to complete these measurements, together with the possible sources of error, and the accuracy achieved. (authors)

  19. Measurement of metal/carbon nanotube contact resistance by adjusting contact length using laser ablation

    Energy Technology Data Exchange (ETDEWEB)

    Lan Chun; Srisungsitthisunti, Pornsak; Amama, Placidus B; Fisher, Timothy S; Xu Xianfan; Reifenberger, Ronald G [Birck Nanotechnology Center, Purdue University, West Lafayette, IN 47907 (United States)], E-mail: lan0@physics.purdue.edu

    2008-03-26

    A technique of measuring contact resistance between an individual nanotube and a deposited metallic film is described. Using laser ablation to sequentially shorten the contact length between a nanotube and the evaporated metallic film, the linear resistivity of the nanotube as well as the specific contact resistivity between the nanotube and metallic film can be determined. This technique can be generally used to measure the specific contact resistance that develops between a metallic film and a variety of different nanowires and nanotubes.

  20. [Measurement of screw length through drilling technique in osteosynthesis of the proximal humerus fractures].

    Science.gov (United States)

    Avcı, Cem Coşkun; Gülabi, Deniz; Sağlam, Necdet; Kurtulmuş, Tuhan; Saka, Gürsel

    2013-01-01

    This study aims to investigate the efficacy of screw length measurement through drilling technique on the reduction of intraarticular screw penetration and fluoroscopy time in osteosynthesis of proximal humerus fractures. Between January 2008 and June 2012, 98 patients (34 males, 64 females; mean age 64.4 years; range 35 to 81 years) who underwent osteosynthesis using locking anatomical proximal humerus plates (PHILOS) in our clinic with the diagnosis of Neer type 2, 3 or 4 were included. Two different surgical techniques were used to measure proximal screw length in the plate and patients were divided into two groups based on the technique used. In group 1, screw length was determined by a 3 mm blunt tipped Kirschner wire without fluoroscopic control. In group 2, bilateral fluoroscopic images for each screw at least were obtained. Intraarticular screw penetration was detected in five patients (10.6%) in group 1, and in 19 patients (37.3%) in group 2. The mean fluoroscopic imaging time was 10.6 seconds in group 1 and 24.8 seconds in group 2, indicating a statistically significant difference. Screw length measurement through the drilling technique significantly reduces the intraarticular screw penetration and fluoroscopy time in osteosynthesis of proximal humerus fractures using PHILOS plates.

  1. Photon path length distributions for cloudy skies – oxygen A-Band measurements and model calculations

    Directory of Open Access Journals (Sweden)

    O. Funk

    2003-03-01

    Full Text Available This paper addresses the statistics underlying cloudy sky radiative transfer (RT by inspection of the distribution of the path lengths of solar photons. Recent studies indicate that this approach is promising, since it might reveal characteristics about the diffusion process underlying atmospheric radiative transfer (Pfeilsticker, 1999. Moreover, it uses an observable that is directly related to the atmospheric absorption and, therefore, of climatic relevance. However, these studies are based largely on the accuracy of the measurement of the photon path length distribution (PPD. This paper presents a refined analysis method based on high resolution spectroscopy of the oxygen A-band. The method is validated by Monte Carlo simulation atmospheric spectra. Additionally, a new method to measure the effective optical thickness of cloud layers, based on fitting the measured differential transmissions with a 1-dimensional (discrete ordinate RT model, is presented. These methods are applied to measurements conducted during the cloud radar inter-comparison campaign CLARE’98, which supplied detailed cloud structure information, required for the further analysis. For some exemplary cases, measured path length distributions and optical thicknesses are presented and backed by detailed RT model calculations. For all cases, reasonable PPDs can be retrieved and the effects of the vertical cloud structure are found. The inferred cloud optical thicknesses are in agreement with liquid water path measurements. Key words. Meteorology and atmospheric dynamics (radiative processes; instruments and techniques

  2. Photon path length distributions for cloudy skies – oxygen A-Band measurements and model calculations

    Directory of Open Access Journals (Sweden)

    O. Funk

    Full Text Available This paper addresses the statistics underlying cloudy sky radiative transfer (RT by inspection of the distribution of the path lengths of solar photons. Recent studies indicate that this approach is promising, since it might reveal characteristics about the diffusion process underlying atmospheric radiative transfer (Pfeilsticker, 1999. Moreover, it uses an observable that is directly related to the atmospheric absorption and, therefore, of climatic relevance. However, these studies are based largely on the accuracy of the measurement of the photon path length distribution (PPD. This paper presents a refined analysis method based on high resolution spectroscopy of the oxygen A-band. The method is validated by Monte Carlo simulation atmospheric spectra. Additionally, a new method to measure the effective optical thickness of cloud layers, based on fitting the measured differential transmissions with a 1-dimensional (discrete ordinate RT model, is presented. These methods are applied to measurements conducted during the cloud radar inter-comparison campaign CLARE’98, which supplied detailed cloud structure information, required for the further analysis. For some exemplary cases, measured path length distributions and optical thicknesses are presented and backed by detailed RT model calculations. For all cases, reasonable PPDs can be retrieved and the effects of the vertical cloud structure are found. The inferred cloud optical thicknesses are in agreement with liquid water path measurements.

    Key words. Meteorology and atmospheric dynamics (radiative processes; instruments and techniques

  3. [Methods of measuring telomere length and telomerase activity--practice and problems].

    Science.gov (United States)

    Saito, Y; Suda, T; Hatakeyama, K

    1998-05-01

    The development of a highly sensitive method for detection of telomerase activity, telomeric repeat amplification protocol (TRAP), has provided knowledge on telomerase activity in normal and cancer tissues. Subsequent several modifications have been achieved, including an introduction of the internal standard and hybridization protection technique that leads to simplicity and improvement of reproducibility and linearity of this method, and application of TRAP to in situ analysis to identify the cells responsible for telomerase activity. As for measurement of telomere length, fluorescence in situ hybridization technique appeared to give an information of telomere length on an individual chromosome in contrast to analysis of terminal restriction fragment, a conventional method which can express mean telomere length of all chromosomes. Further methodological improvement in this field is ongoing and showing a new sight on cell mortality and immortality.

  4. Cervical Length & Leading Placental Edge to Internal OS Measurements - TA vs TV

    DEFF Research Database (Denmark)

    Westerway, Sue Campbell; Pedersen, Lars Henning; Hyett, Jon

    Brief Description of the Purpose of the Study: To compare cervical length/leading placental edge from the internal cervical os measurements obtained by both transabdominal (TA) and transvaginal (TV) approach and to assess intra / inter-observer variation for these measurements. Methods: Cross...... sectional study of 374 consecutive pregnancies with gestation 12 weeks to term. The cervical length was estimated as the distance from internal to external os, and the placenta / cervix distance as the leading placental edge to internal cervical os. Bland-Altman plots were used to evaluate the two methods....... Importance of the Conclusions: TA estimates of cervix and placental edge position did not reflect the estimates obtained by TV assessment. As both measures are important markers of pregnancy outcome and management, the transabdominal method in the present form is insuffi- cient in clinical management....

  5. Microscopic optical path length difference and polarization measurement system for cell analysis

    Science.gov (United States)

    Satake, H.; Ikeda, K.; Kowa, H.; Hoshiba, T.; Watanabe, E.

    2018-03-01

    In recent years, noninvasive, nonstaining, and nondestructive quantitative cell measurement techniques have become increasingly important in the medical field. These cell measurement techniques enable the quantitative analysis of living cells, and are therefore applied to various cell identification processes, such as those determining the passage number limit during cell culturing in regenerative medicine. To enable cell measurement, we developed a quantitative microscopic phase imaging system based on a Mach-Zehnder interferometer that measures the optical path length difference distribution without phase unwrapping using optical phase locking. The applicability of our phase imaging system was demonstrated by successful identification of breast cancer cells amongst normal cells. However, the cell identification method using this phase imaging system exhibited a false identification rate of approximately 7%. In this study, we implemented a polarimetric imaging system by introducing a polarimetric module to one arm of the Mach-Zehnder interferometer of our conventional phase imaging system. This module was comprised of a quarter wave plate and a rotational polarizer on the illumination side of the sample, and a linear polarizer on the optical detector side. In addition, we developed correction methods for the measurement errors of the optical path length and birefringence phase differences that arose through the influence of elements other than cells, such as the Petri dish. As the Petri dish holding the fluid specimens was transparent, it did not affect the amplitude information; however, the optical path length and birefringence phase differences were affected. Therefore, we proposed correction of the optical path length and birefringence phase for the influence of elements other than cells, as a prerequisite for obtaining highly precise phase and polarimetric images.

  6. The value of Sonographic measurement of cervical length and fetal fibronectin testing in predicting preterm delivery

    Directory of Open Access Journals (Sweden)

    Zeki Salar

    2007-03-01

    Full Text Available OBJECTIVE: The aim of this study was to determine whether the combination of both fetal fibronectin and sonographic measurement of cervical length in women with preterm labor provides a better prediction than the individual tests alone.\tMETHODS: We examined 40 women with singleton pregnancies presenting at 24–35 (median 31 weeks of gestation with regular and painful uterine contractions, intact membranes and cervical dilatation of less than 3 cm. On admission to the hospital, fetal fibronectin positivity in cervicovaginal secretions was determined and transvaginal sonographic measurement of cervical length was carried out. The primary outcome measure was delivery within 14 days of presentation.\tRESULTS: Total of 40 eligible women at a mean gestational age of 28,3±4,8 weeks were enrolled from a population of 196 subjects screened. The overall prevalence of preterm delivery CONCLUSIONS: Combined the assessment of fetal fibronectin in cervico-vaginal secretions and the sonographic cervical length measurement improve the prediction of preterm delivery within 14 days in women with threatened preterm labor

  7. Non-dispersive method for measuring longitudinal neutron coherence length using high frequency cold neutron pulser

    International Nuclear Information System (INIS)

    Kawai, T.; Tasaki, S.; Ebisawa, T.; Hino, M.; Yamazaki, D.; Achiwa, N.

    1999-01-01

    Complete text of publication follows. A non-dispersive method is proposed for measuring the longitudinal coherence length of a neutron using a high frequency cold neutron pulser (hf-CNP) placed between two multilayer spin splitters (MSS) which composes the cold neutron spin interferometer. Two spin eigenstates of a neutron polarized x-y plane are split non-dispersively and longitudinally in time by the hf-CNP which could reflect two components alternatively in time. The reduction of the visibility of interference fringes after being superposed by the second MSS is measured as a function of the frequency of the pulser by TOF method. From the zero visibility point obtained by extrapolation one could obtain the longitudinal coherence length of the neutron. (author)

  8. Selecting Therapeutic Targets in Inflammatory Bowel Disease (STRIDE)

    DEFF Research Database (Denmark)

    Peyrin-Biroulet, L; Sandborn, W; Sands, B E

    2015-01-01

    OBJECTIVES: The Selecting Therapeutic Targets in Inflammatory Bowel Disease (STRIDE) program was initiated by the International Organization for the Study of Inflammatory Bowel Diseases (IOIBD). It examined potential treatment targets for inflammatory bowel disease (IBD) to be used for a "treat-t...... target. CONCLUSIONS: Evidence- and consensus-based recommendations for selecting the goals for treat-to-target strategies in patients with IBD are made available. Prospective studies are needed to determine how these targets will change disease course and patients' quality of life....

  9. Determination of ππ scattering lengths from measurement of π+π- atom lifetime

    International Nuclear Information System (INIS)

    Adeva, B.; Afanasyev, L.; Benayoun, M.; Benelli, A.; Berka, Z.; Brekhovskikh, V.; Caragheorgheopol, G.; Cechak, T.; Chiba, M.; Chliapnikov, P.V.; Ciocarlan, C.; Constantinescu, S.; Costantini, S.; Curceanu, C.; Doskarova, P.; Dreossi, D.; Drijard, D.; Dudarev, A.; Ferro-Luzzi, M.; Fungueirino Pazos, J.L.

    2011-01-01

    The DIRAC experiment at CERN has achieved a sizeable production of π + π - atoms and has significantly improved the precision on its lifetime determination. From a sample of 21 227 atomic pairs, a 4% measurement of the S-wave ππ scattering length difference |a 0 -a 2 |=(0.2533 -0.0078 +0.0080 | stat +0.0078 -0.0073 | syst )M π + -1 has been attained, providing an important test of Chiral Perturbation Theory.

  10. The accuracy of the radiographic method in root canal length measurement

    International Nuclear Information System (INIS)

    Jo, Eun Young; Park, Chang Seo

    1998-01-01

    For the successful endodontic treatment, root canal should be cleaned thoroughly by accurate mechanical and chemical canal preparation and sealed completely with canal filling material without damaging the periapical tissues. The accuracy of the root canal length measurement is a prerequisite for the success of the endodontic treatment, and the root canal length is often determined by the standard periapical radiographs and digital tactile sense. In this study, the accuracy and the clinical usefulness of Digora, an intraoral digital imaging processor and the conventional standard radiographs were compared by measuring the length from the top of the file to the root apex. 30 single rooted premolars were invested in a uniformly sized blocks and No.25 K-file was inserted into and fixed in each canal. Each block was placed in equal distance and position to satisfy the principle of the bisecting angle and paralleling techniques and Digora system's image and standard periapical radiographs were taken. Each radiograph was examined by 3 different observers by measuring the length from top of the file to the root apex and each data was compared and analyzed. The results were as follows; 1. In the bisecting angle technique, the average difference between the Digora system and standard periapical radiograph was 0.002 mm and the standard deviation was 0.341 mm which showed no statistically significant difference between the two systems (p>0.05). Also, in the paralleling technique, the average difference between these two system was 0.007 mm and the standard deviation was 0.323 mm which showed no statistically significant difference between the two systems (p>0.05). 2. In Digora system, the average difference between the bisecting angle and paralleling technique was -0.336 mm and the standard deviation was 0.472 mm which showed a statistically significant difference between the two techniques (p 0.05). In conclusion, the determination of the root canal length by using the

  11. Measurements of electric charge and screening length of microparticles in a plasma sheath

    International Nuclear Information System (INIS)

    Nakamura, Y.; Ishihara, O.

    2009-01-01

    An experiment is described in which microparticles are levitated within a rf sheath above a conducting plate in argon plasma. The microparticles forming a two-dimensional crystal structure are considered to possess Debye screening Coulomb potential φ(r)=(Q/4πε 0 r)exp(-r/λ), where Q is the electric charge, r is distance, and λ is the screening length. When the crystal structure is slanted with an angle θ, a particle experiences a force Mg sin θ, where M is the mass of the particle and g is acceleration due to gravity, which must be equal to the Debye screened Coulomb force from other particles. By changing θ, relations for λ(Q) are measured. The screening length λ and Q are determined uniquely from the crossing points of several relations. The electric charge Q is also estimated from a floating potential measured with a probe. The measured λ is nearly equal to an ion Debye length.

  12. Realization of the Zone Length Measurement during Zone Refining Process via Implementation of an Infrared Camera

    Directory of Open Access Journals (Sweden)

    Danilo C. Curtolo

    2018-05-01

    Full Text Available Zone refining, as the currently most common industrial process to attain ultrapure metals, is influenced by a variety of factors. One of these parameters, the so-called “zone length”, affects not only the ultimate concentration distribution of impurities, but also the rate at which this distribution is approached. This important parameter has however neither been investigated experimentally, nor ever varied for the purpose of optimization. This lack of detections may be due to the difficult temperature measurement of a moving molten area in a vacuum system, of which the zone refining methodology is comprised. Up to now, numerical simulation as a combination of complex mathematical calculations, as well as many assumptions has been the only way to reveal it. This paper aims to propose an experimental method to accurately measure the molten zone length and to extract helpful information on the thermal gradient, temperature profile and real growth rate in the zone refining of an exemplary metal, in this case aluminum. This thermographic method is based on the measurement of the molten surface temperature via an infrared camera, as well as further data analysis through the mathematical software MATLAB. The obtained results show great correlation with the visual observations of zone length and provide helpful information to determine the thermal gradient and real growth rate during the whole process. The investigations in this paper approved the application of an infrared camera for this purpose as a promising technique to automatically control the zone length during a zone refining process.

  13. Effect of length of measurement period on accuracy of predicted annual heating energy consumption of buildings

    International Nuclear Information System (INIS)

    Cho, Sung-Hwan; Kim, Won-Tae; Tae, Choon-Soeb; Zaheeruddin, M.

    2004-01-01

    This study examined the temperature dependent regression models of energy consumption as a function of the length of the measurement period. The methodology applied was to construct linear regression models of daily energy consumption from 1 day to 3 months data sets and compare the annual heating energy consumption predicted by these models with actual annual heating energy consumption. A commercial building in Daejon was selected, and the energy consumption was measured over a heating season. The results from the investigation show that the predicted energy consumption based on 1 day of measurements to build the regression model could lead to errors of 100% or more. The prediction error decreased to 30% when 1 week of data was used to build the regression model. Likewise, the regression model based on 3 months of measured data predicted the annual energy consumption within 6% of the measured energy consumption. These analyses show that the length of the measurement period has a significant impact on the accuracy of the predicted annual energy consumption of buildings

  14. Scattering length measurements from radiative pion capture and neutron-deuteron breakup

    International Nuclear Information System (INIS)

    Gibson, B.F.; Tornow, W.; Carman, T.S.

    1997-07-01

    The neutron-neutron and neutron-proton 1 S 0 scattering lengths a nn and a np , respectively, were determined simultaneously from the neutron-deuteron breakup reaction. Their comparison with the recommended values obtained from two body reactions gives a measure of the importance of three-nucleon force effects in the three-nucleon continuum. In order to check on the result obtained for a nn from the two-body π - -d capture reaction, a new measurement was performed at LANL. Preliminary results of the three experiments are given

  15. Scattering length measurements from radiative pion capture and neutron-deuteron breakup

    Energy Technology Data Exchange (ETDEWEB)

    Tornow, W.; Chen, Q. [Duke Univ., Durham, NC (United States). Dept. of Physics; Carman, T.S. [Lawrence Livermore National Lab., CA (United States). Program for Climate Model Diagnosis and Intercomparison] [and others

    1998-03-02

    The neutron-neutron and neutron-proton {sup 1}S{sub 0} scattering lengths a{sub nn} and a{sub np}, respectively, were determined simultaneously from the neutron-deuteron breakup reaction. Their comparison with the recommended values obtained from ``two-body`` reactions gives a measure of the importance of three-nucleon force effects in the three-nucleon continuum. In order to check on the result obtained for a{sub nn} from the ``two-body`` {pi}{sup -}-d capture reaction, a new measurement was performed at LANL. Preliminary results of the three experiments are given. (orig.). 5 refs.

  16. Radial correlation length measurements on ASDEX Upgrade using correlation Doppler reflectometry

    International Nuclear Information System (INIS)

    Schirmer, J; Conway, G D; Holzhauer, E; Suttrop, W; Zohm, H

    2007-01-01

    The technique of correlation Doppler reflectometry for providing radial correlation length L r measurements is explored in this paper. Experimental L r measurements are obtained using the recently installed dual channel Doppler reflectometer system on ASDEX Upgrade. The experimental measurements agree well with theory and with L r measured on other fusion devices using different diagnostic techniques. A strong link between L r and plasma confinement could be observed. From the L- to the H-mode, an increase in the absolute value of E r shear was detected at the same plasma edge region where a decrease in L r was measured. This observation is in agreement with theoretical models which predict that an increase in the absolute shear suppresses turbulent fluctuations in the plasma, leading to a reduction in L r . Furthermore, L r decreases from the plasma core to the edge and decreases with increasing plasma triangularity δ. The experimental results have been extensively modelled using a 2-dimensional finite difference time domain code. The simulations confirm that Doppler reflectometry provides robust radial correlation lengths of the turbulence with high resolution and suggests that L r is independent of the turbulence wavenumber k p erpendicular and its fluctuation level

  17. Reliability of length measurements collected by community nurses and health volunteers in rural growth monitoring and promotion services.

    Science.gov (United States)

    Laar, Matilda E; Marquis, Grace S; Lartey, Anna; Gray-Donald, Katherine

    2018-02-17

    Length measurements are important in growth, monitoring and promotion (GMP) for the surveillance of a child's weight-for-length and length-for-age. These two indices provide an indication of a child's risk of becoming wasted or stunted, and are more informative about a child's growth than the widely used weight-for-age index (underweight). Although the introduction of length measurements in GMP is recommended by the World Health Organization, concerns about the reliability of length measurements collected in rural outreach settings have been expressed by stakeholders. Our aim was to describe the reliability and challenges associated with community health personnel measuring length for rural outreach GMP activities. Two reliability studies (A and B), using 10 children less than 24 months each, were conducted in the GMP services of a rural district in Ghana. Fifteen nurses and 15 health volunteers (HV) with no prior experience in length measurements were trained. Intra- and inter-observer technical error of measurement (TEM), average bias from expert anthropometrist, and coefficient of reliability (R) of length measurements were assessed and compared across sessions. Observations and interviews were used to understand the ability and experiences of health personnel with measuring length at outreach GMP. Inter-observer TEM was larger than intra-observer TEM for both nurses and HV at both sessions and was unacceptably (compared to error standards) high in both groups at both time points. Average biases from expert's measurements were within acceptable limits, however, both groups tended to underestimate length measurements. The R for lengths collected by nurses (92.3%) was higher at session B compared to that of HV (87.5%). Length measurements taken by nurses and HV, and those taken by an experienced anthropometrist at GMP sessions were of moderate agreement (kappa = 0.53, p reliability of length measurements improved after two refresher trainings for nurses but

  18. Photoluminescence decay lifetime measurements of hemicyanine derivatives of different alkyl chain lengths

    International Nuclear Information System (INIS)

    Shim, Taekyu; Lee, Myounghee; Kim, Sungho; Sung, Jaeho; Rhee, Bum Ku; Kim, Doseok; Kim, Hyunsung; Yoon, Kyung Byung

    2004-01-01

    The fluorescence upconversion setup for the detection of photoluminescence (PL) decay lifetime with subpicosecond time resolution was constructed, and the photoluminescence phenomena of several hemicyanine dyes with alkyl chains of different chain lengths tethered to the N atom of the pyridine moiety (HC-n, n=6, 15, 22) in methanol were investigated. The average decay lifetimes of the solutions determined from the measured data by multi-order exponential decay curve fitting were ∼27 ps at the PL peak wavelength. It was found that the PL decay properties did not depend on the alkyl chain length in the molecule, implying that the twist of the alkylpyridinium ring of the molecule is not possible as a nonfluorescing relaxation pathway. The time-dependent PL spectra constructed from the PL lifetime data showed the dynamic Stokes shift of ∼1000 cm -1

  19. Single-Camera-Based Method for Step Length Symmetry Measurement in Unconstrained Elderly Home Monitoring.

    Science.gov (United States)

    Cai, Xi; Han, Guang; Song, Xin; Wang, Jinkuan

    2017-11-01

    single-camera-based gait monitoring is unobtrusive, inexpensive, and easy-to-use to monitor daily gait of seniors in their homes. However, most studies require subjects to walk perpendicularly to camera's optical axis or along some specified routes, which limits its application in elderly home monitoring. To build unconstrained monitoring environments, we propose a method to measure step length symmetry ratio (a useful gait parameter representing gait symmetry without significant relationship with age) from unconstrained straight walking using a single camera, without strict restrictions on walking directions or routes. according to projective geometry theory, we first develop a calculation formula of step length ratio for the case of unconstrained straight-line walking. Then, to adapt to general cases, we propose to modify noncollinear footprints, and accordingly provide general procedure for step length ratio extraction from unconstrained straight walking. Our method achieves a mean absolute percentage error (MAPE) of 1.9547% for 15 subjects' normal and abnormal side-view gaits, and also obtains satisfactory MAPEs for non-side-view gaits (2.4026% for 45°-view gaits and 3.9721% for 30°-view gaits). The performance is much better than a well-established monocular gait measurement system suitable only for side-view gaits with a MAPE of 3.5538%. Independently of walking directions, our method can accurately estimate step length ratios from unconstrained straight walking. This demonstrates our method is applicable for elders' daily gait monitoring to provide valuable information for elderly health care, such as abnormal gait recognition, fall risk assessment, etc. single-camera-based gait monitoring is unobtrusive, inexpensive, and easy-to-use to monitor daily gait of seniors in their homes. However, most studies require subjects to walk perpendicularly to camera's optical axis or along some specified routes, which limits its application in elderly home monitoring

  20. Round-Trip System Available to Measure Path Length Variation in Korea VLBI System for Geodesy

    Science.gov (United States)

    Oh, Hongjong; Kondo, Tetsuro; Lee, Jinoo; Kim, Tuhwan; Kim, Myungho; Kim, Suchul; Park, Jinsik; Ju, Hyunhee

    2010-01-01

    The construction project of Korea Geodetic VLBI officially started in October 2008. The construction of all systems will be completed by the end of 2011. The project was named Korea VLBI system for Geodesy (KVG), and its main purpose is to maintain the Korea Geodetic Datum. In case of the KVG system, an observation room with an H-maser frequency standard is located in a building separated from the antenna by several tens of meters. Therefore KVG system will adopt a so-called round-trip system to transmit reference signals to the antenna with reduction of the effect of path length variations. KVG s round-trip system is designed not only to use either metal or optical fiber cables, but also to measure path length variations directly. We present this unique round trip system for KVG.

  1. A comparative analysis of spectral exponent estimation techniques for 1/fβ processes with applications to the analysis of stride interval time series

    Science.gov (United States)

    Schaefer, Alexander; Brach, Jennifer S.; Perera, Subashan; Sejdić, Ervin

    2013-01-01

    Background The time evolution and complex interactions of many nonlinear systems, such as in the human body, result in fractal types of parameter outcomes that exhibit self similarity over long time scales by a power law in the frequency spectrum S(f) = 1/fβ. The scaling exponent β is thus often interpreted as a “biomarker” of relative health and decline. New Method This paper presents a thorough comparative numerical analysis of fractal characterization techniques with specific consideration given to experimentally measured gait stride interval time series. The ideal fractal signals generated in the numerical analysis are constrained under varying lengths and biases indicative of a range of physiologically conceivable fractal signals. This analysis is to complement previous investigations of fractal characteristics in healthy and pathological gait stride interval time series, with which this study is compared. Results The results of our analysis showed that the averaged wavelet coefficient method consistently yielded the most accurate results. Comparison with Existing Methods: Class dependent methods proved to be unsuitable for physiological time series. Detrended fluctuation analysis as most prevailing method in the literature exhibited large estimation variances. Conclusions The comparative numerical analysis and experimental applications provide a thorough basis for determining an appropriate and robust method for measuring and comparing a physiologically meaningful biomarker, the spectral index β. In consideration of the constraints of application, we note the significant drawbacks of detrended fluctuation analysis and conclude that the averaged wavelet coefficient method can provide reasonable consistency and accuracy for characterizing these fractal time series. PMID:24200509

  2. Measurement report on the LHC injection kicker ripple denition and maximum pulse length (MD 1268)

    CERN Document Server

    Bartmann, Wolfgang; Kotzian, Gerd; Stoel, Linda; Velotti, Francesco Maria; Vlachodimitropoulos, Vasileios; Wiesner, Christoph; CERN. Geneva. ATS Department

    2016-01-01

    The present LHC lling scheme uses a batch spacing which corresponds to the design report specication of the injection kicker rise time. A reduction of the batch spacing can be directly used to increase luminosity without detrimental eect on beam stability. Therefore, measurements were performed to understand if a tighter batch spacing would lead to increased injection oscillations of a the rst and last bunches of a bunch train and eventually also a growth of the transverse emittance. The results of theses measurement were used to dene the minimum possible batch spacing for an acceptable emittance growth. Another measurement was performed to test if a batch consisting of 320 bunches can be injected instead of the nominal 288 bunch trains. This bunch train is dierently produced in the LHC injectors and features an optimum between beam stability and luminosity gain. The pulse length of the injection kicker was measured to ensure the full batch can be injected at once.

  3. Comparison of Echo 7 field line length measurements to magnetospheric model predictions

    International Nuclear Information System (INIS)

    Nemzek, R.J.; Winckler, J.R.; Malcolm, P.R.

    1992-01-01

    The Echo 7 sounding rocket experiment injected electron beams on central tail field lines near L = 6.5. Numerous injections returned to the payload as conjugate echoes after mirroring in the southern hemisphere. The authors compare field line lengths calculated from measured conjugate echo bounce times and energies to predictions made by integrating electron trajectories through various magnetospheric models: the Olson-Pfitzer Quiet and Dynamic models and the Tsyganenko-Usmanov model. Although Kp at launch was 3-, quiet time magnetic models est fit the echo measurements. Geosynchronous satellite magnetometer measurements near the Echo 7 field lies during the flight were best modeled by the Olson-Pfitzer Dynamic Model and the Tsyganenko-Usmanov model for Kp = 3. The discrepancy between the models that best fit the Echo 7 data and those that fit the satellite data was most likely due to uncertainties in the small-scale configuration of the magnetospheric models. The field line length measured by the conjugate echoes showed some temporal variation in the magnetic field, also indicated by the satellite magnetometers. This demonstrates the utility an Echo-style experiment could have in substorm studies

  4. Analytical model and error analysis of arbitrary phasing technique for bunch length measurement

    Science.gov (United States)

    Chen, Qushan; Qin, Bin; Chen, Wei; Fan, Kuanjun; Pei, Yuanji

    2018-05-01

    An analytical model of an RF phasing method using arbitrary phase scanning for bunch length measurement is reported. We set up a statistical model instead of a linear chirp approximation to analyze the energy modulation process. It is found that, assuming a short bunch (σφ / 2 π → 0) and small relative energy spread (σγ /γr → 0), the energy spread (Y =σγ 2) at the exit of the traveling wave linac has a parabolic relationship with the cosine value of the injection phase (X = cosφr|z=0), i.e., Y = AX2 + BX + C. Analogous to quadrupole strength scanning for emittance measurement, this phase scanning method can be used to obtain the bunch length by measuring the energy spread at different injection phases. The injection phases can be randomly chosen, which is significantly different from the commonly used zero-phasing method. Further, the systematic error of the reported method, such as the influence of the space charge effect, is analyzed. This technique will be especially useful at low energies when the beam quality is dramatically degraded and is hard to measure using the zero-phasing method.

  5. Development of a scanning tunneling potentiometry system for measurement of electronic transport at short length scales

    Science.gov (United States)

    Rozler, Michael

    It is clear that complete understanding of macroscopic properties of materials is impossible without a thorough knowledge of behavior at the smallest length scales. While the past 25 years have witnessed major advances in a variety of techniques that probe the nanoscale properties of matter, electrical transport measurements -- the heart of condensed matter research -- have lagged behind, never progressing beyond bulk measurements. This thesis describes a scanning tunneling potentiometry (STP) system developed to simultaneously map the transport-related electrochemical potential distribution of a biased sample along with its surface topography, extending electronic transport measurements to the nanoscale. Combining a novel sample biasing technique with a continuous current-nulling feedback scheme pushes the noise performance of the measurement to its fundamental limit - the Johnson noise of the STM tunnel junction. The resulting 130 nV voltage sensitivity allows us to spatially resolve local potentials at scales down to 2 nm, while maintaining atomic scale STM imaging, all at scan sizes of up to 15 microns. A mm-range two-dimensional coarse positioning stage and the ability to operate from liquid helium to room temperature with a fast turn-around time greatly expand the versatility of the instrument. Use of carefully selected model materials, combined with excellent topographic and voltage resolution has allowed us to distinguish measurement artifacts caused by surface roughness from true potentiometric features, a major problem in previous STP measurements. The measurements demonstrate that STP can produce physically meaningful results for homogeneous transport as well as non-uniform conduction dominated by material microstructures. Measurements of several physically interesting materials systems are presented as well, revealing new behaviors at the smallest length sales. The results establish scanning tunneling potentiometry as a useful tool for physics and

  6. Effect of e-learning on quality of cervical-length measurements.

    Science.gov (United States)

    van Os, M A; van der Ven, A J; Bloemendaal, P M; Pajkrt, E; de Groot, C J M; Mol, B W J; Haak, M C

    2015-09-01

    To assess the effect of implementation of a newly developed e-learning module on the quality of cervical-length measurements. With the introduction of cervical-length (CL) measurement in a research setting, a CL measurement e-learning module (CLEM) was developed with the purpose to enhance the knowledge and skills of experienced ultrasonographers. CLEM was designed specifically for ultrasonographers who perform ultrasound in a general obstetrical practice but who do not regularly perform CL measurements. CLEM consists of five theoretical questions and three caliper-placement tests to learn the CL measurement technique. The quality of the CL measurements of CLEM participants was compared with images of non-participants using a CL measurement image score (CIS), defined as the sum of six items which assess the quality of the image. Each CLEM participant submitted five CL images and the images of non-CLEM participants were selected randomly from an ultrasound database. The CIS of the CLEM participants (n = 61) were significantly higher than those of non-CLEM participants (n = 23) (164.9 vs 155.6, respectively; P = 0.03). Visualization of the internal os and positioning of the calipers on the internal and external ora were found to have significantly higher CIS among the CLEM participants than among the non-CLEM participants (P = 0.001 and P < 0.001, respectively). Introducing CLEM may improve the quality of CL measurements obtained by trained and untrained sonographers. Copyright © 2014 ISUOG. Published by John Wiley & Sons Ltd.

  7. Effects of energy chirp on bunch length measurement in linear accelerator beams

    Science.gov (United States)

    Sabato, L.; Arpaia, P.; Giribono, A.; Liccardo, A.; Mostacci, A.; Palumbo, L.; Vaccarezza, C.; Variola, A.

    2017-08-01

    The effects of assumptions about bunch properties on the accuracy of the measurement method of the bunch length based on radio frequency deflectors (RFDs) in electron linear accelerators (LINACs) are investigated. In particular, when the electron bunch at the RFD has a non-negligible energy chirp (i.e. a correlation between the longitudinal positions and energies of the particle), the measurement is affected by a deterministic intrinsic error, which is directly related to the RFD phase offset. A case study on this effect in the electron LINAC of a gamma beam source at the Extreme Light Infrastructure-Nuclear Physics (ELI-NP) is reported. The relative error is estimated by using an electron generation and tracking (ELEGANT) code to define the reference measurements of the bunch length. The relative error is proved to increase linearly with the RFD phase offset. In particular, for an offset of {{7}\\circ} , corresponding to a vertical centroid offset at a screen of about 1 mm, the relative error is 4.5%.

  8. Determination of {pi}{pi} scattering lengths from measurement of {pi}{sup +{pi}-} atom lifetime

    Energy Technology Data Exchange (ETDEWEB)

    Adeva, B. [Santiago de Compostela University (Spain); Afanasyev, L. [JINR Dubna (Russian Federation); Benayoun, M. [LPNHE des Universites Paris VI/VII, IN2P3-CNRS (France); Benelli, A. [Zurich University (Switzerland); Berka, Z. [Czech Technical University in Prague, Prague (Czech Republic); Brekhovskikh, V. [IHEP Protvino (Russian Federation); Caragheorgheopol, G. [IFIN-HH, National Institute for Physics and Nuclear Engineering, Bucharest (Romania); Cechak, T. [Czech Technical University in Prague, Prague (Czech Republic); Chiba, M. [Tokyo Metropolitan University (Japan); Chliapnikov, P.V. [IHEP Protvino (Russian Federation); Ciocarlan, C.; Constantinescu, S. [IFIN-HH, National Institute for Physics and Nuclear Engineering, Bucharest (Romania); Costantini, S. [Basel University (Switzerland); Curceanu, C. [IFIN-HH, National Institute for Physics and Nuclear Engineering, Bucharest (Romania); Doskarova, P. [Czech Technical University in Prague, Prague (Czech Republic); Dreossi, D. [INFN, Sezione di Trieste and Trieste University, Trieste (Italy); Drijard, D., E-mail: Daniel.Drijard@cern.ch [CERN, Geneva (Switzerland); Dudarev, A. [JINR Dubna (Russian Federation); Ferro-Luzzi, M. [CERN, Geneva (Switzerland); Fungueirino Pazos, J.L. [Santiago de Compostela University (Spain)

    2011-10-05

    The DIRAC experiment at CERN has achieved a sizeable production of {pi}{sup +{pi}-} atoms and has significantly improved the precision on its lifetime determination. From a sample of 21 227 atomic pairs, a 4% measurement of the S-wave {pi}{pi} scattering length difference |a{sub 0}-a{sub 2}|=(0.2533{sub -0.0078}{sup +0.0080}|{sub stat}{sup +0.0078}{sub -0.0073}|{sub syst})M{sub {pi}}{sup +-1} has been attained, providing an important test of Chiral Perturbation Theory.

  9. Direct measurement of sub-Debye-length attraction between oppositely charged surfaces.

    Science.gov (United States)

    Kampf, Nir; Ben-Yaakov, Dan; Andelman, David; Safran, S A; Klein, Jacob

    2009-09-11

    Using a surface force balance with fast video analysis, we have measured directly the attractive forces between oppositely charged solid surfaces (charge densities sigma(+), sigma(-)) across water over the entire range of interaction, in particular, at surface separations D below the Debye screening length lambda(S). At very low salt concentration we find a long-ranged attraction between the surfaces (onset ca. 100 nm), whose variation at D

  10. Improvement on a Michelson interferometer for bunch length measurement of a femtosecond accelerator

    International Nuclear Information System (INIS)

    Lin Xuling; Bei Hua; Zhang Jianbing; Dai Zhimin

    2009-01-01

    Based on the femtosecond accelerator facility at Shanghai Institute of Applied Physics (SINAP), a conventional far-infrared Michelson interferometer was built to measure the bunch length by means of optical autocorrelation. However, according to the preliminary experiment result, the resolution of interferometer is not good enough, because the mirror-driving mechanism makes the moving mirror tend to tilt or wobble as it retards. Considering of the allowable errors, we calculate the maximum allowable titling angle of the moving mirror, and discuss the alignment plan in this paper. (authors)

  11. Temperature gradient scale length measurement: A high accuracy application of electron cyclotron emission without calibration

    Energy Technology Data Exchange (ETDEWEB)

    Houshmandyar, S., E-mail: houshmandyar@austin.utexas.edu; Phillips, P. E.; Rowan, W. L. [Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas 78712 (United States); Yang, Z. J. [Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Hubbard, A. E.; Rice, J. E.; Hughes, J. W.; Wolfe, S. M. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02129 (United States)

    2016-11-15

    Calibration is a crucial procedure in electron temperature (T{sub e}) inference from a typical electron cyclotron emission (ECE) diagnostic on tokamaks. Although the calibration provides an important multiplying factor for an individual ECE channel, the parameter ΔT{sub e}/T{sub e} is independent of any calibration. Since an ECE channel measures the cyclotron emission for a particular flux surface, a non-perturbing change in toroidal magnetic field changes the view of that channel. Hence the calibration-free parameter is a measure of T{sub e} gradient. B{sub T}-jog technique is presented here which employs the parameter and the raw ECE signals for direct measurement of electron temperature gradient scale length.

  12. Evaluation of a multimode fiber optic low coherence interferometer for path length resolved Doppler measurments of diffuse light

    NARCIS (Netherlands)

    Varghese, Babu; Rajan, Vinayakrishnan; van Leeuwen, Ton; Steenbergen, Wiendelt

    2007-01-01

    The performance of a graded index multimode fiber optic low coherence Mach-Zehnder interferometer with phase modulation is analyzed. Investigated aspects were its ability to measure path length distributions and to perform path length resolved Doppler measurements of multiple scattered photons in a

  13. Evaluation of a multimode fiber optic low coherence interferometer for path length resolved Doppler measurements of diffuse light

    NARCIS (Netherlands)

    Varghese, Babu; Rajan, Vinayakrishnan; van Leeuwen, Ton G.; Steenbergen, Wiendelt

    2007-01-01

    The performance of a graded index multimode fiber optic low coherence Mach-Zehnder interferometer with phase modulation is analyzed. Investigated aspects were its ability to measure path length distributions and to perform path length resolved Doppler measurements of multiple scattered photons in a

  14. Reliability and short-term intra-individual variability of telomere length measurement using monochrome multiplexing quantitative PCR.

    Directory of Open Access Journals (Sweden)

    Sangmi Kim

    Full Text Available Studies examining the association between telomere length and cancer risk have often relied on measurement of telomere length from a single blood draw using a real-time PCR technique. We examined the reliability of telomere length measurement using sequential samples collected over a 9-month period.Relative telomere length in peripheral blood was estimated using a single tube monochrome multiplex quantitative PCR assay in blood DNA samples from 27 non-pregnant adult women (aged 35 to 74 years collected in 7 visits over a 9-month period. A linear mixed model was used to estimate the components of variance for telomere length measurements attributed to variation among women and variation between time points within women. Mean telomere length measurement at any single visit was not significantly different from the average of 7 visits. Plates had a significant systematic influence on telomere length measurements, although measurements between different plates were highly correlated. After controlling for plate effects, 64% of the remaining variance was estimated to be accounted for by variance due to subject. Variance explained by time of visit within a subject was minor, contributing 5% of the remaining variance.Our data demonstrate good short-term reliability of telomere length measurement using blood from a single draw. However, the existence of technical variability, particularly plate effects, reinforces the need for technical replicates and balancing of case and control samples across plates.

  15. Simultaneous measurement of focal length and index of refraction of a microlens using a compound microscope

    International Nuclear Information System (INIS)

    Chollet, Franck; Ashraf, Mohammed

    2009-01-01

    The fabrication of microlenses has spurred a lot of interest and resulted in multiple techniques of fabrication in the past decade. However the metrology of these lenses has received less attention and remains a complex and time-consuming task that does not allow frequent control during development and manufacturing. We propose a simple technique based on a standard compound microscope that would allow measuring the focal length of a plano-convex lens and at the same time obtain a measure of the index of refraction of the lens material. The method relies on observing the different images of an object placed in the illumination path of the microscope. Among these images, some are created by the light going through the lens and others by its reflection on the surface. We show that with the image distance and size it is possible to retrieve the focal length and the average index of refraction of the lens material in the case of quasi-spherical lenses. The accuracy obtained by the technique is better than a few per cent and its cost is negligible as it only uses existing equipment

  16. The impact of length of stay on recovery measures in faith-based addiction treatment.

    Science.gov (United States)

    Lashley, Mary

    2018-03-30

    To determine the impact of length of stay among homeless men in faith-based residential addictions recovery on physical activity, depression, self-esteem, and nicotine dependence. A time series design was utilized to measure changes in the four quality measures at program entry and at 3, 6, and 9 months following admission. The sample consisted of 175 homeless residents enrolled in a faith-based residential recovery program. Paired t tests were used to determine the change in average instrument response from admission to each follow-up period. Analysis of variance (ANOVA) and Tukey posthoc tests were used to assess for differences in length of stay between demographic variables. Statistically significant improvements were noted in self-esteem and depressive symptomatology at 3 and 6 months following admission and in physical activity levels at 3 months following admission. Nicotine dependence scores declined at 3 and 6 months but were not statistically significant. Time spent in this faith-based spiritual recovery program had a significant impact on depression, self-esteem, and physical activity. Recommendations for future study include conducting research to analyze the relationship between distinct program elements and quality indicators and comparing faith-based programs to other similar programs and to publicly funded secular recovery programs. © 2018 Wiley Periodicals, Inc.

  17. Recent high-accuracy measurements of the 1S0 neutron-neutron scattering length

    International Nuclear Information System (INIS)

    Howell, C.R.; Chen, Q.; Gonzalez Trotter, D.E.; Salinas, F.; Crowell, A.S.; Roper, C.D.; Tornow, W.; Walter, R.L.; Carman, T.S.; Hussein, A.; Gibbs, W.R.; Gibson, B.F.; Morris, C.; Obst, A.; Sterbenz, S.; Whitton, M.; Mertens, G.; Moore, C.F.; Whiteley, C.R.; Pasyuk, E.; Slaus, I.; Tang, H.; Zhou, Z.; Gloeckle, W.; Witala, H.

    2000-01-01

    This paper reports two recent high-accuracy determinations of the 1 S 0 neutron-neutron scattering length, a nn . One was done at the Los Alamos National Laboratory using the π - d capture reaction to produce two neutrons with low relative momentum. The neutron-deuteron (nd) breakup reaction was used in other measurement, which was conducted at the Triangle Universities Nuclear Laboratory. The results from the two determinations were consistent with each other and with previous values obtained using the π - d capture reaction. The value obtained from the nd breakup measurements is a nn = -18.7 ± 0.1 (statistical) ± 0.6 (systematic) fm, and the value from the π - d capture experiment is a nn = -18.50 ± 0.05 ± 0.53 fm. The recommended value is a nn = -18.5 ± 0.3 fm. (author)

  18. An apparatus to measure water optical attenuation length for LHAASO-MD

    Science.gov (United States)

    Li, Cong; Xiao, Gang; Feng, Shaohui; Wang, Lingyu; Li, Xiurong; Zuo, Xiong; Cheng, Ning; Wang, Hui; Gao, Bo; Duan, Zhihao; Liu, Jia; He, Huihai; Saeed, Mohsin; Lhaaso Collaboration

    2018-06-01

    The large high altitude air shower observatory (LHAASO) is being constructed at 4400 m a.s.l. in Daocheng, Sichuan Province, aiming to reveal the secrets of cosmic rays origin. And it has the largest surface muon detector array in the world. Due to the needs of calibration and construction of muon detector, we developed a water optical attenuation measurement device using an 8 m long water tank. The results are presented for filtered water at wavelength of 405 nm, which proves this apparatus can reach an accuracy of about 20% at 100 m. This apparatus has not only a high precision measurement of water attenuation length up to 100 m but is also very convenient to be used, which is crucial for water optical properties study during LHAASO detector construction.

  19. Diffusion length measurements in bulk and epitaxially grown 3-5 semiconductors using charge collection microscopy

    Science.gov (United States)

    Leon, R. P.

    1987-01-01

    Diffusion lengths and surface recombination velocities were measured in GaAs diodes and InP finished solar cells. The basic techniques used was charge collection microscopy also known as electron beam induced current (EBIC). The normalized currents and distances from the pn junction were read directly from the calibrated curves obtained while using the line scan mode in an SEM. These values were then equated to integral and infinite series expressions resulting from the solution of the diffusion equation with both extended generation and point generation functions. This expands previous work by examining both thin and thick samples. The surface recombination velocity was either treated as an unknown in a system of two equations, or measured directly using low e(-) beam accelerating voltages. These techniques give accurate results by accounting for the effects of surface recombination and the finite size of the generation volume.

  20. Bunch length measurements using electro-optical sampling at the SLS linac

    International Nuclear Information System (INIS)

    Winter, A.

    2004-07-01

    A mode-locked titanium-sapphire laser with 15 fs pulse width is used to determine the time profile of the picosecond electron bunches in the Swiss light source linac of the Paul Scherrer Institute, Villigen Switzerland. This was done using the electro-optic effect in Zinc-Telluride crystals and sampling the change induced by coherent transition radiation with the TiSa laser. The development, implementation and results of an analogue synchronisation system to synchronise the repetition rate of the TiSa laser to the radio frequency of the accelerator with a short term stability of 40 fs is presented. The experimental setup of the bunch length measurements is described and results are presented on the coincidence measurements between the laser pulses and the coherent transition radiation pulses generated by the electron bunches. (orig.)

  1. Measurement of clavicular length and shortening after a midshaft clavicular fracture: Spatial digitization versus planar roentgen photogrammetry.

    Science.gov (United States)

    Stegeman, Sylvia A; de Witte, Pieter Bas; Boonstra, Sjoerd; de Groot, Jurriaan H; Nagels, Jochem; Krijnen, Pieta; Schipper, Inger B

    2016-08-01

    Clavicular shortening after fracture is deemed prognostic for clinical outcome and is therefore generally assessed on radiographs. It is used for clinical decision making regarding operative or non-operative treatment in the first 2weeks after trauma, although the reliability and accuracy of the measurements are unclear. This study aimed to assess the reliability of roentgen photogrammetry (2D) of clavicular length and shortening, and to compare these with 3D-spatial digitization measurements, obtained with an electromagnetic recording system (Flock of Birds). Thirty-two participants with a consolidated non-operatively treated two or multi-fragmented dislocated midshaft clavicular fracture were analysed. Two observers measured clavicular lengths and absolute and proportional clavicular shortening on radiographs taken before and after fracture consolidation. The clavicular lengths were also measured with spatial digitization. Inter-observer agreement on the radiographic measurements was assessed using the Intraclass Correlation Coefficient (ICC). Agreement between the radiographic and spatial digitization measurements was assessed using a Bland-Altman plot. The inter-observer agreement on clavicular length, and absolute and proportional shortening on trauma radiographs was almost perfect (ICC>0.90), but moderate for absolute shortening after consolidation (ICC=0.45). The Bland-Altman plot compared measurements of length on AP panorama radiographs with spatial digitization and showed that planar roentgen photogrammetry resulted in up to 37mm longer and 34mm shorter measurements than spatial digitization. Measurements of clavicular length on radiographs are highly reliable between observers, but may not reflect the actual length and shortening of the clavicle when compared to length measurements with spatial digitization. We recommend to use proportional shortening when measuring clavicular length or shortening on radiographs for clinical decision making. Copyright

  2. Foot length measurements of newborns of high and low risk pregnancies.

    Science.gov (United States)

    Salge, Ana Karina Marques; Rocha, Érika Lopes; Gaíva, Maria Aparecida Munhoz; Castral, Thaíla Correa; Guimarães, Janaína Valadares; Xavier, Raphaela Maioni

    2017-03-09

    Comparing foot length measurements of newborns in high and low risk pregnancies at a public hospital in Goiânia, GO, Brazil. A cross-sectional study carried out between April, 2013 and May, 2015, with a sample consisting of 180 newborns; 106 infants of women from high-risk pregnancies and 74 of women from low-risk pregnancies. Data were descriptively analyzed. Foot length measurement was performed using a stiff transparent plastic ruler, graduated in millimeters. The length of both feet was measured from the tip of the hallux (big toe) to the end of the heel. A statistically significant relationship was found between the foot length and newborn's weight, between the cephalic and thoracic perimeters in the high-risk group and between the cephalic perimeter in the control group. There is a need for creating cut-off points to identify newborns with intrauterine growth disorders using foot length. Comparar as medidas do comprimento hálux-calcâneo de recém-nascidos em gestações de alto e baixo risco em um hospital público de Goiânia, GO. Estudo transversal, realizado no período de abril de 2013 a maio de 2015, cuja amostra constituiu-se de 180 recém-nascidos, 106 filhos de mulheres com gestação de alto risco e 74 de mulheres com gestação de baixo risco. Os dados foram analisados descritivamente. A medida do comprimento hálux-calcâneo foi realizada utilizando-se de régua plástica transparente rígida, graduada em milímetros. Foram medidos ambos os pés, aferindo-se o comprimento da ponta do hálux até a extremidade do calcâneo. Foi encontrada relação estatisticamente significante entre o comprimento hálux-calcâneo e o peso do recém-nascido, entre os perímetros cefálico e torácico no grupo de alto risco e entre o perímetro cefálico no grupo controle. Existe necessidade da criação de pontos de corte para identificar recém-nascidos com desvios de crescimento intrauterino utilizando-se do comprimento hálux-calcâneo. Comparar las mediciones

  3. An automated A-value measurement tool for accurate cochlear duct length estimation.

    Science.gov (United States)

    Iyaniwura, John E; Elfarnawany, Mai; Ladak, Hanif M; Agrawal, Sumit K

    2018-01-22

    There has been renewed interest in the cochlear duct length (CDL) for preoperative cochlear implant electrode selection and postoperative generation of patient-specific frequency maps. The CDL can be estimated by measuring the A-value, which is defined as the length between the round window and the furthest point on the basal turn. Unfortunately, there is significant intra- and inter-observer variability when these measurements are made clinically. The objective of this study was to develop an automated A-value measurement algorithm to improve accuracy and eliminate observer variability. Clinical and micro-CT images of 20 cadaveric cochleae specimens were acquired. The micro-CT of one sample was chosen as the atlas, and A-value fiducials were placed onto that image. Image registration (rigid affine and non-rigid B-spline) was applied between the atlas and the 19 remaining clinical CT images. The registration transform was applied to the A-value fiducials, and the A-value was then automatically calculated for each specimen. High resolution micro-CT images of the same 19 specimens were used to measure the gold standard A-values for comparison against the manual and automated methods. The registration algorithm had excellent qualitative overlap between the atlas and target images. The automated method eliminated the observer variability and the systematic underestimation by experts. Manual measurement of the A-value on clinical CT had a mean error of 9.5 ± 4.3% compared to micro-CT, and this improved to an error of 2.7 ± 2.1% using the automated algorithm. Both the automated and manual methods correlated significantly with the gold standard micro-CT A-values (r = 0.70, p value measurement tool using atlas-based registration methods was successfully developed and validated. The automated method eliminated the observer variability and improved accuracy as compared to manual measurements by experts. This open-source tool has the potential to benefit

  4. Retrieval of Effective Correlation Length and Snow Water Equivalent from Radar and Passive Microwave Measurements

    Directory of Open Access Journals (Sweden)

    Juha Lemmetyinen

    2018-01-01

    Full Text Available Current methods for retrieving SWE (snow water equivalent from space rely on passive microwave sensors. Observations are limited by poor spatial resolution, ambiguities related to separation of snow microstructural properties from the total snow mass, and signal saturation when snow is deep (~>80 cm. The use of SAR (Synthetic Aperture Radar at suitable frequencies has been suggested as a potential observation method to overcome the coarse resolution of passive microwave sensors. Nevertheless, suitable sensors operating from space are, up to now, unavailable. Active microwave retrievals suffer, however, from the same difficulties as the passive case in separating impacts of scattering efficiency from those of snow mass. In this study, we explore the potential of applying active (radar and passive (radiometer microwave observations in tandem, by using a dataset of co-incident tower-based active and passive microwave observations and detailed in situ data from a test site in Northern Finland. The dataset spans four winter seasons with daily coverage. In order to quantify the temporal variability of snow microstructure, we derive an effective correlation length for the snowpack (treated as a single layer, which matches the simulated microwave response of a semi-empirical radiative transfer model to observations. This effective parameter is derived from radiometer and radar observations at different frequencies and frequency combinations (10.2, 13.3 and 16.7 GHz for radar; 10.65, 18.7 and 37 GHz for radiometer. Under dry snow conditions, correlations are found between the effective correlation length retrieved from active and passive measurements. Consequently, the derived effective correlation length from passive microwave observations is applied to parameterize the retrieval of SWE using radar, improving retrieval skill compared to a case with no prior knowledge of snow-scattering efficiency. The same concept can be applied to future radar

  5. Contingent use of fetal fibronectin testing and cervical length measurement in women with preterm labour.

    Science.gov (United States)

    Audibert, François; Fortin, Suzanne; Delvin, Edgard; Djemli, Anissa; Brunet, Suzanne; Dubé, Johanne; Fraser, William D

    2010-04-01

    To evaluate the contingent use of fetal fibronectin (fFN) testing and cervical length (CL) measurement to predict preterm delivery, and to validate the use of phosphorylated IGFBP-1 as a predictor of preterm delivery. We recruited 71 women with a clinical diagnosis of preterm labour between 24 and 34 weeks, and tested for the presence of fFN and IGFBP-1 in the cervicovaginal secretions of all women immediately before CL measurement. Among the 66 women with complete outcome, four were excluded from the final analysis as two had assessment for fFN but no CL measurement, and another two had CL measured but no screening for fFN. Among 62 women with complete results, the mean gestational age at recruitment was 29.4 +/- 2.5 weeks. Six women (9.6%) delivered within two weeks of assessment, and 14 (22.5%) delivered before 34 weeks. A positive fFN test resulted in a sensitivity of 83%, a specificity of 84%, a positive predictive value of 36%, and a negative predictive value of 98% for delivery within two weeks; for CL contingent use of fFN (in which the test was assumed to be positive if CL contingent use protocol, only one third of women needed fFN screening after CL measurement. In this study, IGFBP-1 screening did not predict preterm delivery and fFN screening provided the best predictive capacity. A policy of contingent use of testing for fFN after CL measurement, or contingent use of CL measurement after fFN screening (depending on available resources) is a promising approach to limit use of resources.

  6. The validity of cone-beam computed tomography in measuring root canal length using a gold standard

    NARCIS (Netherlands)

    Liang, Y.H.; Jiang, L.; Chen, C.; Gao, X.J.; Wesselink, P.R.; Wu, M.K.; Shemesh, H.

    2013-01-01

    Introduction The distance between a coronal reference point and the major apical foramen is important for working length determination. The aim of this in vitro study was to determine the accuracy of root canal length measurements performed with cone-beam computed tomographic (CBCT) scans using a

  7. Method for single-shot measurement of picosecond laser pulse-lengths without electronic time dispersion

    International Nuclear Information System (INIS)

    Kyrala, G.A.

    1987-01-01

    A two-source shear pattern recording is proposed as a method for single-shot measurement of the pulse shape from nearly monochromatic sources whose pulse lengths are shorter than their coherence times. The basis of this method relies on the assertion that if two identical electromagnetic pulses are recombined with a time delay greater than the sum of their pulse widths, the recordable spatial pattern has no fringes in it. At an arbitrary delay, translated into an actual spatial recording position, the recorded modulated intensity will sample the corresponding laser intensity at that delay time, but with a modulation due to the coherence function of the electromagnetic pulse. Two arrangements are proposed for recording the pattern. The principles, the design parameters, and the methodologies of these arrangements are presented. Resolutions of the configurations and their limitations are given as well

  8. Residual standard deviation: Validation of a new measure of dual-task cost in below-knee prosthesis users.

    Science.gov (United States)

    Howard, Charla L; Wallace, Chris; Abbas, James; Stokic, Dobrivoje S

    2017-01-01

    We developed and evaluated properties of a new measure of variability in stride length and cadence, termed residual standard deviation (RSD). To calculate RSD, stride length and cadence are regressed against velocity to derive the best fit line from which the variability (SD) of the distance between the actual and predicted data points is calculated. We examined construct, concurrent, and discriminative validity of RSD using dual-task paradigm in 14 below-knee prosthesis users and 13 age- and education-matched controls. Subjects walked first over an electronic walkway while performing separately a serial subtraction and backwards spelling task, and then at self-selected slow, normal, and fast speeds used to derive the best fit line for stride length and cadence against velocity. Construct validity was demonstrated by significantly greater increase in RSD during dual-task gait in prosthesis users than controls (group-by-condition interaction, stride length p=0.0006, cadence p=0.009). Concurrent validity was established against coefficient of variation (CV) by moderate-to-high correlations (r=0.50-0.87) between dual-task cost RSD and dual-task cost CV for both stride length and cadence in prosthesis users and controls. Discriminative validity was documented by the ability of dual-task cost calculated from RSD to effectively differentiate prosthesis users from controls (area under the receiver operating characteristic curve, stride length 0.863, p=0.001, cadence 0.808, p=0.007), which was better than the ability of dual-task cost CV (0.692, 0.648, respectively, not significant). These results validate RSD as a new measure of variability in below-knee prosthesis users. Future studies should include larger cohorts and other populations to ascertain its generalizability. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Spontaneous oscillation of tension and sarcomere length in skeletal myofibrils. Microscopic measurement and analysis.

    Science.gov (United States)

    Anazawa, T; Yasuda, K; Ishiwata, S

    1992-05-01

    We have devised a simple method for measuring tension development of single myofibrils by micromanipulation with a pair of glass micro-needles. The tension was estimated from the deflection of a flexible needle under an inverted phase-contrast microscope equipped with an image processor, so that the tension development is always accompanied by the shortening of the myofibril (auxotonic condition) in the present setup. The advantage of this method is that the measurement of tension (1/30 s for time resolution and about 0.05 micrograms for accuracy of tension measurement; 0.05 microns as a spatial resolution for displacement of the micro-needle) and the observation of sarcomere structure are possible at the same time, and the technique to hold myofibrils, even single myofibrils, is very simple. This method has been applied to study the tension development of glycerinated skeletal myofibrils under the condition where spontaneous oscillation of sarcomeres is induced, i.e., the coexistence of MgATP, MgADP and inorganic phosphate without free Ca2+. Under this condition, we found that the tension of myofibrils spontaneously oscillates accompanied by the oscillation of sarcomere length with a main period of a few seconds; the period was lengthened and shortened with stretch and release of myofibrils. A possible mechanism of the oscillation is discussed.

  10. Preliminary evaluation of STRIDE programme in primary schools of Malaysia.

    Science.gov (United States)

    Hanjeet, K; Wan Rozita, W M; How, T B; Santhana Raj, L; Baharudin, Omar

    2007-12-01

    The Students' Resilience and Interpersonal Skills Development Education (STRIDE) is a preventive drug education programme. The rational of this programme is that preventive drug education has to begin early in age, before the development of social attitudes and behaviour of students. A pre and a post intervention surveys were performed to evaluate the impact of this programme. Nine schools from three states were identified to participate in the intervention. These schools were selected based on their locations in high-drug-use areas (where the prevalence of drug use exceeds 0.5% of the student population). The new intervention curriculum was put into practice for three months in the nine schools. The overall scores obtained by each respondent to assess their knowledge on drugs and its implications were analysed. The results showed that the programme made a positive impact from the pre to post intervention programme by using the Wilcoxon Signed Rank Test (p < 0.05). A high percentage of the questions showed significant evidence through the McNemar matched pair Chi-Squared test with Bonferonni correction that there were positive shifts in the answers by comparing the pre and post intervention results (p < 0.05). Recommendations have been discussed with the Ministry of Education to integrate this programme into the national primary school curriculum.

  11. An accelerometric measure of the gait pattern in horses after the administration of sublingual detomidine.

    Science.gov (United States)

    López-Sanromán, F J; de la Riva Andrés, S; Holmbak-Petersen, R; Pérez-Nogués, M; Forés Jackson, P; Santos González, M

    2014-10-01

    The locomotor pattern alterations produced after the administration of a sublingual detomidine gel was measured by an accelerometric method in horses. Using a randomized two-way crossover design, all animals (n = 6) randomly received either detomidine gel or a placebo administered sublingually. A triaxial accelerometric device was used for gait assessment 15 minutes before (baseline) and every 10 minutes after each treatment for a period of 180 minutes. Eight different parameters were calculated, including speed, stride frequency, stride length, regularity, dorsoventral, propulsion, mediolateral, and total power. Force of acceleration and the three components of power were also calculated. Significant statistical differences were observed between groups in all the parameters but stride length. The majority of significant changes started between 30 and 70 minutes after drug administration and lasted for 160 minutes. This route of administration is definitely useful in horses in which a prolonged sedation is required, with stability being a major concern. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Ultrasonic motion analysis system - measurement of temporal and spatial gait parameters

    NARCIS (Netherlands)

    Huitema, RB; Hof, AL; Postema, K

    The duration of stance and swing phase and step and stride length are important parameters in human gait. In this technical note a low-cost ultrasonic motion analysis system is described that is capable of measuring these temporal and spatial parameters while subjects walk on the floor. By using the

  13. A method to measure the antikaon-nucleon scattering length in lattice QCD

    International Nuclear Information System (INIS)

    Lage, Michael; Meissner, Ulf-G.; Rusetsky, Akaki

    2009-01-01

    We propose a method to determine the isoscalar K-bar N scattering length on the lattice. Our method represents the generalization of Luescher's approach in the presence of inelastic channels (complex scattering length). In addition, the proposed approach allows one to find the position of the S-matrix pole corresponding the Λ(1405) resonance.

  14. Recommended number of strides for automatic assessment of gait symmetry and regularity in above-knee amputees by means of accelerometry and autocorrelation analysis

    Directory of Open Access Journals (Sweden)

    Tura Andrea

    2012-02-01

    Full Text Available Abstract Background Symmetry and regularity of gait are essential outcomes of gait retraining programs, especially in lower-limb amputees. This study aims presenting an algorithm to automatically compute symmetry and regularity indices, and assessing the minimum number of strides for appropriate evaluation of gait symmetry and regularity through autocorrelation of acceleration signals. Methods Ten transfemoral amputees (AMP and ten control subjects (CTRL were studied. Subjects wore an accelerometer and were asked to walk for 70 m at their natural speed (twice. Reference values of step and stride regularity indices (Ad1 and Ad2 were obtained by autocorrelation analysis of the vertical and antero-posterior acceleration signals, excluding initial and final strides. The Ad1 and Ad2 coefficients were then computed at different stages by analyzing increasing portions of the signals (considering both the signals cleaned by initial and final strides, and the whole signals. At each stage, the difference between Ad1 and Ad2 values and the corresponding reference values were compared with the minimum detectable difference, MDD, of the index. If that difference was less than MDD, it was assumed that the portion of signal used in the analysis was of sufficient length to allow reliable estimation of the autocorrelation coefficient. Results All Ad1 and Ad2 indices were lower in AMP than in CTRL (P Conclusions Without the need to identify and eliminate the phases of gait initiation and termination, twenty strides can provide a reasonable amount of information to reliably estimate gait regularity in transfemoral amputees.

  15. Model of vortex dynamics in superconducting films in two-coil measurements of the coherence length

    Science.gov (United States)

    Lemberger, Thomas; Loh, Yen Lee

    In two-coil measurements on superconducting films, a magnetic field from a small coil is applied to the center of the film. When the amplitude of the ac field is increased, the film undergoes a transition from the ``Meissner'' state to a state with vortices and antivortices. Ultimately, the vortex density matches the applied magnetic field and field screening is negligible. Experimentally, the field at the transition is related to the superconducting coherence length, although a full theory of the relationship is lacking. We show that the mutual inductance between drive and pickup coils, on opposite sides of the film, as a function of ac field amplitude is well-described by a phenomenological model in which vortices and antivortices appear together in the film at the radius where the induced supercurrent is strongest, and then they move through a landscape of moderately strong vortex pinning sites. Work at OSU supported by DOE-Basic Energy Sciences through Grant No. FG02-08ER46533.

  16. Effects of changing the random number stride in Monte Carlo calculations

    International Nuclear Information System (INIS)

    Hendricks, J.S.

    1991-01-01

    This paper reports on a common practice in Monte Carlo radiation transport codes which is to start each random walk a specified number of steps up the random number sequence from the previous one. This is called the stride in the random number sequence between source particles. It is used for correlated sampling or to provide tree-structured random numbers. A new random number generator algorithm for the major Monte Carlo code MCNP has been written to allow adjustment of the random number stride. This random number generator is machine portable. The effects of varying the stride for several sample problems are examined

  17. Unfavorable Strides in Cache Memory Systems (RNR Technical Report RNR-92-015

    Directory of Open Access Journals (Sweden)

    David H. Bailey

    1995-01-01

    Full Text Available An important issue in obtaining high performance on a scientific application running on a cache-based computer system is the behavior of the cache when data are accessed at a constant stride. Others who have discussed this issue have noted an odd phenomenon in such situations: A few particular innocent-looking strides result in sharply reduced cache efficiency. In this article, this problem is analyzed, and a simple formula is presented that accurately gives the cache efficiency for various cache parameters and data strides.

  18. Acoustic Measurement of the Length of Air-plasma Filament Induced by an Intense Femtosecond Laser Pulse

    Directory of Open Access Journals (Sweden)

    Wu Si-Qing

    2017-01-01

    Full Text Available The paper studies acoustic emission from air-plasma filament induced by a strong femtosecond laser pulse. Acoustic signal is detected with a sensitive directional microphone. Acoustic measurement provides a new method to determine the length of a filament. Compared with other methods, acoustic measurement is simpler, more sensitive, and with higher spatial resolution. Information of filament length is experimentally acquired through measuring acoustic pressure at different position of filament. On the basis of the relationship between acoustic signal and free-electron density in filament, profile of free-electron density is demonstrated

  19. Is sonographically measured cervical length at 37 weeks of gestation associated with intrapartum cesarean section? A prospective cohort study.

    Science.gov (United States)

    de Vries, Bradley; Narayan, Rajit; McGeechan, Kevin; Santiagu, Stanley; Vairavan, Ramesh; Burke, Minke; Phipps, Hala; Hyett, Jon

    2018-02-16

    Cesarean section rates continue to increase globally. Prediction of intrapartum cesarean section could lead to preventive measures. Our aim was to assess the association between sonographically measured cervical length at 37 weeks of gestation and cesarean section among women planning a vaginal birth. The population was women with a low-risk pregnancy or with gestational diabetes. This was a prospective cohort study conducted in a tertiary referral hospital in Sydney, Australia. In all, 212 women with a low-risk pregnancy or with gestational diabetes were recruited including 158 nulliparous and 54 parous women. Maternal demographic, clinical and ultrasound characteristics were collected at 37 weeks of gestation. Semi-Bayesian logistic regression and Markov chain Monte Carlo simulation were used to assess the relationship between cervical length and cesarean section in labor. Rates of cesarean section were 5% (2/55) for cervical length ≤20 mm, 17% (17/101) for cervical length 20-32 mm, and 27% (13/56) for cervical length >32 mm. These rates were 4, 22 and 33%, respectively, in nulliparous women. In the semi-Bayesian analysis, the odds ratio for cesarean section was 6.2 (95% confidence interval 2.2-43) for cervical length 20-32 mm and 10 (95% confidence interval 4.8-74) for cervical length >32 mm compared with the lowest quartile of cervical length, after adjusting for maternal age, parity, height, prepregnancy body mass index, gestational diabetes, induction of labor, neonatal sex and birthweight centile. Cervical length at 37 weeks of gestation is associated with intrapartum cesarean section. © 2018 Nordic Federation of Societies of Obstetrics and Gynecology.

  20. Effects of tubing length and coupling method on hearing threshold and real-ear to coupler difference measures.

    Science.gov (United States)

    Gustafson, Samantha; Pittman, Andrea; Fanning, Robert

    2013-06-01

    This tutorial demonstrates the effects of tubing length and coupling type (i.e., foam tip or personal earmold) on hearing threshold and real-ear-to-coupler difference (RECD) measures. Hearing thresholds from 0.25 kHz through 8 kHz are reported at various tubing lengths for 28 normal-hearing adults between the ages of 22 and 31 years. RECD values are reported for 14 of the adults. All measures were made with an insert earphone coupled to a standard foam tip and with an insert earphone coupled to each participant's personal earmold. Threshold and RECD measures obtained with a personal earmold were significantly different from those obtained with a foam tip on repeated measures analyses of variance. One-sample t tests showed these differences to vary systematically with increasing tubing length, with the largest average differences (7-8 dB) occurring at 4 kHz. This systematic examination demonstrates the equal and opposite effects of tubing length on threshold and acoustic measures. Specifically, as tubing length increased, sound pressure level in the ear canal decreased, affecting both hearing thresholds and the real-ear portion of the RECDs. This demonstration shows that when the same coupling method is used to obtain the hearing thresholds and RECD, equal and accurate estimates of real-ear sound pressure level are obtained.

  1. Disentangling behavior in early child development : Interpretability of early child language and its effect on utterance length measures

    NARCIS (Netherlands)

    Van Dijk, M.W.G.; Van Geert, P. L. C.

    Early child speech is often difficult to understand and interpret. Usually, these unintelligible units are not included in quantitative measures, such as MLU. In this paper, we claim that these interpretation problems have an unknown effect on utterance length measures (such as MLU), since we have

  2. 23 CFR Appendix D to Part 658 - Devices That Are Excluded From Measurement of the Length or Width of a Commercial Motor Vehicle

    Science.gov (United States)

    2010-04-01

    ...; (v) Tarp basket; (w) Tire carrier; and (x) Uppercoupler. 2. Devices excluded from length measurement... measurement are side rails running the length of the vehicle and rear doors, provided the only function of the...

  3. Distance Between the Malleoli and the GroundA New Clinical Method to Measure Leg-Length Discrepancy.

    Science.gov (United States)

    Aguilar, Estela Gomez; Domínguez, Águeda Gómez; Peña-Algaba, Carolina; Castillo-López, José M

    2017-03-01

    The aim of this work is to introduce a useful method for the clinical diagnosis of leg-length inequality: distance between the malleoli and the ground (DMG). A transversal observational study was performed on 17 patients with leg-length discrepancy. Leg-length inequality was determined with different clinical methods: with a tape measure in a supine position from the anterior superior iliac spine (ASIS) to the internal and external malleoli, as the difference between the iliac crests when standing (pelvimeter), and as asymmetry between ASISs (PALpation Meter [PALM]; A&D Medical Products Healthcare, San Jose, California). The Foot Posture Index (FPI) and the navicular drop test were also used. The DMG with Perthes rule (perpendicular to the foot when standing), the distance between the internal malleolus and the ground (DIMG), and the distance between the external malleolus and the ground were designed by the authors. The DIMG is directly related to the traditional ASIS-external malleolus measurement (P = .003), the FPI (P = .010), and the navicular drop test (P DMG) is useful for diagnosing leg-length discrepancy and is related to the ASIS-external malleolus measurement. The DIMG is significantly inversely proportional to the degree of pronation according to the FPI. Conversely, determination of leg-length discrepancy with a tape measure from the ASIS to the malleoli cannot be performed interchangeably at the level of the internal or external malleolus.

  4. Tension-referenced measures of gastrocnemius slack length and stiffness in Parkinson's disease.

    Science.gov (United States)

    Tan, Benedict; Double, Kay L; Burne, John; Diong, Joanna

    2016-12-01

    It is not known how passive muscle length and stiffness contribute to rigidity in Parkinson's disease. The objective of this study was to compare passive gastrocnemius muscle-tendon slack length and stiffness at known tension in Parkinson's disease subjects with ankle rigidity and in able-bodied people. Passive ankle torque-angle curves were obtained from 15 Parkinson's disease subjects with rigidity and 15 control subjects. Torque-angle data were used to derive passive gastrocnemius length-tension data and calculate slack length and stiffness of the gastrocnemius muscle. Between-group comparisons were made with linear models. Gastrocnemius muscle-tendon slack lengths (adjusted between-group difference, 0.01 m; 95% CI, -0.02 to 0.04 m; P = 0.37) and stiffness (adjusted between-group difference, 15.7 m -1 ; 95% CI, -8.5 to 39.9 m -1 ; P = 0.19) were not significantly different between groups. Parkinson's disease subjects with ankle rigidity did not have significantly shorter or stiffer gastrocnemius muscles compared with control subjects. © 2016 International Parkinson and Movement Disorder Society. © 2016 International Parkinson and Movement Disorder Society.

  5. Measurements of 3D slip velocities and plasma column lengths of a gliding arc discharge

    DEFF Research Database (Denmark)

    Zhu, Jiajian; Gao, Jinlong; Ehn, Andreas

    2015-01-01

    A non-thermal gliding arc discharge was generated at atmospheric pressure in an air flow. The dynamics of the plasma column and tracer particles were recorded using two synchronized high-speed cameras. Whereas the data analysis for such systems has previously been performed in 2D (analyzing......, gives more realistic insight into the convection cooling process. Additionally, with the determination of the 3D slip velocity and the 3D length of the plasma column, we give more accurate estimates for the drag force, the electric field strength, the power per unit length, and the radius...

  6. Dependence of adenine isolation efficiency on the chain length evidenced using paramagnetic particles and voltammetry measurements

    Energy Technology Data Exchange (ETDEWEB)

    Huska, Dalibor [Department of Chemistry and Biochemistry, Faculty of Agronomy, Mendel University of Agriculture and Forestry, Zemedelska 1, CZ-613 00 Brno (Czech Republic); Adam, Vojtech [Department of Chemistry and Biochemistry, Faculty of Agronomy, Mendel University of Agriculture and Forestry, Zemedelska 1, CZ-613 00 Brno (Czech Republic); Department of Animal Nutrition and Forage Production, Faculty of Agronomy, Mendel University of Agriculture and Forestry, Zemedelska 1, CZ-613 00 Brno (Czech Republic); Trnkova, Libuse [Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5, CZ-625 00 Brno (Czech Republic); Kizek, Rene [Department of Chemistry and Biochemistry, Faculty of Agronomy, Mendel University of Agriculture and Forestry, Zemedelska 1, CZ-613 00 Brno (Czech Republic)], E-mail: kizek@sci.muni.cz

    2009-05-15

    The main aim of this work was to study the dependence of oligoadenine isolation efficiency on the chain length by using paramagnetic particles covered by homo-deoxythymidines ((dT)25) with subsequent detection by adsorptive transfer technique coupled with square wave voltammetry. For this purpose, the oligonucleotides of the length A5, A10, A15, A20, A25, A30, A35, A40 and poly(A) in various concentrations were chosen. We determined that the isolation efficiency defined as 'isolated oligonucleotide concentration'/'given oligonucleotide concentration' was about 55% on average. Sequence A25 demonstrated the best binding onto microparticles surface.

  7. Dependence of adenine isolation efficiency on the chain length evidenced using paramagnetic particles and voltammetry measurements

    International Nuclear Information System (INIS)

    Huska, Dalibor; Adam, Vojtech; Trnkova, Libuse; Kizek, Rene

    2009-01-01

    The main aim of this work was to study the dependence of oligoadenine isolation efficiency on the chain length by using paramagnetic particles covered by homo-deoxythymidines ((dT)25) with subsequent detection by adsorptive transfer technique coupled with square wave voltammetry. For this purpose, the oligonucleotides of the length A5, A10, A15, A20, A25, A30, A35, A40 and poly(A) in various concentrations were chosen. We determined that the isolation efficiency defined as 'isolated oligonucleotide concentration'/'given oligonucleotide concentration' was about 55% on average. Sequence A25 demonstrated the best binding onto microparticles surface.

  8. Vertebral height as the measure of lesion length in carcinoma of the ...

    African Journals Online (AJOL)

    With the modified tech- nique it was possible to decrease treat- ment length and the number of nor- mal oesophageal mucosa in the treat- ment volume, thereby reducing the chance of treatment-related complica- tions such as strictures and ulceration. Introduction. The majority of patients with car- cinoma of the oesophagus ...

  9. Importance of epoch length and registration time on accelerometer measurements in younger children

    DEFF Research Database (Denmark)

    Dencker, M; Svensson, J; El-Naaman, B

    2012-01-01

    The aim of this study was to investigate the effect of epoch length on accumulation of minutes of physical activity per day over a spectrum of intensities, and the effect that selection of number of hours of acceptable registration required per day had on number of days that were considered accep...

  10. Improved theory of time domain reflectometry with variable coaxial cable length for electrical conductivity measurements

    Science.gov (United States)

    Although empirical models have been developed previously, a mechanistic model is needed for estimating electrical conductivity (EC) using time domain reflectometry (TDR) with variable lengths of coaxial cable. The goals of this study are to: (1) derive a mechanistic model based on multisection tra...

  11. Measurement of the length and position of the lower oesophageal sphincter by correlation of external measurements and radiographic estimations in dogs

    International Nuclear Information System (INIS)

    Waterman, A.E.; Hashim, M.A.

    1991-01-01

    Fifty dogs were investigated in order to correlate the length and position of the lower oesophageal sphincter (LOS) with external measurements. Various external measurements were taken while the dogs were anaesthetised and positioned in lateral recumbency. An oesophageal tube was then introduced into the oesophagus and thoracic radiographs were taken. The 'real internal length of the oesophagus' was calculated as the length from the lower jaw incisor tooth to the position of the oesophageal tube at the costal border of the diaphragm. A highly significant linear correlation was found between this internal length and the external length from lower jaw incisor tooth to the anterior border of the head of the 10th rib. Using oesophageal manometry, the length and position of the LOS was also studied in 25 clinically normal bitches. The mean length of the LOS was found to be 4.6 +/- 0.92 cm. The position of the LOS was a mean of 4.4 +/- 1.69 cm cranial to the costal border of the diaphragm. The findings of this study indicate that the external measurements can be used to position catheters for accurate oesophageal manometry in the dog

  12. Influence of Landscape Coverage on Measuring Spatial and Length Properties of Rock Fracture Networks: Insights from Numerical Simulation

    Science.gov (United States)

    Cao, Wenzhuo; Lei, Qinghua

    2018-01-01

    Natural fractures are ubiquitous in the Earth's crust and often deeply buried in the subsurface. Due to the difficulty in accessing to their three-dimensional structures, the study of fracture network geometry is usually achieved by sampling two-dimensional (2D) exposures at the Earth's surface through outcrop mapping or aerial photograph techniques. However, the measurement results can be considerably affected by the coverage of forests and other plant species over the exposed fracture patterns. We quantitatively study such effects using numerical simulation. We consider the scenario of nominally isotropic natural fracture systems and represent them using 2D discrete fracture network models governed by fractal and length scaling parameters. The groundcover is modelled as random patches superimposing onto the 2D fracture patterns. The effects of localisation and total coverage of landscape patches are further investigated. The fractal dimension and length exponent of the covered fracture networks are measured and compared with those of the original non-covered patterns. The results show that the measured length exponent increases with the reduced localisation and increased coverage of landscape patches, which is more evident for networks dominated by very large fractures (i.e. small underlying length exponent). However, the landscape coverage seems to have a minor impact on the fractal dimension measurement. The research findings of this paper have important implications for field survey and statistical analysis of geological systems.

  13. Measurement of laminar burning velocities and Markstein lengths of diluted hydrogen-enriched natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Miao, Haiyan; Jiao, Qi; Huang, Zuohua; Jiang, Deming [State Key Laboratory of Multiphase Flow in Power Engineering, School of Energy and Power Eng., Xi' an Jiaotong University (China)

    2009-01-15

    The laminar flame characteristics of natural gas-hydrogen-air-diluent gas (nitrogen/CO{sub 2}) mixtures were studied in a constant volume combustion bomb at various diluent ratios, hydrogen fractions and equivalence ratios. Both unstretched laminar burning velocity and Markstein length were obtained. The results showed that hydrogen fraction, diluent ratio and equivalence ratio have combined influence on laminar burning velocity and flame instability. The unstretched laminar burning velocity is reduced at a rate that is increased with the increase of the diluent ratio. The reduction effect of CO{sub 2} diluent gas is stronger than that of nitrogen diluent gas. Hydrogen-enriched natural gas with high hydrogen fraction can tolerate more diluent gas than that with low hydrogen fraction. Markstein length can either increase or decrease with the increase of the diluent ratio, depending on the hydrogen fraction of the fuel. (author)

  14. Attenuation length measurements of a liquid scintillator with LabVIEW and reliability evaluation of the device

    International Nuclear Information System (INIS)

    Gao Long; Yu Boxiang; Ding Yayun

    2013-01-01

    An attenuation length measurement device was constructed using an oscilloscope and LabVIEW for signal acquisition and processing. The performance of the device has been tested in a variety of ways. The test results show that the set-up has a good stability and high precision (sigma/mean reached 0.4 percent). Besides, the accuracy of the measurement system will decrease by about 17 percent if a filter is used. The attenuation length of a gadolinium-loaded liquid scintillator (Gd-LS) was measured as 15.10±0.35 m where Gd-LS was heavily used in the Daya Bay Neutrino Experiment. In addition, one method based on the Beer-Lambert law was proposed to investigate the reliability of the measurement device, the R-square reached 0.9995. Moreover, three purification methods for Linear Alkyl Benzene (LAB) production were compared in the experiment. (authors)

  15. Simultaneous Water Vapor and Dry Air Optical Path Length Measurements and Compensation with the Large Binocular Telescope Interferometer

    Science.gov (United States)

    Defrere, D.; Hinz, P.; Downey, E.; Boehm, M.; Danchi, W. C.; Durney, O.; Ertel, S.; Hill, J. M.; Hoffmann, W. F.; Mennesson, B.; hide

    2016-01-01

    The Large Binocular Telescope Interferometer uses a near-infrared camera to measure the optical path length variations between the two AO-corrected apertures and provide high-angular resolution observations for all its science channels (1.5-13 microns). There is however a wavelength dependent component to the atmospheric turbulence, which can introduce optical path length errors when observing at a wavelength different from that of the fringe sensing camera. Water vapor in particular is highly dispersive and its effect must be taken into account for high-precision infrared interferometric observations as described previously for VLTI/MIDI or the Keck Interferometer Nuller. In this paper, we describe the new sensing approach that has been developed at the LBT to measure and monitor the optical path length fluctuations due to dry air and water vapor separately. After reviewing the current performance of the system for dry air seeing compensation, we present simultaneous H-, K-, and N-band observations that illustrate the feasibility of our feed forward approach to stabilize the path length fluctuations seen by the LBTI nuller uses a near-infrared camera to measure the optical path length variations between the two AO-corrected apertures and provide high-angular resolution observations for all its science channels (1.5-13 microns). There is however a wavelength dependent component to the atmospheric turbulence, which can introduce optical path length errors when observing at a wavelength different from that of the fringe sensing camera. Water vapor in particular is highly dispersive and its effect must be taken into account for high-precision infrared interferometric observations as described previously for VLTI MIDI or the Keck Interferometer Nuller. In this paper, we describe the new sensing approach that has been developed at the LBT to measure and monitor the optical path length fluctuations due to dry air and water vapor separately. After reviewing the current

  16. Application of a Low-Energy Electron Beam as a Tool for ultrashort bunch length measurement in circular machines

    CERN Document Server

    Nikiforov, D A; Malyutin, D; Matveenko, A; Rusinov, K; Starostenko, A A

    2017-01-01

    A new diagnostic device designed for non-destructive ultrashort bunch length measurement is described. The operating principle of the device and the measuring technique are described. The possible scheme of arrangement of the device elements are described. The results of simulations of EBP application for different beams under investigation are presented. The quality requirements of the low energy testing beam are considered and resolving detector ability is determined.

  17. Intensity and bunch length measurement for lepton beam in the injection lines of the SPS and LEP

    CERN Document Server

    Boccard, C; Papis, J P; Vos, L

    1995-01-01

    We describe a system which is used operationally to measure the absolute intensity of single lepton bunches in a beam transfer line. It is based on the detailed knowledge of every single item of a complex measuring chain that comprises a beam coupler on one end and an acquisition system on the other end. This knowledge can be acquired by a well tested theoretical model and careful measurement of the transfer function of each processing module. A precision better than 3 % can be obtained and no external calibration is required. A value for the bunch length can be deduced from a spectral intensity measurement at two well chosen frequencies.

  18. Length and volume of morphologically normal kidneys in Korean Children: Ultrasound measurement and estimation using body size

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jun Hwee; Kim, Myung Joon; Lim, Sok Hwan; Lee, Mi Jung [Dept. of Radiology and Research Institute of Radiological Science, Severance Children' s Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); Kim, Ji Eun [Biostatistics Collaboration Unit, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2013-08-15

    To evaluate the relationship between anthropometric measurements and renal length and volume measured with ultrasound in Korean children who have morphologically normal kidneys, and to create simple equations to estimate the renal sizes using the anthropometric measurements. We examined 794 Korean children under 18 years of age including a total of 394 boys and 400 girls without renal problems. The maximum renal length (L) (cm), orthogonal anterior-posterior diameter (D) (cm) and width (W) (cm) of each kidney were measured on ultrasound. Kidney volume was calculated as 0.523 x L x D x W (cm{sup 3}). Anthropometric indices including height (cm), weight (kg) and body mass index (m{sup 2}/kg) were collected through a medical record review. We used linear regression analysis to create simple equations to estimate the renal length and the volume with those anthropometric indices that were mostly correlated with the US-measured renal sizes. Renal length showed the strongest significant correlation with patient height (R2, 0.874 and 0.875 for the right and left kidneys, respectively, p < 0.001). Renal volume showed the strongest significant correlation with patient weight (R2, 0.842 and 0.854 for the right and left kidneys, respectively, p < 0.001). The following equations were developed to describe these relationships with an estimated 95% range of renal length and volume (R2, 0.826-0.884, p < 0.001): renal length = 2.383 + 0.045 x Height (± 1.135) and = 2.374 + 0.047 x Height (± 1.173) for the right and left kidneys, respectively; and renal volume 7.941 + 1.246 x Weight (± 15.920) and = 7.303 + 1.532 x Weight (± 18.704) for the right and left kidneys, respectively. Scatter plots between height and renal length and between weight and renal volume have been established from Korean children and simple equations between them have been developed for use in clinical practice.

  19. Length and volume of morphologically normal kidneys in Korean Children: Ultrasound measurement and estimation using body size

    International Nuclear Information System (INIS)

    Kim, Jun Hwee; Kim, Myung Joon; Lim, Sok Hwan; Lee, Mi Jung; Kim, Ji Eun

    2013-01-01

    To evaluate the relationship between anthropometric measurements and renal length and volume measured with ultrasound in Korean children who have morphologically normal kidneys, and to create simple equations to estimate the renal sizes using the anthropometric measurements. We examined 794 Korean children under 18 years of age including a total of 394 boys and 400 girls without renal problems. The maximum renal length (L) (cm), orthogonal anterior-posterior diameter (D) (cm) and width (W) (cm) of each kidney were measured on ultrasound. Kidney volume was calculated as 0.523 x L x D x W (cm 3 ). Anthropometric indices including height (cm), weight (kg) and body mass index (m 2 /kg) were collected through a medical record review. We used linear regression analysis to create simple equations to estimate the renal length and the volume with those anthropometric indices that were mostly correlated with the US-measured renal sizes. Renal length showed the strongest significant correlation with patient height (R2, 0.874 and 0.875 for the right and left kidneys, respectively, p < 0.001). Renal volume showed the strongest significant correlation with patient weight (R2, 0.842 and 0.854 for the right and left kidneys, respectively, p < 0.001). The following equations were developed to describe these relationships with an estimated 95% range of renal length and volume (R2, 0.826-0.884, p < 0.001): renal length = 2.383 + 0.045 x Height (± 1.135) and = 2.374 + 0.047 x Height (± 1.173) for the right and left kidneys, respectively; and renal volume 7.941 + 1.246 x Weight (± 15.920) and = 7.303 + 1.532 x Weight (± 18.704) for the right and left kidneys, respectively. Scatter plots between height and renal length and between weight and renal volume have been established from Korean children and simple equations between them have been developed for use in clinical practice.

  20. Test-retest reliability of stride time variability while dual tasking in healthy and demented adults with frontotemporal degeneration

    Directory of Open Access Journals (Sweden)

    Herrmann Francois R

    2011-07-01

    Full Text Available Abstract Background Although test-retest reliability of mean values of spatio-temporal gait parameters has been assessed for reliability while walking alone (i.e., single tasking, little is known about the test-retest reliability of stride time variability (STV while performing an attention demanding-task (i.e., dual tasking. The objective of this study was to examine immediate test-retest reliability of STV while single and dual tasking in cognitively healthy older individuals (CHI and in demented patients with frontotemporal degeneration (FTD. Methods Based on a cross-sectional design, 69 community-dwelling CHI (mean age 75.5 ± 4.3; 43.5% women and 14 demented patients with FTD (mean age 65.7 ± 9.8 years; 6.7% women walked alone (without performing an additional task; i.e., single tasking and while counting backward (CB aloud starting from 50 (i.e., dual tasking. Each subject completed two trials for all the testing conditions. The mean value and the coefficient of variation (CoV of stride time while walking alone and while CB at self-selected walking speed were measured using GAITRite® and SMTEC® footswitch systems. Results ICC of mean value in CHI under both walking conditions were higher than ICC of demented patients with FTD and indicated perfect reliability (ICC > 0.80. Reliability of mean value was better while single tasking than dual tasking in CHI (ICC = 0.96 under single-task and ICC = 0.86 under dual-task, whereas it was the opposite in demented patients (ICC = 0.65 under single-task and ICC = 0.81 under dual-task. ICC of CoV was slight to poor whatever the group of participants and the walking condition (ICC Conclusions The immediate test-retest reliability of the mean value of stride time in single and dual tasking was good in older CHI as well as in demented patients with FTD. In contrast, the variability of stride time was low in both groups of participants.

  1. Measurement of the magneto-optical correlation length in turbid media

    Science.gov (United States)

    Lenke, Ralf; Eisenmann, Christoph; Reinke, Daniel; Maret, Georg

    2002-11-01

    In multiple light scattering media, magnetic field induced circular birefringence (Faraday effect) influences interference effects such as speckle pattern or coherent backscattering. It was predicted that in the diffusive regime the relevant correlation length with respect to the Faraday rotation l*F differs, in general, from the transport mean free path l*. We have experimentally verified the prediction that the ratio l*F/l* equals 2 for Rayleigh scattering and decreases to 1 with increasing scatterer size. We also discuss the influence of the structure factor on l*F.

  2. Measurement of the Rayleigh scattering length in liquid scintillators for JUNO

    Energy Technology Data Exchange (ETDEWEB)

    Hackspacher, Paul [Johannes Gutenberg-Universitaet Mainz, PRISMA Excellence Cluster (Germany); Collaboration: JUNO-Collaboration

    2016-07-01

    In liquid scintillator neutrino detectors such as the upcoming Jiangmen Underground Neutrino Observatory (JUNO), neutrino interactions are being detected by means of inverse beta decay and analysis of the resulting luminescent light. In order to reliably reconstruct these events from photomultiplier signals, the scattering properties of the detector materials need to be sufficiently well known. In the LAB-based liquid scintillator that has been proposed for JUNO, the primary contribution to the scattering process comes from Rayleigh scattering. The characteristic Rayleigh scattering length can be experimentally obtained in an optical laboratory setup. This talk presents the approach, the current status and the future plans of the experiment.

  3. How Does Definition of Minimum Break Length Affect Objective Measures of Sitting Outcomes Among Office Workers?

    DEFF Research Database (Denmark)

    Kloster, Stine; Danquah, Ida Høgstedt; Holtermann, Andreas

    2017-01-01

    BACKGROUND: Harmful health effects associated with sedentary behaviour may be attenuated by breaking up long periods of sitting by standing or walking. However, studies assess interruptions in sitting time differently, making comparisons between studies difficult. It has not previously been...... described how the definition of minimum break duration affects sitting outcomes. Therefore, the aim was to address how definitions of break length affect total sitting time, number of sit-to-stand transitions, prolonged sitting periods and time accumulated in prolonged sitting periods among office workers...

  4. Coupling of relative intensity noise and pathlength noise to the length measurement in the optical metrology system of LISA Pathfinder

    Science.gov (United States)

    Wittchen, Andreas; the LPF Collaboration

    2017-05-01

    LISA Pathfinder is a technology demonstration mission for the space-based gravitational wave observatory, LISA. It demonstrated that the performance requirements for the interferometric measurement of two test masses in free fall can be met. An important part of the data analysis is to identify the limiting noise sources. [1] This measurement is performed with heterodyne interferometry. The performance of this optical metrology system (OMS) at high frequencies is limited by sensing noise. One such noise source is Relative Intensity Noise (RIN). RIN is a property of the laser, and the photodiode current generated by the interferometer signal contains frequency dependant RIN. From this electric signal the phasemeter calculates the phase change and laser power, and the coupling of RIN into the measurement signal depends on the noise frequency. RIN at DC, at the heterodyne frequency and at two times the heterodyne frequency couples into the phase. Another important noise at high frequencies is path length noise. To reduce the impact this noise is suppressed with a control loop. Path length noise not suppressed will couple directly into the length measurement. The subtraction techniques of both noise sources depend on the phase difference between the reference signal and the measurement signal, and thus on the test mass position. During normal operations we position the test mass at the interferometric zero, which is optimal for noise subtraction purposes. This paper will show results from an in-flight experiment where the test mass position was changed to make the position dependant noise visible.

  5. Correlation of intra-articular osseous measurements with posterior cruciate ligament length on MRI scans.

    LENUS (Irish Health Repository)

    Orakzai, S H

    2010-01-01

    Six patients with a clinical diagnosis of chronic posterior cruciate ligament (PCL) rupture, based on a positive posterior drawer test, had a normal appearance of the PCL on an MRI scan. It is postulated that the PCL had been ruptured but healed in a lengthened state. 12 volunteers with no history of knee trauma underwent an MRI scan of the knee. In this control group (n = 12), there was a close correlation between the lateral femoral condylar width in the sagittal plane and the PCL length, with a ratio of 2:1 (95% confidence interval (CI) = 1.817-2.095). In the clinically abnormal group (n = 6), the ratio was 1.49:1 (95% CI = 1.206-1.782) (p< 0.0005). In conclusion, the ratio of the lateral femoral condylar width in the sagittal plane to the PCL length is a useful index for diagnosing PCL attenuation and lengthening in the presence of a normal morphological MR appearance.

  6. Walking speed-related changes in stride time variability: effects of decreased speed

    Directory of Open Access Journals (Sweden)

    Dubost Veronique

    2009-08-01

    Full Text Available Abstract Background Conflicting results have been reported regarding the relationship between stride time variability (STV and walking speed. While some studies failed to establish any relationship, others reported either a linear or a non-linear relationship. We therefore sought to determine the extent to which decrease in self-selected walking speed influenced STV among healthy young adults. Methods The mean value, the standard deviation and the coefficient of variation of stride time, as well as the mean value of stride velocity were recorded while steady-state walking using the GAITRite® system in 29 healthy young adults who walked consecutively at 88%, 79%, 71%, 64%, 58%, 53%, 46% and 39% of their preferred walking speed. Results The decrease in stride velocity increased significantly mean values, SD and CoV of stride time (p Conclusion The results support the assumption that gait variability increases while walking speed decreases and, thus, gait might be more unstable when healthy subjects walk slower compared with their preferred walking speed. Furthermore, these results highlight that a decrease in walking speed can be a potential confounder while evaluating STV.

  7. Project Stride: An Equine-Assisted Intervention to Reduce Symptoms of Social Anxiety in Young Women.

    Science.gov (United States)

    Alfonso, Sarah V; Alfonso, Lauren A; Llabre, Maria M; Fernandez, M Isabel

    2015-01-01

    Although there is evidence supporting the use of equine-assisted activities to treat mental disorders, its efficacy in reducing signs and symptoms of social anxiety in young women has not been examined. We developed and pilot tested Project Stride, a brief, six-session intervention combining equine-assisted activities and cognitive-behavioral strategies to reduce symptoms of social anxiety. A total of 12 women, 18-29 years of age, were randomly assigned to Project Stride or a no-treatment control. Participants completed the Liebowitz Social Anxiety Scale at baseline, immediate-post, and 6 weeks after treatment. Project Stride was highly acceptable and feasible. Compared to control participants, those in Project Stride had significantly greater reductions in social anxiety scores from baseline to immediate-post [decrease of 24.8 points; t (9) = 3.40, P = .008)] and from baseline to follow-up [decrease of 31.8 points; t (9) = 4.12, P = .003)]. These findings support conducting a full-scale efficacy trial of Project Stride. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Modeling the effect of probe force on length measurements on polymer parts

    DEFF Research Database (Denmark)

    Mohammadi, Ali; Sonne, Mads Rostgaard; Dalla Costa, Giuseppe

    2016-01-01

    Measurement uncertainty at micrometer level is in the future going to be very common in dimensional measurements on polymer parts. Accurate dimensional measurement of polymer parts is becoming a key and common practice in the industry, especially when micrometer tolerances are required. When cond...

  9. The Accuracy of the Digital imaging system and the frequency dependent type apex locator in root canal length measurement

    International Nuclear Information System (INIS)

    Lee, Byoung Rib; Park, Chang Seo

    1998-01-01

    In order to achieve a successful endodontic treatment, root canals must be obturated three-dimensionally without causing any damage to apical tissues. Accurate length determination of the root canal is critical in this case. For this reason, I've used the conventional periapical radiography, Digora (digital imaging system) and Root ZX (the frequency dependent type apex locator) to measure the length of the canal and compare it with the true length obtained by cutting the tooth in half and measuring the length between the occlusal surface and the apical foramen. From the information obtained by these measurements, I was able to evaluate the accuracy and clinical usefulness of each systems, whether the thickness of files used in endodontic therapy has any effect on the measuring systems was also evaluated in an effort to simplify the treatment planning phase of endodontic treatment. 29 canals of 29 sound premolars were measured with no 15, no 20, no 25 files by 3 different dentists each using the periapical radiography, Digora and Root ZX. The measurements were then compared with the true length. The results were as follows ; 1. In comparing mean discrepancies between measurements obtained by using periapical radiography (mean error : -0.449 ± 0.444 mm), Digora (mean error : -0.417 ± 0.415 mm) and Root ZX (mean error : 0.123 ± 0.458 mm) with true length, periapical radiography and Digora system had statistically significant differences (p 0.05). 2. By subtracting values obtained by using periapical radiography, Digora and Root ZX from the true length and making a distribution table of their absolute values, the following analysis was possible. In the case of periapical film, 140 out of 261 (53.6%) were clinically acceptable satisfying the margin of error of less than 0.5 mm, 151 out of 261 (53,6%) were acceptable in the Digora system while Root ZX had 197 out of 261 (75.5%) within the limits of 0.5 mm margin of error. 3. In determining whether the thickness of

  10. Voxel effects within digital images of trabecular bone and their consequences on chord-length distribution measurements

    International Nuclear Information System (INIS)

    Rajon, D.A.; Shah, A.P.; Watchman, C.J.; Bolch, W.E.; Jokisch, D.W.; Patton, P.W.

    2002-01-01

    Chord-length distributions through the trabecular regions of the skeleton have been investigated since the early 1960s. These distributions have become important features for bone marrow dosimetry; as such, current models rely on the accuracy of their measurements. Recent techniques utilize nuclear magnetic resonance (NMR) microscopy to acquire 3D images of trabecular bone that are then used to measure 3D chord-length distributions by Monte Carlo methods. Previous studies have shown that two voxel effects largely affect the acquisition of these distributions within digital images. One is particularly pertinent as it dramatically changes the shape of the distribution and reduces its mean. An attempt was made to reduce this undesirable effect and good results were obtained for a single-sphere model using minimum acceptable chord (MAC) methods (Jokisch et al 2001 Med. Phys. 28 1493-504). The goal of the present work is to extend the study of these methods to more general models in order to better quantify their consequences. First, a mathematical model of a trabecular bone sample was used to test the usefulness of the MAC methods. The results showed that these methods were not efficient for this simulated bone model. These methods were further tested on a single voxelized sphere over a large range of voxel sizes. The results showed that the MAC methods are voxel-size dependent and overestimate the mean chord length for typical resolutions used with NMR microscopy. The study further suggests that bone and marrow chord-length distributions currently utilized in skeletal dosimetry models are most likely affected by voxel effects that yield values of mean chord length lower than their true values. (author)

  11. Predicted singers' vocal fold lengths and voice classification-a study of x-ray morphological measures.

    Science.gov (United States)

    Roers, Friederike; Mürbe, Dirk; Sundberg, Johan

    2009-07-01

    Students admitted to the solo singing education at the University of Music Dresden, Germany have been submitted to a detailed physical examination of a variety of factors with relevance to voice function since 1959. In the years 1959-1991, this scheme of examinations included X-ray profiles of the singers' vocal tracts. This material of 132 X-rays of voice professionals was used to investigate different laryngeal morphological measures and their relation to vocal fold length. Further, the study aimed to investigate if there are consistent anatomical differences between singers of different voice classifications. The study design used was a retrospective analysis. Vocal fold length could be measured in 29 of these singer subjects directly. These data showed a strong correlation with the anterior-posterior diameter of the subglottis and the trachea as well as with the distance from the anterior contour of the thyroid cartilage to the anterior contour of the spine. These relations were used in an attempt to predict the 132 singers' vocal fold lengths. The results revealed a clear covariation between predicted vocal fold length and voice classification. Anterior-posterior subglottic-tracheal diameter yielded mean vocal fold lengths of 14.9, 16.0, 16.6, 18.4, 19.5, and 20.9mm for sopranos, mezzo-sopranos, altos, tenors, baritones, and basses, respectively. The data support the assumption that there are consistent anatomical laryngeal differences between singers of different voice classifications, which are of relevance to pitch range and timbre of the voice.

  12. Possible biomechanical origins of the long-range correlations in stride intervals of walking

    Science.gov (United States)

    Gates, Deanna H.; Su, Jimmy L.; Dingwell, Jonathan B.

    2007-07-01

    When humans walk, the time duration of each stride varies from one stride to the next. These temporal fluctuations exhibit long-range correlations. It has been suggested that these correlations stem from higher nervous system centers in the brain that control gait cycle timing. Existing proposed models of this phenomenon have focused on neurophysiological mechanisms that might give rise to these long-range correlations, and generally ignored potential alternative mechanical explanations. We hypothesized that a simple mechanical system could also generate similar long-range correlations in stride times. We modified a very simple passive dynamic model of bipedal walking to incorporate forward propulsion through an impulsive force applied to the trailing leg at each push-off. Push-off forces were varied from step to step by incorporating both “sensory” and “motor” noise terms that were regulated by a simple proportional feedback controller. We generated 400 simulations of walking, with different combinations of sensory noise, motor noise, and feedback gain. The stride time data from each simulation were analyzed using detrended fluctuation analysis to compute a scaling exponent, α. This exponent quantified how each stride interval was correlated with previous and subsequent stride intervals over different time scales. For different variations of the noise terms and feedback gain, we obtained short-range correlations (α1.0). Our results indicate that a simple biomechanical model of walking can generate long-range correlations and thus perhaps these correlations are not a complex result of higher level neuronal control, as has been previously suggested.

  13. Q-FISH measurement of hepatocyte telomere lengths in donor liver and graft after pediatric living-donor liver transplantation: donor age affects telomere length sustainability.

    Directory of Open Access Journals (Sweden)

    Youichi Kawano

    Full Text Available Along with the increasing need for living-donor liver transplantation (LDLT, the issue of organ shortage has become a serious problem. Therefore, the use of organs from elderly donors has been increasing. While the short-term results of LDLT have greatly improved, problems affecting the long-term outcome of transplant patients remain unsolved. Furthermore, since contradictory data have been reported with regard to the relationship between donor age and LT/LDLT outcome, the question of whether the use of elderly donors influences the long-term outcome of a graft after LT/LDLT remains unsettled. To address whether hepatocyte telomere length reflects the outcome of LDLT, we analyzed the telomere lengths of hepatocytes in informative biopsy samples from 12 paired donors and recipients (grafts of pediatric LDLT more than 5 years after adult-to-child LDLT because of primary biliary atresia, using quantitative fluorescence in situ hybridization (Q-FISH. The telomere lengths in the paired samples showed a robust relationship between the donor and grafted hepatocytes (r = 0.765, p = 0.0038, demonstrating the feasibility of our Q-FISH method for cell-specific evaluation. While 8 pairs showed no significant difference between the telomere lengths for the donor and the recipient, the other 4 pairs showed significantly shorter telomeres in the recipient than in the donor. Multiple regression analysis revealed that the donors in the latter group were older than those in the former (p = 0.001. Despite the small number of subjects, this pilot study indicates that donor age is a crucial factor affecting telomere length sustainability in hepatocytes after pediatric LDLT, and that the telomeres in grafted livers may be elongated somewhat longer when the grafts are immunologically well controlled.

  14. Interpretation of Core Length in Shear Coaxial Rocket Injectors from X-ray Radiography Measurements

    Science.gov (United States)

    2014-06-01

    interrogating the near field of a number of dense sprays including diesel injectors , aerated liquid jets, solid-cone sprays, impinging-jet sprays and gas...Measurements of Mass Distributions in the Near- Nozzle Region of Sprays form Standard Multi-hole Common-rail Diesel Injection Systems,” 11th Triennial...Shear Coaxial Rocket Injectors from X-ray Radiography Measurements 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT

  15. Measurements of neutron spectrum from stopping-length target irradiated by several tens-MeV/u particles

    Energy Technology Data Exchange (ETDEWEB)

    Meigo, Shin-ichiro; Takada, Hiroshi; Nakashima, Hiroshi; Sasa, Toshinobu [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Tanaka, Susumu; Shin, Kazuo; Ono, Shinji

    1997-03-01

    Using a Time-of-Flight technique, we have measured neutron spectra from stopping-length targets bombarded with 68-MeV protons and 100-MeV {alpha}-particles. The measured spectra were used to validate the results calculated by the Quantum Molecular Dynamics (QMD) plus Statistical Decay Model (SDM). The results of QMD plus SDM code agreed fairly well with the experimental data for the light target. On the other hand, the QMD plus SDM gives a larger value than the experimental for the heavy target. (author)

  16. Path-length-resolved measurements of multiple scattered photons in static and dynamic turbid media using phase-modulated low-coherence interferometry

    NARCIS (Netherlands)

    Varghese, Babu; Rajan, Vinayakrishnan; van Leeuwen, Ton G.; Steenbergen, Wiendelt

    2007-01-01

    In optical Doppler measurements, the path length of the light is unknown. To facilitate quantitative measurements, we develop a phase-modulated Mach-Zehnder interferometer with separate fibers for illumination and detection. With this setup, path-length-resolved dynamic light scattering measurements

  17. STRIDE II: A Water Strider-inspired Miniature Robot with Circular Footpads

    Directory of Open Access Journals (Sweden)

    Onur Ozcan

    2014-06-01

    Full Text Available Water strider insects have attracted the attention of many researchers due to their power-efficient and agile water surface locomotion. This study proposes a new water strider insect-inspired robot, called STRIDE II, which uses new circular footpads for high lift, stability and payload capability, and a new elliptical leg rotation mechanism for more efficient water surface propulsion. Using the advantage of scaling effects on surface tension versus buoyancy, similar to water strider insects, this robot uses the repulsive surface tension force on its footpads as the dominant lift principle instead of creating buoyancy by using very skinny (1 mm diameter circular footpads coated with a superhydrophobic material. The robot and the insect propel quickly and power efficiently on the water surface by the sculling motion of their two side-legs, which never break the water surface completely. This paper proposes models for the lift, drag and propulsion forces and the energy efficiency of the proposed legged robot, and experiments are conducted to verify these models. After optimizing the robot design using the lift models, a maximum lift capacity of 55 grams is achieved using 12 footpads with a 4.2 cm outer diameter, while the robot itself weighs 21.75 grams. For this robot, a propulsion efficiency of 22.3% was measured. The maximum forward and turning speeds of the robot were measured as 71.5 mm/sec and 0.21 rad/sec, respectively. These water strider robots could be used in water surface monitoring, cleaning and analysis in lakes, dams, rivers and the sea.

  18. Electron critical gradient scale length measurements of ICRF heated L-mode plasmas at Alcator C-Mod tokamak

    Science.gov (United States)

    Houshmandyar, S.; Hatch, D. R.; Horton, C. W.; Liao, K. T.; Phillips, P. E.; Rowan, W. L.; Zhao, B.; Cao, N. M.; Ernst, D. R.; Greenwald, M.; Howard, N. T.; Hubbard, A. E.; Hughes, J. W.; Rice, J. E.

    2018-04-01

    A profile for the critical gradient scale length (Lc) has been measured in L-mode discharges at the Alcator C-Mod tokamak, where electrons were heated by an ion cyclotron range of frequency through minority heating with the intention of simultaneously varying the heat flux and changing the local gradient. The electron temperature gradient scale length (LTe-1 = |∇Te|/Te) profile was measured via the BT-jog technique [Houshmandyar et al., Rev. Sci. Instrum. 87, 11E101 (2016)] and it was compared with electron heat flux from power balance (TRANSP) analysis. The Te profiles were found to be very stiff and already above the critical values, however, the stiffness was found to be reduced near the q = 3/2 surface. The measured Lc profile is in agreement with electron temperature gradient (ETG) models which predict the dependence of Lc-1 on local Zeff, Te/Ti, and the ratio of the magnetic shear to the safety factor. The results from linear Gene gyrokinetic simulations suggest ETG to be the dominant mode of turbulence in the electron scale (k⊥ρs > 1), and ion temperature gradient/trapped electron mode modes in the ion scale (k⊥ρs < 1). The measured Lc profile is in agreement with the profile of ETG critical gradients deduced from Gene simulations.

  19. Noise Suppression on the Tunable Laser for Precise Cavity Length Displacement Measurement

    Czech Academy of Sciences Publication Activity Database

    Šmíd, Radek; Čížek, Martin; Mikel, Břetislav; Hrabina, Jan; Lazar, Josef; Číp, Ondřej

    2016-01-01

    Roč. 16, č. 9 (2016), 1428:1-11 ISSN 1424-8220 R&D Projects: GA ČR(CZ) GPP102/12/P962; GA ČR GB14-36681G; GA MŠk(CZ) LO1212; GA MŠk ED0017/01/01 Institutional support: RVO:68081731 Keywords : Fabry-Perot cavity * unbalance Michelson interferometer * noise suppression * heterodyne interferometry * displacement measurement Subject RIV: BH - Optics, Masers, Laser s Impact factor: 2.677, year: 2016

  20. An Experimental Measurement on Laminar Burning Velocities and Markstein Length of Iso-Butane-Air Mixtures at Ambient Conditions

    Directory of Open Access Journals (Sweden)

    Yousif Alaeldeen Altag

    2016-01-01

    Full Text Available In the present work, experimental investigation on laminar combustion of iso-butane-air mixtures was conducted in constant volume explosion vessel. The experiments were conducted at wide range of equivalence ratios ranging between Ф = 0.6 and 1.4 and atmospheric pressure of 0.1 MPa and ambient temperature of 303K. Using spherically expanding flame method, flame parameters including stretched, unstretched flame propagation speeds, laminar burning velocities and Markstein length were calculated. For laminar burning velocities the method of error bars of 95% confidence level was applied. In addition, values of Markstein lengths were measured in wide range of equivalence ratios to study the influence of stretch rate on flame instability and burning velocity. It was found that the stretched flame speed and laminar burning velocities increased with equivalence ratios and the peak value was obtained at equivalence ratio of Ф = 1.1. The Markstein length decreased with the increases in equivalence ratios, which indicates that the diffusion thermal flame instability increased at high equivalence ratios in richer mixture side. However, the total deviations in the laminar burning velocities have discrepancies of 1.2-2.9% for all investigated mixtures.

  1. Development of a Data Reduction Algorithm for Optical Wide Field Patrol (OWL) II: Improving Measurement of Lengths of Detected Streaks

    Science.gov (United States)

    Park, Sun-Youp; Choi, Jin; Roh, Dong-Goo; Park, Maru; Jo, Jung Hyun; Yim, Hong-Suh; Park, Young-Sik; Bae, Young-Ho; Park, Jang-Hyun; Moon, Hong-Kyu; Choi, Young-Jun; Cho, Sungki; Choi, Eun-Jung

    2016-09-01

    As described in the previous paper (Park et al. 2013), the detector subsystem of optical wide-field patrol (OWL) provides many observational data points of a single artificial satellite or space debris in the form of small streaks, using a chopper system and a time tagger. The position and the corresponding time data are matched assuming that the length of a streak on the CCD frame is proportional to the time duration of the exposure during which the chopper blades do not obscure the CCD window. In the previous study, however, the length was measured using the diagonal of the rectangle of the image area containing the streak; the results were quite ambiguous and inaccurate, allowing possible matching error of positions and time data. Furthermore, because only one (position, time) data point is created from one streak, the efficiency of the observation decreases. To define the length of a streak correctly, it is important to locate the endpoints of a streak. In this paper, a method using a differential convolution mask pattern is tested. This method can be used to obtain the positions where the pixel values are changed sharply. These endpoints can be regarded as directly detected positional data, and the number of data points is doubled by this result.

  2. The effects of social status on biological aging as measured by white-blood-cell telomere length.

    Science.gov (United States)

    Cherkas, L F; Aviv, A; Valdes, A M; Hunkin, J L; Gardner, J P; Surdulescu, G L; Kimura, M; Spector, T D

    2006-10-01

    Low socio-economic status (SES) is associated with a shortened life expectancy, but its effect on aging is unknown. The rate of white-blood-cell (WBC) telomere attrition may be a biological indicator of human aging. We tested the hypothesis that SES is associated with telomere attrition independent of known risk factors influencing the aging process. We studied 1552 female twins. A venous blood sample was taken from each twin and isolated WBCs used for extraction of DNA. Terminal restriction fragment length (TRFL) was measured. Questionnaire data were collected on occupation, education, income, smoking, exercise, height and weight. Standard multiple linear regression and multivariate analyses of variance tested for associations between SES and TRFL, adjusting for covariates. A discordant twin analysis was conducted on a subset to verify findings. WBC telomere length was highly variable but significantly shorter in lower SES groups. The mean difference in TRFL between nonmanual and manual SES groups was 163.2 base pairs (bp) of which 22.9 bp (approximately 14%) was accounted for by body mass index, smoking and exercise. Comparison of TRFL in the 17 most discordant SES twin pairs confirmed this difference. Low SES, in addition to the harmful effects of smoking, obesity and lack of exercise, appears to have an impact on telomere length.

  3. LEARNING ONE-DIGIT DECIMAL NUMBERS BY MEASUREMENT AND GAME PREDICTING LENGTH

    Directory of Open Access Journals (Sweden)

    Puji Astuti

    2014-01-01

    Full Text Available This paper aims to describe how students develop understanding of one-digit decimals. To achieve the aim, Local Instruction Theory (LIT about the process of learning decimals and the means designed to support that learning are developed. Along with this idea, the framework of Realistic Mathematics Education (RME is proposed. Based on the aim, design research methodology is used. This paper discusses learning activities of three meetings from teaching experiment of the focus group students of the fourth grade elementary school in Surabaya: SDIT Al Ghilmani. The data indicated that the learning activities promoted the students’ understanding of one-digit decimal numbers.Keyword: measurement, decimal numbers, number line DOI: http://dx.doi.org/10.22342/jme.5.1.1447.35-46

  4. Optical 'dampening' of the refractive error to axial length ratio: implications for outcome measures in myopia control studies.

    Science.gov (United States)

    Cruickshank, Fiona E; Logan, Nicola S

    2018-05-01

    To gauge the extent to which differences in the refractive error axial length relationship predicted by geometrical optics are observed in actual refractive/biometric data. This study is a retrospective analysis of existing data. Right eye refractive error [RX] and axial length [AXL] data were collected on 343 6-to-7-year-old children [mean 7.18 years (S.D. 0.35)], 294 12-to-13-year-old children [mean 13.12 years (S.D. 0.32)] and 123 young adults aged 18-to-25-years [mean 20.56 years (S.D. 1.91)]. Distance RX was measured with the Shin-Nippon NVision-K 5001 infrared open-field autorefractor. Child participants were cyclopleged prior to data collection (1% Cyclopentolate Hydrochloride). Myopia was defined as a mean spherical equivalent [MSE] ≤-0.50 D. Axial length was measured using the Zeiss IOLMaster 500. Optical modelling was based on ray tracing and manipulation of parameters of a Gullstrand reduced model eye. There was a myopic shift in mean MSE with age (6-7 years +0.87 D, 12-13 years -0.06 D and 18-25 years -1.41 D), associated with an increase in mean AXL (6-7 years 22.70 mm, 12-13 years 23.49 mm and 18-25 years 23.98 mm). There was a significant negative correlation between MSE and AXL for all age groups (all p theory predicts that there will be a reduction in the RX: AXL ratio with longer eyes. The participant data although adhering to this theory show a reduced effect, with eyes with longer axial lengths having a lower refractive error to axial length ratio than predicted by model eye calculations. We propose that in myopia control intervention studies when comparing efficacy, consideration should be given to the dampening effect seen with a longer eye. © 2018 The Authors. Ophthalmic and Physiological Optics published by John Wiley & Sons Ltd on behalf of College of Optometrists.

  5. Multiple measures of adiposity are associated with mean leukocyte telomere length in the northern Finland birth cohort 1966.

    Directory of Open Access Journals (Sweden)

    Jessica L Buxton

    Full Text Available Studies of leukocyte telomere length (LTL and adiposity have produced conflicting results, and the relationship between body mass index (BMI and telomere length throughout life remains unclear. We therefore tested association of adult LTL measured in 5,598 participants with: i childhood growth measures (BMI and age at adiposity rebound (AR; ii change in BMI from childhood to adulthood and iii adult BMI, waist-to-hip ratio (WHR, body adiposity index (BAI. Childhood BMI at AR was positively associated with LTL at 31 years in women (P = 0.041. Adult BMI and WHR in both men (P = 0.025 and P = 0.049, respectively and women (P = 0.029 and P = 0.008, respectively, and BAI in women (P = 0.021 were inversely associated with LTL at 31 years. An increase in standardised BMI between early childhood and adulthood was associated with shorter adult LTL in women (P = 0.008. We show that LTL is inversely associated with multiple measures of adiposity in both men and women. Additionally, BMI increase in women from childhood to adulthood is associated with shorter telomeres at age 31, potentially indicating accelerated biological ageing.

  6. Axial Length Variation Impacts on Superficial Retinal Vessel Density and Foveal Avascular Zone Area Measurements Using Optical Coherence Tomography Angiography.

    Science.gov (United States)

    Sampson, Danuta M; Gong, Peijun; An, Di; Menghini, Moreno; Hansen, Alex; Mackey, David A; Sampson, David D; Chen, Fred K

    2017-06-01

    To evaluate the impact of image magnification correction on superficial retinal vessel density (SRVD) and foveal avascular zone area (FAZA) measurements using optical coherence tomography angiography (OCTA). Participants with healthy retinas were recruited for ocular biometry, refraction, and RTVue XR Avanti OCTA imaging with the 3 × 3-mm protocol. The foveal and parafoveal SRVD and FAZA were quantified with custom software before and after correction for magnification error using the Littman and the modified Bennett formulae. Relative changes between corrected and uncorrected SRVD and FAZA were calculated. Forty subjects were enrolled and the median (range) age of the participants was 30 (18-74) years. The mean (range) spherical equivalent refractive error was -1.65 (-8.00 to +4.88) diopters and mean (range) axial length was 24.42 mm (21.27-28.85). Images from 13 eyes were excluded due to poor image quality leaving 67 for analysis. Relative changes in foveal and parafoveal SRVD and FAZA after correction ranged from -20% to +10%, -3% to +2%, and -20% to +51%, respectively. Image size correction in measurements of foveal SRVD and FAZA was greater than 5% in 51% and 74% of eyes, respectively. In contrast, 100% of eyes had less than 5% correction in measurements of parafoveal SRVD. Ocular biometry should be performed with OCTA to correct image magnification error induced by axial length variation. We advise caution when interpreting interocular and interindividual comparisons of SRVD and FAZA derived from OCTA without image size correction.

  7. Neutron detection efficiency determinations for the TUNL neutron-neutron and neutron-proton scattering-length measurements

    Energy Technology Data Exchange (ETDEWEB)

    Trotter, D.E. Gonzalez [Department of Physics, Duke University and Triangle Universities Nuclear Laboratory, Durham, NC 27708-0308 (United States)], E-mail: crowell@tunl.duke.edu; Meneses, F. Salinas [Department of Physics, Duke University and Triangle Universities Nuclear Laboratory, Durham, NC 27708-0308 (United States); Tornow, W. [Department of Physics, Duke University and Triangle Universities Nuclear Laboratory, Durham, NC 27708-0308 (United States)], E-mail: tornow@tunl.duke.edu; Crowell, A.S.; Howell, C.R. [Department of Physics, Duke University and Triangle Universities Nuclear Laboratory, Durham, NC 27708-0308 (United States); Schmidt, D. [Physikalisch-Technische Bundesanstalt, D-38116, Braunschweig (Germany); Walter, R.L. [Department of Physics, Duke University and Triangle Universities Nuclear Laboratory, Durham, NC 27708-0308 (United States)

    2009-02-11

    The methods employed and the results obtained from measurements and calculations of the detection efficiency for the neutron detectors used at Triangle Universities Nuclear Laboratory (TUNL) in the simultaneous determination of the {sup 1}S{sub 0} neutron-neutron and neutron-proton scattering lengths a{sub nn} and a{sub np}, respectively, are described. Typical values for the detector efficiency were 0.3. Very good agreement between the different experimental methods and between data and calculation has been obtained in the neutron energy range below E{sub n}=13MeV.

  8. Neutron detection efficiency determinations for the TUNL neutron-neutron and neutron-proton scattering-length measurements

    International Nuclear Information System (INIS)

    Trotter, D.E. Gonzalez; Meneses, F. Salinas; Tornow, W.; Crowell, A.S.; Howell, C.R.; Schmidt, D.; Walter, R.L.

    2009-01-01

    The methods employed and the results obtained from measurements and calculations of the detection efficiency for the neutron detectors used at Triangle Universities Nuclear Laboratory (TUNL) in the simultaneous determination of the 1 S 0 neutron-neutron and neutron-proton scattering lengths a nn and a np , respectively, are described. Typical values for the detector efficiency were 0.3. Very good agreement between the different experimental methods and between data and calculation has been obtained in the neutron energy range below E n =13MeV.

  9. Sizing Up the Milky Way: A Bayesian Mixture Model Meta-analysis of Photometric Scale Length Measurements

    Science.gov (United States)

    Licquia, Timothy C.; Newman, Jeffrey A.

    2016-11-01

    The exponential scale length (L d ) of the Milky Way’s (MW’s) disk is a critical parameter for describing the global physical size of our Galaxy, important both for interpreting other Galactic measurements and helping us to understand how our Galaxy fits into extragalactic contexts. Unfortunately, current estimates span a wide range of values and are often statistically incompatible with one another. Here, we perform a Bayesian meta-analysis to determine an improved, aggregate estimate for L d , utilizing a mixture-model approach to account for the possibility that any one measurement has not properly accounted for all statistical or systematic errors. Within this machinery, we explore a variety of ways of modeling the nature of problematic measurements, and then employ a Bayesian model averaging technique to derive net posterior distributions that incorporate any model-selection uncertainty. Our meta-analysis combines 29 different (15 visible and 14 infrared) photometric measurements of L d available in the literature; these involve a broad assortment of observational data sets, MW models and assumptions, and methodologies, all tabulated herein. Analyzing the visible and infrared measurements separately yields estimates for L d of {2.71}-0.20+0.22 kpc and {2.51}-0.13+0.15 kpc, respectively, whereas considering them all combined yields 2.64 ± 0.13 kpc. The ratio between the visible and infrared scale lengths determined here is very similar to that measured in external spiral galaxies. We use these results to update the model of the Galactic disk from our previous work, constraining its stellar mass to be {4.8}-1.1+1.5× {10}10 M ⊙, and the MW’s total stellar mass to be {5.7}-1.1+1.5× {10}10 M ⊙.

  10. A New Measurement of the 1S0 Neutron-Neutron Scattering Length using the Neutron-Proton Scattering Length as a Standard

    OpenAIRE

    Trotter, D. E. Gonzalez; Salinas, F.; Chen, Q.; Crowell, A. S.; Gloeckle, W.; Howell, C. R.; Roper, C. D.; Schmidt, D.; Slaus, I.; Tang, H.; Tornow, W.; Walter, R. L.; Witala, H.; Zhou, Z.

    1999-01-01

    The present paper reports high-accuracy cross-section data for the 2H(n,nnp) reaction in the neutron-proton (np) and neutron-neutron (nn) final-state-interaction (FSI) regions at an incident mean neutron energy of 13.0 MeV. These data were analyzed with rigorous three-nucleon calculations to determine the 1S0 np and nn scattering lengths, a_np and a_nn. Our results are a_nn = -18.7 +/- 0.6 fm and a_np = -23.5 +/- 0.8 fm. Since our value for a_np obtained from neutron-deuteron (nd) breakup agr...

  11. Reproducibility of Macular Pigment Optical Density Measurement by Two-wave Length Auto-fluorescence in a Clinical Setting

    Science.gov (United States)

    You, Qi-Sheng; Bartsch, Dirk-Uwe G.; Espina, Mark; Alam, Mostafa; Camacho, Natalia; Mendoza, Nadia; Freeman, William

    2015-01-01

    Purpose Macular pigment, composed of lutein, zeaxanthin, and meso-zeaxanthin, is postulated to protect against age-related macular degeneration (AMD), likely due to filtering blue light and its antioxidant properties. Macular pigment optical density (MPOD) is reported to be associated with macular function evaluated by visual acuity and multifocal electroretinogram. Given the importance of macular pigment, reliable and accurate measurement methods are important. The main purpose of current study is to determine the reproducibility of MPOD measurement by two-wave length auto-fluorescence method using scanning laser ophthalmoscopy. Methods Sixty eight eyes of 39 persons were enrolled in the study, including 11 normal eyes, 16 eyes with wet AMD, 16 eyes with dry AMD, 11 eyes with macular edema due to diabetic mellitus, branch retinal vein occlusion or macular telangiectasia and 14 eyes with tractional maculopathy including vitreomacular traction, epiretinal membrane or macular hole. MPOD was measured with a two-wavelength (488 and 514 nm) auto-fluorescence method with the Spectralis HRA+OCT after pupil dilation. The measurement was repeated for each eye 10 minutes later. The Analysis of variance (ANOVA) and Bland-Altman plot were used to assess the reproducibility between the two measurements. Results The mean MPOD at eccentricities of 1° and 2° was 0.36±0.17 (range: 0.04–0.69) and 0.15±0.08(range: −0.03, 0.35) for the first measurement and 0.35±0.17 (range: 0.02, 0.68) and 0.15±0.08 (range: −0.01, 0.33) for the second measurement respectively. The difference between the two measurements was not statistically significant, and the Bland-Altman plot showed 7.4% and 5.9% points outside the 95% limits of agreement, indicating an overall excellent reproducibility. Similarly, there is no significant difference between the first and second measurements of MPOD volume within eccentricities of 1°, 2° and 6° radius, and the Bland-Altman plot showed 8.8%, 2.9% and

  12. Precise NMR measurement and stabilization system of magnetic field of a superconducting 7 T wave length shifter

    CERN Document Server

    Borovikov, V M; Karpov, G V; Korshunov, D A; Kuper, E A; Kuzin, M V; Mamkin, V R; Medvedko, A S; Mezentsev, N A; Repkov, V V; Shkaruba, V A; Shubin, E I; Veremeenko, V F

    2001-01-01

    The system of measurement and stabilization of the magnetic field in the superconducting 7 T wave length shifter (WLS), designed at Budker Institute of Nuclear Physics are described. The measurements are performed by nuclear magnetic resonance (NMR) magnetometer at two points of the WLS magnetic field. Stabilization of the field is provided by the current pumping system. The stabilization system is based on precise NMR measurement of magnetic field as a feedback signal for computer code which control currents inside the superconducting coils. The problem of the magnetic field measurements with NMR method consists in wide spread of field in the measured area (up to 50 Gs/mm), wide temperature range of WLS operating, small space for probe and influence of iron hysteresis. Special solid-state probes were designed to satisfy this requirements. The accuracy of magnetic field measurements at probe locations is not worse than 20 ppm. For the WLS field of 7 T the reproducibility of the magnetic field of 30 ppm has be...

  13. Measurement of the penetration depth and coherence length of MgB2 in all directions using transmission electron microscopy

    DEFF Research Database (Denmark)

    Loudon, J. C.; Yazdi, Sadegh; Kasama, Takeshi

    2015-01-01

    We demonstrate that images of flux vortices in a superconductor taken with a transmission electron microscope can be used to measure the penetration depth and coherence length in all directions at the same temperature and magnetic field. This is particularly useful for MgB2, where these quantities...... vary with the applied magnetic field and values are difficult to obtain at low field or in the c direction. We obtained images of flux vortices from a MgB2 single crystal cut in the ac plane by focused ion beam milling and tilted to 45 degrees. with respect to the electron beam about...... the crystallographic a axis. A new method was developed to simulate these images that accounted for vortices with a nonzero core in a thin, anisotropic superconductor and a simplex algorithm was used to make a quantitative comparison between the images and simulations to measure the penetration depths and coherence...

  14. The accuracy of three-dimensional fused deposition modeling (FDM) compared with three-dimensional CT-Scans on the measurement of the mandibular ramus vertical length, gonion-menton length, and gonial angle

    Science.gov (United States)

    Savitri, I. T.; Badri, C.; Sulistyani, L. D.

    2017-08-01

    Presurgical treatment planning plays an important role in the reconstruction and correction of defects in the craniomaxillofacial region. The advance of solid freeform fabrication techniques has significantly improved the process of preparing a biomodel using computer-aided design and data from medical imaging. Many factors are implicated in the accuracy of the 3D model. To determine the accuracy of three-dimensional fused deposition modeling (FDM) models compared with three-dimensional CT scans in the measurement of the mandibular ramus vertical length, gonion-menton length, and gonial angle. Eight 3D models were produced from the CT scan data (DICOM file) of eight patients at the Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, University of Indonesia, Cipto Mangunkusumo Hospital. Three measurements were done three times by two examiners. The measurements of the 3D CT scans were made using OsiriX software, while the measurements of the 3D models were made using a digital caliper and goniometry. The measurement results were then compared. There is no significant difference between the measurements of the mandibular ramus vertical length, gonion-menton length, and gonial angle using 3D CT scans and FDM 3D models. FDM 3D models are considered accurate and are acceptable for clinical applications in dental and craniomaxillofacial surgery.

  15. Direct comparison of flow-FISH and qPCR as diagnostic tests for telomere length measurement in humans.

    Directory of Open Access Journals (Sweden)

    Fernanda Gutierrez-Rodrigues

    Full Text Available Telomere length measurement is an essential test for the diagnosis of telomeropathies, which are caused by excessive telomere erosion. Commonly used methods are terminal restriction fragment (TRF analysis by Southern blot, fluorescence in situ hybridization coupled with flow cytometry (flow-FISH, and quantitative PCR (qPCR. Although these methods have been used in the clinic, they have not been comprehensively compared. Here, we directly compared the performance of flow-FISH and qPCR to measure leukocytes' telomere length of healthy individuals and patients evaluated for telomeropathies, using TRF as standard. TRF and flow-FISH showed good agreement and correlation in the analysis of healthy subjects (R(2 = 0.60; p<0.0001 and patients (R(2 = 0.51; p<0.0001. In contrast, the comparison between TRF and qPCR yielded modest correlation for the analysis of samples of healthy individuals (R(2 = 0.35; p<0.0001 and low correlation for patients (R(2 = 0.20; p = 0.001; Bland-Altman analysis showed poor agreement between the two methods for both patients and controls. Quantitative PCR and flow-FISH modestly correlated in the analysis of healthy individuals (R(2 = 0.33; p<0.0001 and did not correlate in the comparison of patients' samples (R(2 = 0.1, p = 0.08. Intra-assay coefficient of variation (CV was similar for flow-FISH (10.8 ± 7.1% and qPCR (9.5 ± 7.4%; p = 0.35, but the inter-assay CV was lower for flow-FISH (9.6 ± 7.6% vs. 16 ± 19.5%; p = 0.02. Bland-Altman analysis indicated that flow-FISH was more precise and reproducible than qPCR. Flow-FISH and qPCR were sensitive (both 100% and specific (93% and 89%, respectively to distinguish very short telomeres. However, qPCR sensitivity (40% and specificity (63% to detect telomeres below the tenth percentile were lower compared to flow-FISH (80% sensitivity and 85% specificity. In the clinical setting, flow-FISH was more accurate, reproducible, sensitive, and specific in the measurement of human

  16. Windowing UWB microwave, mm-wave multi-port S-parameter measurements using open-ended excess electrical length

    Directory of Open Access Journals (Sweden)

    Gholamreza Askari

    2017-05-01

    Full Text Available Multi-port measurements are a big challenge in circuits' verification, especially when the frequency increases. This study presents a new technique for measuring S-parameters of multi-port ultra-wideband (UWB microwave and mm-wave circuits. The concepts are based on direct or indirect applying modulated UWB impulse radio in desired bandwidth to the one port of the modified multi-port circuit and gathering the reflected signal in the same port and the output signal in the second port in time domain, and the other ports are left opened with a special designed added electrical length. Then by applying intelligent windowing in time domain to the gathering data, and using fast Fourier transform, the desired S-parameters are extracted. Validation of this technique is verified by design and fabrication of a three-port UWB Wilkinson power divider in 22–30 GHz. The simulation and measurement results of the reflection and transmission S-parameters by using this new technique are very close to those are extracted with the conventional vector network analysers S-parameters measurements and show the ability and the accuracy of this technique.

  17. Cicero's de legibus and Martin Luther King, Jr.’s Stride toward freedom

    Directory of Open Access Journals (Sweden)

    Boleslav s. Povšič

    1979-12-01

    Full Text Available He who reads carefully Cicero'sDe Legibus and Martin Luther King, Jr.'s Stride Toward Freedom is surprised to find, mutatis mutandis, on how many points these two great men agree. The historical circumstances are different, but the essential ideas are very similar. The purpose of this paper is to show on what precisely they agree and on what they differ.

  18. Estimating age from recapture data: integrating incremental growth measures with ancillary data to infer age-at-length

    Science.gov (United States)

    Eaton, Mitchell J.; Link, William A.

    2011-01-01

    Estimating the age of individuals in wild populations can be of fundamental importance for answering ecological questions, modeling population demographics, and managing exploited or threatened species. Significant effort has been devoted to determining age through the use of growth annuli, secondary physical characteristics related to age, and growth models. Many species, however, either do not exhibit physical characteristics useful for independent age validation or are too rare to justify sacrificing a large number of individuals to establish the relationship between size and age. Length-at-age models are well represented in the fisheries and other wildlife management literature. Many of these models overlook variation in growth rates of individuals and consider growth parameters as population parameters. More recent models have taken advantage of hierarchical structuring of parameters and Bayesian inference methods to allow for variation among individuals as functions of environmental covariates or individual-specific random effects. Here, we describe hierarchical models in which growth curves vary as individual-specific stochastic processes, and we show how these models can be fit using capture–recapture data for animals of unknown age along with data for animals of known age. We combine these independent data sources in a Bayesian analysis, distinguishing natural variation (among and within individuals) from measurement error. We illustrate using data for African dwarf crocodiles, comparing von Bertalanffy and logistic growth models. The analysis provides the means of predicting crocodile age, given a single measurement of head length. The von Bertalanffy was much better supported than the logistic growth model and predicted that dwarf crocodiles grow from 19.4 cm total length at birth to 32.9 cm in the first year and 45.3 cm by the end of their second year. Based on the minimum size of females observed with hatchlings, reproductive maturity was estimated

  19. Measurement of the mass of the top quark using the transverse decay length and lepton transverse momentum techniques

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Christian

    2014-05-02

    A measurement of the mass of the top quark using the transverse momentum of the lepton and decay length of the B-Hadron has been presented. The result is m{sub Top}=(170.4±1.1{sub stat.}±2.3{sub syst.}) GeV. This is compatible with previous measurements of the mass of the top quark, done by either the ATLAS collaboration or other experiments. The total uncertainty on the result of this analysis, Δ{sup total}m{sub Top}=2.6 GeV is larger than results by other measurements. However, with an jet energy scale uncertainty of only Δ{sup Jes}m{sub Top}=0.3 GeV it has one of the smallest uncertainties caused by this source. In a combination of results this will help reducing the total uncertainty on the mass of the top quark. The value of 0.42 on the strength on final state radiation indicates that the simulation underestimates the strength of final state radiation. There is currently work ongoing aiming to publish the results found in this thesis in the context of an official ATLAS publication. Additionally the uncertainties can be compared with those one would obtain by using only one of the two variables. If one considers only the transverse decay length, a statistical error of Δm{sub Top}{sup stat.}=1.7 GeV and a systematic uncertainty of Δm{sub Top}{sup stat.}=7.8 GeV is obtained, dominated by the uncertainty on initial and final state radiation. The statistical uncertainty obtained by using the transverse momentum of the lepton is with Δm{sub Top}{sup stat.}=1.4 GeV a bit lower than the one obtained by the transverse decay length alone but still larger than the one of the presented measurement. The systematic uncertainty obtained is Δm{sub Top}{sup stat.}=2.7 GeV. Combining the two variables is therefore worthwhile compared with using only the transverse momentum of the lepton alone. The dominant uncertainties on the measurement are caused by imperfect knowledge of the simulation parameters, especially the choice of Monte-Carlo generator. Other large

  20. Measurements of the intrinsic quantum efficiency and absorption length of tetraphenyl butadiene thin films in the vacuum ultraviolet regime

    Science.gov (United States)

    Benson, Christopher; Gann, Gabriel Orebi; Gehman, Victor

    2018-04-01

    A key enabling technology for many liquid noble gas (LNG) detectors is the use of the common wavelength shifting medium tetraphenyl butadiene (TPB). TPB thin films are used to shift ultraviolet scintillation light into the visible spectrum for detection and event reconstruction. Understanding the wavelength shifting efficiency and optical properties of these films are critical aspects in detector performance and modeling and hence in the ultimate physics sensitivity of such experiments. This article presents the first measurements of the room-temperature microphysical quantum efficiency for vacuum-deposited TPB thin films - a result that is independent of the optics of the TPB or substrate. Also presented are measurements of the absorption length in the vacuum ultraviolet regime, the secondary re-emission efficiency, and more precise results for the "black-box" efficiency across a broader spectrum of wavelengths than previous results. The low-wavelength sensitivity, in particular, would allow construction of LNG scintillator detectors with lighter elements (Ne, He) to target light mass WIMPs.

  1. Steps toward improving diet and exercise for cancer survivors (STRIDE): a quasi-randomised controlled trial protocol.

    Science.gov (United States)

    Frensham, Lauren J; Zarnowiecki, Dorota M; Parfitt, Gaynor; Stanley, Rebecca M; Dollman, James

    2014-06-13

    Cancer survivorship rates have increased in developed countries largely due to population ageing and improvements in cancer care. Survivorship is a neglected phase of cancer treatment and is often associated with adverse physical and psychological effects. There is a need for broadly accessible, non-pharmacological measures that may prolong disease-free survival, reduce or alleviate co-morbidities and enhance quality of life. The aim of the Steps TowaRd Improving Diet and Exercise (STRIDE) study is to evaluate the effectiveness of an online-delivered physical activity intervention for increasing walking in cancer survivors living in metropolitan and rural areas of South Australia. This is a quasi-randomised controlled trial. The intervention period is 12-weeks with 3-month follow-up. The trial will be conducted at a university setting and community health services in South Australia. Participants will be insufficiently active and aged 18 years or older. Participants will be randomly assigned to either the intervention or control group. All participants will receive a pedometer but only the intervention group will have access to the STRIDE website where they will report steps, affect and ratings of perceived exertion (RPE) during exercise daily. Researchers will use these variables to individualise weekly step goals to increase walking.The primary outcome measure is steps per day. The secondary outcomes are a) health measures (anthropometric and physiological), b) dietary habits (consumption of core foods and non-core foods) and c) quality of life (QOL) including physical, psychological and social wellbeing. Measures will be collected at baseline, post-intervention and 3-month follow-up. This protocol describes the implementation of a trial using an online resource to assist cancer survivors to become more physically active. It is an innovative tool that uses ratings of perceived exertion and daily affect to create individualised step goals for cancer survivors. The

  2. On the frequency distributions per unit area of the projected and etchable lengths of surface-intersecting fission tracks: influences of track revelation, observation and measurement

    International Nuclear Information System (INIS)

    Jonckheere, R.; Haute, P. van den

    1999-01-01

    In addition to the statistical bounds discussed, thermal history analysis based on the projected and etchable length distributions of surface intersecting fission tracks is limited by systematic factors related to track revelation, observation and measurement. The effects of track revelation, in particular, distort these distributions in the length intervals of interest. An observation threshold poses a problem if it is described by a critical angle θ c , but not if it is described by other criteria proposed in the literature. Measurement imprecisions, predictably, blur the thermal history information contained in these distributions. Measurements of semi-confined tracks, added as a result of surface etching, are a more promising alternative to confined track length measurements for accessing the thermal history record in the fission track length distribution. On the other hand, measurements of the projected lengths of surface intersecting tracks offer the theoretical possibility of determining the true volumetric density N and true mean length m of an arbitrary population of fission tracks, thus allowing direct determination of the corrected age of samples with complex thermal histories. On a methodical level, knowledge of N and m allows to determine the efficiency with which fission tracks are counted under the optical microscope under exactly the same conditions as those under which fission track counts for routine dating purposes are performed

  3. Cervical length measurement for the prediction of preterm birth in multiple pregnancies : a systematic review and bivariate meta-analysis

    NARCIS (Netherlands)

    Lim, A. C.; Hegeman, M. A.; In 't Veld, M. A. Huis; Opmeer, B. C.; Bruinse, H. W.; Mol, B. W. J.

    Objectives To review the literature on cervical length as a predictor of preterm birth in asymptomatic women with a multiple pregnancy. Methods We searched MEDLINE, Embase and reference lists of included articles to identify all studies that reported on the accuracy of cervical length for predicting

  4. Cervical length measurement for the prediction of preterm birth in multiple pregnancies: a systematic review and bivariate meta-analysis

    NARCIS (Netherlands)

    Lim, A. C.; Hegeman, M. A. [=Maud A.; Huis In 't Veld, M. A.; Opmeer, B. C.; Bruinse, H. W.; Mol, B. W. J.

    2011-01-01

    To review the literature on cervical length as a predictor of preterm birth in asymptomatic women with a multiple pregnancy. We searched MEDLINE, Embase and reference lists of included articles to identify all studies that reported on the accuracy of cervical length for predicting preterm birth in

  5. Inter-laboratory validation of the measurement of follicle stimulating hormone (FSH after various lengths of frozen storage

    Directory of Open Access Journals (Sweden)

    Behr Barry

    2010-11-01

    Full Text Available Abstract Background Serum follicle stimulating hormone (FSH levels are used clinically to evaluate infertility, pituitary and gonadal disorders. With increased frequency of research collaborations across institutions, it is essential that inter-laboratory validation is addressed. Methods An inter-laboratory validation of three commercial FSH immunoassays was performed with human serum samples of varying frozen storage length (2 batches of 15 samples each at -25 degree C. Percentage differences and Bland-Altman limits of agreement were calculated. Results The inter- and intra-laboratory consistency of FSH values with the same assay manufacturer was much higher after shorter-term storage (frozen for less than 11 months, mean percentage degradation less than 4% than after long-term storage (2-3 years, mean percentage degradation = 23%. Comparing assay results from different manufacturers, there was similar overall long term degradation as seen with the same manufacturer (-25%, however the degradation was greater when the original FSH was greater than 20 mIU/mL relative to less than 10 mIU/mL (p Conclusion The findings suggest that degradation of serum samples stored between 11 months and 2-3 years at -25 degrees C can lead to unstable FSH measurements. Inter-laboratory variability due to frozen storage time and manufacturer differences in assay results should be accounted for when designing and implementing research or clinical quality control activities involving serum FSH at multiple study sites.

  6. On the neutron charge radius and the new experiments proposed for the precise (n,e) - scattering length measurement

    International Nuclear Information System (INIS)

    Enik, T.L.; Mitsyna, L.V.; Nikolenko, V.G.; Oprea, I.A.; Parzhitsky, S.S.; Popov, A.B.; Samosvat, G.S.; Vtiuryn, V.A.

    1999-01-01

    Relationship between the n,e scattering length, b ne , the neutron mean square charge radius n 2 > and anomalous magnetic moment μ n , the quantities which characterize the internal structure of the neutron, was investigated. The performed analysis showed that in the framework of the modern cloudy bag model (CBM) of the nucleon the values of b ne is determined by the value of n 2 > without the so-called Foldy term being taken into account, while in the framework of the phenomenological Foldy approach the experimental values of ne > obtained up to date can be described only by this Foldy term within an accuracy of about 10%, i.e. by the anomalous magnetic moment of the neutron, μ n . Then a necessity is obvious to obtain b ne with higher accuracy than in previous experiments. To remove the contradictions in the experimental b ne estimates, new experiments to measure the energy dependence of the slow neutron scattering cross section by 86 Kr and scattering anisotropy on Xe isotopes, have been proposed. The investigation has been performed at Frank Laboratory of Neutron Physics, JINR. (authors)

  7. Low-power grating detection system chip for high-speed low-cost length and angle precision measurement

    Science.gov (United States)

    Hou, Ligang; Luo, Rengui; Wu, Wuchen

    2006-11-01

    This paper forwards a low power grating detection chip (EYAS) on length and angle precision measurement. Traditional grating detection method, such as resister chain divide or phase locked divide circuit are difficult to design and tune. The need of an additional CPU for control and display makes these methods' implementation more complex and costly. Traditional methods also suffer low sampling speed for the complex divide circuit scheme and CPU software compensation. EYAS is an application specific integrated circuit (ASIC). It integrates micro controller unit (MCU), power management unit (PMU), LCD controller, Keyboard interface, grating detection unit and other peripherals. Working at 10MHz, EYAS can afford 5MHz internal sampling rate and can handle 1.25MHz orthogonal signal from grating sensor. With a simple control interface by keyboard, sensor parameter, data processing and system working mode can be configured. Two LCD controllers can adapt to dot array LCD or segment bit LCD, which comprised output interface. PMU alters system between working and standby mode by clock gating technique to save power. EYAS in test mode (system action are more frequently than real world use) consumes 0.9mw, while 0.2mw in real world use. EYAS achieved the whole grating detection system function, high-speed orthogonal signal handling in a single chip with very low power consumption.

  8. Measurements of the microwave spectrum, Re-H bond length, and Re quadrupole coupling for HRe(CO)5

    Science.gov (United States)

    Kukolich, Stephen G.; Sickafoose, Shane M.

    1993-11-01

    Rotational transition frequencies for rhenium pentacarbonyl hydride were measured in the 4-10 GHz range using a Flygare-Balle type microwave spectrometer. The rotational constants and Re nuclear quadrupole coupling constants for the four isotopomers, (1) H187Re(CO)5, (2) H185Re(CO)5, (3) D187Re(CO)5, and (4) D185Re(CO)5, were obtained from the spectra. For the most common isotopomer, B(1)=818.5464(2) MHz and eq Q(187Re)=-900.13(3) MHz. The Re-H bond length (r0) determined by fitting the rotational constants is 1.80(1) Å. Although the Re atom is located at a site of near-octahedral symmetry, the quadrupole coupling is large due to the large Re nuclear moments. A 2.7% increase in Re quadrupole coupling was observed for D-substituted isotopomers, giving a rather large isotope effect on the quadrupole coupling. The Cax-Re-Ceq angle is 96(1)°, when all Re-C-O angles are constrained to 180°.

  9. Quantitative fluorescence in situ hybridization measurement of telomere length in skin with/without sun exposure or actinic keratosis.

    Science.gov (United States)

    Ikeda, Hiroyuki; Aida, Junko; Hatamochi, Atsushi; Hamasaki, Yoichiro; Izumiyama-Shimomura, Naotaka; Nakamura, Ken-Ichi; Ishikawa, Naoshi; Poon, Steven S; Fujiwara, Mutsunori; Tomita, Ken-Ichiro; Hiraishi, Naoki; Kuroiwa, Mie; Matsuura, Masaaki; Sanada, Yukihiro; Kawano, Youichi; Arai, Tomio; Takubo, Kaiyo

    2014-03-01

    Chromosomal and genomic instability due to telomere dysfunction is known to play an important role in carcinogenesis. To study telomere shortening in the epidermis surrounding actinic keratosis, we measured telomere lengths of basal, parabasal, and suprabasal cells in epidermis with actinic keratosis (actinic keratosis group, n = 18) and without actinic keratosis (sun-protected, n = 15, and sun-exposed, n = 13 groups) and in actinic keratosis itself as well as in dermal fibroblasts in the 3 groups, using quantitative fluorescence in situ hybridization. Among the 3 cell types, telomeres of basal cells were not always the longest, suggesting that tissue stem cells are not necessarily located among basal cells. Telomeres of basal cells in the sun-exposed group were shorter than those in the sun-protected group. Telomeres in the background of actinic keratosis and in actinic keratosis itself and those of fibroblasts in actinic keratosis were significantly shorter than those in the controls. Our findings demonstrate that sun exposure induces telomere shortening and that actinic keratosis arises from epidermis with shorter telomeres despite the absence of any histologic atypia. © 2014.

  10. Research staff training in a multisite randomized clinical trial: Methods and recommendations from the Stimulant Reduction Intervention using Dosed Exercise (STRIDE) trial.

    Science.gov (United States)

    Walker, Robrina; Morris, David W; Greer, Tracy L; Trivedi, Madhukar H

    2014-01-01

    Descriptions of and recommendations for meeting the challenges of training research staff for multisite studies are limited despite the recognized importance of training on trial outcomes. The STRIDE (STimulant Reduction Intervention using Dosed Exercise) study is a multisite randomized clinical trial that was conducted at nine addiction treatment programs across the United States within the National Drug Abuse Treatment Clinical Trials Network (CTN) and evaluated the addition of exercise to addiction treatment as usual (TAU), compared to health education added to TAU, for individuals with stimulant abuse or dependence. Research staff administered a variety of measures that required a range of interviewing, technical, and clinical skills. In order to address the absence of information on how research staff are trained for multisite clinical studies, the current manuscript describes the conceptual process of training and certifying research assistants for STRIDE. Training was conducted using a three-stage process to allow staff sufficient time for distributive learning, practice, and calibration leading up to implementation of this complex study. Training was successfully implemented with staff across nine sites. Staff demonstrated evidence of study and procedural knowledge via quizzes and skill demonstration on six measures requiring certification. Overall, while the majority of staff had little to no experience in the six measures, all research assistants demonstrated ability to correctly and reliably administer the measures throughout the study. Practical recommendations are provided for training research staff and are particularly applicable to the challenges encountered with large, multisite trials.

  11. Direct observation of the edge spin structure and chain length dependence of a finite haldane chain by high field ESR measurements

    International Nuclear Information System (INIS)

    Yoshida, Makoto; Ohta, Hitoshi; Ito, Toshimitsu; Ajiro, Yoshitami

    2006-01-01

    We have performed high field and multi-frequency ESR measurements of finite length S=1 antiferromagnetic chains in Y 2 BaNi 0.96 Mg 0.04 O 5 . Owing to the high spectral resolution by high fields and high frequencies, observed ESR signals can be separated into the contributions of the finite chains with various chain lengths. Our results clearly show that the edge spins actually interact with each other through the quantum spin chain and the interaction depends on the chain length N. (author)

  12. Comparison of left and right ventricular volume measurement using the Simpson's method and the area length method

    International Nuclear Information System (INIS)

    Hergan, Klaus; Schuster, Antonius; Fruehwald, Julia; Mair, Michael; Burger, Ralph; Toepker, Michael

    2008-01-01

    Purpose: To compare ventricular volume measurement using a volumetric approach in the three standard cardiac planes and ventricular volume estimation by a geometrical model, the Area-Length method (ALM). Materials and methods: Fifty-six healthy volunteers were examined (27 males, 29 females) on a 1.5 T MR-unit with ECG-triggered steady state free precision (SSFP) Cine-MR sequences and parallel image acquisition. Multiple slices in standardized planes including the short-axis view (sa), 4-chamber view (4ch), left and right 2-chamber views (2ch) were used to cover the whole heart. End-systolic and end-diastolic ventricular volumes (EDV, ESV), stroke volume (SV), and ejection fraction (EF) were calculated with Simpson's rule in all planes and with ALM in the 2ch and 4ch planes. Global function parameters measured in the sa plane were compared with those obtained in the other imaging planes. Results: A very good correlation is observed when comparing functional parameters calculated with Simpson's rule in all imaging planes: for instance, the mean EDV/ESV of the left and right ventricle of the female population group measured in sa, 4ch, and 2ch: left ventricle EDV/ESV 114.3/44.4, 120.9/46.5, and 117.7/45.3 ml; right ventricle EDV/ESV 106.6/46.0, 101.2/41.1, and 103.5/43.0 ml. Functional parameters of the left ventricle calculated with ALM in 2ch and 4ch correlate to parameters obtained in sa with Simpson's rule in the range of 5-10%: for instance, the EDV/ESV of the left ventricle of the male population group measured in the sa, 4ch, and 2ch: 160.3/63.5, 163.1/59.0, and 167.0/65.7 ml. Functional parameters of the right ventricle measured with ALM in 4ch are 40-50% lower and calculated in 2ch almost double as high as compared with the parameters obtained in sa with Simpson's rule: for instance, male right ventricular EDV/ESV measured in sa, 4ch, and 2ch: 153.4/68.1, 97.5/34.5, and 280.2/123.2 ml. The EF correlates for all imaging planes measured with the Simpson's rule

  13. Fundamental length and relativistic length

    International Nuclear Information System (INIS)

    Strel'tsov, V.N.

    1988-01-01

    It si noted that the introduction of fundamental length contradicts the conventional representations concerning the contraction of the longitudinal size of fast-moving objects. The use of the concept of relativistic length and the following ''elongation formula'' permits one to solve this problem

  14. Together We STRIDE: A quasi-experimental trial testing the effectiveness of a multi-level obesity intervention for Hispanic children in rural communities.

    Science.gov (United States)

    Ko, Linda K; Rillamas-Sun, Eileen; Bishop, Sonia; Cisneros, Oralia; Holte, Sarah; Thompson, Beti

    2018-04-01

    Hispanic children are disproportionally overweight and obese compared to their non-Hispanic white counterparts in the US. Community-wide, multi-level interventions have been successful to promote healthier nutrition, increased physical activity (PA), and weight loss. Using community-based participatory approach (CBPR) that engages community members in rural Hispanic communities is a promising way to promote behavior change, and ultimately weight loss among Hispanic children. Led by a community-academic partnership, the Together We STRIDE (Strategizing Together Relevant Interventions for Diet and Exercise) aims to test the effectiveness of a community-wide, multi-level intervention to promote healthier diets, increased PA, and weight loss among Hispanic children. The Together We STRIDE is a parallel quasi-experimental trial with a goal of recruiting 900 children aged 8-12 years nested within two communities (one intervention and one comparison). Children will be recruited from their respective elementary schools. Components of the 2-year multi-level intervention include comic books (individual-level), multi-generational nutrition and PA classes (family-level), teacher-led PA breaks and media literacy education (school-level), family nights, a farmer's market and a community PA event (known as ciclovia) at the community-level. Children from the comparison community will receive two newsletters. Height and weight measures will be collected from children in both communities at three time points (baseline, 6-months, and 18-months). The Together We STRIDE study aims to promote healthier diet and increased PA to produce healthy weight among Hispanic children. The use of CBPR approach and the engagement of the community will springboard strategies for intervention' sustainability. Clinical Trials Registration Number: NCT02982759 Retrospectively registered. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Flame Length

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — Flame length was modeled using FlamMap, an interagency fire behavior mapping and analysis program that computes potential fire behavior characteristics. The tool...

  16. Determination of the length and position of the lower oesophageal sphincter (LOS) by correlation of external measurements with combined radiographic and manometric estimations in the cat

    International Nuclear Information System (INIS)

    Hashim, M.A.; Waterman, A.E.

    1992-01-01

    Fifty DSH cats were studied radiographically and a highly significant linear correlation was found between the length of the oesophagus measured to the diaphragmatic line on the radiographs and the externally measured distance from the lower jaw incisor teeth to the anterior border of the head of 10th rib. A subsequent manometric study utilizing this correlation in 40 cats suggests that the functional lower oesophageal sphincter (LOS) is situated almost at the level of the diaphragm in the cat. Significant differences were found between the length of the LOS in cats anaesthetized with ketamine compared to alphaxalone-alphadolone or xylazine-ketamine-atropine. The mean lengths of the LOS was 1.42 +/- 0.3 cm. The findings of this study indicate that external measurements can be used to position catheters for accurate oesophageal manometry in the cat

  17. Length and elasticity of side reins affect rein tension at trot.

    Science.gov (United States)

    Clayton, Hilary M; Larson, Britt; Kaiser, LeeAnn J; Lavagnino, Michael

    2011-06-01

    This study investigated the horse's contribution to tension in the reins. The experimental hypotheses were that tension in side reins (1) increases biphasically in each trot stride, (2) changes inversely with rein length, and (3) changes with elasticity of the reins. Eight riding horses trotted in hand at consistent speed in a straight line wearing a bit and bridle and three types of side reins (inelastic, stiff elastic, compliant elastic) were evaluated in random order at long, neutral, and short lengths. Strain gauge transducers (240 Hz) measured minimal, maximal and mean rein tension, rate of loading and impulse. The effects of rein type and length were evaluated using ANOVA with Bonferroni post hoc tests. Rein tension oscillated in a regular pattern with a peak during each diagonal stance phase. Within each rein type, minimal, maximal and mean tensions were higher with shorter reins. At neutral or short lengths, minimal tension increased and maximal tension decreased with elasticity of the reins. Short, inelastic reins had the highest maximal tension and rate of loading. Since the tension variables respond differently to rein elasticity at different lengths, it is recommended that a set of variables representing different aspects of rein tension should be reported. Copyright © 2010 Elsevier Ltd. All rights reserved.

  18. Children with lower limb length inequality: The measurement of inequality, the timing of physiodesis and gait analysis

    NARCIS (Netherlands)

    H.I.H. Lampe

    1997-01-01

    textabstractThe symmetry of the human locomotion apparatus makes inequality of the limbs an aberrant finding for both patient and doctor. 4-15% of the healthy, adult population, has a limb length inequality (LLI) of one cm or more. A minor discrepancy of less than one cm is therefore common and many

  19. Measurements on the influence of the length of the daily submergence time on the condition and appearence of mussels (

    NARCIS (Netherlands)

    Basal, M.

    1972-01-01

    Mussels (Mytilus edulis) living at different intertidal levels (viz. about 40, 10 and 0% of time exposed to the air) were compared as to length distribution, meat and shell weight, and linear dimensions. The long-exposed mussels were found to be on average smaller, to contain less meat, to

  20. Measurement of the diffusion length of thermal neutrons inside graphite; Mesure de la longueur de diffusion des neutrons thermiques dans le graphite

    Energy Technology Data Exchange (ETDEWEB)

    Ertaud, A; Beauge, R; Fauquez, H; De Laboulay, H; Mercier, C; Vautrey, L

    1948-11-01

    The diffusion length of thermal neutrons inside a given industrial graphite is determined by measuring the neutron density inside a parallelepipedal piling up of graphite bricks (2.10 x 2.10 x 2.442 m). A 3.8 curies (Ra {alpha} {yields} Be) source is placed inside the parallelepipedal block of graphite and thin manganese detectors are used. Corrections are added to the unweighted measurements to take into account the effects of the damping of supra-thermal neutrons in the measurement area. These corrections are experimentally deduced from the differential measurements made with a cadmium screen interposed between the source and the first plane of measurement. An error analysis completes the report. The diffusion length obtained is: L = 45.7 cm {+-} 0.3. The average density of the graphite used is 1.76 and the average apparent density of the piling up is 1.71. (J.S.)

  1. Fundamental length

    International Nuclear Information System (INIS)

    Pradhan, T.

    1975-01-01

    The concept of fundamental length was first put forward by Heisenberg from purely dimensional reasons. From a study of the observed masses of the elementary particles known at that time, it is sumrised that this length should be of the order of magnitude 1 approximately 10 -13 cm. It was Heisenberg's belief that introduction of such a fundamental length would eliminate the divergence difficulties from relativistic quantum field theory by cutting off the high energy regions of the 'proper fields'. Since the divergence difficulties arise primarily due to infinite number of degrees of freedom, one simple remedy would be the introduction of a principle that limits these degrees of freedom by removing the effectiveness of the waves with a frequency exceeding a certain limit without destroying the relativistic invariance of the theory. The principle can be stated as follows: It is in principle impossible to invent an experiment of any kind that will permit a distintion between the positions of two particles at rest, the distance between which is below a certain limit. A more elegant way of introducing fundamental length into quantum theory is through commutation relations between two position operators. In quantum field theory such as quantum electrodynamics, it can be introduced through the commutation relation between two interpolating photon fields (vector potentials). (K.B.)

  2. Effect of treadmill versus overground running on the structure of variability of stride timing.

    Science.gov (United States)

    Lindsay, Timothy R; Noakes, Timothy D; McGregor, Stephen J

    2014-04-01

    Gait timing dynamics of treadmill and overground running were compared. Nine trained runners ran treadmill and track trials at 80, 100, and 120% of preferred pace for 8 min. each. Stride time series were generated for each trial. To each series, detrended fluctuation analysis (DFA), power spectral density (PSD), and multiscale entropy (MSE) analysis were applied to infer the regime of control along the randomness-regularity axis. Compared to overground running, treadmill running exhibited a higher DFA and PSD scaling exponent, as well as lower entropy at non-preferred speeds. This indicates a more ordered control for treadmill running, especially at non-preferred speeds. The results suggest that the treadmill itself brings about greater constraints and requires increased voluntary control. Thus, the quantification of treadmill running gait dynamics does not necessarily reflect movement in overground settings.

  3. Design, fabrication, and calibration of curved integral coils for measuring transfer function, uniformity, and effective length of LBL ALS [Lawrence Berkeley Laboratory Advanced Light Source] Booster Dipole Magnets

    International Nuclear Information System (INIS)

    Green, M.I.; Nelson, D.; Marks, S.; Gee, B.; Wong, W.; Meneghetti, J.

    1989-03-01

    A matched pair of curved integral coils has been designed, fabricated and calibrated at Lawrence Berkeley Laboratory for measuring Advanced Light Source (ALS) Booster Dipole Magnets. Distinctive fabrication and calibration techniques are described. The use of multifilar magnet wire in fabrication integral search coils is described. Procedures used and results of AC and DC measurements of transfer function, effective length and uniformity of the prototype booster dipole magnet are presented in companion papers. 8 refs

  4. Estimation of radiative forcing and chore length of shallow convective clouds (SCC) based on broadband pyranometer measurement network

    Science.gov (United States)

    Shi, H.

    2017-12-01

    We presented a method to identify and calculate cloud radiative forcing (CRF) and horizontal chore length (L) of shallow convective clouds (SCC) using a network of 9 broadband pyranometers. The analyzing data was collected from the SCC campaign during two years summers (2015 2016) at Baiqi site over Inner Mongolia grassland. The network of pyranometers was operated across a spatial domain covering 42.16-42.30° N and 114.83-114.98° E. The SCC detection method was verified by observer reports and cameras, which showed that the detection method and human observations were in agreement about 75 %. The differences between the SCC detection method and human observations can be responsible for following factors: 1) small or dissipating clouds can be neglected for the value of 1 min of temporal resolution of pyranometer; 2) human observation recorded weather conditions four times every day; 3) SCC was indistinguishable from coexistence of SCC and Cirrus (Ci); 4) the SCC detection method is weighted toward clouds crossing the sun's path, while the human observer can view clouds over the entire sky. The deviation of L can be attributed to two factors: 1) the accuracy of wind speed at height of SCC and the ratio of horizontal and vertical length play a key role in determine values of L; 2) the effect of variance of solar zenith angle can be negligible. The downwelling shortwave CRF of SCC was -134.1 Wm-2. The average value of L of SCC was 1129 m. Besides, the distribution of normalized cloud chore length agreed well with power-law fit.

  5. First observation of $\\pi^{-}K^+$ and $\\pi^{+}K^-$ atoms, their lifetime measurement and $\\pi K$ scattering lengths evaluation

    CERN Document Server

    Afanasyev, Leonid

    2016-01-01

    The Low Energy QCD allows to calculate the ππ and π K scattering lengths with high precision. There are accurate relations between these scattering lengths and π + π − , π − K + , π + K − atoms lifetimes. The experiment on the first observation of π − K + and π + K − atoms is described. The atoms were generated in Nickel and Platinum targets hit by the PS CERN proton beam with momentum of 24 GeV/ c . Moving in the target, part of atoms break up producing characteristic π K pairs (atomic pairs) with small relative momentum Q in their c.m.s. In the experiment, we detected n A = 349 ± 62 (5.6 standard deviations) π − K + and π + K − atomic pairs. The main part of π K pairs are produced in free state. The majority of such particles are generated directly or from short-lived sources as ρ , ω and similar resonances. The electromagnetic interactions in the final state create Coulomb pairs with a known sharp dependence on Q . This effect allows to evaluate the number of these Coulomb pai...

  6. Effects of a wearable exoskeleton stride management assist system (SMA®) on spatiotemporal gait characteristics in individuals after stroke: a randomized controlled trial.

    Science.gov (United States)

    Buesing, Carolyn; Fisch, Gabriela; O'Donnell, Megan; Shahidi, Ida; Thomas, Lauren; Mummidisetty, Chaithanya K; Williams, Kenton J; Takahashi, Hideaki; Rymer, William Zev; Jayaraman, Arun

    2015-08-20

    Robots offer an alternative, potentially advantageous method of providing repetitive, high-dosage, and high-intensity training to address the gait impairments caused by stroke. In this study, we compared the effects of the Stride Management Assist (SMA®) System, a new wearable robotic device developed by Honda R&D Corporation, Japan, with functional task specific training (FTST) on spatiotemporal gait parameters in stroke survivors. A single blinded randomized control trial was performed to assess the effect of FTST and task-specific walking training with the SMA® device on spatiotemporal gait parameters. Participants (n=50) were randomly assigned to FTST or SMA. Subjects in both groups received training 3 times per week for 6-8 weeks for a maximum of 18 training sessions. The GAITRite® system was used to collect data on subjects' spatiotemporal gait characteristics before training (baseline), at mid-training, post-training, and at a 3-month follow-up. After training, significant improvements in gait parameters were observed in both training groups compared to baseline, including an increase in velocity and cadence, a decrease in swing time on the impaired side, a decrease in double support time, an increase in stride length on impaired and non-impaired sides, and an increase in step length on impaired and non-impaired sides. No significant differences were observed between training groups; except for SMA group, step length on the impaired side increased significantly during self-selected walking speed trials and spatial asymmetry decreased significantly during fast-velocity walking trials. SMA and FTST interventions provided similar, significant improvements in spatiotemporal gait parameters; however, the SMA group showed additional improvements across more parameters at various time points. These results indicate that the SMA® device could be a useful therapeutic tool to improve spatiotemporal parameters and contribute to improved functional mobility in

  7. Repeated sprint ability and stride kinematics are altered following an official match in national-level basketball players.

    Science.gov (United States)

    Delextrat, A; Baliqi, F; Clarke, N

    2013-04-01

    The aim of the study was to investigate the effects of playing an official national-level basketball match on repeated sprint ability (RSA) and stride kinematics. Nine male starting basketball players (22.8±2.2 years old, 191.3±5.8 cm, 88±10.3 kg, 12.3±4.6% body fat) volunteered to take part. Six repetitions of maximal 4-s sprints were performed on a non-motorised treadmill, separated by 21-s of passive recovery, before and immediately after playing an official match. Fluid loss, playing time, and the frequencies of the main match activities were recorded. The peak, mean, and performance decrement for average and maximal speed, acceleration, power, vertical and horizontal forces, and stride parameters were calculated over the six sprints. Differences between pre- and post-match were assessed by student t-tests. Significant differences between pre- and post-tests were observed in mean speed (-3.3%), peak and mean horizontal forces (-4.3% and -17.4%), peak and mean vertical forces (-3.4% and -3.7%), contact time (+7.3%), stride duration (+4.6%) and stride frequency (-4.0%), (Pvertical force were significantly correlated to fluid loss and sprint, jump and shuffle frequencies (P<0.05). These results highlight that the impairment in repeated sprint ability depends on the specific activities performed, and that replacing fluid loss through sweating during a match is crucial.

  8. Automated health alerts from Kinect-based in-home gait measurements.

    Science.gov (United States)

    Stone, Erik E; Skubic, Marjorie; Back, Jessica

    2014-01-01

    A method for automatically generating alerts to clinicians in response to changes in in-home gait parameters is investigated. Kinect-based gait measurement systems were installed in apartments in a senior living facility. The systems continuously monitored the walking speed, stride time, and stride length of apartment residents. A framework for modeling uncertainty in the residents' gait parameter estimates, which is critical for robust change detection, is developed; along with an algorithm for detecting changes that may be clinically relevant. Three retrospective case studies, of individuals who had their gait monitored for periods ranging from 12 to 29 months, are presented to illustrate use of the alert method. Evidence suggests that clinicians could be alerted to health changes at an early stage, while they are still small and interventions may be most successful. Additional potential uses are also discussed.

  9. Effects of correlations between particle longitudinal positions and transverse plane on bunch length measurement: a case study on GBS electron LINAC at ELI-NP

    Science.gov (United States)

    Sabato, L.; Arpaia, P.; Cianchi, A.; Liccardo, A.; Mostacci, A.; Palumbo, L.; Variola, A.

    2018-02-01

    In high-brightness LINear ACcelerators (LINACs), electron bunch length can be measured indirectly by a radio frequency deflector (RFD). In this paper, the accuracy loss arising from non-negligible correlations between particle longitudinal positions and the transverse plane (in particular the vertical one) at RFD entrance is analytically assessed. Theoretical predictions are compared with simulation results, obtained by means of ELEctron Generation ANd Tracking (ELEGANT) code, in the case study of the gamma beam system (GBS) at the extreme light infrastructure—nuclear physics (ELI-NP). In particular, the relative error affecting the bunch length measurement, for bunches characterized by both energy chirp and fixed correlation coefficients between longitudinal particle positions and the vertical plane, is reported. Moreover, the relative error versus the correlation coefficients is shown for fixed RFD phase 0 rad and π rad. The relationship between relative error and correlations factors can help the decision of using the bunch length measurement technique with one or two vertical spot size measurements in order to cancel the correlations contribution. In the case of the GBS electron LINAC, the misalignment of one of the quadrupoles before the RFD between  -2 mm and 2 mm leads to a relative error less than 5%. The misalignment of the first C-band accelerating section between  -2 mm and 2 mm could lead to a relative error up to 10%.

  10. Educational attainment but not measures of current socioeconomic circumstances are associated with leukocyte telomere length in healthy older men and women.

    Science.gov (United States)

    Steptoe, Andrew; Hamer, Mark; Butcher, Lee; Lin, Jue; Brydon, Lena; Kivimäki, Mika; Marmot, Michael; Blackburn, Elizabeth; Erusalimsky, Jorge D

    2011-10-01

    Low socioeconomic status (SES) may be associated with accelerated biological aging, but findings relating SES with telomere length have been inconsistent. We tested the hypotheses that shorter telomere length and telomerase activity would be related more robustly to education, an early life indicator of socioeconomic position, than to current indicators of socioeconomic circumstances. Healthy men and women aged 53-76 years from the Whitehall II epidemiological cohort provided blood samples from which telomere length was assessed in 448 and telomerase activity in 416. Educational attainment was classified into four levels, while household income and grade of employment were measured as indicators of current socioeconomic circumstances. Age, gender, blood pressure, glycated hemoglobin, high density lipoprotein cholesterol, smoking, body mass index and physical activity were included as covariates. We found that lower educational attainment was associated with shorter telomere length after controlling statistically for biological and behavioral covariates. Neither household income nor employment grade was related to telomere length. The association between telomere length and education remained significant after adjusting for current socioeconomic circumstances. In men, highest levels of telomerase activity were found in the lowest education group. We conclude that low SES defined in terms of education but not current socioeconomic circumstances is associated with shortened telomeres. Low educational attainment may be an indicator of long-term SES trajectories, and be associated with accumulated allostatic load resulting in telomere shortening. Education may also promote problem-solving skills leading to reduced biological stress responsivity, with favorable consequences for biological aging. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. Impact of stride-coupled gaze shifts of walking blowflies on the neuronal representation of visual targets

    Directory of Open Access Journals (Sweden)

    Daniel eKress

    2014-09-01

    Full Text Available During locomotion animals rely heavily on visual cues gained from the environment to guide their behavior. Examples are basic behaviors like collision avoidance or the approach to a goal. The saccadic gaze strategy of flying flies, which separates translational from rotational phases of locomotion, has been suggested to facilitate the extraction of environmental information, because only image flow evoked by translational self-motion contains relevant distance information about the surrounding world. In contrast to the translational phases of flight during which gaze direction is kept largely constant, walking flies experience continuous rotational image flow that is coupled to their stride-cycle. The consequences of these self-produced image shifts for the extraction of environmental information are still unclear. To assess the impact of stride-coupled image shifts on visual information processing, we performed electrophysiological recordings from the HSE cell, a motion sensitive wide-field neuron in the blowfly visual system. This cell has been concluded to play a key role in mediating optomotor behavior, self-motion estimation and spatial information processing. We used visual stimuli that were based on the visual input experienced by walking blowflies while approaching a black vertical bar. The response of HSE to these stimuli was dominated by periodic membrane potential fluctuations evoked by stride-coupled image shifts. Nevertheless, during the approach the cell’s response contained information about the bar and its background. The response components evoked by the bar were larger than the responses to its background, especially during the last phase of the approach. However, as revealed by targeted modifications of the visual input during walking, the extraction of distance information on the basis of HSE responses is much impaired by stride-coupled retinal image shifts. Possible mechanisms that may cope with these stride

  12. Stimulant Reduction Intervention using Dosed Exercise (STRIDE - CTN 0037: Study protocol for a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Morris David W

    2011-09-01

    Full Text Available Abstract Background There is a need for novel approaches to the treatment of stimulant abuse and dependence. Clinical data examining the use of exercise as a treatment for the abuse of nicotine, alcohol, and other substances suggest that exercise may be a beneficial treatment for stimulant abuse, with direct effects on decreased use and craving. In addition, exercise has the potential to improve other health domains that may be adversely affected by stimulant use or its treatment, such as sleep disturbance, cognitive function, mood, weight gain, quality of life, and anhedonia, since it has been shown to improve many of these domains in a number of other clinical disorders. Furthermore, neurobiological evidence provides plausible mechanisms by which exercise could positively affect treatment outcomes. The current manuscript presents the rationale, design considerations, and study design of the National Institute on Drug Abuse (NIDA Clinical Trials Network (CTN CTN-0037 Stimulant Reduction Intervention using Dosed Exercise (STRIDE study. Methods/Design STRIDE is a multisite randomized clinical trial that compares exercise to health education as potential treatments for stimulant abuse or dependence. This study will evaluate individuals diagnosed with stimulant abuse or dependence who are receiving treatment in a residential setting. Three hundred and thirty eligible and interested participants who provide informed consent will be randomized to one of two treatment arms: Vigorous Intensity High Dose Exercise Augmentation (DEI or Health Education Intervention Augmentation (HEI. Both groups will receive TAU (i.e., usual care. The treatment arms are structured such that the quantity of visits is similar to allow for equivalent contact between groups. In both arms, participants will begin with supervised sessions 3 times per week during the 12-week acute phase of the study. Supervised sessions will be conducted as one-on-one (i.e., individual sessions

  13. Device method for accurate measuring length of edible casing%食用肠衣的精确测量装置及方法

    Institute of Scientific and Technical Information of China (English)

    朱秋晨; 孙维连; 孙铂

    2012-01-01

    Edible casing is in light weight, which has higher economic value, resilience, greasy and smooth properties, but it is more difficult to measure the length of that. Through studying the demands of the market, a new machine for measuring the length of edible casing was designed. Its band carrier drew the casing moving and stepping motor controled the speed of band carrier. The data of the measuring wheel were recorded by high-accuracy circle encoder, the speed of stepping motor was regulated by Programmable Logic Controller, and control parameters were inputted and measurement data were showed by touch screen, etc. As the use of key technology, the problems of measurement of edible casing length were solved. The speed reached 0.84 m/s, and the efficiency of the machine was twice of the manual measurement. High automation system makes the work of measuring the length of edible casing reliable and the environment of production healthy. Practice proves that the measurement system of casing can meet the requirements of production process, the measurement error is equal or lesser than 0.4%, the measurement precision was improved.%食用肠衣质量轻,经济价值高,具有弹性、油腻和光滑等特性,精确测量其长度比较困难.通过研究市场的需求,设计了一种肠衣传送测量机构,由传送带牵引肠衣移动,步进电动机控制传送带的速度.采用高精度圆形编码器记录测长轮数据,可编程序控制器调控步进电动机的运行速度,触摸屏输入控制参数和显示测量数据等技术,解决了肠衣精确测量问题.系统的测量速度可达0.84 m/s,测量效率是人工测量的2倍,系统自动化程度高,工作可靠,生产环境卫生.实践证明,肠衣测量系统可满足生产工艺的要求,肠衣测量误差≤0.4%,提高了测量精度.

  14. Telomere length and depression

    DEFF Research Database (Denmark)

    Wium-Andersen, Marie Kim; Ørsted, David Dynnes; Rode, Line

    2017-01-01

    BACKGROUND: Depression has been cross-sectionally associated with short telomeres as a measure of biological age. However, the direction and nature of the association is currently unclear. AIMS: We examined whether short telomere length is associated with depression cross-sectionally as well...... as prospectively and genetically. METHOD: Telomere length and three polymorphisms, TERT, TERC and OBFC1, were measured in 67 306 individuals aged 20-100 years from the Danish general population and associated with register-based attendance at hospital for depression and purchase of antidepressant medication....... RESULTS: Attendance at hospital for depression was associated with short telomere length cross-sectionally, but not prospectively. Further, purchase of antidepressant medication was not associated with short telomere length cross-sectionally or prospectively. Mean follow-up was 7.6 years (range 0...

  15. Prediction of preterm birth in multiple pregnancies: development of a multivariable model including cervical length measurement at 16 to 21 weeks' gestation.

    Science.gov (United States)

    van de Mheen, Lidewij; Schuit, Ewoud; Lim, Arianne C; Porath, Martina M; Papatsonis, Dimitri; Erwich, Jan J; van Eyck, Jim; van Oirschot, Charlotte M; Hummel, Piet; Duvekot, Johannes J; Hasaart, Tom H M; Groenwold, Rolf H H; Moons, Karl G M; de Groot, Christianne J M; Bruinse, Hein W; van Pampus, Maria G; Mol, Ben W J

    2014-04-01

    To develop a multivariable prognostic model for the risk of preterm delivery in women with multiple pregnancy that includes cervical length measurement at 16 to 21 weeks' gestation and other variables. We used data from a previous randomized trial. We assessed the association between maternal and pregnancy characteristics including cervical length measurement at 16 to 21 weeks' gestation and time to delivery using multivariable Cox regression modelling. Performance of the final model was assessed for the outcomes of preterm and very preterm delivery using calibration and discrimination measures. We studied 507 women, of whom 270 (53%) delivered models for preterm and very preterm delivery had a c-index of 0.68 (95% CI 0.63 to 0.72) and 0.68 (95% CI 0.62 to 0.75), respectively, and showed good calibration. In women with a multiple pregnancy, the risk of preterm delivery can be assessed with a multivariable model incorporating cervical length and other predictors.

  16. PIV measurements of the turbulence integral length scale on cold combustion flow field of tangential firing boiler

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Wen-fei; Xie, Jing-xing; Gong, Zhi-jun; Li, Bao-wei [Inner Mongolia Univ. of Science and Technology, Baotou (China). Inner Mongolia Key Lab. for Utilization of Bayan Obo Multi-Metallic Resources: Elected State Key Lab.

    2013-07-01

    The process of the pulverized coal combustion in tangential firing boiler has prominent significance on improving boiler operation efficiency and reducing NO{sub X} emission. This paper aims at researching complex turbulent vortex coherent structure formed by the four corners jets in the burner zone, a cold experimental model of tangential firing boiler has been built. And by employing spatial correlation analysis method and PIV (Particle Image Velocimetry) technique, the law of Vortex scale distribution on the three typical horizontal layers of the model based on the turbulent Integral Length Scale (ILS) has been researched. According to the correlation analysis of ILS and the temporal average velocity, it can be seen that the turbulent vortex scale distribution in the burner zone of the model is affected by both jet velocity and the position of wind layers, and is not linear with the variation of jet velocity. The vortex scale distribution of the upper primary air is significantly different from the others. Therefore, studying the ILS of turbulent vortex integral scale is instructive to high efficiency cleaning combustion of pulverized coal in theory.

  17. Comparison of four measures in reducing length of stay in burns: An Asian centre's evolved multimodal burns protocol.

    Science.gov (United States)

    Chong, Si Jack; Kok, Yee Onn; Choke, Abby; Tan, Esther W X; Tan, Kok Chai; Tan, Bien-Keem

    2017-09-01

    Multidisciplinary burns care is constantly evolving to improve outcomes given the numerous modalities available. We examine the use of Biobrane, micrografting, early renal replacement therapy and a strict target time of surgery within 24h of burns on improving outcomes of length of stay, duration of surgery, mean number of surgeries and number of positive tissue cultures in a tertiary burns centre. A post-implementation prospective cohort of inpatient burns patients from 2014 to 2015 (n=137) was compared against a similar pre-implementation cohort from 2013 to 2014 (n=93) using REDCAP, an electronic database. There was no statistically significant difference for comorbidities, age and percentage (%) TBSA between the new protocol and control groups. The protocol group had shorter mean time to surgery (23.5-38.5h) (pburns protocol improved burns care and validated the collective effort of a multi-disciplinary, multipronged burns management supported by surgeons, anesthetists, renal physicians, emergency physicians, nurses, and allied healthcare providers. Biobrane, single stage onlay micrograft/allograft, early CRRT and surgery within 24h were successfully introduced. These are useful adjuncts in the armamentarium to be considered for any burns centre. Copyright © 2017. Published by Elsevier Ltd.

  18. Can Tai Chi training impact fractal stride time dynamics, an index of gait health, in older adults? Cross-sectional and randomized trial studies.

    Directory of Open Access Journals (Sweden)

    Brian J Gow

    Full Text Available To determine if Tai Chi (TC has an impact on long-range correlations and fractal-like scaling in gait stride time dynamics, previously shown to be associated with aging, neurodegenerative disease, and fall risk.Using Detrended Fluctuation Analysis (DFA, this study evaluated the impact of TC mind-body exercise training on stride time dynamics assessed during 10 minute bouts of overground walking. A hybrid study design investigated long-term effects of TC via a cross-sectional comparison of 27 TC experts (24.5 ± 11.8 yrs experience and 60 age- and gender matched TC-naïve older adults (50-70 yrs. Shorter-term effects of TC were assessed by randomly allocating TC-naïve participants to either 6 months of TC training or to a waitlist control. The alpha (α long-range scaling coefficient derived from DFA and gait speed were evaluated as outcomes.Cross-sectional comparisons using confounder adjusted linear models suggest that TC experts exhibited significantly greater long-range scaling of gait stride time dynamics compared with TC-naïve adults. Longitudinal random-slopes with shared baseline models accounting for multiple confounders suggest that the effects of shorter-term TC training on gait dynamics were not statistically significant, but trended in the same direction as longer-term effects although effect sizes were very small. In contrast, gait speed was unaffected in both cross-sectional and longitudinal comparisons.These preliminary findings suggest that fractal-like measures of gait health may be sufficiently precise to capture the positive effects of exercise in the form of Tai Chi, thus warranting further investigation. These results motivate larger and longer-duration trials, in both healthy and health-challenged populations, to further evaluate the potential of Tai Chi to restore age-related declines in gait dynamics.The randomized trial component of this study was registered at ClinicalTrials.gov (NCT01340365.

  19. Accuracy of two root canal length measurement devices integrated into rotary endodontic motors when removing gutta-percha from root-filled teeth.

    Science.gov (United States)

    Uzun, O; Topuz, O; Tinaz, C; Nekoofar, M H; Dummer, P M H

    2008-09-01

    To evaluate ex vivo the accuracy of the integrated electronic root canal length measurement devices within TCM Endo V and Tri Auto ZX motors whilst removing gutta-percha and sealer from filled root canals. Forty freshly extracted maxillary and mandibular incisor teeth with mature apices were selected. Following access cavity preparation, the length of the root canals were measured visually 0.5 mm short of the major foramen (TL). The canals were prepared using the HERO 642 system and then filled with gutta-percha and AH26 sealer using a lateral compaction technique. After 7 days the coronal temporary filling was removed and the roots mounted in an alginate experimental model. The roots were then randomly divided in two groups. The access cavities were filled with chloroform to soften the gutta-percha and allow its penetration using the Tri Auto ZX and the TCM Endo V devices in groups 1 and 2, respectively. The 'automatic apical reverse function' (ARL) of both devices was set to start at the 0.5 setting and the rotary instrument inserted inside the root canal until a beeping sound was heard and the rotation of the file stopped automatically. Once the auto reverse function had been initiated, the foot pedal of the motor was inactivated and the rubber stop placed against the reference point. The distance between the file tip and rubber stop was measured using a digital calliper to 0.01 mm accuracy (ARL). Then, a size 20, 0.02 taper instrument was attached to each device and inserted into the root canals without rotary motion until the integrated ERCLMDs positioned the instrument tips at the 0.5 setting as suggested by the devices. This length was again measured using a digital calliper (EL). The Mann-Whitney U-test was used to investigate statistical differences between the true canal length and those indicated by the two devices when used in 'automatic ARL and when inserted passively (EL). In the presence of gutta-percha, sealer and chloroform, the auto

  20. Design and validation of a 3D virtual reality desktop system for sonographic length and volume measurements in early pregnancy evaluation.

    Science.gov (United States)

    Baken, Leonie; van Gruting, Isabelle M A; Steegers, Eric A P; van der Spek, Peter J; Exalto, Niek; Koning, Anton H J

    2015-03-01

    To design and validate a desktop virtual reality (VR) system, for presentation and assessment of volumetric data, based on commercially off-the-shelf hardware as an alternative to a fully immersive CAVE-like I-Space VR system. We designed a desktop VR system, using a three-dimensional (3D) monitor and a six degrees-of-freedom tracking system. A personal computer uses the V-Scope (Erasmus MC, Rotterdam, The Netherlands) volume-rendering application, developed for the I-Space, to create a hologram of volumetric data. Inter- and intraobserver reliability for crown-rump length and embryonic volume measurements are investigated using Bland-Altman plots and intraclass correlation coefficients. Time required for the measurements was recorded. Comparing the I-Space and the desktop VR system, the mean difference for crown-rump length is -0.34% (limits of agreement -2.58-1.89, ±2.24%) and for embryonic volume -0.92% (limits of agreement -6.97-5.13, ±6.05%). Intra- and interobserver intraclass correlation coefficients of the desktop VR system were all >0.99. Measurement times were longer on the desktop VR system compared with the I-Space, but the differences were not statistically significant. A user-friendly desktop VR system can be put together using commercially off-the-shelf hardware at an acceptable price. This system provides a valid and reliable method for embryonic length and volume measurements and can be used in clinical practice. © 2014 Wiley Periodicals, Inc.

  1. Sub-recoil cooling up to nano-Kelvin. Direct measurement of spatial coherency length. New tests for Levy statistics

    International Nuclear Information System (INIS)

    Saubamea, B.

    1998-12-01

    This thesis presents a new method to measure the temperature of ultracold atoms from the spatial autocorrelation function of the atomic wave-packets. We thus determine the temperature of metastable helium-4 atoms cooled by velocity selective dark resonance, a method known to cool the atoms below the temperature related to the emission or the absorption of a single photon by an atom at rest, namely the recoil temperature. This cooling mechanism prepares each atom in a coherent superposition of two wave-packets with opposite mean momenta, which are initially superimposed and then drift apart. By measuring the temporal decay of their overlap, we have access to the Fourier transform of the momentum distribution of the atoms. Using this method, we can measure temperatures as low as 5 nK, 800 times as small as the recoil temperature. Moreover we study in detail the exact shape of the momentum distribution and compare the experimental results with two different theoretical approaches: a quantum Monte Carlo simulation and an analytical model based on Levy statistics. We compare the calculated line shape with the one deduced from simulations, and each theoretical model with experimental data. A very good agreement is found with each approach. We thus demonstrate the validity of the statistical model of sub-recoil cooling and give the first experimental evidence of some of its characteristics: the absence of steady-state, the self-similarity and the non Lorentzian shape of the momentum distribution of the cooled atoms. All these aspects are related to the non ergodicity of sub-recoil cooling. (author)

  2. Comparison of anterior segment measurements using Sirius Topographer® and Nidek Axial Length-Scan® with assessing repeatability in patients with cataracts

    Directory of Open Access Journals (Sweden)

    Resat Duman

    2018-01-01

    Full Text Available Purpose: The purpose of this study is to evaluate anterior segment measurements obtained using CSO Sirius Topographer® (CSO, Firenze, Italy and Nidek Axial Length (AL-Scan® (Nidek CO., Gamagori, Japan. Methods: A total of 43 eyes of 43 patients were included in this prospective study. The central corneal thickness (CCT, anterior chamber depth (ACD, white-to-white distance (WTW, flat keratometry (K1, steep keratometry (K2, and mean keratometry (K values were randomly measured three times with each device by the same examiner. The intraclass correlation coefficient of repeatability was analyzed. The compatibility of both devices was evaluated using the 95% limits of the agreement proposed by Bland and Altman. Results: Examiner achieved high repeatability for all parameters on each device except the WTW measured by Sirius. All measurements except WTW and K1 taken with the Sirius were higher than that taken with the Nidek AL-Scan®. The difference in CCT, ACD, and WTW values was statistically significant. Conclusion: High repeatability of the measurements was achieved on both devices. Although Km, K1, and K2 measurements of the Sirius and the AL-Scan® showed good agreement, WTW, CCT, and ACD measurements significantly differed between two devices. Thus, anterior segment measurements except for Km, K1, and K2 cannot be used interchangeably between Sirius and Nidek AL-Scan® devices.

  3. The Impact of Anesthesia-Influenced Process Measure Compliance on Length of Stay: Results From an Enhanced Recovery After Surgery for Colorectal Surgery Cohort.

    Science.gov (United States)

    Grant, Michael C; Pio Roda, Claro M; Canner, Joseph K; Sommer, Philip; Galante, Daniel; Hobson, Deborah; Gearhart, Susan; Wu, Christopher L; Wick, Elizabeth

    2018-05-17

    Process measure compliance has been associated with improved outcomes in enhanced recovery after surgery (ERAS) programs. Herein, we sought to assess the impact of compliance with measures directly influenced by anesthesiology in an ERAS for colorectal surgery cohort. From January 2013 to April 2015, data from 1140 consecutive patients were collected for all patients before (pre-ERAS) and after (ERAS) implementation of an ERAS program. Compliance with 9 specific process measures directly influenced by the anesthesiologist or acute pain service was analyzed to determine the impact on hospital length of stay (LOS). Process measure compliance was associated with a stepwise reduction in LOS. Patients who received >4 process measures (high compliance) had a significantly shorter LOS (incident rate ratio [IRR], 0.77; 95% CI, 0.70-0.85); P process measures) counterparts. Multivariable regression suggests that utilization of multimodal nausea and vomiting prophylaxis (IRR, 0.78; 95% CI, 0.68-0.89; P process measures directly influenced by the anesthesiologists and in concert with a formal anesthesia protocol is associated with reduced LOS. Engaging anesthesiology colleagues throughout the surgical encounter increases the overall value of perioperative care.

  4. Is routine transvaginal cervical length measurement cost-effective in a population where the risk of spontaneous preterm birth is low?

    Science.gov (United States)

    Crosby, David A; Miletin, Jan; Semberova, Jana; Daly, Sean

    2016-12-01

    A recent meta-analysis has suggested that routine measurement of the cervical length should be performed in conjunction with the anomaly scan to identify a group of women at increased risk of preterm delivery. We decided to investigate whether this recommendation is justifiable in a population where the risk of preterm birth is low. We reviewed 12 years of obstetric data from the Coombe Women and Infants University Hospital. Relative risks of adverse outcomes from the randomized controlled trial were applied and we extrapolated the possible numbers of women requiring intervention. We then used published neonatal data to estimate the cost of neonatal care and estimated the costs of providing the service. Over 12 years from 2000 until 2011, there were 94 646 singleton deliveries, 1776 happening before 34 weeks. Spontaneous onset occurred in 882 (49.7%) of this group. These 882 births were studied. If we apply the figures from a randomized controlled trial, 1609 women (1.7% from our total population) would be expected to have a cervical length 15 mm. If we gave vaginal progesterone to all women with a sonographically short cervix, we would reduce the delivery rate before 34 weeks by 27.7%. The annual costs of providing the service were estimated to be €109 249 and the cost of immediate neonatal care was estimated to be €380 514. Given the implications associated with preterm delivery, routine measurement of cervical length at the time of the anomaly scan may be justifiable from a cost point of view in a population where the risk of preterm birth is low. © 2016 Nordic Federation of Societies of Obstetrics and Gynecology.

  5. MARBLE (Multiple Antenna Radio-interferometry for Baseline Length Evaluation): Development of a Compact VLBI System for Calibrating GNSS and Electronic Distance Measurement Devices

    Science.gov (United States)

    Ichikawa, R.; Ishii, A.; Takiguchi, H.; Kimura, M.; Sekido, M.; Takefuji, K.; Ujihara, H.; Hanado, Y.; Koyama, Y.; Kondo, T.; Kurihara, S.; Kokado, K.; Kawabata, R.; Nozawa, K.; Mukai, Y.; Kuroda, J.; Ishihara, M.; Matsuzaka, S.

    2012-12-01

    We are developing a compact VLBI system with a 1.6-m diameter aperture dish in order to provide reference baseline lengths for calibration. The reference baselines are used to validate surveying instruments such as GPS and EDM and is maintained by the Geospatial Information Authority of Japan (GSI). The compact VLBI system will be installed at both ends of the reference baseline. Since the system is not sensitive enough to detect fringes between the two small dishes, we have designed a new observation concept including one large dish station. We can detect two group delays between each compact VLBI system and the large dish station based on conventional VLBI measurement. A group delay between the two compact dishes can be indirectly calculated using a simple equation. We named the idea "Multiple Antenna Radio-interferometry for Baseline Length Evaluation", or MARBLE system. The compact VLBI system is easy transportable and consists of the compact dish, a new wide-band front-end system, azimuth and elevation drive units, an IF down-converter unit, an antenna control unit (ACU), a counterweight, and a monument pillar. Each drive unit is equipped with a zero-backlash harmonic drive gearing component. A monument pillar is designed to mount typical geodetic GNSS antennas easily and an offset between the GNSS antenna reference point. The location of the azimuth-elevation crossing point of the VLBI system is precisely determined with an uncertainty of less than 0.2 mm. We have carried out seven geodetic VLBI experiments on the Kashima-Tsukuba baseline (about 54 km) using the two prototypes of the compact VLBI system between December 2009 and December 2010. The average baseline length and repeatability of the experiments is 54184874.0 ± 2.4 mm. The results are well consistent with those obtained by GPS measurements. In addition, we are now planning to use the compact VLBI system for precise time and frequency comparison between separated locations.

  6. Influence of detomidine on atrial fibrillation cycle length measured by intracardiac electrogram recording and by colour tissue Doppler imaging in horses.

    Science.gov (United States)

    Decloedt, A; de Clercq, D; van der Vekens, N; Verheyen, T; Ven, S; van Loon, G

    2016-01-01

    Shortening of atrial fibrillation cycle length (AFCL) is a marker of atrial electrical remodelling due to atrial fibrillation (AF). To investigate the effect of administration of detomidine on AFCL measured invasively from an intra-atrial electrogram (AFCLEGM) and noninvasively by tissue Doppler imaging (AFCLTDI). We hypothesised that detomidine would have no effect on AFCL but would improve the ease of TDI measurements and facilitate noninvasive AFCL determination. Prospective clinical study. Measurements were performed before and after i.v. administration of 7.5 μg/kg bwt detomidine in 33 episodes of AF in 32 horses (582 ± 64 kg bwt, 10 ± 3 years old) referred for electrical cardioversion. The AFCLEGM was measured from a right atrial intracardiac electrogram. The AFCLTDI was measured from atrial colour tissue velocity curves in 5 atrial wall regions. Mean AFCLEGM and AFCLTDI without and with sedation were compared using a repeated-measures linear mixed model with Bonferroni correction for multiple comparisons and calculation of the Bland-Altman mean bias and limits of agreement between AFCLEGM and AFCLTDI. The mean AFCL was significantly increased after sedation, but this increase was very small (mean difference +4 ms). For AFCLTDI measurements, sedation significantly improved the quality of the atrial myocardial velocity curves and the number of AF cycles that could be measured per cardiac cycle. The Bland-Altman bias between AFCLEGM without sedation and AFCLTDI with sedation ranged from -18 to +15 ms depending on wall region. Bland-Altman limits of agreement were similar between AFCLEGM without sedation and AFCLTDI without and with sedation. Therefore, noninvasive AFCLTDI measurements with sedation can be used to estimate the atrial fibrillatory rate. Sedation facilitates noninvasive AFCL measurements but causes a slight increase in AFCL. Noninvasive AFCL measurements can be used as an indicator of atrial electrical remodelling, to study AF

  7. The influence of NDT-Bobath and PNF methods on the field support and total path length measure foot pressure (COP) in patients after stroke.

    Science.gov (United States)

    Krukowska, Jolanta; Bugajski, Marcin; Sienkiewicz, Monika; Czernicki, Jan

    In stroke patients, the NDT - (Bobath - Neurodevelopmental Treatment) and PNF (Proprioceptive Neuromuscular Facilitation) methods are used to achieve the main objective of rehabilitation, which aims at the restoration of maximum patient independence in the shortest possible period of time (especially the balance of the body). The aim of the study is to evaluate the effect of the NDT-Bobath and PNF methods on the field support and total path length measure foot pressure (COP) in patients after stroke. The study included 72 patients aged from 20 to 69 years after ischemic stroke with Hemiparesis. The patients were divided into 4 groups by a simple randomization. The criteria for this division were: the body side (right or left) affected by paresis and the applied rehabilitation methods. All the patients were applied the recommended kinesitherapeutic method (randomized), 35 therapy sessions, every day for a period of six weeks. Before initiation of therapy and after 6 weeks was measured the total area of the support and path length (COP (Center Of Pressure) measure foot pressure) using stabilometer platform - alpha. The results were statistically analyzed. After treatment studied traits decreased in all groups. The greatest improvement was obtained in groups with NDT-Bobath therapy. NDT-Bobath method for improving the balance of the body is a more effective method of treatment in comparison with of the PNF method. In stroke patients, the effectiveness of NDT-Bobath method does not depend on hand paresis. Copyright © 2016 Polish Neurological Society. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  8. Measurement of the diffusion length of thermal neutrons in the beryllium oxide; Mesure de la longueur de diffusion des neutrons thermiques dans l'oxyde de beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Koechlin, J C; Martelly, J; Duggal, V P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1955-07-01

    The diffusion length of thermal neutrons in the beryllium oxide has been obtained while studying the spatial distribution of the neutrons in a massive parallelepiped of this matter placed before the thermal column of the reactor core of Saclay. The mean density of the beryllium oxide (BeO) is 2,95 gr/cm{sup 3}, the mean density of the massif is 2,92 gr/cm{sup 3}. The value of the diffusion length, deducted of the done measures, is: L = 32,7 {+-} 0,5 cm (likely gap). Some remarks are formulated about the influence of the spectral distribution of the neutrons flux used. (authors) [French] La longueur de diffusion des neutrons thermiques dans l'oxyde de beryllium a ete obtenue en etudiant la repartition spatiale des neutrons dans un massif parallelepipedique de cette matiere placee devant la colonne thermique de la Pile de Saclay. La densite moyenne de l'oxyde de beryllium (BeO) est de 2,95 gr/cm{sup 3}, la densite moyenne du massif de 2,92 gr/cm{sup 3}. La valeur de la longueur de diffusion, deduite des mesures effectuees est: L 32,7 {+-} 0,5 cm (ecart probable). Des remarques sont formulees quant a l'influence de la repartition spectrale du flux de neutrons utilise. (auteurs)

  9. First-trimester screening in pregnancies conceived by assisted reproductive technology: significance of gestational dating by oocyte retrieval or sonographic measurement of crown-rump length

    DEFF Research Database (Denmark)

    Gjerris, A.C.; Loft, A.; Pinborg, A.

    2008-01-01

    OBJECTIVES: To evaluate, in pregnancies conceived by assisted reproductive technology, whether determination of gestational age (GA) by date of oocyte aspiration (DOA) or crown-rump length (CRL) at first-trimester screening influences the distribution of serum and sonographic markers or the perfo......OBJECTIVES: To evaluate, in pregnancies conceived by assisted reproductive technology, whether determination of gestational age (GA) by date of oocyte aspiration (DOA) or crown-rump length (CRL) at first-trimester screening influences the distribution of serum and sonographic markers...... or the performance of first-trimester screening for chromosomal abnormalities. METHODS: GA was calculated using either DOA or CRL at blood sampling and nuchal translucency thickness (NT) measurement in 729 singleton pregnancies conceived by in-vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI......). Weight-corrected log multiples of the median (MoM) marker distributions specific for IVF pregnancy were established using multiple log regression and compared for DOA- and CRL-based GA calculation. RESULTS: GA determined by CRL was significantly larger, albeit slightly, than was GA determined by DOA...

  10. Correspondence optimization in 2D standardized carotid wall thickness map by description length minimization: A tool for increasing reproducibility of 3D ultrasound-based measurements.

    Science.gov (United States)

    Chen, Yimin; Chiu, Bernard

    2016-12-01

    The previously described 2D standardized vessel-wall-plus-plaque thickness (VWT) maps constructed from 3D ultrasound vessel wall measurements using an arc-length (AL) scaling approach adjusted the geometric variability of carotid arteries and has allowed for the comparisons of VWT distributions in longitudinal and cross-sectional studies. However, this mapping technique did not optimize point correspondence of the carotid arteries investigated. The potential misalignment may lead to errors in point-wise VWT comparisons. In this paper, we developed and validated an algorithm based on steepest description length (DL) descent to optimize the point correspondence implied by the 2D VWT maps. The previously described AL approach was applied to obtain initial 2D maps for a group of carotid arteries. The 2D maps were reparameterized based on an iterative steepest DL descent approach, which consists of the following two steps. First, landmarks established by resampling the 2D maps were aligned using the Procrustes algorithm. Then, the gradient of the DL with respect to horizontal and vertical reparameterizations of each landmark on the 2D maps was computed, and the 2D maps were subsequently deformed in the direction of the steepest descent of DL. These two steps were repeated until convergence. The quality of the correspondence was evaluated in a phantom study and an in vivo study involving ten carotid arteries enrolled in a 3D ultrasound interscan variability study. The correspondence quality was evaluated in terms of the compactness and generalization ability of the statistical shape model built based on the established point correspondence in both studies. In the in vivo study, the effect of the proposed algorithm on interscan variability of VWT measurements was evaluated by comparing the percentage of landmarks with statistically significant VWT-change before and after point correspondence optimization. The statistical shape model constructed with optimized

  11. Measurement of Pion and Proton Response and Longitudinal Shower Profiles up to 20 Nuclear Interaction Lengths with the ATLAS Tile Calorimeter

    CERN Document Server

    Adragna, P; Anderson, K; Antonaki, A; Arabidze, A; Batkova, L; Batusov, V; Beck, H P; Bergeaas Kuutmann, E; Biscarat, C; Blanchot, G; Bogush, A; Bohm, C; Boldea, V; Bosman, M; Bromberg, C; Budagov, J; Burckhart-Chromek, D; Caprini, M; Caloba, L; Calvet, D; Carli, T; Carvalho, J; Cascella, M; Castelo, J; Castillo, M V; Cavalli-Sforza, M; Cavasinni, V; Cerqueira, A S; Clement, C; Cobal, M; Cogswell, F; Constantinescu, S; Costanzo, D; Corso-Radu, A; Cuenca, C; Damazio, D O; Davidek, T; De, K; Del Prete, T; Di Girolamo, B; Dita, S; Djobava, T; Dobson, M; Dotti, A; Downing, R; Efthymiopoulos, I; Eriksson, D; Errede, D; Errede, S; Farbin, A; Fassouliotis, D; Febbraro, R; Fenyuk, A; Ferdi, C; Ferrer, A; Flaminio, V; Francis, D; Fullana, E; Gadomski, S; Gameiro, S; Garde, V; Gellerstedt, K; Giakoumopoulou, V; Gildemeister, O; Gilewsky, V; Giokaris, N; Gollub, N; Gomes, A; Gonzalez, V; Gorini, B; Grenier, P; Gris, P; Gruwe, M; Guarino, V; Guicheney, C; Gupta, A; Haeberli, C; Hakobyan, H; Haney, M; Hellman, S; Henriques, A; Higon, E; Holmgren, S; Hurwitz, M; Huston, J; Iglesias, C; Isaev, A; Jen-La Plante, I; Jon-And, K; Joos, M; Junk, T; Karyukhin, A; Kazarov, A; Khandanyan, H; Khramov, J; Khubua, J; Kolos, S; Korolkov, I; Krivkova, P; Kulchitsky, Y; Kurochkin, Yu; Kuzhir, P; LeCompte, T; Lefevre, R; Lehmann, G; Leitner, R; Lembesi, M; Lesser, J; Li, J; Liablin, M; Lokajicek, M; Lomakin, Y; Lupi, A; Maidanchik, C; Maio, A; Makouski, M; Maliukov, S; Manousakis, A; Mapelli, L; Marques, C; Marroquim, F; Martin, F; Mazzoni, E; Merritt, F; Miagkov, A; Miller, R; Minashvili, I; Miralles, L; Montarou, G; Mosidze, M; Myagkov, A; Nemecek, S; Nessi, M; Nodulman, L; Nordkvist, B; Norniella, O; Novakova, J; Onofre, A; Oreglia, M; Pallin, D; Pantea, D; Petersen, J; Pilcher, J; Pina, J; Pinhao, J; Podlyski, F; Portell Bueso, X; Poveda, J; Pribyl, L; Price, L E; Proudfoot, J; Ramstedt, M; Richards, R; Roda, C; Romanov, V; Rosnet, P; Roy, P; Ruiz, A; Rumiantsev, V; Russakovich, N; Salto, O; Salvachua, B; Sanchis, E; Sanders, H; Santoni, C; Saraiva, J G; Sarri, F; Satsunkevitch, I; Says, L P; Schlager, G; Schlereth, J; Seixas, J M; Sellden, B; Shalanda, N; Shevtsov, P; Shochet, M; Silva, J; Da Silva, P; Simaitis, V; Simonyan, M; Sissakian, A; Sjolin, J; Solans, C; Solodkov, A; Soloviev, I; Solovyanov, O; Sosebee, M; Spano, F; Stanek, R; Starchenko, E; Starovoitov, P; Stavina, P; Suk, M; Sykora, I; Tang, F; Tas, P; Teuscher, R; Tokar, S; Topilin, N; Torres, J; Tremblet, L; Tsiareshka, P; Tylmad, M; Underwood, D; Unel, G; Usai, G; Valero, A; Valkar, S; Valls, J A; Vartapetian, A; Vazeille, F; Vichou, I; Vinogradov, V; Vivarelli, I; Volpi, M; White, A; Zaitsev, A; Zenine, A; Zenis, T

    2010-01-01

    The response of pions and protons in the energy range of 20 to 180 GeV produced at CERN's SPS H8 test beam line in the ATLAS iron-scintillator Tile hadron calorimeter has been measured. The test-beam configuration allowed to measure the longitudinal shower development for pions and protons up to 20 nuclear interaction lengths. It is found that pions penetrate deeper in the calorimeter than protons. However, protons induce showers that are wider laterally to the direction of the impinging particle. Including the measured total energy response, the pion to proton energy ratio and the resolution, all observations are consistent with a higher electromagnetic energy fraction in pion induced showers. The data are compared with GEANT4 simulations using several hadronic physics lists. The measured longitudinal shower profiles are described by an analytical shower parameterization within an accuracy of 5-10%. The amount of energy leaking out behind the calorimeter is determined and parameterised as a function of the b...

  12. Comparison of anterior segment parameters and axial length measurements performed on a Scheimpflug device with biometry function and a reference optical biometer.

    Science.gov (United States)

    Muzyka-Woźniak, Maria; Oleszko, Adam

    2018-04-26

    To compare measurements of axial length (AL), corneal curvature (K), anterior chamber depth (ACD) and white-to-white (WTW) distance on a new device combining Scheimpflug camera and partial coherence interferometry (Pentacam AXL) with a reference optical biometer (IOL Master 500). To evaluate differences between IOL power calculations based on the two biometers. Ninety-seven eyes of 97 consecutive cataract or refractive lens exchange patients were examined preoperatively on IOL Master 500 and Pentacam AXL units. Comparisons between two devices were performed for AL, K, ACD and WTW. Intraocular lens (IOL) power targeting emmetropia was calculated with SRK/T and Haigis formulas on both devices and compared. There were statistically significant differences between two devices for all measured parameters (P eyes for Haigis formula and in 62% of eyes for SRK/T formula, with a mean difference within ± 0.5 D for 72 and 86% of eyes, respectively. There were statistically significant differences between AL, K and WTW measurements obtained with the compared biometers. Flatter corneal curvature measurements on Pentacam AXL necessitate formulas optimisation for Pentacam AXL.

  13. Measurement of pion and proton response and longitudinal shower profiles up to 20 nuclear interaction lengths with the ATLAS Tile calorimeter

    Energy Technology Data Exchange (ETDEWEB)

    Adragna, P [Pisa University and INFN, Pisa (Italy); Alexa, C [National Institute for Physics and Nuclear Engineering, Bucharest (Romania); Anderson, K [University of Chicago, Chicago, IL (United States); Antonaki, A; Arabidze, A [University of Athens, Athens (Greece); Batkova, L [Comenius University, Bratislava (Slovakia); Batusov, V [JINR, Dubna (Russian Federation); Beck, H P [Laboratory for High Energy Physics, University of Bern (Switzerland); Bergeaas Kuutmann, E [Stockholm University, Stockholm (Sweden); Biscarat, C [LPC Clermont-Ferrand, Universite Blaise Pascal, Clermont-Ferrand (France); Blanchot, G [CERN, Geneva (Switzerland); Bogush, A [Institute of Physics, National Academy of Sciences, Minsk (Belarus); Bohm, C [Stockholm University, Stockholm (Sweden); Boldea, V [National Institute for Physics and Nuclear Engineering, Bucharest (Romania); Bosman, M [Institut de Fisica d' Altes Energies, Universitat Autonoma de Barcelona, Barcelona (Spain); Bromberg, C [Michigan State University, East Lansing, MI (United States); Budagov, J [JINR, Dubna (Russian Federation); Burckhart-Chromek, D [CERN, Geneva (Switzerland); Caprini, M [National Institute for Physics and Nuclear Engineering, Bucharest (Romania); Caloba, L [COPPE/EE/UFRJ, Rio de Janeiro (Brazil)

    2010-04-01

    The response of pions and protons in the energy range of 20-180 GeV, produced at CERN's SPS H8 test-beam line in the ATLAS iron-scintillator Tile hadron calorimeter, has been measured. The test-beam configuration allowed the measurement of the longitudinal shower development for pions and protons up to 20 nuclear interaction lengths. It was found that pions penetrate deeper in the calorimeter than protons. However, protons induce showers that are wider laterally to the direction of the impinging particle. Including the measured total energy response, the pion-to-proton energy ratio and the resolution, all observations are consistent with a higher electromagnetic energy fraction in pion-induced showers. The data are compared with GEANT4 simulations using several hadronic physics lists. The measured longitudinal shower profiles are described by an analytical shower parametrization within an accuracy of 5-10%. The amount of energy leaking out behind the calorimeter is determined and parametrized as a function of the beam energy and the calorimeter depth. This allows for a leakage correction of test-beam results in the standard projective geometry.

  14. Measurement of pion and proton response and longitudinal shower profiles up to 20 nuclear interaction lengths with the ATLAS Tile calorimeter

    International Nuclear Information System (INIS)

    Adragna, P.; Alexa, C.; Anderson, K.; Antonaki, A.; Arabidze, A.; Batkova, L.; Batusov, V.; Beck, H.P.; Bergeaas Kuutmann, E.; Biscarat, C.; Blanchot, G.; Bogush, A.; Bohm, C.; Boldea, V.; Bosman, M.; Bromberg, C.; Budagov, J.; Burckhart-Chromek, D.; Caprini, M.; Caloba, L.

    2010-01-01

    The response of pions and protons in the energy range of 20-180 GeV, produced at CERN's SPS H8 test-beam line in the ATLAS iron-scintillator Tile hadron calorimeter, has been measured. The test-beam configuration allowed the measurement of the longitudinal shower development for pions and protons up to 20 nuclear interaction lengths. It was found that pions penetrate deeper in the calorimeter than protons. However, protons induce showers that are wider laterally to the direction of the impinging particle. Including the measured total energy response, the pion-to-proton energy ratio and the resolution, all observations are consistent with a higher electromagnetic energy fraction in pion-induced showers. The data are compared with GEANT4 simulations using several hadronic physics lists. The measured longitudinal shower profiles are described by an analytical shower parametrization within an accuracy of 5-10%. The amount of energy leaking out behind the calorimeter is determined and parametrized as a function of the beam energy and the calorimeter depth. This allows for a leakage correction of test-beam results in the standard projective geometry.

  15. Measurements of attenuation lengths through concrete and iron for neutrons produced by 800-MeV proton on tantalum target at ISIS

    CERN Document Server

    Nunomiya, T; Wright, P; Nakamura, T; Kim, E; Kurosawa, T; Taniguchi, S; Sasaki, M; Iwase, H; Uwamino, Y; Shibata, T; Ito, S; Perry, D R

    2002-01-01

    A deep penetration experiment through a thick bulk shield was performed at an intense spallation neutron source facility, ISIS, of the Rutherford Appleton Laboratory (RAL), United Kingdom. ISIS is a 800 MeV-200 mu A proton accelerator facility. Neutrons are produced from a tantalum target, and are shielded with approximately 3-m thick steel and 1-m thick ordinary concrete. On top of the shield, we measured the neutron flux attenuation through concrete and iron shields, which were additionally placed up to 120-cm and 60-cm thickness, respectively, using activation detectors of graphite and bismuth. The attenuation lengths of concrete and iron for high-energy neutrons above 20 MeV were obtained from the sup 1 sup 2 C(n, 2n) sup 1 sup 1 C reaction of graphite.

  16. Lengths of Schwabe cycles in the seventh and eighth centuries indicated by precise measurement of carbon-14 content in tree rings

    Science.gov (United States)

    Miyake, Fusa; Masuda, Kimiaki; Nakamura, Toshio

    2013-12-01

    (14C) is produced in the atmosphere by galactic cosmic rays, which are modulated by solar magnetic activity. Its content in tree rings is retained and provides a record of past cosmic ray intensity and solar activity. We have measured, with 2 year resolution, the 14C content in Japanese cedar tree rings for the period A.D. 600 to 760, which includes a small grand solar minimum in the seventh to eighth centuries. Periodicity analysis of the 14C data shows that there is a component in the frequency band of the Schwabe cycle, with a period of 12-13 years continuing throughout the minimum. This is the fourth case in which an increase in the length of the Schwabe cycle has been observed in a grand solar minimum, after the Maunder Minimum, the Spörer Minimum, and the Fourth Century B.C. Minimum.

  17. Gender-based differences in stride and limb dimensions between healthy red-wing tinamou (Rhynchotus rufescens) Temminck, 1815

    OpenAIRE

    QUEIROZ, Sandra Aidar de; COOPER, Ross Gordon

    2014-01-01

    The red-wing tinamou (Rhynchotus rufescens) is economically important as food. The current study investigated the limb and trunk characteristics in age-matched [year-of-hatch (yoh) 2004 and 2005], gender segregated birds, and determined differences in stride between cocks and hens. The locomotion trial was completed in a corridor of 0.6 × 2.36 m dimension. The girth was significantly higher in cocks than in hens, while body weight was slightly higher in hens. Cocks had a greater height than h...

  18. Gender-based differences in stride and limb dimensions between healthy red-wing tinamou (Rhynchotus rufescens) Temminck, 1815

    OpenAIRE

    de Queiroz, Sandra Aidar [UNESP; Cooper, Ross Gordon

    2011-01-01

    The red-wing tinamou (Rhynchotus rufescens) is economically important as food. The current study investigated the limb and trunk characteristics in age-matched [year-of-hatch (yoh) 2004 and 2005], gender segregated birds, and determined differences in stride between cocks and hens. The locomotion trial was completed in a corridor of 0.6 x 2.36 m dimension. The girth was significantly higher in cocks than in hens, while body weight was slightly higher in hens. Cocks had a greater height than h...

  19. Maximum swimming speeds of sailfish and three other large marine predatory fish species based on muscle contraction time and stride length

    DEFF Research Database (Denmark)

    Svendsen, Morten Bo Søndergaard; Domenici, Paolo; Marras, Stefano

    2016-01-01

    Billfishes are considered to be among the fastest swimmers in the oceans. Previous studies have estimated maximum speed of sailfish and black marlin at around 35 m s(-1) but theoretical work on cavitation predicts that such extreme speed is unlikely. Here we investigated maximum speed of sailfish...

  20. First-Trimester Crown-Rump Length and Embryonic Volume of Fetuses with Structural Congenital Abnormalities Measured in Virtual Reality: An Observational Study

    Directory of Open Access Journals (Sweden)

    L. Baken

    2017-01-01

    Full Text Available Background. With the introduction of three-dimensional (3D ultrasound it has become possible to measure volumes. The relative increase in embryonic volume (EV is much larger than that of the crown-rump length (CRL over the same time period. We examined whether EV is a better parameter to determine growth restriction in fetuses with structural congenital abnormalities. Study Design, Subjects, and Outcome Measures. CRL and EV were measured using a Virtual Reality (VR system in prospectively collected 3D ultrasound volumes of 56 fetuses diagnosed with structural congenital abnormalities in the first trimester of pregnancy (gestational age 7+5 to 14+5 weeks. Measured CRL and EV were converted to z-scores and to percentages of the expected mean using previously published reference curves of euploid fetuses. The one-sample t-test was performed to test significance. Results. The EV was smaller than expected for GA in fetuses with structural congenital abnormalities (−35%  p<0.001, z-score −1.44  p<0.001, whereas CRL was not (−6.43%  p=0.118, z-score −0.43  p=0.605. Conclusions. CRL is a less reliable parameter to determine growth restriction in fetuses with structural congenital abnormalities as compared with EV. By measuring EV, growth restriction in first-trimester fetuses with structural congenital abnormalities becomes more evident and enables an earlier detection of these cases.

  1. A novel method for patient exit and entrance dose prediction based on water equivalent path length measured with an amorphous silicon electronic portal imaging device

    Science.gov (United States)

    Kavuma, Awusi; Glegg, Martin; Metwaly, Mohamed; Currie, Garry; Elliott, Alex

    2010-01-01

    In vivo dosimetry is one of the quality assurance tools used in radiotherapy to monitor the dose delivered to the patient. Electronic portal imaging device (EPID) images for a set of solid water phantoms of varying thicknesses were acquired and the data fitted onto a quadratic equation, which relates the reduction in photon beam intensity to the attenuation coefficient and material thickness at a reference condition. The quadratic model is used to convert the measured grey scale value into water equivalent path length (EPL) at each pixel for any material imaged by the detector. For any other non-reference conditions, scatter, field size and MU variation effects on the image were corrected by relative measurements using an ionization chamber and an EPID. The 2D EPL is linked to the percentage exit dose table, for different thicknesses and field sizes, thereby converting the plane pixel values at each point into a 2D dose map. The off-axis ratio is corrected using envelope and boundary profiles generated from the treatment planning system (TPS). The method requires field size, monitor unit and source-to-surface distance (SSD) as clinical input parameters to predict the exit dose, which is then used to determine the entrance dose. The measured pixel dose maps were compared with calculated doses from TPS for both entrance and exit depth of phantom. The gamma index at 3% dose difference (DD) and 3 mm distance to agreement (DTA) resulted in an average of 97% passing for the square fields of 5, 10, 15 and 20 cm. The exit dose EPID dose distributions predicted by the algorithm were in better agreement with TPS-calculated doses than phantom entrance dose distributions.

  2. Sample Length Affects the Reliability of Language Sample Measures in 3-Year-Olds: Evidence from Parent-Elicited Conversational Samples

    Science.gov (United States)

    Guo, Ling-Yu; Eisenberg, Sarita

    2015-01-01

    Purpose: The goal of this study was to investigate the extent to which sample length affected the reliability of total number of words (TNW), number of different words (NDW), and mean length of C-units in morphemes (MLCUm) in parent-elicited conversational samples for 3-year-olds. Method: Participants were sixty 3-year-olds. A 22-min language…

  3. Telomere Length and Mortality

    DEFF Research Database (Denmark)

    Kimura, Masayuki; Hjelmborg, Jacob V B; Gardner, Jeffrey P

    2008-01-01

    Leukocyte telomere length, representing the mean length of all telomeres in leukocytes, is ostensibly a bioindicator of human aging. The authors hypothesized that shorter telomeres might forecast imminent mortality in elderly people better than leukocyte telomere length. They performed mortality...

  4. Odd Length Contraction

    Science.gov (United States)

    Smarandache, Florentin

    2013-09-01

    Let's denote by VE the speed of the Earth and byVR the speed of the rocket. Both travel in the same direction on parallel trajectories. We consider the Earth as a moving (at a constant speed VE -VR) spacecraft of almost spherical form, whose radius is r and thus the diameter 2r, and the rocket as standing still. The non-proper length of Earth's diameter, as measured by the astronaut is: L = 2 r√{ 1 -|/VE -VR|2 c2 } rocket! Also, let's assume that the astronaut is laying down in the direction of motion. Therefore, he would also shrink, or he would die!

  5. discouraged by queue length

    Directory of Open Access Journals (Sweden)

    P. R. Parthasarathy

    2001-01-01

    Full Text Available The transient solution is obtained analytically using continued fractions for a state-dependent birth-death queue in which potential customers are discouraged by the queue length. This queueing system is then compared with the well-known infinite server queueing system which has the same steady state solution as the model under consideration, whereas their transient solutions are different. A natural measure of speed of convergence of the mean number in the system to its stationarity is also computed.

  6. Calculation of exit dose for conformal and dynamically‐wedged fields, based on water‐equivalent path length measured with an amorphous silicon electronic portal imaging device

    Science.gov (United States)

    Glegg, Martin; Metwaly, Mohamed; Currie, Garry; Elliott, Alex

    2011-01-01

    In this study, we use the quadratic calibration method (QCM), in which an EPID image is converted into a matrix of equivalent path lengths (EPLs) and, therefore, exit doses, so as to model doses in conformal and enhanced dynamic wedge (EDW) fields. The QCM involves acquiring series of EPID images at a reference field size for different thicknesses of homogeneous solid water blocks. From these, a set of coefficients is established that is used to compute the EPL of any other irradiated material. To determine the EPL, the irradiated area must be known in order to establish the appropriate scatter correction. A method was devised for the automatic calculation of areas from the EPID image that facilitated the calculation of EPL for any field and exit dose. For EDW fields, the fitting coefficients were modified by utilizing the linac manufacturer's golden segmented treatment tables (GSTT) methodology and MU fraction model. The nonlinear response of the EPL with lower monitor units (MUs) was investigated and slight modification of the algorithm performed to account for this. The method permits 2D dose distributions at the exit of phantom or patient to be generated by relating the EPL with an appropriate depth dose table. The results indicate that the inclusion of MU correction improved the EPL determination. The irradiated field areas can be accurately determined from EPID images to within ± 1% uncertainty. Cross‐plane profiles and 2D dose distributions of EPID predicted doses were compared with those calculated with the Eclipse treatment planning system (TPS) and those measured directly with MapCHECK 2 device. Comparison of the 2D EPID dose maps to those from TPS and MapCHECK shows that more than 90% of all points passed the gamma index acceptance criteria of 3% dose difference and 3 mm distance to agreement (DTA), for both conformal and EDW study cases. We conclude that the EPID QCM is an accurate and convenient method for in vivo dosimetry and may, therefore

  7. Effect of trotting speed on kinematic variables measured by use of extremity-mounted inertial measurement units in nonlame horses performing controlled treadmill exercise.

    Science.gov (United States)

    Cruz, Antonio M; Vidondo, Beatriz; Ramseyer, Alessandra A; Maninchedda, Ugo E

    2018-02-01

    OBJECTIVE To assess effects of speed on kinematic variables measured by use of extremity-mounted inertial measurement units (IMUs) in nonlame horses performing controlled exercise on a treadmill. ANIMALS 10 nonlame horses. PROCEDURES 6 IMUs were attached at predetermined locations on 10 nonlame Franches Montagnes horses. Data were collected in triplicate during trotting at 3.33 and 3.88 m/s on a high-speed treadmill. Thirty-three selected kinematic variables were analyzed. Repeated-measures ANOVA was used to assess the effect of speed. RESULTS Significant differences between the 2 speeds were detected for most temporal (11/14) and spatial (12/19) variables. The observed spatial and temporal changes would translate into a gait for the higher speed characterized by increased stride length, protraction and retraction, flexion and extension, mediolateral movement of the tibia, and symmetry, but with similar temporal variables and a reduction in stride duration. However, even though the tibia coronal range of motion was significantly different between speeds, the high degree of variability raised concerns about whether these changes were clinically relevant. For some variables, the lower trotting speed apparently was associated with more variability than was the higher trotting speed. CONCLUSIONS AND CLINICAL RELEVANCE At a higher trotting speed, horses moved in the same manner (eg, the temporal events investigated occurred at the same relative time within the stride). However, from a spatial perspective, horses moved with greater action of the segments evaluated. The detected changes in kinematic variables indicated that trotting speed should be controlled or kept constant during gait evaluation.

  8. Comparison of Birth-and Conception-Based Definitions of Postnatal Age in Developmental and Reproductive Rodent Toxicity Studies: lnfluence of Gestation Length on Measurements of Offspring Body Weight and Puberty in Controls

    Science.gov (United States)

    Most laboratories conducting developmental and reproductive toxicity studies in rodents assign age by defining postnatal day (PND) 0 or 1 as the day of birth (DOB); i.e., gestation length affects PND and the timing of postnatal measurements. Some laboratories, however, define age...

  9. Measurement of the Length of Installed Rock Bolt Based on Stress Wave Reflection by Using a Giant Magnetostrictive (GMS) Actuator and a PZT Sensor.

    Science.gov (United States)

    Luo, Mingzhang; Li, Weijie; Wang, Bo; Fu, Qingqing; Song, Gangbing

    2017-02-23

    Rock bolts, as a type of reinforcing element, are widely adopted in underground excavations and civil engineering structures. Given the importance of rock bolts, the research outlined in this paper attempts to develop a portable non-destructive evaluation method for assessing the length of installed rock bolts for inspection purposes. Traditionally, piezoelectric elements or hammer impacts were used to perform non-destructive evaluation of rock bolts. However, such methods suffered from many major issues, such as the weak energy generated and the requirement for permanent installation for piezoelectric elements, and the inconsistency of wave generation for hammer impact. In this paper, we proposed a portable device for the non-destructive evaluation of rock bolt conditions based on a giant magnetostrictive (GMS) actuator. The GMS actuator generates enough energy to ensure multiple reflections of the stress waves along the rock bolt and a lead zirconate titantate (PZT) sensor is used to detect the reflected waves. A new integrated procedure that involves correlation analysis, wavelet denoising, and Hilbert transform was proposed to process the multiple reflection signals to determine the length of an installed rock bolt. The experimental results from a lab test and field tests showed that, by analyzing the instant phase of the periodic reflections of the stress wave generated by the GMS transducer, the length of an embedded rock bolt can be accurately determined.

  10. Mature clustered, regularly interspaced, short palindromic repeats RNA (crRNA) length is measured by a ruler mechanism anchored at the precursor processing site.

    Science.gov (United States)

    Hatoum-Aslan, Asma; Maniv, Inbal; Marraffini, Luciano A

    2011-12-27

    Precise RNA processing is fundamental to all small RNA-mediated interference pathways. In prokaryotes, clustered, regularly interspaced, short palindromic repeats (CRISPR) loci encode small CRISPR RNAs (crRNAs) that protect against invasive genetic elements by antisense targeting. CRISPR loci are transcribed as a long precursor that is cleaved within repeat sequences by CRISPR-associated (Cas) proteins. In many organisms, this primary processing generates crRNA intermediates that are subject to additional nucleolytic trimming to render mature crRNAs of specific lengths. The molecular mechanisms underlying this maturation event remain poorly understood. Here, we defined the genetic requirements for crRNA primary processing and maturation in Staphylococcus epidermidis. We show that changes in the position of the primary processing site result in extended or diminished maturation to generate mature crRNAs of constant length. These results indicate that crRNA maturation occurs by a ruler mechanism anchored at the primary processing site. We also show that maturation is mediated by specific cas genes distinct from those genes involved in primary processing, showing that this event is directed by CRISPR/Cas loci.

  11. The effects of surgical lengthening of hamstring muscles in children with cerebral palsy--the consequences of pre-operative muscle length measurement.

    Science.gov (United States)

    Laracca, Ettore; Stewart, Caroline; Postans, Neil; Roberts, Andrew

    2014-03-01

    Children with cerebral palsy often undergo multiple orthopaedic surgical procedures in a single episode. Evidence of the effectiveness of individual components within the overall package is sparse. The introduction of musculoskeletal modelling in Oswestry has led to a more conservative management approach being taken with hamstring muscles for children walking in a degree of crouch. Muscles which were shown to be of at least normal length at initial contact were not surgically lengthened, as would have been the case previously. A retrospective review of 30 such patients was therefore possible, comparing 15 patients treated before the policy change who had their hamstrings lengthened with 15 treated after who did not. All patients had pre and post operative gait assessments and significant changes were observed for each group separately and for the two groups when compared. The comparison revealed that preserving the hamstrings does tend to reduce, and therefore normalize, the dynamic muscle length. Examination of the two patient groups separately, however, reveals a more complex picture with more global gait improvements seen when the hamstrings were lengthened. No absolute recommendation can be made to inform the clinical management of all children with normal to long hamstring muscles during gait. The final decision of whether to include a hamstring lengthening will need to take into account the characteristics of the individual child. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Giant strides radurisation

    International Nuclear Information System (INIS)

    Basson, R.

    1986-01-01

    High Energy Processing (HEPRO) plans to establish a new commercial irradiation plant at Cape Town. Initially HEPRO experienced some problems when first established in 1982 at Tzaneen. This includes scepticism on the part of farmers as to wether radurised produce would command a sufficient mark-up to recover the treatment cost and the problem of motivating the retailers and wholesalers who purchase on the national fresh produce markets. A few of the large supermarket chains were eventually convinced to buy, radurised products. After periods of up to two years the chains are largely convinced of the advantages of radurisation. On 5 June 1985 HEPRO and the Atomic Energy Corporation of South Africa (AEC) signed an agreement according to which the AEC would design and manufacture all the equipment required for the new irradiation facility at Cape Town

  13. Direct measuring of single-cycle mid-IR light bullets path length in LiF by the laser coloration method

    Directory of Open Access Journals (Sweden)

    Chekalin Sergey

    2017-01-01

    Full Text Available A colour-centre structure formed in a LiF crystal under filamentation of a femtosecond mid-IR laser pulse with a power slightly exceeding the critical power for self-focusing has been experimentally and theoretically investigated. A single-cycle light bullet was recorded for the first time by observation of strictly periodic oscillations for the density of the color centers induced in an isotropic LiF crystal under filamentation of a laser beam with a wavelength tuned in the range from 2600 to 3900 nm, which is due to the periodic change in the light field amplitude in the light bullet formed under filamentation under propagation in dispersive medium. The light bullet path length was not more than one millimeter.

  14. Telomere length analysis.

    Science.gov (United States)

    Canela, Andrés; Klatt, Peter; Blasco, María A

    2007-01-01

    Most somatic cells of long-lived species undergo telomere shortening throughout life. Critically short telomeres trigger loss of cell viability in tissues, which has been related to alteration of tissue function and loss of regenerative capabilities in aging and aging-related diseases. Hence, telomere length is an important biomarker for aging and can be used in the prognosis of aging diseases. These facts highlight the importance of developing methods for telomere length determination that can be employed to evaluate telomere length during the human aging process. Telomere length quantification methods have improved greatly in accuracy and sensitivity since the development of the conventional telomeric Southern blot. Here, we describe the different methodologies recently developed for telomere length quantification, as well as their potential applications for human aging studies.

  15. Development and Validation of a Path Length Calculation for Carotid-Femoral Pulse Wave Velocity Measurement: A TASCFORCE, SUMMIT, and Caerphilly Collaborative Venture.

    Science.gov (United States)

    Weir-McCall, Jonathan R; Brown, Liam; Summersgill, Jennifer; Talarczyk, Piotr; Bonnici-Mallia, Michael; Chin, Sook C; Khan, Faisel; Struthers, Allan D; Sullivan, Frank; Colhoun, Helen M; Shore, Angela C; Aizawa, Kunihiko; Groop, Leif; Nilsson, Jan; Cockcroft, John R; McEniery, Carmel M; Wilkinson, Ian B; Ben-Shlomo, Yoav; Houston, J Graeme

    2018-05-01

    Current distance measurement techniques for pulse wave velocity (PWV) calculation are susceptible to intercenter variability. The aim of this study was to derive and validate a formula for this distance measurement. Based on carotid femoral distance in 1183 whole-body magnetic resonance angiograms, a formula was derived for calculating distance. This was compared with distance measurements in 128 whole-body magnetic resonance angiograms from a second study. The effects of recalculation of PWV using the new formula on association with risk factors, disease discrimination, and prediction of major adverse cardiovascular events were examined within 1242 participants from the multicenter SUMMIT study (Surrogate Markers of Micro- and Macrovascular Hard End-Points for Innovative Diabetes Tools) and 825 participants from the Caerphilly Prospective Study. The distance formula yielded a mean error of 7.8 mm (limits of agreement =-41.1 to 56.7 mm; P measurement, the distance formula did not change associations between PWV and age, blood pressure, or creatinine ( P accounting for differences in age, sex, and mean arterial pressure, intercenter differences in PWV persisted using the external distance measurement ( F =4.6; P =0.004), whereas there was a loss of between center difference using the distance formula ( F =1.4; P =0.24). PWV odds ratios for cardiovascular mortality remained the same using both the external distance measurement (1.14; 95% confidence interval, 1.06-1.24; P =0.001) and the distance formula (1.17; 95% confidence interval, 1.08-1.28; P measurement variability without impacting the diagnostic utility of carotid-femoral PWV. © 2018 The Authors.

  16. Analysis of ureteral length in adult cadavers

    Directory of Open Access Journals (Sweden)

    Hugo F. F. Novaes

    2013-04-01

    Full Text Available Introduction In some occasions, correlations between human structures can help planning surgical intra-abdominal interventions. The previous determination of ureteral length helps pre-operatory planning of surgeries, reduces costs of auxiliary exams, the correct choice of double-J catheter with low morbidity and fewer symptoms, and an adequate adhesion to treatment. Objective To evaluate ureteral length in adult cadavers and to analyze its correlation with anthropometric measures. Materials and Methods: From April 2009 to January 2012 we determined ureteral length of adult cadavers submitted to necropsy and obtained the following measures: height, distance from shoulder to wrist, elbow-wrist, xiphoid appendix-umbilicus, umbilicus-pubis, xiphoid appendix-pubis and between iliac spines. We analyzed the correlations between ureteral length and those anthropometric measures. Results We dissected 115 ureters from 115 adult corpses from April 2009 to January 2012. Median ureteral length didn't vary between sexes or according to height. It was observed no correlation among ureteral length and all considered anthropometric measures in all analyzed subgroups and in general population. There were no significant differences between right and left ureteral measures. Conclusions There is no difference of ureteral length in relation to height or gender (male or female. There is no significant correlation among ureteral length and the considered anthropometric measures.

  17. Effect of error in crack length measurement on maximum load fracture toughness of Zr-2.5Nb pressure tube material

    International Nuclear Information System (INIS)

    Bind, A.K.; Sunil, Saurav; Singh, R.N.; Chakravartty, J.K.

    2016-03-01

    Recently it was found that maximum load toughness (J max ) for Zr-2.5Nb pressure tube material was practically unaffected by error in Δ a . To check the sensitivity of the J max to error in Δ a measurement, the J max was calculated assuming no crack growth up to the maximum load (P max ) for as received and hydrogen charged Zr-2.5Nb pressure tube material. For load up to the P max , the J values calculated assuming no crack growth (J NC ) were slightly higher than that calculated based on Δ a measured using DCPD technique (JDCPD). In general, error in the J calculation found to be increased exponentially with Δ a . The error in J max calculation was increased with an increase in Δ a and a decrease in J max . Based on deformation theory of J, an analytic criterion was developed to check the insensitivity of the J max to error in Δ a . There was very good linear relation was found between the J max calculated based on Δ a measured using DCPD technique and the J max calculated assuming no crack growth. This relation will be very useful to calculate J max without measuring the crack growth during fracture test especially for irradiated material. (author)

  18. Roentgenologic investigations for the anterior tooth length

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Won Pyo; Ahn, Hyung Kyu [College of Dentistry, Seoul National University , Seoul (Korea, Republic of)

    1972-11-15

    The author measured the length of crown, root and tooth on the films which was taken by intraoral bisecting technic with mesh plate on the films. The films were taken from the dry skulls, dentiform, same patients who had to be removed their upper incisors, and the other patients who admitted for dental care. From this serial experiment the results were made as follows: 1. By using the film and mesh plate in the oral cavity, the real tooth length can be measured easily on the film surfaces. 2. The film distortion in the oral cavity can be avoided when taking the film using the mesh plate and film together. 3. When measuring the film, length of crown was elongated and length of root was shortened. 4. When using the well-trained bisecting technic, the real tooth length can be measured directly on the intraoral film.

  19. Measurement of the x-ray mass-attenuation coefficients of gold, derived quantities between 14 keV and 21 keV and determination of the bond lengths of gold

    International Nuclear Information System (INIS)

    Glover, J L; Chantler, C T; Barnea, Z; Rae, N A; Tran, C Q

    2010-01-01

    The x-ray mass-attenuation coefficients of gold are measured at 91 energies between 14 keV and 21 keV using synchrotron radiation. The measurements are accurate to between 0.08% and 0.1%. The photoelectric mass-absorption coefficients and the imaginary component of the form factors of gold are also determined. The results include the L I edge and are the most accurate and extensive gold dataset available in this energy range. An analysis of the L I edge XAFS showed excellent agreement between the measured and simulated XAFS and yielded highly accurate values of the bond lengths of gold. When our results are compared with earlier measurements and with predictions of major theoretical tabulations, significant discrepancies are noted. The comparison raises questions about the nature of discrepancies between experimental and theoretical values of mass-attenuation coefficients.

  20. Extended fuel cycle length

    International Nuclear Information System (INIS)

    Bruyere, M.; Vallee, A.; Collette, C.

    1986-09-01

    Extended fuel cycle length and burnup are currently offered by Framatome and Fragema in order to satisfy the needs of the utilities in terms of fuel cycle cost and of overall systems cost optimization. We intend to point out the consequences of an increased fuel cycle length and burnup on reactor safety, in order to determine whether the bounding safety analyses presented in the Safety Analysis Report are applicable and to evaluate the effect on plant licensing. This paper presents the results of this examination. The first part indicates the consequences of increased fuel cycle length and burnup on the nuclear data used in the bounding accident analyses. In the second part of this paper, the required safety reanalyses are presented and the impact on the safety margins of different fuel management strategies is examined. In addition, systems modifications which can be required are indicated

  1. Relativistic distances, sizes, lengths

    International Nuclear Information System (INIS)

    Strel'tsov, V.N.

    1992-01-01

    Such notion as light or retarded distance, field size, formation way, visible size of a body, relativistic or radar length and wave length of light from a moving atom are considered. The relation between these notions is cleared up, their classification is given. It is stressed that the formation way is defined by the field size of a moving particle. In the case of the electromagnetic field, longitudinal sizes increase proportionally γ 2 with growing charge velocity (γ is the Lorentz-factor). 18 refs

  2. Optical Arc-Length Sensor For TIG Welding

    Science.gov (United States)

    Smith, Matthew A.

    1990-01-01

    Proposed subsystem of tungsten/inert-gas (TIG) welding system measures length of welding arc optically. Viewed by video camera, in one of three alternative optical configurations. Length of arc measured instead of inferred from voltage.

  3. SU-C-207A-05: Feature Based Water Equivalent Path Length (WEPL) Determination for Proton Radiography by the Technique of Time Resolved Dose Measurement

    International Nuclear Information System (INIS)

    Zhang, R; Jee, K; Sharp, G; Flanz, J; Lu, H

    2016-01-01

    Purpose: Studies show that WEPL can be determined from modulated dose rate functions (DRF). However, the previous calibration method based on statistics of the DRF is sensitive to energy mixing of protons due to scattering through different materials (termed as range mixing here), causing inaccuracies in the determination of WEPL. This study intends to explore time-domain features of the DRF to reduce the effect of range mixing in proton radiography (pRG) by this technique. Methods: An amorphous silicon flat panel (PaxScan™ 4030CB, Varian Medical Systems, Inc., Palo Alto, CA) was placed behind phantoms to measure DRFs from a proton beam modulated by a specially designed modulator wheel. The performance of two methods, the previously used method based on the root mean square (RMS) and the new approach based on time-domain features of the DRF, are compared for retrieving WEPL and RSP from pRG of a Gammex phantom. Results: Calibration by T_8_0 (the time point for 80% of the major peak) was more robust to range mixing and produced WEPL with improved accuracy. The error of RSP was reduced from 8.2% to 1.7% for lung equivalent material, with the mean error for all other materials reduced from 1.2% to 0.7%. The mean error of the full width at half maximum (FWHM) of retrieved inserts was decreased from 25.85% to 5.89% for the RMS and T_8_0 method respectively. Monte Carlo simulations in simplified cases also demonstrated that the T_8_0 method is less sensitive to range mixing than the RMS method. Conclusion: WEPL images have been retrieved based on single flat panel measured DRFs, with inaccuracies reduced by exploiting time-domain features as the calibration parameter. The T_8_0 method is validated to be less sensitive to range mixing and can thus retrieve the WEPL values in proximity of interfaces with improved numerical and spatial accuracy for proton radiography.

  4. Evolução do comprimento cervical uterino na gestação, avaliado pela ultra-sonografia transvaginal Changes in cervical length during pregnancy measured by transvaginal ultrasound

    Directory of Open Access Journals (Sweden)

    Reginaldo Antônio de Oliveira Freitas-Júnior

    2003-03-01

    Full Text Available OBJETIVO: analisar a evolução do comprimento cervical uterino, ao longo da gestação, avaliado por meio da ultra-sonografia transvaginal. MÉTODOS: foi realizado estudo prospectivo, longitudinal, no qual 82 gestantes hígidas foram acompanhadas desde o início da gestação, das quais 49 mantiveram o seguimento até o parto sem complicações da gravidez, sendo examinadas a cada quatro semanas, e agrupadas, conforme a paridade, em nulíparas ou com um ou mais partos anteriores. O comprimento do colo uterino foi avaliado em vista sagital pela ultra-sonografia transvaginal, com a medida linear da distância entre os orifícios cervicais interno e externo. RESULTADOS: as médias de comprimento do colo uterino, bem como os percentis 5, 25, 50, 75 e 95, em função da idade gestacional, não diferiram significativamente entre os grupos estudados (p>0.05. No intervalo entre a 20ª e a 24ª semana gestacional o comprimento cervical variou entre 28, 35 e 47,2 mm, com os percentis 5, 50 e 95, respectivamente. O comprimento cervical uterino diminuiu progressivamente ao longo da gestação normal, sendo esse encurtamento significativo após a 20ª semana de gravidez e mais expressivo após a 28ª semana (pPURPOSE: to establish a normality curve of cervical length during pregnancy measured by transvaginal ultrasonography. METHODS: we conducted a prospective, longitudinal study on 82 healthy pregnant women who were followed up from the beginning of pregnancy to delivery at four-week intervals, of whom 49 concluded the study. Patients were divided according to parity into nulliparous women and women with one or more previous deliveries. Cervical length was measured in a sagittal view by transvaginal ultrasonography, as the linear distance between internal and external cervical os. RESULTS: no significant difference was observed in mean cervical length or the 5th, 25, 50th, 75th, or 95th percentile according to gestational age between groups (p>0

  5. Pion nucleus scattering lengths

    International Nuclear Information System (INIS)

    Huang, W.T.; Levinson, C.A.; Banerjee, M.K.

    1971-09-01

    Soft pion theory and the Fubini-Furlan mass dispersion relations have been used to analyze the pion nucleon scattering lengths and obtain a value for the sigma commutator term. With this value and using the same principles, scattering lengths have been predicted for nuclei with mass number ranging from 6 to 23. Agreement with experiment is very good. For those who believe in the Gell-Mann-Levy sigma model, the evaluation of the commutator yields the value 0.26(m/sub σ//m/sub π/) 2 for the sigma nucleon coupling constant. The large dispersive corrections for the isosymmetric case implies that the basic idea behind many of the soft pion calculations, namely, slow variation of matrix elements from the soft pion limit to the physical pion mass, is not correct. 11 refs., 1 fig., 3 tabs

  6. Sorghum cobalt analysis on not determined wave length with atomic ...

    African Journals Online (AJOL)

    This study was to know the better wave length on measuring cobalt content in forage sorghum hybrid (Sorghum bicolor) with an atomic absorption spectrophotometer. The analysis was on background correction mode with three wave lengths; 240.8, 240.7 (determined wave length or recommended wave length) and 240.6 ...

  7. Gap length distributions by PEPR

    International Nuclear Information System (INIS)

    Warszawer, T.N.

    1980-01-01

    Conditions guaranteeing exponential gap length distributions are formulated and discussed. Exponential gap length distributions of bubble chamber tracks first obtained on a CRT device are presented. Distributions of resulting average gap lengths and their velocity dependence are discussed. (orig.)

  8. Relativistic length agony continued

    Directory of Open Access Journals (Sweden)

    Redžić D.V.

    2014-01-01

    Full Text Available We made an attempt to remedy recent confusing treatments of some basic relativistic concepts and results. Following the argument presented in an earlier paper (Redžić 2008b, we discussed the misconceptions that are recurrent points in the literature devoted to teaching relativity such as: there is no change in the object in Special Relativity, illusory character of relativistic length contraction, stresses and strains induced by Lorentz contraction, and related issues. We gave several examples of the traps of everyday language that lurk in Special Relativity. To remove a possible conceptual and terminological muddle, we made a distinction between the relativistic length reduction and relativistic FitzGerald-Lorentz contraction, corresponding to a passive and an active aspect of length contraction, respectively; we pointed out that both aspects have fundamental dynamical contents. As an illustration of our considerations, we discussed briefly the Dewan-Beran-Bell spaceship paradox and the ‘pole in a barn’ paradox. [Projekat Ministarstva nauke Republike Srbije, br. 171028

  9. Absolute and relative-rate measurement of the rate coefficient for reaction of perfluoro ethyl vinyl ether (C2F5OCF[double bond, length as m-dash]CF2) with OH.

    Science.gov (United States)

    Srinivasulu, G; Bunkan, A J C; Amedro, D; Crowley, J N

    2018-01-31

    The rate coefficient (k 1 ) for the reaction of OH radicals with perfluoro ethyl vinyl ether (PEVE, C 2 F 5 OCF[double bond, length as m-dash]CF 2 ) has been measured as a function of temperature (T = 207-300 K) using the technique of pulsed laser photolysis with detection of OH by laser-induced fluorescence (PLP-LIF) at pressures of 50 or 100 Torr N 2 bath gas. In addition, the rate coefficient was measured at 298 K and in one atmosphere of air by the relative-rate technique with loss of PEVE and reference reactant monitored in situ by IR absorption spectroscopy. The rate coefficient has a negative temperature dependence which can be parameterized as: k 1 (T) = 6.0 × 10 -13  exp[(480 ± 38/T)] cm 3 molecule -1 s -1 and a room temperature value of k 1 (298 K) = (3.0 ± 0.3) × 10 -12 cm 3 molecule -1 s -1 . Highly accurate rate coefficients from the PLP-LIF experiments were achieved by optical on-line measurements of PEVE and by performing the measurements at two different apparatuses. The large rate coefficient and the temperature dependence indicate that the reaction proceeds via OH addition to the C[double bond, length as m-dash]C double bond, the high pressure limit already being reached at 50 Torr N 2 . Based on the rate coefficient and average OH levels, the atmospheric lifetime of PEVE was estimated to be a few days.

  10. Validity and repeatability of inertial measurement units for measuring gait parameters.

    Science.gov (United States)

    Washabaugh, Edward P; Kalyanaraman, Tarun; Adamczyk, Peter G; Claflin, Edward S; Krishnan, Chandramouli

    2017-06-01

    Inertial measurement units (IMUs) are small wearable sensors that have tremendous potential to be applied to clinical gait analysis. They allow objective evaluation of gait and movement disorders outside the clinic and research laboratory, and permit evaluation on large numbers of steps. However, repeatability and validity data of these systems are sparse for gait metrics. The purpose of this study was to determine the validity and between-day repeatability of spatiotemporal metrics (gait speed, stance percent, swing percent, gait cycle time, stride length, cadence, and step duration) as measured with the APDM Opal IMUs and Mobility Lab system. We collected data on 39 healthy subjects. Subjects were tested over two days while walking on a standard treadmill, split-belt treadmill, or overground, with IMUs placed in two locations: both feet and both ankles. The spatiotemporal measurements taken with the IMU system were validated against data from an instrumented treadmill, or using standard clinical procedures. Repeatability and minimally detectable change (MDC) of the system was calculated between days. IMUs displayed high to moderate validity when measuring most of the gait metrics tested. Additionally, these measurements appear to be repeatable when used on the treadmill and overground. The foot configuration of the IMUs appeared to better measure gait parameters; however, both the foot and ankle configurations demonstrated good repeatability. In conclusion, the IMU system in this study appears to be both accurate and repeatable for measuring spatiotemporal gait parameters in healthy young adults. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. The length of the male urethra

    Directory of Open Access Journals (Sweden)

    Tobias. S. Kohler

    2008-08-01

    Full Text Available PURPOSE: Catheter-based medical devices are an important component of the urologic armamentarium. To our knowledge, there is no population-based data regarding normal male urethral length. We evaluated the length of the urethra in men with normal genitourinary anatomy undergoing either Foley catheter removal or standard cystoscopy. MATERIALS AND METHODS: Male urethral length was obtained in 109 men. After study permission was obtained, the subject's penis was placed on a gentle stretch and the catheter was marked at the tip of the penis. The catheter was then removed and the distance from the mark to the beginning of the re-inflated balloon was measured. Alternatively, urethral length was measured at the time of cystoscopy, on removal of the cystoscope. Data on age, weight, and height was obtained in patients when possible. RESULTS: The mean urethral length was 22.3 cm with a standard deviation of 2.4 cm. Urethral length varied between 15 cm and 29 cm. No statistically significant correlation was found between urethral length and height, weight, body mass index (BMI, or age. CONCLUSIONS: Literature documenting the length of the normal male adult urethra is scarce. Our data adds to basic anatomic information of the male urethra and may be used to optimize genitourinary device design.

  12. The analysis of projected fission track lengths

    International Nuclear Information System (INIS)

    Laslett, G.M.; Galbraith, R.F.; Green, P.F.

    1994-01-01

    This article deals with the question of how features of the thermal history can be estimated from projected track length measurements, i.e. lengths of the remaining parts of tracks that have intersected a surface, projected onto that surface. The appropriate mathematical theory is described and used to provide a sound basis both for understanding the nature of projected length measurements and for analysing observed data. The estimation of thermal history parameters corresponding to the current temperature, the maximum palaeotemperature and the time since cooling, is studied using laboratory data and simulations. In general the information contained in projected track lengths and angles is fairly limited, compared, for example, with that from a much smaller number of confined tracks, though we identify some circumstances when such measurements may be useful. Also it is not straightforward to extract the information and simple ad hoc estimation methods are generally inadequate. (author)

  13. Intersubunit distances in full-length, dimeric, bacterial phytochrome Agp1, as measured by pulsed electron-electron double resonance (PELDOR) between different spin label positions, remain unchanged upon photoconversion.

    Science.gov (United States)

    Kacprzak, Sylwia; Njimona, Ibrahim; Renz, Anja; Feng, Juan; Reijerse, Edward; Lubitz, Wolfgang; Krauss, Norbert; Scheerer, Patrick; Nagano, Soshichiro; Lamparter, Tilman; Weber, Stefan

    2017-05-05

    Bacterial phytochromes are dimeric light-regulated histidine kinases that convert red light into signaling events. Light absorption by the N-terminal photosensory core module (PCM) causes the proteins to switch between two spectrally distinct forms, Pr and Pfr, thus resulting in a conformational change that modulates the C-terminal histidine kinase region. To provide further insights into structural details of photoactivation, we investigated the full-length Agp1 bacteriophytochrome from the soil bacterium Agrobacterium fabrum using a combined spectroscopic and modeling approach. We generated seven mutants suitable for spin labeling to enable application of pulsed EPR techniques. The distances between attached spin labels were measured using pulsed electron-electron double resonance spectroscopy to probe the arrangement of the subunits within the dimer. We found very good agreement of experimental and calculated distances for the histidine-kinase region when both subunits are in a parallel orientation. However, experimental distance distributions surprisingly showed only limited agreement with either parallel- or antiparallel-arranged dimer structures when spin labels were placed into the PCM region. This observation indicates that the arrangements of the PCM subunits in the full-length protein dimer in solution differ significantly from that in the PCM crystals. The pulsed electron-electron double resonance data presented here revealed either no or only minor changes of distance distributions upon Pr-to-Pfr photoconversion. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  14. Economic issues of broiler production length

    Directory of Open Access Journals (Sweden)

    Szőllősi László

    2014-01-01

    Full Text Available The length of broiler production cycle is also an important factor when profitability is measured. This paper is to determine the effects of different market ages and down-time period, overall broiler production cycle length on performance and economic parameters based on Hungarian production and financial circumstances. A deterministic model was constructed to manage the function-like correlations of age-related daily weight gain, daily feed intake and daily mortality data. The results show that broiler production cycle length has a significant effect on production and economic performance. Cycle length is determined by the length of down-time and grow-out periods. If down-time period is reduced by one day, an average net income of EUR 0.55 per m2 is realizable. However, the production period is not directly proportional either with emerging costs or obtainable revenues. Profit maximization is attainable if the production period is 41-42 days.

  15. Microcomputer system for controlling fuel rod length

    International Nuclear Information System (INIS)

    Meyer, E.R.; Bouldin, D.W.; Bolfing, B.J.

    1979-01-01

    A system is being developed at the Oak Ridge National Laboratory (ORNL) to automatically measure and control the length of fuel rods for use in a high temperature gas-cooled reactor (HTGR). The system utilizes an LSI-11 microcomputer for monitoring fuel rod length and for adjusting the primary factor affecting length. Preliminary results indicate that the automated system can maintain fuel rod length within the specified limits of 1.940 +- 0.040 in. This system provides quality control documentation and eliminates the dependence of the current fuel rod molding process on manual length control. In addition, the microcomputer system is compatible with planned efforts to extend control to fuel rod fissile and fertile material contents

  16. Penile length and circumference: an Indian study.

    Science.gov (United States)

    Promodu, K; Shanmughadas, K V; Bhat, S; Nair, K R

    2007-01-01

    Apprehension about the normal size of penis is a major concern for men. Aim of the present investigation is to estimate the penile length and circumference of Indian males and to compare the results with the data from other countries. Results will help in counseling the patients worried about the penile size and seeking penis enlargement surgery. Penile length in flaccid and stretched conditions and circumference were measured in a group of 301 physically normal men. Erected length and circumference were measured for 93 subjects. Mean flaccid length was found to be 8.21 cm, mean stretched length 10.88 cm and circumference 9.14 cm. Mean erected length was found to be 13.01 cm and erected circumference was 11.46 cm. Penile dimensions are found to be correlated with anthropometric parameters. Insight into the normative data of penile size of Indian males obtained. There are significant differences in the mean penile length and circumference of Indian sample compared to the data reported from other countries. Study need to be continued with a large sample to establish a normative data applicable to the general population.

  17. AGS vertical beta function measurements for Run 15

    Energy Technology Data Exchange (ETDEWEB)

    Harper, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ahrens, L. [Brookhaven National Lab. (BNL), Upton, NY (United States); Huang, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Schoefer, V. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-10-07

    One key parameter for running the AGS efficiently is by maintaining a low emittance. To measure emittance, one needs to measure the beta function throughout the cycle. This can be done by measuring the beta function at the ionization profile monitors (IPM) in the AGS. This tech note delves into the motivation, the measurement, and some strides that were made throughout Run15.

  18. Automatic Control Of Length Of Welding Arc

    Science.gov (United States)

    Iceland, William F.

    1991-01-01

    Nonlinear relationships among current, voltage, and length stored in electronic memory. Conceptual microprocessor-based control subsystem maintains constant length of welding arc in gas/tungsten arc-welding system, even when welding current varied. Uses feedback of current and voltage from welding arc. Directs motor to set position of torch according to previously measured relationships among current, voltage, and length of arc. Signal paths marked "calibration" or "welding" used during those processes only. Other signal paths used during both processes. Control subsystem added to existing manual or automatic welding system equipped with automatic voltage control.

  19. Kidney Length in Normal Korean Children

    International Nuclear Information System (INIS)

    Kim, In One; Cheon, Jung Eun; Lee, Young Seok; Lee, Sun Wha; Kim, Ok Hwa; Kim, Ji Hye; Kim, Hong Dae; Sim, Jung Suk

    2010-01-01

    Renal length offers important information to detect or follow-up various renal diseases. The purpose of this study was to determine the kidney length of normal Korean children in relation to age, height, weight, body surface area (BSA), and body mass index (BMI). Children between 1 month and 15 years of age without urological abnormality were recruited. Children below 3rd percentile and over 97th percentile for height or weight were excluded. Both renal lengths were measured in the prone position three times and then averaged by experienced radiologists. The mean length and standard deviation for each age group was obtained, and regression equation was calculated between renal length and age, weight, height, BSA, and BMI, respectively. Renal length was measured in 550 children. Renal length grows rapidly until 24 month, while the growth rate is reduced thereafter. The regression equation for age is: renal length (mm) = 45.953 + 1.064 x age (month, ≤ 24 months) (R2 = 0.720) or 62.173 + 0.203 x age (months, > 24 months) (R2 = 0.711). The regression equation for height is: renal length (mm) = 24.494 + 0.457 x height (cm) (R2 = 0.894). The regression equation for weight is: renal length (mm) = 38.342 + 2.117 x weight (kg, ≤18 kg) (R2 = 0.852) or 64.498 + 0.646 x weight (kg, > 18 kg) (R2 = 0.651). The regression equation for BSA is: renal length (mm) = 31.622 + 61.363 x BSA (m2, ≤ 0.7) (R2 = 0.857) or 52.717 + 29.959 x BSA (m2, > 0.7) (R2 = 0.715). The regression equation for BMI is: renal length (mm) = 44.474 + 1.163 x BMI (R2 = 0.079). This study provides data on the normal renal length and its association with age, weight, height, BSA and BMI. The results of this study will guide the detection and follow-up of renal diseases in Korean children

  20. Menstrual cycle length: a surrogate measure of reproductive health capable of improving the accuracy of biochemical/sonographical ovarian reserve test in estimating the reproductive chances of women referred to ART.

    Science.gov (United States)

    Gizzo, Salvatore; Andrisani, Alessandra; Noventa, Marco; Quaranta, Michela; Esposito, Federica; Armanini, Decio; Gangemi, Michele; Nardelli, Giovanni B; Litta, Pietro; D'Antona, Donato; Ambrosini, Guido

    2015-04-10

    Aim of the study was to investigate whether menstrual cycle length may be considered as a surrogate measure of reproductive health, improving the accuracy of biochemical/sonographical ovarian reserve test in estimating the reproductive chances of women referred to ART. A retrospective-observational-study in Padua' public tertiary level Centre was conducted. A total of 455 normo-ovulatory infertile women scheduled for their first fresh non-donor IVF/ICSI treatment. The mean menstrual cycle length (MCL) during the preceding 6 months was calculated by physicians on the basis of information contained in our electronic database (first day of menstrual cycle collected every month by telephonic communication by single patients). We evaluated the relations between MCL, ovarian response to stimulation protocol, oocytes fertilization ratio, ovarian sensitivity index (OSI) and pregnancy rate in different cohorts of patients according to the class of age and the estimated ovarian reserve. In women younger than 35 years, MCL over 31 days may be associated with an increased risk of OHSS and with a good OSI. In women older than 35 years, and particularly than 40 years, MCL shortening may be considered as a marker of ovarian aging and may be associated with poor ovarian response, low OSI and reduced fertilization rate. When AMH serum value is lower than 1.1 ng/ml in patients older than 40 years, MCL may help Clinicians discriminate real from expected poor responders. Considering the pool of normoresponders, MCL was not correlated with pregnancy rate while a positive association was found with patients' age. MCL diary is more predictive than chronological age in estimating ovarian biological age and response to COH and it is more predictive than AMH in discriminating expected from real poor responders. In women older than 35 years MCL shortening may be considered as a marker of ovarian aging while chronological age remains most accurate parameter in predicting pregnancy.

  1. Método para medida do comprimento da cóclea por meio de ressonância magnética A method for measuring the length of the coclea through magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Fernando Pochini Sobrinho

    2009-04-01

    Full Text Available Sabe-se que a deficiência auditiva afeta boa parte da população. Nos casos em que a surdez é profunda e bilateral, podem ocorrer problemas na aquisição de fala nas crianças, bem como na comunicação e socialização do indivíduo. O implante coclear vem sendo utilizado como opção terapêutica para esses casos. Na atualidade a Ressonância magnética da orelha interna é exame obrigatório na avaliação pré-operatória destes pacientes. No dia-a-dia, nos perguntamos se a ressonância magnética pode fornecer dados não só qualitativos como também quantitativos, com medidas lineares reais na cóclea reconstruída em imagens em três dimensões. OBJETIVO: O objetivo deste estudo é propor uma técnica para obtenção de medidas do comprimento da cóclea em imagens de ressonância magnética obtidos de ossos temporais de cadáveres. MATERIAL E MÉTODO: Foram avaliadas imagens de reconstrução em três dimensões da cóclea de seis cadáveres. Por meio de sobreposição de réguas digitalizadas sobre estas imagens foi possível medir o comprimento coclear. RESULTADO: Estas medidas variaram de 17 a 26,5 milímetros. CONCLUSÃO: Conclui-se que foi possível medir o comprimento da cóclea em imagens em três dimensões de ressonância magnética pelo método proposto.We know that hearing impairment affects a large part of the population. In cases of profound and bilateral hearing loss, children may have problems in speech development, as well as communication and socialization. Cochlear implants have been used as a treatment option in these cases. Today, inner ear MRI is a mandatory test in the preoperative evaluation of these individuals. In our daily routines, we wonder whether MRI can provide not only qualitative, but also quantitative data, with real cochlear linear values built from three dimension images. AIMS: The aim of the present investigation is to propose a method to obtain MRI cochlear length measures from the temporal bones

  2. The comparison between the length of vertical dimension of occlusion and the length of thumb on undergraduate Mongoloid students

    Directory of Open Access Journals (Sweden)

    Goh Li Teng

    2011-03-01

    Full Text Available The Thumb Rule of Leonardo da Vinci states that many proportions of the face show relationship with the length of thumb which is measured from the proximal tip of the proximal phalanx to the distal tip of the distal phalanx. Previous studies have shown that the length of the vertical dimension of occlusion (VDO is similar to the length of thumb of the Caucasoid race. The purpose of this study is to determine whether the length of VDO have correlations with the length of thumb among those of the Mongoloid race. This study took a survey method with the analytical cross-sectional approach. A total of 80 students of Faculty of Dentistry who have fulfilled all population criteria were randomly chosen to measure the length of VDO and the length of the thumb. Results analyzed with Student's t-test statistic revealed that there was a significant difference between males and females in the length of VDO and the length of the thumb, however, there was no significant difference between the length of VDO and the length of the thumb. There were very strong correlations (P<0.05 between the length of VDO and the length of the thumb. As a conclusion, the length of thumb can be suggested as an objective method to determine the length of VDO in this population.

  3. Full Length Research Article

    African Journals Online (AJOL)

    Dr Ahmed

    The isotope techniques used in hydrology may be classified into three groups: environmental ..... In that case a solution may be found in measurements of 14C content of groundwaters. ... Applied Isotope Hydrogeology. Elsevier, New. York.

  4. Influenza activity in Europe during eight seasons (1999–2007: an evaluation of the indicators used to measure activity and an assessment of the timing, length and course of peak activity (spread across Europe

    Directory of Open Access Journals (Sweden)

    Meijer Adam

    2007-11-01

    Full Text Available Abstract Background The European Influenza Surveillance Scheme (EISS has collected clinical and virological data on influenza since 1996 in an increasing number of countries. The EISS dataset was used to characterise important epidemiological features of influenza activity in Europe during eight winters (1999–2007. The following questions were addressed: 1 are the sentinel clinical reports a good measure of influenza activity? 2 how long is a typical influenza season in Europe? 3 is there a west-east and/or south-north course of peak activity ('spread' of influenza in Europe? Methods Influenza activity was measured by collecting data from sentinel general practitioners (GPs and reports by national reference laboratories. The sentinel reports were first evaluated by comparing them to the laboratory reports and were then used to assess the timing and spread of influenza activity across Europe during eight seasons. Results We found a good match between the clinical sentinel data and laboratory reports of influenza collected by sentinel physicians (overall match of 72% for +/- 1 week difference. We also found a moderate to good match between the clinical sentinel data and laboratory reports of influenza from non-sentinel sources (overall match of 60% for +/- 1 week. There were no statistically significant differences between countries using ILI (influenza-like illness or ARI (acute respiratory disease as case definition. When looking at the peak-weeks of clinical activity, the average length of an influenza season in Europe was 15.6 weeks (median 15 weeks; range 12–19 weeks. Plotting the peak weeks of clinical influenza activity reported by sentinel GPs against the longitude or latitude of each country indicated that there was a west-east spread of peak activity (spread of influenza across Europe in four winters (2001–2002, 2002–2003, 2003–2004 and 2004–2005 and a south-north spread in three winters (2001–2002, 2004–2005 and 2006

  5. Combining Single-Molecule Optical Trapping and Small-Angle X-Ray Scattering Measurements to Compute the Persistence Length of a Protein ER/K alpha-Helix

    DEFF Research Database (Denmark)

    Sivaramakrishnan, S.; Sung, J.; Ali, M.

    2009-01-01

    as a force transducer, rigid spacer, or flexible linker in proteins. In this study, we quantity this flexibility in terms of persistence length, namely the length scale over which it is rigid. We use single-molecule optical trapping and small-angle x-ray scattering, combined with Monte Carlo simulations...

  6. LENGTH-WEIGHT RELATIONSHIP AND CONDITION FACTOR OF ...

    African Journals Online (AJOL)

    Data Collection and Analysis. The measurements of length (cm), weight (g) and the condition factor of individual fish sampled were recorded. The relationship between length and weight of the fish was examined by simple linear regression using WINKS software. The variations in the length-weight represented by 'b' were.

  7. Controlling the optical path length in turbid media using differential path-length spectroscopy: fiber diameter dependence

    NARCIS (Netherlands)

    Kaspers, O. P.; Sterenborg, H. J. C. M.; Amelink, A.

    2008-01-01

    We have characterized the path length for the differential path-length spectroscopy (DPS) fiber optic geometry for a wide range of optical properties and for fiber diameters ranging from 200 mu m to 1000 mu m. Phantom measurements show that the path length is nearly constant for scattering

  8. Length expectation values in quantum Regge calculus

    International Nuclear Information System (INIS)

    Khatsymovsky, V.M.

    2004-01-01

    Regge calculus configuration superspace can be embedded into a more general superspace where the length of any edge is defined ambiguously depending on the 4-tetrahedron containing the edge. Moreover, the latter superspace can be extended further so that even edge lengths in each the 4-tetrahedron are not defined, only area tensors of the 2-faces in it are. We make use of our previous result concerning quantization of the area tensor Regge calculus which gives finite expectation values for areas. Also our result is used showing that quantum measure in the Regge calculus can be uniquely fixed once we know quantum measure on (the space of the functionals on) the superspace of the theory with ambiguously defined edge lengths. We find that in this framework quantization of the usual Regge calculus is defined up to a parameter. The theory may possess nonzero (of the order of Planck scale) or zero length expectation values depending on whether this parameter is larger or smaller than a certain value. Vanishing length expectation values means that the theory is becoming continuous, here dynamically in the originally discrete framework

  9. Neutron scattering lengths of 3He

    International Nuclear Information System (INIS)

    Alfimenkov, V.P.; Akopian, G.G.; Wierzbicki, J.; Govorov, A.M.; Pikelner, L.B.; Sharapov, E.I.

    1976-01-01

    The total neutron scattering cross-section of 3 He has been measured in the neutron energy range from 20 meV to 2 eV. Together with the known value of coherent scattering amplitude it leads to the two sts of n 3 He scattering lengths

  10. Ultrasonographic assessment of renal length in 310 Turkish children ...

    African Journals Online (AJOL)

    Scanning was performed with a 3.5 MHz ultrasound probe in the supine position. The ultrasonographic appearance of the kidneys we measured was normal. The maximum length of each kidney was measured. The renal length was correlated with somatic parameters including age, body height and weight. Regression ...

  11. Generation of Length Distribution, Length Diagram, Fibrogram, and Statistical Characteristics by Weight of Cotton Blends

    Directory of Open Access Journals (Sweden)

    B. Azzouz

    2007-01-01

    Full Text Available The textile fibre mixture as a multicomponent blend of variable fibres imposes regarding the proper method to predict the characteristics of the final blend. The length diagram and the fibrogram of cotton are generated. Then the length distribution, the length diagram, and the fibrogram of a blend of different categories of cotton are determined. The length distributions by weight of five different categories of cotton (Egyptian, USA (Pima, Brazilian, USA (Upland, and Uzbekistani are measured by AFIS. From these distributions, the length distribution, the length diagram, and the fibrogram by weight of four binary blends are expressed. The length parameters of these cotton blends are calculated and their variations are plotted against the mass fraction x of one component in the blend .These calculated parameters are compared to those of real blends. Finally, the selection of the optimal blends using the linear programming method, based on the hypothesis that the cotton blend parameters vary linearly in function of the components rations, is proved insufficient.

  12. Randomized Controlled Trial Comparing Exercise to Health Education for Stimulant Use Disorder: Results From the CTN-0037 STimulant Reduction Intervention Using Dosed Exercise (STRIDE) Study.

    Science.gov (United States)

    Trivedi, Madhukar H; Greer, Tracy L; Rethorst, Chad D; Carmody, Thomas; Grannemann, Bruce D; Walker, Robrina; Warden, Diane; Shores-Wilson, Kathy; Stoutenberg, Mark; Oden, Neal; Silverstein, Meredith; Hodgkins, Candace; Love, Lee; Seamans, Cindy; Stotts, Angela; Causey, Trey; Szucs-Reed, Regina P; Rinaldi, Paul; Myrick, Hugh; Straus, Michele; Liu, David; Lindblad, Robert; Church, Timothy; Blair, Steven N; Nunes, Edward V

    To evaluate exercise as a treatment for stimulant use disorders. The STimulant Reduction Intervention using Dosed Exercise (STRIDE) study was a randomized clinical trial conducted in 9 residential addiction treatment programs across the United States from July 2010 to February 2013. Of 497 adults referred to the study, 302 met all eligibility criteria, including DSM-IV criteria for stimulant abuse and/or dependence, and were randomized to either a dosed exercise intervention (Exercise) or a health education intervention (Health Education) control, both augmenting treatment as usual and conducted thrice weekly for 12 weeks. The primary outcome of percent stimulant abstinent days during study weeks 4 to 12 was estimated using a novel algorithm adjustment incorporating self-reported Timeline Followback (TLFB) stimulant use and urine drug screen (UDS) data. Mean percent of abstinent days based on TLFB was 90.8% (SD = 16.4%) for Exercise and 91.6% (SD = 14.7%) for Health Education participants. Percent of abstinent days using the eliminate contradiction (ELCON) algorithm was 75.6% (SD = 27.4%) for Exercise and 77.3% (SD = 25.1%) for Health Education. The primary intent-to-treat analysis, using a mixed model controlling for site and the ELCON algorithm, produced no treatment effect (P = .60). In post hoc analyses controlling for treatment adherence and baseline stimulant use, Exercise participants had a 4.8% higher abstinence rate (78.7%) compared to Health Education participants (73.9%) (P = .03, number needed to treat = 7.2). The primary analysis indicated no significant difference between exercise and health education. Adjustment for intervention adherence showed modestly but significantly higher percent of abstinent days in the exercise group, suggesting that exercise may improve outcomes for stimulant users who have better adherence to an exercise dose. ClinicalTrials.gov identifier: NCT01141608. © Copyright 2017 Physicians Postgraduate Press, Inc.

  13. Discrepancies in reporting the CAG repeat lengths for Huntington's disease

    DEFF Research Database (Denmark)

    Quarrell, Oliver W; Handley, Olivia; O'Donovan, Kirsty

    2011-01-01

    Huntington's disease results from a CAG repeat expansion within the Huntingtin gene; this is measured routinely in diagnostic laboratories. The European Huntington's Disease Network REGISTRY project centrally measures CAG repeat lengths on fresh samples; these were compared with the original...

  14. Information-theoretic lengths of Jacobi polynomials

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero, A; Dehesa, J S [Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Granada, Granada (Spain); Sanchez-Moreno, P, E-mail: agmartinez@ugr.e, E-mail: pablos@ugr.e, E-mail: dehesa@ugr.e [Instituto ' Carlos I' de Fisica Teorica y Computacional, Universidad de Granada, Granada (Spain)

    2010-07-30

    The information-theoretic lengths of the Jacobi polynomials P{sup ({alpha}, {beta})}{sub n}(x), which are information-theoretic measures (Renyi, Shannon and Fisher) of their associated Rakhmanov probability density, are investigated. They quantify the spreading of the polynomials along the orthogonality interval [- 1, 1] in a complementary but different way as the root-mean-square or standard deviation because, contrary to this measure, they do not refer to any specific point of the interval. The explicit expressions of the Fisher length are given. The Renyi lengths are found by the use of the combinatorial multivariable Bell polynomials in terms of the polynomial degree n and the parameters ({alpha}, {beta}). The Shannon length, which cannot be exactly calculated because of its logarithmic functional form, is bounded from below by using sharp upper bounds to general densities on [- 1, +1] given in terms of various expectation values; moreover, its asymptotics is also pointed out. Finally, several computational issues relative to these three quantities are carefully analyzed.

  15. Crack Length Detection by Digital Image Processing

    DEFF Research Database (Denmark)

    Lyngbye, Janus; Brincker, Rune

    1990-01-01

    It is described how digital image processing is used for measuring the length of fatigue cracks. The system is installed in a Personal Computer equipped with image processing hardware and performs automated measuring on plane metal specimens used in fatigue testing. Normally one can not achieve...... a resolution better then that of the image processing equipment. To overcome this problem an extrapolation technique is used resulting in a better resolution. The system was tested on a specimen loaded with different loads. The error σa was less than 0.031 mm, which is of the same size as human measuring...

  16. Correlations between the cross-sectional area and moment arm length of the erector spinae muscle and the thickness of the psoas major muscle as measured by MRI and the body mass index in lumbar degenerative kyphosis patients

    International Nuclear Information System (INIS)

    Lee, Hyun; Lee, Sang Jin; Lee, Sang Ho

    2006-01-01

    Lumbar degenerative kyphosis (LDK) is a subgroup of the flatback syndrome, which is a condition caused by spinal degeneration. LDK is reported to be the most frequent cause of lumbar spine deformity in the farming districts of the 'oriental' countries. We investigated the relationship between the cross-sectional area (CSA) and the moment arm length (MAL) of the erector spinae muscle and the thickness of the psoas major muscle (PT) and the body mass index (BMI) by performing statistical analysis, and we tried to show the crucial role of these variables for diagnosing LDK. From July 2004 to April 2005, we retrospectively reviewed 17 LDK patients who had undergone anterior lumbar interbody fusion (ALIF) with posterior stabilization. We measured both the CSA and MAL on the transverse cross-sectional MR image of the trunk at the fourth to fifth vertebrae (L4/5). The MAL was defined as the anterior-posterior distance between the center of the erector spinae muscle and that of the vertebral body. A comparative study was undertaken between the LDK group and the matched (according to age and gender) control group with regard to the CSA, MAL, PT and BMI. The 17 LDK patients were all females [age: 62.5 ± 4.93 years, height: 157 ± 6.19 cm, weight: 55.59 ± 4.7 kg, and BMI: 22.58 ± 2.08 kg/m 2 ]. The control group patients were all female [age: 63.6 ± 2.27 years, height: 156 ± 5.05 cm, weight: 59.65 ± 7.39 kg and BMI: 24.38 ± 2.94 kg/m 2 ]. Spearman's rho indicated a positive association between the CSA and BMI (rho = 0.49, ρ = 0.046), between the MAL and BMI (rho = 0.808, ρ = 0.000) and between the CSA and PT (rho = 0.566, ρ = 0.018) in the LDK patients. In terms of the CSA versus MAL, there was a positive association in both groups (rho = 0.67, ρ = 0.000, MAL = 0.023CSA + 5.454 in the LDK group; rho = 0.564, ρ 0.018, MAL = 0.02CSA + 5.832 in the control group with using linear regression analysis). Independent t-tests revealed that both groups had statistically

  17. A 13 kA current lead, measuring 1.5 m in length. The lower part consists of a high-temperature superconductor (Bi-2223), operating at between 50 K and 4.5 K, while the heat-exchanger upper part allows the current to be brought from room temperature to 50 K.

    CERN Multimedia

    2004-01-01

    A 13 kA current lead, measuring 1.5 m in length. The lower part consists of a high-temperature superconductor (Bi-2223), operating at between 50 K and 4.5 K, while the heat-exchanger upper part allows the current to be brought from room temperature to 50 K.

  18. Summary of coherent neutron scattering length

    International Nuclear Information System (INIS)

    Rauch, H.

    1981-07-01

    Experimental values of neutron-nuclei bound scattering lengths for some 354 isotopes and elements and the various spin-states are compiled in a uniform way together with their error bars as quoted in the original literature. Recommended values are also given. The definitions of the relevant quantities presented in the data tables and the basic principles of measurements are explained in the introductory chapters. The data is also available on a magnetic tape

  19. Does length or neighborhood size cause the word length effect?

    Science.gov (United States)

    Jalbert, Annie; Neath, Ian; Surprenant, Aimée M

    2011-10-01

    Jalbert, Neath, Bireta, and Surprenant (2011) suggested that past demonstrations of the word length effect, the finding that words with fewer syllables are recalled better than words with more syllables, included a confound: The short words had more orthographic neighbors than the long words. The experiments reported here test two predictions that would follow if neighborhood size is a more important factor than word length. In Experiment 1, we found that concurrent articulation removed the effect of neighborhood size, just as it removes the effect of word length. Experiment 2 demonstrated that this pattern is also found with nonwords. For Experiment 3, we factorially manipulated length and neighborhood size, and found only effects of the latter. These results are problematic for any theory of memory that includes decay offset by rehearsal, but they are consistent with accounts that include a redintegrative stage that is susceptible to disruption by noise. The results also confirm the importance of lexical and linguistic factors on memory tasks thought to tap short-term memory.

  20. Keeping disease at arm's length

    DEFF Research Database (Denmark)

    Lassen, Aske Juul

    2015-01-01

    active ageing change everyday life with chronic disease, and how do older people combine an active life with a range of chronic diseases? The participants in the study use activities to keep their diseases at arm’s length, and this distancing of disease at the same time enables them to engage in social...... and physical activities at the activity centre. In this way, keeping disease at arm’s length is analysed as an ambiguous health strategy. The article shows the importance of looking into how active ageing is practised, as active ageing seems to work well in the everyday life of the older people by not giving...... emphasis to disease. The article is based on ethnographic fieldwork and uses vignettes of four participants to show how they each keep diseases at arm’s length....

  1. Continuously variable focal length lens

    Science.gov (United States)

    Adams, Bernhard W; Chollet, Matthieu C

    2013-12-17

    A material preferably in crystal form having a low atomic number such as beryllium (Z=4) provides for the focusing of x-rays in a continuously variable manner. The material is provided with plural spaced curvilinear, optically matched slots and/or recesses through which an x-ray beam is directed. The focal length of the material may be decreased or increased by increasing or decreasing, respectively, the number of slots (or recesses) through which the x-ray beam is directed, while fine tuning of the focal length is accomplished by rotation of the material so as to change the path length of the x-ray beam through the aligned cylindrical slows. X-ray analysis of a fixed point in a solid material may be performed by scanning the energy of the x-ray beam while rotating the material to maintain the beam's focal point at a fixed point in the specimen undergoing analysis.

  2. Kondo length in bosonic lattices

    Science.gov (United States)

    Giuliano, Domenico; Sodano, Pasquale; Trombettoni, Andrea

    2017-09-01

    Motivated by the fact that the low-energy properties of the Kondo model can be effectively simulated in spin chains, we study the realization of the effect with bond impurities in ultracold bosonic lattices at half filling. After presenting a discussion of the effective theory and of the mapping of the bosonic chain onto a lattice spin Hamiltonian, we provide estimates for the Kondo length as a function of the parameters of the bosonic model. We point out that the Kondo length can be extracted from the integrated real-space correlation functions, which are experimentally accessible quantities in experiments with cold atoms.

  3. Continuous lengths of oxide superconductors

    Science.gov (United States)

    Kroeger, Donald M.; List, III, Frederick A.

    2000-01-01

    A layered oxide superconductor prepared by depositing a superconductor precursor powder on a continuous length of a first substrate ribbon. A continuous length of a second substrate ribbon is overlaid on the first substrate ribbon. Sufficient pressure is applied to form a bound layered superconductor precursor powder between the first substrate ribbon and the second substrate ribbon. The layered superconductor precursor is then heat treated to establish the oxide superconducting phase. The layered oxide superconductor has a smooth interface between the substrate and the oxide superconductor.

  4. Summary of neutron scattering lengths

    International Nuclear Information System (INIS)

    Koester, L.

    1981-12-01

    All available neutron-nuclei scattering lengths are collected together with their error bars in a uniform way. Bound scattering lengths are given for the elements, the isotopes, and the various spin-states. They are discussed in the sense of their use as basic parameters for many investigations in the field of nuclear and solid state physics. The data bank is available on magnetic tape, too. Recommended values and a map of these data serve for an uncomplicated use of these quantities. (orig.)

  5. The length-weight and length-length relationships of bluefish, Pomatomus saltatrix (Linnaeus, 1766 from Samsun, middle Black Sea region

    Directory of Open Access Journals (Sweden)

    Melek Özpiçak

    2017-10-01

    Full Text Available In this study, length-weight relationship (LWR and length-length relationship (LLR of bluefish, Pomatomus saltatrix were determined. A total of 125 specimens were sampled from Samsun, the middle Black Sea in 2014 fishing season. Bluefish specimens were monthly collected from commercial fishing boats from October to December 2014. All captured individuals (N=125 were measured to the nearest 0.1 cm for total, fork and standard lengths. The weight of each fish (W was recorded to the nearest 0.01 g. According to results of analyses, there were no statistically significant differences between sexes in term of length and weight (P˃0.05. The minimum and maximum total, fork and standard lengths of bluefish ranged between 13.5-23.6 cm, 12.50-21.80 cm and 10.60-20.10 cm, respectively. The equation of length-weight relationship were calculated as W=0.008TL3.12 (r2>0.962. Positive allometric growth was observed for bluefish (b>3. Length-length relationship was also highly significant (P<0.001 with coefficient of determination (r2 ranging from 0.916 to 0.988.

  6. Diet, nutrition and telomere length.

    Science.gov (United States)

    Paul, Ligi

    2011-10-01

    The ends of human chromosomes are protected by DNA-protein complexes termed telomeres, which prevent the chromosomes from fusing with each other and from being recognized as a double-strand break by DNA repair proteins. Due to the incomplete replication of linear chromosomes by DNA polymerase, telomeric DNA shortens with repeated cell divisions until the telomeres reach a critical length, at which point the cells enter senescence. Telomere length is an indicator of biological aging, and dysfunction of telomeres is linked to age-related pathologies like cardiovascular disease, Parkinson disease, Alzheimer disease and cancer. Telomere length has been shown to be positively associated with nutritional status in human and animal studies. Various nutrients influence telomere length potentially through mechanisms that reflect their role in cellular functions including inflammation, oxidative stress, DNA integrity, DNA methylation and activity of telomerase, the enzyme that adds the telomeric repeats to the ends of the newly synthesized DNA. Copyright © 2011 Elsevier Inc. All rights reserved.

  7. Tube Length and Water Flow

    Directory of Open Access Journals (Sweden)

    Ben Ruktantichoke

    2011-06-01

    Full Text Available In this study water flowed through a straight horizontal plastic tube placed at the bottom of a large tank of water. The effect of changing the length of tubing on the velocity of flow was investigated. It was found that the Hagen-Poiseuille Equation is valid when the effect of water entering the tube is accounted for.

  8. Finite length Taylor Couette flow

    Science.gov (United States)

    Streett, C. L.; Hussaini, M. Y.

    1987-01-01

    Axisymmetric numerical solutions of the unsteady Navier-Stokes equations for flow between concentric rotating cylinders of finite length are obtained by a spectral collocation method. These representative results pertain to two-cell/one-cell exchange process, and are compared with recent experiments.

  9. Spatial correlation length of normalized cone data in sand

    DEFF Research Database (Denmark)

    Firouzianbandpey, Sarah; Griffiths, D. V.; Ibsen, Lars Bo

    2014-01-01

    The main topic of this study is to assess the anisotropic spatial correlation lengths of a sand layer deposit based on cone penetration testing with pore pressure measurement (CPTu) data. Spatial correlation length can be an important factor in reliability analysis of geotechnical systems, yet it...

  10. EFFECT OF EXERCISE ON CYCLE LENGTH IN ATRIAL-FLUTTER

    NARCIS (Netherlands)

    VANDENBERG, MP; CRIJNS, HJGM; SZABO, BM; BROUWER, J; LIE, KI

    Objective-To examine the effect of exercise on cycle length in atrial flutter. Patients-15 patients with chronic atrial flutter. Seven patients were taking digoxin and six verapamil; two were not taking medication. Methods-All patients underwent bicycle ergometry. Flutter cycle length was measured

  11. Length-weight relationship and condition factor of clarias gariepinus ...

    African Journals Online (AJOL)

    Length-Weight relationship and condition factor of Clarias gariepinus and Tilapia Zillii were studiedin lake Alau and Monguno hatchery, both in Borno State of Nigeria, for a period of two weeks. A total of 98 C. gariepinus and 140. T. zillii were measured. The length-weight regression coefficient (b) for both fishes in lake Alau ...

  12. Prediction of the mixing length in effluent transport in rivers

    International Nuclear Information System (INIS)

    Szpilowski, S.

    1983-01-01

    Studies have been performed on estimating the transverse mixing length of effluents discharged into rivers. The proposed method is based on measured values of the dispersion coefficient. Field investigations were carried out in the River Vistula in the Warsaw area using radiotracer methods. The procedure can be used for predicting the mixing length in designing sewage systems. (author)

  13. Local-field refinement of neutron scattering lengths

    Energy Technology Data Exchange (ETDEWEB)

    Sears, V F

    1985-06-01

    We examine the way in which local field effects in the neutron refractive index affect the values of coherent scattering lengths determined by various kinds of neutron optical measurements. We find that under typical experimental conditions these effects are negligible for interferometry measurements but that they are significant for gravity refractometry measurements, producing changes in the effective scattering length of as much as two or three standard deviations in some cases. Refined values of the scattering length are obtained for the thirteen elements for which data are presently available. The special role of local field effects in neutron transmission is also discussed.

  14. Local-field refinement of neutron scattering lengths

    International Nuclear Information System (INIS)

    Sears, V.F.

    1985-01-01

    We examine the way in which local field effects in the neutron refractive index affect the values of coherent scattering lengths determined by various kinds of neutron optical measurements. We find that under typical experimental conditions these effects are negligible for interferometry measurements but that they are significant for gravity refractometry measurements, producing changes in the effective scattering length of as much as two or three standard deviations in some cases. Refined values of the scattering length are obtained for the thirteen elements for which data are presently available. The special role of local field effects in neutron transmission is also discussed. (orig.)

  15. Quantitative fluorescence spectroscopy in turbid media using fluorescence differential path length spectroscopy

    NARCIS (Netherlands)

    Amelink, Arjen; Kruijt, Bastiaan; Robinson, Dominic J.; Sterenborg, Henricus J. C. M.

    2008-01-01

    We have developed a new technique, fluorescence differential path length spectroscopy (FDPS), that enables the quantitative investigation of fluorophores in turbid media. FDPS measurements are made with the same probe geometry as differential path length spectroscopy (DPS) measurements. Phantom

  16. ESTIMATION OF STATURE BASED ON FOOT LENGTH

    Directory of Open Access Journals (Sweden)

    Vidyullatha Shetty

    2015-01-01

    Full Text Available BACKGROUND : Stature is the height of the person in the upright posture. It is an important measure of physical identity. Estimation of body height from its segments or dismember parts has important considerations for identifications of living or dead human body or remains recovered from disasters or other similar conditions. OBJECTIVE : Stature is an important indicator for identification. There are numerous means to establish stature and their significance lies in the simplicity of measurement, applicability and accuracy in prediction. Our aim of the study was to review the relationship between foot length and body height. METHODS : The present study reviews various prospective studies which were done to estimate the stature. All the measurements were taken by using standard measuring devices and standard anthropometric techniques. RESULTS : This review shows there is a correlation between stature and foot dimensions it is found to be positive and statistically highly significant. Prediction of stature was found to be most accurate by multiple regression analysis. CONCLUSIONS : Stature and gender estimation can be done by using foot measurements and stud y will help in medico - legal cases in establishing identity of an individual and this would be useful for Anatomists and Anthropologists to calculate stature based on foot length

  17. Bond-Length Distortions in Strained Semiconductor Alloys

    International Nuclear Information System (INIS)

    Woicik, J.C.; Pellegrino, J.G.; Steiner, B.; Miyano, K.E.; Bompadre, S.G.; Sorensen, L.B.; Lee, T.; Khalid, S.

    1997-01-01

    Extended x-ray absorption fine structure measurements performed at In-K edge have resolved the outstanding issue of bond-length strain in semiconductor-alloy heterostructures. We determine the In-As bond length to be 2.581±0.004 Angstrom in a buried, 213 Angstrom thick Ga 0.78 In 0.22 As layer grown coherently on GaAs(001). This bond length corresponds to a strain-induced contraction of 0.015±0.004 Angstrom relative to the In-As bond length in bulk Ga 1-x In x As of the same composition; it is consistent with a simple model which assumes a uniform bond-length distortion in the epilayer despite the inequivalent In-As and Ga-As bond lengths. copyright 1997 The American Physical Society

  18. Investigations on quantum mechanics with minimal length

    International Nuclear Information System (INIS)

    Chargui, Yassine

    2009-01-01

    We consider a modified quantum mechanics where the coordinates and momenta are assumed to satisfy a non-standard commutation relation of the form( X i , P j ) = iℎ(δ ij (1+βP 2 )+β'P i P j ). Such an algebra results in a generalized uncertainty relation which leads to the existence of a minimal observable length. Moreover, it incorporates an UV/IR mixing and non commutative position space. We analyse the possible representations in terms of differential operators. The latter are used to study the low energy effects of the minimal length by considering different quantum systems : the harmonic oscillator, the Klein-Gordon oscillator, the spinless Salpeter Coulomb problem, and the Dirac equation with a linear confining potential. We also discuss whether such effects are observable in precision measurements on a relativistic electron trapped in strong magnetic field.

  19. Length of a Hanging Cable

    Directory of Open Access Journals (Sweden)

    Eric Costello

    2011-01-01

    Full Text Available The shape of a cable hanging under its own weight and uniform horizontal tension between two power poles is a catenary. The catenary is a curve which has an equation defined by a hyperbolic cosine function and a scaling factor. The scaling factor for power cables hanging under their own weight is equal to the horizontal tension on the cable divided by the weight of the cable. Both of these values are unknown for this problem. Newton's method was used to approximate the scaling factor and the arc length function to determine the length of the cable. A script was written using the Python programming language in order to quickly perform several iterations of Newton's method to get a good approximation for the scaling factor.

  20. Impact of Cyclic Prefix length on OFDM system Capacity

    DEFF Research Database (Denmark)

    Rom, Christian; Sørensen, Troels Bundgaard; Mogensen, Preben Elgaard

    2005-01-01

    This paper is a study on the impact of the Cyclic Prefix (CP) length on the downlink Capacity in a base-band synchronized SISO-OFDM context. To measure this impact, the capacity, measured in bits per second per hertz, is chosen as quality parameter. The study shows how the lengthening of the CP......) the useful OFDM symbol duration, 2) the Signal to Noise Ratio (SNR) at the receiver and 3) the channel Power Delay Profile (PDP). Depending on the values of these parameters different optimum CP lengths are obtained. For a system using only one value of CP length we suggest an optimum value to be 4us...... for an OFDM symbol length of 40us and 6us for an OFDM symbol length of 80us....

  1. πK-scattering lengths

    International Nuclear Information System (INIS)

    Volkov, M.K.; Osipov, A.A.

    1983-01-01

    The msub(π)asub(0)sup(1/2)=0.1, msub(π)asub(0)sup(3/2)=-0.1, msub(π)asub(0)sup((-))=0.07, msub(π)sup(3)asub(1)sup(1/2)=0.018, msub(π)sup(3)asub(1)aup(3/2)=0.002, msub(π)sup(3)asub(1)sup((-))=0.0044, msub(π)sup(5)asub(2)sup(1/2)=2.4x10sup(-4) and msub(π)sup(5)asub(2)sup(3/2)=-1.2x10sup(-4) scattering lengths are calculated in the framework of the composite meson model which is based on four-quark interaction. The decay form factors of (rho, epsilon, S*) → 2π, (K tilde, K*) → Kπ are used. The q 2 -terms of the quark box diagrams are taken into account. It is shown that the q 2 -terms of the box diagrams give the main contribution to the s-wave scattering lengths. The diagrams with the intermediate vector mesons begin to play the essential role at calculation of the p- and d-wave scattering lengths

  2. Ultrasonographic assessment of renal length in 310 Turkish children ...

    African Journals Online (AJOL)

    Ultrasonography is a non-invasive modality that can be used to measure RL.[2] ... cases were selected for inclusion in the study. Ultrasonography was ... Linear regression equations for predicting a variable (renal length) from independent ...

  3. How much DNA is lost? Measuring DNA loss of short-tandem-repeat length fragments targeted by the PowerPlex 16® system using the Qiagen MinElute Purification Kit.

    Science.gov (United States)

    Kemp, Brian M; Winters, Misa; Monroe, Cara; Barta, Jodi Lynn

    2014-01-01

    The success in recovering genetic profiles from aged and degraded biological samples is diminished by fundamental aspects of DNA extraction, as well as its long-term preservation, that are not well understood. While numerous studies have been conducted to determine whether one extraction method was superior to others, nearly all of them were initiated with no knowledge of the actual starting DNA quantity in the samples prior to extraction, so they ultimately compared the outcome of all methods relative to the best. Using quantitative PCR to estimate the copy count of synthetic standards before (i.e., "copies in") and after (i.e., "copies out") purification by the Qiagen MinElute PCR Purification Kit, we documented DNA loss within a pool of 16 different-sized fragments ranging from 106 to 409 bp in length, corresponding to those targeted by the PowerPlex 16 System (Promega, Madison, WI). Across all standards from 10(4) to 10(7) copies/μL, loss averaged between 21.75% and 60.56% (mean, 39.03%), which is not congruent with Qiagen's claim that 80% of 70 bp to 4 kb fragments are retained using this product (i.e., 20% loss). Our study also found no clear relationship either between DNA strand length and retention or between starting copy number and retention. This suggests that there is no molecule bias across the MinElute column membrane and highlights the need for manufacturers to clearly and accurately describe on what their claims are based, and should also encourage researchers to document DNA retention efficiencies of their own methods and protocols. Understanding how and where to reduce loss of molecules during extraction and purification will serve to generate clearer and more accurate data, which will enhance the utility of ancient and low-copy-number DNA as a tool for closing forensic cases or in reconstructing the evolutionary history of humans and other organisms.

  4. Diagnostic value of newborn foot length to predict gestational age

    Directory of Open Access Journals (Sweden)

    Mutia Farah Fawziah

    2017-08-01

    Full Text Available Background  Identification of gestational age, especially within 48 hours of birth, is crucial for newborns, as the earlier preterm status is detected, the earlier the child can receive optimal management. Newborn foot length is an anthropometric measurement which is easy to perform, inexpensive, and potentially efficient for predicting gestational age. Objective  To analyze the diagnostic value of newborn foot length in predicting gestational age. Methods  This diagnostic study was performed between October 2016 and February 2017 in the High Care Unit of Neonates at Dr. Moewardi General Hospital, Surakarta. A total of 152 newborns were consecutively selected and underwent right foot length measurements before 96 hours of age. The correlation between newborn foot length to classify as full term and gestational age was analyzed with Spearman’s correlation test because of non-normal data distribution. The cut-off point of newborn foot length was calculated by receiver operating characteristic (ROC curve and diagnostic values of newborn foot length were analyzed by 2 x 2 table with SPSS 21.0 software. Results There were no significant differences between male and female newborns in terms of gestational age, birth weight, choronological age, and newborn foot length (P>0.05. Newborn foot length and gestational age had a significant correlation (r=0.53; P=0.000. The optimal cut-off newborn foot length to predict full term status was 7.1 cm. Newborn foot length below 7.1 cm had sensitivity 75%, specificity 98%, positive predictive value 94.3%, negative predictive value 90.6%, positive likelihood ratio 40.5, negative likelihood ratio 0.25, and post-test probability 94.29%, to predict preterm status in newborns. Conclusion  Newborn foot length can be used to predict gestational age, especially for the purpose of differentiating between preterm and full term newborns.

  5. Length of urethra in the Indian adult male population

    Directory of Open Access Journals (Sweden)

    Venkatesh Krishnamoorthy

    2012-01-01

    Full Text Available Objective: The urethral length has not been measured in the Indian population. Even the international literature in this arena is very sparse. This paper is an attempt to develop a simple anatomical database for urethral length. Materials and Methods: Between January 2010 and April 2011, the urethral lengths of 422 adult male patients who required catheterization as part of regular treatment at our hospital, were recorded after obtaining consent from the patients and from the scientific and ethics review boards of the institution. Patients with history of prostatic or urethral abnormalities were excluded. The balloon of a sterile Foley′s catheter was inflated using 10 cc of saline. The length from the junction of the balloon to the ′Y′ junction of the Foley was measured. The catheter was then passed into the bladder and re-inflated to same volume. The penis was gently straightened and the length of the catheter outside the penis was measured till the premarked point at the ′Y′ junction. Subtracting this from the original length gave the length of the urethra. Results: The mean length of the urethra was 17.55 + 1.42 cm with a range between 14 and 22.5 cm. Conclusions: Literature in which the length of the normal adult male urethra is recorded for a significant sample size is very scarce. Our data adds to basic anatomic information of the male urethra specific to the Indian population. Statistical Methods: Descriptive statistical analysis was performed. The non-linear regression analysis was employed to find the normative values of urethral length according to age class.

  6. Determination of the mean free path of the thermal neutrons transport by the measure of a complex diffusion length; Determination du libre parcours moyen de transport des neutrons thermiques par la mesure d'une longueur de diffusion complexe

    Energy Technology Data Exchange (ETDEWEB)

    Raievski, V; Horowitz, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1955-07-01

    The further method is the outcome of a technique used in the study of neutrons in scattering and slowing-down environment. In this technique, we replace the constant sources used in the classic experiences by modulated sources with a variable frequency. The object of this article is to describe the extension of the method for the mean free path for transport of thermal neutrons and also to indicate the possible applications for other sizes, as the slowing length, or the absolute value of the cross-section of the boron. (M.B.) [French] La methode qui va etre decrite est l'aboutissement d'une technique utilisee dans l'etude des milieux ou diffusent et se ralentissent des neutrons. Dans cette technique, on remplace les sources constantes utilisees dans les experiences classiques par des sources modulees, a frequence variable. L'objet de cet article est de decrire l'extension de la methode a la mesure du libre parcours moyen de transport des neutrons thermiques et egalement d'indiquer les applications possibles a la mesure d'autres grandeurs, telles que la longueur de ralentissement, ou la valeur absolue de la section de capture du bore. (M.B.)

  7. Information content versus word length in random typing

    International Nuclear Information System (INIS)

    Ferrer-i-Cancho, Ramon; Moscoso del Prado Martín, Fermín

    2011-01-01

    Recently, it has been claimed that a linear relationship between a measure of information content and word length is expected from word length optimization and it has been shown that this linearity is supported by a strong correlation between information content and word length in many languages (Piantadosi et al 2011 Proc. Nat. Acad. Sci. 108 3825). Here, we study in detail some connections between this measure and standard information theory. The relationship between the measure and word length is studied for the popular random typing process where a text is constructed by pressing keys at random from a keyboard containing letters and a space behaving as a word delimiter. Although this random process does not optimize word lengths according to information content, it exhibits a linear relationship between information content and word length. The exact slope and intercept are presented for three major variants of the random typing process. A strong correlation between information content and word length can simply arise from the units making a word (e.g., letters) and not necessarily from the interplay between a word and its context as proposed by Piantadosi and co-workers. In itself, the linear relation does not entail the results of any optimization process. (letter)

  8. Evaluation of Efficient Line Lengths for Better Readability

    Directory of Open Access Journals (Sweden)

    Zahid Hussain

    2012-01-01

    Full Text Available In this paper the major findings of a formal experiment about onscreen text line lengths are presented. The experiment examined the effects of four different line lengths on the reading speed and the reading efficiency. Efficiency is defined as a combination of reading speed and accuracy. Sixteen people between the age of 24 and 36 participated at the experiment. The subjects had to read four different texts with an average line length around 2000 characters. The texts contained substitution words, which had to be detected by the subjects to measure reading accuracy. Besides objective measures like reading speed and accuracy, the subjects were asked to subjectively vote on their reading experience. The results from our objective measures show strong similarities to those of the work done previously by different researchers. The absolute reading speed grows when the line length grows from CPL (Characters Per Line 30-120. The measured reading efficiency, however, doesn\\\\\\'t grow steadily, although a growing trend can be seen. This is due to the fact, that the test persons found in average more substitution words from the 60 CPL text than they did from the 30 and 90 CPL texts. The reading speed seems to increase while the line length increases but the overall comprehension seems to peak at medium line lengths. As in the previous studies, our test persons also prefer the medium (60 and 90 CPL line lengths, although they perform better when reading longer lines. In the overall subjective opinion 13 out of 16 test persons selected the 60 or 90 CPL line length as their favorite. The literature doesn\\\\\\'t truly provide a scientific explanation for the difference between the objective performance and the subjective preference. A natural hypothesis would be that the line length that is the fastest to read would also feel most comfortable to the readers but in the light of this and the earlier research it seems like this is not the case.

  9. Electron Bunch Length Diagnostic With Coherent Smith-Purcell Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, D.C.

    1997-05-12

    The authors have designed a new technique for measuring subpicosecond electron bunch lengths using coherent Smith-Purcell radiation. This new diagnostic technique involves passing the electron beam in close proximity of a grating with a period comparable to the electron bunch length. The emitted Smith-Purcell radiation will have a coherent component whose angular position and distribution are directly related to the electron bunch length and longitudinal profile, respectively. This new diagnostic technique is inherently simple, inexpensive and non-intercepting. The authors show that the new technique is also scaleable to femtosecond regime.

  10. Electron Bunch Length Diagnostic With Coherent Smith-Purcell Radiation

    International Nuclear Information System (INIS)

    Nguyen, D.C.

    1997-01-01

    The authors have designed a new technique for measuring subpicosecond electron bunch lengths using coherent Smith-Purcell radiation. This new diagnostic technique involves passing the electron beam in close proximity of a grating with a period comparable to the electron bunch length. The emitted Smith-Purcell radiation will have a coherent component whose angular position and distribution are directly related to the electron bunch length and longitudinal profile, respectively. This new diagnostic technique is inherently simple, inexpensive and non-intercepting. The authors show that the new technique is also scaleable to femtosecond regime

  11. An Assessment of the Length and Variability of Mercury's Magnetotail

    Science.gov (United States)

    Milan, S. E.; Slavin, J. A.

    2011-01-01

    We employ Mariner 10 measurements of the interplanetary magnetic field in the vicinity of Mercury to estimate the rate of magnetic reconnection between the interplanetary magnetic field and the Hermean magnetosphere. We derive a time-series of the open magnetic flux in Mercury's magnetosphere. from which we can deduce the length of the magnetotail The length of the magnetotail is shown to be highly variable. with open field lines stretching between 15R(sub H) and 8S0R(sub H) downstream of the planet (median 150R(sub H)). Scaling laws allow the tail length at perihelion to be deduced from the aphelion Mariner 10 observations.

  12. Direct measurement of the centre of mass location in walking persons

    African Journals Online (AJOL)

    h-1 on a motorised treadmill are presented. These data are the first direct measurements of COM oscillation in walking humans over an entire stride. Data found using other, less direct methods are not dissimilar to the data obtained for COM ...

  13. An on-ice measurement approach to analyse the biomechanics of ice hockey skating.

    Directory of Open Access Journals (Sweden)

    Erica Buckeridge

    Full Text Available Skating is a fundamental movement in ice hockey; however little research has been conducted within the field of hockey skating biomechanics due to the difficulties of on-ice data collection. In this study a novel on-ice measurement approach was tested for reliability, and subsequently implemented to investigate the forward skating technique, as well as technique differences across skill levels. Nine high caliber (High and nine low caliber (Low hockey players performed 30 m forward skating trials. A 3D accelerometer was mounted to the right skate for the purpose of stride detection, with the 2nd and 6th strides defined as acceleration and steady-state, respectively. The activity of five lower extremity muscles was recorded using surface electromyography. Biaxial electro-goniometers were used to quantify hip and knee angles, and in-skate plantar force was measured using instrumented insoles. Reliability was assessed with the coefficient of multiple correlation, which demonstrated moderate (r>0.65 to excellent (r>0.95 scores across selected measured variables. Greater plantar-flexor muscle activity and hip extension were evident during acceleration strides, while steady state strides exhibited greater knee extensor activity and hip abduction range of motion (p<0.05. High caliber exhibited greater hip range of motion and forefoot force application (p<0.05. The successful implementation of this on-ice mobile measurement approach offers potential for athlete monitoring, biofeedback and training advice.

  14. An on-ice measurement approach to analyse the biomechanics of ice hockey skating.

    Science.gov (United States)

    Buckeridge, Erica; LeVangie, Marc C; Stetter, Bernd; Nigg, Sandro R; Nigg, Benno M

    2015-01-01

    Skating is a fundamental movement in ice hockey; however little research has been conducted within the field of hockey skating biomechanics due to the difficulties of on-ice data collection. In this study a novel on-ice measurement approach was tested for reliability, and subsequently implemented to investigate the forward skating technique, as well as technique differences across skill levels. Nine high caliber (High) and nine low caliber (Low) hockey players performed 30 m forward skating trials. A 3D accelerometer was mounted to the right skate for the purpose of stride detection, with the 2nd and 6th strides defined as acceleration and steady-state, respectively. The activity of five lower extremity muscles was recorded using surface electromyography. Biaxial electro-goniometers were used to quantify hip and knee angles, and in-skate plantar force was measured using instrumented insoles. Reliability was assessed with the coefficient of multiple correlation, which demonstrated moderate (r>0.65) to excellent (r>0.95) scores across selected measured variables. Greater plantar-flexor muscle activity and hip extension were evident during acceleration strides, while steady state strides exhibited greater knee extensor activity and hip abduction range of motion (p<0.05). High caliber exhibited greater hip range of motion and forefoot force application (p<0.05). The successful implementation of this on-ice mobile measurement approach offers potential for athlete monitoring, biofeedback and training advice.

  15. To the problem of the coherence length of neutrons

    International Nuclear Information System (INIS)

    Varga, P.

    1992-11-01

    The challenge of the high accuracy of certain optical measurements, the long coherence length of light provokes one to search for possibilities to enlarge the neutron coherence length. A proposal is made to achieve this by using a five or a four plate Bonse-Hart interferometer. A further problem is, whether the neutron beam is composed of wave packets or of overlapping independent monochromatic waves; it is considered that the former is more likely. (author) 12 refs.; 3 figs

  16. Quantum discord length is enhanced while entanglement length is not by introducing disorder in a spin chain.

    Science.gov (United States)

    Sadhukhan, Debasis; Roy, Sudipto Singha; Rakshit, Debraj; Prabhu, R; Sen De, Aditi; Sen, Ujjwal

    2016-01-01

    Classical correlation functions of ground states typically decay exponentially and polynomially, respectively, for gapped and gapless short-range quantum spin systems. In such systems, entanglement decays exponentially even at the quantum critical points. However, quantum discord, an information-theoretic quantum correlation measure, survives long lattice distances. We investigate the effects of quenched disorder on quantum correlation lengths of quenched averaged entanglement and quantum discord, in the anisotropic XY and XYZ spin glass and random field chains. We find that there is virtually neither reduction nor enhancement in entanglement length while quantum discord length increases significantly with the introduction of the quenched disorder.

  17. Dorsal Phalloplasty to Preserve Penis Length after Penile Prosthesis Implantation

    Directory of Open Access Journals (Sweden)

    Osama Shaeer

    2017-03-01

    Full Text Available Objectives: Following penile prosthesis implantation (PPI, patients may complain of a decrease in visible penis length. A dorsal phalloplasty defines the penopubic junction by tacking pubic skin to the pubis, revealing the base of the penis. This study aimed to evaluate the efficacy of a dorsal phalloplasty in increasing the visible penis length following PPI. Methods: An inflatable penile prosthesis was implanted in 13 patients with severe erectile dysfunction (ED at the Kamal Shaeer Hospital, Cairo, Egypt, from January 2013 to May 2014. During the surgery, nonabsorbable tacking sutures were used to pin the pubic skin to the pubis through the same penoscrotal incision. Intraoperative penis length was measured before and after the dorsal phalloplasty. Overall patient satisfaction was measured on a 5-point rating scale and patients were requested to subjectively compare their postoperative penis length with memories of their penis length before the onset of ED. Results: Intraoperatively, the dorsal phalloplasty increased the visible length of the erect penis by an average of 25.6%. The average length before and after tacking was 10.2 ± 2.9 cm and 13.7 ± 2.8 cm, respectively (P <0.002. Postoperatively, seven patients (53.8% reported a longer penis, five patients (38.5% reported no change in length and one patient (7.7% reported a slightly shorter penis. The mean overall patient satisfaction score was 4.9 ± 0.3. None of the patients developed postoperative complications. Conclusion: A dorsal phalloplasty during PPI is an effective method of increasing visible penis length, therefore minimising the impression of a shorter penis after implantation.

  18. System for automatic gauge block length measurement optimized for secondary length metrology

    Czech Academy of Sciences Publication Activity Database

    Buchta, Zdeněk; Šarbort, Martin; Čížek, Martin; Hucl, Václav; Řeřucha, Šimon; Pikálek, Tomáš; Dvořáčková, Š.; Dvořáček, F.; Kůr, J.; Konečný, P.; Weigl, M.; Lazar, Josef; Číp, Ondřej

    2017-01-01

    Roč. 49, JULY (2017), s. 322-331 ISSN 0141-6359 R&D Projects: GA TA ČR(CZ) TA03010663; GA MŠk(CZ) LO1212; GA MŠk ED0017/01/01 Institutional support: RVO:68081731 Keywords : low-coherence interferometry * laser interferometry * Gauge block * metrology Subject RIV: BH - Optics, Masers, Laser s OBOR OECD: Optics (including laser optics and quantum optics) Impact factor: 2.237, year: 2016

  19. Sub-recoil cooling up to nano-Kelvin. Direct measurement of spatial coherency length. New tests for Levy statistics; Refroidissement laser subrecul au nanokelvin. Mesure directe de la longueur de coherence spatiale. Nouveaux tests des statistiques de Levy

    Energy Technology Data Exchange (ETDEWEB)

    Saubamea, B

    1998-12-15

    This thesis presents a new method to measure the temperature of ultracold atoms from the spatial autocorrelation function of the atomic wave-packets. We thus determine the temperature of metastable helium-4 atoms cooled by velocity selective dark resonance, a method known to cool the atoms below the temperature related to the emission or the absorption of a single photon by an atom at rest, namely the recoil temperature. This cooling mechanism prepares each atom in a coherent superposition of two wave-packets with opposite mean momenta, which are initially superimposed and then drift apart. By measuring the temporal decay of their overlap, we have access to the Fourier transform of the momentum distribution of the atoms. Using this method, we can measure temperatures as low as 5 nK, 800 times as small as the recoil temperature. Moreover we study in detail the exact shape of the momentum distribution and compare the experimental results with two different theoretical approaches: a quantum Monte Carlo simulation and an analytical model based on Levy statistics. We compare the calculated line shape with the one deduced from simulations, and each theoretical model with experimental data. A very good agreement is found with each approach. We thus demonstrate the validity of the statistical model of sub-recoil cooling and give the first experimental evidence of some of its characteristics: the absence of steady-state, the self-similarity and the non Lorentzian shape of the momentum distribution of the cooled atoms. All these aspects are related to the non ergodicity of sub-recoil cooling. (author)

  20. Measurement

    NARCIS (Netherlands)

    Boumans, M.; Durlauf, S.N.; Blume, L.E.

    2008-01-01

    Measurement theory takes measurement as the assignment of numbers to properties of an empirical system so that a homomorphism between the system and a numerical system is established. To avoid operationalism, two approaches can be distinguished. In the axiomatic approach it is asserted that if the

  1. Musculoskeletal pain and posture decrease step length in young adults

    Directory of Open Access Journals (Sweden)

    Maria Regina Rachmawati

    2009-08-01

    Full Text Available Pain of the musculoskeletal system, especially low back pain, is one of the most frequent problems with a high risk of disability. The aim of this research study was to determine the existence of an association between low back pain on one hand, posture and step length on the other. This cross-sectional study was conducted on 77 healthy young adult subjects. Step length was measured with the Biodex Gait Trainer 2 (230 VAC. The study results indicate that 62.3% of the young adult subjects had suffered from low back pain. There was no significant association between gender and pain. In male subjects no significant association was found between pain on one hand and mean difference in step length and posture on the other. However, in female subjects with abnormal posture, there was a highly significant difference in left step length between subjects with back pain and those without (p=0.007. The results of a multiple regression analysis indicate that posture has the greatest influence on left step length (B=4.135; 95% Confidence Interval 0.292-7.977. It is recommended that in the examination of low back pain an assessment be made of posture, step length and difference in step lengths.

  2. Musculoskeletal pain and posture decrease step length in young adults

    Directory of Open Access Journals (Sweden)

    Maria Regina Rachmawati

    2016-02-01

    Full Text Available Pain of the musculoskeletal system, especially low back pain, is one of the most frequent problems with a high risk of disability. The aim of this research study was to determine the existence of an association between low back pain on one hand,  posture and step length on the other. This cross-sectional study was conducted on 77 healthy young adult subjects. Step length was measured with the Biodex Gait Trainer 2 (230 VAC. The study results indicate that 62.3% of the young adult subjects had suffered from low back pain. There was no significant association between gender and pain. In male subjects no significant association was found between pain on one hand and mean difference in step length and posture on the other. However, in female subjects with abnormal posture, there was a highly significant difference in left step length between subjects with back pain and those without (p=0.007.  The results of a multiple regression analysis indicate that posture has the greatest influence on left step length (B=4.135; 95% Confidence Interval 0.292-7.977. It is recommended that in the examination of low back pain an assessment be made of posture, step length and difference in step lengths.

  3. Evaluating Multispectral Snowpack Reflectivity With Changing Snow Correlation Lengths

    Science.gov (United States)

    Kang, Do Hyuk; Barros, Ana P.; Kim, Edward J.

    2016-01-01

    This study investigates the sensitivity of multispectral reflectivity to changing snow correlation lengths. Matzler's ice-lamellae radiative transfer model was implemented and tested to evaluate the reflectivity of snow correlation lengths at multiple frequencies from the ultraviolet (UV) to the microwave bands. The model reveals that, in the UV to infrared (IR) frequency range, the reflectivity and correlation length are inversely related, whereas reflectivity increases with snow correlation length in the microwave frequency range. The model further shows that the reflectivity behavior can be mainly attributed to scattering rather than absorption for shallow snowpacks. The largest scattering coefficients and reflectivity occur at very small correlation lengths (approximately 10(exp -5 m) for frequencies higher than the IR band. In the microwave range, the largest scattering coefficients are found at millimeter wavelengths. For validation purposes, the ice-lamella model is coupled with a multilayer snow physics model to characterize the reflectivity response of realistic snow hydrological processes. The evolution of the coupled model simulated reflectivities in both the visible and the microwave bands is consistent with satellite-based reflectivity observations in the same frequencies. The model results are also compared with colocated in situ snow correlation length measurements (Cold Land Processes Field Experiment 2002-2003). The analysis and evaluation of model results indicate that the coupled multifrequency radiative transfer and snow hydrology modeling system can be used as a forward operator in a data-assimilation framework to predict the status of snow physical properties, including snow correlation length.

  4. Assessment of colorectal length using the electromagnetic capsule tracking system

    DEFF Research Database (Denmark)

    Mark, E B; Poulsen, J L; Haase, A M

    2017-01-01

    AIM: We aimed to determine colorectal length with the 3D-Transit system by describing a 'centerline' of capsule movement and compare it to known anatomy, as determined by magnetic resonance imaging (MRI). Further, we aimed to test the day-to-day variation of colorectal length assessed......: Computation of colorectal length from capsule passage was possible in 60 of the 67 3D-Transit recordings. Length of the colorectum measured with MRI and 3D-Transit was respectively 95 cm (75-153 cm) and 99 cm (77-147 cm), P = 0.15. Coefficient of variation (CV) between MRI and 3D-Transit was 7.8%. Apart from...... the cecum / ascending colon being 26% (P = 0.002) shorter on MRI, there were no other differences in total or segmental colorectal lengths between methods (all P > 0.05). Length of the colorectum measured with 3D-Transit on two consecutive days was 102 cm (73-119 cm) and 103 cm (75-123 cm), P = 0.67. CV...

  5. Television Watching and Telomere Length Among Adults in Southwest China.

    Science.gov (United States)

    Xue, Hong-Mei; Liu, Qian-Qian; Tian, Guo; Quan, Li-Ming; Zhao, Yong; Cheng, Guo

    2017-09-01

    To explore the independent associations of sedentary behavior and physical activity with telomere length among Chinese adults. Data on total time of sedentary behavior, screen-based sedentary behavior (including television watching and computer or phone use), moderate to vigorous physical activity, and dietary intake of 518 adults in Chengdu, Guizhou, and Xiamen in China (54.25% women) aged 20 to 70 years were obtained between 2013 and 2015 through questionnaires. Height, weight, and waist circumference were measured to calculate body mass index and percentage of body fat. Telomere length was measured through Southern blot technique. Television watching was inversely related to adjusted telomere length (-71.75 base pair; SE = 34.40; P  = .04). Furthermore, a similar trend between telomere length and television watching was found in the group aged 20 to 40 years after adjusting for all covariates. Adults aged 20 to 40 years in the highest tertile of daily time spent on watching television had 4.0% shorter telomere length than adults in the lowest tertile (P = .03). Although the association is modest, television watching is inversely related to telomere length among Chinese adults, warranting further investigation in large prospective studies.

  6. Study on effective MOSFET channel length extracted from gate capacitance

    Science.gov (United States)

    Tsuji, Katsuhiro; Terada, Kazuo; Fujisaka, Hisato

    2018-01-01

    The effective channel length (L GCM) of metal-oxide-semiconductor field-effect transistors (MOSFETs) is extracted from the gate capacitances of actual-size MOSFETs, which are measured by charge-injection-induced-error-free charge-based capacitance measurement (CIEF CBCM). To accurately evaluate the capacitances between the gate and the channel of test MOSFETs, the parasitic capacitances are removed by using test MOSFETs having various channel sizes and a source/drain reference device. A strong linear relationship between the gate-channel capacitance and the design channel length is obtained, from which L GCM is extracted. It is found that L GCM is slightly less than the effective channel length (L CRM) extracted from the measured MOSFET drain current. The reason for this is discussed, and it is found that the capacitance between the gate electrode and the source and drain regions affects this extraction.

  7. Naloxone fails to prolong seizure length in ECT.

    Science.gov (United States)

    Rasmussen, K G; Pandurangi, A K

    1999-12-01

    Electroconvulsive shock (ECS) in animals has been shown to enhance endogenous opiate systems. The anticonvulsant effects of ECS are also partially blocked by the opiate receptor antagonist naloxone, leading some investigators to postulate that the anticonvulsant effects of ECS are mediated by activation of endogenous opiates. If such a phenomenon occurs in humans, then naloxone might prolong seizure length in electroconvulsive therapy (ECT). In the present study, nine patients were given 2.0 mg intravenous (i.v.) naloxone 2 minutes prior to one-half of their ECT treatments. Motor seizure length was measured via the cuff technique. EEG tracings were read by an investigator blind to naloxone status. There was no difference between the two groups in either EEG or nonblindly evaluated motor seizure length. It is concluded that a dose of 2 mg naloxone does not effectively increase seizure length in ECT.

  8. The length of the glaciers in the world

    DEFF Research Database (Denmark)

    Machguth, Horst; Huss, M.; Huss, M.

    2014-01-01

    a fully automated method based on glacier surface slope, distance to the glacier margins and a set of trade-off functions. The method is developed for East Greenland, evaluated for the same area as well as for Alaska, and eventually applied to all ∼ 200000 glaciers around the globe. The evaluation...... highlights accurately calculated glacier length where DEM quality is good (East 10 Greenland) and limited precision on low quality DEMs (parts of Alaska). Measured length of very small glaciers is subject to a certain level of ambiguity. The global calculation shows that only about 1.5% of all glaciers...... are longer than 10km with Bering Glacier (Alaska/Canada) being the longest glacier in the world at a length of 196 km. Based on model output we derive global and regional area-length scaling laws. Differences among regional scaling parameters appear to be related to characteristics of topography and glacier...

  9. Finite length thermal equilibria of a pure electron plasma column

    International Nuclear Information System (INIS)

    Prasad, S.A.; O'Neil, T.M.

    1979-01-01

    The electrons of a pure electron plasma may be in thermal equilibrium with each other and still be confined by static magnetic and electric fields. Since the electrons make a significant contribution to the electric field, only certain density profiles are consistent with Poisson's equation. The class of such distributions for a finite length cylindrical column is investigated. In the limit where the Debye length is small compared with the dimensions of the column, the density is essentially constant out to some surface of revolution and then falls off abruptly. The falloff in density is a universal function when measured along the local normal to the surface of revolution and scaled in terms of the Debye length. The solution for the shape of the surface of revolution is simplified by passage to the limit of zero Debye length

  10. Telomere Length – a New Biomarker in Medicine

    Directory of Open Access Journals (Sweden)

    Agnieszka Kozłowska

    2015-12-01

    Full Text Available A number of xenobiotics in the environment and workplace influences on our health and life. Biomarkers are tools for measuring such exposures and their effects in the organism. Nowadays, telomere length, epigenetic changes, mutations and changes in gene expression pattern have become new molecular biomarkers. Telomeres play the role of molecular clock, which influences on expectancy of cell life and thus aging, the formation of damages, development diseases and carcinogenesis. The telomere length depends on mechanisms of replication and the activity of telomerase. Telomere length is currently used as a biomarker of susceptibility and/or exposure. This paper describes the role of telomere length as a biomarker of aging cells, oxidative stress, a marker of many diseases including cancer, and as a marker of environmental and occupational exposure.

  11. Focal Length Affects Depicted Shape and Perception of Facial Images.

    Directory of Open Access Journals (Sweden)

    Vít Třebický

    Full Text Available Static photographs are currently the most often employed stimuli in research on social perception. The method of photograph acquisition might affect the depicted subject's facial appearance and thus also the impression of such stimuli. An important factor influencing the resulting photograph is focal length, as different focal lengths produce various levels of image distortion. Here we tested whether different focal lengths (50, 85, 105 mm affect depicted shape and perception of female and male faces. We collected three portrait photographs of 45 (22 females, 23 males participants under standardized conditions and camera setting varying only in the focal length. Subsequently, the three photographs from each individual were shown on screen in a randomized order using a 3-alternative forced-choice paradigm. The images were judged for attractiveness, dominance, and femininity/masculinity by 369 raters (193 females, 176 males. Facial width-to-height ratio (fWHR was measured from each photograph and overall facial shape was analysed employing geometric morphometric methods (GMM. Our results showed that photographs taken with 50 mm focal length were rated as significantly less feminine/masculine, attractive, and dominant compared to the images taken with longer focal lengths. Further, shorter focal lengths produced faces with smaller fWHR. Subsequent GMM revealed focal length significantly affected overall facial shape of the photographed subjects. Thus methodology of photograph acquisition, focal length in this case, can significantly affect results of studies using photographic stimuli perhaps due to different levels of perspective distortion that influence shapes and proportions of morphological traits.

  12. Comparison of a clinical gait analysis method using videography and temporal-distance measures with 16-mm cinematography.

    Science.gov (United States)

    Stuberg, W A; Colerick, V L; Blanke, D J; Bruce, W

    1988-08-01

    The purpose of this study was to compare a clinical gait analysis method using videography and temporal-distance measures with 16-mm cinematography in a gait analysis laboratory. Ten children with a diagnosis of cerebral palsy (means age = 8.8 +/- 2.7 years) and 9 healthy children (means age = 8.9 +/- 2.4 years) participated in the study. Stride length, walking velocity, and goniometric measurements of the hip, knee, and ankle were recorded using the two gait analysis methods. A multivariate analysis of variance was used to determine significant differences between the data collected using the two methods. Pearson product-moment correlation coefficients were determined to examine the relationship between the measurements recorded by the two methods. The consistency of performance of the subjects during walking was examined by intraclass correlation coefficients. No significant differences were found between the methods for the variables studied. Pearson product-moment correlation coefficients ranged from .79 to .95, and intraclass coefficients ranged from .89 to .97. The clinical gait analysis method was found to be a valid tool in comparison with 16-mm cinematography for the variables that were studied.

  13. Full length prototype SSC dipole test results

    International Nuclear Information System (INIS)

    Strait, J.; Brown, B.C.; Carson, J.

    1987-01-01

    Results are presented from tests of the first full length prototype SSC dipole magnet. The cryogenic behavior of the magnet during a slow cooldown to 4.5K and a slow warmup to room temperature has been measured. Magnetic field quality was measured at currents up to 2000 A. Averaged over the body field all harmonics with the exception of b 2 and b 8 are at or within the tolerances specified by the SSC Central Design Group. (The values of b 2 and b 8 result from known design and construction defects which will be be corrected in later magnets.) Using an NMR probe the average body field strength is measured to be 10.283 G/A with point to point variations on the order of one part in 1000. Data are presented on quench behavior of the magnet up to 3500 A (approximately 55% of full field) including longitudinal and transverse velocities for the first 250 msec of the quench

  14. Tree Diamter Effects on Cost and Productivity of Cut-to-Length Systems

    Science.gov (United States)

    Matthew A. Holtzscher; Bobby L. Lanford

    1997-01-01

    Currently, there is a lack of economic information concerning cut-to-length harvesting systems. This study examined and measured the different costs of operating cut-to-length logging equipment over a range of average stand diameters at breast height. Three different cut-to-length logging systems were examined in this study. Systems included: 1) felier-buncher/manual/...

  15. Effects of preservation method on length and weight of pond raised ...

    African Journals Online (AJOL)

    Length and weight measurements of fish used for taxonomy and determination of length-weight relationship are taken from preserved specimen. This study sets out to investigate the effects of two preservatives, 70% alcohol and 10% formalin and freezing method on the length and weight of preserved specimens of tilapia ...

  16. The newest precision measurement

    International Nuclear Information System (INIS)

    Lee, Jing Gu; Lee, Jong Dae

    1974-05-01

    This book introduces basic of precision measurement, measurement of length, limit gauge, measurement of angles, measurement of surface roughness, measurement of shapes and locations, measurement of outline, measurement of external and internal thread, gear testing, accuracy inspection of machine tools, three dimension coordinate measuring machine, digitalisation of precision measurement, automation of precision measurement, measurement of cutting tools, measurement using laser, and point of choosing length measuring instrument.

  17. Tagging charm with decay lengths

    International Nuclear Information System (INIS)

    Reay, N.W.

    1982-01-01

    With much detail, the author of this selection discusses two experiments which use the same physics but in different ways to obtain one same goala background - free sample of charm decays. One of the major purposes of gaining this sample is to measure one lifetime for charmed particles and to locate new particles. Continuing to discuss the first experiment, the Fermilab Experiment + 531, the author describes its methods, philosophy and two unexpected effects of the experiment. He turns then to discuss the CERN NA-15 experiment, describing its methods, findings and difficulties. Concluding his discussion on a positive note, the author is hopeful for the plans to continue more experimentation

  18. Father Loss and Child Telomere Length.

    Science.gov (United States)

    Mitchell, Colter; McLanahan, Sara; Schneper, Lisa; Garfinkel, Irv; Brooks-Gunn, Jeanne; Notterman, Daniel

    2017-08-01

    Father loss during childhood has negative health and behavioral consequences, but the biological consequences are unknown. Our goal was to examine how father loss (because of separation and/or divorce, death, or incarceration) is associated with cellular function as estimated by telomere length. Data come from the 9-year follow-up of the Fragile Families and Child Wellbeing Study, a birth cohort study of children in 20 large American cities ( N = 2420). Principal measures are as follows: salivary telomere length (sTL), mother reports of father loss, and polymorphisms in genes related to serotonergic and dopaminergic signaling. At 9 years of age, children with father loss have significantly shorter telomeres (14% reduction). Paternal death has the largest association (16%), followed by incarceration (10%), and separation and/or divorce (6%). Changes in income partially mediate these associations (95% mediation for separation and/or divorce, 30% for incarceration, and 25% for death). Effects are 40% greater for boys and 90% greater for children with the most reactive alleles of the serotonin transporter genes when compared with those with the least reactive alleles. No differences were found by age at father loss or a child's race/ethnicity. Father loss has a significant association with children's sTL, with the death of a father showing the largest effect. Income loss explains most of the association between child sTL and separation and/or divorce but much less of the association with incarceration or death. This underscores the important role of fathers in the care and development of children and supplements evidence of the strong negative effects of parental incarceration. Copyright © 2017 by the American Academy of Pediatrics.

  19. Standardization of methods of expressing lengths and weights of fish

    Science.gov (United States)

    Hile, Ralph

    1948-01-01

    Fishery workers in the United States and Canada are unable to think readily in terms of the metric system of weights and measurements. Even long experience does not make it possible to form a clear idea as to the actual size of fish for which lengths and weights are given in metric units, without first converting to the English system. A more general adoption of the English system of weights and measurements in fishery work is recommended. The use of English units exclusively is suggested for articles of a popular or semi-popular nature, but in more formal publications the key information, at least, should be recorded in both systems. In highly technical papers metric units alone may prove satisfactory. Agreement is also lacking as to which length measurement of fish is suited best for uniform adoption. The total length is recommended here for the reason that it is the only measurement that includes all of the fish. This length is defined as the distance from the tip of the head (jaws closed) to the tip of the tail with the lobes compressed so as to give the maximum possible measurement.

  20. Measuring $\

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, Jessica Sarah [Univ. of Cambridge (United Kingdom)

    2011-01-01

    The MINOS Experiment consists of two steel-scintillator calorimeters, sampling the long baseline NuMI muon neutrino beam. It was designed to make a precise measurement of the ‘atmospheric’ neutrino mixing parameters, Δm2 atm. and sin2 (2 atm.). The Near Detector measures the initial spectrum of the neutrino beam 1km from the production target, and the Far Detector, at a distance of 735 km, measures the impact of oscillations in the neutrino energy spectrum. Work performed to validate the quality of the data collected by the Near Detector is presented as part of this thesis. This thesis primarily details the results of a vμ disappearance analysis, and presents a new sophisticated fitting software framework, which employs a maximum likelihood method to extract the best fit oscillation parameters. The software is entirely decoupled from the extrapolation procedure between the detectors, and is capable of fitting multiple event samples (defined by the selections applied) in parallel, and any combination of energy dependent and independent sources of systematic error. Two techniques to improve the sensitivity of the oscillation measurement were also developed. The inclusion of information on the energy resolution of the neutrino events results in a significant improvement in the allowed region for the oscillation parameters. The degree to which sin2 (2θ )= 1.0 could be disfavoured with the exposure of the current dataset if the true mixing angle was non-maximal, was also investigated, with an improved neutrino energy reconstruction for very low energy events. The best fit oscillation parameters, obtained by the fitting software and incorporating resolution information were: | Δm2| = 2.32+0.12 -0.08×10-3 eV2 and sin2 (2θ ) > 0.90(90% C.L.). The analysis provides the current world best measurement of the atmospheric neutrino mass

  1. Managing carbon sinks by changing rotation length in European forests

    International Nuclear Information System (INIS)

    Kaipainen, Terhi; Liski, Jari; Pussinen, Ari; Karjalainen, Timo

    2004-01-01

    Elongation of rotation length is a forest management activity countries may choose to apply under Article 3.4 of the Kyoto Protocol to help them meet their commitments for reduction of greenhouse gas emissions. We used the CO2FIX model to analyze how the carbon stocks of trees, soil and wood products depend on rotation length in different European forests. Results predicted that the carbon stock of trees increased in each forest when rotation length was increased, but the carbon stock of soil decreased slightly in German and Finnish Scots pine forests; the carbon stock of wood products also decreased slightly in cases other than the Sitka spruce forest in UK. To estimate the efficiency of increasing rotation length as an Article 3.4 activity, we looked at changes in the carbon stock of trees resulting from a 20-year increase in current rotation lengths. To achieve the largest eligible carbon sink mentioned in Article 3.4 of the Kyoto Protocol, the rotation lengths need to be increased on areas varying from 0.3 to 5.1 Mha depending on the forest. This would in some forests cause 1-6% declines in harvesting possibilities. The possible decreases in the carbon stock of soil indicate that reporting the changes in the carbon stocks of forests under Article 3.4 may require measuring soil carbon

  2. Lengths and Positions of the Vermiform Appendix among Sudanese Cadavers

    Directory of Open Access Journals (Sweden)

    Ehab I. El-Amin

    2015-08-01

    Full Text Available Background/objective: The anatomy of vermiform appendix displays great variations in length and position between different populations. The reports relating these variations to a specific etiological factor are few. This study aims to describe the positions and lengths of vermiform appendix among Sudanese cadavers. Methods: This descriptive study was carried out in Omdurman Teaching Hospital Morgue and Omdurman Islamic University-Sudan. Sixty Sudanese cadavers (30 male and 30 female, were dissected in the period from June 2013 to June 2014. The positions and the lengths of vermiform appendix were measured in millimeters. The data was analyzed by SPSS version 20. Results: The cadavers’ age ranged between 20 to 80 years according to their medico-legal reports. Retrocaecal position was mainly observed in 60%, pelvic in 35%, post-ileal in 3.3%, and pre-ileal in 1.7%. The lengths of the appendix was found < 69 mm in 23.3%, 70-110 mm in 60%, and > 110 mm in 16.7%, also the study showed insignificant difference between the lengths and ages (p < 0.08, and between males and females (p = 0.23. Age was the influencing factor for the positions of vermiform appendixes (p = 0.04. Conclusion: The study showed that the commonest lengths of the appendix were 70-110 mm while the common position was retrocaecal regardless to age or gender. This data should be considered in surgical removal of the inflamed appendix.

  3. Short Rayleigh Length Free Electron Lasers

    CERN Document Server

    Crooker, P P; Armstead, R L; Blau, J

    2004-01-01

    Conventional free electron laser (FEL) oscillators minimize the optical mode volume around the electron beam in the undulator by making the resonator Rayleigh length about one third of the undulator length. This maximizes gain and beam-mode coupling. In compact configurations of high-power infrared FELs or moderate power UV FELs, the resulting optical intensity can damage the resonator mirrors. To increase the spot size and thereby reduce the optical intensity at the mirrors below the damage threshold, a shorter Rayleigh length can be used, but the FEL interaction is significantly altered. A new FEL interaction is described and analyzed with a Rayleigh length that is only one tenth the undulator length, or less. The effect of mirror vibration and positioning are more critical in the short Rayleigh length design, but we find that they are still within normal design tolerances.

  4. Length dependent properties of SNS microbridges

    International Nuclear Information System (INIS)

    Sauvageau, J.E.; Jain, R.K.; Li, K.; Lukens, J.E.; Ono, R.H.

    1985-01-01

    Using an in-situ, self-aligned deposition scheme, arrays of variable length SNS junctions in the range of 0.05 μm to 1 μm have been fabricated. Arrays of SNS microbridges of lead-copper and niobium-copper fabricated using this technique have been used to study the length dependence, at constant temperature, of the critical current I and bridge resistance R /SUB d/ . For bridges with lengths pounds greater than the normal metal coherence length xi /SUB n/ (T), the dependence of I /SUB c/ on L is consistent with an exponential dependence on the reduced length l=L/xi /SUB n/ (T). For shorter bridges, deviations from this behavior is seen. It was also found that the bridge resistance R /SUB d/ does not vary linearly with the geometric bridge length but appears to approach a finite value as L→O

  5. Relation between axial length and ocular parameters

    Directory of Open Access Journals (Sweden)

    Xue-Qiu Yang

    2013-09-01

    Full Text Available AIM: To investigatethe relation between axial length(AL, age and ocular parameters.METHODS: A total of 360 subjects(360 eyeswith emmetropia or myopia were recruited. Refraction, center corneal thickness(CCT, AL, intraocular pressure(IOPwere measured by automatic-refractor, Pachymeter, A-mode ultrasound and non-contact tonometer, respectively. Corneal curvature(CC, anterior chamber depth(ACDand white-to-white distance(WWDwere measured by Orbscan II. Three dimensional frequency domain coherent optical tomography(3D-OCTwas used to examine the retinal nerve fiber layer thickness(RNFLT. The Pearson correlation coefficient(rand multiple regression analysis were performed to evaluate the relationship between AL, age and ocular parameters.RESULTS: The average AL was 24.15±1.26mm. With elongation of the AL, spherical equivalent(SE(r=-0.742,Pr=-0.395, Pr=-0.374, Pr=0.411, Pr=0.099, P=0.060and WWD(r=0.061, P=0.252. There was also a significant correlation between AL and age(P=0.001, SE(PPPCONCLUSION: In longer eyes, there is a tendency toward myopia, a flatter cornea, a deeper ACD and a thinner RNFLT. Age is an influencing factor for the AL as well.

  6. Debye screening length effects of nanostructured materials

    CERN Document Server

    Ghatak, Kamakhya Prasad

    2014-01-01

    This monograph solely investigates the Debye Screening Length (DSL) in semiconductors and their nano-structures. The materials considered are quantized structures of non-linear optical, III-V, II-VI, Ge, Te, Platinum Antimonide, stressed materials, Bismuth, GaP, Gallium Antimonide, II-V and Bismuth Telluride respectively. The DSL in opto-electronic materials and their quantum confined counterparts is studied in the presence of strong light waves and intense electric fields on the basis of newly formulated electron dispersion laws that control the studies of such quantum effect devices. The suggestions for the experimental determination of 2D and 3D DSL and the importance of measurement of band gap in optoelectronic materials under intense built-in electric field in nano devices and strong external photo excitation (for measuring photon induced physical properties) have also been discussed in this context. The influence of crossed electric and quantizing magnetic fields on the DSL and the DSL in heavily doped ...

  7. Dither Cavity Length Controller with Iodine Locking

    Directory of Open Access Journals (Sweden)

    Lawson Marty

    2016-01-01

    Full Text Available A cavity length controller for a seeded Q-switched frequency doubled Nd:YAG laser is constructed. The cavity length controller uses a piezo-mirror dither voltage to find the optimum length for the seeded cavity. The piezo-mirror dither also dithers the optical frequency of the output pulse. [1]. This dither in optical frequency is then used to lock to an Iodine absorption line.

  8. Telomere length in normal and neoplastic canine tissues.

    Science.gov (United States)

    Cadile, Casey D; Kitchell, Barbara E; Newman, Rebecca G; Biller, Barbara J; Hetler, Elizabeth R

    2007-12-01

    To determine the mean telomere restriction fragment (TRF) length in normal and neoplastic canine tissues. 57 solid-tissue tumor specimens collected from client-owned dogs, 40 samples of normal tissue collected from 12 clinically normal dogs, and blood samples collected from 4 healthy blood donor dogs. Tumor specimens were collected from client-owned dogs during diagnostic or therapeutic procedures at the University of Illinois Veterinary Medical Teaching Hospital, whereas 40 normal tissue samples were collected from 12 control dogs. Telomere restriction fragment length was determined by use of an assay kit. A histologic diagnosis was provided for each tumor by personnel at the Veterinary Diagnostic Laboratory at the University of Illinois. Mean of the mean TRF length for 44 normal samples was 19.0 kilobases (kb; range, 15.4 to 21.4 kb), and the mean of the mean TRF length for 57 malignant tumors was 19.0 kb (range, 12.9 to 23.5 kb). Although the mean of the mean TRF length for tumors and normal tissues was identical, tumor samples had more variability in TRF length. Telomerase, which represents the main mechanism by which cancer cells achieve immortality, is an attractive therapeutic target. The ability to measure telomere length is crucial to monitoring the efficacy of telomerase inhibition. In contrast to many other mammalian species, the length of canine telomeres and the rate of telomeric DNA loss are similar to those reported in humans, making dogs a compelling choice for use in the study of human anti-telomerase strategies.

  9. Ocular Axial Length Measurement Among Normal Adults Using ...

    African Journals Online (AJOL)

    2017-07-26

    Jul 26, 2017 ... eye is the AL and report from previous studies suggest that in an adult, the average ... 2017 Nigerian Journal of Ophthalmology | Published by Wolters Kluwer - Medknow ..... Parel JM, Gelender H, Trefers WF, Norton EW.

  10. Ocular axial length measurement among normal adults using ...

    African Journals Online (AJOL)

    , as visual compromise is a major consequence if they are not diagnosed and managed appropriately. Aim and Objectives: To use magnetic resonance imaging, to determine the normal AL of the eyeball and to establish the association, if any, ...

  11. Information, polarization and term length in democracy

    DEFF Research Database (Denmark)

    Schultz, Christian

    2008-01-01

    This paper considers term lengths in a representative democracy where the political issue divides the population on the left-right scale. Parties are ideologically different and better informed about the consequences of policies than voters are. A short term length makes the government more...... accountable, but the re-election incentive leads to policy-distortion as the government seeks to manipulate swing voters' beliefs to make its ideology more popular. This creates a trade-off: A short term length improves accountability but gives distortions. A short term length is best for swing voters when...

  12. Sonographic Evaluation of the Splenic Length in Normal Pregnancy ...

    African Journals Online (AJOL)

    Methods: A prospective descriptive cross sectional study of the sonographic measurements of the splenic length was performed on 150 healthy normal pregnant women correlating this with the body mass index, gestational age and parity. Data were analyzed using software SPSS version 15 (SPSS Inc., Chicago, IL, USA).

  13. Heritability of sperm length in the bumblebee Bombus terrestris

    DEFF Research Database (Denmark)

    Baer, Boris; de Jong, Gerdien; Schmid-Hempel, Regula

    2006-01-01

    estimates of narrow sense heritability of sperm length in a social insect, the bumblebee Bombus terrestris. In spite of a balanced and straightforward rearing design of colonies, and the possibility to replicate measurements of sperm within single males nested within colonies, the analysis proved...

  14. A dynamical approach to time dilation and length contraction

    NARCIS (Netherlands)

    Vries, de D.K.; Muynck, de W.M.

    1996-01-01

    Simple models of length and time measuring instruments are studied in order to see under what conditions a relativistic description of the dynamics of accelerated motion can be consistent with the kinematic prescriptions of Lorentz contraction and time dilation. The outcomes obtained for the

  15. Diameter sensors for tree-length harvesting systems

    Science.gov (United States)

    T.P. McDonald; Robert B. Rummer; T.E. Grift

    2003-01-01

    Most cut-to-length (CTL) harvesters provide sensors for measuring diameter of trees as they are cut and processed. Among other uses, this capability provides a data collection tool for marketing of logs in real time. Logs can be sorted and stacked based on up-to-date market information, then transportation systems optimized to route wood to proper destinations at...

  16. Otolith Length-Fish Length Relationships of Eleven US Arctic Fish Species and Their Application to Ice Seal Diet Studies

    Science.gov (United States)

    Walker, K. L.; Norcross, B.

    2016-02-01

    The Arctic ecosystem has moved into the spotlight of scientific research in recent years due to increased climate change and oil and gas exploration. Arctic fishes and Arctic marine mammals represent key parts of this ecosystem, with fish being a common part of ice seal diets in the Arctic. Determining sizes of fish consumed by ice seals is difficult because otoliths are often the only part left of the fish after digestion. Otolith length is known to be positively related to fish length. By developing species-specific otolith-body morphometric relationships for Arctic marine fishes, fish length can be determined for fish prey found in seal stomachs. Fish were collected during ice free months in the Beaufort and Chukchi seas 2009 - 2014, and the most prevalent species captured were chosen for analysis. Otoliths from eleven fish species from seven families were measured. All species had strong linear relationships between otolith length and fish total length. Nine species had coefficient of determination values over 0.75, indicating that most of the variability in the otolith to fish length relationship was explained by the linear regression. These relationships will be applied to otoliths found in stomachs of three species of ice seals (spotted Phoca largha, ringed Pusa hispida, and bearded Erignathus barbatus) and used to estimate fish total length at time of consumption. Fish lengths can in turn be used to calculate fish weight, enabling further investigation into ice seal energetic demands. This application will aid in understanding how ice seals interact with fish communities in the US Arctic and directly contribute to diet comparisons among and within ice seal species. A better understanding of predator-prey interactions in the US Arctic will aid in predicting how ice seal and fish species will adapt to a changing Arctic.

  17. Comparative analysis of maximum renal longitudinal length with positional changes on ultrasound with multiplanar reconstructed MR image in Korea Adults

    International Nuclear Information System (INIS)

    Jang, Yun Hee; Cho, Bum Sang; Kang, Min Ho; Kang, Woo Young; Lee, Jisun; Kim, Yook; Lee, Soo Hyun; Lee, Soo Jung; Lee, Jin Yong

    2016-01-01

    The purpose of this study was to determine a suitable position in which the measured length on ultrasound is close to the true renal length obtained through a multiplanar reconstructed MR image. A total of 33 individuals (males: 15, females: 18) without any underlying renal disease were included in the present study. Renal length was measured as the longest axis at the level of the renal hilum in three positions-supine, lateral decubitus, and prone, respectively. With a 3.0 T MR scanner, 3D eTHRIVE was acquired. Subsequently, the maximum longitudinal length of both the kidneys was measured through multiplanar reconstructed MR images. Paired t-test was used to compare the renal length obtained from ultrasonographic measurement with the length obtained through multiplanar reconstructed MR images. Our study demonstrated significant difference between sonographic renal length in three positions and renal length through MRI (p < 0.001). However, the longest longitudinal length of right kidney among the measured three values by ultrasound was statistically similar to the renal length measured by reconstructed MR image. Among them, the lateral decubitus position showed the strongest correlation with true renal length (right: 0.887; left: 0.849). We recommend measurement of the maximum renal longitudinal length in all possible positions on ultrasonography. If not allowed, the best measurement is on the lateral decubitus showing the strongest correlation coefficient with true renal length

  18. Comparative analysis of maximum renal longitudinal length with positional changes on ultrasound with multiplanar reconstructed MR image in Korea Adults

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Yun Hee; Cho, Bum Sang; Kang, Min Ho; Kang, Woo Young; Lee, Jisun; Kim, Yook; Lee, Soo Hyun; Lee, Soo Jung [Dept. of Radiology, Chungbuk National University Hospital, Cheongju (Korea, Republic of); Lee, Jin Yong [Public Health Medical Service, Seoul National University Boramae Medical Center, Seoul (Korea, Republic of)

    2016-07-15

    The purpose of this study was to determine a suitable position in which the measured length on ultrasound is close to the true renal length obtained through a multiplanar reconstructed MR image. A total of 33 individuals (males: 15, females: 18) without any underlying renal disease were included in the present study. Renal length was measured as the longest axis at the level of the renal hilum in three positions-supine, lateral decubitus, and prone, respectively. With a 3.0 T MR scanner, 3D eTHRIVE was acquired. Subsequently, the maximum longitudinal length of both the kidneys was measured through multiplanar reconstructed MR images. Paired t-test was used to compare the renal length obtained from ultrasonographic measurement with the length obtained through multiplanar reconstructed MR images. Our study demonstrated significant difference between sonographic renal length in three positions and renal length through MRI (p < 0.001). However, the longest longitudinal length of right kidney among the measured three values by ultrasound was statistically similar to the renal length measured by reconstructed MR image. Among them, the lateral decubitus position showed the strongest correlation with true renal length (right: 0.887; left: 0.849). We recommend measurement of the maximum renal longitudinal length in all possible positions on ultrasonography. If not allowed, the best measurement is on the lateral decubitus showing the strongest correlation coefficient with true renal length.

  19. Estimation of ocular volume from axial length.

    Science.gov (United States)

    Nagra, Manbir; Gilmartin, Bernard; Logan, Nicola S

    2014-12-01

    To determine which biometric parameters provide optimum predictive power for ocular volume. Sixty-seven adult subjects were scanned with a Siemens 3-T MRI scanner. Mean spherical error (MSE) (D) was measured with a Shin-Nippon autorefractor and a Zeiss IOLMaster used to measure (mm) axial length (AL), anterior chamber depth (ACD) and corneal radius (CR). Total ocular volume (TOV) was calculated from T2-weighted MRIs (voxel size 1.0 mm(3)) using an automatic voxel counting and shading algorithm. Each MR slice was subsequently edited manually in the axial, sagittal and coronal plane, the latter enabling location of the posterior pole of the crystalline lens and partitioning of TOV into anterior (AV) and posterior volume (PV) regions. Mean values (±SD) for MSE (D), AL (mm), ACD (mm) and CR (mm) were -2.62±3.83, 24.51±1.47, 3.55±0.34 and 7.75±0.28, respectively. Mean values (±SD) for TOV, AV and PV (mm(3)) were 8168.21±1141.86, 1099.40±139.24 and 7068.82±1134.05, respectively. TOV showed significant correlation with MSE, AL, PV (all p<0.001), CR (p=0.043) and ACD (p=0.024). Bar CR, the correlations were shown to be wholly attributable to variation in PV. Multiple linear regression indicated that the combination of AL and CR provided optimum R(2) values of 79.4% for TOV. Clinically useful estimations of ocular volume can be obtained from measurement of AL and CR. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  20. Midupper arm circumference and weight-for-length z scores have different associations with body composition

    DEFF Research Database (Denmark)

    Grijalva-Eternod, Carlos S; Wells, Jonathan Ck; Girma, Tsinuel

    2015-01-01

    understood. OBJECTIVE: We investigated the association between these 2 anthropometric indexes and body composition to help understand why they identify different children as wasted. DESIGN: We analyzed weight, length, MUAC, fat-mass (FM), and fat-free mass (FFM) data from 2470 measurements from 595 healthy...... Ethiopian infants obtained at birth and at 1.5, 2.5, 3.5, 4.5, and 6 mo of age. We derived WLZs by using 2006 WHO growth standards. We derived length-adjusted FM and FFM values as unexplained residuals after regressing each FM and FFM against length. We used a correlation analysis to assess associations...... between length, FFM, and FM (adjusted and nonadjusted for length) and the MUAC and WLZ and a multivariable regression analysis to assess the independent variability of length and length-adjusted FM and FFM with either the MUAC or the WLZ as the outcome. RESULTS: At all ages, length showed consistently...

  1. Speciation of Bactrocera dorsalis complex based on aedeagus length

    International Nuclear Information System (INIS)

    Osamu Iwahashi

    2000-01-01

    A species complex of Bactrocera dorsalis (Hendel) in Southeast Asia is composed of 52 species (Drew and Hancock, 1994) and while some of these species are economically very important, distinguishing them based on morphological characters has been difficult (White and Elson-Harris 1992). Specifically, there is considerable difficulty in differentiating between males of two pairs of sympatric species, B. philippinensis Drew and Hancock/B. occipitalis (Bezzi) in the Philippines and B. carambolae Drew and Hancock/B. papayae Drew and Hancock in Indonesia. This may be, in part, because the evolutionary processes within this species complex are still very dynamic, and that natural hybridisation between sympatric species pairs might be occurring on a regular basis (He and Haymer 1997). Iwaizumi et al. (1997) developed a simple method to differentiate the two sets of sympatric species based on aedeagus lengths. However, these flies had been reared artificially under laboratory conditions and only a small number of specimens (n=5) was used. Consequently, they were not able to obtain a frequency distribution of the aedeagus length for each species. Iwahashi (1998) measured a larger number of wild flies collected on Guimaras Is, Philippines, and found that flies with the aedeagus length of 2.89 mm are B. philippinensis. Iwahashi (1999) also showed that the measurement of the aedeagal length of fruit flies is a reliable characteristic for distinguishing between the 2 sympatric species pairs in the B. dorsalis complex. This being so, it may also be interesting to interpret phylogenetic relationships among B. dorsalis complex species based on the aedeagus length. Thus, aedeagus lengths of different populations of five B. dorsalis complex species are measured and their relationships discussed

  2. Length scale for configurational entropy in microemulsions

    NARCIS (Netherlands)

    Reiss, H.; Kegel, W.K.; Groenewold, J.

    1996-01-01

    In this paper we study the length scale that must be used in evaluating the mixing entropy in a microemulsion. The central idea involves the choice of a length scale in configuration space that is consistent with the physical definition of entropy in phase space. We show that this scale may be

  3. Proofs of Contracted Length Non-covariance

    International Nuclear Information System (INIS)

    Strel'tsov, V.N.

    1994-01-01

    Different proofs of contracted length non covariance are discussed. The way based on the establishment of interval inconstancy (dependence on velocity) seems to be the most convincing one. It is stressed that the known non covariance of the electromagnetic field energy and momentum of a moving charge ('the problem 4/3') is a direct consequence of contracted length non covariance. 8 refs

  4. Influence of mandibular length on mouth opening

    NARCIS (Netherlands)

    Dijkstra, PU; Hof, AL; Stegenga, B; De Bont, LGM

    Theoretically, mouth opening not only reflects the mobility of the temporomandibular joints (TMJs) but also the mandibular length. Clinically, the exact relationship between mouth opening, mandibular length, and mobility of TMJs is unclear. To study this relationship 91 healthy subjects, 59 women

  5. Test-retest reliability of spatial and temporal gait parameters in children with cerebral palsy as measured by an electronic walkway.

    Science.gov (United States)

    Sorsdahl, Anne Brit; Moe-Nilssen, Rolf; Strand, Liv Inger

    2008-01-01

    The purpose of this study was to examine test-retest reliability of seven selected temporal and spatial gait parameters and asymmetry measures in children with cerebral palsy. Seventeen children with CP between 3 and 13 years of age walked at three different speeds across an electronic walkway of 5.2m. The tests were repeated after approximately 25 min. The scores were normalized to a walking speed of 1.1m/s to avoid the confounding effect of gait speed on speed dependent gait parameters. Intraclass correlation coefficients (ICC(1,1) and ICC(3,1)) with 95% confidence intervals, within-subject standard deviation (S(w)) and smallest detectable difference (SDD) were calculated. The relative reliability of cadence, step length, stride length and single stance time was high to excellent (ICC(1,1) between 0.73 and 0.95), while it was poor for step width (ICC(1,1)=0.27 and 0.35). The relative reliability for two calculated asymmetry measures were high for the step length index (ICC(1,1)=0.82) and moderate for the single stance time index (ICC(1,1)=0.49). The absolute reliability values for all gait parameters are reported. Five of seven gait parameters measured by an electronic walkway and normalized to a common walking speed, appear to be highly repeatable in a short-term time span in children with CP who were able to walk without assistive walking devices, provided sufficient cognitive function.

  6. Screening length in dusty plasma crystals

    International Nuclear Information System (INIS)

    Nikolaev, V S; Timofeev, A V

    2016-01-01

    Particles interaction and value of the screening length in dusty plasma systems are of great interest in dusty plasma area. Three inter-particle potentials (Debye potential, Gurevich potential and interaction potential in the weakly collisional regime) are used to solve equilibrium equations for two dusty particles suspended in a parabolic trap. The inter-particle distance dependence on screening length, trap parameter and particle charge is obtained. The functional form of inter-particle distance dependence on ion temperature is investigated and compared with experimental data at 200-300 K in order to test used potentials applicability to dusty plasma systems at room temperatures. The preference is given to the Yukawa-type potential including effective values of particle charge and screening length. The estimated effective value of the screening length is 5-15 times larger than the Debye length. (paper)

  7. Reducing Length of Stay in Total Joint Arthroplasty Care.

    Science.gov (United States)

    Walters, Megan; Chambers, Monique C; Sayeed, Zain; Anoushiravani, Afshin A; El-Othmani, Mouhanad M; Saleh, Khaled J

    2016-10-01

    As health care reforms continue to improve quality of care, significant emphasis will be placed on evaluation of orthopedic patient outcomes. Total joint arthroplasty (TJA) has a proven track record of enhancing patient quality of life and are easily replicable. The outcomes of these procedures serve as a measure of health care initiative success. Specifically, length of stay, will be targeted as a marker of quality of surgical care delivered to TJA patients. Within this review, we will discuss preoperative and postoperative methods by which orthopedic surgeons may enhance TJA outcomes and effectively reduce length of stay. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Determination of thermal neutrons diffusion length in graphite

    International Nuclear Information System (INIS)

    Garcia Fite, J.

    1959-01-01

    The diffusion length of thermal neutrons in graphite using the less possible quantity of material has been determined. The proceeding used was the measurement in a graphite pile which has a punctual source of rapid neutrons inside surrounded by a reflector medium (paraffin or water). The measurement was done in the following conditions: a) introducing an aluminium plate between both materials. b) Introducing a cadmium plate between both materials. (Author) 91 refs

  9. Assessing Telomere Length Using Surface Enhanced Raman Scattering

    Science.gov (United States)

    Zong, Shenfei; Wang, Zhuyuan; Chen, Hui; Cui, Yiping

    2014-11-01

    Telomere length can provide valuable insight into telomeres and telomerase related diseases, including cancer. Here, we present a brand-new optical telomere length measurement protocol using surface enhanced Raman scattering (SERS). In this protocol, two single strand DNA are used as SERS probes. They are labeled with two different Raman molecules and can specifically hybridize with telomeres and centromere, respectively. First, genome DNA is extracted from cells. Then the telomere and centromere SERS probes are added into the genome DNA. After hybridization with genome DNA, excess SERS probes are removed by magnetic capturing nanoparticles. Finally, the genome DNA with SERS probes attached is dropped onto a SERS substrate and subjected to SERS measurement. Longer telomeres result in more attached telomere probes, thus a stronger SERS signal. Consequently, SERS signal can be used as an indicator of telomere length. Centromere is used as the inner control. By calibrating the SERS intensity of telomere probe with that of the centromere probe, SERS based telomere measurement is realized. This protocol does not require polymerase chain reaction (PCR) or electrophoresis procedures, which greatly simplifies the detection process. We anticipate that this easy-operation and cost-effective protocol is a fine alternative for the assessment of telomere length.

  10. Modelling length of hospital stay in motor victims

    Directory of Open Access Journals (Sweden)

    Mercedes Ayuso-Gutiérrez

    2015-03-01

    Full Text Available Objective. To analyze which socio-demographic and other factors related to motor injuries affect the length of hospital recovery stay. Materials and methods. In the study a sample of 17 932 motor accidents was used. All the crashes occurred in Spain between 2000 and 2007. Different regression models were fitted to data to identify and measure the impact of a set of explanatory regressors. Results. Time of hospital stay for men is on average 41% larger than for women. When the victim has a fracture as a consequence of the accident, the mean time of hospital stay is multiplied by five. Injuries located in lower extremities, the head and abdomen are associated with greater hospitalization lengths. Conclusions. Gender, age and type of victim, as well as the location and nature of injuries, are found to be factors that have significant impact on the expected length of hospital stay.

  11. Zero-point length from string fluctuations

    International Nuclear Information System (INIS)

    Fontanini, Michele; Spallucci, Euro; Padmanabhan, T.

    2006-01-01

    One of the leading candidates for quantum gravity, viz. string theory, has the following features incorporated in it. (i) The full spacetime is higher-dimensional, with (possibly) compact extra-dimensions; (ii) there is a natural minimal length below which the concept of continuum spacetime needs to be modified by some deeper concept. On the other hand, the existence of a minimal length (zero-point length) in four-dimensional spacetime, with obvious implications as UV regulator, has been often conjectured as a natural aftermath of any correct quantum theory of gravity. We show that one can incorporate the apparently unrelated pieces of information-zero-point length, extra-dimensions, string T-duality-in a consistent framework. This is done in terms of a modified Kaluza-Klein theory that interpolates between (high-energy) string theory and (low-energy) quantum field theory. In this model, the zero-point length in four dimensions is a 'virtual memory' of the length scale of compact extra-dimensions. Such a scale turns out to be determined by T-duality inherited from the underlying fundamental string theory. From a low energy perspective short distance infinities are cutoff by a minimal length which is proportional to the square root of the string slope, i.e., α ' . Thus, we bridge the gap between the string theory domain and the low energy arena of point-particle quantum field theory

  12. The telomere length dynamic and methods of its assessment.

    Science.gov (United States)

    Lin, Kah-Wai; Yan, Ju

    2005-01-01

    Human telomeres are composed of long repeating sequences of TTAGGG, associated with a variety of telomere-binding proteins. Its function as an end-protector of chromosomes prevents the chromosome from end-to-end fusion, recombination and degradation. Telomerase acts as reverse transcriptase in the elongation of telomeres, which prevent the loss of telomeres due to the end replication problems. However, telomerase activity is detected at low level in somatic cells and high level in embryonic stem cells and tumor cells. It confers immortality to embryonic stem cells and tumor cells. In most tumor cells, telomeres are extremely short and stable. Telomere length is an important indicator of the telomerase activity in tumor cells and it may be used in the prognosis of malignancy. Thus, the assessment of telomeres length is of great experimental and clinical significance. This review describes the role of telomere and telomerase in cancer pathogenesis and the dynamics of the telomeres length in different cell types. The various methods of measurement of telomeres length, i.e. southern blot, hybridization protection assay, fluorescence in situ hybridization, primed in situ, quantitative PCR and single telomere length analysis are discussed. The principle and comparative evaluation of these methods are reviewed. The detection of G-strand overhang by telomeric-oligonucleotide ligation assay, primer extension/nick translation assay and electron microscopy are briefly discussed.

  13. The length dependence of the series elasticity of pig bladder smooth muscle

    NARCIS (Netherlands)

    R. van Mastrigt (Ron)

    1988-01-01

    textabstractStrips of urinary bladder smooth muscle were subjected to a series of quick release measurements. Each measurement consisted of several releases and resets to the original length, made during one contraction. The complete length-force characteristic of series elasticity was quantified by

  14. Coherent Smith-Purcell radiation as a diagnostic for sub-picosecond electron bunch length

    International Nuclear Information System (INIS)

    Nguyen, D.C.

    1996-01-01

    We suggest a novel technique of measuring sub-picosecond electron bunch length base on coherent Smith-Purcell radiation (SPR) emitted when electrons pass close to the surface of a metal grating. With electron bunch lengths comparable to the grating period, we predict that coherent SPR will be emitted at large angles with respect to direction of beam propagation. As the bunch length shortens, the coherent SPR will be enhanced over the incoherent component that is normally observed at small angles. Furthermore, the angular distribution of the coherent SPR will be shifted toward smaller angles as the bunch length becomes much smaller than the grating period. By measuring the angular distribution of the coherent SPR, one can determine the bunch length of sub-picosecond electron pulses. This new technique is easy to implement and appears capable of measuring femtosecond electron bunch lengths

  15. Allometric relationships among body mass, MUZZLE-tail length, and tibia length during the growth of Wistar rats.

    Science.gov (United States)

    Santiago, Hildemberg Agostinho Rocha de; De Pierro, Lucas Rodolfo; Reis, Rafael Menezes; Caluz, Antônio Gabriel Ricardo Engracia; Ribeiro, Victor Barbosa; Volpon, José Batista

    2015-11-01

    To investigate allometric relationships among body mass (BM), muzzle-tail length (MTL), and tibia length (TL) in Wistar rats and establish their growth rate change parameters. Eighteen male and 18 female Wistar rats were studied from the 3rd to the 21st week of age. BM, MTL, and TL were measured daily, and relative growth was compared using allometry. A positive correlation between BM and MTL (p<0.05) and BM and TL (p<0.05) was observed. Males and females showed comparable curves; however, females had turning points at a younger age. The allometric relationship between BM and MTL presented a regular increase until reaching a mass of 351 g (males) and 405 g (females). BM and TL showed an initial increase until 185 g (males) and 182 g (females), and then reached a plateau that finished at 412 g (males) and 334 g (females), to display another increase. The allometric relationship of body mass with animal length and tibia length was comparable for male and female rats, with female rats maturing earlier. Animal longitudinal growth occurred in a single stage. In contrast, tibia length depicted two stages of accelerated growth with an intermediate period of deceleration.

  16. The benefits of longer fuel cycle lengths

    International Nuclear Information System (INIS)

    Kesler, D.C.

    1986-01-01

    Longer fuel cycle lengths have been found to increase generation and improve outage management. A study at Duke Power Company has shown that longer fuel cycles offer both increased scheduling flexibility and increased capacity factors

  17. Atomic frequency-time-length standards

    International Nuclear Information System (INIS)

    Gheorghiu, O.C.; Mandache, C.

    1987-01-01

    The principles of operative of atomic frequency-time-length standards and their principle characteristics are described. The role of quartz crystal oscillators which are sloved to active or passive standards is presented. (authors)

  18. Complementary DNA-amplified fragment length polymorphism ...

    African Journals Online (AJOL)

    Complementary DNA-amplified fragment length polymorphism (AFLP-cDNA) analysis of differential gene expression from the xerophyte Ammopiptanthus mongolicus in response to cold, drought and cold together with drought.

  19. Impedance of finite length resistive cylinder

    Directory of Open Access Journals (Sweden)

    S. Krinsky

    2004-11-01

    Full Text Available We determine the impedance of a cylindrical metal tube (resistor of radius a, length g, and conductivity σ attached at each end to perfect conductors of semi-infinite length. Our main interest is in the asymptotic behavior of the impedance at high frequency (k≫1/a. In the equilibrium regime, ka^{2}≪g, the impedance per unit length is accurately described by the well-known result for an infinite length tube with conductivity σ. In the transient regime, ka^{2}≫g, where the contribution of transition radiation arising from the discontinuity in conductivity is important, we derive an analytic expression for the impedance and compute the short-range wakefield. The analytic results are shown to agree with numerical evaluation of the impedance.

  20. Characteristic length of the knotting probability revisited

    International Nuclear Information System (INIS)

    Uehara, Erica; Deguchi, Tetsuo

    2015-01-01

    We present a self-avoiding polygon (SAP) model for circular DNA in which the radius of impermeable cylindrical segments corresponds to the screening length of double-stranded DNA surrounded by counter ions. For the model we evaluate the probability for a generated SAP with N segments having a given knot K through simulation. We call it the knotting probability of a knot K with N segments for the SAP model. We show that when N is large the most significant factor in the knotting probability is given by the exponentially decaying part exp(−N/N K ), where the estimates of parameter N K are consistent with the same value for all the different knots we investigated. We thus call it the characteristic length of the knotting probability. We give formulae expressing the characteristic length as a function of the cylindrical radius r ex , i.e. the screening length of double-stranded DNA. (paper)

  1. Chord length distribution for a compound capsule

    International Nuclear Information System (INIS)

    Pitřík, Pavel

    2017-01-01

    Chord length distribution is a factor important in the calculation of ionisation chamber responses. This article describes Monte Carlo calculations of the chord length distribution for a non-convex compound capsule. A Monte Carlo code was set up for generation of random chords and calculation of their lengths based on the input number of generations and cavity dimensions. The code was written in JavaScript and can be executed in the majority of HTML viewers. The plot of occurrence of cords of different lengths has 3 peaks. It was found that the compound capsule cavity cannot be simply replaced with a spherical cavity of a triangular design. Furthermore, the compound capsule cavity is directionally dependent, which must be taken into account in calculations involving non-isotropic fields of primary particles in the beam, unless equilibrium of the secondary charged particles is attained. (orig.)

  2. Study on the Connecting Length of CFRP

    Science.gov (United States)

    Liu, Xiongfei; Li, Yue; Li, Zhanguo

    2018-05-01

    The paper studied the varying mode of shear stress in the connecting zone of CFRP. Using epoxy resin (EP) as bond material, performance of specimens with different connecting length of CFRP was tested to obtain the conclusion. CFRP-confined concrete column was tested subsequently to verify the conclusion. The results show that: (1) The binding properties of modified epoxy resin with CFRP is good; (2) As the connecting length increased, the ultimate tensile strength of CFRP increased as well in the range of the experiment parameters; (3) Tensile strength of CFRP can reach the ultimate strength when the connecting length is 90mm;(4) The connecting length of 90mm of CFRP meet the reinforcement requirements.

  3. Fragment Length of Circulating Tumor DNA.

    Science.gov (United States)

    Underhill, Hunter R; Kitzman, Jacob O; Hellwig, Sabine; Welker, Noah C; Daza, Riza; Baker, Daniel N; Gligorich, Keith M; Rostomily, Robert C; Bronner, Mary P; Shendure, Jay

    2016-07-01

    Malignant tumors shed DNA into the circulation. The transient half-life of circulating tumor DNA (ctDNA) may afford the opportunity to diagnose, monitor recurrence, and evaluate response to therapy solely through a non-invasive blood draw. However, detecting ctDNA against the normally occurring background of cell-free DNA derived from healthy cells has proven challenging, particularly in non-metastatic solid tumors. In this study, distinct differences in fragment length size between ctDNAs and normal cell-free DNA are defined. Human ctDNA in rat plasma derived from human glioblastoma multiforme stem-like cells in the rat brain and human hepatocellular carcinoma in the rat flank were found to have a shorter principal fragment length than the background rat cell-free DNA (134-144 bp vs. 167 bp, respectively). Subsequently, a similar shift in the fragment length of ctDNA in humans with melanoma and lung cancer was identified compared to healthy controls. Comparison of fragment lengths from cell-free DNA between a melanoma patient and healthy controls found that the BRAF V600E mutant allele occurred more commonly at a shorter fragment length than the fragment length of the wild-type allele (132-145 bp vs. 165 bp, respectively). Moreover, size-selecting for shorter cell-free DNA fragment lengths substantially increased the EGFR T790M mutant allele frequency in human lung cancer. These findings provide compelling evidence that experimental or bioinformatic isolation of a specific subset of fragment lengths from cell-free DNA may improve detection of ctDNA.

  4. Electron Effective-Attenuation-Length Database

    Science.gov (United States)

    SRD 82 NIST Electron Effective-Attenuation-Length Database (PC database, no charge)   This database provides values of electron effective attenuation lengths (EALs) in solid elements and compounds at selected electron energies between 50 eV and 2,000 eV. The database was designed mainly to provide EALs (to account for effects of elastic-eletron scattering) for applications in surface analysis by Auger-electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS).

  5. Length and coverage of inhibitory decision rules

    KAUST Repository

    Alsolami, Fawaz

    2012-01-01

    Authors present algorithms for optimization of inhibitory rules relative to the length and coverage. Inhibitory rules have a relation "attribute ≠ value" on the right-hand side. The considered algorithms are based on extensions of dynamic programming. Paper contains also comparison of length and coverage of inhibitory rules constructed by a greedy algorithm and by the dynamic programming algorithm. © 2012 Springer-Verlag.

  6. The SME gauge sector with minimum length

    Energy Technology Data Exchange (ETDEWEB)

    Belich, H.; Louzada, H.L.C. [Universidade Federal do Espirito Santo, Departamento de Fisica e Quimica, Vitoria, ES (Brazil)

    2017-12-15

    We study the gauge sector of the Standard Model Extension (SME) with the Lorentz covariant deformed Heisenberg algebra associated to the minimum length. In order to find and estimate corrections, we clarify whether the violation of Lorentz symmetry and the existence of a minimum length are independent phenomena or are, in some way, related. With this goal, we analyze the dispersion relations of this theory. (orig.)

  7. The SME gauge sector with minimum length

    Science.gov (United States)

    Belich, H.; Louzada, H. L. C.

    2017-12-01

    We study the gauge sector of the Standard Model Extension (SME) with the Lorentz covariant deformed Heisenberg algebra associated to the minimum length. In order to find and estimate corrections, we clarify whether the violation of Lorentz symmetry and the existence of a minimum length are independent phenomena or are, in some way, related. With this goal, we analyze the dispersion relations of this theory.

  8. Progress in Long Scale Length Laser-Plasma Interactions

    International Nuclear Information System (INIS)

    Glenzer, S H; Arnold, P; Bardsley, G; Berger, R L; Bonanno, G; Borger, T; Bower, D E; Bowers, M; Bryant, R; Buckman, S.; Burkhart, S C; Campbell, K; Chrisp, M P; Cohen, B I; Constantin, G; Cooper, F; Cox, J; Dewald, E; Divol, L; Dixit, S; Duncan, J; Eder, D; Edwards, J; Erbert, G; Felker, B; Fornes, J; Frieders, G; Froula, D H; Gardner, S D; Gates, C; Gonzalez, M; Grace, S; Gregori, G; Greenwood, A; Griffith, R; Hall, T; Hammel, B A; Haynam, C; Heestand, G; Henesian, M; Hermes, G; Hinkel, D; Holder, J; Holdner, F; Holtmeier, G; Hsing, W; Huber, S; James, T; Johnson, S; Jones, O S; Kalantar, D; Kamperschroer, J H; Kauffman, R; Kelleher, T; Knight, J; Kirkwood, R K; Kruer, W L; Labiak, W; Landen, O L; Langdon, A B; Langer, S; Latray, D; Lee, A; Lee, F D; Lund, D; MacGowan, B; Marshall, S; McBride, J; McCarville, T; McGrew, L; Mackinnon, A J; Mahavandi, S; Manes, K; Marshall, C; Mertens, E; Meezan, N; Miller, G; Montelongo, S; Moody, J D; Moses, E; Munro, D; Murray, J; Neumann, J; Newton, M; Ng, E; Niemann, C; Nikitin, A; Opsahl, P; Padilla, E; Parham, T; Parrish, G; Petty, C; Polk, M; Powell, C; Reinbachs, I; Rekow, V; Rinnert, R; Riordan, B; Rhodes, M.

    2003-01-01

    The first experiments on the National Ignition Facility (NIF) have employed the first four beams to measure propagation and laser backscattering losses in large ignition-size plasmas. Gas-filled targets between 2 mm and 7 mm length have been heated from one side by overlapping the focal spots of the four beams from one quad operated at 351 nm (3ω) with a total intensity of 2 x 10 15 W cm -2 . The targets were filled with 1 atm of CO 2 producing of up to 7 mm long homogeneously heated plasmas with densities of n e = 6 x 10 20 cm -3 and temperatures of T e = 2 keV. The high energy in a NIF quad of beams of 16kJ, illuminating the target from one direction, creates unique conditions for the study of laser plasma interactions at scale lengths not previously accessible. The propagation through the large-scale plasma was measured with a gated x-ray imager that was filtered for 3.5 keV x rays. These data indicate that the beams interact with the full length of this ignition-scale plasma during the last ∼1 ns of the experiment. During that time, the full aperture measurements of the stimulated Brillouin scattering and stimulated Raman scattering show scattering into the four focusing lenses of 6% for the smallest length (∼2 mm). increasing to 12% for ∼7 mm. These results demonstrate the NIF experimental capabilities and further provide a benchmark for three-dimensional modeling of the laser-plasma interactions at ignition-size scale lengths

  9. Cervical Length in Patients at Risk for Placenta Accreta.

    Science.gov (United States)

    Rac, Martha W F; McIntire, Donald D; Wells, C Edward; Moschos, Elysia; Twickler, Diane D

    2017-07-01

    To evaluate cervical length measurements in women with placenta accreta compared to women with a nonadherent low-lying placenta or placenta previa and evaluate this relationship in terms of vaginal bleeding, preterm labor, and preterm birth. We conducted a retrospective cohort study between 1997 and 2011 of gravidas with more than 1 prior cesarean delivery who had a transvaginal ultrasound examination between 24 and 34 weeks for a low-lying placenta or placenta previa. Cervical length was measured from archived images in accordance with national guidelines by a single investigator, who was blinded to outcomes and ultrasound reports. The diagnosis of placental accreta was based on histologic confirmation. For study purposes, preterm birth was defined as less than 36 weeks, and cervical lengths of 3 cm or less were considered short. Standard statistical analyses were used. A total of 125 patients met inclusion criteria. The cohort was divided into patients with (n = 43 [34%]) and without (n = 82 [66%]) placenta accreta and stratified by gestational age at the ultrasound examinations. Women with placenta accreta had shorter cervical length measurements during their 32- to 34-week ultrasound examinations (mean ± SD, 3.23 ± 0.98 versus 3.95 ± 1.0 cm; P accreta had shorter cervical lengths at 32 to 34 weeks than women with a nonadherent low-lying placenta or placenta previa, but this finding did not correlate with a higher risk of vaginal bleeding or preterm labor resulting in preterm birth before 36 weeks. © 2017 by the American Institute of Ultrasound in Medicine.

  10. Relation of Stump Length with Various Gait Parameters in Trans-tibial Amputee

    Directory of Open Access Journals (Sweden)

    Koyel Majumdar

    2008-07-01

    Full Text Available The purpose of this paper is evaluating the impact of stump length of unilateral below knee amputees (BKA on different gait parameters. Nine unilateral BKA were chosen and divided into three groups comprising patients with short, medium, and long stump length. Each of them underwent gait analysis test by Computer Dynography (CDG system to measure the gait parameters. It was found that the ground reaction force is higher in the patients with medium stump length whereas the velocity, step length both for the prosthetic and sound limb and cadence were high in longer stump length. Statistical analysis shows a significant difference (p<0.05 between the gait parameters of BKA with medium and longer stump length. The patients with longer stump length were more efficient than medium and short stump patients as they consumed comparatively lesser energy while walking with self-selected velocity and conventional (Solid ankle cushioned heel SACH foot.

  11. Ratio-based lengths of intervals to improve fuzzy time series forecasting.

    Science.gov (United States)

    Huarng, Kunhuang; Yu, Tiffany Hui-Kuang

    2006-04-01

    The objective of this study is to explore ways of determining the useful lengths of intervals in fuzzy time series. It is suggested that ratios, instead of equal lengths of intervals, can more properly represent the intervals among observations. Ratio-based lengths of intervals are, therefore, proposed to improve fuzzy time series forecasting. Algebraic growth data, such as enrollments and the stock index, and exponential growth data, such as inventory demand, are chosen as the forecasting targets, before forecasting based on the various lengths of intervals is performed. Furthermore, sensitivity analyses are also carried out for various percentiles. The ratio-based lengths of intervals are found to outperform the effective lengths of intervals, as well as the arbitrary ones in regard to the different statistical measures. The empirical analysis suggests that the ratio-based lengths of intervals can also be used to improve fuzzy time series forecasting.

  12. A STUDY OF CORRELATION OF FOOT LENGTH AND GESTATIONAL MATURITY IN NEONATES

    Directory of Open Access Journals (Sweden)

    M. Bhuvaneswari

    2018-03-01

    Full Text Available BACKGROUND Gestational age estimation at birth can be done by clinical estimation through careful history of LMP, ultrasonic estimation of gestational age, date of first recorded foetal activity “quickening” first felt at approximately 16-18 weeks, Date of first recorded foetal heart sounds. MATERIALS AND METHODS A study sample of 800 live newborns were selected by simple random sampling technique born at GVR hospital and Government General Hospital, Kurnool from April 2015 to May 2016. Data was collected using standard proforma meeting the objectives of the study. a Gestational age assessment was done using modified Bellard’s score and b Foot length was measured using sliding calipers which is having an accuracy of a millimeter. Following instruments are used: 1 Sliding calipers for measuring foot length, 2 Flexible, non-stretchable measuring tape for head circumference, 3 Infantometer for measuring crown heel length, 4 Electronic weighing scale for measuring weight. RESULTS The foot length of preterm neonates ranged from 4.5-7.8 cm with the mean foot length of 6.1571 cm and 6.6964 cm for preterm SGA and AGA, respectively. The foot length of term neonates ranged from 5.4-8.7 cm with a mean foot length of 7.0471 cm, 7.5703 cm, 8.0391 cm for term SGA, AGA, LGA respectively. The foot length for post term neonates ranged from 6.7-8.8 cm, with a mean foot length of 7.5688 cm, 8.0170 cm and 8.2667 cm for post term SGA, AGA and LGA, respectively. This shows that foot length increases as the gestational age increases. CONCLUSION Foot length can be correlated significantly with the gestational age, birth weight, head circumference and crown heel length.

  13. Childhood adversity, social support, and telomere length among perinatal women.

    Science.gov (United States)

    Mitchell, Amanda M; Kowalsky, Jennifer M; Epel, Elissa S; Lin, Jue; Christian, Lisa M

    2018-01-01

    Adverse perinatal health outcomes are heightened among women with psychosocial risk factors, including childhood adversity and a lack of social support. Biological aging could be one pathway by which such outcomes occur. However, data examining links between psychosocial factors and indicators of biological aging among perinatal women are limited. The current study examined the associations of childhood socioeconomic status (SES), childhood trauma, and current social support with telomere length in peripheral blood mononuclear cells (PBMCs) in a sample of 81 women assessed in early, mid, and late pregnancy as well as 7-11 weeks postpartum. Childhood SES was defined as perceived childhood social class and parental educational attainment. Measures included the Childhood Trauma Questionnaire, Center for Epidemiologic Studies-Depression Scale, Multidimensional Scale of Perceived Social Support, and average telomere length in PBMCs. Per a linear mixed model, telomere length did not change across pregnancy and postpartum visits; thus, subsequent analyses defined telomere length as the average across all available timepoints. ANCOVAs showed group differences by perceived childhood social class, maternal and paternal educational attainment, and current family social support, with lower values corresponding with shorter telomeres, after adjustment for possible confounds. No effects of childhood trauma or social support from significant others or friends on telomere length were observed. Findings demonstrate that while current SES was not related to telomeres, low childhood SES, independent of current SES, and low family social support were distinct risk factors for cellular aging in women. These data have relevance for understanding potential mechanisms by which early life deprivation of socioeconomic and relationship resources affect maternal health. In turn, this has potential significance for intergenerational transmission of telomere length. The predictive value of

  14. Association of Telomere Length with Breast Cancer Prognostic Factors.

    Directory of Open Access Journals (Sweden)

    Kaoutar Ennour-Idrissi

    Full Text Available Telomere length, a marker of cell aging, seems to be affected by the same factors thought to be associated with breast cancer prognosis.To examine associations of peripheral blood cell-measured telomere length with traditional and potential prognostic factors in breast cancer patients.We conducted a cross-sectional analysis of data collected before surgery from 162 breast cancer patients recruited consecutively between 01/2011 and 05/2012, at a breast cancer reference center. Data on the main lifestyle factors (smoking, alcohol consumption, physical activity were collected using standardized questionnaires. Anthropometric factors were measured. Tumor biological characteristics were extracted from pathology reports. Telomere length was measured using a highly reproducible quantitative PCR method in peripheral white blood cells. Spearman partial rank-order correlations and multivariate general linear models were used to evaluate relationships between telomere length and prognostic factors.Telomere length was positively associated with total physical activity (rs = 0.17, P = 0.033; Ptrend = 0.069, occupational physical activity (rs = 0.15, P = 0.054; Ptrend = 0.054 and transportation-related physical activity (rs = 0.19, P = 0.019; P = 0.005. Among post-menopausal women, telomere length remained positively associated with total physical activity (rs = 0.27, P = 0.016; Ptrend = 0.054 and occupational physical activity (rs = 0.26, P = 0.021; Ptrend = 0.056 and was only associated with transportation-related physical activity among pre-menopausal women (rs = 0.27, P = 0.015; P = 0.004. No association was observed between telomere length and recreational or household activities, other lifestyle factors or traditional prognostic factors.Telomeres are longer in more active breast cancer patients. Since white blood cells are involved in anticancer immune responses, these findings suggest that even regular low-intensity physical activity, such as that

  15. Time-dependent evolution of strand transfer length in pretensioned prestressed concrete members

    Science.gov (United States)

    Caro, L. A.; Martí-Vargas, J. R.; Serna, P.

    2013-11-01

    For design purposes, it is generally considered that prestressing strand transfer length does not change with time. However, some experimental studies on the effect of time on transfer lengths show contradictory results. In this paper, an experimental research to study transfer length changes over time is presented. A test procedure based on the ECADA testing technique to measure prestressing strand force variation over time in pretensioned prestressed concrete specimens has been set up. With this test method, an experimental program that varies concrete strength, specimen cross section, age of release, prestress transfer method, and embedment length has been carried out. Both the initial and long-term transfer lengths of 13-mm prestressing steel strands have been measured. The test results show that transfer length variation exists for some prestressing load conditions, resulting in increased transfer length over time. The applied test method based on prestressing strand force measurements has shown more reliable results than procedures based on measuring free end slips and longitudinal strains of concrete. An additional factor for transfer length models is proposed in order to include the time-dependent evolution of strand transfer length in pretensioned prestressed concrete members.

  16. length-weight relationhip of freshwater wild fish species

    African Journals Online (AJOL)

    Dr Naeem

    2012-06-21

    Jun 21, 2012 ... Length-weight (LWR) and length-length relationships (LLR) were determined for a freshwater catfish ... Key words: Mystus bleekeri, length-weight relationship, length-length relationship, predictive equations. INTRODUCTION. Mystus bleekeri (freshwater catfish Day, 1877), locally ..... fish farmers, Aquacult.

  17. Length dependence of force generation exhibit similarities between rat cardiac myocytes and skeletal muscle fibres.

    Science.gov (United States)

    Hanft, Laurin M; McDonald, Kerry S

    2010-08-01

    According to the Frank-Starling relationship, increased ventricular volume increases cardiac output, which helps match cardiac output to peripheral circulatory demand. The cellular basis for this relationship is in large part the myofilament length-tension relationship. Length-tension relationships in maximally calcium activated preparations are relatively shallow and similar between cardiac myocytes and skeletal muscle fibres. During twitch activations length-tension relationships become steeper in both cardiac and skeletal muscle; however, it remains unclear whether length dependence of tension differs between striated muscle cell types during submaximal activations. The purpose of this study was to compare sarcomere length-tension relationships and the sarcomere length dependence of force development between rat skinned left ventricular cardiac myocytes and fast-twitch and slow-twitch skeletal muscle fibres. Muscle cell preparations were calcium activated to yield 50% maximal force, after which isometric force and rate constants (k(tr)) of force development were measured over a range of sarcomere lengths. Myofilament length-tension relationships were considerably steeper in fast-twitch fibres compared to slow-twitch fibres. Interestingly, cardiac myocyte preparations exhibited two populations of length-tension relationships, one steeper than fast-twitch fibres and the other similar to slow-twitch fibres. Moreover, myocytes with shallow length-tension relationships were converted to steeper length-tension relationships by protein kinase A (PKA)-induced myofilament phosphorylation. Sarcomere length-k(tr) relationships were distinct between all three cell types and exhibited patterns markedly different from Ca(2+) activation-dependent k(tr) relationships. Overall, these findings indicate cardiac myocytes exhibit varied length-tension relationships and sarcomere length appears a dominant modulator of force development rates. Importantly, cardiac myocyte length

  18. Determination of the paraxial focal length using Zernike polynomials over different apertures

    Science.gov (United States)

    Binkele, Tobias; Hilbig, David; Henning, Thomas; Fleischmann, Friedrich

    2017-02-01

    The paraxial focal length is still the most important parameter in the design of a lens. As presented at the SPIE Optics + Photonics 2016, the measured focal length is a function of the aperture. The paraxial focal length can be found when the aperture approaches zero. In this work, we investigate the dependency of the Zernike polynomials on the aperture size with respect to 3D space. By this, conventional wavefront measurement systems that apply Zernike polynomial fitting (e.g. Shack-Hartmann-Sensor) can be used to determine the paraxial focal length, too. Since the Zernike polynomials are orthogonal over a unit circle, the aperture used in the measurement has to be normalized. By shrinking the aperture and keeping up with the normalization, the Zernike coefficients change. The relation between these changes and the paraxial focal length are investigated. The dependency of the focal length on the aperture size is derived analytically and evaluated by simulation and measurement of a strong focusing lens. The measurements are performed using experimental ray tracing and a Shack-Hartmann-Sensor. Using experimental ray tracing for the measurements, the aperture can be chosen easily. Regarding the measurements with the Shack-Hartmann- Sensor, the aperture size is fixed. Thus, the Zernike polynomials have to be adapted to use different aperture sizes by the proposed method. By doing this, the paraxial focal length can be determined from the measurements in both cases.

  19. Explaining the length threshold of polyglutamine aggregation

    International Nuclear Information System (INIS)

    De Los Rios, Paolo; Hafner, Marc; Pastore, Annalisa

    2012-01-01

    The existence of a length threshold, of about 35 residues, above which polyglutamine repeats can give rise to aggregation and to pathologies, is one of the hallmarks of polyglutamine neurodegenerative diseases such as Huntington’s disease. The reason why such a minimal length exists at all has remained one of the main open issues in research on the molecular origins of such classes of diseases. Following the seminal proposals of Perutz, most research has focused on the hunt for a special structure, attainable only above the minimal length, able to trigger aggregation. Such a structure has remained elusive and there is growing evidence that it might not exist at all. Here we review some basic polymer and statistical physics facts and show that the existence of a threshold is compatible with the modulation that the repeat length imposes on the association and dissociation rates of polyglutamine polypeptides to and from oligomers. In particular, their dramatically different functional dependence on the length rationalizes the very presence of a threshold and hints at the cellular processes that might be at play, in vivo, to prevent aggregation and the consequent onset of the disease. (paper)

  20. Explaining the length threshold of polyglutamine aggregation

    Science.gov (United States)

    De Los Rios, Paolo; Hafner, Marc; Pastore, Annalisa

    2012-06-01

    The existence of a length threshold, of about 35 residues, above which polyglutamine repeats can give rise to aggregation and to pathologies, is one of the hallmarks of polyglutamine neurodegenerative diseases such as Huntington’s disease. The reason why such a minimal length exists at all has remained one of the main open issues in research on the molecular origins of such classes of diseases. Following the seminal proposals of Perutz, most research has focused on the hunt for a special structure, attainable only above the minimal length, able to trigger aggregation. Such a structure has remained elusive and there is growing evidence that it might not exist at all. Here we review some basic polymer and statistical physics facts and show that the existence of a threshold is compatible with the modulation that the repeat length imposes on the association and dissociation rates of polyglutamine polypeptides to and from oligomers. In particular, their dramatically different functional dependence on the length rationalizes the very presence of a threshold and hints at the cellular processes that might be at play, in vivo, to prevent aggregation and the consequent onset of the disease.