Breaking the Myth That Relay Swimming Is Faster Than Individual Swimming.
Skorski, Sabrina; Etxebarria, Naroa; Thompson, Kevin G
2016-04-01
To investigate if swimming performance is better in a relay race than in the corresponding individual race. The authors analyzed 166 elite male swimmers from 15 nations in the same competition (downloaded from www.swimrankings.net). Of 778 observed races, 144 were Olympic Games performances (2000, 2004, 2012), with the remaining 634 performed in national or international competitions. The races were 100-m (n = 436) and 200-m (n = 342) freestyle events. Relay performance times for the 2nd-4th swimmers were adjusted (+ 0.73 s) to allow for the "flying start." Without any adjustment, mean individual relay performances were significantly faster for the first 50 m and overall time in the 100-m events. Furthermore, the first 100 m of the 200-m relay was significantly faster (P > .001). During relays, swimmers competing in 1st position did not show any difference compared with their corresponding individual performance (P > .16). However, swimmers competing in 2nd-4th relay-team positions demonstrated significantly faster times in the 100-m (P < .001) and first half of the 200-m relays than in their individual events (P < .001, ES: 0.28-1.77). However, when finishing times for 2nd-4th relay team positions were adjusted for the flying start no differences were detected between relay and individual race performance for any event or split time (P > .17). Highly trained swimmers do not swim (or turn) faster in relay events than in their individual races. Relay exchange times account for the difference observed in individual vs relay performance.
Schapschröer, M; Baker, J; Schorer, J
2016-08-01
In the context of perceptual-cognitive expertise it is important to know whether physiological loads influence perceptual-cognitive performance. This study examined whether a handball specific physical exercise load influenced participants' speed and accuracy in a flicker task. At rest and during a specific interval exercise of 86.5-90% HRmax, 35 participants (experts: n=8, advanced: n=13, novices, n=14) performed a handball specific flicker task with two types of patterns (structured and unstructured). For reaction time, results revealed moderate effect sizes for group, with experts reacting faster than advanced and advanced reacting faster than novices, and for structure, with structured videos being performed faster than unstructured ones. A significant interaction for structure×group was also found, with experts and advanced players faster for structured videos, and novices faster for unstructured videos. For accuracy, significant main effects were found for structure with structured videos solved more accurately. A significant interaction for structure×group was revealed, with experts and advanced more accurate for structured scenes and novices more accurate for unstructured scenes. A significant interaction was also found for condition×structure; at rest, unstructured and structured scenes were performed with the same accuracy while under physical exercise, structured scenes were solved more accurately. No other interactions were found. These results were somewhat surprising given previous work in this area, although the impact of a specific physical exercise on a specific perceptual-cognitive task may be different from those tested generally. Copyright © 2016 Elsevier B.V. All rights reserved.
Mechanical Determinants of Faster Change of Direction Speed Performance in Male Athletes.
DosʼSantos, Thomas; Thomas, Christopher; Jones, Paul A; Comfort, Paul
2017-03-01
Dos'Santos, T, Thomas, C, Jones, PA, and Comfort, P. Mechanical determinants of faster change of direction speed performance in male athletes. J Strength Cond Res 31(3): 696-705, 2017-Mechanical variables during change of directions, for example, braking and propulsive forces, impulses, and ground contact times (GCT) have been identified as determinants of faster change of direction speed (CODS) performance. The purpose of this study was to investigate the mechanical determinants of 180° CODS performance with mechanical characteristic comparisons between faster and slower performers; while exploring the role of the penultimate foot contact (PEN) during the change of direction. Forty multidirectional male athletes performed 6 modified 505 (mod505) trials (3 left and right), and ground reaction forces were collected across the PEN and final foot contact (FINAL) during the change of direction. Pearson's correlation coefficients and coefficients of determination were used to explore the relationship between mechanical variables and mod505 completion time. Independent T-tests and Cohen's d effect sizes (ES) were conducted between faster (n = 10) and slower (n = 10) mod505 performers to explore differences in mechanical variables. Faster CODS performance was associated (p ≤ 0.05) with shorter GCTs (r = 0.701-0.757), greater horizontal propulsive forces (HPF) (r = -0.572 to -0.611), greater horizontal braking forces (HBF) in the PEN (r = -0.337), lower HBF ratios (r = -0.429), and lower FINAL vertical impact forces (VIF) (r = 0.449-0.559). Faster athletes demonstrated significantly (p ≤ 0.05, ES = 1.08-2.54) shorter FINAL GCTs, produced lower VIF, lower HBF ratios, and greater HPF in comparison to slower athletes. These findings suggest that different mechanical properties are required to produce faster CODS performance, with differences in mechanical properties observed between fast and slower performers. Furthermore, applying a greater proportion of braking force during the PEN relative to the FINAL may be advantageous for turning performance.
ERIC Educational Resources Information Center
Forbes, Bethany E.; Skinner, Christopher H.; Maurer, Kristin; Taylor, Emily; Schall, Megan; Cazzell, Samantha; Ciancio, Dennis; Conley, Matt; Conley, Elisha
2015-01-01
Working with middle-school students, we replicated and extended research on oral reading fluency (ORF) assessments and prompting students to read faster. Altering ORF administration procedures by instructing students to read fast caused statistically significant increases in their words correct per minute (WCPM) and errors, which was moderated by…
Chung, Tae Nyoung; Kim, Sun Wook; You, Je Sung; Chung, Hyun Soo
2016-01-01
Objective Tube thoracostomy (TT) is a commonly performed intensive care procedure. Simulator training may be a good alternative method for TT training, compared with conventional methods such as apprenticeship and animal skills laboratory. However, there is insufficient evidence supporting use of a simulator. The aim of this study is to determine whether training with medical simulator is associated with faster TT process, compared to conventional training without simulator. Methods This is a simulation study. Eligible participants were emergency medicine residents with very few (≤3 times) TT experience. Participants were randomized to two groups: the conventional training group, and the simulator training group. While the simulator training group used the simulator to train TT, the conventional training group watched the instructor performing TT on a cadaver. After training, all participants performed a TT on a cadaver. The performance quality was measured as correct placement and time delay. Subjects were graded if they had difficulty on process. Results Estimated median procedure time was 228 seconds in the conventional training group and 75 seconds in the simulator training group, with statistical significance (P=0.040). The difficulty grading did not show any significant difference among groups (overall performance scale, 2 vs. 3; P=0.094). Conclusion Tube thoracostomy training with a medical simulator, when compared to no simulator training, is associated with a significantly faster procedure, when performed on a human cadaver. PMID:27752610
How gender and task difficulty affect a sport-protective response in young adults
Lipps, David B.; Eckner, James T.; Richardson, James K.; Ashton-Miller, James A.
2013-01-01
We tested the hypotheses that gender and task difficulty affect the reaction, movement, and total response times associated with performing a head protective response. Twenty-four healthy young adults (13 females) performed a protective response of raising their hands from waist level to block a foam ball fired at their head from an air cannon. Participants initially stood 8.25 m away from the cannon (‘low difficulty’), and were moved successively closer in 60 cm increments until they failed to block at least 5 of 8 balls (‘high difficulty’). Limb motion was quantified using optoelectronic markers on the participants’ left wrist. Males had significantly faster total response times (p = 0.042), a trend towards faster movement times (p = 0.054), and faster peak wrist velocity (p < .001) and acceleration (p = 0.032) than females. Reaction time, movement time, and total response time were significantly faster under high difficulty conditions for both genders (p < .001). This study suggests that baseball and softball pitchers and fielders should have sufficient time to protect their head from a batted ball under optimal conditions if they are adequately prepared for the task. PMID:23234296
Causer, Joe; Harvey, Adrian; Snelgrove, Ryan; Arsenault, Gina; Vickers, Joan N
2014-08-01
We examined the effectiveness of technical training (TT) and quiet eye training (QE) on the performance of one-handed square knot tying in surgical residents. Twenty surgical residents were randomly assigned to the 2 groups and completed pretest, training, retention, and transfer tests. Participants wore a mobile eye tracker that simultaneously recorded their gaze and hand movements. Dependent variables were knot tying performance (%), QE duration (%), number of fixations, total movement time (s), and hand movement phase time (s). The QE training group had significantly higher performance scores, a longer QE duration, fewer fixations, faster total knot tying times, and faster movement phase times compared with the TT group. The QE group maintained performance in the transfer test, whereas the TT group significantly decreased performance from retention to transfer. QE training significantly improved learning, retention, and transfer of surgical knot tying compared with a traditional technical approach. Both performance effectiveness (performance outcome) and movement efficiency (hand movement times) were improved using QE modeling, instruction, and feedback. Copyright © 2014 Elsevier Inc. All rights reserved.
Do Right- and Left-Handed Monkeys Differ on Cognitive Measures?
NASA Technical Reports Server (NTRS)
Hopkins, William D.; Washburn, David A.
1994-01-01
Twelve left- and 14 right-handed monkeys were compared on 6 measures of cognitive performance (2 maze-solving tasks, matching-to-sample, delayed matching-to-sample, delayed response using spatial cues, and delayed response using form cues). The dependent variable was trials-to-training criterion for each of the 6 tasks. Significant differences were found between left- and right-handed monkeys on the 2 versions of the delayed response task. Right-handed monkeys reached criterion significantly faster on the form cue version of the task, whereas left-handed monkeys reached criterion significantly faster on delayed response for spatial position (p less than .05). The results suggest that sensitive hand preference measures of laterality can reveal differences in cognitive performance, which in turn may reflect underlying laterality in functional organization of the nervous system.
Display format, highlight validity, and highlight method: Their effects on search performance
NASA Technical Reports Server (NTRS)
Donner, Kimberly A.; Mckay, Tim D.; Obrien, Kevin M.; Rudisill, Marianne
1991-01-01
Display format and highlight validity were shown to affect visual display search performance; however, these studies were conducted on small, artificial displays of alphanumeric stimuli. A study manipulating these variables was conducted using realistic, complex Space Shuttle information displays. A 2x2x3 within-subjects analysis of variance found that search times were faster for items in reformatted displays than for current displays. Responses to valid applications of highlight were significantly faster than responses to non or invalidly highlighted applications. The significant format by highlight validity interaction showed that there was little difference in response time to both current and reformatted displays when the highlight validity was applied; however, under the non or invalid highlight conditions, search times were faster with reformatted displays. A separate within-subject analysis of variance of display format, highlight validity, and several highlight methods did not reveal a main effect of highlight method. In addition, observed display search times were compared to search time predicted by Tullis' Display Analysis Program. Benefits of highlighting and reformatting displays to enhance search and the necessity to consider highlight validity and format characteristics in tandem for predicting search performance are discussed.
Priming effects for affective vs. neutral faces.
Burton, Leslie A; Rabin, Laura; Wyatt, Gwinne; Frohlich, Jonathan; Bernstein Vardy, Susan; Dimitri, Diana
2005-12-01
Affective and Neutral Tasks (faces with negative or neutral content, with different lighting and orientation) requiring reaction time judgments of poser identity were administered to 32 participants. Speed and accuracy were better for the Affective than Neutral Task, consistent with literature suggesting facilitation of performance by affective content. Priming effects were significant for the Affective but not Neutral Task. An Explicit Post-Test indicated no conscious knowledge of the stimulus frequency that was associated with performance facilitation. Faster performance by female vs. male participants, and differential speeds and susceptibility to priming of different emotions were also found. Anger and shock were responded to most rapidly and accurately in several conditions, showed no gender differences, and showed significant priming for both RT and accuracy. Fear and pain were responded to least accurately, were associated with faster female than male reaction time, and the accuracy data showed a kind of reverse priming.
The effect of video game "warm-up" on performance of laparoscopic surgery tasks.
Rosser, James C; Gentile, Douglas A; Hanigan, Kevin; Danner, Omar K
2012-01-01
Performing laparoscopic procedures requires special training and has been documented as a significant source of surgical errors. "Warming up" before performing a task has been shown to enhance performance. This study investigates whether surgeons benefit from "warming up" using select video games immediately before performing laparoscopic partial tasks and clinical tasks. This study included 303 surgeons (249 men and 54 women). Participants were split into a control (n=180) and an experimental group (n=123). The experimental group played 3 previously validated video games for 6 minutes before task sessions. The Cobra Rope partial task and suturing exercises were performed immediately after the warm-up sessions. Surgeons who played video games prior to the Cobra Rope drill were significantly faster on their first attempt and across all 10 trials. The experimental and control groups were significantly different in their total suturing scores (t=2.28, df=288, P<.05). The overall Top Gun score showed that the experimental group performed marginally better overall. This study demonstrates that subjects completing "warming-up" sessions with select video games prior to performing laparoscopic partial and clinical tasks (intracorporeal suturing) were faster and had fewer errors than participants not engaging in "warm-up." More study is needed to determine whether this translates into superior procedural execution in the clinical setting.
Effects of Different Lifting Cadences on Ground Reaction Forces during the Squat Exercise
NASA Technical Reports Server (NTRS)
Bentley, Jason R.; Amonette, William E.; Hagan, R. Donald
2008-01-01
The purpose of this investigation was to determine the effect of different cadences on the ground reaction force (GRF(sub R)) during the squat exercise. It is known that squats performed with greater acceleration will produce greater inertial forces; however, it is not well understood how different squat cadences affect GRF(sub R). It was hypothesized that faster squat cadences will result in greater peak GRF(sub R). METHODS: Six male subjects (30.8+/-4.4 y, 179.5+/-8.9 cm, 88.8+/-13.3 kg) with previous squat experience performed three sets of three squats using three different cadences (FC = 1 sec descent/1 sec ascent; MC = 3 sec descent/1 sec ascent; SC = 4 sec descent/2 sec ascent) with barbell mass equal to body mass. Ground reaction force was used to calculate inertial force trajectories of the body plus barbell (FI(sub system)). Forces were normalized to body mass. RESULTS: Peak GRF(sub R) and peak FI(sub system) were significantly higher in FC squats compared to MC (p=0.0002) and SC (p=0.0002). Range of GRF(sub R) and FI(sub system) were also significantly higher in FC compared to MC (p<0.05), and MC were significantly higher than SC (p<0.05). DISCUSSION: Faster squat cadences result in significantly greater peak GRF(sub R) due to the inertia of the system. GRF(sub R) was more dependent upon decent cadence than on ascent cadence. PRACTICAL APPLICATION: This study demonstrates that faster squat cadences produce greater ground reaction forces. Therefore, the use of faster squat cadences might enhance strength and power adaptations to long-term resistance exercise training. Key Words: velocity, weight training, resistive exercise
ERIC Educational Resources Information Center
de Jonge, Maretha V.; Kemner, Chantal; van Engeland, Herman
2006-01-01
We assessed the disembedding performance on the Embedded Figures Test (EFT) of high-functioning subjects with autism or autism spectrum disorders from multi-incidence families and the performance of their parents. The individuals with autism spectrum disorders were significantly faster than matched controls in locating the shape, but their parents…
Ferris, Abbie E; Christiansen, Cory L; Heise, Gary D; Hahn, David; Smith, Jeremy D
2017-05-01
People with transtibial amputation stand ~50times/day. There are two general approaches to transtibial amputation: 1) distal tibia and fibula union using a "bone-bridge" (Ertl), 2) non-union of the tibia and fibula (Non-Ertl). The Ertl technique may improve functional outcomes by increasing the end-bearing ability of the residual limb. We hypothesized individuals with an Ertl would perform a five-time sit-to-stand task faster through greater involvement/end-bearing of the affected limb. Ertl (n=11) and Non-Ertl (n=7) participants sat on a chair with each foot on separate force plates and performed the five-time sit-to-stand task. A symmetry index (intact vs affected limbs) was calculated using peak ground reaction forces. The Ertl group performed the task significantly faster (9.33s (2.66) vs 13.27 (2.83)s). Symmetry index (23.33 (23.83)% Ertl, 36.53 (13.51)% Non-Ertl) indicated the intact limb for both groups produced more force than the affected limb. Ertl affected limb peak ground reaction forces were significantly larger than the Non-Ertl affected limb. Peak knee power and net work of the affected limb were smaller than their respective intact limb for both groups. The Ertl intact limb produced significantly greater peak knee power and net work than the Non-Ertl intact knee. Although loading asymmetries existed between the intact and affected limb of both groups, the Ertl group performed the task ~30% faster. This was driven by greater power and work production of the Ertl intact limb knee. Our results suggest that functional differences exist between the procedures. Copyright © 2017 Elsevier Ltd. All rights reserved.
Deconstructing Planning Ability in Children and Adolescents with Anorexia Nervosa.
Rose, Mark; Reville, Marie-Claire; Iszatt, Amber; Levinson, Simon; Frampton, Ian; Lask, Bryan
2017-01-01
Weaknesses in planning by patients with anorexia nervosa (AN) have been noted (e.g., Zakzanis, Campbell, & Polsinelli, 2010 ) and are generally based on adults. This study explored D-KEFS Tower Test performance to better understand learning styles and strategies used by child and adolescent patients with AN compared to healthy controls. Overall, no significant differences were found in achievement; however, Item 5 predicted performance across harder items. The AN group was significantly faster to move their first disc suggesting patients with AN did not spend as much time planning their strategies for item completion. The findings of this study in conjunction with other studies investigating planning in AN may suggest the existence of subtle differences in learning style and strategy, such as faster initiation times, rather than gross planning differences. Further research is required to better understand the relationship between these subtle differences and clinical presentations.
Performance characterization of image and video analysis systems at Siemens Corporate Research
NASA Astrophysics Data System (ADS)
Ramesh, Visvanathan; Jolly, Marie-Pierre; Greiffenhagen, Michael
2000-06-01
There has been a significant increase in commercial products using imaging analysis techniques to solve real-world problems in diverse fields such as manufacturing, medical imaging, document analysis, transportation and public security, etc. This has been accelerated by various factors: more advanced algorithms, the availability of cheaper sensors, and faster processors. While algorithms continue to improve in performance, a major stumbling block in translating improvements in algorithms to faster deployment of image analysis systems is the lack of characterization of limits of algorithms and how they affect total system performance. The research community has realized the need for performance analysis and there have been significant efforts in the last few years to remedy the situation. Our efforts at SCR have been on statistical modeling and characterization of modules and systems. The emphasis is on both white-box and black box methodologies to evaluate and optimize vision systems. In the first part of this paper we review the literature on performance characterization and then provide an overview of the status of research in performance characterization of image and video understanding systems. The second part of the paper is on performance evaluation of medical image segmentation algorithms. Finally, we highlight some research issues in performance analysis in medical imaging systems.
Schill, Matthew R.; Varela, J. Esteban; Frisella, Margaret M.; Brunt, L. Michael
2015-01-01
Background We compared performance of validated laparoscopic tasks on four commercially available single site access (SSA) access devices (AD) versus an independent port (IP) SSA set-up. Methods A prospective, randomized comparison of laparoscopic skills performance on four AD (GelPOINT™, SILS™ Port, SSL Access System™, TriPort™) and one IP SSA set-up was conducted. Eighteen medical students (2nd–4th year), four surgical residents, and five attending surgeons were trained to proficiency in multi-port laparoscopy using four laparoscopic drills (peg transfer, bean drop, pattern cutting, extracorporeal suturing) in a laparoscopic trainer box. Drills were then performed in random order on each IP-SSA and AD-SSA set-up using straight laparoscopic instruments. Repetitions were timed and errors recorded. Data are mean ± SD, and statistical analysis was by two-way ANOVA with Tukey HSD post-hoc tests. Results Attending surgeons had significantly faster total task times than residents or students (p< 0.001), but the difference between residents and students was NS. Pair-wise comparisons revealed significantly faster total task times for the IP-SSA set-up compared to all four AD-SSA’s within the student group only (p<0.05). Total task times for residents and attending surgeons showed a similar profile, but the differences were NS. When data for the three groups was combined, the total task time was less for the IP-SSA set-up than for each of the four AD-SSA set-ups (p < 0.001). Similarly,, the IP-SSA set-up was significantly faster than 3 of 4 AD-SSA set-ups for peg transfer, 3 of 4 for pattern cutting, and 2 of 4 for suturing. No significant differences in error rates between IP-SSA and AD-SSA set-ups were detected. Conclusions When compared to an IP-SSA laparoscopic set-up, single site access devices are associated with longer task performance times in a trainer box model, independent of level of training. Task performance was similar across different SSA devices. PMID:21993938
Batting cage performance of wood and nonwood youth baseball bats.
Crisco, Joseph J; Rainbow, Michael J; Schwartz, Joel B; Wilcox, Bethany J
2014-04-01
The purpose of this study was to examine the batting cage performance of wood and nonwood baseball bats used at the youth level. Three wood and ten nonwood bats were swung by 22 male players (13 to 18 years old) in a batting cage equipped with a 3-dimensional motion capture (300 Hz) system. Batted ball speeds were compared using a one-way ANOVA and bat swing speeds were analyzed as a function of bat moment of inertia by linear regression. Batted ball speeds were significantly faster for three nonwood bat models (P<.001), significantly slower for one nonwood model, and not different for six nonwood bats when compared with wood bats. Bat impact speed significantly (P<.05) decreased with increasing bat moment of inertia for the 13-, 14-, and 15-year-old groups, but not for the other age groups. Ball-bat coefficients of restitution (BBCOR) for all nonwood were greater than for wood, but this factor alone did not correlate with bat performance. Our findings indicate that increases in BBCOR and swing speed were not associated with faster batted ball speeds for the bats studied whose moment of inertia was substantially less than that of a wood bat of similar length.
An enhanced high-speed multi-digit BCD adder using quantum-dot cellular automata
NASA Astrophysics Data System (ADS)
Ajitha, D.; Ramanaiah, K. V.; Sumalatha, V.
2017-02-01
The advent of development of high-performance, low-power digital circuits is achieved by a suitable emerging nanodevice called quantum-dot cellular automata (QCA). Even though many efficient arithmetic circuits were designed using QCA, there is still a challenge to implement high-speed circuits in an optimized manner. Among these circuits, one of the essential structures is a parallel multi-digit decimal adder unit with significant speed which is very attractive for future environments. To achieve high speed, a new correction logic formulation method is proposed for single and multi-digit BCD adder. The proposed enhanced single-digit BCD adder (ESDBA) is 26% faster than the carry flow adder (CFA)-based BCD adder. The multi-digit operations are also performed using the proposed ESDBA, which is cascaded innovatively. The enhanced multi-digit BCD adder (EMDBA) performs two 4-digit and two 8-digit BCD addition 50% faster than the CFA-based BCD adder with the nominal overhead of the area. The EMDBA performs two 4-digit BCD addition 24% faster with 23% decrease in the area, similarly for 8-digit operation the EMDBA achieves 36% increase in speed with 21% less area compared to the existing carry look ahead (CLA)-based BCD adder design. The proposed multi-digit adder produces significantly less delay of (N –1) + 3.5 clock cycles compared to the N* One digit BCD adder delay required by the conventional BCD adder method. It is observed that as per our knowledge this is the first innovative proposal for multi-digit BCD addition using QCA.
Ten Haaf, Twan; van Staveren, Selma; Iannetta, Danilo; Roelands, Bart; Meeusen, Romain; Piacentini, Maria F; Foster, Carl; Koenderman, Leo; Daanen, Hein A M; de Koning, Jos J
2018-04-01
Reaction time has been proposed as a training monitoring tool, but to date, results are equivocal. Therefore, it was investigated whether reaction time can be used as a monitoring tool to establish overreaching. The study included 30 subjects (11 females and 19 males, age: 40.8 [10.8] years, VO 2max : 51.8 [6.3] mL/kg/min) who participated in an 8-day cycling event. The external exercise load increased approximately 900% compared with the preparation period. Performance was measured before and after the event using a maximal incremental cycling test. Subjects with decreased performance after the event were classified as functionally overreached (FOR) and others as acutely fatigued (AF). A choice reaction time test was performed 2 weeks before (pre), 1 week after (post), and 5 weeks after (follow-up), as well as at the start and end of the event. A total of 14 subjects were classified as AF and 14 as FOR (2 subjects were excluded). During the event, reaction time at the end was 68 ms (95% confidence interval, 46-89) faster than at the start. Reaction time post event was 41 ms (95% confidence interval, 12-71) faster than pre event and follow-up was 55 ms faster (95% confidence interval, 26-83). The time by class interaction was not significant during (P = .26) and after (P = .43) the event. Correlations between physical performance and reaction time were not significant (all Ps > .30). No differences in choice reaction time between AF and FOR subjects were observed. It is suggested that choice reaction time is not valid for early detection of overreaching in the field.
Maloney, Sean J; Turner, Anthony N; Miller, Stuart
2014-10-01
It has previously been shown that a loaded warm-up may improve power performances. We examined the acute effects of loaded dynamic warm-up on change of direction speed (CODS), which had not been previously investigated. Eight elite badminton players participated in three sessions during which they performed vertical countermovement jump and CODS tests before and after undertaking the dynamic warm-up. The three warm-up conditions involved wearing a weighted vest (a) equivalent to 5% body mass, (b) equivalent to 10% body mass, and (c) a control where a weighted vest was not worn. Vertical jump and CODS performances were then tested at 15 seconds and 2, 4, and 6 minutes post warm-up. Vertical jump and CODS significantly improved following all warm-up conditions (P < .05). Post warm-up vertical jump performance was not different between conditions (P = .430). Post warm-up CODS was significantly faster following the 5% (P = .02) and 10% (P < .001) loaded conditions compared with the control condition. In addition, peak CODS test performances, independent of recovery time, were faster than the control condition following the 10% loaded condition (P = .012). In conclusion, the current study demonstrates that a loaded warm-up augmented CODS, but not vertical jump performance, in elite badminton players.
Laterality of repetitive finger movement performance and clinical features of Parkinson's disease.
Stegemöller, Elizabeth; Zaman, Andrew; MacKinnon, Colum D; Tillman, Mark D; Hass, Chris J; Okun, Michael S
2016-10-01
Impairments in acoustically cued repetitive finger movement often emerge at rates near to and above 2Hz in persons with Parkinson's Disease (PD) in which some patients move faster (hastening) and others move slower (bradykinetic). The clinical features impacting this differential performance of repetitive finger movement remain unknown. The purpose of this study was to compare repetitive finger movement performance between the more and less affected side, and the difference in clinical ratings among performance groups. Forty-one participants diagnosed with idiopathic PD completed an acoustically cued repetitive finger movement task while "on" medication. Eighteen participants moved faster, 10 moved slower, and 13 were able to maintain the appropriate rate at rates above 2Hz. Clinical measures of laterality, disease severity, and the UPDRS were obtained. There were no significant differences between the more and less affected sides regardless of performance group. Comparison of disease severity, tremor, and rigidity among performance groups revealed no significant differences. Comparison of posture and postural instability scores revealed that the participants that demonstrated hastening had worse posture and postural instability scores. Consideration of movement rate during the clinical evaluation of repetitive finger movement may provide additional insight into varying disease features in persons with PD. Copyright © 2016 Elsevier B.V. All rights reserved.
Fujibayashi, Nobuaki; Otsuka, Mitsuo; Yoshioka, Shinsuke; Isaka, Tadao
2017-10-24
The present study aims to cross-sectionally clarify the characteristics of the motions of an inverted pendulum model, a stance leg, a swing leg and arms in different triple-jumping techniques to understand whether or not hop displacement is relatively longer rather than step and jump displacements. Eighteen male athletes performed the triple jump with a full run-up. Based on the technique of the jumpers, they were classified as hop-dominated (n = 10) or balance (n = 8) jumpers. The kinematic data were calculated using motion capture and compared between the two techniques using the inverted pendulum model. The hop-dominated jumpers had a significantly longer hop displacement and faster vertical centre-of-mass (COM) velocity of their whole body at hop take-off, which was generated by faster rotation behaviours of inverted pendulum model and faster swinging behaviours of arms. Conversely, balance jumpers had a significantly longer jump displacement and faster horizontal COM velocity of their whole body at take-off, which was generated by a stiffer inverted pendulum model and stance leg. The results demonstrate that hop-dominated and balance jumpers enhanced each dominated-jump displacement using different swing- and stance-leg motions. This information may help to enhance the actual displacement of triple jumpers using different jumping techniques.
Shaikhouni, Ammar
2017-01-01
Converging evidence suggests that reinstatement of neural activity underlies our ability to successfully retrieve memories. However, the temporal dynamics of reinstatement in the human cortex remain poorly understood. One possibility is that neural activity during memory retrieval, like replay of spiking neurons in the hippocampus, occurs at a faster timescale than during encoding. We tested this hypothesis in 34 participants who performed a verbal episodic memory task while we recorded high gamma (62–100 Hz) activity from subdural electrodes implanted for seizure monitoring. We show that reinstatement of distributed patterns of high gamma activity occurs faster than during encoding. Using a time-warping algorithm, we quantify the timescale of the reinstatement and identify brain regions that show significant timescale differences between encoding and retrieval. Our data suggest that temporally compressed reinstatement of cortical activity is a feature of cued memory retrieval. SIGNIFICANCE STATEMENT We show that cued memory retrieval reinstates neural activity on a faster timescale than was present during encoding. Our data therefore provide a link between reinstatement of neural activity in the cortex and spontaneous replay of cortical and hippocampal spiking activity, which also exhibits temporal compression, and suggest that temporal compression may be a universal feature of memory retrieval. PMID:28336569
Effect of gender on fatigue and recovery following maximal intensity repeated sprint performance.
Laurent, C M; Green, J M; Bishop, P A; Sjökvist, J; Schumacker, R E; Richardson, M T; Curtner-Smith, M
2010-09-01
This study investigated the effects of gender on repeated, maximal-intensity intermittent sprint exercise following variable day-to-day recovery periods. Sixteen volunteers (8 men, 8 women) performed four trials of high-intensity intermittent sprint exercise consisting of three bouts of eight 30 m sprints (total of 24 sprints). Following completion of the baseline trial, in repeated-measures design, participants were assigned, in counter-balanced order, variable recovery periods of 24, 48, and 72 h whereupon they repeated an identical exercise trial. Results from a series of 4 (trial) x 3 (bout) repeated measures ANOVAs revealed men produced significantly (P < 0.01) faster times throughout all bouts and trials of repeated sprint exercise. Additionally, women exhibited significantly lower (P < 0.05) blood lactate concentration and significantly lower (P < 0.05) decrement in performance, indicating increased resistance to fatigue during repeated exercise sessions. There were no significant differences (P > 0.05) between genders for heart rate or rating of perceived exertion during or following trials. There were no significant differences for overall sprint performance within either gender among trials. These results indicate men, while able to produce higher absolute power outputs (i.e., lower sprint time), demonstrate higher decrement scores within a trial compared to women, thus suggesting women may recover faster and fatigue less. Also, gender differences affecting recovery within in a trial were observed to be diminished between trials (i.e., day-to-day recovery) of maximal intermittent sprint work evidenced by the observed stability of performance between trials following various recovery durations.
Effect of Abiotic Factors on Degradation of Imidacloprid.
Mahapatra, Bibhab; Adak, Totan; Patil, Naveen K B; Pandi, G Guru P; Gowda, G Basana; Yadav, Manoj Kumar; Mohapatra, S D; Rath, P C; Munda, Sushmita; Jena, Mayabini
2017-10-01
The role of soil moisture, light and pH on imidacloprid dissipation was investigated. A high performance liquid chromatography (HPLC) based method was developed to quantify imidacloprid present in soil with a recovery of more than 82%. Rate of dissipation of imidacloprid from soil was faster in submerged condition compared to field capacity and air dried condition. Imidacloprid dissipated non-significantly between sterile and non-sterile soils, but at field capacity, the dissipation was faster in non-sterile soil compared to sterile soil after 60 days of incubation. Similarly, under submergence, the dissipation of imidacloprid was 66.2% and 79.8% of the initial in sterile and non-sterile soils, respectively. Imidacloprid was rather stable in acidic and neutral water but was prone to photo-degradation. Therefore, imidacloprid degradation will be faster under direct sunlight and at higher soil moisture.
Skilled memory in expert figure skaters.
Deakin, J M; Allard, F
1991-01-01
The present studies extend skilled-memory theory to a domain involving the performance of motor sequences. Skilled figure skaters were better able than their less skilled counterparts to perform short skating sequences that were choreographed, rather than randomly constructed. Expert skaters encoded sequences for performance very differently from the way in which they encoded sequences that were verbally presented for verbal recall. Tasks interpolated between sequence and recall showed no significant influence on recall accuracy, implicating long-term memory in skating memory. There was little evidence for the use of retrieval structures when skaters learned the brief sequences used throughout these studies. Finally, expert skaters were able to judge the similarity of two skating elements faster than less skilled skaters, indicating a faster access to semantic memory for experts. The data indicate that skaters show many of the same skilled-memory characteristics as have been described in other skill domains involving memorization, such as digit span and memory for dinner orders.
Factors affecting computer mouse use for young children: implications for AAC.
Costigan, F Aileen; Light, Janice C; Newell, Karl M
2012-06-01
More than 12% of preschoolers receiving special education services have complex communication needs, including increasing numbers of children who do not have significant motor impairments (e.g., children with autism spectrum disorders, Down syndrome, etc.). In order to meet their diverse communication needs (e.g., face-to-face, written, Internet, telecommunication), these children may use mainstream technologies accessed via the mouse, yet little is known about factors that affect the mouse performance of young children. This study used a mixed factorial design to investigate the effects of age, target size, and angle of approach on accuracy and time required for accurate target selection with a mouse for 20 3-year-old and 20 4-year-old children. The 4-year-olds were generally more accurate and faster than the 3-year-olds. Target size and angle mediated differences in performance within age groups. The 3-year-olds were more accurate and faster in selecting the medium and large targets relative to the small target, were faster in selecting the large relative to the medium target, and were faster in selecting targets along the vertical relative to the diagonal angle. The 4-year-olds were faster in selecting the medium and large targets relative to the small target. Implications for improving access to AAC include the preliminary suggestion of age-related threshold target sizes that support sufficient accuracy, the possibility of efficiency benefits when target size is increased up to an age-related threshold, and identification of the potential utility of the vertical angle as a context for training navigational input device use.
Is Single-Port Laparoscopy More Precise and Faster with the Robot?
Fransen, Sofie A F; van den Bos, Jacqueline; Stassen, Laurents P S; Bouvy, Nicole D
2016-11-01
Single-port laparoscopy is a step forward toward nearly scar less surgery. Concern has been raised that single-incision laparoscopic surgery (SILS) is technically more challenging because of the lack of triangulation and the clashing of instruments. Robotic single-incision laparoscopic surgery (RSILS) in chopstick setting might overcome these problems. This study evaluated the outcome in time and errors of two tasks of the Fundamentals of Laparoscopic Surgery on a dry platform, in two settings: SILS versus RSILS. Nine experienced laparoscopic surgeons performed two tasks: peg transfer and a suturing task, on a standard box trainer. All participants practiced each task three times in both settings: SILS and a RSILS setting. The assessment scores (time and errors) were recorded. For the first task of peg transfer, RSILS was significantly better in time (124 versus 230 seconds, P = .0004) and errors (0.80 errors versus 2.60 errors, P = .024) at the first run, compared to the SILS setting. At the third and final run, RSILS still proved to be significantly better in errors (0.10 errors versus 0.80 errors, P = .025) compared to the SILS group. RSILS was faster in the third run, but not significant (116 versus 157 seconds, P = .08). For the second task, a suturing task, only 3 participants of the SILS group were able to perform this task within the set time frame of 600 seconds. There was no significant difference in time in the three runs between SILS and RSILS for the 3 participants that fulfilled both tasks within the 600 seconds. This study shows that robotic single-port surgery seems easier, faster, and more precise to perform basis tasks of the Fundamentals of laparoscopic surgery. For the more complex task of suturing, only the single-port robotic setting enabled all participants to fulfill this task, within the set time frame.
Poltavski, Dmitri; Biberdorf, David
2015-01-01
Abstract In the growing field of sports vision little is still known about unique attributes of visual processing in ice hockey and what role visual processing plays in the overall athlete's performance. In the present study we evaluated whether visual, perceptual and cognitive/motor variables collected using the Nike SPARQ Sensory Training Station have significant relevance to the real game statistics of 38 Division I collegiate male and female hockey players. The results demonstrated that 69% of variance in the goals made by forwards in 2011-2013 could be predicted by their faster reaction time to a visual stimulus, better visual memory, better visual discrimination and a faster ability to shift focus between near and far objects. Approximately 33% of variance in game points was significantly related to better discrimination among competing visual stimuli. In addition, reaction time to a visual stimulus as well as stereoptic quickness significantly accounted for 24% of variance in the mean duration of the player's penalty time. This is one of the first studies to show that some of the visual skills that state-of-the-art generalised sports vision programmes are purported to target may indeed be important for hockey players' actual performance on the ice.
Muiños, Mónica; Ballesteros, Soledad
2014-11-01
The present study investigated peripheral vision (PV) and perceptual asymmetries in young and older martial arts athletes (judo and karate athletes) and compared their performance with that of young and older nonathletes. Stimuli were dots presented at three different eccentricities along the horizontal, oblique, and vertical diameters and three interstimulus intervals. Experiment 1 showed that although the two athlete groups were faster in almost all conditions, karate athletes performed significantly better than nonathlete participants when stimuli were presented in the peripheral visual field. Experiment 2 showed that older participants who had practiced a martial art at a competitive level when they were young were significantly faster than sedentary older adults of the same age. The practiced sport (judo or karate) did not affect performance differentially, suggesting that it is the practice of martial arts that is the crucial factor, rather than the type of martial art. Importantly, older athletes lose their PV advantage, as compared with young athletes. Finally, we found that physical activity (young and older athletes) and age (young and older adults) did not alter the visual asymmetries that vary as a function of spatial location; all participants were faster for stimuli presented along the horizontal than for those presented along the vertical meridian and for those presented at the lower rather than at the upper locations within the vertical meridian. These results indicate that the practice of these martial arts is an effective way of counteracting the processing speed decline of visual stimuli appearing at any visual location and speed.
Peak, J N; Turner, K M; Burne, T H J
2015-01-01
Developmental vitamin D (DVD) deficiency is a plausible risk factor for schizophrenia that has been associated with behavioural alterations including disruptions in latent inhibition and response inhibition. The rodent gambling task (rGT) assesses risk-based decision-making, which is a key cognitive deficit observed in schizophrenia patients. The primary aim of this study was to examine risk-based decision-making in DVD-deficient and control rats on the rGT. We also evaluated the performance of female Sprague-Dawley rats on the rGT for the first time. Adult male and female Sprague-Dawley rats from control and vitamin D deficient dams were trained to perform the rGT in standard operant chambers and their performance and choice-preferences were assessed. Female rats were significantly faster to reach rGT training criteria compared with male rats and DVD-deficient rats were faster to reach training criteria than control animals. After reaching stable performance on the rGT DVD-deficient and control rats showed a significant preference for the optimal choice-option in the rGT, but there were no significant effects of sex or diet on these responses. DVD deficiency did not alter the decision-making processes on the rGT because no significant changes in choice-preferences were evident. This is the first study to demonstrate that once established, the performance of females is comparable to male Sprague-Dawley rats on the rGT. Crown Copyright © 2014. Published by Elsevier Inc. All rights reserved.
Yaffe, Robert B; Shaikhouni, Ammar; Arai, Jennifer; Inati, Sara K; Zaghloul, Kareem A
2017-04-26
Converging evidence suggests that reinstatement of neural activity underlies our ability to successfully retrieve memories. However, the temporal dynamics of reinstatement in the human cortex remain poorly understood. One possibility is that neural activity during memory retrieval, like replay of spiking neurons in the hippocampus, occurs at a faster timescale than during encoding. We tested this hypothesis in 34 participants who performed a verbal episodic memory task while we recorded high gamma (62-100 Hz) activity from subdural electrodes implanted for seizure monitoring. We show that reinstatement of distributed patterns of high gamma activity occurs faster than during encoding. Using a time-warping algorithm, we quantify the timescale of the reinstatement and identify brain regions that show significant timescale differences between encoding and retrieval. Our data suggest that temporally compressed reinstatement of cortical activity is a feature of cued memory retrieval. SIGNIFICANCE STATEMENT We show that cued memory retrieval reinstates neural activity on a faster timescale than was present during encoding. Our data therefore provide a link between reinstatement of neural activity in the cortex and spontaneous replay of cortical and hippocampal spiking activity, which also exhibits temporal compression, and suggest that temporal compression may be a universal feature of memory retrieval. Copyright © 2017 the authors 0270-6474/17/374472-09$15.00/0.
Harland, S; Legge, G E; Luebker, A
1998-03-01
Most people with low vision need magnification to read. Page navigation is the process of moving a magnifier during reading. Modern electronic technology can provide many alternatives for navigating through text. This study compared reading speeds for four methods of displaying text. The four methods varied in their page-navigation demands. The closed-circuit television (CCTV) and MOUSE methods involved manual navigation. The DRIFT method (horizontally drifting text) involved no manual navigation, but did involve both smooth-pursuit and saccadic eye movements. The rapid serial visual presentation (RSVP) method involved no manual navigation, and relatively few eye movements. There were 7 normal subjects and 12 low-vision subjects (7 with central-field loss, CFL group, and 5 with central fields intact, CFI group). The subjects read 70-word passages at speeds that yielded good comprehension. Taking the CCTV reading speed as a benchmark, neither the normal nor low-vision subjects had significantly different speeds with the MOUSE method. As expected from the reduced navigational demands, normal subjects read faster with the DRIFT method (85% faster) and the RSVP method (169%). The CFI group read significantly faster with DRIFT (43%) and RSVP (38%). The CFL group showed no significant differences in reading speed for the four methods.
Sakadjian, Alex; Panchuk, Derek; Pearce, Alan J
2014-06-01
This study investigated the effectiveness of action observation (AO) on facilitating learning of the power clean technique (kinematics) compared with traditional strength coaching methods and whether improvements in performance (kinetics) were associated with an improvement in lifting technique. Fifteen subjects (age, 20.9 ± 2.3 years) with no experience in performing the power clean exercise attended 12 training and testing sessions over a 4-week period. Subjects were assigned to 2 matched groups, based on preintervention power clean performance and performed 3 sets of 5 repetitions of the power clean exercise at each training session. Subjects in the traditional coaching group (TC; n = 7) received the standard coaching feedback (verbal cues and physical practice), whereas subjects in the AO group (n = 8) received similar verbal coaching cues and physical practice but also observed a video of a skilled model before performing each set. Kinematic data were collected from video recordings of subjects who were fitted with joint center markings during testing, whereas kinetic data were collected from a weightlifting analyzer attached to the barbell. Subjects were tested before intervention, at the end of weeks 2 and 3, and at after intervention at the end of week 4. Faster improvements (3%) were observed in power clean technique with AO-facilitated learning in the first week and performance improvements (mean peak power of the subject's 15 repetitions) over time were significant (p < 0.001). In addition, performance improvement was significantly associated (R = 0.215) with technique improvements. In conclusion, AO combined with verbal coaching and physical practice of the power clean exercise resulted in significantly faster technique improvements and improvement in performance compared with traditional coaching methods.
The effect of an acute ingestion of Turkish coffee on reaction time and time trial performance.
Church, David D; Hoffman, Jay R; LaMonica, Michael B; Riffe, Joshua J; Hoffman, Mattan W; Baker, Kayla M; Varanoske, Alyssa N; Wells, Adam J; Fukuda, David H; Stout, Jeffrey R
2015-01-01
The purpose of this study was to examine the ergogenic benefits of Turkish coffee consumed an hour before exercise. In addition, metabolic, cardiovascular, and subjective measures of energy, focus and alertness were examined in healthy, recreationally active adults who were regular caffeine consumers (>200 mg per day). Twenty males (n = 10) and females (n = 10), age 24.1 ± 2.9 y; height 1.70 ± 0.09 m; body mass 73.0 ± 13.0 kg (mean ± SD), ingested both Turkish coffee [3 mg · kg(-1) BW of caffeine, (TC)], and decaffeinated Turkish coffee (DC) in a double-blind, randomized, cross-over design. Performance measures included a 5 km time trial, upper and lower body reaction to visual stimuli, and multiple object tracking. Plasma caffeine concentrations, blood pressure (BP), heart rate and subjective measures of energy, focus and alertness were assessed at baseline (BL), 30-min following coffee ingestion (30+), prior to endurance exercise (PRE) and immediately-post 5 km (IP). Metabolic measures [VO2, V E , and respiratory exchange rate (RER)] were measured during the 5 km. Plasma caffeine concentrations were significantly greater during TC (p < 0.001) at 30+, PRE, and IP compared to DC. Significantly higher energy levels were reported at 30+ and PRE for TC compared to DC. Upper body reaction performance (p = 0.023) and RER (p = 0.019) were significantly higher for TC (85.1 ± 11.6 "hits," and 0.98 ± 0.05 respectively) compared to DC (81.2 ± 13.7 "hits," and 0.96 ± 0.05, respectively). Although no significant differences (p = 0.192) were observed in 5 km run time, 12 of the 20 subjects ran faster (p = 0.012) during TC (1662 ± 252 s) compared to DC (1743 ± 296 s). Systolic BP was significantly elevated during TC in comparison to DC. No other differences (p > 0.05) were noted in any of the other performance or metabolic measures. Acute ingestion of TC resulted in a significant elevation in plasma caffeine concentrations within 30-min of consumption. TC ingestion resulted in significant performance benefits in reaction time and an increase in subjective feelings of energy in habitual caffeine users. No significant differences were noted in time for the 5 km between trials, however 60 % of the participants performed the 5 km faster during the TC trial and were deemed responders. When comparing TC to DC in responders only, significantly faster times were noted when consuming TC compared to DC. No significant benefits were noted in measures of cognitive function.
Yoga practice is associated with superior motor imagery performance.
Hartnoll, Susannah H; Punt, T David
2017-11-01
Yoga is an activity that aims to integrate physical, mental and spiritual elements and is an increasingly popular approach to enhancing physical fitness. The integration of imagery within yoga practice is considered an important component and may be critical in contributing to the benefits of yoga that have been reported. In this study, we tested whether individuals who practice yoga demonstrate superior performance on an objective measure of implicit motor imagery. Thirty-six participants (18 yoga, 18 non-yoga) matched for age, sex and handedness, undertook the hand laterality recognition task; an objective measure of implicit motor imagery performance. Accuracy and response times were gathered and analysed to determine any group differences as well as any differences relating to the typical hallmarks of imagery (i.e. dominance and awkwardness effects) on the task. Response Times (RTs) in the yoga group were significantly faster than controls (p < 0.05) and there was also a trend towards greater accuracy for the Yoga group (p = 0.073). Dominance effects (faster responses to images corresponding with the dominant limb) and Awkwardness effects (faster responses to images corresponding with natural compared with awkward postures) were evident across groups, supporting the participants' use of motor imagery in undertaking the task. Additionally, a Group × Awkwardness interaction (p < 0.05) revealed that the enhanced imagery performance for the yoga group was most pronounced for awkward postures. This is the first study to show that yoga practice is associated with superior motor imagery performance; an association that may be important in explaining the established rehabilitative value of yoga for chronic pain.
Yoga practice is associated with superior motor imagery performance.
Hartnoll, Susannah H; Punt, T David
2017-08-02
Yoga is an activity that aims to integrate physical, mental and spiritual elements and is an increasingly popular approach to enhancing physical fitness. The integration of imagery within yoga practice is considered an important component and may be critical in contributing to the benefits of yoga that have been reported. In this study, we tested whether individuals who practice yoga demonstrate superior performance on an objective measure of implicit motor imagery. Thirty-six participants (18 yoga, 18 nonyoga) matched for age, sex and handedness, undertook the hand laterality recognition task; an objective measure of implicit motor imagery performance. Accuracy and response times were gathered and analysed to determine any group differences as well as any differences relating to the typical hallmarks of imagery (i.e. dominance and awkwardness effects) on the task. Response Times (RTs) in the yoga group were significantly faster than controls (p < 0.05) and there was also a trend towards greater accuracy for the Yoga group (p = 0.073). Dominance effects (faster responses to images corresponding with the dominant limb) and Awkwardness effects (faster responses to images corresponding with natural compared with awkward postures) were evident across groups, supporting the participants' use of motor imagery in undertaking the task. Additionally, a Group × Awkwardness interaction (p < 0.05) revealed that the enhanced imagery performance for the yoga group was most pronounced for awkward postures. This is the first study to show that yoga practice is associated with superior motor imagery performance; an association that may be important in explaining the established rehabilitative value of yoga for chronic pain.
Kaland, Nils; Mortensen, Erik Lykke; Smith, Lars
2007-01-01
The aim of the present study was to assess the findings, reported in earlier studies, that individuals with autism spectrum disorders process visuo-spatial tasks faster than typically developing control persons. The participants in the present study were children and adolescents with Asperger syndrome (AS) or high-functioning autism (HFA) (N = 13), and a matched group of typically developing children and adolescents (N = 13). The results showed that the participants in the clinical group performed marginally less well than those in the control group on both the Block Design Test and the Embedded Figures Test, but the differences were not statistically significant. Thus, earlier findings suggesting that individuals with autism spectrum disorders solve non-social cognitive tasks faster than typically developing control persons were not replicated. The results are discussed with special reference to the hypothesis of weak central coherence.
Accelerating gravitational microlensing simulations using the Xeon Phi coprocessor
NASA Astrophysics Data System (ADS)
Chen, B.; Kantowski, R.; Dai, X.; Baron, E.; Van der Mark, P.
2017-04-01
Recently Graphics Processing Units (GPUs) have been used to speed up very CPU-intensive gravitational microlensing simulations. In this work, we use the Xeon Phi coprocessor to accelerate such simulations and compare its performance on a microlensing code with that of NVIDIA's GPUs. For the selected set of parameters evaluated in our experiment, we find that the speedup by Intel's Knights Corner coprocessor is comparable to that by NVIDIA's Fermi family of GPUs with compute capability 2.0, but less significant than GPUs with higher compute capabilities such as the Kepler. However, the very recently released second generation Xeon Phi, Knights Landing, is about 5.8 times faster than the Knights Corner, and about 2.9 times faster than the Kepler GPU used in our simulations. We conclude that the Xeon Phi is a very promising alternative to GPUs for modern high performance microlensing simulations.
Singer product apertures-A coded aperture system with a fast decoding algorithm
NASA Astrophysics Data System (ADS)
Byard, Kevin; Shutler, Paul M. E.
2017-06-01
A new type of coded aperture configuration that enables fast decoding of the coded aperture shadowgram data is presented. Based on the products of incidence vectors generated from the Singer difference sets, we call these Singer product apertures. For a range of aperture dimensions, we compare experimentally the performance of three decoding methods: standard decoding, induction decoding and direct vector decoding. In all cases the induction and direct vector methods are several orders of magnitude faster than the standard method, with direct vector decoding being significantly faster than induction decoding. For apertures of the same dimensions the increase in speed offered by direct vector decoding over induction decoding is better for lower throughput apertures.
Zamora-Camacho, Francisco Javier; Rubiño-Hispán, María Virtudes; Reguera, Senda; Moreno-Rueda, Gregorio
2015-08-01
Sprint speed has a capital relevance in most animals' fitness, mainly for fleeing from predators. Sprint performance is maximal within a certain range of body temperatures in ectotherms, whose thermal upkeep relies on exogenous thermal sources. Ectotherms can respond to diverse thermal environments either by shifting their thermal preferences or maintaining them through different adaptive mechanisms. Here, we tested whether maximum sprint speed of a lizard that shows conservative thermal ecology along a 2200-meter elevational gradient differs with body temperature in lizards from different elevations. Lizards ran faster at optimum than at suboptimum body temperature. Notably, high-elevation lizards were not faster than mid- and low-elevation lizards at suboptimum body temperature, despite their low-quality thermal environment. This result suggests that both preferred body temperature and thermal dependence of speed performance are co-adapted along the elevational gradient. High-elevation lizards display a number of thermoregulatory strategies that allow them to achieve high optimum body temperatures in a low thermal-quality habitat and thus maximize speed performance. As for reproductive condition, we did not find any effect of it on sprint speed, or any significant interaction with elevation or body temperature. However, strikingly, gravid females were significantly slower than males and non-gravid females at suboptimum temperature, but performed similarly well at optimal temperature. Copyright © 2015 Elsevier Ltd. All rights reserved.
Psychophysical estimation of the effects of aging on direction-of-heading judgments
NASA Astrophysics Data System (ADS)
Raghuram, Aparna; Lakshminarayanan, Vasudevan
2011-11-01
We conducted psychophysical experiments on direction-of-heading judgments using old and young subjects. Subjects estimated heading directions on a translation perpendicular to the vertical plane (frontoparallel); we found that heading judgments were affected by age. Increasing the random dot density in the stimulus from 24 to 400 dots did not improve threshold significantly. Older subjects started performing worse at the highest dots condition of 400. The speed of the radial motion was important, as heading judgments with slower radial motion were difficult to judge than faster radial motion, as the focus of expansion was easier to locate owing to the larger displacement of dots. Gender differences indicated that older women had a higher threshold than older men. This was only significant for the faster simulated radial speed. A general trend of women having a higher threshold than men was noticed.
Kinematical Comparison of the 200 m Backstroke Turns between National and Regional Level Swimmers
Veiga, Santiago; Cala, Antonio; Frutos, Pablo González; Navarro, Enrique
2013-01-01
The aims of this investigation were to determine the evolution of selected turn variables during competitive backstroke races and to compare these kinematic variables between two different levels of swimmers. Sixteen national and regional level male swimmers participant in the 200 m backstroke event at the Spanish Swimming Championships in short course (25 m) were selected to analyze their turn performances. The individual distances method with two-dimensional Direct Linear Transformation (2D-DLT) algorithms was used to perform race analyses. National level swimmers presented a shorter “turn time”, a longer “distance in”, a faster “underwater velocity” and “normalized underwater velocity”, and a faster “stroking velocity” than regional level swimmers, whereas no significant differences were detected between levels for the “underwater distance”. National level swimmers maintained similar “turn times” over the event and increased “underwater velocity” and “normalized underwater velocity” in the last (seventh) turn segment, whereas regional level swimmers increased “turn time” in the last half of the race. For both national and regional level swimmers, turn “underwater distance” during the last three turns of the race was significantly shorter while no significant differences in distance into the wall occurred throughout the race. The skill level of the swimmers has an impact on the competitive backstroke turn segments. In a 200 m event, the underwater velocity should be maximized to maintain turn proficiency, whereas turn distance must be subordinated to the average velocity. Key Points The underwater turn velocity is as a critical variable related to the swimmers’ level of skill in a 200 m backstroke event. Best swimmers perform faster but no longer turn segments during a 200 m backstroke event. Best swimmers maintain their turn performance throughout the 200 m backstroke event by increasing the underwater velocity during the final part of the race. The turn distance out seems to be subordinated in order to maximize the average velocity during a 200 m backstroke event. PMID:24421733
Kannenberg, Andreas; Zacharias, Britta; Pröbsting, Eva
2014-01-01
The benefits of microprocessor-controlled prosthetic knees (MPKs) have been well established in community ambulators (Medicare Functional Classification Level [MFCL]-3) with a transfemoral amputation (TFA). A systematic review of the literature was performed to analyze whether limited community ambulators (MFCL-2) may also benefit from using an MPK in safety, performance-based function and mobility, and perceived function and satisfaction. We searched 10 scientific databases for clinical trials with MPKs and identified six publications with 57 subjects with TFA and MFCL-2 mobility grade. Using the criteria of a Cochrane Review on prosthetic components, we rated methodological quality moderate in four publications and low in two publications. MPK use may significantly reduce uncontrolled falls by up to 80% as well as significantly improve indicators of fall risk. Performance-based outcome measures suggest that persons with MFCL-2 mobility grade may be able to walk about 14% to 25% faster on level ground, be around 20% quicker on uneven surfaces, and descend a slope almost 30% faster when using an MPK. The results of this systematic review suggest that trial fittings may be used to determine whether or not individuals with TFA and MFCL-2 mobility grade benefit from MPK use. Criteria for patient selection and assessment of trial fitting success or failure are proposed.
NASA Technical Reports Server (NTRS)
Hopkins, William D.; Washburn, David A.; Berke, Leslie; Williams, Mary
1992-01-01
Hand preferences were recorded for 35 rhesus monkeys (Macaca mulatta) as they manipulated a joystick in response to 2 computerized tasks. These preferences were then used to contrast 8 left- and 10 right-handed subjects on performance measures of hand skill. Individual hand preferences were found, but no significant population asymmetry was observed across the sample. However, the performance data reveal substantial benefits of right-handedness for joystick manipulation, as this group of monkeys mastered the 2 psychomotor tasks significantly faster than did their left-handed counterparts. The data support earlier reports of a right-hand advantage for joystick manipulation and also support the importance of distinguishing between hand preference and manual performance in research on functional asymmetries.
[A comparison between adults and children tonsillectomy with monopolar electrocautery].
Ao, Min; Deng, Jie; Gao, Lei; He, Gang
2015-02-01
Tonsillectomy is one of the most frequently applied operations in the ENT practice. This prospective study compared intraoperative records and postoperative clinical outcomes between adults and children patients following monopolar electrocautery tonsillectomy. Forty adult patients and Forty children patients with histories of recurrent tonsillitis or hypertrophic tonsillitis were enrolled. Intraoperative parameters and postoperative outcomes were compared. Children tonsillectomy with monopolar electrocautery was significantly faster to perform (P < 0.05), and produced significantly less intraoperative blood loss (P < 0.05), and faster to return to commencement of a regular diet (P < 0.05) than adults. Children tonsillectomy endured less postopera- tive pain within a week (P > 0.05) than adults, but there was no significant difference in pain on the 14th postoperative day in two groups. There was no obvious postoperative hemorrhage in two groups. There was no significant difference in postoperative tonsillar fossa healing and postoperative temperature between the groups. Children and adults tonsillectomy with monopolar electrocautery had clinical characteristics respectively. Monopolar electrocautery tonsillectomy was safe and operated easily in both two groups.
Morse, J; Terrasini, N; Wehbe, M; Philippona, C; Zaouter, C; Cyr, S; Hemmerling, T M
2014-06-01
This study focuses on a recently developed robotic nerve block system and its impact on learning regional anaesthesia skills. We compared success rates, learning curves, performance times, and inter-subject performance variability of robot-assisted vs manual ultrasound (US)-guided nerve block needle guidance. The hypothesis of this study is that robot assistance will result in faster skill acquisition than manual needle guidance. Five co-authors with different experience with nerve blocks and the robotic system performed both manual and robot-assisted, US-guided nerve blocks on two different nerves of a nerve phantom. Ten trials were performed for each of the four procedures. Time taken to move from a shared starting position till the needle was inserted into the target nerve was defined as the performance time. A successful block was defined as the insertion of the needle into the target nerve. Average performance times were compared using analysis of variance. P<0.05 was considered significant. Data presented as mean (standard deviation). All blocks were successful. There were significant differences in performance times between co-authors to perform the manual blocks, either superficial (P=0.001) or profound (P=0.0001); no statistical difference between co-authors was noted for the robot-assisted blocks. Linear regression indicated that the average decrease in time between consecutive trials for robot-assisted blocks of 1.8 (1.6) s was significantly (P=0.007) greater than the decrease for manual blocks of 0.3 (0.3) s. Robot assistance of nerve blocks allows for faster learning of needle guidance over manual positioning and reduces inter-subject performance variability. © The Author [2014]. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Gorman, Jamie C; Crites, Michael J
2013-08-01
We report an experiment in which we investigated differential transfer between unimanual (one-handed), bimanual (two-handed), and intermanual (different peoples' hands) coordination modes. People perform some manual tasks faster than others ("mode effects"). However, little is known about transfer between coordination modes. To investigate differential transfer, we draw hypotheses from two perspectives--information based and constraint based--of bimanual and interpersonal coordination and skill acquisition. Participants drove a teleoperated rover around a circular path in sets of two 2-min trials using two of the different coordination modes. Speed and variability of the rover's path were measured. Order of coordination modes was manipulated to examine differential transfer and mode effects. Differential transfer analyses revealed patterns of positive transfer from simpler (localized spatiotemporal constraints) to more complex (distributed spatiotemporal constraints) coordination modes paired with negative transfer in the opposite direction. Mode effects indicated that intermanual performance was significantly faster than unimanual performance, and bimanual performance was intermediate. Importantly, all of these effects disappeared with practice. The observed patterns of differential transfer between coordination modes may be better accounted for by a constraint-based explanation of differential transfer than by an information-based one. Mode effects may be attributable to anticipatory movements based on dyads' access to mutual visual information. Although people may be faster using more-complex coordination modes, when operators transition between modes, they may be more effective transitioning from simpler (e.g., bimanual) to more complex (e.g., intermanual) modes than vice versa. However, this difference may be critical only for novel or rarely practiced tasks.
NASA Astrophysics Data System (ADS)
Haake, Steve
2012-07-01
Sprinters are running faster than ever before, but why are javelin throwers not throwing further and swimmers not swimming faster? Steve Haake explains the effects of technology and rule change on sporting performance.
Takahashi, Kota Z; Stanhope, Steven J
2013-09-01
Over the last half-century, the field of prosthetic engineering has continuously evolved with much attention being dedicated to restoring the mechanical energy properties of ankle joint musculatures during gait. However, the contributions of 'distal foot structures' (e.g., foot muscles, plantar soft tissue) have been overlooked. Therefore, the purpose of this study was to quantify the total mechanical energy profiles (e.g., power, work, and work-ratio) of the natural ankle-foot system (NAFS) by combining the contributions of the ankle joint and all distal foot structures during stance in level-ground steady state walking across various speeds (0.4, 0.6, 0.8 and 1.0 statures/s). The results from eleven healthy subjects walking barefoot indicated ankle joint and distal foot structures generally performed opposing roles: the ankle joint performed net positive work that systematically increased its energy generation with faster walking speeds, while the distal foot performed net negative work that systematically increased its energy absorption with faster walking speeds. Accounting for these simultaneous effects, the combined ankle-foot system exhibited increased work-ratios with faster walking. Most notably, the work-ratio was not significantly greater than 1.0 during the normal walking speed of 0.8 statures/s. Therefore, a prosthetic design that strategically exploits passive-dynamic properties (e.g., elastic energy storage and return) has the potential to replicate the mechanical energy profiles of the NAFS during level-ground steady-state walking. Copyright © 2013 Elsevier B.V. All rights reserved.
Normative values and the effects of age, gender, and handedness on the Moberg Pick-Up Test.
Amirjani, Nasim; Ashworth, Nigel L; Gordon, Tessa; Edwards, David C; Chan, K Ming
2007-06-01
The Moberg Pick-Up Test is a standardized test for assessing hand dexterity. Although reduction of sensation in the hand occurs with aging, the effect of age on a subject's performance of the Moberg Pick-Up Test has not been examined. The primary goal of this study was to examine the impact of aging and, secondarily, the impact of gender and handedness, on performance of the Moberg Pick-Up Test in 116 healthy subjects. The average time to complete each of the four subsets of the test was analyzed using the Kruskal-Wallis, Mann-Whitney U, and Wilcoxon signed-rank tests. The results show that hand dexterity of the subjects was significantly affected by age, with young subjects being the fastest and elderly subjects the slowest. Women accomplished the test faster than men, and task performance with the dominant hand was faster than with the non-dominant hand. Use of normative values established based on age and gender is a valuable objective tool to gauge hand function in patients with different neurologic disorders.
The metabolic and performance effects of caffeine compared to coffee during endurance exercise.
Hodgson, Adrian B; Randell, Rebecca K; Jeukendrup, Asker E
2013-01-01
There is consistent evidence supporting the ergogenic effects of caffeine for endurance based exercise. However, whether caffeine ingested through coffee has the same effects is still subject to debate. The primary aim of the study was to investigate the performance enhancing effects of caffeine and coffee using a time trial performance test, while also investigating the metabolic effects of caffeine and coffee. In a single-blind, crossover, randomised counter-balanced study design, eight trained male cyclists/triathletes (Mean ± SD: Age 41 ± 7 y, Height 1.80 ± 0.04 m, Weight 78.9 ± 4.1 kg, VO2 max 58 ± 3 ml • kg(-1) • min(-1)) completed 30 min of steady-state (SS) cycling at approximately 55% VO2max followed by a 45 min energy based target time trial (TT). One hour prior to exercise each athlete consumed drinks consisting of caffeine (5 mg CAF/kg BW), instant coffee (5 mg CAF/kg BW), instant decaffeinated coffee or placebo. The set workloads produced similar relative exercise intensities during the SS for all drinks, with no observed difference in carbohydrate or fat oxidation. Performance times during the TT were significantly faster (~5.0%) for both caffeine and coffee when compared to placebo and decaf (38.35 ± 1.53, 38.27 ± 1.80, 40.23 ± 1.98, 40.31 ± 1.22 min respectively, p<0.05). The significantly faster performance times were similar for both caffeine and coffee. Average power for caffeine and coffee during the TT was significantly greater when compared to placebo and decaf (294 ± 21 W, 291 ± 22 W, 277 ± 14 W, 276 ± 23 W respectively, p<0.05). No significant differences were observed between placebo and decaf during the TT. The present study illustrates that both caffeine (5 mg/kg/BW) and coffee (5 mg/kg/BW) consumed 1 h prior to exercise can improve endurance exercise performance.
The Metabolic and Performance Effects of Caffeine Compared to Coffee during Endurance Exercise
Hodgson, Adrian B.; Randell, Rebecca K.; Jeukendrup, Asker E.
2013-01-01
There is consistent evidence supporting the ergogenic effects of caffeine for endurance based exercise. However, whether caffeine ingested through coffee has the same effects is still subject to debate. The primary aim of the study was to investigate the performance enhancing effects of caffeine and coffee using a time trial performance test, while also investigating the metabolic effects of caffeine and coffee. In a single-blind, crossover, randomised counter-balanced study design, eight trained male cyclists/triathletes (Mean±SD: Age 41±7y, Height 1.80±0.04 m, Weight 78.9±4.1 kg, VO2 max 58±3 ml•kg−1•min−1) completed 30 min of steady-state (SS) cycling at approximately 55% VO2max followed by a 45 min energy based target time trial (TT). One hour prior to exercise each athlete consumed drinks consisting of caffeine (5 mg CAF/kg BW), instant coffee (5 mg CAF/kg BW), instant decaffeinated coffee or placebo. The set workloads produced similar relative exercise intensities during the SS for all drinks, with no observed difference in carbohydrate or fat oxidation. Performance times during the TT were significantly faster (∼5.0%) for both caffeine and coffee when compared to placebo and decaf (38.35±1.53, 38.27±1.80, 40.23±1.98, 40.31±1.22 min respectively, p<0.05). The significantly faster performance times were similar for both caffeine and coffee. Average power for caffeine and coffee during the TT was significantly greater when compared to placebo and decaf (294±21 W, 291±22 W, 277±14 W, 276±23 W respectively, p<0.05). No significant differences were observed between placebo and decaf during the TT. The present study illustrates that both caffeine (5 mg/kg/BW) and coffee (5 mg/kg/BW) consumed 1 h prior to exercise can improve endurance exercise performance. PMID:23573201
Semantic size does not matter: "bigger" words are not recognized faster.
Kang, Sean H K; Yap, Melvin J; Tse, Chi-Shing; Kurby, Christopher A
2011-06-01
Sereno, O'Donnell, and Sereno (2009) reported that words are recognized faster in a lexical decision task when their referents are physically large than when they are small, suggesting that "semantic size" might be an important variable that should be considered in visual word recognition research and modelling. We sought to replicate their size effect, but failed to find a significant latency advantage in lexical decision for "big" words (cf. "small" words), even though we used the same word stimuli as Sereno et al. and had almost three times as many subjects. We also examined existing data from visual word recognition megastudies (e.g., English Lexicon Project) and found that semantic size is not a significant predictor of lexical decision performance after controlling for the standard lexical variables. In summary, the null results from our lab experiment--despite a much larger subject sample size than Sereno et al.--converged with our analysis of megastudy lexical decision performance, leading us to conclude that semantic size does not matter for word recognition. Discussion focuses on why semantic size (unlike some other semantic variables) is unlikely to play a role in lexical decision.
Motes, Michael A; Yezhuvath, Uma S; Aslan, Sina; Spence, Jeffrey S; Rypma, Bart; Chapman, Sandra B
2018-02-01
Higher-order cognitive training has shown to enhance performance in older adults, but the neural mechanisms underlying performance enhancement have yet to be fully disambiguated. This randomized trial examined changes in processing speed and processing speed-related neural activity in older participants (57-71 years of age) who underwent cognitive training (CT, N = 12) compared with wait-listed (WLC, N = 15) or exercise-training active (AC, N = 14) controls. The cognitive training taught cognitive control functions of strategic attention, integrative reasoning, and innovation over 12 weeks. All 3 groups worked through a functional magnetic resonance imaging processing speed task during 3 sessions (baseline, mid-training, and post-training). Although all groups showed faster reaction times (RTs) across sessions, the CT group showed a significant increase, and the WLC and AC groups showed significant decreases across sessions in the association between RT and BOLD signal change within the left prefrontal cortex (PFC). Thus, cognitive training led to a change in processing speed-related neural activity where faster processing speed was associated with reduced PFC activation, fitting previously identified neural efficiency profiles. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.
[Are there any differences in the working memory of men and women?].
Talarowska, Monika; Florkowski, Antoni; Chamielec, Marcelina; Gałecki, Piotr
2013-01-01
The aim of the study was to compare the implementation of the Stroop test among women and men and to answer the question of the existence of differences in verbal working memory performance and efficiency of attention between representatives of both sexes. A sample of 348 persons aged 20-68 years (mean age: M = 42.16 years) participated in the study: 187 women (53.73%) and 161 men (42.26%). Patients who took part in the investigation were divided into several groups: depressive disorders (DD, n = 146), diabetes type 1 (DM1, n = 31), diabetes type 2 (DM2, n = 31), patients with hypertension (HA, n = 30) and healthy controls (HC, n=110). Cognitive functions were evaluated by the Stroop test. There were no significant differences between men and women in making the first (p = 0.831) and the second part of the Stroop test (p = 0.055). However, it should be noted that the difference between men and 'omen in the speed of the second part of the test is close to significance. Women performed the test faster than men, while men have committed in other parts of the test less errors (p = 0.441). In the present study there was no statistically significant differences between men and women in the implementation of both parts of the Stroop test. Women performed both part of the Stroop test faster than men do but the latter make fewer mistakes.
The Structure of Working Memory Abilities across the Adult Life Span
Hale, Sandra; Rose, Nathan S.; Myerson, Joel; Strube, Michael J; Sommers, Mitchell; Tye-Murray, Nancy; Spehar, Brent
2010-01-01
The present study addresses three questions regarding age differences in working memory: (1) whether performance on complex span tasks decreases as a function of age at a faster rate than performance on simple span tasks; (2) whether spatial working memory decreases at a faster rate than verbal working memory; and (3) whether the structure of working memory abilities is different for different age groups. Adults, ages 20–89 (n=388), performed three simple and three complex verbal span tasks and three simple and three complex spatial memory tasks. Performance on the spatial tasks decreased at faster rates as a function of age than performance on the verbal tasks, but within each domain, performance on complex and simple span tasks decreased at the same rates. Confirmatory factor analyses revealed that domain-differentiated models yielded better fits than models involving domain-general constructs, providing further evidence of the need to distinguish verbal and spatial working memory abilities. Regardless of which domain-differentiated model was examined, and despite the faster rates of decrease in the spatial domain, age group comparisons revealed that the factor structure of working memory abilities was highly similar in younger and older adults and showed no evidence of age-related dedifferentiation. PMID:21299306
Movement amplitude and tempo change in piano performance
NASA Astrophysics Data System (ADS)
Palmer, Caroline
2004-05-01
Music performance places stringent temporal and cognitive demands on individuals that should yield large speed/accuracy tradeoffs. Skilled piano performance, however, shows consistently high accuracy across a wide variety of rates. Movement amplitude may affect the speed/accuracy tradeoff, so that high accuracy can be obtained even at very fast tempi. The contribution of movement amplitude changes in rate (tempo) is investigated with motion capture. Cameras recorded pianists with passive markers on hands and fingers, who performed on an electronic (MIDI) keyboard. Pianists performed short melodies at faster and faster tempi until they made errors (altering the speed/accuracy function). Variability of finger movements in the three motion planes indicated most change in the plane perpendicular to the keyboard across tempi. Surprisingly, peak amplitudes of motion before striking the keys increased as tempo increased. Increased movement amplitudes at faster rates may reduce or compensate for speed/accuracy tradeoffs. [Work supported by Canada Research Chairs program, HIMH R01 45764.
Lacreuse, Agnès; Moore, Constance M; LaClair, Matthew; Payne, Laurellee; King, Jean A
2018-07-02
This study used Magnetic Resonance Spectroscopy (MRS) to identify potential neurometabolitic markers of cognitive performance in male (n = 7) and female (n = 8) middle-aged (∼5 years old) common marmosets (Callithrix jacchus). Anesthetized marmosets were scanned with a 4.7 T/40 cm horizontal magnet equipped with 450 mT/m magnetic field gradients and a 20 G/cm magnetic field gradient insert, within 3 months of completing the CANTAB serial Reversal Learning task. Neurometabolite concentrations of N-Acetyl Asparate, Myo-Inositol, Choline, Phosphocreatine + creatine, Glutamate and Glutamine were acquired from a 3 mm 3 voxel positioned in the Prefrontal Cortex (PFC). Males acquired the reversals (but not simple discriminations) faster than the females. Higher PFC Glx (glutamate + glutamine) concentration was associated with faster acquisition of the reversals. Interestingly, the correlation between cognitive performance and Glx was significant in males, but not in females. These results suggest that MRS is a useful tool to identify biochemical markers of cognitive performance in the healthy nonhuman primate brain and that biological sex modulates the relationship between neurochemical composition and cognition. Copyright © 2018 Elsevier B.V. All rights reserved.
Exploring the perceptual biases associated with believing and disbelieving in paranormal phenomena.
Simmonds-Moore, Christine
2014-08-01
Ninety-five participants (32 believers, 30 disbelievers and 33 neutral believers in the paranormal) participated in an experiment comprising one visual and one auditory block of trials. Each block included one ESP, two degraded stimuli and one random trial. Each trial included 8 screens or epochs of "random" noise. Participants entered a guess if they perceived a stimulus or changed their mind about stimulus identity, rated guesses for confidence and made notes during each trial. Believers and disbelievers did not differ in the number of guesses made, or in their ability to detect degraded stimuli. Believers displayed a trend toward making faster guesses for some conditions and significantly higher confidence and more misidentifications concerning guesses than disbelievers. Guesses, misidentifications and faster response latencies were generally more likely in the visual than auditory conditions. ESP performance was no different from chance. ESP performance did not differ between belief groups or sensory modalities. Copyright © 2014 Elsevier Inc. All rights reserved.
Otwell, Anne E; Callister, Stephen J; Sherwood, Robert W; Zhang, Sheng; Goldman, Abby R; Smith, Richard D; Richardson, Ruth E
2018-06-15
We established Fe(III)-reducing co-cultures of two species of metal-reducing bacteria, the Gram-positive Desulfotomaculum reducens MI-1 and the Gram-negative Geobacter sulfurreducens PCA. Co-cultures were given pyruvate, a substrate that D. reducens can ferment and use as electron donor for Fe(III) reduction. G. sulfurreducens relied upon products of pyruvate oxidation by D. reducens (acetate, hydrogen) for use as electron donor in the co-culture. Co-cultures reduced Fe(III) to Fe(II) robustly, and Fe(II) was consistently detected earlier in co-cultures than pure cultures. Notably, faster cell growth, and correspondingly faster pyruvate oxidation, was observed by D. reducens in co-cultures. Global comparative proteomic analysis was performed to observe differential protein abundance during co-culture vs. pure culture growth. Proteins previously associated with Fe(III) reduction in G. sulfurreducens, namely c-type cytochromes and type IV pili proteins, were significantly increased in abundance in co-cultures relative to pure cultures. D. reducens ribosomal proteins were significantly increased in co-cultures, likely a reflection of faster growth rates observed for D. reducens cells while in co-culture. Furthermore, we developed multiple reaction monitoring (MRM) assays to quantitate specific biomarker peptides. The assays were validated in pure and co-cultures, and protein abundance ratios from targeted MRM and global proteomic analysis correlate significantly. © 2018 John Wiley & Sons Ltd.
Effects of Greek orthodox christian church fasting on serum lipids and obesity
Sarri, Katerina O; Tzanakis, Nikolaos E; Linardakis, Manolis K; Mamalakis, George D; Kafatos, Anthony G
2003-01-01
Background No study to date has focused on the impact of Greek Orthodox Christian fasting on serum lipoproteins and obesity yet. Methods 120 Greek adults were followed longitudinally for one year. Sixty fasted regularly in all fasting periods (fasters) and 60 did not fast at all (controls). The three major fasting periods under study were: Christmas (40 days), Lent (48 days) and Assumption (August, 15 days). A total of 6 measurements were made during one year including pre- and end-fasting blood collection, serum lipoprotein analyses and anthropometric measurements. Results Statistically significant end-fasting total and LDL cholesterol differences were found in fasters. Fasters compared to controls presented 12.5% lower end-total cholesterol (p < 0.001), 15.9% lower end-LDL cholesterol (p < 0.001) and 1.5% lower end-BMI (p < 0.001). The end- LDL/HDL ratio was lower in fasters (6.5%, p < 0.05) while the change in end- HDL cholesterol in fasters (4.6% decline) was not significant. Similar results were found when the pre- and end-fasting values of fasters were compared. No change was found in control subjects. Conclusions Adherence to Greek Orthodox fasting periods contributes to a reduction in the blood lipid profile including a non-significant reduction in HDL cholesterol and possible impact on obesity. PMID:12753698
Nanostructural evolution and behavior of H and Li in ion-implanted γ-LiAlO 2
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jiang, Weilin; Zhang, Jiandong; Edwards, Danny J.
In-situ He+ ion irradiation is performed under a helium ion microscope to study nanostructural evolution in polycrystalline gamma-LiAlO2 pellets. Various locations within a grain, across grain boundaries and at a cavity are selected. The results exhibit He bubble formation, grain-boundary cracking, nanoparticle agglomeration, increasing surface brightness with dose, and material loss from the surface. Similar brightening effects at grain boundaries are also observed under a scanning electron microscope. Li diffusion and loss from polycrystalline gamma-LiAlO2 is faster than its monocrystalline counterpart during H2+ ion implantation at elevated temperatures. There is also more significant H diffusion and release from polycrystalline pelletsmore » during thermal annealing of 300 K implanted samples. Grain boundaries and cavities could provide a faster pathway for H and Li diffusion. H release is slightly faster from the 573 K implanted monocrystalline gamma-LiAlO2 during annealing at 773 K. Metal hydrides could be formed preferentially along the grain boundaries to immobilize hydrogen.« less
Control of a Robotic Hand Using a Tongue Control System-A Prosthesis Application.
Johansen, Daniel; Cipriani, Christian; Popovic, Dejan B; Struijk, Lotte N S A
2016-07-01
The aim of this study was to investigate the feasibility of using an inductive tongue control system (ITCS) for controlling robotic/prosthetic hands and arms. This study presents a novel dual modal control scheme for multigrasp robotic hands combining standard electromyogram (EMG) with the ITCS. The performance of the ITCS control scheme was evaluated in a comparative study. Ten healthy subjects used both the ITCS control scheme and a conventional EMG control scheme to complete grasping exercises with the IH1 Azzurra robotic hand implementing five grasps. Time to activate a desired function or grasp was used as the performance metric. Statistically significant differences were found when comparing the performance of the two control schemes. On average, the ITCS control scheme was 1.15 s faster than the EMG control scheme, corresponding to a 35.4% reduction in the activation time. The largest difference was for grasp 5 with a mean AT reduction of 45.3% (2.38 s). The findings indicate that using the ITCS control scheme could allow for faster activation of specific grasps or functions compared with a conventional EMG control scheme. For transhumeral and especially bilateral amputees, the ITCS control scheme could have a significant impact on the prosthesis control. In addition, the ITCS would provide bilateral amputees with the additional advantage of environmental and computer control for which the ITCS was originally developed.
Qin, Xiaoyan Angela; Koutstaal, Wilma; Engel, Stephen A
2014-05-01
Familiar items are found faster than unfamiliar ones in visual search tasks. This effect has important implications for cognitive theory, because it may reveal how mental representations of commonly encountered items are changed by experience to optimize performance. It remains unknown, however, whether everyday items with moderate levels of exposure would show benefits in visual search, and if so, what kind of experience would be required to produce them. Here, we tested whether familiar product logos were searched for faster than unfamiliar ones, and also familiarized subjects with previously unfamiliar logos. Subjects searched for preexperimentally familiar and unfamiliar logos, half of which were familiarized in the laboratory, amongst other, unfamiliar distractor logos. In three experiments, we used an N-back-like familiarization task, and in four others we used a task that asked detailed questions about the perceptual aspects of the logos. The number of familiarization exposures ranged from 30 to 84 per logo across experiments, with two experiments involving across-day familiarization. Preexperimentally familiar target logos were searched for faster than were unfamiliar, nonfamiliarized logos, by 8 % on average. This difference was reliable in all seven experiments. However, familiarization had little or no effect on search speeds; its average effect was to improve search times by 0.7 %, and its effect was significant in only one of the seven experiments. If priming, mere exposure, episodic memory, or relatively modest familiarity were responsible for familiarity's effects on search, then performance should have improved following familiarization. Our results suggest that the search-related advantage of familiar logos does not develop easily or rapidly.
Investigation of fiber-reinforced self-consolidating concrete.
DOT National Transportation Integrated Search
2010-05-01
The rising cost of materials and labor, as well as the demand for faster construction, has prompted development of cheaper, faster alternatives to conventional building techniques. Self-consolidating concrete (SCC), a high performance concrete charac...
Practical 3D Printing of Antennas and RF Electronics
2017-03-01
Passive RF; Combiners Introduction Additive manufacturing can reduce the time and material costs in a design cycle and enable the on-demand printing of...performance, and create Computer Assisted Manufacturing (CAM) files. By intelligently leveraging this process, the design can be readily updated or...advances in 3D printing technology now enable antennas and RF electronics to be designed and prototyped significantly faster than conventional
Electric Power from Cryo (Nano) Ice
NASA Astrophysics Data System (ADS)
Kandasamy, A.; Chandran, M.
2017-05-01
In this paper, the authors have studied experimentally the performance of cryocooler which is a mechanical device for producing very low temperature with significant cooling capacity. Nano particles were administrated to enhance the faster rate of cooling. Electric power (energy) was produced from cryogenic (nano) ice with help of thermoelectric effect. The governing equations for energy conversions, cooling capacity, amount of electric power was also discussed.
Orthographic recognition in late adolescents: an assessment through event-related brain potentials.
González-Garrido, Andrés Antonio; Gómez-Velázquez, Fabiola Reveca; Rodríguez-Santillán, Elizabeth
2014-04-01
Reading speed and efficiency are achieved through the automatic recognition of written words. Difficulties in learning and recognizing the orthography of words can arise despite reiterative exposure to texts. This study aimed to investigate, in native Spanish-speaking late adolescents, how different levels of orthographic knowledge might result in behavioral and event-related brain potential differences during the recognition of orthographic errors. Forty-five healthy high school students were selected and divided into 3 equal groups (High, Medium, Low) according to their performance on a 5-test battery of orthographic knowledge. All participants performed an orthographic recognition task consisting of the sequential presentation of a picture (object, fruit, or animal) followed by a correctly, or incorrectly, written word (orthographic mismatch) that named the picture just shown. Electroencephalogram (EEG) recording took place simultaneously. Behavioral results showed that the Low group had a significantly lower number of correct responses and increased reaction times while processing orthographical errors. Tests showed significant positive correlations between higher performance on the experimental task and faster and more accurate reading. The P150 and P450 components showed higher voltages in the High group when processing orthographic errors, whereas N170 seemed less lateralized to the left hemisphere in the lower orthographic performers. Also, trials with orthographic errors elicited a frontal P450 component that was only evident in the High group. The present results show that higher levels of orthographic knowledge correlate with high reading performance, likely because of faster and more accurate perceptual processing, better visual orthographic representations, and top-down supervision, as the event-related brain potential findings seem to suggest.
Briars, Graham L; Gordon, Gillian Suzanne; Lawrence, Andrew; Turner, Andrew; Perry, Sharon; Pillbrow, Dan; Walston, Florence Einstein; Molyneux, Paul
2017-01-01
To determine whether during-exercise rehydration improves swimming performance and whether sports drink or water have differential effects on performance. Randomised controlled multiple crossover trial. A UK competitive swimming club. 19 club-level competitive swimmers, median age (range) 13 (11-17) years. Subjects were scheduled to drink ad libitum commercial isotonic sports drink (3.9 g sugars and 0.13 g salt per 100 mL) or water (three sessions each) or no drink (six sessions) in the course of twelve 75 min training sessions, each of which was followed by a 30 min test set of ten 100 m maximum-effort freestyle sprints each starting at 3 min intervals. Times for the middle 50 m of each sprint measured using electronic timing equipment in a Federation Internationale de Natation (FINA)-compliant six-lane 25 m competition swimming pool. Software-generated individual random session order in sealed envelopes. Analysis subset of eight sessions randomly selected by software after data collection completed. Participants blind to drink allocation until session start. In the analysis data set of 1118 swims, there was no significant difference between swim times for drinking and not drinking nor between drinking water or a sports drink. Mean (SEM) 50 m time for no-drink swims was 38.077 (0.128) s and 38.105 (0.131) s for drink swims, p=0.701. Mean 50 m times were 38.031 (0.184) s for drinking sports drink and 38.182 (0.186) s for drinking water, p=0.073. Times after not drinking were 0.027 s faster than after drinking (95% CI 0.186 s faster to 0.113 s slower). Times after drinking sports drink were 0.151 s faster than after water (95% CI 0.309 s faster to 0.002 s slower). Mean (SEM) dehydration from exercise was 0.42 (0.11)%. Drinking water or sports drink over 105 min of sustained effort swimming training does not improve swimming performance. ISRCTN: 49860006.
Finger force changes in the absence of visual feedback in patients with Parkinson’s disease
Jo, Hang Jin; Ambike, Satyajit; Lewis, Mechelle M.; Huang, Xuemei; Latash, Mark L.
2015-01-01
Objectives We investigated the unintentional drift in total force and in sharing of the force between fingers in two-finger accurate force production tasks performed without visual feedback by patients with Parkinson’s disease (PD) and healthy controls. In particular, we were testing a hypothesis that adaptation to the documented loss of action stability could lead to faster force drop in PD. Methods PD patients and healthy controls performed accurate constant force production tasks without visual feedback by different finger pairs, starting with different force levels and different sharing patterns of force between the two fingers. Results Both groups showed an exponential force drop with time and a drift of the sharing pattern towards 50:50. The PD group showed a significantly faster force drop without a change in speed of the sharing drift. These results were consistent across initial force levels, sharing patterns, and finger pairs. A pilot test of four subjects, two PD and two controls, showed no consistent effects of memory on the force drop. Conclusions We interpret the force drop as a consequence of back-coupling between the actual and referent finger coordinates that draws the referent coordinate towards the actual one. The faster force drop in the PD group is interpreted as adaptive to the loss of action stability in PD. The lack of group differences in the sharing drift suggests two potentially independent physiological mechanisms contributing to the force and sharing drifts. Significance The hypothesis on adaptive changes in PD with the purpose to ensure stability of steady states may have important implications for treatment of PD. The speed of force drop may turn into a useful tool to quantify such adaptive changes. PMID:26072437
Liu, Shawn; Vaillancourt, Christian; Kasaboski, Ann; Taljaard, Monica
2016-11-01
This study sought to measure bystander fatigue and cardiopulmonary resuscitation (CPR) quality after five minutes of CPR using the continuous chest compression (CCC) versus the 30:2 chest compression to ventilation method in older lay persons, a population most likely to perform CPR on cardiac arrest victims. This randomized crossover trial took place at three tertiary care hospitals and a seniors' center. Participants were aged ≥55 years without significant physical limitations (frailty score ≤3/7). They completed two 5-minute CPR sessions (using 30:2 and CCC) on manikins; sessions were separated by a rest period. We used concealed block randomization to determine CPR method order. Metronome feedback maintained a compression rate of 100/minute. We measured heart rate (HR), mean arterial pressure (MAP), and Borg Exertion Scale. CPR quality measures included total number of compressions and number of adequate compressions (depth ≥5 cm). Sixty-three participants were enrolled: mean age 70.8 years, female 66.7%, past CPR training 60.3%. Bystander fatigue was similar between CPR methods: mean difference in HR -0.59 (95% CI -3.51-2.33), MAP 1.64 (95% CI -0.23-3.50), and Borg 0.46 (95% CI 0.07-0.84). Compared to 30:2, participants using CCC performed more chest compressions (480.0 v. 376.3, mean difference 107.7; p<0.0001) and more adequate chest compressions (381.5 v. 324.9, mean difference. 62.0; p=0.0001), although good compressions/minute declined significantly faster with the CCC method (p=0.0002). CPR quality decreased significantly faster when performing CCC compared to 30:2. However, performing CCC produced more adequate compressions overall with a similar level of fatigue compared to the 30:2 method.
Van Bruwaene, Siska; Schijven, Marlies P; Napolitano, Daniel; De Win, Gunter; Miserez, Marc
2015-01-01
As conventional laparoscopic procedural training requires live animals or cadaver organs, virtual simulation seems an attractive alternative. Therefore, we compared the transfer of training for the laparoscopic cholecystectomy from porcine cadaver organs vs virtual simulation to surgery in a live animal model in a prospective randomized trial. After completing an intensive training in basic laparoscopic skills, 3 groups of 10 participants proceeded with no additional training (control group), 5 hours of cholecystectomy training on cadaver organs (= organ training) or proficiency-based cholecystectomy training on the LapMentor (= virtual-reality training). Participants were evaluated on time and quality during a laparoscopic cholecystectomy on a live anaesthetized pig at baseline, 1 week (= post) and 4 months (= retention) after training. All research was performed in the Center for Surgical Technologies, Leuven, Belgium. In total, 30 volunteering medical students without prior experience in laparoscopy or minimally invasive surgery from the University of Leuven (Belgium). The organ training group performed the procedure significantly faster than the virtual trainer and borderline significantly faster than control group at posttesting. Only 1 of 3 expert raters suggested significantly better quality of performance of the organ training group compared with both the other groups at posttesting (p < 0.01). There were no significant differences between groups at retention testing. The virtual trainer group did not outperform the control group at any time. For trainees who are proficient in basic laparoscopic skills, the long-term advantage of additional procedural training, especially on a virtual but also on the conventional organ training model, remains to be proven. Copyright © 2015 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.
Effect of heavy back squats on repeated sprint performance in trained men.
Duncan, M J; Thurgood, G; Oxford, S W
2014-04-01
This study examined the impact of post activation potentiation on repeated sprint performance in trained Rugby Union players. Ten, male, professional Rugby Union players (mean age=25.2±5.02 years) performed 7, 30-meter sprints, separated by 25 seconds, 4 minutes following back squats (90% 1 repetition maximum) or a control condition performed in a counterbalanced order. Significant condition X sprint interactions for 10-meter (P=0.02) and 30-meter (P=0.05) indicated that times were significantly faster in the PAP condition for sprints 5, 6 and 7 across both distances. Fatigue rate was also significantly lower in the PAP condition for 10-meter (P=0.023) and 30-meter (P=0.006) sprint running speed. This study evidences that a heavy resistance exercise stimulus administered four minutes prior to repeated sprints can offset the decline in sprint performance seen during subsequent maximal sprinting over 10 and 30-meters in Rugby Union players.
Gender Differences in Physical Performance Characteristics of Elite Surfers.
Parsonage, Joanna R; Secomb, Josh L; Tran, Tai T; Farley, Oliver R L; Nimphius, Sophia; Lundgren, Lina; Sheppard, Jeremy M
2017-09-01
Parsonage, JR, Secomb, JL, Tran, TT, Farley, ORL, Nimphius, S, Lundgren, L, and Sheppard, JM. Gender differences in physical performance characteristics of elite surfers. J Strength Cond Res 31(9): 2417-2422, 2017-The purpose of this study was to describe and compare the gender differences in physical performance characteristics of elite surfers. Twenty competitive female surfers (CFS) and 20 competitive male surfers (CMS) performed a battery of physical performance tests: squat jump (SJ), isometric midthigh pull (IMTP), 15-m sprint paddle, and 400-m endurance paddle during a single testing session. All performance measures were significantly different between CFS and CMS (p < 0.01). Specifically, CMS produced greater peak force production (28.5%) and jumped higher (27.7%) in the SJ and produced greater normalized peak force during the IMTP (18.9%) compared with CFS. For paddling performance, CMS were faster over 5, 10, and 15 m (12.4%, 9.7%, and 10.9%), possessed a higher peak paddling velocity (11.3%), and recorded faster paddle times over 400 m (11.8%). The results of this study suggest that CMS exhibit superior physical performance characteristics than CFS, in relation to both the lower and upper body. Strength and conditioning practitioners should therefore implement a structured and periodized program to facilitate strength qualities that underpin surfing performance for all participants, but as highlighted in the current investigation, female surfers may have a greater window for adaptation and therefore vast benefit of targeting their underdeveloped physical qualities.
Taylor, Daniel; Smith, Mark F.
2017-01-01
Purpose: To examine the effects of deceptively aggressive bike pacing on performance, pacing, and associated physiological and perceptual responses during simulated sprint-distance triathlon. Methods: Ten non-elite, competitive male triathletes completed three simulated sprint-distance triathlons (0.75 km swim, 500 kJ bike, 5 km run), the first of which established personal best “baseline” performance (BL). During the remaining two trials athletes maintained a cycling power output 5% greater than BL, before completing the run as quickly as possible. However, participants were informed of this aggressive cycling strategy before and during only one of the two trials (HON). Prior to the alternate trial (DEC), participants were misinformed that cycling power output would equal that of BL, with on-screen feedback manipulated to reinforce this deception. Results: Compared to BL, a significantly faster run performance was observed following DEC cycling (p < 0.05) but not following HON cycling (1348 ± 140 vs. 1333 ± 129 s and 1350 ± 135 s, for BL, DEC, and HON, respectively). As such, magnitude-based inferences suggest HON running was more likely to be slower, than faster, compared to BL, and that DEC running was probably faster than both BL and HON. Despite a trend for overall triathlon performance to be quicker during DEC (4339 ± 395 s) compared to HON (4356 ± 384 s), the only significant and almost certainly meaningful differences were between each of these trials and BL (4465 ± 420 s; p < 0.05). Generally, physiological and perceptual strain increased with higher cycling intensities, with little, if any, substantial difference in physiological and perceptual response during each triathlon run. Conclusions: The present study is the first to show that mid-event pace deception can have a practically meaningful effect on multi-modal endurance performance, though the relative importance of different psychophysiological and emotional responses remains unclear. Whilst our findings support the view that some form of anticipatory “template” may be used by athletes to interpret levels of psychophysiological and emotional strain, and regulate exercise intensity accordingly, they would also suggest that individual constructs such as RPE and affect may be more loosely tied with pacing than previously suggested. PMID:28174540
Reactivity, stability, and strength performance capacity in motor sports.
Baur, H; Müller, S; Hirschmüller, A; Huber, G; Mayer, F
2006-11-01
Racing drivers require multifaceted cognitive and physical abilities in a multitasking situation. A knowledge of their physical capacities may help to improve fitness and performance. To compare reaction time, stability performance capacity, and strength performance capacity of élite racing drivers with those of age-matched, physically active controls. Eight élite racing drivers and 10 physically active controls matched for age and weight were tested in a reaction and determination test requiring upper and lower extremity responses to visual and audio cues. Further tests comprised evaluation of one-leg postural stability on a two-dimensional moveable platform, measures of maximum strength performance capacity of the extensors of the leg on a leg press, and a test of force capacity of the arms in a sitting position at a steering wheel. An additional arm endurance test consisted of isometric work at the steering wheel at +30 degrees and -30 degrees where an eccentric threshold load of 30 N.m was applied. Subjects had to hold the end positions above this threshold until exhaustion. Univariate one way analysis of variance (alpha = 0.05) including a Bonferroni adjustment was used to detect group differences between the drivers and controls. The reaction time of the racing drivers was significantly faster than the controls (p = 0.004). The following motor reaction time and reaction times in the multiple determination test did not differ between the groups. No significant differences (p>0.05) were found for postural stability, leg extensor strength, or arm strength and endurance. Racing drivers have faster reaction times than age-matched physically active controls. Further development of motor sport-specific test protocols is suggested. According to the requirements of motor racing, strength and sensorimotor performance capacity can potentially be improved.
Ramadan fasting in patients with adrenal insufficiency.
Chihaoui, Mélika; Chaker, Fatma; Yazidi, Meriem; Grira, Wafa; Ben Amor, Zohra; Rejeb, Ons; Slimane, Hedia
2017-01-01
The risks of fasting during Ramadan in patients with adrenal insufficiency are unknown. The aims of this study were to evaluate these risks in such patients, to determine the risk factors and finally to set some recommendations. It is a cross-sectional study about 180 patients with known and treated adrenal insufficiency. The patients responded to a 14-item questionnaire concerning their knowledge about the disease and fasting during the last month of Ramadan. There were 132 women and 48 men. The mean age was 47.6 ± 15.0 years (14-79). One hundred and thirty eight patients (76.7 %) were advised by their physician not to fast. Ninety-one patients (50.5 %) tried to fast. Complications occurred in 61 cases (67.0 %): asthenia in 88.5 % of cases, intense thirst in 32.8 %, symptoms of dehydration in 49.2 % and symptoms of hypoglycaemia in 18 %. One patient was hospitalized. Fifty-five patients (60.4 %) were able to fast for the whole month. Age, gender, duration of the disease, its primary origin, associated hypothyroidism, diabetes mellitus, hypertension or diabetes insipidus and daily dose of hydrocortisone did not significantly differ between fasters and non-fasters, full-month-fasters and partial-month-fasters, and fasters with complications and fasters without complications. The frequency of adequate knowledge about the disease was significantly higher in full-month-fasters vs. partial-month-fasters, and in fasters without complications vs. those with complications. In patients with adrenal insufficiency, fasting can cause complications especially if the level of knowledge about the disease is low.
Nakstad, Anders R; Bredmose, Per P; Sandberg, Mårten
2013-07-26
A large number of techniques and devices for cricothyroidotomy have been developed. In this study, the Portex™ Cricothyroidotomy Kit (PCK, Smiths Medical Ltd, Hythe, UK) was compared with the bougie assisted emergency surgical cricothyrotomy technique (BACT). Twenty air ambulance anaesthesiologists performed emergency cricothyrotomy on a cadaveric porcine airway model using both PCK and BACT. Baseline performance and performance after the intensive training package were recorded. Success rate, time to secured airway and tracheal damage were the primary endpoints, and confidence rating was a secondary endpoint. During baseline testing, success rates for PCK and BACT were 60% and 95%, respectively. Tracheal injury rate with PCK was 60% while no such injury was found in BACT. A lecture was given and skills were trained until the participants were able to perform five consecutive successful procedures with both techniques. In the post-training test, all participants were successful with either technique. The mean time to successful insertion was reduced by 15.7 seconds (from 36.3 seconds to 20.6 seconds, p< 0.001) for PCK and by 7.8 seconds (from 44.9 seconds to 37.1 seconds, p=0.021) for BACT. In the post-training scenario, securing the airway with PCK was significantly faster than with BACT (p<0.001). Post-training tracheal laceration occurred in six (30%) of the PCK procedures and in none of the BACT procedures (p=0.028). Testing the base-line PCK skills of prehospital anaesthesiologists revealed low confidence, sub-optimal performance and a very high failure rate. The BACT technique demonstrated a significantly higher success rate and no tracheal damage. In spite of PCK being a significantly faster technique in the post-training test, the anaesthesiologists still reported a higher confidence in BACT. Limitations of the cadaveric porcine airway may have influenced this study because the airway did not challenge the clinicians with realistic tissue bleeding.
Accelerating moderately stiff chemical kinetics in reactive-flow simulations using GPUs
NASA Astrophysics Data System (ADS)
Niemeyer, Kyle E.; Sung, Chih-Jen
2014-01-01
The chemical kinetics ODEs arising from operator-split reactive-flow simulations were solved on GPUs using explicit integration algorithms. Nonstiff chemical kinetics of a hydrogen oxidation mechanism (9 species and 38 irreversible reactions) were computed using the explicit fifth-order Runge-Kutta-Cash-Karp method, and the GPU-accelerated version performed faster than single- and six-core CPU versions by factors of 126 and 25, respectively, for 524,288 ODEs. Moderately stiff kinetics, represented with mechanisms for hydrogen/carbon-monoxide (13 species and 54 irreversible reactions) and methane (53 species and 634 irreversible reactions) oxidation, were computed using the stabilized explicit second-order Runge-Kutta-Chebyshev (RKC) algorithm. The GPU-based RKC implementation demonstrated an increase in performance of nearly 59 and 10 times, for problem sizes consisting of 262,144 ODEs and larger, than the single- and six-core CPU-based RKC algorithms using the hydrogen/carbon-monoxide mechanism. With the methane mechanism, RKC-GPU performed more than 65 and 11 times faster, for problem sizes consisting of 131,072 ODEs and larger, than the single- and six-core RKC-CPU versions, and up to 57 times faster than the six-core CPU-based implicit VODE algorithm on 65,536 ODEs. In the presence of more severe stiffness, such as ethylene oxidation (111 species and 1566 irreversible reactions), RKC-GPU performed more than 17 times faster than RKC-CPU on six cores for 32,768 ODEs and larger, and at best 4.5 times faster than VODE on six CPU cores for 65,536 ODEs. With a larger time step size, RKC-GPU performed at best 2.5 times slower than six-core VODE for 8192 ODEs and larger. Therefore, the need for developing new strategies for integrating stiff chemistry on GPUs was discussed.
Parikh, Mili; Hynan, Linda S; Weiner, Myron F; Lacritz, Laura; Ringe, Wendy; Cullum, C Munro
2014-01-01
Alzheimer disease (AD) characteristically begins with episodic memory impairment followed by other cognitive deficits; however, the course of illness varies, with substantial differences in the rate of cognitive decline. For research and clinical purposes it would be useful to distinguish between persons who will progress slowly from persons who will progress at an average or faster rate. Our objective was to use neurocognitive performance features and disease-specific and health information to determine a predictive model for the rate of cognitive decline in participants with mild AD. We reviewed the records of a series of 96 consecutive participants with mild AD from 1995 to 2011 who had been administered selected neurocognitive tests and clinical measures. Based on Clinical Dementia Rating (CDR) of functional and cognitive decline over 2 years, participants were classified as Faster (n = 45) or Slower (n = 51) Progressors. Stepwise logistic regression analyses using neurocognitive performance features, disease-specific, health, and demographic variables were performed. Neuropsychological scores that distinguished Faster from Slower Progressors included Trail Making Test - A, Digit Symbol, and California Verbal Learning Test (CVLT) Total Learned and Primacy Recall. No disease-specific, health, or demographic variable predicted rate of progression; however, history of heart disease showed a trend. Among the neuropsychological variables, Trail Making Test - A best distinguished Faster from Slower Progressors, with an overall accuracy of 68%. In an omnibus model including neuropsychological, disease-specific, health, and demographic variables, only Trail Making Test - A distinguished between groups. Several neuropsychological performance features were associated with the rate of cognitive decline in mild AD, with baseline Trail Making Test - A performance best separating those who declined at an average or faster rate from those who showed slower progression.
Naming and Categorization in Healthy Participants: Crowded Domains and Blurred Effects of Gender.
Moreno-Martínez, Francisco Javier; Moratilla-Pérez, Iván
2016-09-20
The study of category-specific effects has produced compelling insights into the structure, organization and functioning of cognitive processes. According to some accounts, the greater intra-category structural similarity for living things (LT) contributes to faster access to superordinate pictorial information, making LT easier to classify than structurally dissimilar items (i.e., nonliving things: NLT). Conversely, LT would be harder to name than NLT, as they must compete with within-domain structurally similar items in order to be properly discriminated. Additionally, it has been reported that men perform better with NLT than women, whereas women surpass men with LT but the reasons for this remain unclear. In the current study, we explored both the visual crowding hypothesis and the effects of gender by testing the performance of 40 healthy participants in classification and naming tasks. Analyses revealed that LT were classified significantly faster than NLT (η p 2 = .11), but named significantly slower (η p 2 = .25). Interestingly, the same results persisted after removing atypical categories that are known to distort the interpretation of data from the analyses. Moreover, we did not find the expected effects of gender. Men were more accurate than women naming NLT (η p 2 = .13), and women did not surpass men in any task.
Faster acquisition of laparoscopic skills in virtual reality with haptic feedback and 3D vision.
Hagelsteen, Kristine; Langegård, Anders; Lantz, Adam; Ekelund, Mikael; Anderberg, Magnus; Bergenfelz, Anders
2017-10-01
The study investigated whether 3D vision and haptic feedback in combination in a virtual reality environment leads to more efficient learning of laparoscopic skills in novices. Twenty novices were allocated to two groups. All completed a training course in the LapSim ® virtual reality trainer consisting of four tasks: 'instrument navigation', 'grasping', 'fine dissection' and 'suturing'. The study group performed with haptic feedback and 3D vision and the control group without. Before and after the LapSim ® course, the participants' metrics were recorded when tying a laparoscopic knot in the 2D video box trainer Simball ® Box. The study group completed the training course in 146 (100-291) minutes compared to 215 (175-489) minutes in the control group (p = .002). The number of attempts to reach proficiency was significantly lower. The study group had significantly faster learning of skills in three out of four individual tasks; instrument navigation, grasping and suturing. Using the Simball ® Box, no difference in laparoscopic knot tying after the LapSim ® course was noted when comparing the groups. Laparoscopic training in virtual reality with 3D vision and haptic feedback made training more time efficient and did not negatively affect later video box-performance in 2D. [Formula: see text].
Strength, speed and power characteristics of elite rugby league players.
de Lacey, James; Brughelli, Matt E; McGuigan, Michael R; Hansen, Keir T
2014-08-01
The purpose of this article was to compare strength, speed, and power characteristics between playing position (forwards and backs) in elite rugby league players. A total of 39 first team players (height, 183.8 ± 5.95 cm; body mass, 100.3 ± 10.7 kg; age, 24 ± 3 years) from a National Rugby League club participated in this study. Testing included 10-, 40-m sprint times, sprint mechanics on an instrumented nonmotorized treadmill, and concentric isokinetic hip and knee extension and flexion. Backs, observed to have significantly (p ≤ 0.05) lighter body mass (effect size [ES] = 0.98), were significantly faster (10-m ES = 1.26; 40-m ES = 1.61) and produced significantly greater relative horizontal force and power (ES = 0.87 and 1.04) compared with forwards. However, no significant differences were found between forwards and backs during relative isokinetic knee extension, knee flexion, relative isokinetic hip extension, flexion, prowler sprints, sprint velocity, contact time, or flight time. The findings demonstrate that backs have similar relative strength in comparison with forwards, but run faster overground and produce significantly greater relative horizontal force and power when sprinting on a nonmotorized instrumented treadmill. Developing force and power in the horizontal direction may be beneficial for improving sprint performance in professional rugby league players.
Kinematics of the field hockey penalty corner push-in.
Kerr, Rebecca; Ness, Kevin
2006-01-01
The aims of the study were to determine those variables that significantly affect push-in execution and thereby formulate coaching recommendations specific to the push-in. Two 50 Hz video cameras recorded transverse and longitudinal views of push-in trials performed by eight experienced and nine inexperienced male push-in performers. Video footage was digitized for data analysis of ball speed, stance width, drag distance, drag time, drag speed, centre of massy displacement and segment and stick displacements and velocities. Experienced push-in performers demonstrated a significantly greater (p < 0.05) stance width, a significantly greater distance between the ball and the front foot at the start of the push-in and a significantly faster ball speed than inexperienced performers. In addition, the experienced performers showed a significant positive correlation between ball speed and playing experience and tended to adopt a combination of simultaneous and sequential segment rotation to achieve accuracy and fast ball speed. The study yielded the following coaching recommendations for enhanced push-in performance: maximize drag distance by maximizing front foot-ball distance at the start of the push-in; use a combination of simultaneous and sequential segment rotations to optimise both accuracy and ball speed and maximize drag speed.
High-intensity interval training has positive effects on performance in ice hockey players.
Naimo, M A; de Souza, E O; Wilson, J M; Carpenter, A L; Gilchrist, P; Lowery, R P; Averbuch, B; White, T M; Joy, J
2015-01-01
In spite of the well-known benefits that have been shown, few studies have looked at the practical applications of high-intensity interval training (HIIT) on athletic performance. This study investigated the effects of a HIIT program compared to traditional continuous endurance exercise training. 24 hockey players were randomly assigned to either a continuous or high-intensity interval group during a 4-week training program. The interval group (IG) was involved in a periodized HIIT program. The continuous group (CG) performed moderate intensity cycling for 45-60 min at an intensity that was 65% of their calculated heart rate reserve. Body composition, muscle thickness, anaerobic power, and on-ice measures were assessed pre- and post-training. Muscle thickness was significantly greater in IG (p=0.01) when compared to CG. The IG had greater values for both ∆ peak power (p<0.003) and ∆ mean power (p<0.02). Additionally, IG demonstrated a faster ∆ sprint (p<0.02) and a trend (p=0.08) for faster ∆ endurance test time to completion for IG. These results indicate that hockey players may utilize short-term HIIT to elicit positive effects in muscle thickness, power and on-ice performance. © Georg Thieme Verlag KG Stuttgart · New York.
Images Encryption Method using Steganographic LSB Method, AES and RSA algorithm
NASA Astrophysics Data System (ADS)
Moumen, Abdelkader; Sissaoui, Hocine
2017-03-01
Vulnerability of communication of digital images is an extremely important issue nowadays, particularly when the images are communicated through insecure channels. To improve communication security, many cryptosystems have been presented in the image encryption literature. This paper proposes a novel image encryption technique based on an algorithm that is faster than current methods. The proposed algorithm eliminates the step in which the secrete key is shared during the encryption process. It is formulated based on the symmetric encryption, asymmetric encryption and steganography theories. The image is encrypted using a symmetric algorithm, then, the secret key is encrypted by means of an asymmetrical algorithm and it is hidden in the ciphered image using a least significant bits steganographic scheme. The analysis results show that while enjoying the faster computation, our method performs close to optimal in terms of accuracy.
Graphics performance in rich Internet applications.
Hoetzlein, Rama C
2012-01-01
Rendering performance for rich Internet applications (RIAs) has recently focused on the debate between using Flash and HTML5 for streaming video and gaming on mobile devices. A key area not widely explored, however, is the scalability of raw bitmap graphics performance for RIAs. Does Flash render animated sprites faster than HTML5? How much faster is WebGL than Flash? Answers to these questions are essential for developing large-scale data visualizations, online games, and truly dynamic websites. A new test methodology analyzes graphics performance across RIA frameworks and browsers, revealing specific performance outliers in existing frameworks. The results point toward a future in which all online experiences might be GPU accelerated.
Wu, I-Chien; Chang, Hsing-Yi; Hsu, Chih-Cheng; Chiu, Yen-Feng; Yu, Shu-Han; Tsai, Yi-Fen; Shen, Shi-Chen; Kuo, Ken N; Chen, Ching-Yu; Liu, Kiang; Lee, Marion M; Hsiung, Chao A
2013-01-01
Physical performance is a major determinant of health in older adults, and is related to lifestyle factors. Dietary fiber has multiple health benefits. It remains unclear whether fiber intake is independently linked to superior physical performance. We aimed to assess the association between dietary fiber and physical performance in older adults. This was a cross-sectional study conducted with community-dwelling adults aged 55 years and older (n=2680) from the ongoing Healthy Aging Longitudinal Study (HALST) in Taiwan 2008-2010. Daily dietary fiber intake was assessed using a validated food frequency questionnaire. Physical performance was determined objectively by measuring gait speed, 6-minute walk distance, timed "up and go" (TUG), summary performance score, hand grip strength. Adjusting for all potential confounders, participants with higher fiber intake had significantly faster gait speed, longer 6-minute walk distance, faster TUG, higher summary performance score, and higher hand grip strength (all P <.05). Comparing with the highest quartile of fiber intake, the lowest quartile of fiber intake was significantly associated with the lowest sex-specific quartile of gait speed (adjusted OR, 2.18 in men [95% CI, 1.33-3.55] and 3.65 in women [95% CI, 2.20-6.05]), 6-minute walk distance (OR, 2.40 in men [95% CI, 1.38-4.17] and 4.32 in women [95% CI, 2.37-7.89]), TUG (OR, 2.42 in men [95% CI, 1.43-4.12] and 3.27 in women [95% CI, 1.94-5.52]), summary performance score (OR, 2.12 in men [95% CI, 1.19-3.78] and 5.47 in women [95% CI, 3.20-9.35]), and hand grip strength (OR, 2.64 in men [95% CI, 1.61-4.32] and 4.43 in women [95% CI, 2.62-7.50]). Dietary fiber intake was independently associated with better physical performance.
Asencio, Fernanda de Almeida; Ribeiro, Helizabet Abdala Salomão Ayroza; Romeo, Armando; Wattiez, Arnauld; Ribeiro, Paulo Augusto Galvão Ayroza
2018-05-18
To assess whether the monomanual or bimanual training of laparoscopic suture following the same technique may interfere with the knots' performance time and/or quality. A prospective observational study involving 41 resident students of gynecology/obstetrics and general surgery who attended a laparoscopic suture training for 2 days. The participants were divided into two groups. Group A performed the training using exclusively their dominant hand, and group B performed the training using both hands to tie the intracorporeal knot. All participants followed the same technique, called Romeo Gladiator Rule. At the end of the course, the participants were asked to perform three exercises to assess the time it took them to tie the knots, as well as the quality of the knots. A comparative analysis of the groups showed that there was no statistically significant difference ( p = 0.334) between them regarding the length of time to tie one knot. However, when the time to tie 10 consecutive knots was compared, group A was faster than group B ( p = 0.020). A comparison of the knot loosening average, in millimeters, revealed that the knots made by group B loosened less than those made by group A, but there was no statistically significant difference regarding the number of knots that became untied. This study demonstrated that the knots from group B showed better quality than those from group A, with lower loosening measures and more strength necessary to untie the knots. The study also demonstrated that group A was faster than B when the time to tie ten consecutive knots was compared. Thieme Revinter Publicações Ltda Rio de Janeiro, Brazil.
Chen, Wei-Ying; Wu, Sheng K; Song, Tai-Fen; Chou, Kuei-Ming; Wang, Kuei-Yuan; Chang, Yao-Ching; Goodbourn, Patrick T
2016-12-07
The specific demands of a combat-sport discipline may be reflected in the perceptual-motor performance of its athletes. Taekwondo, which emphasizes kicking, might require faster perceptual processing to compensate for longer latencies to initiate lower-limb movements and to give rapid visual feedback for dynamic postural control, while Karate, which emphasizes both striking with the hands and kicking, might require exceptional eye-hand coordination and fast perceptual processing. In samples of 38 Taekwondo athletes (16 females, 22 males; mean age = 19.9 years, SD = 1.2), 24 Karate athletes (9 females, 15 males; mean age = 18.9 years, SD = 0.9), and 35 Nonathletes (20 females, 15 males; mean age = 20.6 years, SD = 1.5), we measured eye-hand coordination with the Finger-Nose-Finger task, and both perceptual-processing speed and attentional control with the Covert Orienting of Visual Attention (COVAT) task. Eye-hand coordination was significantly better for Karate athletes than for Taekwondo athletes and Nonathletes, but reaction times for the upper extremities in the COVAT task-indicative of perceptual-processing speed-were faster for Taekwondo athletes than for Karate athletes and Nonathletes. In addition, we found no significant difference among groups in attentional control, as indexed by the reaction-time cost of an invalid cue in the COVAT task. The results suggest that athletes in different combat sports exhibit distinct profiles of perceptual-motor performance. © The Author(s) 2016.
A comparison of caffeine versus pseudoephedrine on cycling time-trial performance.
Spence, Angela L; Sim, Marc; Landers, Grant; Peeling, Peter
2013-10-01
Both caffeine (CAF) and pseudoephedrine (PSE) are proposed to be central nervous system stimulants. However, during competition, CAF is a permitted substance, whereas PSE is a banned substance at urinary levels >150 μg · ml(-1). As a result, this study aimed to compare the effect of CAF versus PSE use on cycling time trial (TT) performance to explore whether the legal stimulant was any less ergogenic than the banned substance. Here, 10 well-trained male cyclists or triathletes were recruited for participation. All athletes were required to attend the laboratory on four separate occasions--including a familiarization trial and three experimental trials, which required participants to complete a simulated 40 km (1,200 kJ) cycling TT after the ingestion of either 200 mg CAF, 180 mg PSE or a nonnutritive placebo (PLA). The results showed that the total time taken and the mean power produced during each TT was not significantly different (p > .05) between trials, despite a 1.3% faster overall time (~57 s) after CAF consumption. Interestingly, the time taken to complete the second half of the TT was significantly faster (p < .05) in CAF as compared with PSE (by 99 s), with magnitude based inferences suggesting a 91% beneficial effect of CAF during the second half of the TT. This investigation further confirms the ergogenic benefits of CAF use during TT performances and further suggests this legal CNS stimulant has a better influence than a supra-therapeutic dose of PSE.
A novel one-shot circular stapler closure for atrial septal defect in a beating-heart porcine model.
Tarui, Tatsuya; Tomita, Shigeyuki; Ishikawa, Norihiko; Ohtake, Hiroshi; Watanabe, Go
2015-02-01
In surgical atrial septal defect (ASD) closure, there are no techniques or devices that can close the ASD accurately in a short time under a beating heart. We have developed a simple and automatic ASD closure technique using a circular stapler. This study assessed the feasibility and efficacy of a new circular stapler closure for ASD. Under a continuous beating heart, hand-sewn patch plasty ASD closure was performed in 6 pigs (group A) and circular stapler ASD closure was performed in 6 pigs (group B). The time to close the ASD and the effectiveness of the closure were compared. Closure was significantly faster in group B (10.5 ± 1.0 seconds) than in group A (664 ± 10 seconds; p < 0.05). There was no leakage at the closure site, and sufficient tolerance was confirmed. A circular stapler can be used to treat ASD faster than hand-sewn patch plasty, with sufficient pressure tolerance in a beating heart porcine model. Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.
Mathieu, Chantal; Bode, Bruce W; Franek, Edward; Philis-Tsimikas, Athena; Rose, Ludger; Graungaard, Tina; Birk Østerskov, Anne; Russell-Jones, David
2018-05-01
To compare the safety and efficacy of fast-acting insulin aspart (faster aspart) with conventional insulin aspart (IAsp) in adults with type 1 diabetes (T1D). onset 1 was a randomized, multicentre, treat-to-target, phase III, 52-week (initial 26 weeks + additional 26 weeks) trial conducted at 165 sites across 9 countries. Adults with T1D were randomly allocated to double-blind mealtime faster aspart or IAsp, each with once- or twice-daily insulin detemir. The primary endpoint, change in glycated haemoglobin (HbA1c) from baseline after the initial 26 weeks, has been reported previously. In the present paper, we report data from the full 52-week study period. Between August 2013 and June 2015, 381 participants were assigned to double-blind faster aspart and 380 participants to IAsp. After 52 weeks, estimated mean changes from baseline in HbA1c levels were -0.08% (faster aspart) and +0.01% (IAsp); estimated treatment difference significantly favoured faster aspart (-0.10% [95% confidence interval {CI} -0.19;-0.00]; P = .0424). Changes from baseline in 1-hour postprandial plasma glucose (PPG) increment (meal test; faster aspart -1.05 mmol/L; IAsp -0.14 mmol/L) also significantly favoured faster aspart (estimated treatment difference -0.91 mmol/L [95% CI -1.40;-0.43]; -16.48 mg/dL [95% CI -25.17;-7.80]; P = .0002). There was no difference in overall severe or blood glucose-confirmed hypoglycaemic episodes or treatment-emergent adverse events between treatments. At 52 weeks, overall glycaemic control had significantly improved with faster aspart vs IAsp, consistent with the 26-week study findings. Achieving an insulin profile closer to physiological insulin secretion with faster aspart translates into lower PPG and HbA1c levels compared with those achieved with IAsp in people with T1D. © 2018 The Authors. Diabetes, Obesity and Metabolism published by John Wiley & Sons Ltd.
Analysis of the faster-than-Nyquist optimal linear multicarrier system
NASA Astrophysics Data System (ADS)
Marquet, Alexandre; Siclet, Cyrille; Roque, Damien
2017-02-01
Faster-than-Nyquist signalization enables a better spectral efficiency at the expense of an increased computational complexity. Regarding multicarrier communications, previous work mainly relied on the study of non-linear systems exploiting coding and/or equalization techniques, with no particular optimization of the linear part of the system. In this article, we analyze the performance of the optimal linear multicarrier system when used together with non-linear receiving structures (iterative decoding and direct feedback equalization), or in a standalone fashion. We also investigate the limits of the normality assumption of the interference, used for implementing such non-linear systems. The use of this optimal linear system leads to a closed-form expression of the bit-error probability that can be used to predict the performance and help the design of coded systems. Our work also highlights the great performance/complexity trade-off offered by decision feedback equalization in a faster-than-Nyquist context. xml:lang="fr"
Elbin, R J; Beatty, Amanda; Covassin, Tracey; Schatz, Philip; Hydeman, Ana; Kontos, Anthony P
2015-01-01
This study compared changes in neurocognitive performance and symptom reports following an acute bout of soccer heading among athletes with and without protective soccer headgear. A total of 25 participants headed a soccer ball 15 times over a 15-minute period, using a proper linear heading technique. Participants in the experimental group completed the heading exercise while wearing a protective soccer headband and controls performed the heading exercise without wearing the soccer headband. Neurocognitive performance and symptom reports were assessed before and after the acute bout of heading. Participants wearing the headband showed significant decreases on verbal memory (p = 0.02) compared with the no headband group, while the no headband group demonstrated significantly faster reaction time (p = 0.03) than the headband group following the heading exercise. These findings suggest that protective soccer headgear likely does not mitigate the subtle neurocognitive effects of acute soccer heading.
Large-scale seismic waveform quality metric calculation using Hadoop
NASA Astrophysics Data System (ADS)
Magana-Zook, S.; Gaylord, J. M.; Knapp, D. R.; Dodge, D. A.; Ruppert, S. D.
2016-09-01
In this work we investigated the suitability of Hadoop MapReduce and Apache Spark for large-scale computation of seismic waveform quality metrics by comparing their performance with that of a traditional distributed implementation. The Incorporated Research Institutions for Seismology (IRIS) Data Management Center (DMC) provided 43 terabytes of broadband waveform data of which 5.1 TB of data were processed with the traditional architecture, and the full 43 TB were processed using MapReduce and Spark. Maximum performance of 0.56 terabytes per hour was achieved using all 5 nodes of the traditional implementation. We noted that I/O dominated processing, and that I/O performance was deteriorating with the addition of the 5th node. Data collected from this experiment provided the baseline against which the Hadoop results were compared. Next, we processed the full 43 TB dataset using both MapReduce and Apache Spark on our 18-node Hadoop cluster. These experiments were conducted multiple times with various subsets of the data so that we could build models to predict performance as a function of dataset size. We found that both MapReduce and Spark significantly outperformed the traditional reference implementation. At a dataset size of 5.1 terabytes, both Spark and MapReduce were about 15 times faster than the reference implementation. Furthermore, our performance models predict that for a dataset of 350 terabytes, Spark running on a 100-node cluster would be about 265 times faster than the reference implementation. We do not expect that the reference implementation deployed on a 100-node cluster would perform significantly better than on the 5-node cluster because the I/O performance cannot be made to scale. Finally, we note that although Big Data technologies clearly provide a way to process seismic waveform datasets in a high-performance and scalable manner, the technology is still rapidly changing, requires a high degree of investment in personnel, and will likely require significant changes in other parts of our infrastructure. Nevertheless, we anticipate that as the technology matures and third-party tool vendors make it easier to manage and operate clusters, Hadoop (or a successor) will play a large role in our seismic data processing.
Physical performance and positional differences among young female volleyball players.
Paz, Gabriel A; Gabbett, Tim J; Maia, Marianna F; Santana, Haroldo; Miranda, Humberto; Lima, Vicente
2017-10-01
The purpose of this study was to investigate the association among anthropometric, physical performance parameters, and dynamic postural control attributes of young female volleyball athletes, and to determine if differences exist in these attributes according to playing position. Forty-three young female volleyball players participated in this study. Players were divided by position into hitters (N.=17), middle blockers (N.=8), setters (N.=10), and liberos (N.=8). Stature, body mass, vertical jump (VJ), peak power, horizontal jump (HJ), sit-and-reach (SRT), star excursion balance (SEBT), and agility (e.g. shuttle run and Illinois agility test) tests were assessed on non-consecutive days in randomized order. No difference was found between groups for SRT, peak power, VJ, and HJ (P≤0.05). Middle blockers and hitters were taller than setters (P≤0.05). Middle blockers were also taller than liberos (P=0.017). Significant differences were observed among groups for agility tests, with hitters significantly faster than setters (P=0.023) and middle blockers (P=0.037). In addition, liberos were significantly faster than setters (P=0.032) and middle blockers (P=0.046), during the Illinois agility test. No difference was observed between groups for reach distance scores in the SEBT. These results demonstrate important positional differences in agility measures of young female volleyball players. Coaches can use this information to determine the type of physical profile that is needed for specific positions and to design training programs to maximize strength, power, and neuromuscular development of young female volleyball athletes.
Speed and countermovement-jump characteristics of elite female soccer players, 1995-2010.
Haugen, Thomas A; Tønnessen, Espen; Seiler, Stephen
2012-12-01
The purpose of this investigation was to compare sprint and countermovement-jump (CMJ) performance among female competitive soccer players as a function of performance level, field position, and age. In addition, the authors wanted to quantify the evolution of these physical characteristics among elite players over a 15-y period. 194 female elite players (22± 4.1 y, 63 ± 5.6 kg), including an Olympic winning squad, tested 40-m sprint with electronic timing and CMJ on a force platform at the Norwegian Olympic training center from 1995 to 2010. Moderate to large velocity differences across performance levels and positions were observed. National-team players were 2% faster than 1st-division players (P = .027, d = 0.5) and 5% faster than 2nd-division players (P < .001, d = 1.3) over 0-20 m. National-team players jumped 8-9% higher than 1st-division players (P = .001, d = 0.6) and junior elite players (P = .023, d = 0.5). Forwards were 3-4% faster than midfielders (P < .001, d = 0.8) and goalkeepers (P = .003, d = 0.9) over 0-20 m. No differences in velocity or CMJ height were observed among the age categories. Players from 2006-2010 were 2% faster (P < .05, d = 0.6) than players from 1995-1999 over 20 m, whereas no differences in 20- to 40-m velocity or CMJ performance were observed. This study provides effect-magnitude estimates for the influence of performance level, age, and player position on sprint and CMJ performance in female soccer players. While 20- to 40-m velocity and CMJ performance have remained stable over the time, there has been a moderate but positive development in 0- to 20-m velocity among elite performers.
Articulation rate across dialect, age, and gender
Jacewicz, Ewa; Fox, Robert A.; O’Neill, Caitlin; Salmons, Joseph
2009-01-01
The understanding of sociolinguistic variation is growing rapidly, but basic gaps still remain. Whether some languages or dialects are spoken faster or slower than others constitutes such a gap. Speech tempo is interconnected with social, physical and psychological markings of speech. This study examines regional variation in articulation rate and its manifestations across speaker age, gender and speaking situations (reading vs. free conversation). The results of an experimental investigation show that articulation rate differs significantly between two regional varieties of American English examined here. A group of Northern speakers (from Wisconsin) spoke significantly faster than a group of Southern speakers (from North Carolina). With regard to age and gender, young adults read faster than older adults in both regions; in free speech, only Northern young adults spoke faster than older adults. Effects of gender were smaller and less consistent; men generally spoke slightly faster than women. As the body of work on the sociophonetics of American English continues to grow in scope and depth, we argue that it is important to include fundamental phonetic information as part of our catalog of regional differences and patterns of change in American English. PMID:20161445
Do Running Kinematic Characteristics Change over a Typical HIIT for Endurance Runners?
García-Pinillos, Felipe; Soto-Hermoso, Víctor M; Latorre-Román, Pedro Á
2016-10-01
García-Pinillos, F, Soto-Hermoso, VM, and Latorre-Román, PÁ. Do running kinematic characteristics change over a typical HIIT for endurance runners?. J Strength Cond Res 30(10): 2907-2917, 2016-The purpose of this study was to describe kinematic changes that occur during a common high-intensity intermittent training (HIIT) session for endurance runners. Twenty-eight male endurance runners participated in this study. A high-speed camera was used to measure sagittal-plane kinematics at the first and the last run during a HIIT (4 × 3 × 400 m). The dependent variables were spatial-temporal variables, joint angles during support and swing, and foot strike pattern. Physiological variables, rate of perceived exertion, and athletic performance were also recorded. No significant changes (p ≥ 0.05) in kinematic variables were found during the HIIT session. Two cluster analyses were performed, according to the average running pace-faster vs. slower, and according to exhaustion level reached-exhausted group vs. nonexhausted group (NEG). At first run, no significant differences were found between groups. As for the changes induced by the running protocol, significant differences (p ≤ 0.05) were found between faster and slower athletes at toe-off in θhip and θknee, whereas some changes were found in NEG in θhip during toe-off (+4.3°) and θknee at toe-off (-5.2°) during swing. The results show that a common HIIT session for endurance runners did not consistently or substantially perturb the running kinematics of trained male runners. Additionally, although some differences between groups have been found, neither athletic performance nor exhaustion level reached seems to be determinant in the kinematic response during a HIIT, at least for this group of moderately trained endurance runners.
Sequence-based heuristics for faster annotation of non-coding RNA families.
Weinberg, Zasha; Ruzzo, Walter L
2006-01-01
Non-coding RNAs (ncRNAs) are functional RNA molecules that do not code for proteins. Covariance Models (CMs) are a useful statistical tool to find new members of an ncRNA gene family in a large genome database, using both sequence and, importantly, RNA secondary structure information. Unfortunately, CM searches are extremely slow. Previously, we created rigorous filters, which provably sacrifice none of a CM's accuracy, while making searches significantly faster for virtually all ncRNA families. However, these rigorous filters make searches slower than heuristics could be. In this paper we introduce profile HMM-based heuristic filters. We show that their accuracy is usually superior to heuristics based on BLAST. Moreover, we compared our heuristics with those used in tRNAscan-SE, whose heuristics incorporate a significant amount of work specific to tRNAs, where our heuristics are generic to any ncRNA. Performance was roughly comparable, so we expect that our heuristics provide a high-quality solution that--unlike family-specific solutions--can scale to hundreds of ncRNA families. The source code is available under GNU Public License at the supplementary web site.
Aerobic Capacity is Related to Repeated Sprint Ability with Sprint Distances Less Than 40 Meters
SANDERS, GABRIEL J.; TURNER, ZACHARY; BOOS, BRIAN; PEACOCK, COREY A.; PEVELER, WILLARD; LIPPING, ALAR
2017-01-01
Research is inconclusive regarding the association between aerobic fitness (objectively measured VO2max) and repeated sprint performance when the sprints are less than 40 meters. Soccer athletes must be able to repeat sprints without significant decreases in speed and strength and conditioning coaches need to better understand if aerobic fitness is related to repeated sprint ability (RSA). Twenty (10 male, 10 female) Division I soccer athletes first completed a graded maximal treadmill test to measure VO2max. Then on a separate day, athletes completed the RSA test. The RSA test consisted of 10, 30-meter sprints which athletes repeated every 30 seconds. There were significant negative correlations (r ≤ −0.69, P < 0.001) between VO2max and all 10-sprint times and average sprint time. More aerobically fit Division I soccer athletes were faster at all time points during the RSA test. Aerobic fitness is associated with faster sprint times during a more anaerobic RSA test when sprint distances are less than 40 meters. PMID:28344734
Differences in In Vitro Disintegration Time among Canadian Brand and Generic Bisphosphonates
Olszynski, Wojciech P.; Adachi, Jonathan D.; Davison, K. Shawn
2014-01-01
The objective of this study was to compare the disintegration times among Canadian-marketed brand (alendronate 70 mg, alendronate 70 mg plus vitamin D 5600 IU, and risedronate 35 mg) and generic (Novo-alendronate 70 mg and Apo-alendronate 70 mg) once-weekly dosed bisphosphonates. All disintegration tests were performed with a Vanderkamp Disintegration Tester. Disintegration was deemed to have occurred when no residue of the tablet, except fragments of insoluble coating or capsule shell, was visible. Eighteen to 20 samples were tested for each bisphosphonate group. The mean (±standard deviation) disintegration times were significantly (P < 0.05) faster for Apo-alendronate (26 ± 5.6 seconds) and Novo-alendronate (13 ± 1.1 seconds) as compared to brand alendronate (147 ± 50.5 seconds), brand alendronate plus vitamin D (378 ± 60.5 seconds), or brand risedronate (101 ± 20.6 seconds). The significantly faster disintegration of the generic tablets as compared to the brand bisphosphonates may have concerning safety and effectiveness implications for patients administering these therapies. PMID:25349772
Differences in In Vitro Disintegration Time among Canadian Brand and Generic Bisphosphonates.
Olszynski, Wojciech P; Adachi, Jonathan D; Davison, K Shawn
2014-01-01
The objective of this study was to compare the disintegration times among Canadian-marketed brand (alendronate 70 mg, alendronate 70 mg plus vitamin D 5600 IU, and risedronate 35 mg) and generic (Novo-alendronate 70 mg and Apo-alendronate 70 mg) once-weekly dosed bisphosphonates. All disintegration tests were performed with a Vanderkamp Disintegration Tester. Disintegration was deemed to have occurred when no residue of the tablet, except fragments of insoluble coating or capsule shell, was visible. Eighteen to 20 samples were tested for each bisphosphonate group. The mean (±standard deviation) disintegration times were significantly (P < 0.05) faster for Apo-alendronate (26 ± 5.6 seconds) and Novo-alendronate (13 ± 1.1 seconds) as compared to brand alendronate (147 ± 50.5 seconds), brand alendronate plus vitamin D (378 ± 60.5 seconds), or brand risedronate (101 ± 20.6 seconds). The significantly faster disintegration of the generic tablets as compared to the brand bisphosphonates may have concerning safety and effectiveness implications for patients administering these therapies.
Rejman, Marek; Wiesner, Wojciech; Silakiewicz, Piotr; Klarowicz, Andrzej; Abraldes, J. Arturo
2012-01-01
The aim of this study was an analysis of the time required to swim to a victim and tow them back to shore, while perfoming the flutter-kick and the dolphin-kick using fins. It has been hypothesized that using fins while using the dolphin-kick when swimming leads to reduced rescue time. Sixteen lifeguards took part in the study. The main tasks performed by them, were to approach and tow (double armpit) a dummy a distance of 50m while applying either the flutter-kick, or the dolphin-kick with fins. The analysis of the temporal parameters of both techniques of kicking demonstrates that, during the approach to the victim, neither the dolphin (tmean = 32.9s) or the flutter kick (tmean = 33.0s) were significantly faster than the other. However, when used for towing a victim the flutter kick (tmean = 47.1s) was significantly faster when compared to the dolphin-kick (tmean = 52.8s). An assessment of the level of technical skills in competitive swimming, and in approaching and towing the victim, were also conducted. Towing time was significantly correlated with the parameter that linked the temporal and technical dimensions of towing and swimming (difference between flutter kick towing time and dolphin-kick towing time, 100m medley time and the four swimming strokes evaluation). No similar interdependency has been discovered in flutter kick towing time. These findings suggest that the dolphin-kick is a more difficult skill to perform when towing the victim than the flutter-kick. Since the hypothesis stated was not confirmed, postulates were formulated on how to improve dolphin-kick technique with fins, in order to reduce swimming rescue time. Key points The source of reduction of swimming rescue time was researched. Time required to approach and to tow the victim while doing the flutter kick and the dolphin-kick with fins was analyzed. The propulsion generated by dolphin-kick did not make the approach and tow faster than the flutter kick. More difficult skill to realize of dolphin-kick than the flutter-kick was postulated. The criteria for how improve dolphin kick technique with fins were formulated. PMID:24150079
Tyner, Bryan C; Fienup, Daniel M
2015-09-01
Graphing is socially significant for behavior analysts; however, graphing can be difficult to learn. Video modeling (VM) may be a useful instructional method but lacks evidence for effective teaching of computer skills. A between-groups design compared the effects of VM, text-based instruction, and no instruction on graphing performance. Participants who used VM constructed graphs significantly faster and with fewer errors than those who used text-based instruction or no instruction. Implications for instruction are discussed. © Society for the Experimental Analysis of Behavior.
Laparoscopic skills assessment: an additional modality for pediatric surgery fellowship selection.
Hazboun, Rajaie; Rodriguez, Samuel; Thirumoorthi, Arul; Baerg, Joanne; Moores, Donald; Tagge, Edward P
2017-12-01
The Pediatric Surgery fellow selection is a multi-layered process which has not included assessment of surgical dexterity. Data was collected prospectively as part of the 2016 Pediatric Surgery Match interview process. Applicants completed a questionnaire to document laparoscopic experience and fine motor skills activities. Actual laparoscopic skills were assessed using a simulator. Time to complete an intracorporeal knot was tabulated. An initial rank list was formulated based only on the ERAS application and interview scores. The rank list was re-formulated following the laparoscopic assessment. Un-paired T-test and regression were utilized to analyze the data. Forty applicants were interviewed with 18 matched (45%). The mean knot tying time was 201.31s for matched and 202.35s for unmatched applicants. Playing a musical instrument correlated with faster knot tying (p=0.03). No correlation was identified between knot tying time and either video game experience (p=0.4) or passing the FLS exam (p=0.78). Laparoscopic skills assessment lead to significant reordering of rank list (p=0.01). Laparoscopic skills performance significantly impacted ranking. Playing a musical instrument correlated with faster knot tying. No correlation was identified between laparoscopic performance and passing the FLS exam or other activities traditionally believed to improve technical ability. Prospective study. Level II. Copyright © 2017 Elsevier Inc. All rights reserved.
A female advantage in the serial production of non-representational learned gestures.
Chipman, Karen; Hampson, Elizabeth
2006-01-01
Clinical research has demonstrated a sex difference in the neuroanatomical organization of the limb praxis system. To test for a corresponding sex difference in the functioning of this system, we compared healthy men and women on a gesture production task modeled after those used in apraxia research. In two separate studies, participants were taught to perform nine non-representational gestures in response to computer-generated color cues. After extensive practice with the gestures, the color cues were placed on a timer and presented in randomized sequences at progressively faster speeds. A detailed videotape analysis revealed that women in both studies committed significantly fewer 'praxic' errors than men (i.e., errors that resembled those seen in limb apraxia). This was true during both the untimed practice trials and the speeded trials of the task, despite equivalent numbers of errors between the sexes in the 'non-praxic' (i.e., executory) error categories. Women in both studies also performed the task at significantly faster speeds than men. This finding was not accounted for by a female advantage in extraneous elements of the task, i.e., speed of color processing, associative retrieval, or motor execution. Together, the two studies provide convergent support for a female advantage in the efficiency of forelimb gesture production. They are consistent with emerging evidence of a sex difference in the anatomical organization of the praxis system.
Porter, Jared M.; Nolan, Russell P.; Ostrowski, Erik J.; Wulf, Gabriele
2010-01-01
The primary purpose of this study was to investigate if focusing attention externally produced faster movement times compared to instructions that focused attention internally or a control set of instructions that did not explicitly focus attention when performing an agility task. A second purpose of the study was to measure participants’ focus of attention during practice by use of a questionnaire. Participants (N = 20) completed 15 trials of an agility “L” run following instructions designed to induce an external (EXT), internal (INT) attentional focus or a control (CON) set of instructions inducing no specific focus of attention. Analysis revealed when participants followed the EXT instructions they had significantly faster movement times compared to when they followed the INT and CON set of instructions; consistent with previous research the INT and CON movement times were not significantly different from each other. Qualitative data showed when participants were in the external condition they focused externally 67% of the time. When they were in the internal condition they focused internally 76% of the time, and when they were in the control condition they did not use an internal or external focus of attention 77% of the time. Qualitative data also revealed participants in the EXT, INT, and CON conditions switched their focus of attention at a frequency of 27, 35, and 51% respectively. PMID:21833271
Cousin, Emilie; Perrone, Marcela; Baciu, Monica
2009-04-01
This behavioral study aimed at assessing the effect of two variables on the degree of hemispheric specialization for language. One of them was the grapho-phonemic translation (transformation) (letter-sound mapping) and the other was the participants'gender. The experiment was conducted with healthy volunteers. A divided visual field procedure has been used to perform a phoneme detection task implying either regular (transparent) grapho-phonemic translation (letter-sound mapping consistency) or irregular (non-transparent) grapho-phonemic translation (letter-sound mapping inconsistency). Our results reveal a significant effect of grapho-phonemic translation on the degree of hemispheric dominance for language. The phoneme detection on items with transparent translation (TT) was performed faster than phoneme detection on items with non-transparent translation (NTT). This effect seems to be due to faster identification of TT than NTT when the items were presented in the left visual field (LVF)-right hemisphere (RH). There was no difference between TT and NTT for stimuli presented in the right visual field (RVF)-left hemisphere (LH). This result suggests that grapho-phonemic translation or the degree of transparency can affect the degree of hemispheric specialization, by modulating the right hemisphere activity. With respect to gender, male participants were significantly more lateralized than female participants but no interaction was observed between gender and degree of transparency.
Corneal wound healing promoted by 3 blood derivatives: an in vitro and in vivo comparative study.
Freire, Vanesa; Andollo, Noelia; Etxebarria, Jaime; Hernáez-Moya, Raquel; Durán, Juan A; Morales, María-Celia
2014-06-01
The aim of this study was to compare the effect on corneal wound healing of 3 differently manufactured blood derivatives [autologous serum (AS), platelet-rich plasma, and serum derived from plasma rich in growth factors (s-PRGF)]. Scratch wound-healing assays were performed on rabbit primary corneal epithelial cultures and human corneal epithelial cells. Additionally, mechanical debridement of rabbit corneal epithelium was performed. Wound-healing progression was assessed by measuring the denuded areas remaining over time after treatment with each of the 3 blood derivatives or a control treatment. In vitro data show statistically significant differences in the healing process with all the derivatives compared with the control, but 2 of them (AS and s-PRGF) induced markedly faster wound healing. In contrast, although the mean time required to complete in vivo reepithelization was similar to that of AS and s-PRGF treatment, only wounds treated with s-PRGF were significantly smaller in size from 2.5 days onward with respect to the control treatment. All 3 blood derivatives studied are promoters of corneal reepithelization. However, the corneal wound-healing progresses differently with each derivative, being faster in vitro under AS and s-PRGF treatment and producing in vivo the greatest decrease in wound size under s-PRGF treatment. These findings highlight that the manufacturing process of the blood derivatives may modulate the efficacy of the final product.
Sakamoto, Akihiro; Sinclair, Peter J
2006-08-01
This study investigated the effect of movement velocity on the relationship between loading intensity and the number of repetitions of bench press. Thirteen healthy men (age = 21.7 +/- 1.0 years; weight = 76.8 +/- 2.5 kg; 1 repetition maximum [1RM] = 99.5 +/- 6.0 kg), who were involved in regular weight training, voluntarily participated in the experiment. Subjects performed bench presses on a Smith machine at 5 different intensities (40-80% 1RM), repeated for 4 velocity conditions (slow: 0.15 +/- 0.03 m.s(-1); medium: 0.32 +/- 0.07 m.s(-1); fast: 0.52 +/- 0.12 m.s(-1); ballistic: maximum velocity), which were randomly assigned over 5 experimental sessions after a 1RM test. Velocity significantly changed the relationship between intensity (%1RM) and the number of reps performed (p < 0.001), with faster velocities producing a higher number of reps. A significant interaction between intensity and velocity meant that velocity had a much greater effect on repetitions at lower intensities. These results suggest that the benefits of using a stretch-shortening cycle during faster movements outweigh the associated disadvantages from the force-velocity relationship. The practical applications of this study are that, when trainees are assigned a resistance training with specific RM values, the lifted intensity (%1RM) or weights will not be consistent unless velocity is controlled during training.
Mihalik, Jason P; Libby, Jeremiah J; Battaglini, Claudio L; McMurray, Robert G
2008-01-01
The purpose of this study was to determine whether there were differences in vertical jump height and lower body power production gains between complex and compound training programs. A secondary purpose was to determine whether differences in gains were observed at a faster rate between complex and compound training programs. Thirty-one college-aged club volleyball players (11 men and 20 women) were assigned into either a complex training group or a compound training group based on gender and pre-training performance measures. Both groups trained twice per week for 4 weeks. Work was equated between the 2 groups. Complex training alternated between resistance and plyometric exercises on each training day; whereas, compound training consisted of resistance training on one day and plyometric training on the other. Our analyses showed significant improvements in vertical jump height in both training groups after only 3 weeks of training (P < 0.0001); vertical jump height increased by approximately 5% and 9% in the complex and compound training groups, respectively. However, neither group improved significantly better than the other, nor did either group experience faster gains in vertical leap or power output. The results of this study suggest that performing a minimum of 3 weeks of either complex or compound training is effective for improving vertical jump height and power output; thus, coaches should choose the program which best suits their training schedules.
The impact of video games on training surgeons in the 21st century.
Rosser, James C; Lynch, Paul J; Cuddihy, Laurie; Gentile, Douglas A; Klonsky, Jonathan; Merrell, Ronald
2007-02-01
Video games have become extensively integrated into popular culture. Anecdotal observations of young surgeons suggest that video game play contributes to performance excellence in laparoscopic surgery. Training benefits for surgeons who play video games should be quantifiable. There is a potential link between video game play and laparoscopic surgical skill and suturing. Cross-sectional analysis of the performance of surgical residents and attending physicians participating in the Rosser Top Gun Laparoscopic Skills and Suturing Program (Top Gun). Three different video game exercises were performed, and surveys were completed to assess past experience with video games and current level of play, and each subject's level of surgical training, number of laparoscopic cases performed, and number of years in medical practice. Academic medical center and surgical training program. Thirty-three residents and attending physicians participating in Top Gun from May 10 to August 24, 2002. The primary outcome measures were compared between participants' laparoscopic skills and suturing capability, video game scores, and video game experience. Past video game play in excess of 3 h/wk correlated with 37% fewer errors (P<.02) and 27% faster completion (P<.03). Overall Top Gun score (time and errors) was 33% better (P<.005) for video game players and 42% better (P<.01) if they played more than 3 h/wk. Current video game players made 32% fewer errors (P=.04), performed 24% faster (P<.04), and scored 26% better overall (time and errors) (P<.005) than their nonplaying colleagues. When comparing demonstrated video gaming skills, those in the top tertile made 47% fewer errors, performed 39% faster, and scored 41% better (P<.001 for all) on the overall Top Gun score. Regression analysis also indicated that video game skill and past video game experience are significant predictors of demonstrated laparoscopic skills. Video game skill correlates with laparoscopic surgical skills. Training curricula that include video games may help thin the technical interface between surgeons and screen-mediated applications, such as laparoscopic surgery. Video games may be a practical teaching tool to help train surgeons.
A fast least-squares algorithm for population inference
2013-01-01
Background Population inference is an important problem in genetics used to remove population stratification in genome-wide association studies and to detect migration patterns or shared ancestry. An individual’s genotype can be modeled as a probabilistic function of ancestral population memberships, Q, and the allele frequencies in those populations, P. The parameters, P and Q, of this binomial likelihood model can be inferred using slow sampling methods such as Markov Chain Monte Carlo methods or faster gradient based approaches such as sequential quadratic programming. This paper proposes a least-squares simplification of the binomial likelihood model motivated by a Euclidean interpretation of the genotype feature space. This results in a faster algorithm that easily incorporates the degree of admixture within the sample of individuals and improves estimates without requiring trial-and-error tuning. Results We show that the expected value of the least-squares solution across all possible genotype datasets is equal to the true solution when part of the problem has been solved, and that the variance of the solution approaches zero as its size increases. The Least-squares algorithm performs nearly as well as Admixture for these theoretical scenarios. We compare least-squares, Admixture, and FRAPPE for a variety of problem sizes and difficulties. For particularly hard problems with a large number of populations, small number of samples, or greater degree of admixture, least-squares performs better than the other methods. On simulated mixtures of real population allele frequencies from the HapMap project, Admixture estimates sparsely mixed individuals better than Least-squares. The least-squares approach, however, performs within 1.5% of the Admixture error. On individual genotypes from the HapMap project, Admixture and least-squares perform qualitatively similarly and within 1.2% of each other. Significantly, the least-squares approach nearly always converges 1.5- to 6-times faster. Conclusions The computational advantage of the least-squares approach along with its good estimation performance warrants further research, especially for very large datasets. As problem sizes increase, the difference in estimation performance between all algorithms decreases. In addition, when prior information is known, the least-squares approach easily incorporates the expected degree of admixture to improve the estimate. PMID:23343408
A fast least-squares algorithm for population inference.
Parry, R Mitchell; Wang, May D
2013-01-23
Population inference is an important problem in genetics used to remove population stratification in genome-wide association studies and to detect migration patterns or shared ancestry. An individual's genotype can be modeled as a probabilistic function of ancestral population memberships, Q, and the allele frequencies in those populations, P. The parameters, P and Q, of this binomial likelihood model can be inferred using slow sampling methods such as Markov Chain Monte Carlo methods or faster gradient based approaches such as sequential quadratic programming. This paper proposes a least-squares simplification of the binomial likelihood model motivated by a Euclidean interpretation of the genotype feature space. This results in a faster algorithm that easily incorporates the degree of admixture within the sample of individuals and improves estimates without requiring trial-and-error tuning. We show that the expected value of the least-squares solution across all possible genotype datasets is equal to the true solution when part of the problem has been solved, and that the variance of the solution approaches zero as its size increases. The Least-squares algorithm performs nearly as well as Admixture for these theoretical scenarios. We compare least-squares, Admixture, and FRAPPE for a variety of problem sizes and difficulties. For particularly hard problems with a large number of populations, small number of samples, or greater degree of admixture, least-squares performs better than the other methods. On simulated mixtures of real population allele frequencies from the HapMap project, Admixture estimates sparsely mixed individuals better than Least-squares. The least-squares approach, however, performs within 1.5% of the Admixture error. On individual genotypes from the HapMap project, Admixture and least-squares perform qualitatively similarly and within 1.2% of each other. Significantly, the least-squares approach nearly always converges 1.5- to 6-times faster. The computational advantage of the least-squares approach along with its good estimation performance warrants further research, especially for very large datasets. As problem sizes increase, the difference in estimation performance between all algorithms decreases. In addition, when prior information is known, the least-squares approach easily incorporates the expected degree of admixture to improve the estimate.
Effects of music tempo upon submaximal cycling performance.
Waterhouse, J; Hudson, P; Edwards, B
2010-08-01
In an in vivo laboratory controlled study, 12 healthy male students cycled at self-chosen work-rates while listening to a program of six popular music tracks of different tempi. The program lasted about 25 min and was performed on three occasions--unknown to the participants, its tempo was normal, increased by 10% or decreased by 10%. Work done, distance covered and cadence were measured at the end of each track, as were heart rate and subjective measures of exertion, thermal comfort and how much the music was liked. Speeding up the music program increased distance covered/unit time, power and pedal cadence by 2.1%, 3.5% and 0.7%, respectively; slowing the program produced falls of 3.8%, 9.8% and 5.9%. Average heart rate changes were +0.1% (faster program) and -2.2% (slower program). Perceived exertion and how much the music was liked increased (faster program) by 2.4% and 1.3%, respectively, and decreased (slower program) by 3.6% and 35.4%. That is, healthy individuals performing submaximal exercise not only worked harder with faster music but also chose to do so and enjoyed the music more when it was played at a faster tempo. Implications of these findings for improving training regimens are discussed.
Music experience influences laparoscopic skills performance.
Boyd, Tanner; Jung, Inkyung; Van Sickle, Kent; Schwesinger, Wayne; Michalek, Joel; Bingener, Juliane
2008-01-01
Music education affects the mathematical and visuo-spatial skills of school-age children. Visuo-spatial abilities have a significant effect on laparoscopic suturing performance. We hypothesize that prior music experience influences the performance of laparoscopic suturing tasks. Thirty novices observed a laparoscopic suturing task video. Each performed 3 timed suturing task trials. Demographics were recorded. A repeated measures linear mixed model was used to examine the effects of prior music experience on suturing task time. Twelve women and 18 men completed the tasks. When adjusted for video game experience, participants who currently played an instrument performed significantly faster than those who did not (P<0.001). The model showed a significant sex by instrument interaction. Men who had never played an instrument or were currently playing an instrument performed better than women in the same group (P=0.002 and P<0.001). There was no sex difference in the performance of participants who had played an instrument in the past (P=0.29). This study attempted to investigate the effect of music experience on the laparoscopic suturing abilities of surgical novices. The visuo-spatial abilities used in laparoscopic suturing may be enhanced in those involved in playing an instrument.
Delivering Faster Congestion Feedback with the Mark-Front Strategy
NASA Technical Reports Server (NTRS)
Liu, Chunlei; Jain, Raj
2001-01-01
Computer networks use congestion feedback from the routers and destinations to control the transmission load. Delivering timely congestion feedback is essential to the performance of networks. Reaction to the congestion can be more effective if faster feedback is provided. Current TCP/IP networks use timeout, duplicate Acknowledgement Packets (ACKs) and explicit congestion notification (ECN) to deliver the congestion feedback, each provides a faster feedback than the previous method. In this paper, we propose a markfront strategy that delivers an even faster congestion feedback. With analytical and simulation results, we show that mark-front strategy reduces buffer size requirement, improves link efficiency and provides better fairness among users. Keywords: Explicit Congestion Notification, mark-front, congestion control, buffer size requirement, fairness.
Short-term Recovery Following Resistance Exercise Leading or not to Failure.
González-Badillo, J J; Rodríguez-Rosell, D; Sánchez-Medina, L; Ribas, J; López-López, C; Mora-Custodio, R; Yañez-García, J M; Pareja-Blanco, F
2016-04-01
This study analyzed the time course of recovery following 2 resistance exercise protocols differing in level of effort: maximum (to failure) vs. half-maximum number of repetitions per set. 9 males performed 3 sets of 4 vs. 8 repetitions with their 80% 1RM load, 3×4(8) vs. 3×8(8), in the bench press and squat. Several time-points from 24 h pre- to 48 h post-exercise were established to assess the mechanical (countermovement jump height, CMJ; velocity against the 1 m·s(-1) load, V1-load), biochemical (testosterone, cortisol, GH, prolactin, IGF-1, CK) and heart rate variability (HRV) and complexity (HRC) response to exercise. 3×8(8) resulted in greater neuromuscular fatigue (higher reductions in repetition velocity and velocity against V1-load) than 3×4(8). CMJ remained reduced up to 48 h post-exercise following 3×8(8), whereas it was recovered after 6 h for 3×4(8). Significantly greater prolactin and IGF-1 levels were found for 3×8(8) vs. 3×4(8). Significant reductions in HRV and HRC were observed for 3×8(8) vs. 3×4(8) in the immediate recovery. Performing a half-maximum number of repetitions per set resulted in: 1) a stimulus of faster mean repetition velocities; 2) lower impairment of neuromuscular performance and faster recovery; 3) reduced hormonal response and muscle damage; and 4) lower reduction in HRV and HRC following exercise. © Georg Thieme Verlag KG Stuttgart · New York.
Acceleration capability in elite sprinters and ground impulse: Push more, brake less?
Morin, Jean-Benoît; Slawinski, Jean; Dorel, Sylvain; de Villareal, Eduardo Saez; Couturier, Antoine; Samozino, Pierre; Brughelli, Matt; Rabita, Giuseppe
2015-09-18
Overground sprint studies have shown the importance of net horizontal ground reaction force impulse (IMPH) for acceleration performance, but only investigated one or two steps over the acceleration phase, and not in elite sprinters. The main aim of this study was to distinguish between propulsive (IMPH+) and braking (IMPH-) components of the IMPH and seek whether, for an expected higher IMPH, faster elite sprinters produce greater IMPH+, smaller IMPH-, or both. Nine high-level sprinters (100-m best times range: 9.95-10.60s) performed 7 sprints (2×10 m, 2×15 m, 20 m, 30 m and 40 m) during which ground reaction force was measured by a 6.60 m force platform system. By placing the starting-blocks further from the force plates at each trial, and pooling the data, we could assess the mechanics of an entire "virtual" 40-m acceleration. IMPH and IMPH+ were significantly correlated with 40-m mean speed (r=0.868 and 0.802, respectively; P<0.01), whereas vertical impulse and IMPH- were not. Multiple regression analyses confirmed the significantly higher importance of IMPH+ for sprint acceleration performance. Similar results were obtained when considering these mechanical data averaged over the first half of the sprint, but not over the second half. In conclusion, faster sprinters were those who produced the highest amounts of horizontal net impulse per unit body mass, and those who "pushed more" (higher IMPH+), but not necessarily those who also "braked less" (lower IMPH-) in the horizontal direction. Copyright © 2015 Elsevier Ltd. All rights reserved.
Galea, L A; Ossenkopp, K P; Kavaliers, M
1994-01-31
Spatial learning in pre- and postweaning meadow voles, (Microtus pennsylvanicus) was examined in a Morris water-maze task. The learning performance of 10-day-old (preweaning) and 15-, 20- and 25-day-old (postweaning) male and female voles was assessed by measuring the latency to reach a hidden platform by each animal twice a day for 5 days. Voles of all age groups were able to learn the spatial task with Day 10 and Day 15 voles acquiring the task more slowly than did Day 20 and Day 25 voles. There were no significant sex differences in task acquisition in any of the four age groups. In addition, although swimming speed was related to age, with older animals swimming faster than younger ones, differences in swim speed did not account for the faster acquisition by the older animals. These results show that both preweaning and postweaning voles can successfully learn a spatial task. This is in contrast to preweaning laboratory rats which cannot successfully acquire a similar spatial task. These findings indicate that there are species differences in the ontogeny of spatial learning, which are likely related to the ecological and behavioural developmental characteristics of the species. Furthermore, in contrast to the sex difference in water-maze performance obtained in adult, breeding meadow voles who demonstrate a sex difference, there were no significant sex differences in the spatial performance of the juvenile voles. This suggests that sex differences in spatial learning in the meadow vole do not appear until voles reach reproductive adulthood.
MetAlign 3.0: performance enhancement by efficient use of advances in computer hardware.
Lommen, Arjen; Kools, Harrie J
2012-08-01
A new, multi-threaded version of the GC-MS and LC-MS data processing software, metAlign, has been developed which is able to utilize multiple cores on one PC. This new version was tested using three different multi-core PCs with different operating systems. The performance of noise reduction, baseline correction and peak-picking was 8-19 fold faster compared to the previous version on a single core machine from 2008. The alignment was 5-10 fold faster. Factors influencing the performance enhancement are discussed. Our observations show that performance scales with the increase in processor core numbers we currently see in consumer PC hardware development.
Computed Tomography Window Blending: Feasibility in Thoracic Trauma.
Mandell, Jacob C; Wortman, Jeremy R; Rocha, Tatiana C; Folio, Les R; Andriole, Katherine P; Khurana, Bharti
2018-02-07
This study aims to demonstrate the feasibility of processing computed tomography (CT) images with a custom window blending algorithm that combines soft-tissue, bone, and lung window settings into a single image; to compare the time for interpretation of chest CT for thoracic trauma with window blending and conventional window settings; and to assess diagnostic performance of both techniques. Adobe Photoshop was scripted to process axial DICOM images from retrospective contrast-enhanced chest CTs performed for trauma with a window-blending algorithm. Two emergency radiologists independently interpreted the axial images from 103 chest CTs with both blended and conventional windows. Interpretation time and diagnostic performance were compared with Wilcoxon signed-rank test and McNemar test, respectively. Agreement with Nexus CT Chest injury severity was assessed with the weighted kappa statistic. A total of 13,295 images were processed without error. Interpretation was faster with window blending, resulting in a 20.3% time saving (P < .001), with no difference in diagnostic performance, within the power of the study to detect a difference in sensitivity of 5% as determined by post hoc power analysis. The sensitivity of the window-blended cases was 82.7%, compared to 81.6% for conventional windows. The specificity of the window-blended cases was 93.1%, compared to 90.5% for conventional windows. All injuries of major clinical significance (per Nexus CT Chest criteria) were correctly identified in all reading sessions, and all negative cases were correctly classified. All readers demonstrated near-perfect agreement with injury severity classification with both window settings. In this pilot study utilizing retrospective data, window blending allows faster preliminary interpretation of axial chest CT performed for trauma, with no significant difference in diagnostic performance compared to conventional window settings. Future studies would be required to assess the utility of window blending in clinical practice. Copyright © 2018 The Association of University Radiologists. All rights reserved.
Zhang, Wei; Tang, Xiaoxiang; He, Xianyou; Lai, Shuxian
2018-01-01
Substantial evidence suggests that beauty is associated with the survival and reproduction of organisms. Landscape architecture is composed of a series of natural elements that have significant evolutionary implications. The present study used one pilot material ratings and three experiments to examine the mechanisms of aesthetic appraisals of landscape architecture. The results confirmed that landscape architecture elicited a sense of beauty and captured visual attention more easily than other types of architecture during explicit aesthetic rating task (Experiment 1) and implicit aesthetic perception task (dot-probe paradigm, Experiment 2). Furthermore, the spatial cueing paradigm revealed that response latencies were significantly faster for landscape architecture than non-landscape architecture on valid trials, but there was no significant difference in this contrast on invalid trials at 150-ms stimulus onset asynchrony (SOA, Experiment 3a). At 500-ms SOA (Experiment 3b), participants responded significantly faster for landscape architecture on valid trials, but reacted significantly slower for landscape architecture on invalid trials. The findings indicated that the beauty of landscape architecture can be perceived implicitly, and only faster orienting of attention, but not delayed disengagement of attention was generated at early stages of the processing of landscape architecture. However, the attentional bias at later stages of attentional processes may be resulted from both faster orienting of attention and delayed disengagement of attention from landscape architecture photographs. PMID:29467696
Zhang, Wei; Tang, Xiaoxiang; He, Xianyou; Lai, Shuxian
2018-01-01
Substantial evidence suggests that beauty is associated with the survival and reproduction of organisms. Landscape architecture is composed of a series of natural elements that have significant evolutionary implications. The present study used one pilot material ratings and three experiments to examine the mechanisms of aesthetic appraisals of landscape architecture. The results confirmed that landscape architecture elicited a sense of beauty and captured visual attention more easily than other types of architecture during explicit aesthetic rating task (Experiment 1) and implicit aesthetic perception task (dot-probe paradigm, Experiment 2). Furthermore, the spatial cueing paradigm revealed that response latencies were significantly faster for landscape architecture than non-landscape architecture on valid trials, but there was no significant difference in this contrast on invalid trials at 150-ms stimulus onset asynchrony (SOA, Experiment 3a). At 500-ms SOA (Experiment 3b), participants responded significantly faster for landscape architecture on valid trials, but reacted significantly slower for landscape architecture on invalid trials. The findings indicated that the beauty of landscape architecture can be perceived implicitly, and only faster orienting of attention, but not delayed disengagement of attention was generated at early stages of the processing of landscape architecture. However, the attentional bias at later stages of attentional processes may be resulted from both faster orienting of attention and delayed disengagement of attention from landscape architecture photographs.
Salihu, Lejla; Rüst, Christoph Alexander; Rosemann, Thomas; Knechtle, Beat
2016-04-30
Recent studies reported that the sex difference in performance in ultra-endurance sports such as swimming and cycling changed over the years. However, the aspect of drafting in draft-legal ultra-endurance races has not yet been investigated. This study investigates the sex difference in ultra-swimming and ultra-cycling draft-legal races where drafting - swimming or cycling behind other participants to save energy and have more power at the end of the race to overtake them, is allowed. The change in performance of the annual best and the annual three best in an ultra-endurance swimming race (16-km 'Faros Swim Marathon') over 38 years and in a 24-h ultra-cycling race ('World Cycling Race') over 13 years were compared and analysed with respect to sex difference. Furthermore, performances of the fastest female and male finishers ever were compared. In the swimming event, the sex difference of the annual best male and female decreased non-significantly (P = 0.262) from 5.3% (1976) to 1.0% (2013). The sex gap of speed in the annual three fastest swimmers decreased significantly (P = 0.043) from 5.9 ± 1.6% (1979) to 4.7 ± 3.1% (2013). In the cycling event, the difference in cycling speed between the annual best male and female decreased significantly (P = 0.026) from 33.31% (1999) to 10.89% (2011). The sex gap of speed in the annual three fastest decreased significantly (P = 0.001) from 32.9 ± 0.6% (1999) to 16.4 ± 5.9% (2011). The fastest male swimmer ever (swimming speed 5.3 km/h, race time: 03:01:55 h:min:s) was 1.5% faster than the fastest female swimmer (swimming speed 5.2 km/h, race time: 03:04:09 h:min:s). The three fastest male swimmers ever (mean 5.27 ± 0.13 km/h) were 4.4% faster than the three fastest female swimmers (mean 5.05 ± 0.20 km/h) (P < 0.05). In the cycling event, the best male ever (cycling speed 45.8 km/h) was 26.4% faster than the best female (cycling speed 36.1 km/h). The three fastest male cyclists ever (45.9 km/h) (mean 45.85 ± 0.05 km/h) were 32.1% faster (P < 0.05) than the three fastest female cyclists ever (34.7 km/h) (mean 34.70 ± 1.87 km/h). In summary, in draft-legal ultra-distance events such as swimming and cycling, the sex difference in the annual top and annual top three swimmers and cyclists decreased (i.e. non-linearly in swimmers and linearly in cyclists) over the years. The sex difference of the fastest athletes ever was smaller in swimming (1.5%) than in cycling (26.4%). This finding is different from reports about races where drafting was not possible or even prohibited and where the sex difference remained stable over years.
Lighting in digital game worlds: effects on affect and play performance.
Knez, Igor; Niedenthal, Simon
2008-04-01
As a means of extending the significance of findings in experimental psychology and nonvisual psychological lighting research to digital game research, the present study was designed to investigate the impact of warm (reddish) and cool (bluish) simulated illumination in digital game worlds on game users' affect and play performance. In line with some previous findings, we predicted that lighting in a digital game world might, as in the real world, differently influence the nonvisual psychological mechanisms of affect, which in turn might enhance or impair the players' performance. It was shown that the players performed best and fastest in a game world lit with a warm (reddish) as compared to a cool (bluish) lighting. The former color of lighting also induced the highest level of pleasantness in game users. A regression analysis indicated tentatively that it was the level of pleasantness induced by the warm lighting that enhanced the players' better performance in that digital game world. It was also shown that high- as opposed to medium- or low-skilled players engage almost 2.5 times more per week in game playing. Given their skill, they performed significantly faster and felt significantly calmer and more relaxed in doing so.
Effects of youth football on selected clinical measures of neurologic function: a pilot study.
Munce, Thayne A; Dorman, Jason C; Odney, Tryg O; Thompson, Paul A; Valentine, Verle D; Bergeron, Michael F
2014-12-01
We assessed 10 youth football players (13.4 ± 0.7 y) immediately before and after their season to explore the effects of football participation on selected clinical measures of neurologic function. Postseason postural stability in a closed-eye condition was improved compared to preseason (P = .017). Neurocognitive testing with the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) battery revealed that reaction time was significantly faster at postseason (P = .015). There were no significant preseason versus postseason differences in verbal memory (P = .507), visual memory (P = .750), or visual motor speed (P = .087). Oculomotor performance assessed by the King-Devick test was moderately to significantly improved (P = .047-.115). A 12-week season of youth football did not impair the postural stability, neurocognitive function, or oculomotor performance measures of the players evaluated. Though encouraging, continued and more comprehensive investigations of this at-risk population are warranted. © The Author(s) 2013.
Self- or familiar-face recognition advantage? New insight using ambient images.
Bortolon, Catherine; Lorieux, Siméon; Raffard, Stéphane
2018-06-01
Self-face recognition has been widely explored in the past few years. Nevertheless, the current literature relies on the use of standardized photographs which do not represent daily-life face recognition. Therefore, we aim for the first time to evaluate self-face processing in healthy individuals using natural/ambient images which contain variations in the environment and in the face itself. In total, 40 undergraduate and graduate students performed a forced delayed-matching task, including images of one's own face, friend, famous and unknown individuals. For both reaction time and accuracy, results showed that participants were faster and more accurate when matching different images of their own face compared to both famous and unfamiliar faces. Nevertheless, no significant differences were found between self-face and friend-face and between friend-face and famous-face. They were also faster and more accurate when matching friend and famous faces compared to unfamiliar faces. Our results suggest that faster and more accurate responses to self-face might be better explained by a familiarity effect - that is, (1) the result of frequent exposition to one's own image through mirror and photos, (2) a more robust mental representation of one's own face and (3) strong face recognition units as for other familiar faces.
Graham, Eileen K; Lachman, Margie E
2012-09-01
Although personality is relatively stable over time, there are individual differences in the patterns and magnitude of change. There is some evidence that personality change in adulthood is related to physical health and longevity. The present study expanded this work to consider whether personality stability or change would be associated with better cognitive functioning, especially in later adulthood. A total of 4,974 individuals participated in two waves of The Midlife in the United States Study (MIDUS) in 1994-1995 and 2004-2005. Participants completed the MIDUS personality inventory at both times and the Brief Test of Adult Cognition by Telephone cognitive battery at Time 2. Multiple regression and analysis of covariance analyses showed that, consistent with predictions, individuals remaining stable in openness to experience and neuroticism had faster reaction times and better inductive reasoning than those who changed. Among older adults, those who remained stable or decreased in neuroticism had significantly faster reaction times than those who increased. As predicted, personality stability on some traits was associated with more adaptive cognitive performance on reasoning and reaction time. Personality is discussed as a possible resource for protecting against or minimizing age-related declines in cognition.
Faster Self-paced Rate of Drinking for Alcohol Mixed with Energy Drinks versus Alcohol Alone
Marczinski, Cecile A.; Fillmore, Mark T.; Maloney, Sarah F.; Stamates, Amy L.
2016-01-01
The consumption of alcohol mixed with energy drinks (AmED) has been associated with higher rates of binge drinking and impaired driving when compared to alcohol alone. However, it remains unclear why the risks of use of AmED are heightened compared to alcohol alone even when the doses of alcohol consumed are similar. Therefore, the purpose of this laboratory study was to investigate if the rate of self-paced beverage consumption was faster for a dose of AmED versus alcohol alone using a double-blind, within-subjects, placebo-controlled study design. Participants (n = 16) of equal gender who were social drinkers attended 4 separate test sessions that involved consumption of alcohol (1.97 ml/kg vodka) and energy drinks, alone and in combination. On each test day, the dose assigned was divided into 10 cups. Participants were informed that they would have a two hour period to consume the 10 drinks. After the self-paced drinking period, participants completed a cued go/no-go reaction time task and subjective ratings of stimulation and sedation. The results indicated that participants consumed the AmED dose significantly faster (by approximately 16 minutes) than the alcohol dose. For the performance task, participants’ mean reaction times were slower in the alcohol conditions and faster in the energy drink conditions. In conclusion, alcohol consumers should be made aware that rapid drinking might occur for AmED beverages thus heightening alcohol-related safety risks. The fast rate of drinking may be related to the generalized speeding of responses following energy drink consumption. PMID:27819431
Faster Smith-Waterman database searches with inter-sequence SIMD parallelisation
2011-01-01
Background The Smith-Waterman algorithm for local sequence alignment is more sensitive than heuristic methods for database searching, but also more time-consuming. The fastest approach to parallelisation with SIMD technology has previously been described by Farrar in 2007. The aim of this study was to explore whether further speed could be gained by other approaches to parallelisation. Results A faster approach and implementation is described and benchmarked. In the new tool SWIPE, residues from sixteen different database sequences are compared in parallel to one query residue. Using a 375 residue query sequence a speed of 106 billion cell updates per second (GCUPS) was achieved on a dual Intel Xeon X5650 six-core processor system, which is over six times more rapid than software based on Farrar's 'striped' approach. SWIPE was about 2.5 times faster when the programs used only a single thread. For shorter queries, the increase in speed was larger. SWIPE was about twice as fast as BLAST when using the BLOSUM50 score matrix, while BLAST was about twice as fast as SWIPE for the BLOSUM62 matrix. The software is designed for 64 bit Linux on processors with SSSE3. Source code is available from http://dna.uio.no/swipe/ under the GNU Affero General Public License. Conclusions Efficient parallelisation using SIMD on standard hardware makes it possible to run Smith-Waterman database searches more than six times faster than before. The approach described here could significantly widen the potential application of Smith-Waterman searches. Other applications that require optimal local alignment scores could also benefit from improved performance. PMID:21631914
Faster Smith-Waterman database searches with inter-sequence SIMD parallelisation.
Rognes, Torbjørn
2011-06-01
The Smith-Waterman algorithm for local sequence alignment is more sensitive than heuristic methods for database searching, but also more time-consuming. The fastest approach to parallelisation with SIMD technology has previously been described by Farrar in 2007. The aim of this study was to explore whether further speed could be gained by other approaches to parallelisation. A faster approach and implementation is described and benchmarked. In the new tool SWIPE, residues from sixteen different database sequences are compared in parallel to one query residue. Using a 375 residue query sequence a speed of 106 billion cell updates per second (GCUPS) was achieved on a dual Intel Xeon X5650 six-core processor system, which is over six times more rapid than software based on Farrar's 'striped' approach. SWIPE was about 2.5 times faster when the programs used only a single thread. For shorter queries, the increase in speed was larger. SWIPE was about twice as fast as BLAST when using the BLOSUM50 score matrix, while BLAST was about twice as fast as SWIPE for the BLOSUM62 matrix. The software is designed for 64 bit Linux on processors with SSSE3. Source code is available from http://dna.uio.no/swipe/ under the GNU Affero General Public License. Efficient parallelisation using SIMD on standard hardware makes it possible to run Smith-Waterman database searches more than six times faster than before. The approach described here could significantly widen the potential application of Smith-Waterman searches. Other applications that require optimal local alignment scores could also benefit from improved performance.
Improving Explicit Congestion Notification with the Mark-Front Strategy
NASA Technical Reports Server (NTRS)
Liu, Chunlei; Jain, Raj
2001-01-01
Delivering congestion signals is essential to the performance of networks. Current TCP/IP networks use packet losses to signal congestion. Packet losses not only reduces TCP performance, but also adds large delay. Explicit Congestion Notification (ECN) delivers a faster indication of congestion and has better performance. However, current ECN implementations mark the packet from the tail of the queue. In this paper, we propose the mark-front strategy to send an even faster congestion signal. We show that mark-front strategy reduces buffer size requirement, improves link efficiency and provides better fairness among users. Simulation results that verify our analysis are also presented.
Cooper, Caitlin A.; Garas Klobas, Lydia C.; Maga, Elizabeth A.; Murray, James D.
2013-01-01
Childhood diarrhea is a significant problem in many developing countries and E. coli is a main causative agent of diarrhea in young children. Lysozyme is an antimicrobial protein highly expressed in human milk, but not ruminant milk, and is thought to help protect breastfeeding children against diarrheal diseases. We hypothesized that consumption of milk from transgenic goats which produce human lysozyme (hLZ-milk) in their milk would accelerate recovery from bacterial-induced diarrhea. Young pigs were used as a model for children and infected with enterotoxigenic E. coli. Once clinical signs of diarrhea developed, pigs were fed hLZ-milk or non-transgenic control goat milk three times a day for two days. Clinical observations and complete blood counts (CBC) were performed. Animals were euthanized and samples collected to assess differences in histology, cytokine expression and bacterial translocation into the mesenteric lymph node. Pigs consuming hLZ-milk recovered from clinical signs of infection faster than pigs consuming control milk, with significantly improved fecal consistency (p = 0.0190) and activity level (p = 0.0350). The CBC analysis showed circulating monocytes (p = 0.0413), neutrophils (p = 0.0219), and lymphocytes (p = 0.0222) returned faster to pre-infection proportions in hLZ-milk fed pigs, while control-fed pigs had significantly higher hematocrit (p = 0.027), indicating continuing dehydration. In the ileum, pigs fed hLZ-milk had significantly lower expression of pro-inflammatory cytokine IL-8 (p = 0.0271), longer intestinal villi (p<0.0001), deeper crypts (p = 0.0053), and a thinner lamina propria (p = 0.0004). These data demonstrate that consumption of hLZ-milk helped pigs recover from infection faster, making hLZ-milk an effective treatment of E. coli-induced diarrhea. PMID:23516474
Burnfield, Judith M; Eberly, Valerie J; Gronely, Joanne K; Perry, Jacquelin; Yule, William Jared; Mulroy, Sara J
2012-03-01
Microprocessor controlled prosthetic knees (MPK) offer opportunities for improved walking stability and function, but some devices' swing phase features may exceed needs of users with invariable cadence. One MPK offers computerized control of only stance (C-Leg Compact). To assess Medicare Functional Classification Level K2 walkers' ramp negotiation performance, function and balance while using a non-MPK (NMPK) compared to the C-Leg Compact. Crossover. Gait while ascending and descending a ramp (stride characteristics, kinematics, electromyography) and function were assessed in participant's existing NMPK and again in the C-Leg Compact following accommodation. Ramp ascent and descent were markedly faster in the C-Leg Compact compared to the NMPK (p ≤ 0.006), owing to increases in stride length (p ≤ 0.020) and cadence (p ≤ 0.020). Residual limb peak knee flexion and ankle dorsiflexion were significantly greater (12.9° and 4.9° more, respectively) during single limb support while using the C-Leg Compact to descend ramps. Electromyography (mean, peak) did not differ significantly between prosthesis. Function improved in the C-Leg Compact as evidenced by a significantly faster Timed Up and Go and higher functional questionnaire scores. Transfemoral K2 walkers exhibited significantly improved function and balance while using the stance-phase only MPK compared to their traditional NMPK.
Design of the computerized 3D endoscopic imaging system for delicate endoscopic surgery.
Song, Chul-Gyu; Kang, Jin U
2011-02-01
This paper describes a 3D endoscopic video system designed to improve visualization and enhance the ability of the surgeon to perform delicate endoscopic surgery. In a comparison of the polarized and conventional electric shutter-type stereo imaging systems, the former was found to be superior in terms of both accuracy and speed for suturing and for the loop pass test. Among the groups performing loop passing and suturing, there was no significant difference in the task performance between the 2D and 3D modes, however, suturing was performed 15% (p < 0.05) faster in 3D mode by both groups. The results of our experiments show that the proposed 3D endoscopic system has a sufficiently wide viewing angle and zone for multi-viewing.
Altmann, Lori J. P.; Stegemöller, Elizabeth; Hazamy, Audrey A.; Wilson, Jonathan P.; Okun, Michael S.; McFarland, Nikolaus R.; Shukla, Aparna Wagle; Hass, Chris J.
2015-01-01
Background When performing two tasks at once, a dual task, performance on one or both tasks typically suffers. People with Parkinson’s disease (PD) usually experience larger dual task decrements on motor tasks than healthy older adults (HOA). Our objective was to investigate the decrements in cycling caused by performing cognitive tasks with a range of difficulty in people with PD and HOAs. Methods Twenty-eight participants with Parkinson’s disease and 20 healthy older adults completed a baseline cycling task with no secondary tasks and then completed dual task cycling while performing 12 tasks from six cognitive domains representing a wide range of difficulty. Results Cycling was faster during dual task conditions than at baseline, and was significantly faster for six tasks (all p<.02) across both groups. Cycling speed improved the most during the easiest cognitive tasks, and cognitive performance was largely unaffected. Cycling improvement was predicted by task difficulty (p<.001). People with Parkinson’s disease cycled slower (p<.03) and showed reduced dual task benefits (p<.01) than healthy older adults. Conclusions Unexpectedly, participants’ motor performance improved during cognitive dual tasks, which cannot be explained in current models of dual task performance. To account for these findings, we propose a model integrating dual task and acute exercise approaches which posits that cognitive arousal during dual tasks increases resources to facilitate motor and cognitive performance, which is subsequently modulated by motor and cognitive task difficulty. This model can explain both the improvement observed on dual tasks in the current study and more typical dual task findings in other studies. PMID:25970607
Sugammadex: A Review of Neuromuscular Blockade Reversal.
Keating, Gillian M
2016-07-01
Sugammadex (Bridion(®)) is a modified γ-cyclodextrin that reverses the effect of the steroidal nondepolarizing neuromuscular blocking agents rocuronium and vecuronium. Intravenous sugammadex resulted in rapid, predictable recovery from moderate and deep neuromuscular blockade in patients undergoing surgery who received rocuronium or vecuronium. Recovery from moderate neuromuscular blockade was significantly faster with sugammadex 2 mg/kg than with neostigmine, and recovery from deep neuromuscular blockade was significantly faster with sugammadex 4 mg/kg than with neostigmine or spontaneous recovery. In addition, recovery from neuromuscular blockade was significantly faster when sugammadex 16 mg/kg was administered 3 min after rocuronium than when patients spontaneously recovered from succinylcholine. Sugammadex also demonstrated efficacy in various special patient populations, including patients with pulmonary disease, cardiac disease, hepatic dysfunction or myasthenia gravis and morbidly obese patients. Intravenous sugammadex was generally well tolerated. In conclusion, sugammadex is an important option for the rapid reversal of rocuronium- or vecuronium-induced neuromuscular blockade.
Lavender fragrance cleansing gel effects on relaxation.
Field, Tiffany; Diego, Miguel; Hernandez-Reif, Maria; Cisneros, Wendy; Feijo, Larissa; Vera, Yanexy; Gil, Karla; Grina, Diana; Claire He, Qing
2005-02-01
Alertness, mood, and math computations were assessed in 11 healthy adults who sniffed a cosmetic cleansing gel with lavender floral blend aroma, developed to be relaxing using Mood Mapping. EEG patterns and heart rate were also recorded before, during, and after the aroma session. The lavender fragrance blend had a significant transient effect of improving mood, making people feel more relaxed, and performing the math computation faster. The self-report and physiological data are consistent with relaxation profiles during other sensory stimuli such as massage and music, as reported in the literature. The data suggest that a specific cosmetic fragrance can have a significant role in enhancing relaxation.
Preserved Discrimination Performance and Neural Processing during Crossmodal Attention in Aging
Mishra, Jyoti; Gazzaley, Adam
2013-01-01
In a recent study in younger adults (19-29 year olds) we showed evidence that distributed audiovisual attention resulted in improved discrimination performance for audiovisual stimuli compared to focused visual attention. Here, we extend our findings to healthy older adults (60-90 year olds), showing that performance benefits of distributed audiovisual attention in this population match those of younger adults. Specifically, improved performance was revealed in faster response times for semantically congruent audiovisual stimuli during distributed relative to focused visual attention, without any differences in accuracy. For semantically incongruent stimuli, discrimination accuracy was significantly improved during distributed relative to focused attention. Furthermore, event-related neural processing showed intact crossmodal integration in higher performing older adults similar to younger adults. Thus, there was insufficient evidence to support an age-related deficit in crossmodal attention. PMID:24278464
Large-scale seismic waveform quality metric calculation using Hadoop
Magana-Zook, Steven; Gaylord, Jessie M.; Knapp, Douglas R.; ...
2016-05-27
Here in this work we investigated the suitability of Hadoop MapReduce and Apache Spark for large-scale computation of seismic waveform quality metrics by comparing their performance with that of a traditional distributed implementation. The Incorporated Research Institutions for Seismology (IRIS) Data Management Center (DMC) provided 43 terabytes of broadband waveform data of which 5.1 TB of data were processed with the traditional architecture, and the full 43 TB were processed using MapReduce and Spark. Maximum performance of ~0.56 terabytes per hour was achieved using all 5 nodes of the traditional implementation. We noted that I/O dominated processing, and that I/Omore » performance was deteriorating with the addition of the 5th node. Data collected from this experiment provided the baseline against which the Hadoop results were compared. Next, we processed the full 43 TB dataset using both MapReduce and Apache Spark on our 18-node Hadoop cluster. We conducted these experiments multiple times with various subsets of the data so that we could build models to predict performance as a function of dataset size. We found that both MapReduce and Spark significantly outperformed the traditional reference implementation. At a dataset size of 5.1 terabytes, both Spark and MapReduce were about 15 times faster than the reference implementation. Furthermore, our performance models predict that for a dataset of 350 terabytes, Spark running on a 100-node cluster would be about 265 times faster than the reference implementation. We do not expect that the reference implementation deployed on a 100-node cluster would perform significantly better than on the 5-node cluster because the I/O performance cannot be made to scale. Finally, we note that although Big Data technologies clearly provide a way to process seismic waveform datasets in a high-performance and scalable manner, the technology is still rapidly changing, requires a high degree of investment in personnel, and will likely require significant changes in other parts of our infrastructure. Nevertheless, we anticipate that as the technology matures and third-party tool vendors make it easier to manage and operate clusters, Hadoop (or a successor) will play a large role in our seismic data processing.« less
Large-scale seismic waveform quality metric calculation using Hadoop
DOE Office of Scientific and Technical Information (OSTI.GOV)
Magana-Zook, Steven; Gaylord, Jessie M.; Knapp, Douglas R.
Here in this work we investigated the suitability of Hadoop MapReduce and Apache Spark for large-scale computation of seismic waveform quality metrics by comparing their performance with that of a traditional distributed implementation. The Incorporated Research Institutions for Seismology (IRIS) Data Management Center (DMC) provided 43 terabytes of broadband waveform data of which 5.1 TB of data were processed with the traditional architecture, and the full 43 TB were processed using MapReduce and Spark. Maximum performance of ~0.56 terabytes per hour was achieved using all 5 nodes of the traditional implementation. We noted that I/O dominated processing, and that I/Omore » performance was deteriorating with the addition of the 5th node. Data collected from this experiment provided the baseline against which the Hadoop results were compared. Next, we processed the full 43 TB dataset using both MapReduce and Apache Spark on our 18-node Hadoop cluster. We conducted these experiments multiple times with various subsets of the data so that we could build models to predict performance as a function of dataset size. We found that both MapReduce and Spark significantly outperformed the traditional reference implementation. At a dataset size of 5.1 terabytes, both Spark and MapReduce were about 15 times faster than the reference implementation. Furthermore, our performance models predict that for a dataset of 350 terabytes, Spark running on a 100-node cluster would be about 265 times faster than the reference implementation. We do not expect that the reference implementation deployed on a 100-node cluster would perform significantly better than on the 5-node cluster because the I/O performance cannot be made to scale. Finally, we note that although Big Data technologies clearly provide a way to process seismic waveform datasets in a high-performance and scalable manner, the technology is still rapidly changing, requires a high degree of investment in personnel, and will likely require significant changes in other parts of our infrastructure. Nevertheless, we anticipate that as the technology matures and third-party tool vendors make it easier to manage and operate clusters, Hadoop (or a successor) will play a large role in our seismic data processing.« less
Lesions of the lateral habenula facilitate active avoidance learning and threat extinction.
Song, Mihee; Jo, Yong Sang; Lee, Yeon-Kyung; Choi, June-Seek
2017-02-01
The lateral habenula (LHb) is an epithalamic brain structure that provides strong projections to midbrain monoaminergic systems that are involved in motivation, emotion, and reinforcement learning. LHb neurons are known to convey information about aversive outcomes and negative prediction errors, suggesting a role in learning from aversive events. To test this idea, we examined the effects of electrolytic lesions of the LHb on signaled two-way active avoidance learning in which rats were trained to avoid an unconditioned stimulus (US) by taking a proactive shuttling response to an auditory conditioned stimulus (CS). The lesioned animals learned the avoidance response significantly faster than the control groups. In a separate experiment, we also investigated whether the LHb contributes to Pavlovian threat (fear) conditioning and extinction. Following paired presentations of the CS and the US, LHb-lesioned animals showed normal acquisition of conditioned response (CR) measured with freezing. However, extinction of the CR in the subsequent CS-only session was significantly faster. The enhanced performance in avoidance learning and in threat extinction jointly suggests that the LHb normally plays an inhibitory role in learning driven by absence of aversive outcomes. Copyright © 2016 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Huang, Renke; Jin, Shuangshuang; Chen, Yousu
This paper presents a faster-than-real-time dynamic simulation software package that is designed for large-size power system dynamic simulation. It was developed on the GridPACKTM high-performance computing (HPC) framework. The key features of the developed software package include (1) faster-than-real-time dynamic simulation for a WECC system (17,000 buses) with different types of detailed generator, controller, and relay dynamic models, (2) a decoupled parallel dynamic simulation algorithm with optimized computation architecture to better leverage HPC resources and technologies, (3) options for HPC-based linear and iterative solvers, (4) hidden HPC details, such as data communication and distribution, to enable development centered on mathematicalmore » models and algorithms rather than on computational details for power system researchers, and (5) easy integration of new dynamic models and related algorithms into the software package.« less
Dyslexie font does not benefit reading in children with or without dyslexia.
Kuster, Sanne M; van Weerdenburg, Marjolijn; Gompel, Marjolein; Bosman, Anna M T
2018-04-01
In two experiments, the claim was tested that the font "Dyslexie", specifically designed for people with dyslexia, eases reading performance of children with (and without) dyslexia. Three questions were investigated. (1) Does the Dyslexie font lead to faster and/or more accurate reading? (2) Do children have a preference for the Dyslexie font? And, (3) is font preference related to reading performance? In Experiment 1, children with dyslexia (n = 170) did not read text written in Dyslexie font faster or more accurately than in Arial font. The majority preferred reading in Arial and preference was not related to reading performance. In Experiment 2, children with (n = 102) and without dyslexia (n = 45) read word lists in three different font types (Dyslexie, Arial, Times New Roman). Words written in Dyslexie font were not read faster or more accurately. Moreover, participants showed a preference for the fonts Arial and Times New Roman rather than Dyslexie, and again, preference was not related to reading performance. These experiments clearly justify the conclusion that the Dyslexie font neither benefits nor impedes the reading process of children with and without dyslexia.
How Has Internet Use Changed between 2012 and 2015? PISA in Focus No. 83
ERIC Educational Resources Information Center
Echazarra, Alfonso
2018-01-01
In the growing world of digital technology everything is about speed: computer processors have doubled their performance every two years for decades; the future 5G mobile phone generation is predicted to be about 100 times faster than the current 4G and 20 000 times faster than the "ancient" 3G; and, according to the International…
2012-01-01
Background The purpose of this study was to investigate participation and performance changes in the multistage ultramarathon ‘Marathon des Sables’ from 2003 to 2012. Methods Participation and performance trends in the four- or six-stage running event covering approximately 250 km were analyzed with special emphasis on the nationality and age of the athletes. The relations between gender, age, and nationality of finishers and performance were investigated using regression analyses and analysis of variance. Results Between 2003 and 2012, a number of 7,275 athletes with 938 women (12.9%) and 6,337 men (87.1%) finished the Marathon des Sables. The finisher rate in both women (r2 = 0.62) and men (r2 = 0.60) increased across years (p < 0.01). Men were significantly (p < 0.01) faster than women for overall finishers (5.9 ± 1.6 km·h−1 versus 5.1 ± 1.3 km·h−1) and for the top three finishers (12.2 ± 0.4 km·h−1 versus 8.3 ± 0.6 km·h−1). The gender difference in running speed of the top three athletes decreased (r2 = 0.72; p < 0.01) from 39.5% in 2003 to 24.1% in 2012 with a mean gender difference of 31.7 ± 2.0%. In men, Moroccans won nine of ten competitions, and one edition was won by a Jordanian athlete. In women, eight races were won by Europeans (France five, Luxembourg two, and Spain one, respectively), and two events were won by Moroccan runners. Conclusions The finisher rate in the Marathon des Sables increased this last decade. Men were significantly faster than women with a higher gender difference in performance compared to previous reports. Social or cultural inhibitions may determine the outcome in this event. Future studies need to investigate participation trends regarding nationalities and socioeconomic background, as well as the motivation to compete in ultramarathons. PMID:23849138
Vazini Taher, Amir; Parnow, Abdolhossein
2017-05-01
Different methods of warm-up may have implications in improving various aspects of soccer performance. The present study aimed to investigate acute effects of soccer specific warm-up protocols on functional performance tests. This study using randomized within-subject design, investigated the performance of 22 collegiate elite soccer player following soccer specific warm-ups using dynamic stretching, static stretching, and FIFA 11+ program. Post warm-up examinations consisted: 1) Illinois Agility Test; 2) vertical jump; 3) 30 meter sprint; 4) consecutive turns; 5) flexibility of knee. Vertical jump performance was significantly lower following static stretching, as compared to dynamic stretching (P=0.005). Sprint performance declined significantly following static stretching as compared to FIFA 11+ (P=0.023). Agility time was significantly faster following dynamic stretching as compared to FIFA 11+ (P=0.001) and static stretching (P=0.001). Knee flexibility scores were significantly improved following the static stretching as compared to dynamic stretching (P=016). No significant difference was observed for consecutive turns between three warm-up protocol. The present finding showed that a soccer specific warm-up protocol relied on dynamic stretching is preferable in enhancing performance as compared to protocols relying on static stretches and FIFA 11+ program. Investigators suggest that while different soccer specific warm-up protocols have varied types of effects on performance, acute effects of dynamic stretching on performance in elite soccer players are assured, however application of static stretching in reducing muscle stiffness is demonstrated.
Video game players show higher performance but no difference in speed of attention shifts.
Mack, David J; Wiesmann, Helene; Ilg, Uwe J
2016-09-01
Video games have become both a widespread leisure activity and a substantial field of research. In a variety of tasks, video game players (VGPs) perform better than non-video game players (NVGPs). This difference is most likely explained by an alteration of the basic mechanisms underlying visuospatial attention. More specifically, the present study hypothesizes that VGPs are able to shift attention faster than NVGPs. Such alterations in attention cannot be disentangled from changes in stimulus-response mappings in reaction time based measurements. Therefore, we used a spatial cueing task with varying cue lead times (CLTs) to investigate the speed of covert attention shifts of 98 male participants divided into 36 NVGPs and 62 VGPs based on their weekly gaming time. VGPs exhibited higher peak and mean performance than NVGPs. However, we did not find any differences in the speed of covert attention shifts as measured by the CLT needed to achieve peak performance. Thus, our results clearly rule out faster stimulus-response mappings as an explanation for the higher performance of VGPs in line with previous studies. More importantly, our data do not support the notion of faster attention shifts in VGPs as another possible explanation. Copyright © 2016 Elsevier B.V. All rights reserved.
Faiz, Seyed Hamid Reza; Imani, Farnad; Rahimzadeh, Poupak; Alebouyeh, Mahmoud Reza; Entezary, Saeed Reza; Shafeinia, Amineh
2017-08-01
Peripheral nerve block is an accepted method in lower limb surgeries regarding its convenience and good tolerance by the patients. Quick performance and fast sensory and motor block are highly demanded in this method. The aim of the present study was to compare 2 different methods of sciatic and tibial-peroneal nerve block in lower limb surgeries in terms of block onset. In this clinical trial, 52 candidates for elective lower limb surgery were randomly divided into 2 groups: sciatic nerve block before bifurcation (SG; n = 27) and separate tibial-peroneal nerve block (TPG; n = 25) under ultrasound plus nerve stimulator guidance. The mean duration of block performance, as well as complete sensory and motor block, was recorded and compared between the groups. The mean duration of complete sensory block in the SG and TPG groups was 35.4 ± 4.1 and 24.9 ± 4.2 minutes, respectively, which was significantly lower in the TPG group (P = 0.001). The mean duration of complete motor block in the SG and TPG groups was 63.3 ± 4.4 and 48.4 ± 4.6 minutes, respectively, which was significantly lower in the TPG group (P = 0.001). No nerve injuries, paresthesia, or other possible side effects were reported in patients. According to the present study, it seems that TPG shows a faster sensory and motor block than SG.
Age and education influence the performance of elderly women on the dual-task Timed Up and Go test.
Gomes, Gisele de Cássia; Teixeira-Salmela, Luci Fuscaldi; Fonseca, Bruna Espeschit; Freitas, Flávia Alexandra Silveira de; Fonseca, Maria Luísa Morais; Pacheco, Bruna Débora; Gonçalves, Marisa Rocha; Caramelli, Paulo
2015-03-01
Gait variability is related to functional decline in the elderly. The dual-task Timed Up and Go Test (TUG-DT) reflects the performance in daily activities. Objective To evaluate the differences in time to perform the TUG with and without DT in elderly women with different ages and levels of education and physical activity. Method Ninety-two elderly women perfomed the TUG at usual and fast speeds, with and without motor and cognitive DT. Results Increases in the time to perform the TUG-DT were observed at older ages and lower educational levels, but not at different levels of physical activity. More educated women performed the test faster with and without DT at both speeds. When age was considered, significant differences were found only for the TUG-DT at both speeds. Conclusion Younger women with higher education levels demonstrated better performances on the TUG-DT.
The Role of Personality in a Regular Cognitive Monitoring Program.
Sadeq, Nasreen A; Valdes, Elise G; Harrison Bush, Aryn L; Andel, Ross
2018-02-20
This study examines the role of personality in cognitive performance, adherence, and satisfaction with regular cognitive self-monitoring. One hundred fifty-seven cognitively healthy older adults, age 55+, completed the 44-item Big-Five Inventory and were subsequently engaged in online monthly cognitive monitoring using the Cogstate Brief Battery for up to 35 months (M=14 mo, SD=7 mo). The test measures speed and accuracy in reaction time, visual learning, and working memory tasks. Neuroticism, although not related to cognitive performance overall (P>0.05), was related to a greater increase in accuracy (estimate=0.07, P=0.04) and speed (estimate=-0.09, P=0.03) on One Card Learning. Greater conscientiousness was related to faster overall speed on Detection (estimate=-1.62, P=0.02) and a significant rate of improvement in speed on One Card Learning (estimate=-0.10, P<0.03). No differences in satisfaction or adherence to monthly monitoring as a function of neuroticism or conscientiousness were observed. Participants volunteering for regular cognitive monitoring may be quite uniform in terms of personality traits, with personality traits playing a relatively minor role in adherence and satisfaction. The more neurotic may exhibit better accuracy and improve in speed with time, whereas the more conscientious may perform faster overall and improve in speed on some tasks, but the effects appear small.
Effects of metabolic syndrome on language functions in aging.
Cahana-Amitay, Dalia; Spiro, Avron; Cohen, Jason A; Oveis, Abigail C; Ojo, Emmanuel A; Sayers, Jesse T; Obler, Loraine K; Albert, Martin L
2015-02-01
This study explored effects of the metabolic syndrome (MetS) on language in aging. MetS is a constellation of five vascular and metabolic risk factors associated with the development of chronic diseases and increased risk of mortality, as well as brain and cognitive impairments. We tested 281 English-speaking older adults aged 55-84, free of stroke and dementia. Presence of MetS was based on the harmonized criteria (Alberti et al., 2009). Language performance was assessed by measures of accuracy and reaction time on two tasks of lexical retrieval and two tasks of sentence processing. Regression analyses, adjusted for age, education, gender, diabetes, hypertension, and heart disease, demonstrated that participants with MetS had significantly lower accuracy on measures of lexical retrieval (action naming) and sentence processing (embedded sentences, both subject and object relative clauses). Reaction time was slightly faster on the test of embedded sentences among those with MetS. MetS adversely affects the language performance of older adults, impairing accuracy of both lexical retrieval and sentence processing. This finding reinforces and extends results of earlier research documenting the negative influence of potentially treatable medical conditions (diabetes, hypertension) on language performance in aging. The unanticipated finding that persons with MetS were faster in processing embedded sentences may represent an impairment of timing functions among older individuals with MetS.
MPIGeneNet: Parallel Calculation of Gene Co-Expression Networks on Multicore Clusters.
Gonzalez-Dominguez, Jorge; Martin, Maria J
2017-10-10
In this work we present MPIGeneNet, a parallel tool that applies Pearson's correlation and Random Matrix Theory to construct gene co-expression networks. It is based on the state-of-the-art sequential tool RMTGeneNet, which provides networks with high robustness and sensitivity at the expenses of relatively long runtimes for large scale input datasets. MPIGeneNet returns the same results as RMTGeneNet but improves the memory management, reduces the I/O cost, and accelerates the two most computationally demanding steps of co-expression network construction by exploiting the compute capabilities of common multicore CPU clusters. Our performance evaluation on two different systems using three typical input datasets shows that MPIGeneNet is significantly faster than RMTGeneNet. As an example, our tool is up to 175.41 times faster on a cluster with eight nodes, each one containing two 12-core Intel Haswell processors. Source code of MPIGeneNet, as well as a reference manual, are available at https://sourceforge.net/projects/mpigenenet/.
Time Management in the Operating Room: An Analysis of the Dedicated Minimally Invasive Surgery Suite
Hsiao, Kenneth C.; Machaidze, Zurab
2004-01-01
Background: Dedicated minimally invasive surgery suites are available that contain specialized equipment to facilitate endoscopic surgery. Laparoscopy performed in a general operating room is hampered by the multitude of additional equipment that must be transported into the room. The objective of this study was to compare the preparation times between procedures performed in traditional operating rooms versus dedicated minimally invasive surgery suites to see whether operating room efficiency is improved in the specialized room. Methods: The records of 50 patients who underwent laparoscopic procedures between September 2000 and April 2002 were retrospectively reviewed. Twenty-three patients underwent surgery in a general operating room and 18 patients in an minimally invasive surgery suite. Nine patients were excluded because of cystoscopic procedures undergone prior to laparoscopy. Various time points were recorded from which various time intervals were derived, such as preanesthesia time, anesthesia induction time, and total preparation time. A 2-tailed, unpaired Student t test was used for statistical analysis. Results: The mean preanesthesia time was significantly faster in the minimally invasive surgery suite (12.2 minutes) compared with that in the traditional operating room (17.8 minutes) (P=0.013). Mean anesthesia induction time in the minimally invasive surgery suite (47.5 minutes) was similar to time in the traditional operating room (45.7 minutes) (P=0.734). The average total preparation time for the minimally invasive surgery suite (59.6 minutes) was not significantly faster than that in the general operating room (63.5 minutes) (P=0.481). Conclusion: The amount of time that elapses between the patient entering the room and anesthesia induction is statically shorter in a dedicated minimally invasive surgery suite. Laparoscopic surgery is performed more efficiently in a dedicated minimally invasive surgery suite versus a traditional operating room. PMID:15554269
Rahmani, George; Prats, Jayne; Norchi, Terrence; Kates, Steven; McInerney, Veronica; Woods, Jack; Kelly, Jack
2018-01-29
The self-assembling peptide barrier T45K (SAPB-T45K) is an oligopeptide that rapidly forms a biocompatible hemostatic barrier when applied to wounds. Evaluate safety and performance of SAPB-T45K in cutaneous surgery. In this single-blind study, after sequential shave excision of 2 lesions, wounds were randomized (intrapatient) to SAPB-T45K or control treatment. Safety was assessed at treatment, Day 7, and Day 30. Performance was evaluated using time to hemostasis (TTH) and ASEPSIS wound scores, with a subgroup analysis for patients with or without antiplatelet therapy. Each of 46 patients (10 [22%] with antiplatelet therapy) received randomized SAPB-T45K or control treatment for 2 wounds. Safety assessments were similar, and ASEPSIS scores reflected normal healing in both wound groups. SAPB-T45K demonstrated significantly faster median TTH (24.5 [range, 7-165] seconds) compared with control (44 [10-387] seconds), for a 41% median TTH reduction (18 [95% confidence interval, 7-35] seconds, p < .001). SAPB-T45K provided an identical median TTH of 24 seconds, regardless of antiplatelet therapy. Control median TTH was 90 and 40 seconds for patients taking or not taking antiplatelet therapy, respectively. SAPB-T45K provided significantly faster median TTH versus control, especially with antiplatelet therapy, and safety profiles were similar.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal.
Time to tenure in Spanish universities: an event history analysis.
Sanz-Menéndez, Luis; Cruz-Castro, Laura; Alva, Kenedy
2013-01-01
Understanding how institutional incentives and mechanisms for assigning recognition shape access to a permanent job is important. This study, based on data from questionnaire survey responses and publications of 1,257 university science, biomedical and engineering faculty in Spain, attempts to understand the timing of getting a permanent position and the relevant factors that account for this transition, in the context of dilemmas between mobility and permanence faced by organizations. Using event history analysis, the paper looks at the time to promotion and the effects of some relevant covariates associated to academic performance, social embeddedness and mobility. We find that research productivity contributes to career acceleration, but that other variables are also significantly associated to a faster transition. Factors associated to the social elements of academic life also play a role in reducing the time from PhD graduation to tenure. However, mobility significantly increases the duration of the non-tenure stage. In contrast with previous findings, the role of sex is minor. The variations in the length of time to promotion across different scientific domains is confirmed, with faster career advancement for those in the Engineering and Technological Sciences compared with academics in the Biological and Biomedical Sciences. Results show clear effects of seniority, and rewards to loyalty, in addition to some measurements of performance and quality of the university granting the PhD, as key elements speeding up career advancement. Findings suggest the existence of a system based on granting early permanent jobs to those that combine social embeddedness and team integration with some good credentials regarding past and potential future performance, rather than high levels of mobility.
Time to Tenure in Spanish Universities: An Event History Analysis
Sanz-Menéndez, Luis; Cruz-Castro, Laura; Alva, Kenedy
2013-01-01
Understanding how institutional incentives and mechanisms for assigning recognition shape access to a permanent job is important. This study, based on data from questionnaire survey responses and publications of 1,257 university science, biomedical and engineering faculty in Spain, attempts to understand the timing of getting a permanent position and the relevant factors that account for this transition, in the context of dilemmas between mobility and permanence faced by organizations. Using event history analysis, the paper looks at the time to promotion and the effects of some relevant covariates associated to academic performance, social embeddedness and mobility. We find that research productivity contributes to career acceleration, but that other variables are also significantly associated to a faster transition. Factors associated to the social elements of academic life also play a role in reducing the time from PhD graduation to tenure. However, mobility significantly increases the duration of the non-tenure stage. In contrast with previous findings, the role of sex is minor. The variations in the length of time to promotion across different scientific domains is confirmed, with faster career advancement for those in the Engineering and Technological Sciences compared with academics in the Biological and Biomedical Sciences. Results show clear effects of seniority, and rewards to loyalty, in addition to some measurements of performance and quality of the university granting the PhD, as key elements speeding up career advancement. Findings suggest the existence of a system based on granting early permanent jobs to those that combine social embeddedness and team integration with some good credentials regarding past and potential future performance, rather than high levels of mobility. PMID:24116199
The rate of phosphocreatine hydrolysis and resynthesis in exercising muscle in humans using 31P-MRS.
Yoshida, Takayoshi
2002-09-01
Time-resolved 31-phosphorus nuclear magnetic resonance spectroscopy (31P-MRS) of the biceps femoris muscles was performed during exercise and recovery in six healthy sedentary male subjects (maximal oxygen uptake; 46.6 +/- 1.7 (SEM) ml.kg-1.min-1), 5 male sprinters (56.2 +/- 2.5), and 5 male long-distance runners (73.6 +/- 2.2). Each performed 4 min of knee flexion exercises at absolute values of 1.63 W and 4.90 W, followed by 5 min of recovery in a prone position in a 2.1 T superconducting magnet with a 67 cm bore. 31P-MRS spectra were recorded every 12.8 s during the rest-exercise-recovery sequence. Computer-aided contour analysis and pixel imaging of phosphocreatine peaks (PCr) and inorganic phosphate (Pi) were performed. The work loads in the present study were selected as mild exercise (1.63 W) and heavy exercise (4.90 W), corresponding to 18-23% and 54-70% of maximal exercise intensity. Long-distance runners showed a significantly smaller decrement in PCr and less acidification at a given exercise intensity compared to those shown by sedentary subjects. The transient responses of PCr and Pi during recovery were characterized by first-order kinetics. After exercise, the recovery rates of PCr and Pi were significantly faster in long-distance runners than in sedentary subjects (P < 0.05). Since it is postulated that PCr resynthesis is controlled by aerobic metabolism and mitochondrial creatine kinase, it is suggested that the faster PCr and Pi recovery rates and decreased acidification seen in long-distance runners during and after exercise might be attributed to their greater capacity for aerobic metabolism.
Algorithms of GPU-enabled reactive force field (ReaxFF) molecular dynamics.
Zheng, Mo; Li, Xiaoxia; Guo, Li
2013-04-01
Reactive force field (ReaxFF), a recent and novel bond order potential, allows for reactive molecular dynamics (ReaxFF MD) simulations for modeling larger and more complex molecular systems involving chemical reactions when compared with computation intensive quantum mechanical methods. However, ReaxFF MD can be approximately 10-50 times slower than classical MD due to its explicit modeling of bond forming and breaking, the dynamic charge equilibration at each time-step, and its one order smaller time-step than the classical MD, all of which pose significant computational challenges in simulation capability to reach spatio-temporal scales of nanometers and nanoseconds. The very recent advances of graphics processing unit (GPU) provide not only highly favorable performance for GPU enabled MD programs compared with CPU implementations but also an opportunity to manage with the computing power and memory demanding nature imposed on computer hardware by ReaxFF MD. In this paper, we present the algorithms of GMD-Reax, the first GPU enabled ReaxFF MD program with significantly improved performance surpassing CPU implementations on desktop workstations. The performance of GMD-Reax has been benchmarked on a PC equipped with a NVIDIA C2050 GPU for coal pyrolysis simulation systems with atoms ranging from 1378 to 27,283. GMD-Reax achieved speedups as high as 12 times faster than Duin et al.'s FORTRAN codes in Lammps on 8 CPU cores and 6 times faster than the Lammps' C codes based on PuReMD in terms of the simulation time per time-step averaged over 100 steps. GMD-Reax could be used as a new and efficient computational tool for exploiting very complex molecular reactions via ReaxFF MD simulation on desktop workstations. Copyright © 2013 Elsevier Inc. All rights reserved.
HIA: a genome mapper using hybrid index-based sequence alignment.
Choi, Jongpill; Park, Kiejung; Cho, Seong Beom; Chung, Myungguen
2015-01-01
A number of alignment tools have been developed to align sequencing reads to the human reference genome. The scale of information from next-generation sequencing (NGS) experiments, however, is increasing rapidly. Recent studies based on NGS technology have routinely produced exome or whole-genome sequences from several hundreds or thousands of samples. To accommodate the increasing need of analyzing very large NGS data sets, it is necessary to develop faster, more sensitive and accurate mapping tools. HIA uses two indices, a hash table index and a suffix array index. The hash table performs direct lookup of a q-gram, and the suffix array performs very fast lookup of variable-length strings by exploiting binary search. We observed that combining hash table and suffix array (hybrid index) is much faster than the suffix array method for finding a substring in the reference sequence. Here, we defined the matching region (MR) is a longest common substring between a reference and a read. And, we also defined the candidate alignment regions (CARs) as a list of MRs that is close to each other. The hybrid index is used to find candidate alignment regions (CARs) between a reference and a read. We found that aligning only the unmatched regions in the CAR is much faster than aligning the whole CAR. In benchmark analysis, HIA outperformed in mapping speed compared with the other aligners, without significant loss of mapping accuracy. Our experiments show that the hybrid of hash table and suffix array is useful in terms of speed for mapping NGS sequencing reads to the human reference genome sequence. In conclusion, our tool is appropriate for aligning massive data sets generated by NGS sequencing.
When listening to rain sounds boosts arithmetic ability
De Benedetto, Francesco; Ferrari, Maria Vittoria; Ferrarini, Giorgia
2018-01-01
Studies in the literature have provided conflicting evidence about the effects of background noise or music on concurrent cognitive tasks. Some studies have shown a detrimental effect, while others have shown a beneficial effect of background auditory stimuli. The aim of this study was to investigate the influence of agitating, happy or touching music, as opposed to environmental sounds or silence, on the ability of non-musician subjects to perform arithmetic operations. Fifty university students (25 women and 25 men, 25 introverts and 25 extroverts) volunteered for the study. The participants were administered 180 easy or difficult arithmetic operations (division, multiplication, subtraction and addition) while listening to heavy rain sounds, silence or classical music. Silence was detrimental when participants were faced with difficult arithmetic operations, as it was associated with significantly worse accuracy and slower RTs than music or rain sound conditions. This finding suggests that the benefit of background stimulation was not music-specific but possibly due to an enhanced cerebral alertness level induced by the auditory stimulation. Introverts were always faster than extroverts in solving mathematical problems, except when the latter performed calculations accompanied by the sound of heavy rain, a condition that made them as fast as introverts. While the background auditory stimuli had no effect on the arithmetic ability of either group in the easy condition, it strongly affected extroverts in the difficult condition, with RTs being faster during agitating or joyful music as well as rain sounds, compared to the silent condition. For introverts, agitating music was associated with faster response times than the silent condition. This group difference may be explained on the basis of the notion that introverts have a generally higher arousal level compared to extroverts and would therefore benefit less from the background auditory stimuli. PMID:29466472
Hand grip strength and dexterity function in children aged 6-12 years: A cross-sectional study.
Omar, Mohammed T A; Alghadir, Ahmad H; Zafar, Hamayun; Al Baker, Shaheerah
Cross-sectional and clinical measurement. Assessment of hand function considers an essential part in clinical practice. To develop normative values of hand grip strength and dexterity function for 6-12-year-old children in Saudi Arabia. Grip strength and dexterity function was measured in 525 children using Grip Track hand dynamometer (JTECH Medical, Midvale, UT, USA) and 9-hole pegboard test respectively. The grip strength and dexterity function was improved as age progressed regardless of gender. Across all age groups, the hand grip strength of boys was significantly higher than girls for dominant hand (31.75 ± 10.33 vs 28.24 ± 9.35; P < .001) and nondominant hand (31.01 ± 10.27 vs 27.27 ± 9.30; P < .001). The girls performed slightly faster than boys for dominant hand (19.70 vs 20.68; P < .05) and nondominant hand (21.79 vs 23.46; P < .05). In general, girls completed a 9-HPT faster than boys in the 2 of 7 age groups: 11 years (9-HPT scores = 2.10 seconds; P < .01) and 12 years (9-HPT scores = 1.93 seconds; P < .01). The overall patterns of hand grip strength and dexterity function observed in the present study are similar to the previous studies that established acceleration of grip strength with advanced age, and faster performance scores in older children than younger children in both genders. Norms of hand grip strength and dexterity enable therapists to identify some developmental characteristics of hand function among Saudi children, determine the presence of impairment, and compare scores from children in different clinical settings. Not applicable. Copyright © 2017 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.
When listening to rain sounds boosts arithmetic ability.
Proverbio, Alice Mado; De Benedetto, Francesco; Ferrari, Maria Vittoria; Ferrarini, Giorgia
2018-01-01
Studies in the literature have provided conflicting evidence about the effects of background noise or music on concurrent cognitive tasks. Some studies have shown a detrimental effect, while others have shown a beneficial effect of background auditory stimuli. The aim of this study was to investigate the influence of agitating, happy or touching music, as opposed to environmental sounds or silence, on the ability of non-musician subjects to perform arithmetic operations. Fifty university students (25 women and 25 men, 25 introverts and 25 extroverts) volunteered for the study. The participants were administered 180 easy or difficult arithmetic operations (division, multiplication, subtraction and addition) while listening to heavy rain sounds, silence or classical music. Silence was detrimental when participants were faced with difficult arithmetic operations, as it was associated with significantly worse accuracy and slower RTs than music or rain sound conditions. This finding suggests that the benefit of background stimulation was not music-specific but possibly due to an enhanced cerebral alertness level induced by the auditory stimulation. Introverts were always faster than extroverts in solving mathematical problems, except when the latter performed calculations accompanied by the sound of heavy rain, a condition that made them as fast as introverts. While the background auditory stimuli had no effect on the arithmetic ability of either group in the easy condition, it strongly affected extroverts in the difficult condition, with RTs being faster during agitating or joyful music as well as rain sounds, compared to the silent condition. For introverts, agitating music was associated with faster response times than the silent condition. This group difference may be explained on the basis of the notion that introverts have a generally higher arousal level compared to extroverts and would therefore benefit less from the background auditory stimuli.
Visual performance for trip hazard detection when using incandescent and led miner cap lamps.
Sammarco, John J; Gallagher, Sean; Reyes, Miguel
2010-04-01
Accident data for 2003-2007 indicate that slip, trip, and falls (STFs) are the second leading accident class (17.8%, n=2,441) of lost-time injuries in underground mining. Proper lighting plays a critical role in enabling miners to detect STF hazards in this environment. Often, the only lighting available to the miner is from a cap lamp worn on the miner's helmet. The focus of this research was to determine if the spectral content of light from light-emitting diode (LED) cap lamps enabled visual performance improvements for the detection of tripping hazards as compared to incandescent cap lamps that are traditionally used in underground mining. A secondary objective was to determine the effects of aging on visual performance. The visual performance of 30 subjects was quantified by measuring each subject's speed and accuracy in detecting objects positioned on the floor both in the near field, at 1.83 meters, and far field, at 3.66 meters. Near field objects were positioned at 0 degrees and +/-20 degrees off axis, while far field objects were positioned at 0 degrees and +/-10 degrees off axis. Three age groups were designated: group A consisted of subjects 18 to 25 years old, group B consisted of subjects 40 to 50 years old, and group C consisted of subjects 51 years and older. Results of the visual performance comparison for a commercially available LED, a prototype LED, and an incandescent cap lamp indicate that the location of objects on the floor, the type of cap lamp used, and subject age all had significant influences on the time required to identify potential trip hazards. The LED-based cap lamps enabled detection times that were an average of 0.96 seconds faster compared to the incandescent cap lamp. Use of the LED cap lamps resulted in average detection times that were about 13.6% faster than those recorded for the incandescent cap lamp. The visual performance differences between the commercially available LED and prototype LED cap lamp were not statistically significant. It can be inferred from this data that the spectral content from LED-based cap lamps could enable significant visual performance improvements for miners in the detection of trip hazards. Published by Elsevier Ltd.
MacNeill, Leigha A; Ram, Nilam; Bell, Martha Ann; Fox, Nathan A; Pérez-Edgar, Koraly
2018-05-01
This study examined how timing (i.e., relative maturity) and rate (i.e., how quickly infants attain proficiency) of A-not-B performance were related to changes in brain activity from age 6 to 12 months. A-not-B performance and resting EEG (electroencephalography) were measured monthly from age 6 to 12 months in 28 infants and were modeled using logistic and linear growth curve models. Infants with faster performance rates reached performance milestones earlier. Infants with faster rates of increase in A-not-B performance had lower occipital power at 6 months and greater linear increases in occipital power. The results underscore the importance of considering nonlinear change processes for studying infants' cognitive development as well as how these changes are related to trajectories of EEG power. © 2018 The Authors. Child Development © 2018 Society for Research in Child Development, Inc.
Modular socket system versus traditionally laminated socket: a cost analysis.
Normann, Elna; Olsson, Anna; Brodtkorb, Thor-Henrik
2011-03-01
Using the new modular socket system (MSS) to produce a prosthetic socket directly on the patient has the potential of being easier and quicker to manufacture but also incurring higher costs. The purpose of the study was to compare the costs of manufacturing a transtibial prosthetic socket using either a MSS or a standard laminated socket (PC). Concurrent controlled trial. A total of 20 patients at two orthopaedic facilities were followed with regards to the cost of manufacturing a prosthetic socket using either MSS or PC. Time aspects and material costs were considered in the cost analysis. Other factors studied include delivery time and number of visits. For the cost analysis, only direct costs pertaining to the prosthetic socket were considered. The total cost of MSS was found to be significantly higher (p < 0.01) compared to PC. However, the production and time cost was significantly lower. Delivery time to the patient was 1 day for MSS compared to 17 days for PC. Our study shows that the direct prosthetic cost of treating a patient using MSS is significantly higher than treating a patient using PC. However, the MSS prosthesis can be delivered significantly faster and with fewer visits. Further studies taking the full societal costs of MSS into account should therefore be performed. This study shows that the direct prosthetic cost of treating a patient with Modular Socket System is significantly higher than treating a patient with plastercasting with standard laminated socket. However, the Modular Socket System prosthesis can be delivered significantly faster and with fewer visits.
Mistry, Freddy Kersi; Hegde, Nidarsh Diwakar; Hegde, Mithra Nidarsh
2016-01-01
One of the most critical and crucial steps in surgical extraction is cutting the bone or osteotomy, for which many techniques are used, e.g., chisels and mallet, rotary instruments, and ultrasound bone-cutting instruments. If they are not used judiciously, they can be hazardous. To assess the efficiency of piezosurgery unit over micromotor while performing surgical extraction of lower third molars by assessing the time taken for the surgery and measuring postoperative parameters such as pain, trismus, and swelling. Thirty patients having bilateral impacted third molars with the same difficulty index were selected for the study. One side surgical removal was done using micromotor and other side by piezosurgery with an interval of 15 days. After each surgery, time taken to finish was measured and patients were followed up on postoperative days 1, 3, 5, 7, and 15 for assessing pain, trismus, and swelling. Data obtained were statistically analyzed. The mean time taken for the micromotor group is 37.90 min whereas by the piezosurgery group is 54.63 min, showing a statistically significant difference ( P < 0.001). Furthermore, there is statistically significant difference ( P < 0.001) in the level of pain, trismus, and swelling on postoperative days 1, 3, 5, and 7. Even the intragroup comparison of piezosurgical group for trismus and swelling showed no statistically significant difference on postoperative day 7, indicating faster recovery of trismus and swelling. On postoperative day 15, there was no difference in any parameter in both groups indicating complete symptom-free recovery in both groups. It takes more time to perform surgical extraction of third molars when piezosurgical unit is used. Despite that, it causes less pain postoperatively with faster improvement in trismus and quicker reduction in swelling.
Postsurgical consequences in lower third molar surgical extraction using micromotor and piezosurgery
Mistry, Freddy Kersi; Hegde, Nidarsh Diwakar; Hegde, Mithra Nidarsh
2016-01-01
Background: One of the most critical and crucial steps in surgical extraction is cutting the bone or osteotomy, for which many techniques are used, e.g., chisels and mallet, rotary instruments, and ultrasound bone-cutting instruments. If they are not used judiciously, they can be hazardous. Objectives: To assess the efficiency of piezosurgery unit over micromotor while performing surgical extraction of lower third molars by assessing the time taken for the surgery and measuring postoperative parameters such as pain, trismus, and swelling. Materials and Methods: Thirty patients having bilateral impacted third molars with the same difficulty index were selected for the study. One side surgical removal was done using micromotor and other side by piezosurgery with an interval of 15 days. After each surgery, time taken to finish was measured and patients were followed up on postoperative days 1, 3, 5, 7, and 15 for assessing pain, trismus, and swelling. Data obtained were statistically analyzed. Results: The mean time taken for the micromotor group is 37.90 min whereas by the piezosurgery group is 54.63 min, showing a statistically significant difference (P < 0.001). Furthermore, there is statistically significant difference (P < 0.001) in the level of pain, trismus, and swelling on postoperative days 1, 3, 5, and 7. Even the intragroup comparison of piezosurgical group for trismus and swelling showed no statistically significant difference on postoperative day 7, indicating faster recovery of trismus and swelling. On postoperative day 15, there was no difference in any parameter in both groups indicating complete symptom-free recovery in both groups. Conclusion: It takes more time to perform surgical extraction of third molars when piezosurgical unit is used. Despite that, it causes less pain postoperatively with faster improvement in trismus and quicker reduction in swelling. PMID:28299267
Faster self-paced rate of drinking for alcohol mixed with energy drinks versus alcohol alone.
Marczinski, Cecile A; Fillmore, Mark T; Maloney, Sarah F; Stamates, Amy L
2017-03-01
The consumption of alcohol mixed with energy drinks (AmED) has been associated with higher rates of binge drinking and impaired driving when compared with alcohol alone. However, it remains unclear why the risks of use of AmED are heightened compared with alcohol alone even when the doses of alcohol consumed are similar. Therefore, the purpose of this laboratory study was to investigate if the rate of self-paced beverage consumption was faster for a dose of AmED versus alcohol alone using a double-blind, within-subjects, placebo-controlled study design. Participants (n = 16) of equal gender who were social drinkers attended 4 separate test sessions that involved consumption of alcohol (1.97 ml/kg vodka) and energy drinks, alone and in combination. On each test day, the dose assigned was divided into 10 cups. Participants were informed that they would have a 2-h period to consume the 10 drinks. After the self-paced drinking period, participants completed a cued go/no-go reaction time (RT) task and subjective ratings of stimulation and sedation. The results indicated that participants consumed the AmED dose significantly faster (by ∼16 min) than the alcohol dose. For the performance task, participants' mean RTs were slower in the alcohol conditions and faster in the energy-drink conditions. In conclusion, alcohol consumers should be made aware that rapid drinking might occur for AmED beverages, thus heightening alcohol-related safety risks. The fast rate of drinking may be related to the generalized speeding of responses after energy-drink consumption. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
The repeated-bout effect: influence on biceps brachii oxygenation and myoelectrical activity.
Muthalib, Makii; Lee, Hoseong; Millet, Guillaume Y; Ferrari, Marco; Nosaka, Kazunori
2011-05-01
This study investigated biceps brachii oxygenation and myoelectrical activity during and following maximal eccentric exercise to better understand the repeated-bout effect. Ten men performed two bouts of eccentric exercise (ECC1, ECC2), consisting of 10 sets of 6 maximal lengthening contractions of the elbow flexors separated by 4 wk. Tissue oxygenation index minimum amplitude (TOI(min)), mean and maximum total hemoglobin volume by near-infrared spectroscopy, torque, and surface electromyography root mean square (EMG(RMS)) during exercise were compared between ECC1 and ECC2. Changes in maximal voluntary isometric contraction (MVC) torque, range of motion, plasma creatine kinase activity, muscle soreness, TOI(min), and EMG(RMS) during sustained (10-s) and 30-repeated isometric contraction tasks at 30% (same absolute force) and 100% MVC (same relative force) for 4 days postexercise were compared between ECC1 and ECC2. No significant differences between ECC1 and ECC2 were evident for changes in torque, TOI(min), mean total hemoglobin volume, maximum total hemoglobin volume, and EMG(RMS) during exercise. Smaller (P < 0.05) changes and faster recovery of muscle damage markers were evident following ECC2 than ECC1. During 30% MVC tasks, TOI(min) did not change, but EMG(RMS) increased 1-4 days following ECC1 and ECC2. During 100% MVC tasks, EMG(RMS) did not change, but torque and TOI(min) decreased 1-4 days following ECC1 and ECC2. TOI(min) during 100% MVC tasks and EMG(RMS) during 30% MVC tasks recovered faster (P < 0.05) following ECC2 than ECC1. We conclude that the repeated-bout effect cannot be explained by altered muscle activation or metabolic/hemodynamic changes, and the faster recovery in muscle oxygenation and activation was mainly due to faster recovery of force.
Maie, Takashi; Wilson, Megan P; Schoenfuss, Heiko L; Blob, Richard W
2009-03-01
Distributions of Hawaiian stream fishes are typically interrupted by waterfalls that divide streams into multiple segments. Larvae hatch upstream, are flushed into the ocean, and must climb these waterfalls to reach adult habitats when returning back to freshwater as part of an amphidromous life cycle. Stream surveys and studies of climbing performance show that Lentipes concolor Gill can reach fast-flowing upper stream segments but that Awaous guamensis Valenciennes reaches only slower, lower stream segments. Gut content analyses for these two species indicate considerable overlap in diet, suggesting that feeding kinematics and performance of these two species might be comparable. Alternatively, feeding kinematics and performance of these species might be expected to differ in relation to the different flow regimes in their habitat (feeding in faster stream currents for L. concolor versus in slower currents for A. guamensis). To test these alternative hypotheses, we compared food capturing kinematics and performance during suction feeding behaviors of A. guamensis and L. concolor using morphological data and high-speed video. Lentipes concolor showed both a significantly larger gape angle and faster jaw opening than A. guamensis. Geometric models calculated that despite the inverse relationship of gape size and suction pressure generation, the fast jaw motions of L. concolor allow it to achieve higher pressure differentials than A. guamensis. Such elevated suction pressure would enhance the ability of L. concolor to successfully capture food in the fast stream reaches it typically inhabits. Differences in jaw morphology may contribute to these differences in performance, as the lever ratio for jaw opening is about 10% lower in L. concolor compared with A. guamensis, suiting the jaws of L. concolor better for fast opening. Copyright 2008 Wiley-Liss, Inc.
A comparison of microwave versus direct solar heating for lunar brick production
NASA Technical Reports Server (NTRS)
Yankee, S. J.; Strenski, D. G.; Pletka, B. J.; Patil, D. S.; Mutsuddy, B. C.
1990-01-01
Two processing techniques considered suitable for producing bricks from lunar regolith are examined: direct solar heating and microwave heating. An analysis was performed to compare the two processes in terms of the amount of power and time required to fabricate bricks of various sizes. Microwave heating was shown to be significantly faster than solar heating for rapid production of realistic-size bricks. However, the relative simplicity of the solar collector(s) used for the solar furnace compared to the equipment necessary for microwave generation may present an economic tradeoff.
A comparison of two central difference schemes for solving the Navier-Stokes equations
NASA Technical Reports Server (NTRS)
Maksymiuk, C. M.; Swanson, R. C.; Pulliam, T. H.
1990-01-01
Five viscous transonic airfoil cases were computed by two significantly different computational fluid dynamics codes: An explicit finite-volume algorithm with multigrid, and an implicit finite-difference approximate-factorization method with Eigenvector diagonalization. Both methods are described in detail, and their performance on the test cases is compared. The codes utilized the same grids, turbulence model, and computer to provide the truest test of the algorithms. The two approaches produce very similar results, which, for attached flows, also agree well with experimental results; however, the explicit code is considerably faster.
Lee, Sang-Uk; Chung, Yang-Guk; Kim, Seok-Jung; Oh, Il-Hoan; Kim, Yong-Sik; Ju, Sung-Hun
2014-02-01
We study the efficacy of bone regeneration by using two differently sized allogeneic cancellous bone granules loaded with autologous cultured osteoblasts in a rabbit model. Critical-sized bone defects of the radial shaft were made in 40 New Zealand White rabbits. Small allogeneic bone granules (150-300 μm in diameter) loaded with cultured differentiated autologous osteoblasts were implanted into one forearm (SBG group) and large bone granules (500-710 μm) loaded with osteoblasts were implanted into the forearm of the other side (LBG group). Radiographic evaluations were performed at 3, 6, 9 and 12 weeks and histology and micro-CT image analysis were carried out at 6 and 12 weeks post-implantation. On radiographic evaluation, the LBG group showed a higher bone quantity index at 3 and 6 weeks post-implantation (P < 0.05) but statistical significance was lost at 9 and 12 weeks. The progression of biological processes of the SBG group was faster than that of the LBG group. On micro-CT image analysis, the LBG group revealed a higher total bone volume and surface area than the SBG group at 6 weeks (P < 0.05) but the difference decreased at 12 weeks and was without statistical significance. Histological evaluation also revealed faster progression of new bone formation and maturation in the SBG group. Thus, the two differently sized allogeneic bone granules loaded with co-cultured autologous osteoblasts show no differences in the amount of bone regeneration, although the SBG group exhibits faster progression of bone regeneration and remodeling. This method might therefore provide benefits, such as a short healing time and easy application in an injectable form, in a clinical setting.
NASA Astrophysics Data System (ADS)
Yang, Liqin; Sang, Nong; Gao, Changxin
2018-03-01
Vehicle parts detection plays an important role in public transportation safety and mobility. The detection of vehicle parts is to detect the position of each vehicle part. We propose a new approach by combining Faster RCNN and three level cascaded convolutional neural network (DCNN). The output of Faster RCNN is a series of bounding boxes with coordinate information, from which we can locate vehicle parts. DCNN can precisely predict feature point position, which is the center of vehicle part. We design an output strategy by combining these two results. There are two advantages for this. The quality of the bounding boxes are greatly improved, which means vehicle parts feature point position can be located more precise. Meanwhile we preserve the position relationship between vehicle parts and effectively improve the validity and reliability of the result. By using our algorithm, the performance of the vehicle parts detection improve obviously compared with Faster RCNN.
Linking mind wandering tendency to risky driving in young male drivers.
Albert, Derek A; Ouimet, Marie Claude; Jarret, Julien; Cloutier, Marie-Soleil; Paquette, Martin; Badeau, Nancy; Brown, Thomas G
2018-02-01
Risky driving is a significant contributor to road traffic crashes, especially in young drivers. Transient mind wandering states, an internal form of distraction, are associated with faster driving, reduced headway distance, slower response times, reduced driver vigilance, and increased crash risk. It is unclear whether a trait tendency to mind wander predicts risky driving, however. Mind wandering is also associated with poor executive control, but whether this capacity moderates the putative link between mind wandering tendency and risky driving is uncertain. The present study tested whether mind wandering tendency predicts risky driving behaviour in young male drivers aged 18-21 (N=30) and whether this relationship is mediated by driver vigilance and moderated by executive control capacity. Mind wandering was measured with the Sustained Attention to Response Task (SART) and the Daydreaming Frequency Scale (DDFS). Risky driving was assessed by mean speed in a driving simulator and driver vigilance was quantified by horizontal eye movements measured with eye tracking. Results showed that greater mind wandering tendency based on SART performance significantly predicts faster mean speed, confirming the main hypothesis. Neither driver vigilance mediated nor executive control capacity moderated this relationship as hypothesized. These findings speak to the complexity of individual differences in mind wandering. Overall, mind wandering tendency is a significant marker of risky driving in young drivers, which could guide the development of targeted interventions. Copyright © 2017 Elsevier Ltd. All rights reserved.
Kinetic release of hydrogen peroxide from different whitening products.
da Silva Marques, Duarte Nuno; Silveira, Joao Miguel; Marques, Joana Rita; Amaral, Joao Almeida; Guilherme, Nuno Marques; da Mata, António Duarte
2012-01-01
The objective of this in vitro study was to evaluate the kinetics of hydrogen peroxide (HP) release from five different bleaching products: VivaStyle® 10% fitted tray gel, VivaStyle® 30% in-office bleaching gel, VivaStyle® Paint-On Plus paint-on bleaching varnish, Opalescence PF® 10% carbamide peroxide gel and Trèswhite Supreme 10% HP gel. Each product was firstly titrated for its HP content by a described method. HP release kinetics was assessed by a modified spectrophotometric technique. One sample t test was performed to test for differences between the manufacturers' claimed HP concentrations and the titrated HP content in the whitening products. Analysis of variance plus Tamhane's post hoc tests and Pearson correlation analysis were used as appropriate. Values of P < 0.05 were taken as significant. Titrated HP revealed an increased content when compared to the manufacturer's specifications for all the products tested (P < 0.05), although only products from one manufacturer produced significantly higher results. All products presented a significant (P < 0.05) and sustained release of HP. However, the product with paint-on cellulose-based matrix resulted in significantly (P < 0.05) faster kinetics when compared to other products tested. These results are consistent with manufacturers' reduced recommended application times. The results of this study suggest that modifying the matrix composition may be a viable alternative to HP concentration increase, since this may result in faster release kinetics without exposure to high HP concentrations.
Binary mesh partitioning for cache-efficient visualization.
Tchiboukdjian, Marc; Danjean, Vincent; Raffin, Bruno
2010-01-01
One important bottleneck when visualizing large data sets is the data transfer between processor and memory. Cache-aware (CA) and cache-oblivious (CO) algorithms take into consideration the memory hierarchy to design cache efficient algorithms. CO approaches have the advantage to adapt to unknown and varying memory hierarchies. Recent CA and CO algorithms developed for 3D mesh layouts significantly improve performance of previous approaches, but they lack of theoretical performance guarantees. We present in this paper a {\\schmi O}(N\\log N) algorithm to compute a CO layout for unstructured but well shaped meshes. We prove that a coherent traversal of a N-size mesh in dimension d induces less than N/B+{\\schmi O}(N/M;{1/d}) cache-misses where B and M are the block size and the cache size, respectively. Experiments show that our layout computation is faster and significantly less memory consuming than the best known CO algorithm. Performance is comparable to this algorithm for classical visualization algorithm access patterns, or better when the BSP tree produced while computing the layout is used as an acceleration data structure adjusted to the layout. We also show that cache oblivious approaches lead to significant performance increases on recent GPU architectures.
Ko, Dae-Sik; Jung, Dae-In; Jeong, Mi-Ae
2014-11-01
[Purpose] The aim of the present study was to investigate the effects of core stability exercise (CSE) on the physical and psychological functions of elderly women while negotiating general obstacles. [Subjects and Methods] After allocating 10 elderly women each to the core stability training group and the control group, we carried out Performance-Oriented Mobility Assessment (POMA) and measured crossing velocity (CV), maximum vertical heel clearance (MVHC), and knee flexion angle for assessing physical performances. We evaluated depression and fear of falling for assessing psychological functions. [Results] Relative to the control group, the core stability training group showed statistically significant overall changes after the training session: an increase in POMA scores, faster CV, lower MVHC, and a decrease in knee flexion angle. Furthermore, depression and fear of falling decreased significantly. [Conclusion] CSE can have a positive effect on the improvement of physical and psychological performances of older women who are vulnerable to falls as they negotiate everyday obstacles.
Sentinel lymph node accumulation of Lymphoseek and Tc-99m-sulfur colloid using a “2-day” protocol☆
Wallace, Anne M.; Hoh, Carl K.; Limmer, Karl K.; Darrah, Denise D.; Schulteis, Gery; Vera, David R.
2014-01-01
Lymphoseek is a receptor-binding radiopharmaceutical specifically designed for sentinel lymph node (SLN) mapping. We conducted a clinical trial which measured the injection site clearance and sentinel lymph node accumulation after a single intradermal injection of Lymphoseek or unfiltered [99mTc]sulfur colloid (TcSC) using a “2-day” protocol for SLN mapping of breast cancer. Eleven patients with breast cancer participated in this study. Five patients received an intradermal administration of 1.0 nmol of 99mTc-labeled Lymphoseek; SLN mapping was performed on four subjects within 19 to 27 h. Six subjects received an intradermal administration of TcSC; SLN mapping was performed on five subjects within 18 to 26 h. Lymphoseek exhibited a significantly (P<.001) faster injection site clearance than TcSC. The mean Lymphoseek clearance half-time was 2.18±1.09 h compared to 57.4±92.8 h for TcSC. The mean sentinel lymph node uptake of Lymphoseek (1.5±1.7%) and TcSC (3.5±3.1%) was statistically equivalent (P=.213). When an intradermal injection is employed, Lymphoseek demonstrated faster injection site clearance than unfiltered [99mTc]sulfur colloid and persistent SLN accumulation for at least 24 h. PMID:19647175
Physiological characteristics of elite short- and long-distance triathletes.
Millet, Grégoire P; Dréano, Patrick; Bentley, David J
2003-01-01
The purpose of this study was to compare the physiological responses in cycling and running of elite short-distance (ShD) and long-distance (LD) triathletes. Fifteen elite male triathletes participating in the World Championships were divided into two groups (ShD and LD) and performed a laboratory trial that comprised submaximal treadmill running, maximal then submaximal ergometry cycling and then an additional submaximal run. "In situ" best ShD triathlon performances were also analysed for each athlete. ShD demonstrated a significantly faster swim time than LD whereas .VO(2max) (ml kg(-1) min(-1)), cycling economy (W l(-1) min(-1)), peak power output (.W(peak),W) and ventilatory threshold (%.VO(2max)) were all similar between ShD and LD. Moreover, there were no differences between the two groups in the change (%) in running economy from the first to the second running bout. Swimming time was correlated to .W(peak)(r=-0.76; P<0.05) and economy ( r=-0.89; P<0.01) in the ShD athletes. Also, cycling time in the triathlon was correlated to .W(peak)(r=-0.83; P<0.05) in LD. In conclusion, ShD triathletes had a faster swimming time but did not exhibit different maximal or submaximal physiological characteristics measured in cycling and running than LD triathletes.
Chen, Hui-Ya; Chang, Hsiao-Yun; Ju, Yan-Ying; Tsao, Hung-Ting
2017-06-01
Rhythmic gymnasts specialise in dynamic balance under sensory conditions of numerous somatosensory, visual, and vestibular stimulations. This study investigated whether adolescent rhythmic gymnasts are superior to peers in Sensory Organisation test (SOT) performance, which quantifies the ability to maintain standing balance in six sensory conditions, and explored whether they plateaued faster during familiarisation with the SOT. Three and six sessions of SOTs were administered to 15 female rhythmic gymnasts (15.0 ± 1.8 years) and matched peers (15.1 ± 2.1 years), respectively. The gymnasts were superior to their peers in terms of fitness measures, and their performance was better in the SOT equilibrium score when visual information was unreliable. The SOT learning effects were shown in more challenging sensory conditions between Sessions 1 and 2 and were equivalent in both groups; however, over time, the gymnasts gained marginally significant better visual ability and relied less on visual sense when unreliable. In conclusion, adolescent rhythmic gymnasts have generally the same sensory organisation ability and learning rates as their peers. However, when visual information is unreliable, they have superior sensory organisation ability and learn faster to rely less on visual sense.
ERIC Educational Resources Information Center
Scriven, Michael
2011-01-01
In this paper, the author talks about Faster Forward Fund (3F). The basic idea of 3F is to provide support for three approaches within the evaluation field that are not the main foci of AEA activities, or of any other organization as far as is known: (1) to develop ideas that show promise for significantly accelerating the theory or practice of…
Full suspension mountain bike improves off-road cycling performance.
Nishii, T; Umemura, Y; Kitagawa, K
2004-12-01
The purpose of the present study was to determine the effects of suspension systems on the cycling performance of cyclists during off-road bicycling. Eight elite male cyclists (67.8+/-5.8 ml/min/kg of (.-)VO(2max)) performed 30-minute riding tests on bicycles with 2 different suspension setups: front suspension (FS) and front and rear suspension (FRS). Heart rate, blood lactate concentration, pedaling power, cadence, cycling velocity, and completed distance during the trial were measured creatin kinase (CK), lactic dehydrogenase (LDH) and glutamic-oxaloacetic transaminase (GOT) were measured before and after the trials. The average cadence during the trial was significantly higher (p<0.05) with the FRS (73.6+/-6.1 rpm) than the FS (70.2+/-6.2 rpm). Subjects rode significantly faster (p<0.05) on FRS (24.1+/-2.6 km/h) than FS bikes (22.9+/-2.4 km/h), although no significant difference was observed in pedaling power (240.7+/-26.6 W vs 242.2+/-28.8 W, FS vs FRS, respectively). Serum creatin kinase increased significantly (p<0.05) at 24 h after the trial when cyclists exercised with the FS bike. We conclude that the FRS improved cycling performance over rough terrain. FRS might therefore be more suitable for cross-country mountain bike races.
Latham, Daniel T; Hill, Grant M; Petray, Clayre K
2013-04-01
The purpose of this study was to assess whether a treadmill mile is an acceptable FitnessGram Test substitute for the traditional one-mile run for middle school boys and girls. Peak heart rate and perceived physical exertion of the participants were also measured to assess students' effort. 48 boys and 40 girls participated, with approximately 85% classified as Hispanic. Boys' mean time for the traditional one-mile run, as well as peak heart rate and perceived exertion, were statistically significantly faster and higher, respectively, than for the treadmill mile. Girls' treadmill mile times were not statistically significantly different from the traditional one-mile run. There were no statistically significant differences for girl's peak heart rate or perceived exertion. The results suggest that providing middle school students a choice of completing the FitnessGram mile run in either traditional one-mile run or treadmill one-mile format may positively affect performance.
Thomaier, Lauren; Orlando, Megan; Abernethy, Melinda; Paka, Chandhana; Chen, Chi Chiung Grace
2017-08-01
Although surgical simulation provides an effective supplement to traditional training, it is not known whether skills are transferable between minimally invasive surgical modalities. The purpose of this study was to assess the transferability of skills between minimally invasive surgical simulation platforms among simulation-naïve participants. Forty simulation-naïve medical students were enrolled in this randomized single-blinded controlled trial. Participants completed a baseline evaluation on laparoscopic (Fundamentals of Laparoscopic Surgery Program, Los Angeles, CA) and robotic (dV-Trainer, Mimic, Seattle, WA) simulation peg transfer tasks. Participants were then randomized to perform a practice session on either the robotic (N = 20) or laparoscopic (N = 20) simulator. Two blinded, expert minimally invasive surgeons evaluated participants before and after training using a modified previously validated subjective global rating scale. Objective measures including time to task completion and Mimic dV-Trainer motion metrics were also recorded. At baseline, there were no significant differences between the training groups as measured by objective and subjective measures for either simulation task. After training, participants randomized to the laparoscopic practice group completed the laparoscopic task faster (p < 0.003) and with higher global rating scale scores (p < 0.001) than the robotic group. Robotic-trained participants performed the robotic task faster (p < 0.001), with improved economy of motion (p < 0.001), and with higher global rating scale scores (p = 0.006) than the laparoscopic group. The robotic practice group also demonstrated significantly improved performance on the laparoscopic task (p = 0.02). Laparoscopic-trained participants also improved their robotic performance (p = 0.02), though the robotic group had a higher percent improvement on the robotic task (p = 0.037). Skills acquired through practice on either laparoscopic or robotic simulation platforms appear to be transferable between modalities. However, participants demonstrate superior skill in the modality in which they specifically train.
Anaerobic capacity of the upper arms in top-level team handball players.
Kounalakis, Stylianos N; Bayios, Ioannis A; Koskolou, Maria D; Geladas, Nickos D
2008-09-01
Handball is a sport with high anaerobic demands in lower body as has been indicated by Wingate test (WT) performed with the legs, but there are no data available concerning power production during a WT performed with the arms in handball players (HndP). Therefore, the purpose of this study was to explore the arm anaerobic profile of HndP during a WT. Twenty-one elite HndP and 9 physical education students (CON), performed a 30-s arm WT. Power production and muscle oxygenation were recorded. Peak power (PP) as well as mean power (MP) was higher (P = .017 and 0.03, and ES = 1.00 and 0.86, respectively) for HndP (HndP PP: 7.6 +/- 0.8 W x kg(-1); CON PP: 6.7 +/- 1.1 W x kg(-1); HndP MP 5.3 +/- 0.6 W x kg(-1); CON MP 4.7 +/- 0.9 W x kg(-1)) with no significant difference in fatigue index between the two groups. Muscle oxygen saturation (StO2) declined approximately 30% with exercise with no differences between groups. During recovery the HndP group had higher StO2 (P = .01, ES= 3.04), total hemoglobin and oxygenated hemoglobin compared with the CON group (P < .01 ES = 3.29 and 0.99, respectively). StO2 returned to resting values in 29.5 +/- 2.3 s in HndP, whereas this variable did not recover after 2 min in CON. The arm anaerobic capacity of the HndP was "excellent," significantly higher than that by the control group. Moreover, HndP exhibited faster recovery of StO2 compared with the control group. The greater power output and the faster muscle reoxygenation of arms in HndP can be attributed to specific training adaptations related to high performance in handball.
Improved knowledge diffusion model based on the collaboration hypernetwork
NASA Astrophysics Data System (ADS)
Wang, Jiang-Pan; Guo, Qiang; Yang, Guang-Yong; Liu, Jian-Guo
2015-06-01
The process for absorbing knowledge becomes an essential element for innovation in firms and in adapting to changes in the competitive environment. In this paper, we present an improved knowledge diffusion hypernetwork (IKDH) model based on the idea that knowledge will spread from the target node to all its neighbors in terms of the hyperedge and knowledge stock. We apply the average knowledge stock V(t) , the variable σ2(t) , and the variance coefficient c(t) to evaluate the performance of knowledge diffusion. By analyzing different knowledge diffusion ways, selection ways of the highly knowledgeable nodes, hypernetwork sizes and hypernetwork structures for the performance of knowledge diffusion, results show that the diffusion speed of IKDH model is 3.64 times faster than that of traditional knowledge diffusion (TKDH) model. Besides, it is three times faster to diffuse knowledge by randomly selecting "expert" nodes than that by selecting large-hyperdegree nodes as "expert" nodes. Furthermore, either the closer network structure or smaller network size results in the faster knowledge diffusion.
Study of data I/O performance on distributed disk system in mask data preparation
NASA Astrophysics Data System (ADS)
Ohara, Shuichiro; Odaira, Hiroyuki; Chikanaga, Tomoyuki; Hamaji, Masakazu; Yoshioka, Yasuharu
2010-09-01
Data volume is getting larger every day in Mask Data Preparation (MDP). In the meantime, faster data handling is always required. MDP flow typically introduces Distributed Processing (DP) system to realize the demand because using hundreds of CPU is a reasonable solution. However, even if the number of CPU were increased, the throughput might be saturated because hard disk I/O and network speeds could be bottlenecks. So, MDP needs to invest a lot of money to not only hundreds of CPU but also storage and a network device which make the throughput faster. NCS would like to introduce new distributed processing system which is called "NDE". NDE could be a distributed disk system which makes the throughput faster without investing a lot of money because it is designed to use multiple conventional hard drives appropriately over network. NCS studies I/O performance with OASIS® data format on NDE which contributes to realize the high throughput in this paper.
NASA Technical Reports Server (NTRS)
Hopkins, W. D.; Washburn, D. A.; Hyatt, C. W.; Rumbaugh, D. M. (Principal Investigator)
1996-01-01
This study describes video-task acquisition in two nonhuman primate species. The subjects were seven rhesus monkeys (Macaca mulatta) and seven chimpanzees (Pan troglodytes). All subjects were trained to manipulate a joystick which controlled a cursor displayed on a computer monitor. Two criterion levels were used: one based on conceptual knowledge of the task and one based on motor performance. Chimpanzees and rhesus monkeys attained criterion in a comparable number of trials using a conceptually based criterion. However, using a criterion based on motor performance, chimpanzees reached criterion significantly faster than rhesus monkeys. Analysis of error patterns and latency indicated that the rhesus monkeys had a larger asymmetry in response bias and were significantly slower in responding than the chimpanzees. The results are discussed in terms of the relation between object manipulation skills and video-task acquisition.
Noah, Benjamin; Li, Jingwen; Rothrock, Ling
2017-10-01
The objectives of this study were to test the effect of interaction device on performance in a process control task (managing a tank farm). The study compared the following two conditions: a) 4K-resolution 55" screen with a 21" touchscreen versus b) 4K-resolution 55″ screen with keyboard/mouse. The touchscreen acted both as an interaction device for data entry and navigation and as an additional source of information. A within-subject experiment was conducted among 20 college engineering students. A primary task of preventing tanks from overfilling as well as a secondary task of manual logging with situation awareness questions were designed for the study. Primary Task performance (including tank level at discharge, number of tank discharged and performance score), Secondary Task Performance (including Tank log count, performance score), system interaction times, subjective workload, situation awareness questionnaire, user experience survey regarding usability and condition comparison were used as the measures. Parametric data resulted in two metrics statistically different means between the two conditions: The 4K-keyboard condition resulted in faster Detection + Navigation time compared to the 4K-touchscreen condition, by about 2 s, while participants within the 4K-touchscreen condition were about 2 s faster in data entry than in the 4K-keyboard condition. No significant results were found for: performance on the secondary task, situation awareness, and workload. Additionally, no clear significant differences were found in the non-parametric data analysis. However, participants showed a slight preference for the 4K-touchscreen condition compared to the 4K-keyboard condition in subjective responses in comparing the conditions. Introducing the touchscreen as an additional/alternative input device showed to have an effect in interaction times, which suggests that proper design considerations need to be made. While having values shown on the interaction device provides value, a potential issue of visual distraction exists when having an additional visual display. The allocation of visual attention between primary displays and the touchscreen should be further investigated. Copyright © 2017 Elsevier Ltd. All rights reserved.
Yong, Chul Soon; Choi, Young-Kwon; Kim, Yong-Il; Park, Byung-Joo; Quan, Qi-Zhe; Rhee, Jong-Dal; Kim, Chong-Kook; Choi, Han-Gon
2003-02-01
Liquid suppository systems composed of poloxamers and bioadhesive polymers were easy to administer to the anus and mucoadhesive to the rectal tissues without leakage after the dose. However, a liquid suppository containing diclofenac sodium could not be developed using bioadhesive polymers, since the drug was precipitated in this preparation. To develop a liquid suppository system using sodium chloride instead of bioadhesive polymers, the physicochemical properties such as gelation temperature, gel strength and bioadhesive force of various formulations composed of diclofenac sodium, poloxamers and sodium chloride were investigated. Furthermore, the pharmacokinetic study of diclofenac sodium delivered by the liquid suppository was performed. Diclofenac sodium significantly increased the gelation temperature and weakened the gel strength and bioadhesive force, while sodium chloride did the opposite. The liquid suppositories with less than 1.0% of sodium chloride, in which the drug was not precipitated, were inserted into the rectum without difficulty and leakage. Furthermore, liquid suppository gave significantly higher initial plasma concentrations and faster Tmax of diclofenac sodium than did solid suppository, indicating that drug from liquid suppository could be absorbed faster than that from solid one in rats. Our results suggested that a thermosensitive liquid suppository system with sodium chloride and poloxamers was a more physically stable, convenient and effective rectal dosage form for diclofenac sodium.
Looking and touching: What extant approaches reveal about the structure of early word knowledge
Hendrickson, Kristi; Mitsven, Samantha; Poulin-Dubois, Diane; Zesiger, Pascal; Friend, Margaret
2014-01-01
The goal of the current study is to assess the temporal dynamics of vision and action to evaluate the underlying word representations that guide infants’ responses. Sixteen-month-old infants participated in a two-alternative forced-choice word-picture matching task. We conducted a moment-by-moment analysis of looking and reaching behaviors as they occurred in tandem to assess the speed with which a prompted word was processed (visual reaction time) as a function of the type of haptic response: Target, Distractor, or No Touch. Visual reaction times (visual RTs) were significantly slower during No Touches compared to Distractor and Target Touches, which were statistically indistinguishable. The finding that visual RTs were significantly faster during Distractor Touches compared to No Touches suggests that incorrect and absent haptic responses appear to index distinct knowledge states: incorrect responses are associated with partial knowledge whereas absent responses appear to reflect a true failure to map lexical items to their target referents. Further, we found that those children who were faster at processing words were also those children who exhibited better haptic performance. This research provides a methodological clarification on knowledge measured by the visual and haptic modalities and new evidence for a continuum of word knowledge in the second year of life. PMID:25444711
Black, Emily; Stevenson, Jennifer L; Bish, Joel P
2017-08-01
The global precedence effect is a phenomenon in which global aspects of visual and auditory stimuli are processed before local aspects. Individuals with musical experience perform better on all aspects of auditory tasks compared with individuals with less musical experience. The hemispheric lateralization of this auditory processing is less well-defined. The present study aimed to replicate the global precedence effect with auditory stimuli and to explore the lateralization of global and local auditory processing in individuals with differing levels of musical experience. A total of 38 college students completed an auditory-directed attention task while electroencephalography was recorded. Individuals with low musical experience responded significantly faster and more accurately in global trials than in local trials regardless of condition, and significantly faster and more accurately when pitches traveled in the same direction (compatible condition) than when pitches traveled in two different directions (incompatible condition) consistent with a global precedence effect. In contrast, individuals with high musical experience showed less of a global precedence effect with regards to accuracy, but not in terms of reaction time, suggesting an increased ability to overcome global bias. Further, a difference in P300 latency between hemispheres was observed. These findings provide a preliminary neurological framework for auditory processing of individuals with differing degrees of musical experience.
Verdaasdonk, E G G; Stassen, L P S; van Wijk, R P J; Dankelman, J
2007-02-01
Psychomotor skills for endoscopic surgery can be trained with virtual reality simulators. Distributed training is more effective than massed training, but it is unclear whether distributed training over several days is more effective than distributed training within 1 day. This study aimed to determine which of these two options is the most effective for training endoscopic psychomotor skills. Students with no endoscopic experience were randomly assigned either to distributed training on 3 consecutive days (group A, n = 10) or distributed training within 1 day (group B, n = 10). For this study the SIMENDO virtual reality simulator for endoscopic skills was used. The training involved 12 repetitions of three different exercises (drop balls, needle manipulation, 30 degree endoscope) in differently distributed training schedules. All the participants performed a posttraining test (posttest) for the trained tasks 7 days after the training. The parameters measured were time, nontarget environment collisions, and instrument path length. There were no significant differences between the groups in the first training session for all the parameters. In the posttest, group A (training over several days) performed 18.7% faster than group B (training on 1 day) (p = 0.013). The collision and path length scores for group A did not differ significantly from the scores for group B. The distributed group trained over several days was faster, with the same number of errors and the same instrument path length used. Psychomotor skill training for endoscopic surgery distributed over several days is superior to training on 1 day.
The effects of load carriage on joint work at different running velocities.
Liew, Bernard X W; Morris, Susan; Netto, Kevin
2016-10-03
Running with load carriage has become increasingly prevalent in sport, as well as many field-based occupations. However, the "sources" of mechanical work during load carriage running are not yet completely understood. The purpose of this study was to determine the influence of load magnitudes on the mechanical joint work during running, across different velocities. Thirty-one participants performed overground running at three load magnitudes (0%, 10%, 20% body weight), and at three velocities (3, 4, 5m/s). Three dimensional motion capture was performed, with synchronised force plate data captured. Inverse dynamics was used to quantify joint work in the stance phase of running. Joint work was normalized to a unit proportion of body weight and leg length (one dimensionless work unit=532.45J). Load significantly increased total joint work and total positive work and this effect was greater at faster velocities. Load carriage increased ankle positive work (β coefficient=rate of 6.95×10 -4 unit work per 1% BW carried), and knee positive (β=1.12×10 -3 unit) and negative work (β=-2.47×10 -4 unit), and hip negative work (β=-7.79×10 -4 unit). Load carriage reduced hip positive work and this effect was smaller at faster velocities. Inter-joint redistribution did not contribute significantly to altered mechanical work within the spectrum of load and velocity investigated. Hence, the ankle joint contributed to the greatest extent in work production, whilst that of the knee contributed to the greatest extent to work absorption when running with load. Copyright © 2016 Elsevier Ltd. All rights reserved.
Running Performance With Nutritive and Nonnutritive Sweetened Mouth Rinses.
Hawkins, Keely R; Krishnan, Sridevi; Ringos, Lara; Garcia, Vanessa; Cooper, Jamie A
2017-09-01
Using mouth rinse (MR) with carbohydrate during exercise has been shown to act as an ergogenic aid. To investigate if nutritive or nonnutritive sweetened MR affects exercise performance and to assess the influence of sweetness intensity on endurance performance during a time trial (TT). This randomized, single-blinded study had 4 treatment conditions. Sixteen subjects (9 men, 7 women) completed a 12.8-km TT 4 different times. During each TT, subjects mouth-rinsed and expectorated a different solution at time 0 and every 12.5% of the TT. The 4 MR solutions were sucrose (S) (sweet taste and provides energy of 4 kcal/g), a lower-intensity sucralose (S1:1) (artificial sweetener that provides no energy but tastes sweet), a higher-intensity sucralose (S100:1), and water as control (C). Completion times for each TT, heart rate (HR), and ratings of perceived exertion (RPE) were also recorded. Completion time for S was faster than for C (1:03:47 ± 00:02:17 vs 1:06:56 ± 00:02:18, respectively; P < .001) and showed a trend to be faster vs S100:1 (1:03:47 ± 00:02:17 vs 1:05:38 ± 00:02:12, respectively; P = .07). No other TT differences were found. Average HR showed a trend to be higher for S vs C (P = .08). The only difference in average or maximum RPE was for higher maximum RPE in C vs S1:1 (P = .02). A sweet-tasting MR did improve endurance performance compared with water in a significant manner (mean 4.5% improvement; 3+ min.); however, the presence of energy in the sweet MR appeared necessary since the artificial sweeteners did not improve performance more than water alone.
Running Performance with Nutritive and Non-Nutritive Sweetened Mouth Rinses
Hawkins, Keely H.; Krishnan, Sridevi; Ringos, Lara; Garcia, Vanessa; Cooper, Jamie A.
2017-01-01
Mouth rinsing (MR) with carbohydrate during exercise has been shown to act as an ergogenic aid. Purpose To investigate if nutritive or nonnutritive sweetened MR affect exercise performance, and to assess the influence of sweetness intensity on endurance performance during a time-trial (TT). Methods This randomized, single blinded study had 4 treatment conditions. 16 subjects (9 men, 7 women) completed a 12.8km TT four different times. During each TT, subjects MR and expectorated a different solution at time 0 and every 12.5% of the TT. The 4 MR solutions were: sucrose (S) (sweet taste and provides energy of 4 kcals/g), a lower intensity sucralose (S1:1) (artificial sweetener that provides no energy but tastes sweet), a higher intensity sucralose (S100:1), and water as control (C). Completion times for each TT, heart rate (HR) and ratings of perceived exertion (RPE) were also recorded. Results Completion time for S was faster than C (1:03:47±00:02:17 vs. 1:06:56±00:02:18; p<0.001, respectively), and showed a trend to be faster vs. S100:1 (1:03:47±00:02:17 vs. 1:05:38±00:02:12; p=0.07, respectively). No other TT differences were found. Average HR showed a trend to be higher for S vs. C (p=0.08). There only differences in average or max RPE was for higher max RPE in C vs. S1:1 (p=0.02). Conclusion A sweet tasting MR did improve endurance performance compared to water in a significant manner (avg. 4.5% improvement; 3+ min.); however, the presence of energy in the sweet MR appeared necessary since the artificial sweeteners did not improve performance more than water alone. PMID:28095077
Computing Maximum Cardinality Matchings in Parallel on Bipartite Graphs via Tree-Grafting
DOE Office of Scientific and Technical Information (OSTI.GOV)
Azad, Ariful; Buluc, Aydn; Pothen, Alex
It is difficult to obtain high performance when computing matchings on parallel processors because matching algorithms explicitly or implicitly search for paths in the graph, and when these paths become long, there is little concurrency. In spite of this limitation, we present a new algorithm and its shared-memory parallelization that achieves good performance and scalability in computing maximum cardinality matchings in bipartite graphs. This algorithm searches for augmenting paths via specialized breadth-first searches (BFS) from multiple source vertices, hence creating more parallelism than single source algorithms. Algorithms that employ multiple-source searches cannot discard a search tree once no augmenting pathmore » is discovered from the tree, unlike algorithms that rely on single-source searches. We describe a novel tree-grafting method that eliminates most of the redundant edge traversals resulting from this property of multiple-source searches. We also employ the recent direction-optimizing BFS algorithm as a subroutine to discover augmenting paths faster. Our algorithm compares favorably with the current best algorithms in terms of the number of edges traversed, the average augmenting path length, and the number of iterations. Here, we provide a proof of correctness for our algorithm. Our NUMA-aware implementation is scalable to 80 threads of an Intel multiprocessor and to 240 threads on an Intel Knights Corner coprocessor. On average, our parallel algorithm runs an order of magnitude faster than the fastest algorithms available. The performance improvement is more significant on graphs with small matching number.« less
Computing Maximum Cardinality Matchings in Parallel on Bipartite Graphs via Tree-Grafting
Azad, Ariful; Buluc, Aydn; Pothen, Alex
2016-03-24
It is difficult to obtain high performance when computing matchings on parallel processors because matching algorithms explicitly or implicitly search for paths in the graph, and when these paths become long, there is little concurrency. In spite of this limitation, we present a new algorithm and its shared-memory parallelization that achieves good performance and scalability in computing maximum cardinality matchings in bipartite graphs. This algorithm searches for augmenting paths via specialized breadth-first searches (BFS) from multiple source vertices, hence creating more parallelism than single source algorithms. Algorithms that employ multiple-source searches cannot discard a search tree once no augmenting pathmore » is discovered from the tree, unlike algorithms that rely on single-source searches. We describe a novel tree-grafting method that eliminates most of the redundant edge traversals resulting from this property of multiple-source searches. We also employ the recent direction-optimizing BFS algorithm as a subroutine to discover augmenting paths faster. Our algorithm compares favorably with the current best algorithms in terms of the number of edges traversed, the average augmenting path length, and the number of iterations. Here, we provide a proof of correctness for our algorithm. Our NUMA-aware implementation is scalable to 80 threads of an Intel multiprocessor and to 240 threads on an Intel Knights Corner coprocessor. On average, our parallel algorithm runs an order of magnitude faster than the fastest algorithms available. The performance improvement is more significant on graphs with small matching number.« less
Effects of radiotransmitters on the reproductive performance of Cassin's auklets
Ackerman, Joshua T.; Adams, Josh; Takekawa, John Y.; Carter, Harry R.; Whitworth, Darrell L.; Newman, Scott H.; Golightly, Richard T.; Orthmeyer, Dennis L.
2004-01-01
We examined whether radiotransmitters adversely affected the reproductive performance of Cassin's auklets (Ptychoramphus aleuticus) breeding on the California Channel Islands during 1999-2001. We attached external radiotransmitters to 1 partner in 108 Cassin's auklet pairs after nest initiation and used 131 unmarked, but handled, pairs as controls. Compared to alpha chicks raised by radiomarked pairs, alpha chicks raised by unmarked pairs had faster mass growth rates (1.95 ± 0.30 g d−1 vs. 3.37 ± 0.53 g d−1, respectively), faster wing growth rates (2.46 ± 0.10 mm d−1 vs. 2.85 ± 0.05 mm d−1), greater peak fledging masses (118.9 ± 3.5 g vs. 148.3 ± 2.4 g), and higher fledging success (61% vs. 90%). Fledging success was reduced more when we radiomarked the male (50% fledged) rather than the female partner (77% fledged). After fledging an alpha chick, unmarked pairs were more likely to initiate a second clutch (radiomarked: 7%; unmarked: 39%) but did not hatch a second egg (radiomarked: 4%; unmarked: 25%) or fledge a second (beta) chick (radiomarked: 4%; unmarked: 18%) significantly more often than radiomarked pairs. We resighted 12 radiomarked individuals nesting during a subsequent breeding season; each bird had shed its transmitter and healed the site of attachment. We suggest caution in using telemetry to evaluate the reproductive performance of alcids, but marking only females may minimize adverse effects.
Systematic evaluation of deep learning based detection frameworks for aerial imagery
NASA Astrophysics Data System (ADS)
Sommer, Lars; Steinmann, Lucas; Schumann, Arne; Beyerer, Jürgen
2018-04-01
Object detection in aerial imagery is crucial for many applications in the civil and military domain. In recent years, deep learning based object detection frameworks significantly outperformed conventional approaches based on hand-crafted features on several datasets. However, these detection frameworks are generally designed and optimized for common benchmark datasets, which considerably differ from aerial imagery especially in object sizes. As already demonstrated for Faster R-CNN, several adaptations are necessary to account for these differences. In this work, we adapt several state-of-the-art detection frameworks including Faster R-CNN, R-FCN, and Single Shot MultiBox Detector (SSD) to aerial imagery. We discuss adaptations that mainly improve the detection accuracy of all frameworks in detail. As the output of deeper convolutional layers comprise more semantic information, these layers are generally used in detection frameworks as feature map to locate and classify objects. However, the resolution of these feature maps is insufficient for handling small object instances, which results in an inaccurate localization or incorrect classification of small objects. Furthermore, state-of-the-art detection frameworks perform bounding box regression to predict the exact object location. Therefore, so called anchor or default boxes are used as reference. We demonstrate how an appropriate choice of anchor box sizes can considerably improve detection performance. Furthermore, we evaluate the impact of the performed adaptations on two publicly available datasets to account for various ground sampling distances or differing backgrounds. The presented adaptations can be used as guideline for further datasets or detection frameworks.
Phonological priming in young children who stutter: holistic versus incremental processing.
Byrd, Courtney T; Conture, Edward G; Ohde, Ralph N
2007-02-01
To investigate the holistic versus incremental phonological encoding processes of young children who stutter (CWS; N = 26) and age- and gender-matched children who do not stutter (CWNS; N = 26) via a picture-naming auditory priming paradigm. Children named pictures during 3 auditory priming conditions: neutral, holistic, and incremental. Speech reaction time (SRT) was measured from the onset of picture presentation to the onset of participant response. CWNS shifted from being significantly faster in the holistic priming condition to being significantly faster in the incremental priming condition from 3 to 5 years of age. In contrast, the majority of 3- and 5-year-old CWS continued to exhibit faster SRT in the holistic than the incremental condition. CWS are delayed in making the developmental shift in phonological encoding from holistic to incremental processing, a delay that may contribute to their difficulties establishing fluent speech.
Zone-dependent changes in human vertebral trabecular bone: clinical implications.
Thomsen, Jesper Skovhus; Ebbesen, E N; Mosekilde, Li
2002-05-01
We have previously shown that there are pronounced age-related changes in human vertebral cancellous bone density and microarchitecture. However, the magnitude of these changes seemed to be dependent on zone location in the vertebral body-the central third vs. the areas adjacent to the endplates. The aim of the present study was, therefore, to investigate whether such zone-specific differences could be identified by static histomorphometric measures. The material comprised 48 individuals (24 women aged 19-97 years, and 24 men aged 23-95 years). Three of the women had a known fracture of the L-2. From each L-2, thick frontal sections of half of the vertebra were embedded undecalcified in methylmethacrylate, cut into 10-microm-thick sections, and stained with aniline blue. The sections were scanned into a computer, and classic static histomorphometry was performed on the images. The histomorphometry was performed on both the whole section and on the separate zones (central and sub-endplate zone). The results showed that trabecular bone volume, trabecular number, and connectivity density decreased significantly faster with age, whereas marrow space star volume increased significantly faster with age in the zones adjacent to the endplates than in the central zone. The other histomorphometric measures showed no zone specificity in relation to aging. However, trabecular thickness and trabecular separation were both higher at all ages in the central zone than in the sub-endplate zone, although this was significant only for trabecular separation. The described differences might have significant clinical implications concerning quantitative computed tomography (QCT) scanning, X-ray analyses, and assessment of fracture liability in the human spine, but the underlying pathogenesis is still not known. This study shows that the human vertebral body can be described as two distinct zones with very specific age-related changes in density and microstructure. This zone-specificity is important for the correct interpretation of clinical data.
Li, Bin; Gu, Meng; Nie, Zimin; Shao, Yuyan; Luo, Qingtao; Wei, Xiaoliang; Li, Xiaolin; Xiao, Jie; Wang, Chongmin; Sprenkle, Vincent; Wang, Wei
2013-03-13
Employing electrolytes containing Bi(3+), bismuth nanoparticles are synchronously electrodeposited onto the surface of a graphite felt electrode during operation of an all-vanadium redox flow battery (VRFB). The influence of the Bi nanoparticles on the electrochemical performance of the VRFB is thoroughly investigated. It is confirmed that Bi is only present at the negative electrode and facilitates the redox reaction between V(II) and V(III). However, the Bi nanoparticles significantly improve the electrochemical performance of VRFB cells by enhancing the kinetics of the sluggish V(II)/V(III) redox reaction, especially under high power operation. The energy efficiency is increased by 11% at high current density (150 mA·cm(-2)) owing to faster charge transfer as compared with one without Bi. The results suggest that using Bi nanoparticles in place of noble metals offers great promise as high-performance electrodes for VRFB application.
Detection of system failures in multi-axes tasks. [pilot monitored instrument approach
NASA Technical Reports Server (NTRS)
Ephrath, A. R.
1975-01-01
The effects of the pilot's participation mode in the control task on his workload level and failure detection performance were examined considering a low visibility landing approach. It is found that the participation mode had a strong effect on the pilot's workload, the induced workload being lowest when the pilot acted as a monitoring element during a coupled approach and highest when the pilot was an active element in the control loop. The effects of workload and participation mode on failure detection were separated. The participation mode was shown to have a dominant effect on the failure detection performance, with a failure in a monitored (coupled) axis being detected significantly faster than a comparable failure in a manually controlled axis.
Coverage-maximization in networks under resource constraints.
Nandi, Subrata; Brusch, Lutz; Deutsch, Andreas; Ganguly, Niloy
2010-06-01
Efficient coverage algorithms are essential for information search or dispersal in all kinds of networks. We define an extended coverage problem which accounts for constrained resources of consumed bandwidth B and time T . Our solution to the network challenge is here studied for regular grids only. Using methods from statistical mechanics, we develop a coverage algorithm with proliferating message packets and temporally modulated proliferation rate. The algorithm performs as efficiently as a single random walker but O(B(d-2)/d) times faster, resulting in significant service speed-up on a regular grid of dimension d . The algorithm is numerically compared to a class of generalized proliferating random walk strategies and on regular grids shown to perform best in terms of the product metric of speed and efficiency.
Caputo, M P; Benson, E R; Pritchett, E M; Hougentogler, D P; Jain, P; Patil, C; Johnson, A L; Alphin, R L
2012-12-01
The mass depopulation of production birds remains an effective means of controlling fast-moving, highly infectious diseases such as avian influenza and virulent Newcastle disease. Two experiments were performed to compare the physiological responses of White Pekin commercial ducks during foam depopulation and CO(2) gas depopulation. Both experiment 1 (5 to 9 wk of age) and 2 (8 to 14 wk of age) used electroencephalogram, electrocardiogram, and accelerometer to monitor and evaluate the difference in time to unconsciousness, motion cessation, brain death, altered terminal cardiac activity, duration of bradycardia, and elapsed time from onset of bradycardia to onset of unconsciousness between foam and CO(2) gas. Experiment 2 also added a third treatment, foam + atropine injection, to evaluate the effect of suppressing bradycardia. Experiment 1 resulted in significantly shorter times for all 6 physiological points for CO(2) gas compared with foam, whereas experiment 2 found that there were no significant differences between foam and CO(2) gas for these physiological points except brain death, in which CO(2) was significantly faster than foam and duration of bradycardia, which was shorter for CO(2). Experiment 2 also determined there was a significant positive correlation between duration of bradycardia and time to unconsciousness, motion cessation, brain death, and altered terminal cardiac activity. The time to unconsciousness, motion cessation, brain death, and altered terminal cardiac activity was significantly faster for the treatment foam + atropine injection compared with foam. Both experiments showed that bradycardia can occur as a result of either submersion in foam or exposure to CO(2) gas. The duration of bradycardia has a significant impact on the time it takes White Pekin ducks to reach unconsciousness and death during depopulation.
Tavakoli, J; Costi, J J
2018-04-15
While few studies have improved our understanding of composition and organization of elastic fibres in the inter-lamellar matrix (ILM), its clinical relevance is not fully understood. Moreover, no studies have measured the direct tensile and shear failure and viscoelastic properties of the ILM. Therefore, the aim of this study was, for the first time, to measure the viscoelastic and failure properties of the ILM in both the tension and shear directions of loading. Using an ovine model, isolated ILM samples were stretched to 40% of their initial length at three strain rates of 0.1%s -1 (slow), 1%s -1 (medium) and 10%s -1 (fast) and a ramp test to failure was performed at a strain rate of 10%s -1 . The findings from this study identified that the stiffness of the ILM was significantly larger at faster strain rates, and energy absorption significantly smaller, compared to slower strain rates, and the viscoelastic and failure properties were not significantly different under tension and shear loading. We found a strain rate dependent response of the ILM during dynamic loading, particularly at the fastest rate. The ILM demonstrated a significantly higher capability for energy absorption at slow strain rates compared to medium and fast strain rates. A significant increase in modulus was found in both loading directions and all strain rates, having a trend of larger modulus in tension and at faster strain rates. The finding of no significant difference in failure properties in both loading directions, was consistent with our previous ultra-structural studies that revealed a well-organized (±45°) elastic fibre orientation in the ILM. The results from this study can be used to develop and validate finite element models of the AF at the tissue scale, as well as providing new strategies for fabricating tissue engineered scaffolds. While few studies have improved our understanding of composition and organization of elastic fibres in the inter-lamellar matrix (ILM) of the annulus in the disc no studies have measured the direct mechanical failure and viscoelastic properties of the ILM. The findings from this study identified that the stiffness of the ILM was significantly larger at faster strain rates, and energy absorption significantly smaller, compared to slower strain rates. The failure properties of the ILM were not significantly different under tension and shear. Copyright © 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Thirthalli, Jagadisha; Phutane, Vivek H; Muralidharan, Kesavan; Kumar, Channaveerachari Naveen; Munishwar, Bharat; Baspure, Prashant; Gangadhar, Bangalore N
2009-01-01
Electroconvulsive therapy (ECT) is generally recommended for treating catatonic schizophrenia. Non-catatonic schizophrenia patients also receive ECT. We compared the speed of response to ECT among patients with catatonic and other subtypes of schizophrenia. Consecutive schizophrenia patients referred for ECT within 3 months of starting antipsychotic treatment were studied (19 with catatonic and 34 with non-catatonic schizophrenia). Nurse's Observation Scale for Inpatient Evaluation (NOSIE-30) and Clinical Global Impression (CGI) were used to rate improvement. Referring psychiatrists stopped ECTs based on clinical impression of improvement. Total number of ECTs was taken as an indirect measure of speed of response. NOSIE-30 scores were compared using repeated measures analysis of variance. Catatonic schizophrenia patients required significantly fewer ECTs to achieve clinically significant improvement. There was a significant group x occasion effect in NOSIE scores, suggesting faster response to ECT in the catatonia group (F=41.6; P<0.001). Survival analysis suggested that patients with catatonic schizophrenia required significantly fewer ECTs (one less session on an average) to achieve clinical improvement (Log-rank statistic =5.31; P=0.02). Catatonic schizophrenia responds faster to ECT than non-catatonic schizophrenia. However, the magnitude of the difference is modest.
Seebacher, F; Franklin, C E
2001-12-01
During thermoregulation in the bearded dragon Pogona barbata, heart rate when heating is significantly faster than when cooling at any given body temperature (heart rate hysteresis), resulting in faster rates of heating than cooling. However, the mechanisms that control heart rate during heating and cooling are unknown. The aim of this study was to test the hypothesis that changes in cholinergic and adrenergic tone on the heart are responsible for the heart rate hysteresis during heating and cooling in P. barbata. Heating and cooling trials were conducted before and after the administration of atropine, a muscarinic antagonist, and sotalol, a beta-adrenergic antagonist. Cholinergic and beta-adrenergic blockade did not abolish the heart rate hysteresis, as the heart rate during heating was significantly faster than during cooling in all cases. Adrenergic tone was extremely high (92.3 %) at the commencement of heating, and decreased to 30.7 % at the end of the cooling period. Moreover, in four lizards there was an instantaneous drop in heart rate (up to 15 beats min(-1)) as the heat source was switched off, and this drop in heart rate coincided with either a drop in beta-adrenergic tone or an increase in cholinergic tone. Rates of heating were significantly faster during the cholinergic blockade, and least with a combined cholinergic and beta-adrenergic blockade. The results showed that cholinergic and beta-adrenergic systems are not the only control mechanisms acting on the heart during heating and cooling, but they do have a significant effect on heart rate and on rates of heating and cooling.
Sleep Management Strategy and Performance in an Extreme Mountain Ultra-marathon.
Poussel, Mathias; Laroppe, Julien; Hurdiel, Rémy; Girard, Julien; Poletti, Laurence; Thil, Catherine; Didelot, Antoine; Chenuel, Bruno
2015-01-01
We intended to assess the relationship between sleep strategies and performance during the North-Face Ultra-Trail du Mont-Blanc 2013, to test the hypothesis that sleep management can influence athletic performance. Almost all runners specifically adopted sleep management strategies before the race. Among the finishers 72% didn't sleep at all during the race and 28% took a least one break for sleep. Non-sleepers completed the race faster than the sleepers (P = 0.0008). Race time was positively correlated with drowsiness (P < 0.0001) and negatively correlated with the number participations in this race (P = 0.0039). Runners who adopted a sleep management strategy based on increased sleep time before the race completed the race faster (P = 0.0258). Most finishers seemed to be aware of the importance of developing sleep management strategies and increasing sleep time some nights before the race appeared to be the most relevant strategy to improve performance.
Faber, Anne; Strøyer, Jesper; Hjortskov, Nis; Schibye, Bente
2010-01-01
To investigate changes of physical performance during long working hours and extended workweeks among construction workers with temporary accommodation in camps. Nineteen construction workers with 12-h workdays and extended workweeks participated. Physical performance in the morning and evening of the second and eleventh workdays was tested by endurance, ability to react to a sudden load, flexibility of the back, handgrip strength and sub-maximal HR during a bicycle test. HR was registered throughout two separate workdays. HR during each of the two separate workdays corresponded to a relative workload of 25%. Sub-maximal HR was lower, reaction time faster and handgrip strength higher in the end of each test day. In the end of the work period, sub-maximal HR was lower, reaction time faster and sitting balance was better. No trends of decreased physical performance were found after a workday or a work period.
Vinciguerra, G; Belcaro, G; Bonanni, E; Cesarone, M R; Rotondi, V; Ledda, A; Hosoi, M; Dugall, M; Cacchio, M; Cornelli, U
2013-12-01
The aim of this registry study was to evaluate the effects of Pycnogenol® (French pine bark extract) on improving physical fitness (PF) in normal individuals using the Army Physical Fitness Test (APFT). The study evaluated the efficacy of Pycnogenol, used as a supplement, in improving training, exercise, recovery and oxidative stress. The study was divided into 2 parts. In PART 1 (Pycnogenol 100 mg/day), the APFT was used to assess an improvement in PF during an 8-week preparation and training program. In PART 2 (Pycnogenol 150 mg/day), the study evaluated the effects of Pycnogenol supplementation in athletes in training for a triathlon. PART 1. There was a significant improvement in both males and females in the 2-mile running time within both groups, but the group using Pycnogenol (74 subjects) performed statistically better than controls (73 subjects). The number of push-ups was improved, with Pycnogenol subjects performing better. Sit-ups also improved in the Pycnogenol group. Oxidative stress decreased with exercise in all subjects; in Pycnogenol subjects the results were significantly better. PART 2. In the Pycnogenol group 32 males (37.9; SD 4.4 years) were compliant with the training plan at 4 weeks. In controls there were 22 subjects (37.2;3.5) completing the training plans. The swimming, biking and running scores in both groups improved with training. The Pycnogenol group had more benefits in comparison with controls. The total triathlon time was 89 min 44 s in Pycnogenol subjects versus 96 min 5 s in controls. Controls improved their performing time on average 4.6 minutes in comparison with an improvement of 10.8 minutes in Pycnogenol subjects. A significant decrease in cramps and running and post-running pain was seen in the Pycnogenol group; there were no significant differences in controls. There was an important, significant post-triathlon decrease of PFR one hour after the end of the triathlon with an average of -26.7, whereas PFR in controls increased. In Pycnogenol subjects there was a lower increase on oxidative stress with a faster recovery to almost normal levels (<330 for these subjects). These variations in PFR values were interpreted as a faster metabolic recovery in subjects using Pycnogenol. This study opens an interesting new application of the natural supplementation with Pycnogenol that, with proper hydration, good training and nutritional attention may improve training and performances both in normal subjects and in semi-professional athletes performing at high levels in difficult, high-stress sports such as the triathlon.
Miller, Jacob A; Scult, Matthew A; Conley, Emily Drabant; Chen, Qiang; Weinberger, Daniel R; Hariri, Ahmad R
2018-06-06
Recent work has begun to shed light on the neural correlates and possible mechanisms of polygenic risk for schizophrenia. Here, we map a schizophrenia polygenic risk profile score (PRS) based on genome-wide association study significant loci onto variability in the activity and functional connectivity of a frontoparietal network supporting the manipulation versus maintenance of information during a numerical working memory (WM) task in healthy young adults (n = 99, mean age = 19.8). Our analyses revealed that higher PRS was associated with hypoactivity of the dorsolateral prefrontal cortex (dlPFC) during the manipulation but not maintenance of information in WM (r2 = .0576, P = .018). Post hoc analyses revealed that PRS-modulated dlPFC hypoactivity correlated with faster reaction times during WM manipulation (r2 = .0967, P = .002), and faster processing speed (r2 = .0967, P = .003) on a separate behavioral task. These PRS-associated patterns recapitulate dlPFC hypoactivity observed in patients with schizophrenia during central executive manipulation of information in WM on this task.
The age-related performance decline in ultraendurance mountain biking.
Haupt, Samuel; Knechtle, Beat; Knechtle, Patrizia; Rüst, Christoph Alexander; Rosemann, Thomas; Lepers, Romuald
2013-01-01
The age-related changes in ultraendurance performance have been previously examined for running and triathlon but not mountain biking. The aims of this study were (i) to describe the performance trends and (ii) to analyze the age-related performance decline in ultraendurance mountain biking in a 120-km ultraendurance mountain bike race the "Swiss Bike Masters" from 1995 to 2009 in 9,325 male athletes. The mean (±SD) race time decreased from 590 ± 80 min to 529 ± 88 min for overall finishers and from 415 ± 8 min to 359 ± 16 min for the top 10 finishers, respectively. The mean (±SD) age of all finishers significantly (P < 0.001) increased from 31.6 ± 6.5 years to 37.9 ± 8.9 years, while the age of the top 10 remained stable at 30.0 ± 1.6 years. The race time of mountain bikers aged between 25 and 34 years was significantly (P < 0.01) faster compared with the race time of older age groups. The age-related decline in performance in endurance mountain bikers in the "Swiss Bike Masters" appears to start earlier compared with other ultraendurance sports.
Hemispheric asymmetry and theory of mind: is there an association?
Herzig, Daniela A; Sullivan, Sarah; Evans, Jonathan; Corcoran, Rhiannon; Mohr, Christine
2012-01-01
In autism and schizophrenia attenuated/atypical functional hemispheric asymmetry and theory of mind impairments have been reported, suggesting common underlying neuroscientific correlates. We here investigated whether impaired theory of mind performance is associated with attenuated/atypical hemispheric asymmetry. An association may explain the co-occurrence of both dysfunctions in psychiatric populations. Healthy participants (n=129) performed a left hemisphere (lateralised lexical decision task) and right hemisphere (lateralised face decision task) dominant task as well as a visual cartoon task to assess theory of mind performance. Linear regression analyses revealed inconsistent associations between theory of mind performance and functional hemisphere asymmetry: enhanced theory of mind performance was only associated with (1) faster right hemisphere language processing, and (2) reduced right hemisphere dominance for face processing (men only). The majority of non-significant findings suggest that theory of mind and functional hemispheric asymmetry are unrelated. Instead of "overinterpreting" the two significant results, discrepancies in the previous literature relating to the problem of the theory of mind concept, the variety of tasks, and the lack of normative data are discussed. We also suggest how future studies could explore a possible link between hemispheric asymmetry and theory of mind.
Locomotor performance in highly-trained young soccer players: does body size always matter?
Buchheit, M; Mendez-Villanueva, A; Mayer, N; Jullien, H; Marles, A; Bosquet, L; Maille, P; Morin, J-B; Cazorla, G; Lambert, P
2014-06-01
To examine the effects of body size on locomotor performance, 807 15-year-old French and 64 Qatari soccer players participated in the present study. They performed a 40-m sprint and an incremental running test to assess maximal sprinting (MSS) and aerobic speeds, respectively. French players were advanced in maturity, taller, heavier, faster and fitter than their Qatari counterparts (e.g., Cohen's d=+1.3 and + 0.5 for body mass and MSS). However, when adjusted for body mass (BM), Qatari players had possibly greater MSS than French players (d=+0.2). A relative age effect was observed within both countries, with the players born in the first quarter of the year being taller, heavier and faster that those born during the fourth quarter (e.g., d=+0.2 for MSS in French players). When directly adjusted for BM, these MSS differences remained (d=+0.2). Finally, in both countries, players selected in National teams were taller, heavier, faster and fitter than their non-selected counterparts (e.g., d=+0.6 for MSS in French players), even after adjustments for body size (d=+0.5). Differences in locomotor performances between players with different phenotypes are likely mediated by differences in body size. However, when considering more homogeneous player groups, body dimensions are unlikely to substantially explain the superior locomotor performances of older and/or international players. © Georg Thieme Verlag KG Stuttgart · New York.
Halperin, Israel; Chapman, Dale W; Martin, David T; Abbiss, Chris
2017-03-01
Research indicates that instructing athlete's to focus on bodily movements (internal focus of attention [IFA]) may hinder performance, whereas instructing them to focus on the movement outcome (external focus of attention [EFA]) often enhances performance. Despite the importance of instructions in striking combat sports, limited research has examined the influence of IFA and EFA on performance in well-trained combat athletes. This study investigated the effects of different instructional cues on punching velocity (m · s -1 ) and normalised impact forces (N · kg -1 ) among intermediate (n = 8) and expert (n = 7) competitive boxers and kickboxers. Athletes completed three rounds of 12 maximal effort punches delivered to a punching integrator on three separate days. Day one was a familiarisation session with only control instructions provided. In the following two days athletes randomly received IFA, EFA or control instructions prior to each of the three rounds. Athletes punching with EFA were 4% faster and 5% more forceful than IFA (P < 0.05), and 2% faster and 3% more forceful than control (P < 0.05). Furthermore, experts punched 11% faster and with 13% greater force compared with intermediate athletes (P < 0.05). EFA led to a positive effect on punching performance and should be favoured over IFA and control instructions.
Mohammadi, Roghayeh; Ershad, Navid; Rezayinejad, Marziyeh; Fatemi, Elham; Phadke, Chetan P
2017-09-01
To examine the functional effects of walking retraining at faster than self-selected speed (SSS). Ten individuals with chronic stroke participated in a 4-week training over a treadmill at walking speeds 40% faster than SSS, three times per week, 30 min/session. Outcome measures assessed before, after, and 2 months after the end of intervention were the Timed Up and Go, the 6-Minute Walk, the 10-Meter Walk test, the Modified Ashworth Scale, SSS, and fastest comfortable speed. After 4 weeks of training, all outcome measures showed clinically meaningful and statistically significant improvements (P<0.05) that were maintained at 2 months after the end of the training. The results showed that a strategy of training at a speed 40% faster than SSS can improve functional activity in individuals with chronic stroke, with effects lasting up to 2 months after the intervention.
Erwin; Gunanti; Handharyani, Ekowati; Noviana, Deni
2016-05-01
The success of a skin graft in a cat is highly dependent on the granulation formed by the base of recipient bed. Granulation by the base of recipient bed will form after several days after injury. This research aimed to observe subjective and objective profile of skin graft recovery on forelimb of cats with different periods of donor skin placement. Nine male Indonesian local cats aged 1-2 years old, weighing 3-4 kg were divided into three groups. The first surgery for creating defect wound of 2 cm×2 cm in size was performed in the whole group. The wound was left for several days with the respective interval for each group, respectively: Group I (for 2 days), Group II (for 4 days), and Group III (for 6 days). In the whole group, the second surgery was done by the harvesting skin of thoracic area which then applied on recipient bed of respective groups. The donor skin on Group II was accepted faster compared to Group I and Group III. The donor skin did not show color differences compared to surrounding skin, painless, bright red in bleeding test had faster both hair growth and drug absorption. Test toward the size of donor skin and the effect of drugs did not show a significant difference between each group. The observe subjective and objective profile of skin graft recovery on forelimb of cats on Group II were accepted faster compared to Group I and III.
Modifications of the PCPT method for HJB equations
NASA Astrophysics Data System (ADS)
Kossaczký, I.; Ehrhardt, M.; Günther, M.
2016-10-01
In this paper we will revisit the modification of the piecewise constant policy timestepping (PCPT) method for solving Hamilton-Jacobi-Bellman (HJB) equations. This modification is called piecewise predicted policy timestepping (PPPT) method and if properly used, it may be significantly faster. We will quickly recapitulate the algorithms of PCPT, PPPT methods and of the classical implicit method and apply them on a passport option pricing problem with non-standard payoff. We will present modifications needed to solve this problem effectively with the PPPT method and compare the performance with the PCPT method and the classical implicit method.
High Efficiency Photonic Switch for Data Centers
DOE Office of Scientific and Technical Information (OSTI.GOV)
LaComb, Lloyd J.; Bablumyan, Arkady; Ordyan, Armen
2016-12-06
The worldwide demand for instant access to information is driving internet growth rates above 50% annually. This rapid growth is straining the resources and architectures of existing data centers, metro networks and high performance computer centers. If the current business as usual model continues, data centers alone will require 400TWhr of electricity by 2020. In order to meet the challenges of a faster and more cost effective data centers, metro networks and supercomputing facilities, we have demonstrated a new type of optical switch that will support transmissions speeds up to 1Tb/s, and requires significantly less energy per bit than
Parasail: SIMD C library for global, semi-global, and local pairwise sequence alignments.
Daily, Jeff
2016-02-10
Sequence alignment algorithms are a key component of many bioinformatics applications. Though various fast Smith-Waterman local sequence alignment implementations have been developed for x86 CPUs, most are embedded into larger database search tools. In addition, fast implementations of Needleman-Wunsch global sequence alignment and its semi-global variants are not as widespread. This article presents the first software library for local, global, and semi-global pairwise intra-sequence alignments and improves the performance of previous intra-sequence implementations. A faster intra-sequence local pairwise alignment implementation is described and benchmarked, including new global and semi-global variants. Using a 375 residue query sequence a speed of 136 billion cell updates per second (GCUPS) was achieved on a dual Intel Xeon E5-2670 24-core processor system, the highest reported for an implementation based on Farrar's 'striped' approach. Rognes's SWIPE optimal database search application is still generally the fastest available at 1.2 to at best 2.4 times faster than Parasail for sequences shorter than 500 amino acids. However, Parasail was faster for longer sequences. For global alignments, Parasail's prefix scan implementation is generally the fastest, faster even than Farrar's 'striped' approach, however the opal library is faster for single-threaded applications. The software library is designed for 64 bit Linux, OS X, or Windows on processors with SSE2, SSE41, or AVX2. Source code is available from https://github.com/jeffdaily/parasail under the Battelle BSD-style license. Applications that require optimal alignment scores could benefit from the improved performance. For the first time, SIMD global, semi-global, and local alignments are available in a stand-alone C library.
Rapid Classification of Ordinary Chondrites Using Raman Spectroscopy
NASA Technical Reports Server (NTRS)
Fries, M.; Welzenbach, L.
2014-01-01
Classification of ordinary chondrites is typically done through measurements of the composition of olivine and pyroxenes. Historically, this measurement has usually been performed via electron microprobe, oil immersion or other methods which can be costly through lost sample material during thin section preparation. Raman microscopy can perform the same measurements but considerably faster and with much less sample preparation allowing for faster classification. Raman spectroscopy can facilitate more rapid classification of large amounts of chondrites such as those retrieved from North Africa and potentially Antarctica, are present in large collections, or are submitted to a curation facility by the public. With development, this approach may provide a completely automated classification method of all chondrite types.
Trapani, Stefano; Navaza, Jorge
2006-07-01
The FFT calculation of spherical harmonics, Wigner D matrices and rotation function has been extended to all angular variables in the AMoRe molecular replacement software. The resulting code avoids singularity issues arising from recursive formulas, performs faster and produces results with at least the same accuracy as the original code. The new code aims at permitting accurate and more rapid computations at high angular resolution of the rotation function of large particles. Test calculations on the icosahedral IBDV VP2 subviral particle showed that the new code performs on the average 1.5 times faster than the original code.
The utility of a "trauma 1 OP" activation at a level 1 pediatric trauma center.
Hunt, Madison M; Stevens, Austin M; Hansen, Kristine W; Fenton, Stephen J
2017-02-01
To expedite flow of injured children suspected to require operative intervention, a "trauma 1 OP" (T1OP) activation classification was created. The purpose of this study was to review this strategy at a level 1 pediatric trauma center. A retrospective review of T1OP activations between 2003 and 2015 was performed. Children suspected of requiring neurosurgical intervention were classified as trauma 1 OP neuro (T1OP(N)). Comparisons were made to trauma 1 (T1) patients who required emergent operative intervention, excluding orthopedic injuries. Overall, 461 T1OP activations occurred (72% T1OP(N)) compared to 129 T1 activations requiring emergent surgery. Demographics were not significantly different between groups, although T1OP patients were slightly younger and more often experienced falls or were victims of abuse. Compared to T1 activations, T1OP activations had a significantly higher mortality rate (21% vs. 7%, p<0.001). Repeat head imaging was more common in the T1OP(N) group compared to imaged children in the T1 group (20% vs. 37%, p=0.05). T1OP(N) patients more often went directly to the OR (45% vs. 33%, p=0.02) and did so in a significantly faster period of time (32min vs. 53min, p<0.001). Use of the T1OP activations appropriately triaged surgical patients, resulting in significantly faster transport times to the OR. II, prognosis study. Copyright © 2017 Elsevier Inc. All rights reserved.
Motion analysis of throwing Boccia balls in children with cerebral palsy.
Huang, Po-Chang; Pan, Po-Jung; Ou, Yu-Chih; Yu, Yi-Chen; Tsai, Yung-Shen
2014-02-01
Boccia is a sport suitable for children with cerebral palsy (CP). Throwing Boccia balls requires upper extremity and torso coordination. This study investigated the differences between children with CP and normally developed children regarding throwing patterns of Boccia balls. Thirteen children with bilateral spastic CP and 20 normally developed children participated in this study. The tests in this study were a pediatric reach test and throwing of Boccia balls. A 3D electromagnetic motion tracking system and a force plate were synchronized to record and analyze biomechanical parameters of throwing Boccia balls. The results of the pediatric reach test for participants with CP were significantly worse than those for normally developed participants. The 2 groups of participants did not significantly differ regarding the distance between a thrown Boccia ball and a target ball (jack). Participants with CP demonstrated significantly longer movement duration, smaller amplitude of elbow movement, greater amplitudes of shoulder abduction and flexion, slower maximal velocity of torso flexion and the linear velocity of moving the wrist joint forward, faster maximal velocity of head flexion, and smaller sway ratio compared with normally developed participants when throwing Boccia balls. Participants with CP seemed to mainly use head and shoulder movements to bring the Boccia balls forward with limited torso movement. Normally developed participants brought the Boccia ball forward with faster torso and greater elbow movement while stabilizing head and shoulder movements. Nevertheless, participants with CP did not demonstrate significantly worse performance in the throwing accuracy of Boccia balls. Copyright © 2013 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mortimer, P.S.; Simmonds, R.; Rezvani, M.
1990-12-01
The measurement of skin lymph flow was investigated using an isotope clearance technique (ICT). Multiple lymph flow determinations were undertaken in the skin of anaesthetized large white pigs to test for reproducibility, ascertain the most suitable tracer, study the influence of injection dynamics, and observe the effect of massage as a stimulus to lymph flow. Blood clearance of tracer was also investigated. Results demonstrated that lymphatic clearance is a monoexponential function with good reproducibility under controlled laboratory conditions. 99mTc-colloid (TCK17 Cis) compared favorably with 131I-human serum albumin as a tracer and both performed better than colloid gold (198Au). Lymph flowmore » was significantly faster in one pig than in the other. No difference existed between left and right sides or between caudal and rostral sites on each flank, but clearance was significantly slower in thigh than flank skin. Sub-epidermal injections cleared faster and more consistently than either deep or subcutaneous injections. Neither injection volume nor needle tract backflow of tracer influenced results, but local massage significantly enhanced clearance. Escape of 99mTc-colloid by the blood was negligible. These results indicate that skin lymph flow can be reliably measured when conditions are controlled. Extrinsic factors such as massage strongly influence lymph flow. Greater sensitivity in detecting degrees of lymphatic insufficiency may be achieved if a standardized stimulus to lymph flow is administered during isotope clearance measurement.« less
Phosphocreatine resynthesis during recovery in different muscles of the exercising leg by 31P-MRS.
Yoshida, T; Abe, D; Fukuoka, Y
2013-10-01
To investigate the high-energy phosphate metabolism by (31) P-nuclear magnetic resonance spectroscopy during off-transition of exercise in different muscle groups, such as calf muscles and biceps femoris muscles, seven male long-distance runners (LDR) and nine untrained males (UT) performed both submaximal constant and incremental exercises. The relative exercise intensity was set at 60% of the maximal work rate (60%W max) during both knee flexion and plantar flexion submaximal constant load exercises. The relative areas under the inorganic phosphate (Pi ) and phosphocreatine (PCr) peaks were determined. During the 5-min recovery following the 60%W max, the time constant for the PCr off-kinetics was significantly faster in the plantar flexion (LDR: 17.3 ± 3.6 s, UT: 26.7 ± 6.7 s) than in the knee flexion (LDR: 29.7 ± 4.7 s, UT: 42.7 ± 2.8 s, P < 0.05). In addition, a significantly faster PCr off-kinetics was observed in LDR than in UT for both exercises. The ratio of Pi to PCr (Pi /PCr) during exercise was significantly lower during the plantar flexion than during the knee flexion (P < 0.01). These findings indicated that the calf muscles had relatively higher potential for oxidative capacity than that of biceps femoris muscles with an association of training status. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
NASA Technical Reports Server (NTRS)
Chapanis, A.; Parrish, R. N.; Ochsman, R. B.; Weeks, G. D.
1977-01-01
Two-man teams solved credible, 'real world' problems for which computer assistance has been or could be useful. Conversations were carried on in one of four modes of communication: typewriting, handwriting, voice, and natural unrestricted communication. Performance was assessed on three classes of dependent measures: time to solution, behavioral measures of activity, and linguistic measures. Significant differences among the communication modes were found in each of the three classes. This paper is concerned mainly with the results of the linguistic analyses. Linguistic performance was assessed with 182 measures, most of which turned out to be redundant and some of which were useless or meaningless. Those that remain show that although problems can be solved faster in the oral modes than in the hard-copy modes, the oral modes are characterized by many more messages, sentences, words, and unique words; much higher communication rates; but lower type-token ratios. Although a number of significant problem and job-role effects were found, there were relatively few significant interactions of modes with thsse variables. It appears, therefore, that the mode effects hold for both problems and for both job roles assigned to the subjects.
The impact of crosstalk on three-dimensional laparoscopic performance and workload.
Sakata, Shinichiro; Grove, Philip M; Watson, Marcus O; Stevenson, Andrew R L
2017-10-01
This is the first study to explore the effects of crosstalk from 3D laparoscopic displays on technical performance and workload. We studied crosstalk at magnitudes that may have been tolerated during laparoscopic surgery. Participants were 36 voluntary doctors. To minimize floor effects, participants completed their surgery rotations, and a laparoscopic suturing course for surgical trainees. We used a counterbalanced, within-subjects design in which participants were randomly assigned to complete laparoscopic tasks in one of six unique testing sequences. In a simulation laboratory, participants were randomly assigned to complete laparoscopic 'navigation in space' and suturing tasks in three viewing conditions: 2D, 3D without ghosting and 3D with ghosting. Participants calibrated their exposure to crosstalk as the maximum level of ghosting that they could tolerate without discomfort. The Randot® Stereotest was used to verify stereoacuity. The study performance metric was time to completion. The NASA TLX was used to measure workload. Normal threshold stereoacuity (40-20 second of arc) was verified in all participants. Comparing optimal 3D with 2D viewing conditions, mean performance times were 2.8 and 1.6 times faster in laparoscopic navigation in space and suturing tasks respectively (p< .001). Comparing optimal 3D with suboptimal 3D viewing conditions, mean performance times were 2.9 times faster in both tasks (p< .001). Mean workload in 2D was 1.5 and 1.3 times greater than in optimal 3D viewing, for navigation in space and suturing tasks respectively (p< .001). Mean workload associated with suboptimal 3D was 1.3 times greater than optimal 3D in both laparoscopic tasks (p< .001). There was no significant relationship between the magnitude of ghosting score, laparoscopic performance and workload. Our findings highlight the advantages of 3D displays when used optimally, and their shortcomings when used sub-optimally, on both laparoscopic performance and workload.
Coyne, Joseph O C; Tran, Tai T; Secomb, Josh L; Lundgren, Lina E; Farley, Oliver R L; Newton, Robert U; Sheppard, Jeremy M
2017-01-01
Coyne, JOC, Tran, TT, Secomb, JL, Lundgren, LE, Farley, ORL, Newton, RU, and Sheppard, JM. Maximal strength training improves surfboard sprint and endurance paddling performance in competitive and recreational surfers. J Strength Cond Res 31(1): 244-253, 2017-Upper-body (UB) strength has very high correlations with faster surfboard paddling speeds. However, there is no research examining the effects of improving UB strength has on surfboard paddling ability. This study aimed to determine the influence that improvements in UB closed-kinetic chain maximal strength have on surfboard paddling in both competitive and recreational surfers. Seventeen competitive and recreational male surfers (29.7 ± 7.7 years, 177.4 ± 7.4 cm, 76.7 ± 9.9 kg) participated in a repeated-measures, parallel control study design. Anthropometry; 5-, 10-, and 15-m sprint; and 400-m endurance surfboard paddling tests along with pull-up and dip 1 repetition maximum strength tests were assessed pre- and postintervention. Subjects in the training group performed 5 weeks of maximal strength training in the pull-up and dip. Differences between the training and control groups were examined postintervention. The training group increased their speed over the 5-, 10-, and 15-m sprint, whereas the control group became slower (d = 0.71, 0.51, and 0.4, respectively). The training group also displayed faster endurance paddling performance compared with the control group (d = 0.72). Short-term exposure to maximal strength training elicits improvements in paddling performance measures. However, the magnitude of performance increases seems to be dependent on initial strength levels with differential responses between strong and weaker athletes. Although a longer maximal strength training period may have produced more significant paddling improvements in stronger subjects, practitioners are unlikely to have any more than 5 weeks in an uninterrupted block with competitive surfing athletes. This study reveals that a "threshold" level of maximal strength that if possessed, short-term maximal strength training may only provide little improvement in paddling performance.
A systematic review of cognitive decline in dementia with Lewy bodies versus Alzheimer’s disease
2014-01-01
Introduction The aim of this review was to investigate whether there is a faster cognitive decline in dementia with Lewy bodies (DLB) than in Alzheimer’s disease (AD) over time. Methods PsycINFO and Medline were searched from 1946 to February 2013. A quality rating from 1 to 15 (best) was applied to the included studies. A quantitative meta-analysis was done on studies with mini mental state examination (MMSE) as the outcome measure. Results A total of 18 studies were included. Of these, six (36%) reported significant differences in the rate of cognitive decline. Three studies reported a faster cognitive decline on MMSE in patients with mixed DLB and AD compared to pure forms, whereas two studies reported a faster decline on delayed recall and recognition in AD and one in DLB on verbal fluency. Mean quality scores for studies that did or did not differ were not significantly different. Six studies reported MMSE scores and were included in the meta-analysis, which showed no significant difference in annual decline on MMSE between DLB (mean 3.4) and AD (mean 3.3). Conclusions Our findings do not support the hypothesis of a faster rate of cognitive decline in DLB compared to AD. Future studies should apply recent diagnostic criteria, as well as extensive diagnostic evaluation and ideally autopsy diagnosis. Studies with large enough samples, detailed cognitive tests, at least two years follow up and multivariate statistical analysis are also needed. PMID:25478024
Net endogenous acid production is associated with a faster decline in GFR in African Americans
Scialla, Julia J.; Appel, Lawrence J.; Astor, Brad C.; Miller, Edgar R.; Beddhu, Srinivasan; Woodward, Mark; Parekh, Rulan S.; Anderson, Cheryl A. M.
2012-01-01
Increased acid excretion may promote renal injury. To evaluate this in African Americans with hypertensive nephrosclerosis, we studied the association between the net endogenous acid production and progression of kidney disease in 632 patients in the AASK trial. Protein and potassium intakes were estimated from 24-hour urea nitrogen and potassium excretion, and used to estimate net endogenous acid production, averaged over 2 years, approximating routine intake. The link between net endogenous acid production and the I125iothalamate glomerular filtration rate (iGFR) and time to end stage renal disease or doubling of serum creatinine was analyzed using mixed models and Cox proportional hazards regressions. The trend in higher net endogenous acid production was significantly associated with a faster decline in iGFR over a median of 3.2 years. After adjustment for age, body mass index, baseline iGFR, urine protein to creatinine ratio and randomized treatment group, the trend in higher net endogenous acid production remained significantly associated with a faster decline in iGFR at a rate 1.01 mL/min/1.73 m2 per year faster in the highest to the lowest quartile. However, in time to event analyses over a median of 7.7 years, the adjusted hazard ratio (1.10) for composite renal events per 25 mEq/day higher net endogenous acid production was not significant. Hence, our findings implicate endogenous acid production as a potential modifiable risk factor for progressive kidney disease. PMID:22475819
Connecting Performance Analysis and Visualization to Advance Extreme Scale Computing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bremer, Peer-Timo; Mohr, Bernd; Schulz, Martin
2015-07-29
The characterization, modeling, analysis, and tuning of software performance has been a central topic in High Performance Computing (HPC) since its early beginnings. The overall goal is to make HPC software run faster on particular hardware, either through better scheduling, on-node resource utilization, or more efficient distributed communication.
USE OF FAST GC/TOFMS AS REFERENCE STANDARD FOR FIELD COMPARISON STUDIES WITH ON-SITE INSTRUMENTS
A faster reference standard for field comparison studies of portable gas chromatographs (PGC) is needed. A performance evaluation of a high-speed GCMS (FGC/MS) system conducted during 1998 demonstrated generally satisfactory performance, but it was evident that performance of b...
Airplane tracking documents the fastest flight speeds recorded for bats.
McCracken, Gary F; Safi, Kamran; Kunz, Thomas H; Dechmann, Dina K N; Swartz, Sharon M; Wikelski, Martin
2016-11-01
The performance capabilities of flying animals reflect the interplay of biomechanical and physiological constraints and evolutionary innovation. Of the two extant groups of vertebrates that are capable of powered flight, birds are thought to fly more efficiently and faster than bats. However, fast-flying bat species that are adapted for flight in open airspace are similar in wing shape and appear to be similar in flight dynamics to fast-flying birds that exploit the same aerial niche. Here, we investigate flight behaviour in seven free-flying Brazilian free-tailed bats ( Tadarida brasiliensis ) and report that the maximum ground speeds achieved exceed speeds previously documented for any bat. Regional wind modelling indicates that bats adjusted flight speeds in response to winds by flying more slowly as wind support increased and flying faster when confronted with crosswinds, as demonstrated for insects, birds and other bats. Increased frequency of pauses in wing beats at faster speeds suggests that flap-gliding assists the bats' rapid flight. Our results suggest that flight performance in bats has been underappreciated and that functional differences in the flight abilities of birds and bats require re-evaluation.
Comparisons of population subgroups performance on a keyboard psychomotor task
NASA Technical Reports Server (NTRS)
Stapleford, R. L.
1973-01-01
Response time and pass/fail data were obtained from 163 subjects performing a psychomotor task. The basic task comprised a random five digit number briefly displayed to the subject at the start of each trail, and the keyboard on which the subject was to enter the number as fast as he could accurately do so after the display was extinguished. Some tests were run with the addition of a secondary task which required the subject to respond to a displayed light appearing at a random time. Matched pairs of subjects were selected from the group to analyze the effects of age, sex, intelligence, prior keyboard skill, and drinking habits. There was little or no effect due to age or drinking habits. Differences in response time were: average IQ subjects faster than low IQ subjects by 0.5 to 0.6 sec; subjects with prior keyboard skill faster by 0.4 to 0.5 sec; and female subjects faster by 0.2 to 0.3 sec. These effects were generally insensitive to the presence of the secondary task.
Prospective randomized controlled trial evaluating cap-assisted colonoscopy vs standard colonoscopy
Tee, Hoi-Poh; Corte, Crispin; Al-Ghamdi, Hamdan; Prakoso, Emilia; Darke, John; Chettiar, Raman; Rahman, Wassim; Davison, Scott; Griffin, Sean P; Selby, Warwick S; Kaffes, Arthur J
2010-01-01
AIM: To study the significance of cap-fitted colonoscopy in improving cecal intubation time and polyp detection rate. METHODS: This study was a prospective randomized controlled trial conducted from March 2008 to February 2009 in a tertiary referral hospital at Sydney. The primary end point was cecal intubation time and the secondary endpoint was polyp detection rate. Consecutive cases of total colonoscopy over a 1-year period were recruited. Randomization into either standard colonoscopy (SC) or cap-assisted colonoscopy (CAC) was performed after consent was obtained. For cases randomized to CAC, one of the three sizes of cap was used: D-201-15004 (with a diameter of 15.3 mm), D-201-14304 (14.6 mm) and D-201-12704 (13.0 mm). All of these caps were produced by Olympus Medical Systems, Japan. Independent predictors for faster cecal time and better polyp detection rate were also determined from this study. RESULTS: There were 200 cases in each group. There was no significant difference in terms of demographic characteristics between the two groups. CAC, when compared to the SC group, had no significant difference in terms of cecal intubation rate (96.0% vs 97.0%, P = 0.40) and time (9.94 ± 7.05 min vs 10.34 ± 6.82 min, P = 0.21), or polyp detection rate (32.8% vs 31.3%, P = 0.75). On the subgroup analysis, there was no significant difference in terms of cecal intubation time by trainees (88.1% vs 84.8%, P = 0.40), ileal intubation rate (82.5% vs 79.0%, P = 0.38) or total colonoscopy time (23.24 ± 13.95 min vs 22.56 ± 9.94 min, P = 0.88). On multivariate analysis, the independent determinants of faster cecal time were consultant-performed procedures (P < 0.001), male patients (P < 0.001), non-usage of hyoscine (P < 0.001) and better bowel preparation (P = 0.01). The determinants of better polyp detection rate were older age (P < 0.001), no history of previous abdominal surgery (P = 0.04), patients not having esophagogastroduodenoscopy in the same setting (P = 0.003), trainee-performed procedures (P = 0.01), usage of hyoscine (P = 0.01) and procedures performed for polyp follow-up (P = 0.01). The limitations of the study were that it was a single-center experience, no blinding was possible, and there were a large number of endoscopists. CONCLUSION: CAC did not significantly different from SC in term of cecal intubation time and polyp detection rate. PMID:20712051
Wong, J C H; Chung, C C; Yau, K K; Cheung, H Y S; Wong, D C T; Chan, O C Y; Li, M K W
2008-04-01
This study was designed to compare stapled vs. conventional hemorrhoidectomy for patients with acute thrombosed hemorrhoids. Forty-one patients with acute thrombosed hemorrhoids were randomized into: 1) stapled hemorrhoidectomy (PPH group; n = 21), and 2) open hemorrhoidectomy (open group; n = 20). Emergency surgery was performed with perioperative data and complications were recorded. Patients were followed up by independent assessors to evaluate pain, recurrence, continence function, and satisfaction at regular intervals. The median follow-up for the PPH group and open group were 59 and 56 weeks, respectively. There was no significant difference in terms of the hospital stay, complication rate, and continence function; however, the mean pain intensity in the first postoperative week was significantly less in the PPH group (4.1 vs. 5.7, P = 0.02). Patients in the PPH group recovered significantly faster in terms of the time to become analgesic-free (4 vs. 8.5 days, P < 0.01), time to become pain-free (9 vs. 20.5 days, P = 0.01), resumption of work (7 vs. 12.5 days, P = 0.01), and time for complete wound healing (2 vs. 4 weeks, P < 0.01). On long-term follow-up, significantly fewer patients in the PPH group complained of recurrent symptoms (0 vs. 5, P = 0.02). The overall symptom improvement and patients' satisfaction were significantly better in the PPH group (90 vs. 80 percent, P = 0.03 and +3 vs. +2, P < 0.01 respectively). Stapled hemorrhoidectomy is safe and effective for acute thrombosed hemorrhoids. Similar to elective stapled procedure, emergency stapled excision has greater short-term benefits compared with conventional excision: diminished pain, faster recovery, and earlier return to work. Long-term results and satisfaction were excellent.
Visual context modulates potentiation of grasp types during semantic object categorization.
Kalénine, Solène; Shapiro, Allison D; Flumini, Andrea; Borghi, Anna M; Buxbaum, Laurel J
2014-06-01
Substantial evidence suggests that conceptual processing of manipulable objects is associated with potentiation of action. Such data have been viewed as evidence that objects are recognized via access to action features. Many objects, however, are associated with multiple actions. For example, a kitchen timer may be clenched with a power grip to move it but pinched with a precision grip to use it. The present study tested the hypothesis that action evocation during conceptual object processing is responsive to the visual scene in which objects are presented. Twenty-five healthy adults were asked to categorize object pictures presented in different naturalistic visual contexts that evoke either move- or use-related actions. Categorization judgments (natural vs. artifact) were performed by executing a move- or use-related action (clench vs. pinch) on a response device, and response times were assessed as a function of contextual congruence. Although the actions performed were irrelevant to the categorization judgment, responses were significantly faster when actions were compatible with the visual context. This compatibility effect was largely driven by faster pinch responses when objects were presented in use-compatible, as compared with move-compatible, contexts. The present study is the first to highlight the influence of visual scene on stimulus-response compatibility effects during semantic object processing. These data support the hypothesis that action evocation during conceptual object processing is biased toward context-relevant actions.
Visual context modulates potentiation of grasp types during semantic object categorization
Kalénine, Solène; Shapiro, Allison D.; Flumini, Andrea; Borghi, Anna M.; Buxbaum, Laurel J.
2013-01-01
Substantial evidence suggests that conceptual processing of manipulable objects is associated with potentiation of action. Such data have been viewed as evidence that objects are recognized via access to action features. Many objects, however, are associated with multiple actions. For example, a kitchen timer may be clenched with a power grip to move it, but pinched with a precision grip to use it. The present study tested the hypothesis that action evocation during conceptual object processing is responsive to the visual scene in which objects are presented. Twenty-five healthy adults were asked to categorize object pictures presented in different naturalistic visual contexts that evoke either move- or use-related actions. Categorization judgments (natural vs. artifact) were performed by executing a move- or use-related action (clench vs. pinch) on a response device, and response times were assessed as a function of contextual congruence. Although the actions performed were irrelevant to the categorization judgment, responses were significantly faster when actions were compatible with the visual context. This compatibility effect was largely driven by faster pinch responses when objects were presented in use- compared to move-compatible contexts. The present study is the first to highlight the influence of visual scene on stimulus-response compatibility effects during semantic object processing. These data support the hypothesis that action evocation during conceptual object processing is biased toward context-relevant actions. PMID:24186270
Spacecraft attitude determination using a second-order nonlinear filter
NASA Technical Reports Server (NTRS)
Vathsal, S.
1987-01-01
The stringent attitude determination accuracy and faster slew maneuver requirements demanded by present-day spacecraft control systems motivate the development of recursive nonlinear filters for attitude estimation. This paper presents the second-order filter development for the estimation of attitude quaternion using three-axis gyro and star tracker measurement data. Performance comparisons have been made by computer simulation of system models and filter mechanization. It is shown that the second-order filter consistently performs better than the extended Kalman filter when the performance index of the root sum square estimation error of the quaternion vector is compared. The second-order filter identifies the gyro drift rates faster than the extended Kalman filter. The uniqueness of this algorithm is the online generation of the time-varying process and measurement noise covariance matrices, derived as a function or the process and measurement nonlinearity, respectively.
Design Alternatives to Improve Access Time Performance of Disk Drives Under DOS and UNIX
NASA Astrophysics Data System (ADS)
Hospodor, Andy
For the past 25 years, improvements in CPU performance have overshadowed improvements in the access time performance of disk drives. CPU performance has been slanted towards greater instruction execution rates, measured in millions of instructions per second (MIPS). However, the slant for performance of disk storage has been towards capacity and corresponding increased storage densities. The IBM PC, introduced in 1982, processed only a fraction of a MIP. Follow-on CPUs, such as the 80486 and 80586, sported 5-10 MIPS by 1992. Single user PCs and workstations, with one CPU and one disk drive, became the dominant application, as implied by their production volumes. However, disk drives did not enjoy a corresponding improvement in access time performance, although the potential still exists. The time to access a disk drive improves (decreases) in two ways: by altering the mechanical properties of the drive or by adding cache to the drive. This paper explores the improvement to access time performance of disk drives using cache, prefetch, faster rotation rates, and faster seek acceleration.
Comparison of nitrile gloves and nitrile over Nomex gloves.
Vorih, Deirdre Cronin; Bolton, Lauri D; Marcelynas, James; Nowicki, Thomas A; Jacobs, Lenworth; Robinson, Kenneth J
2009-01-01
Aeromedical flight crews must perform many tasks in flight requiring manual dexterity and fine precision. A common perception is that safety-enhancing fire-retardant gloves compromise patient care if worn during such tasks by providing added bulk and barrier to the hand. This study is a quantitative and qualitative analysis of this possible compromise to patient care. Sixteen practicing flight nurses and respiratory therapists were asked to perform 10 different standard patient care tasks while wearing either nitrile gloves or a nitrile-Nomex glove pair. Tasks were timed, rated as completed successfully or not, and were subsequently judged subjectively by the participants. Whereas the time required to insert an intravenous catheter and to insert a central line while wearing only nitrile gloves was significantly faster than when wearing both gloves, the time to perform all other tasks was not significantly different. In subjective ratings, the nitrile glove alone was scored significantly better than the two-glove combination by the study participants. Comfort, dexterity, tactile discrimination, and ease of use were all adversely affected by wearing a Nomex glove under a nitrile glove. Although the differences in times for most tasks may not be clinically significant, the difference in the subjective parameters may be great enough to cause helicopter emergency medical services (HEMS) practitioners to not wear Nomex gloves under nitrile gloves while performing procedures.
The Tubercles on Humpback Whales’ Flippers: Application of Bio-Inspired Technology
2011-05-01
mechanisms, while improving performance for lifting bodies in air and water. The tubercles on the leading edge can be applied to the design of...greater payloads and fly faster at higher altitudes than do small birds; race cars move faster over land than cheetahs , gazelles, or race horses...Fish and Battle 1995). Length varies from 0.25 to 0.33 of total body length (Tomilin 1957; Winn and Winn 1985; Edel and Winn 1978; Fish and Battle
Swimming performances in long distance open-water events with and without wetsuit
2014-01-01
Background Existing literature showed improved swimming performances for swimmers wearing wetsuits competing under standardized conditions in races held in pools on short to middle distances. Data about the influence of wetsuits on swimming performances in long and ultra-long open-water swimming races are missing. It is unknown whether the benefit of wearing wetsuits is comparable in men and women. The aim of this study was to investigate the influence of wearing a wetsuit on open-water swimming performances at the 26.4 km ‘Marathon Swim in Lake Zurich’ in Lake Zurich, Switzerland, and the 3.8 km Lake Ontario Swim Team-Race (LOST-Race) in Lake Ontario, Canada. Methods Race times of the fastest female and male swimmers competing with and without wetsuit were compared using multi-level regression analyses and analysis of variance. Results In the ‘Marathon Swim’ in Lake Zurich, wearing a wetsuit had no effect on race time regarding the gender where athletes wearing a wetsuit were not faster than athletes without wetsuit. However, the ten fastest men wearing a wetsuit (410.6 ± 26.7 min) were faster (32.7%, p < 0.01) than the ten fastest women without wetsuit (544.9 ± 81.3 min). In the ‘LOST-Race’, the top ten men wearing a wetsuit (51.7 ± 2.5 min) were faster (13.2%, p < 0.01) than the top ten women wearing a wetsuit (58.5 ± 3.2 min). Additionally, the top ten men without wetsuit (52.1 ± 2.4 min) were faster (19.6%, p < 0.01) than the top ten women without wetsuit (62.3 ± 2.5 min). The top ten women wearing a wetsuit (58.5 ± 3.2 min) were faster (6.5%, p < 0.01) than top ten women without a wetsuit (62.3 ± 25 min). Conclusions These results suggest that wearing a wetsuit had a positive influence on swimming speed for both women and men but the benefit of the use of wetsuits seemed to depend on additional factors (i.e. race distance). Women seemed to benefit more from wearing wetsuits than men in longer open-water ultra-distance swimming races. PMID:24891942
Risk perception influences athletic pacing strategy.
Micklewright, Dominic; Parry, David; Robinson, Tracy; Deacon, Greg; Renfree, Andrew; St Clair Gibson, Alan; Matthews, William J
2015-05-01
The objective of this study is to examine risk taking and risk perception associations with perceived exertion, pacing, and performance in athletes. Two experiments were conducted in which risk perception was assessed using the domain-specific risk taking (DOSPERT) scale in 20 novice cyclists (experiment 1) and 32 experienced ultramarathon runners (experiment 2). In experiment 1, participants predicted their pace and then performed a 5-km maximum effort cycling time trial on a calibrated Kingcycle mounted bicycle. Split times and perceived exertion were recorded every kilometer. In experiment 2, each participant predicted their split times before running a 100-km ultramarathon. Split times and perceived exertion were recorded at seven checkpoints. In both experiments, higher and lower risk perception groups were created using median split of DOSPERT scores. In experiment 1, pace during the first kilometer was faster among lower risk perceivers compared with higher risk perceivers (t(18) = 2.0, P = 0.03) and faster among higher risk takers compared with lower risk takers (t(18) = 2.2, P = 0.02). Actual pace was slower than predicted pace during the first kilometer in both the higher risk perceivers (t(9) = -4.2, P = 0.001) and lower risk perceivers (t(9) = -1.8, P = 0.049). In experiment 2, pace during the first 36 km was faster among lower risk perceivers compared with higher risk perceivers (t(16) = 2.0, P = 0.03). Irrespective of risk perception group, actual pace was slower than predicted pace during the first 18 km (t(16) = 8.9, P < 0.001) and from 18 to 36 km (t(16) = 4.0, P < 0.001). In both experiments, there was no difference in performance between higher and lower risk perception groups. Initial pace is associated with an individual's perception of risk, with low perceptions of risk being associated with a faster starting pace. Large differences between predicted and actual pace suggest that the performance template lacks accuracy, perhaps indicating greater reliance on momentary pacing decisions rather than preplanned strategy.
Improved FastICA algorithm in fMRI data analysis using the sparsity property of the sources.
Ge, Ruiyang; Wang, Yubao; Zhang, Jipeng; Yao, Li; Zhang, Hang; Long, Zhiying
2016-04-01
As a blind source separation technique, independent component analysis (ICA) has many applications in functional magnetic resonance imaging (fMRI). Although either temporal or spatial prior information has been introduced into the constrained ICA and semi-blind ICA methods to improve the performance of ICA in fMRI data analysis, certain types of additional prior information, such as the sparsity, has seldom been added to the ICA algorithms as constraints. In this study, we proposed a SparseFastICA method by adding the source sparsity as a constraint to the FastICA algorithm to improve the performance of the widely used FastICA. The source sparsity is estimated through a smoothed ℓ0 norm method. We performed experimental tests on both simulated data and real fMRI data to investigate the feasibility and robustness of SparseFastICA and made a performance comparison between SparseFastICA, FastICA and Infomax ICA. Results of the simulated and real fMRI data demonstrated the feasibility and robustness of SparseFastICA for the source separation in fMRI data. Both the simulated and real fMRI experimental results showed that SparseFastICA has better robustness to noise and better spatial detection power than FastICA. Although the spatial detection power of SparseFastICA and Infomax did not show significant difference, SparseFastICA had faster computation speed than Infomax. SparseFastICA was comparable to the Infomax algorithm with a faster computation speed. More importantly, SparseFastICA outperformed FastICA in robustness and spatial detection power and can be used to identify more accurate brain networks than FastICA algorithm. Copyright © 2016 Elsevier B.V. All rights reserved.
PhD7Faster: predicting clones propagating faster from the Ph.D.-7 phage display peptide library.
Ru, Beibei; 't Hoen, Peter A C; Nie, Fulei; Lin, Hao; Guo, Feng-Biao; Huang, Jian
2014-02-01
Phage display can rapidly discover peptides binding to any given target; thus, it has been widely used in basic and applied research. Each round of panning consists of two basic processes: Selection and amplification. However, recent studies have showed that the amplification step would decrease the diversity of phage display libraries due to different propagation capacity of phage clones. This may induce phages with growth advantage rather than specific affinity to appear in the final experimental results. The peptides displayed by such phages are termed as propagation-related target-unrelated peptides (PrTUPs). They would mislead further analysis and research if not removed. In this paper, we describe PhD7Faster, an ensemble predictor based on support vector machine (SVM) for predicting clones with growth advantage from the Ph.D.-7 phage display peptide library. By using reduced dipeptide composition (ReDPC) as features, an accuracy (Acc) of 79.67% and a Matthews correlation coefficient (MCC) of 0.595 were achieved in 5-fold cross-validation. In addition, the SVM-based model was demonstrated to perform better than several representative machine learning algorithms. We anticipate that PhD7Faster can assist biologists to exclude potential PrTUPs and accelerate the finding of specific binders from the popular Ph.D.-7 library. The web server of PhD7Faster can be freely accessed at http://immunet.cn/sarotup/cgi-bin/PhD7Faster.pl.
Hupfeld, K E; Ketcham, C J; Schneider, H D
2017-03-01
The supplementary motor area (SMA) is believed to be highly involved in the planning and execution of both simple and complex motor tasks. This study aimed to examine the role of the SMA in planning the movements required to complete reaction time, balance, and pegboard tasks using anodal transcranial direct current stimulation (tDCS), which passes a weak electrical current between two electrodes, in order to modulate neuronal activity. Twenty healthy adults were counterbalanced to receive either tDCS (experimental condition) or no tDCS (control condition) for 3 days. During administration of tDCS, participants performed a balance task significantly faster than controls. After tDCS, subjects significantly improved their simple and choice reaction time. These results demonstrate that the SMA is highly involved in planning and executing fine and gross motor skill tasks and that tDCS is an effective modality for increasing SMA-related performance on these tasks. The findings may be generalizable and therefore indicate implications for future interventions using tDCS as a therapeutic tool.
Aggregated channels network for real-time pedestrian detection
NASA Astrophysics Data System (ADS)
Ghorban, Farzin; Marín, Javier; Su, Yu; Colombo, Alessandro; Kummert, Anton
2018-04-01
Convolutional neural networks (CNNs) have demonstrated their superiority in numerous computer vision tasks, yet their computational cost results prohibitive for many real-time applications such as pedestrian detection which is usually performed on low-consumption hardware. In order to alleviate this drawback, most strategies focus on using a two-stage cascade approach. Essentially, in the first stage a fast method generates a significant but reduced amount of high quality proposals that later, in the second stage, are evaluated by the CNN. In this work, we propose a novel detection pipeline that further benefits from the two-stage cascade strategy. More concretely, the enriched and subsequently compressed features used in the first stage are reused as the CNN input. As a consequence, a simpler network architecture, adapted for such small input sizes, allows to achieve real-time performance and obtain results close to the state-of-the-art while running significantly faster without the use of GPU. In particular, considering that the proposed pipeline runs in frame rate, the achieved performance is highly competitive. We furthermore demonstrate that the proposed pipeline on itself can serve as an effective proposal generator.
Novel user interface design for medication reconciliation: an evaluation of Twinlist.
Plaisant, Catherine; Wu, Johnny; Hettinger, A Zach; Powsner, Seth; Shneiderman, Ben
2015-03-01
The primary objective was to evaluate time, number of interface actions, and accuracy on medication reconciliation tasks using a novel user interface (Twinlist, which lays out the medications in five columns based on similarity and uses animation to introduce the grouping - www.cs.umd.edu/hcil/sharp/twinlist) compared to a Control interface (where medications are presented side by side in two columns). A secondary objective was to assess participant agreement with statements regarding clarity and utility and to elicit comparisons. A 1 × 2 within-subjects experimental design was used with interface (Twinlist or Control) as an independent variable; time, number of clicks, scrolls, and errors were used as dependent variables. Participants were practicing medical providers with experience performing medication reconciliation but no experience with Twinlist. They reconciled two cases in each interface (in a counterbalanced order), then provided feedback on the design of the interface. Twenty medical providers participated in the study for a total of 80 trials. The trials using Twinlist were statistically significantly faster (18%), with fewer clicks (40%) and scrolls (60%). Serious errors were noted 12 and 31 times in Twinlist and Control trials, respectively. Trials using Twinlist were faster and more accurate. Subjectively, participants rated Twinlist more favorably than Control. They valued the novel layout of the drugs, but indicated that the included animation would be valuable for novices, but not necessarily for advanced users. Additional feedback from participants provides guidance for further development and clinical implementations. Cognitive support of medication reconciliation through interface design can significantly improve performance and safety. © The Author 2015. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Li, Yan; Ramírez-Valle, Francisco; Xue, Yongjun; Ventura, Judith I; Gouedard, Olivier; Mei, Jay; Takeshita, Kenichi; Palmisano, Maria; Zhou, Simon
2017-10-01
CC-292, a potent Bruton tyrosine kinase inhibitor, is under development for the treatment of B-cell malignancies. An analysis was performed to develop a population pharmacokinetic model of CC-292 and assess the influence of demographics and disease-related covariates on CC-292 exposure and to assess the exposure-response (overall response rate) relationship in patients with chronic lymphocytic leukemia. Population pharmacokinetic analysis was based on a 2-compartment base model conducted in NONMEM. Categorical exposure-response analysis was performed using logistic regression in SAS. The population pharmacokinetic analysis results indicated that CC-292 pharmacokinetic disposition is similar between healthy subjects and patients. CC-292 showed a larger central compartment volume of distribution than the peripheral compartment volume of distribution (158 L and 72 L, respectively) and a faster clearance than intercompartmental clearance (134 L/h and 18.7 L/h, respectively), indicating that for CC-292, clearance from blood occurs faster than distribution into deep tissues and organs. CC-292 clearance is not affected by demographics or baseline clinical lab factors, except for sex. Although sex significantly reduced variation of apparent clearance, the sex effect on apparent clearance is unlikely to be clinically relevant. The exposure-response analysis suggested that higher drug exposure is linearly correlated with higher overall response rate. A twice-daily dose regimen showed higher overall response rate as compared to once-daily dosing, consistent with a threshold concentration of approximately 300 ng/mL, above which the probability of overall response rate significantly increases. © 2017, The Authors. The Journal of Clinical Pharmacology Published by Wiley Periodicals, Inc. on behalf of American College of Clinical Pharmacology.
Riphaus, Andrea; Slottje, Mark; Bulla, Jan; Keil, Carolin; Mentzel, Christian; Limbach, Vera; Schultz, Barbara; Unzicker, Christian
2017-10-01
Sedation for colonoscopy using intravenous propofol has become standard in many Western countries. Gender-specific differences have been shown for general anaesthesia in dentistry, but no such data existed for gastrointestinal endoscopy. A prospective observational study. An academic teaching hospital of Hannover Medical School. A total of 219 patients (108 women and 111 men) scheduled for colonoscopy. Propofol sedation using electroencephalogram monitoring during a constant level of sedation depth (D0 to D2) performed by trained nurses or physicians after a body-weight-adjusted loading dose. The primary end-point was the presence of gender-specific differences in awakening time (time from end of sedation to eye-opening and complete orientation); secondary outcome parameters analysed were total dose of propofol, sedation-associated complications (bradycardia, hypotension, hypoxaemia and apnoea), patient cooperation and patient satisfaction. Multivariate analysis was performed to correct confounding factors such as age and BMI. Women awakened significantly faster than men, with a time to eye-opening of 7.3 ± 3.7 versus 8.4 ± 3.4 min (P = 0.005) and time until complete orientation of 9.1 ± 3.9 versus 10.4 ± 13.7 min (P = 0.008). The propofol dosage was not significantly different, with some trend towards more propofol per kg body weight in women (3.98 ± 1.81 mg versus 3.72 ± 1.75 mg, P = 0.232). The effect of gender aspects should be considered when propofol is used as sedation for gastrointestinal endoscopy. That includes adequate dosing for women as well as caution regarding potential overdosing of male patients. ClinicalTrials.gov (Identifier: NCT02687568).
The Faster, Better, Cheaper Approach to Space Missions: An Engineering Management Assessment
NASA Technical Reports Server (NTRS)
Hamaker, Joseph W.
1999-01-01
NASA was chartered as an independent civilian space agency in 1958 following the Soviet Union's dramatic launch of the Sputnik 1 (1957). In his state of the union address in May of 1961, President Kennedy issued to the fledging organization his famous challenge for a manned lunar mission by the end of the decade. The Mercury, Gemini and Apollo programs that followed put the utmost value on high quality, low risk (as low as possible within the context of space flight), quick results, all with little regard for cost. These circumstances essentially melded NASAs culture as an organization capable of great technological achievement but at extremely high cost. The Space Shuttle project, the next major agency endeavor, was put under severe annual budget constraints in the 1970's. NASAs response was to hold to the high quality standards, low risk and annual cost and let schedule suffer. The result was a significant delay in the introduction of the Shuttle as well as overall total cost growth. By the early 1990's, because NASA's budget was declining, the number of projects was also declining. Holding the same cost and schedule productivity levels as before was essentially causing NASA to price itself out of business. In 1992, the helm of NASA was turned over to a new Administrator. Dan Goldin's mantra was "faster, better, cheaper" and his enthusiasm and determination to change the NASA culture was not to be ignored. This research paper documents the various implementations of "faster, better, cheaper" that have been attempted, analyzes their impact and compares the cost performance of these new projects to previous NASA benchmarks. Fundamentally, many elements of "faster, better, cheaper" are found to be working well, especially on smaller projects. Some of the initiatives are found to apply only to smaller or experimental projects however, so that extrapolation to "flagship" projects may be problematic.
Validating New Software for Semiautomated Liver Volumetry--Better than Manual Measurement?
Noschinski, L E; Maiwald, B; Voigt, P; Wiltberger, G; Kahn, T; Stumpp, P
2015-09-01
This prospective study compared a manual program for liver volumetry with semiautomated software. The hypothesis was that the semiautomated software would be faster, more accurate and less dependent on the evaluator's experience. Ten patients undergoing hemihepatectomy were included in this IRB approved study after written informed consent. All patients underwent a preoperative abdominal 3-phase CT scan, which was used for whole liver volumetry and volume prediction for the liver part to be resected. Two different types of software were used: 1) manual method: borders of the liver had to be defined per slice by the user; 2) semiautomated software: automatic identification of liver volume with manual assistance for definition of Couinaud segments. Measurements were done by six observers with different experience levels. Water displacement volumetry immediately after partial liver resection served as the gold standard. The resected part was examined with a CT scan after displacement volumetry. Volumetry of the resected liver scan showed excellent correlation to water displacement volumetry (manual: ρ = 0.997; semiautomated software: ρ = 0.995). The difference between the predicted volume and the real volume was significantly smaller with the semiautomated software than with the manual method (33% vs. 57%, p = 0.002). The semiautomated software was almost four times faster for volumetry of the whole liver (manual: 6:59 ± 3:04 min; semiautomated: 1:47 ± 1:11 min). Both methods for liver volumetry give an estimated liver volume close to the real one. The tested semiautomated software is faster, more accurate in predicting the volume of the resected liver part, gives more reproducible results and is less dependent on the user's experience. Both tested types of software allow exact volumetry of resected liver parts. Preoperative prediction can be performed more accurately with the semiautomated software. The semiautomated software is nearly four times faster than the tested manual program and less dependent on the user's experience. © Georg Thieme Verlag KG Stuttgart · New York.
High Strain Rate Testing of Welded DOP-26 Iridium
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schneibel, J. H.; Miller, R. G.; Carmichael, C. A.
The iridium alloy DOP-26 is used to produce Clad Vent Set cups that protect the radioactive fuel in radioisotope thermoelectric generators (RTGs) which provide electric power for spacecraft and rovers. In a previous study, the tensile properties of DOP-26 were measured over a wide range of strain rates and temperatures and reported in ORNL/TM-2007/81. While that study established the properties of the base material, the fabrication of the heat sources requires welding, and the mechanical properties of welded DOP-26 have not been extensively characterized in the past. Therefore, this study was undertaken to determine the mechanical properties of DOP-26 specimensmore » containing a transverse weld in the center of their gage sections. Tensile tests were performed at room temperature, 750, 900, and 1090°C and engineering strain rates of 1×10 -3 and 10 s -1. Room temperature testing was performed in air, while testing at elevated temperatures was performed in a vacuum better than 1×10 -4 Torr. The welded specimens had a significantly higher yield stress, by up to a factor of ~2, than the non-welded base material. The yield stress did not depend on the strain rate except at 1090°C, where it was slightly higher for the faster strain rate. The ultimate tensile stress, on the other hand, was significantly higher for the faster strain rate at temperatures of 750°C and above. At 750°C and above, the specimens deformed at 1×10 -3 s -1 showed pronounced necking resulting sometimes in perfect chisel-edge fracture. The specimens deformed at 10 s -1 exhibited this fracture behavior only at the highest test temperature, 1090°C. Fracture occurred usually in the fusion zone of the weld and was, in most cases, primarily intergranular.« less
Wu, Wen-Lan; Wei, Ta-Sen; Chen, Shen-Kai; Chang, Jyh-Jong; Guo, Lan-Yuen; Lin, Hwai-Ting
2010-01-01
Walking performance changes with age. This has implications for the problem of falls in older adults. The aim of this study was to investigate the effects of Yuanji-Dance practice on walking balance and the associated attention demand in healthy elderly. Fifteen community-dwelling elderly (comparison group, no regular exercise habit) and fifteen Yuanji- Dance elderly (exercise group, dancing experience: 5.40 ± 1.95 years), aged 60-70 years, were included in this study. The subjects in exercise group participated in a 90-minute Yuanji-Dance practice at least three times per week and the comparison group continued their normal daily physical activity. Walking balance measures (including walking velocity, step length, step width, and percentage of time spent in double limb support, COM velocity and COM-COP inclination angles) and attentional demand tests (button reaction time and accuracy) were conducted under different conditions. Our results showed that stride lengths, walking velocities, peak A/P velocities (AP V) of the COM, medial COM-COP inclination (M angle) angles, reaction time, and accuracy decrease significantly as the dual-task (walking plus hand button pressing tasks) applied for either the comparison or exercise groups. These results demonstrated that walking performance is attenuated in our elderly participants as the cognitive tasks applied. Analysis also identified a significantly faster RT for our exercise group both in standing and walking conditions. This may indicate that physical exercise (Yuanji-Dance) may have facilitating effects on general cognitive and perceptual- motor functions. This implies that Chinese Yuanji-Dance practice for elderly adults may improve their personal safety when walking especially under the condition of multiple task demand. Key points The purpose of this study was to investigate the training effects of a Chinese traditional exercise, Yuanji-Dance, on walking balance and the associated attention demand in the healthy elderly. Walking performance is attenuated in elderly participants as the cognitive tasks applied. A significantly faster reaction time for our exercise group both in standing and walking conditions. Yuanji-Dance exercise training can improve the information processing speed of elderly people and has no influence of the dynamic walking balance. PMID:24149395
Randomized clinical trial of virtual reality simulation for laparoscopic skills training.
Grantcharov, T P; Kristiansen, V B; Bendix, J; Bardram, L; Rosenberg, J; Funch-Jensen, P
2004-02-01
This study examined the impact of virtual reality (VR) surgical simulation on improvement of psychomotor skills relevant to the performance of laparoscopic cholecystectomy. Sixteen surgical trainees performed a laparoscopic cholecystectomy on patients in the operating room (OR). The participants were then randomized to receive VR training (ten repetitions of all six tasks on the Minimally Invasive Surgical Trainer-Virtual Reality (MIST-VR)) or no training. Subsequently, all subjects performed a further laparoscopic cholecystectomy in the OR. Both operative procedures were recorded on videotape, and assessed by two independent and blinded observers using predefined objective criteria. Time to complete the procedure, error score and economy of movement score were assessed during the laparoscopic procedure in the OR. No differences in baseline variables were found between the two groups. Surgeons who received VR training performed laparoscopic cholecystectomy significantly faster than the control group (P=0.021). Furthermore, those who had VR training showed significantly greater improvement in error (P=0.003) and economy of movement (P=0.003) scores. Surgeons who received VR simulator training showed significantly greater improvement in performance in the OR than those in the control group. VR surgical simulation is therefore a valid tool for training of laparoscopic psychomotor skills and could be incorporated into surgical training programmes. Copyright 2003 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.
Schoenthaler, Martin; Avcil, Tuba; Sevcenco, Sabina; Nagele, Udo; Hermann, Thomas E W; Kuehhas, Franklin E; Shariat, Shahrokh F; Frankenschmidt, Alexander; Wetterauer, Ulrich; Miernik, Arkadiusz
2015-01-01
To evaluate the Single-Incision Transumbilical Surgery (SITUS) technique as compared to an established laparoendoscopic single-site surgery (LESS) technique (Single-Port Laparoscopic Surgery, SPLS) and conventional laparoscopy (CLS) in a surgical simulator model. Sixty-three medical students without previous laparoscopic experience were randomly assigned to one of the three groups (SITUS, SPLS and CLS). Subjects were asked to perform five standardized tasks of increasing difficulty adopted from the Fundamentals of Laparoscopic Surgery curriculum. Statistical evaluation included task completion times and accuracy. Overall performances of all tasks (except precision cutting) were significantly faster and of higher accuracy in the CLS and SITUS groups than in the SPLS group (p = 0.004 to p < 0.001). CLS and SITUS groups alone showed no significant difference in performance times and accuracy measurements for all tasks (p = 0.048 to p = 0.989). SITUS proved to be a simple, but highly effective technique to overcome restrictions of SPLS. In a surgical simulator model, novices were able to achieve task performances comparable to CLS and did significantly better than using a port-assisted LESS technique such as SPLS. The demonstrated advantages of SITUS may be attributed to a preservation of the basic principles of conventional laparoscopy, such as the use of straight instruments and an adequate degree of triangulation.
NASA Astrophysics Data System (ADS)
Kimball, Jorja; Cole, Bryan; Hobson, Margaret; Watson, Karan; Stanley, Christine
This paper reports findings on gender that were part of a larger study reviewing time to completion of course work that includes the first two semesters of calculus, chemistry, and physics, which are often considered the stumbling points or "barrier courses" to an engineering baccalaureate degree. Texas A&M University terms these courses core body of knowledge (CBK), and statistical analysis was conducted on two cohorts of first-year enrolling engineering students at the institution. Findings indicate that gender is statistically significantly related to completion of CBK with female engineering students completing required courses faster than males at the .01 level (p = 0.008). Statistical significance for gender and ethnicity was found between white male and white female students at the .01 level (p = 0.008). Descriptive analysis indicated that of the five majors studied (chemical, civil, computer, electrical, and mechanical engineering), women completed CBK faster than men, and African American and Hispanic women completed CBK faster than males of the same ethnicity.
What difference reveals about similarity.
Sagi, Eyal; Gentner, Dedre; Lovett, Andrew
2012-08-01
Detecting that two images are different is faster for highly dissimilar images than for highly similar images. Paradoxically, we showed that the reverse occurs when people are asked to describe how two images differ--that is, to state a difference between two images. Following structure-mapping theory, we propose that this disassociation arises from the multistage nature of the comparison process. Detecting that two images are different can be done in the initial (local-matching) stage, but only for pairs with low overlap; thus, "different" responses are faster for low-similarity than for high-similarity pairs. In contrast, identifying a specific difference generally requires a full structural alignment of the two images, and this alignment process is faster for high-similarity pairs. We described four experiments that demonstrate this dissociation and show that the results can be simulated using the Structure-Mapping Engine. These results pose a significant challenge for nonstructural accounts of similarity comparison and suggest that structural alignment processes play a significant role in visual comparison. Copyright © 2012 Cognitive Science Society, Inc.
Indirect addressing and load balancing for faster solution to Mandelbrot Set on SIMD architectures
NASA Technical Reports Server (NTRS)
Tomboulian, Sherryl
1989-01-01
SIMD computers with local indirect addressing allow programs to have queues and buffers, making certain kinds of problems much more efficient. Examined here are a class of problems characterized by computations on data points where the computation is identical, but the convergence rate is data dependent. Normally, in this situation, the algorithm time is governed by the maximum number of iterations required by each point. Using indirect addressing allows a processor to proceed to the next data point when it is done, reducing the overall number of iterations required to approach the mean convergence rate when a sufficiently large problem set is solved. Load balancing techniques can be applied for additional performance improvement. Simulations of this technique applied to solving Mandelbrot Sets indicate significant performance gains.
Parallel DSMC Solution of Three-Dimensional Flow Over a Finite Flat Plate
NASA Technical Reports Server (NTRS)
Nance, Robert P.; Wilmoth, Richard G.; Moon, Bongki; Hassan, H. A.; Saltz, Joel
1994-01-01
This paper describes a parallel implementation of the direct simulation Monte Carlo (DSMC) method. Runtime library support is used for scheduling and execution of communication between nodes, and domain decomposition is performed dynamically to maintain a good load balance. Performance tests are conducted using the code to evaluate various remapping and remapping-interval policies, and it is shown that a one-dimensional chain-partitioning method works best for the problems considered. The parallel code is then used to simulate the Mach 20 nitrogen flow over a finite-thickness flat plate. It is shown that the parallel algorithm produces results which compare well with experimental data. Moreover, it yields significantly faster execution times than the scalar code, as well as very good load-balance characteristics.
Integrality and separability of multitouch interaction techniques in 3D manipulation tasks.
Martinet, Anthony; Casiez, Géry; Grisoni, Laurent
2012-03-01
Multitouch displays represent a promising technology for the display and manipulation of data. While the manipulation of 2D data has been widely explored, 3D manipulation with multitouch displays remains largely unexplored. Based on an analysis of the integration and separation of degrees of freedom, we propose a taxonomy for 3D manipulation techniques with multitouch displays. Using that taxonomy, we introduce Depth-Separated Screen-Space (DS3), a new 3D manipulation technique based on the separation of translation and rotation. In a controlled experiment, we compared DS3 with Sticky Tools and Screen-Space. Results show that separating the control of translation and rotation significantly affects performance for 3D manipulation, with DS3 performing faster than the two other techniques.
Motivation in vigilance - Effects of self-evaluation and experimenter-controlled feedback.
NASA Technical Reports Server (NTRS)
Warm, J. S.; Kanfer, F. H.; Kuwada, S.; Clark, J. L.
1972-01-01
Vigilance experiments have been performed to study the relative efficiency of feedback operations in enhancing vigilance performance. Two feedback operations were compared - i.e., experimenter-controlled feedback in the form of knowledge of results (KR) regarding response times to signal detections, and subject-controlled feedback in the form of self-evaluation (SE) of response times to signal detections. The subjects responded to the aperiodic offset of a visual signal during a 1-hr vigil. Both feedback operations were found to enhance performance efficiency: subjects in the KR and SE conditions had faster response times than controls receiving no evaluative feedback. Moreover, the data of the KR and SE groups did not differ significantly from each other. The results are discussed in terms of the hypothesis that self-evaluation is a critical factor underlying the incentive value of KR in vigilance tasks.
Modeling node bandwidth limits and their effects on vector combining algorithms
DOE Office of Scientific and Technical Information (OSTI.GOV)
Littlefield, R.J.
Each node in a message-passing multicomputer typically has several communication links. However, the maximum aggregate communication speed of a node is often less than the sum of its individual link speeds. Such computers are called node bandwidth limited (NBL). The NBL constraint is important when choosing algorithms because it can change the relative performance of different algorithms that accomplish the same task. This paper introduces a model of communication performance for NBL computers and uses the model to analyze the overall performance of three algorithms for vector combining (global sum) on the Intel Touchstone DELTA computer. Each of the threemore » algorithms is found to be at least 33% faster than the other two for some combinations of machine size and vector length. The NBL constraint is shown to significantly affect the conditions under which each algorithm is fastest.« less
Chen, Xilin; Gestring, Mark L; Rosengart, Matthew R; Peitzman, Andrew B; Billiar, Timothy R; Sperry, Jason L; Brown, Joshua B
2018-05-04
Trauma is a time sensitive disease. Helicopter emergency medical services (HEMS) have shown benefit over ground EMS (GEMS), which may be related to reduced prehospital time. The distance at which this time benefit emerges depends on many factors that can vary across regions. Our objective was to determine the threshold distance at which HEMS has shorter prehospital time than GEMS under different conditions. Patients in the PA trauma registry 2000-2013 were included. Distance between zip centroid and trauma center was calculated using straight-line distance for HEMS and driving distance from GIS network analysis for GEMS. Contrast margins from linear regression identified the threshold distance at which HEMS had a significantly lower prehospital time than GEMS, indicated by non-overlapping 95% confidence intervals. The effect of peak traffic times and adverse weather on the threshold distance was evaluated. Geographic effects across EMS regions were also evaluated. A total of 144,741 patients were included with 19% transported by HEMS. Overall, HEMS became faster than GEMS at 7.7miles from the trauma center (p=0.043). HEMS became faster at 6.5miles during peak traffic (p=0.025) compared to 7.9miles during off-peak traffic (p=0.048). Adverse weather increased the distance at which HEMS was faster to 17.1miles (p=0.046) from 7.3miles in clear weather (p=0.036). Significant variation occurred across EMS regions, with threshold distances ranging from 5.4miles to 35.3miles. There was an inverse but non-significant relationship between urban population and threshold distance across EMS regions (ρ -0.351, p=0.28). This is the first study to demonstrate that traffic, weather, and geographic region significantly impact the threshold distance at which HEMS is faster than GEMS. HEMS was faster at shorter distances during peak traffic while adverse weather increased this distance. The threshold distance varied widely across geographic region. These factors must be considered to guide appropriate HEMS triage protocols. III, Therapeutic.
Muralha, Nuno; Oliveira, Manuel; Ferreira, Maria Amélia; Costa-Maia, José
2017-05-31
Virtual reality simulation is a topic of discussion as a complementary tool to traditional laparoscopic surgical training in the operating room. However, it is unclear whether virtual reality training can have an impact on the surgical performance of advanced laparoscopic procedures. Our objective was to assess the ability of the virtual reality simulator LAP Mentor to identify and quantify changes in surgical performance indicators, after LAP Mentor training for digestive anastomosis. Twelve surgeons from Centro Hospitalar de São João in Porto (Portugal) performed two sessions of advanced task 5: anastomosis in LAP Mentor, before and after completing the tutorial, and were evaluated on 34 surgical performance indicators. The results show that six surgical performance indicators significantly changed after LAP Mentor training. The surgeons performed the task significantly faster as the median 'total time' significantly reduced (p < 0.05) from 759.5 to 523.5 seconds. Significant decreases (p < 0.05) were also found in median 'total needle loading time' (303.3 to 107.8 seconds), 'average needle loading time' (38.5 to 31.0 seconds), 'number of passages in which the needle passed precisely through the entrance dots' (2.5 to 1.0), 'time the needle was held outside the visible field' (20.9 to 2.4 seconds), and 'total time the needle-holders' ends are kept outside the predefined operative field' (88.2 to 49.6 seconds). This study raises the possibility of using virtual reality training simulation as a benchmark tool to assess the surgical performance of Portuguese surgeons. LAP Mentor is able to identify variations in surgical performance indicators of digestive anastomosis.
Almeida, Renita A; Dickinson, J Edwin; Maybery, Murray T; Badcock, Johanna C; Badcock, David R
2010-12-01
The Embedded Figures Test (EFT) requires detecting a shape within a complex background and individuals with autism or high Autism-spectrum Quotient (AQ) scores are faster and more accurate on this task than controls. This research aimed to uncover the visual processes producing this difference. Previously we developed a search task using radial frequency (RF) patterns with controllable amounts of target/distracter overlap on which high AQ participants showed more efficient search than low AQ observers. The current study extended the design of this search task by adding two lines which traverse the display on random paths sometimes intersecting target/distracters, other times passing between them. As with the EFT, these lines segment and group the display in ways that are task irrelevant. We tested two new groups of observers and found that while RF search was slowed by the addition of segmenting lines for both groups, the high AQ group retained a consistent search advantage (reflected in a shallower gradient for reaction time as a function of set size) over the low AQ group. Further, the high AQ group were significantly faster and more accurate on the EFT compared to the low AQ group. That is, the results from the present RF search task demonstrate that segmentation and grouping created by intersecting lines does not further differentiate the groups and is therefore unlikely to be a critical factor underlying the EFT performance difference. However, once again, we found that superior EFT performance was associated with shallower gradients on the RF search task. Copyright © 2010 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nsakala, N.Y.; Patel, R.L.; Lao, T.C.
1982-09-01
The combustion and gasification kinetics of four size graded coal chars were investigated experimentally in Combustion Engineering's Drop Tube Furnace System (DTFS). The chars were prepared in the DTFS from commercially significant coals representing a wide range of rank; these included a Pittsburgh No. 8 Seam hvAb coal, an Illinois No. 6 Seam hvCb coal, a Wyoming Sub C, and a Texas Lignite A. Additionally, a number of standard ASTM and special bench scale tests were performed on the coals and chars to characterize their physicochemical properties. Results showed that the lower rank coal chars were more reactive than themore » higher rank coal chars and that combustion reactions of chars were much faster than the corresponding gasification reactions. Fuel properties, temperature, and reactant gas partial pressure had a significant influence on both combustion and gasification, and particle size had a mild but discernible influence on gasification. Fuel reactivities were closely related to pore structure. Computer simulation of the combustion and gasification performances of the subject samples in the DTFS supported the experimental findings.« less
Bun, Sok-Sithikun; Ayari, Anis; Latcu, Decebal Gabriel; Errahmouni, Abdelkarim; Saoudi, Nadir
2017-07-01
Remote magnetic navigation (RMN) and contact force (CF) sensing catheters are available technologies for radiofrequency (RF) catheter ablation of atrial fibrillation (AF). Our purpose was to compare time to electrogram (EGM) modification suggesting transmural lesions between RMN and CF-guided AF ablation. A total of 1,008 RF applications were analyzed in 21 patients undergoing RMN (n = 11) or CF-guided ablation (n = 10) for paroxysmal AF. All procedures were performed in sinus rhythm during general anesthesia. Time to EGM modification was measured until transmurality criteria were fulfilled: (1) complete disappearance of R if initial QR morphology; (2) diminution > 75% of R if initial QRS morphology; (3) complete disappearance of R' of initial RSR' morphology. Impedance drop as well as force time integral (FTI) were also assessed for each application. Mean CF at the beginning of each RF application in the CF group was 11 ± 2 g and mean FTI per application was 488 ± 163 gs. Time to EGM modification was significantly shorter in the RMN group (4.52 ± 0.1 seconds vs. 5.6 ± 0.09 seconds; P < 0.00001). There was no significant difference between other procedural parameters. Remote magnetic AF ablation is associated with faster EGM modification suggesting transmurality than optimized CF and FTI-guided catheter ablation. © 2017 Wiley Periodicals, Inc.
Looking and touching: what extant approaches reveal about the structure of early word knowledge.
Hendrickson, Kristi; Mitsven, Samantha; Poulin-Dubois, Diane; Zesiger, Pascal; Friend, Margaret
2015-09-01
The goal of the current study is to assess the temporal dynamics of vision and action to evaluate the underlying word representations that guide infants' responses. Sixteen-month-old infants participated in a two-alternative forced-choice word-picture matching task. We conducted a moment-by-moment analysis of looking and reaching behaviors as they occurred in tandem to assess the speed with which a prompted word was processed (visual reaction time) as a function of the type of haptic response: Target, Distractor, or No Touch. Visual reaction times (visual RTs) were significantly slower during No Touches compared to Distractor and Target Touches, which were statistically indistinguishable. The finding that visual RTs were significantly faster during Distractor Touches compared to No Touches suggests that incorrect and absent haptic responses appear to index distinct knowledge states: incorrect responses are associated with partial knowledge whereas absent responses appear to reflect a true failure to map lexical items to their target referents. Further, we found that those children who were faster at processing words were also those children who exhibited better haptic performance. This research provides a methodological clarification on knowledge measured by the visual and haptic modalities and new evidence for a continuum of word knowledge in the second year of life. © 2014 The Authors Developmental Science Published by John Wiley & Sons Ltd.
Yamaguchi, Shohei; Konishi, Kozo; Yasunaga, Takefumi; Yoshida, Daisuke; Kinjo, Nao; Kobayashi, Kiichiro; Ieiri, Satoshi; Okazaki, Ken; Nakashima, Hideaki; Tanoue, Kazuo; Maehara, Yoshihiko; Hashizume, Makoto
2007-12-01
This study was carried out to investigate whether eye-hand coordination skill on a virtual reality laparoscopic surgical simulator (the LAP Mentor) was able to differentiate among subjects with different laparoscopic experience and thus confirm its construct validity. A total of 31 surgeons, who were all right-handed, were divided into the following two groups according to their experience as an operator in laparoscopic surgery: experienced surgeons (more than 50 laparoscopic procedures) and novice surgeons (fewer than 10 laparoscopic procedures). The subjects were tested using the eye-hand coordination task of the LAP Mentor, and performance was compared between the two groups. Assessment of the laparoscopic skills was based on parameters measured by the simulator. The experienced surgeons completed the task significantly faster than the novice surgeons. The experienced surgeons also achieved a lower number of movements (NOM), better economy of movement (EOM) and faster average speed of the left instrument than the novice surgeons, whereas there were no significant differences between the two groups for the NOM, EOM and average speed of the right instrument. Eye-hand coordination skill of the nondominant hand, but not the dominant hand, measured using the LAP Mentor was able to differentiate between subjects with different laparoscopic experience. This study also provides evidence of construct validity for eye-hand coordination skill on the LAP Mentor.
Amaral, M B F; de Ávila, J M S; Abreu, M H G; Mesquita, R A
2015-11-01
Fibrous hyperplasia is treated by surgical incision using a scalpel, together with removal of the source of chronic trauma. However, scalpel techniques do not provide the haemostasis that is necessary when dealing with highly vascular tissues. Diode laser surgery can be used in the management of oral tissues due to its high absorption by water and haemoglobin, and has provided good results in both periodontal surgery and oral lesions. The aim of the present study was to compare the effects of diode laser surgery to those of the conventional technique in patients with fibrous hyperplasia. A randomized clinical trial was performed in which surgical and postoperative evaluations were analyzed. On comparison of the laser-treated (study group) patients to those treated with a scalpel (control group), significant differences were observed in the duration of surgery and the use of analgesic medications. Over a 3-week period, clinical healing of the postoperative wound was significantly faster in the control group as compared to the study group. In conclusion, diode laser surgery proved to be more effective and less invasive when compared to scalpel surgery in the management of fibrous hyperplasia. However, wound healing proved to be faster when using scalpel surgery. Copyright © 2015 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
Yong, Chul Soon; Sah, Hongkee; Jahng, Yurngdong; Chang, Hyeun Wook; Son, Jong-Keun; Lee, Seung Ho; Jeong, Tae Cheon; Rhee, Jong-Dal; Baek, Suk Hwan; Kim, Chong-Kook; Choi, Han-Gon
2003-05-01
Rectal poloxamer gel systems composed of poloxamers and bioadhesive polymers were easy to administer to the anus and were mucoadhesive to the rectal tissues without leakage after the dose. However, a poloxamer gel containing diclofenac sodium could not be developed using bioadhesive polymers, since the drug was precipitated in this preparation. To develop a poloxamer gel using sodium chloride instead of bioadhesive polymers, the physicochemical properties such as gelation temperature, gel strength, and bioadhesive force of various formulations composed of diclofenac sodium, poloxamers, and sodium chloride were investigated. Furthermore, the pharmacokinetic study of diclofenac sodium delivered by the poloxamer gel was performed. Diclofenac sodium significantly increased the gelation temperature and weakened the gel strength and bioadhesive force, while sodium chloride did the opposite. The poloxamer gels with less than 1.0% sodium chloride, in which the drug was not precipitated, were inserted into the rectum without difficulty and leakage, and were retained in the rectum of rats for at least 6 hr. Furthermore, poloxamer gel gave significantly higher initial plasma concentrations and faster Tmax of diclofenac sodium than did solid suppository, indicating that drug from poloxamer gel could be absorbed faster than that from the solid one in rats. Our results suggested that a rectal poloxamer gel system with sodium chloride and poloxamers was a more physically stable, convenient, and effective rectal dosage form for diclofenac sodium.
NASA Astrophysics Data System (ADS)
Stone, Christopher P.; Alferman, Andrew T.; Niemeyer, Kyle E.
2018-05-01
Accurate and efficient methods for solving stiff ordinary differential equations (ODEs) are a critical component of turbulent combustion simulations with finite-rate chemistry. The ODEs governing the chemical kinetics at each mesh point are decoupled by operator-splitting allowing each to be solved concurrently. An efficient ODE solver must then take into account the available thread and instruction-level parallelism of the underlying hardware, especially on many-core coprocessors, as well as the numerical efficiency. A stiff Rosenbrock and a nonstiff Runge-Kutta ODE solver are both implemented using the single instruction, multiple thread (SIMT) and single instruction, multiple data (SIMD) paradigms within OpenCL. Both methods solve multiple ODEs concurrently within the same instruction stream. The performance of these parallel implementations was measured on three chemical kinetic models of increasing size across several multicore and many-core platforms. Two separate benchmarks were conducted to clearly determine any performance advantage offered by either method. The first benchmark measured the run-time of evaluating the right-hand-side source terms in parallel and the second benchmark integrated a series of constant-pressure, homogeneous reactors using the Rosenbrock and Runge-Kutta solvers. The right-hand-side evaluations with SIMD parallelism on the host multicore Xeon CPU and many-core Xeon Phi co-processor performed approximately three times faster than the baseline multithreaded C++ code. The SIMT parallel model on the host and Phi was 13%-35% slower than the baseline while the SIMT model on the NVIDIA Kepler GPU provided approximately the same performance as the SIMD model on the Phi. The runtimes for both ODE solvers decreased significantly with the SIMD implementations on the host CPU (2.5-2.7 ×) and Xeon Phi coprocessor (4.7-4.9 ×) compared to the baseline parallel code. The SIMT implementations on the GPU ran 1.5-1.6 times faster than the baseline multithreaded CPU code; however, this was significantly slower than the SIMD versions on the host CPU or the Xeon Phi. The performance difference between the three platforms was attributed to thread divergence caused by the adaptive step-sizes within the ODE integrators. Analysis showed that the wider vector width of the GPU incurs a higher level of divergence than the narrower Sandy Bridge or Xeon Phi. The significant performance improvement provided by the SIMD parallel strategy motivates further research into more ODE solver methods that are both SIMD-friendly and computationally efficient.
Experimental system for measurement of radiologists' performance by visual search task.
Maeda, Eriko; Yoshikawa, Takeharu; Nakashima, Ryoichi; Kobayashi, Kazufumi; Yokosawa, Kazuhiko; Hayashi, Naoto; Masutani, Yoshitaka; Yoshioka, Naoki; Akahane, Masaaki; Ohtomo, Kuni
2013-01-01
Detective performance of radiologists for "obvious" targets should be evaluated by visual search task instead of ROC analysis, but visual task have not been applied to radiology studies. The aim of this study was to set up an environment that allows visual search task in radiology, to evaluate its feasibility, and to preliminarily investigate the effect of career on the performance. In a darkroom, ten radiologists were asked to answer the type of lesion by pressing buttons, when images without lesions, with bulla, ground-glass nodule, and solid nodule were randomly presented on a display. Differences in accuracy and reaction times depending on board certification were investigated. The visual search task was successfully and feasibly performed. Radiologists were found to have high sensitivity, specificity, positive predictive values and negative predictive values in non-board and board groups. Reaction time was under 1 second for all target types in both groups. Board radiologists were significantly faster in answering for bulla, but there were no significant differences for other targets and values. We developed an experimental system that allows visual search experiment in radiology. Reaction time for detection of bulla was shortened with experience.
Initial Progress Rates as Related to Performance in a Personalized System of Instruction
ERIC Educational Resources Information Center
Henneberry, John K.
1976-01-01
Discusses research which explored the hypothesis that students who are fast starters in a personalized system of instruction psychology course would perform better and maintain faster course progress rates than slow starters. Findings indicate that students' starting pace is predictive of course performance and subsequent progress rates.…
Fluctuations in Elementary School Children's Working Memory Performance in the School Context
ERIC Educational Resources Information Center
Dirk, Judith; Schmiedek, Florian
2016-01-01
Children experience good and bad days in their performance. Although this phenomenon is well-known to teachers, parents, and students it has not been investigated empirically. We examined whether children's working memory performance varies systematically from day to day and to which extent fluctuations at faster timescales (i.e., occasions,…
Multicore Programming Challenges
NASA Astrophysics Data System (ADS)
Perrone, Michael
The computer industry is facing fundamental challenges that are driving a major change in the design of computer processors. Due to restrictions imposed by quantum physics, one historical path to higher computer processor performance - by increased clock frequency - has come to an end. Increasing clock frequency now leads to power consumption costs that are too high to justify. As a result, we have seen in recent years that the processor frequencies have peaked and are receding from their high point. At the same time, competitive market conditions are giving business advantage to those companies that can field new streaming applications, handle larger data sets, and update their models to market conditions faster. The desire for newer, faster and larger is driving continued demand for higher computer performance.
Double hashing technique in closed hashing search process
NASA Astrophysics Data System (ADS)
Rahim, Robbi; Zulkarnain, Iskandar; Jaya, Hendra
2017-09-01
The search process is used in various activities performed both online and offline, many algorithms that can be used to perform the search process one of which is a hash search algorithm, search process with hash search algorithm used in this study using double hashing technique where the data will be formed into the table with same length and then search, the results of this study indicate that the search process with double hashing technique allows faster searching than the usual search techniques, this research allows to search the solution by dividing the value into the main table and overflow table so that the search process is expected faster than the data stacked in the form of one table and collision data could avoided.
Light at Night and Measures of Alertness and Performance: Implications for Shift Workers.
Figueiro, Mariana G; Sahin, Levent; Wood, Brittany; Plitnick, Barbara
2016-01-01
Rotating-shift workers, particularly those working at night, are likely to experience sleepiness, decreased productivity, and impaired safety while on the job. Light at night has been shown to have acute alerting effects, reduce sleepiness, and improve performance. However, light at night can also suppress melatonin and induce circadian disruption, both of which have been linked to increased health risks. Previous studies have shown that long-wavelength (red) light exposure increases objective and subjective measures of alertness at night, without suppressing nocturnal melatonin. This study investigated whether exposure to red light at night would not only increase measures of alertness but also improve performance. It was hypothesized that exposure to both red (630 nm) and white (2,568 K) lights would improve performance but that only white light would significantly affect melatonin levels. Seventeen individuals participated in a 3-week, within-subjects, nighttime laboratory study. Compared to remaining in dim light, participants had significantly faster reaction times in the GO/NOGO test after exposure to both red light and white light. Compared to dim light exposure, power in the alpha and alpha-theta regions was significantly decreased after exposure to red light. Melatonin levels were significantly suppressed by white light only. Results show that not only can red light improve measures of alertness, but it can also improve certain types of performance at night without affecting melatonin levels. These findings could have significant practical applications for nurses; red light could help nurses working rotating shifts maintain nighttime alertness, without suppressing melatonin or changing their circadian phase. © The Author(s) 2015.
Tüzün, Nedim; Op de Beeck, Lin; Brans, Kristien I; Janssens, Lizanne; Stoks, Robby
2017-12-01
The rapidly increasing rate of urbanization has a major impact on the ecology and evolution of species. While increased temperatures are a key aspect of urbanization ("urban heat islands"), we have very limited knowledge whether this generates differentiation in thermal responses between rural and urban populations. In a common garden experiment, we compared the thermal performance curves (TPCs) for growth rate and mortality in larvae of the damselfly Coenagrion puella from three urban and three rural populations. TPCs for growth rate shifted vertically, consistent with the faster-slower theoretical model whereby the cold-adapted rural larvae grew faster than the warm-adapted urban larvae across temperatures. In line with costs of rapid growth, rural larvae showed lower survival than urban larvae across temperatures. The relatively lower temperatures hence expected shorter growing seasons in rural populations compared to the populations in the urban heat islands likely impose stronger time constraints to reach a certain developmental stage before winter, thereby selecting for faster growth rates. In addition, higher predation rates at higher temperature may have contributed to the growth rate differences between urban and rural ponds. A faster-slower differentiation in TPCs may be a widespread pattern along the urbanization gradient. The observed microgeographic differentiation in TPCs supports the view that urbanization may drive life-history evolution. Moreover, because of the urban heat island effect, urban environments have the potential to aid in developing predictions on the impact of climate change on rural populations.
Periodontal tissue healing following flap surgery using an Er:YAG laser in dogs.
Mizutani, Koji; Aoki, Akira; Takasaki, Aristeo Atsushi; Kinoshita, Atsuhiro; Hayashi, Chie; Oda, Shigeru; Ishikawa, Isao
2006-04-01
The purpose of this study was to compare periodontal tissue healing following flap surgery using an Er:YAG laser with that of conventional surgery. Bilateral premolars with experimentally induced periodontitis in six dogs were treated by periodontal flap surgery. Degranulation and root debridement in the furcation were performed using an Er:YAG laser or curet. At 3 months postsurgery, animals were sacrificed and decalcified specimens were prepared for histological and histometric analysis. Degranulation and root debridement were effectively performed with an Er:YAG laser without major thermal damage and significantly faster than with a curet. Histologically, the amount of newly formed bone was significantly greater in the laser group than in the curet group, although both groups showed similar amounts of cementum formation and connective tissue attachment. The Er:YAG laser irradiation can be safely and effectively utilized in periodontal flap surgery, and has the potential to promote new bone formation. Copyright 2006 Wiley-Liss, Inc.
Elith, Craig A; Dempsey, Shane E; Warren-Forward, Helen M
2013-01-01
Introduction The primary aim of this study is to compare intensity modulated radiation therapy (IMRT) to volumetric modulated arc therapy (VMAT) for the radical treatment of prostate cancer using version 10.0 (v10.0) of Varian Medical Systems, RapidArc radiation oncology system. Particular focus was placed on plan quality and the implications on departmental resources. The secondary objective was to compare the results in v10.0 to the preceding version 8.6 (v8.6). Methods Twenty prostate cancer cases were retrospectively planned using v10.0 of Varian's Eclipse and RapidArc software. Three planning techniques were performed: a 5-field IMRT, VMAT using one arc (VMAT-1A), and VMAT with two arcs (VMAT-2A). Plan quality was assessed by examining homogeneity, conformity, the number of monitor units (MUs) utilized, and dose to the organs at risk (OAR). Resource implications were assessed by examining planning and treatment times. The results obtained using v10.0 were also compared to those previously reported by our group for v8.6. Results In v10.0, each technique was able to produce a dose distribution that achieved the departmental planning guidelines. The IMRT plans were produced faster than VMAT plans and displayed improved homogeneity. The VMAT plans provided better conformity to the target volume, improved dose to the OAR, and required fewer MUs. Treatments using VMAT-1A were significantly faster than both IMRT and VMAT-2A. Comparison between versions 8.6 and 10.0 revealed that in the newer version, VMAT planning was significantly faster and the quality of the VMAT dose distributions produced were of a better quality. Conclusion VMAT (v10.0) using one or two arcs provides an acceptable alternative to IMRT for the treatment of prostate cancer. VMAT-1A has the greatest impact on reducing treatment time. PMID:26229615
Hout, Michael C; Goldinger, Stephen D
2012-02-01
When observers search for a target object, they incidentally learn the identities and locations of "background" objects in the same display. This learning can facilitate search performance, eliciting faster reaction times for repeated displays. Despite these findings, visual search has been successfully modeled using architectures that maintain no history of attentional deployments; they are amnesic (e.g., Guided Search Theory). In the current study, we asked two questions: 1) under what conditions does such incidental learning occur? And 2) what does viewing behavior reveal about the efficiency of attentional deployments over time? In two experiments, we tracked eye movements during repeated visual search, and we tested incidental memory for repeated nontarget objects. Across conditions, the consistency of search sets and spatial layouts were manipulated to assess their respective contributions to learning. Using viewing behavior, we contrasted three potential accounts for faster searching with experience. The results indicate that learning does not result in faster object identification or greater search efficiency. Instead, familiar search arrays appear to allow faster resolution of search decisions, whether targets are present or absent.
High blood pressure and cognitive decline in mild cognitive impairment.
Goldstein, Felicia C; Levey, Allan I; Steenland, N Kyle
2013-01-01
To determine whether high blood pressure (BP) levels are associated with faster decline in specific cognitive domains. Prospective longitudinal cohort. Uniform Data Set of the National Institutes of Health, National Institute on Aging Alzheimer's Disease Centers. One thousand three hundred eighty-five participants with a diagnosis of mild cognitive impairment (MCI) and measured BP values at baseline and two annual follow-up visits. Neuropsychological test scores and Clinical Dementia Rating Sum of Boxes (CDR Sum) score. Participants with MCI with two or three annual occasions of high BP values (systolic BP ≥140 mmHg or diastolic BP ≥90 mmHg) had significantly faster decline on neuropsychological measures of visuomotor sequencing, set shifting, and naming than those who were normotensive on all three occasions. High systolic BP values were associated as well with faster decline on the CDR Sum score. Hypertension is associated with faster cognitive decline in persons at risk for dementia. © 2012, Copyright the Authors Journal compilation © 2012, The American Geriatrics Society.
High Blood Pressure and Cognitive Decline in Mild Cognitive Impairment
Goldstein, Felicia C.; Levey, Allan I.; Steenland, N. Kyle
2013-01-01
Objectives To determine whether high blood pressure (BP) levels are associated with faster decline in specific cognitive domains. Design Prospective longitudinal cohort. Setting Uniform Data Set of the National Institutes of Health, National Institute on Aging Alzheimer's Disease Centers. Participants One thousand three hundred eighty-five participants with a diagnosis of mild cognitive impairment (MCI) and measured BP values at baseline and two annual follow-up visits. Measurements Neuropsychological test scores and Clinical Dementia Rating Sum of Boxes (CDR Sum) score. Results Participants with MCI with two or three annual occasions of high BP values (systolic BP ≥ 140 mmHg or diastolic BP ≥ 90 mmHg) had significantly faster decline on neuropsychological measures of visuomotor sequencing, set shifting, and naming than those who were normotensive on all three occasions. High systolic BP values were associated as well with faster decline on the CDR Sum score. Conclusion Hypertension is associated with faster cognitive decline in persons at risk for dementia. PMID:23301925
Faster-X evolution: Theory and evidence from Drosophila.
Charlesworth, Brian; Campos, José L; Jackson, Benjamin C
2018-02-12
A faster rate of adaptive evolution of X-linked genes compared with autosomal genes can be caused by the fixation of recessive or partially recessive advantageous mutations, due to the full expression of X-linked mutations in hemizygous males. Other processes, including recombination rate and mutation rate differences between X chromosomes and autosomes, may also cause faster evolution of X-linked genes. We review population genetics theory concerning the expected relative values of variability and rates of evolution of X-linked and autosomal DNA sequences. The theoretical predictions are compared with data from population genomic studies of several species of Drosophila. We conclude that there is evidence for adaptive faster-X evolution of several classes of functionally significant nucleotides. We also find evidence for potential differences in mutation rates between X-linked and autosomal genes, due to differences in mutational bias towards GC to AT mutations. Many aspects of the data are consistent with the male hemizygosity model, although not all possible confounding factors can be excluded. © 2018 John Wiley & Sons Ltd.
Kaufmann, Amanda; Hitsman, Brian; Goelz, Patricia M; Veluz-Wilkins, Anna; Blazekovic, Sonja; Powers, Lindsay; Leone, Frank T; Gariti, Peter; Tyndale, Rachel F; Schnoll, Robert A
2015-12-01
In samples from controlled randomized clinical trials, a smoker's rate of nicotine metabolism, measured by the 3-hydroxycotinine to cotinine ratio (NMR), predicts response to transdermal nicotine. Replication of this relationship in community-based samples of treatment-seeking smokers may help guide the implementation of the NMR for personalized treatment for nicotine dependence. Data from a community-based sample of treatment seeking smokers (N=499) who received 8weeks of transdermal nicotine and 4 behavioral counseling sessions were used to evaluate associations between the NMR and smoking cessation. Secondary outcomes included withdrawal and craving, depression and anxiety, side effects, and treatment adherence. The NMR was a significant predictor of abstinence (OR=.56, 95% CI: 0.33-0.95, p=.03), with faster metabolizers showing lower quit rates than slower metabolizers (24% vs. 33%). Faster nicotine metabolizers exhibited significantly higher levels of anxiety symptoms over time during treatment, vs. slower metabolizers (NMR x Time interaction: F[3,357]=3.29, p=.02). NMR was not associated with changes in withdrawal, craving, depression, side effects, and treatment adherence (p's>.05). In a community-based sample of treatment-seeking smokers, faster nicotine metabolizers were significantly less likely to quit smoking and showed higher rates of anxiety symptoms during a smoking cessation treatment program, vs. slower nicotine metabolizers. These results provide further evidence that transdermal nicotine is less effective for faster nicotine metabolizers and suggest the need to address cessation-induced anxiety symptoms among these smokers to increase the chances for successful smoking cessation. Copyright © 2015 Elsevier Ltd. All rights reserved.
Chen, David D; Pei, Laura; Chan, John S Y; Yan, Jin H
2012-10-01
Recent research using deliberate amplification of spatial errors to increase motor learning leads to the question of whether amplifying temporal errors may also facilitate learning. We investigated transfer effects caused by manipulating temporal constraints on learning a two-choice reaction time (CRT) task with varying degrees of stimulus-response compatibility. Thirty-four participants were randomly assigned to one of the three groups and completed 120 trials during acquisition. For every fourth trial, one group was instructed to decrease CRT by 50 msec. relative to the previous trial and a second group was instructed to increase CRT by 50 msec. The third group (the control) was told not to change their responses. After a 5-min. break, participants completed a 40-trial no-feedback transfer test. A 40-trial delayed transfer test was administered 24 hours later. During acquisition, the Decreased Reaction Time group responded faster than the two other groups, but this group also made more errors than the other two groups. In the 5-min. delayed test (immediate transfer), the Decreased Reaction Time group had faster reaction times than the other two groups, while for the 24-hr. delayed test (delayed transfer), both the Decreased Reaction Time group and Increased Reaction Time group had significantly faster reaction times than the control. For delayed transfer, both Decreased and Increased Reaction Time groups reacted significantly faster than the control group. Analyses of error scores in the transfer tests indicated revealed no significant group differences. Results were discussed with regard to the notion of practice variability and goal-setting benefits.
Design of ultra high performance concrete as an overlay in pavements and bridge decks.
DOT National Transportation Integrated Search
2014-08-01
The main objective of this research was to develop ultra-high performance concrete (UHPC) as a reliable, economic, low carbon foot : print and durable concrete overlay material that can offer shorter traffic closures due to faster construction. The U...
When does Iconicity in Sign Language Matter?
Baus, Cristina; Carreiras, Manuel; Emmorey, Karen
2012-01-01
We examined whether iconicity in American Sign Language (ASL) enhances translation performance for new learners and proficient signers. Fifteen hearing nonsigners and 15 proficient ASL-English bilinguals performed a translation recognition task and a production translation task. Nonsigners were taught 28 ASL verbs (14 iconic; 14 non-iconic) prior to performing these tasks. Only new learners benefited from sign iconicity, recognizing iconic translations faster and more accurately and exhibiting faster forward (English-ASL) and backward (ASL-English) translation times for iconic signs. In contrast, proficient ASL-English bilinguals exhibited slower recognition and translation times for iconic signs. We suggest iconicity aids memorization in the early stages of adult sign language learning, but for fluent L2 signers, iconicity interacts with other variables that slow translation (specifically, the iconic signs had more translation equivalents than the non-iconic signs). Iconicity may also have slowed translation performance by forcing conceptual mediation for iconic signs, which is slower than translating via direct lexical links. PMID:23543899
Clawson, Ann; Clayson, Peter E; Keith, Cierra M; Catron, Christina; Larson, Michael J
2017-03-01
Cognitive control includes higher-level cognitive processes used to evaluate environmental conflict. Given the importance of cognitive control in regulating behavior, understanding the developmental course of these processes may contribute to a greater understanding of normal and abnormal development. We examined behavioral (response times [RTs], error rates) and event-related potential data (N2, error-related negativity [ERN], correct-response negativity [CRN], error positivity [Pe]) during a flanker task in cross-sectional groups of 45 youth (ages 8-18), 52 younger adults (ages 20-28), and 58 older adults (ages 56-91). Younger adults displayed the most efficient processing, including significantly reduced CRN and N2 amplitude, increased Pe amplitude, and significantly better task performance than youth or older adults (e.g., faster RTs, fewer errors). Youth displayed larger CRN and N2, attenuated Pe, and significantly worse task performance than younger adults. Older adults fell either between youth and younger adults (e.g., CRN amplitudes, N2 amplitudes) or displayed neural and behavioral performance that was similar to youth (e.g., Pe amplitudes, error rates). These findings point to underdeveloped neural and cognitive processes early in life and reduced efficiency in older adulthood, contributing to poor implementation and modulation of cognitive control in response to conflict. Thus, cognitive control processing appears to reach peak performance and efficiency in younger adulthood, marked by improved task performance with less neural activation. Copyright © 2017 Elsevier B.V. All rights reserved.
Fully Convolutional Networks for Ground Classification from LIDAR Point Clouds
NASA Astrophysics Data System (ADS)
Rizaldy, A.; Persello, C.; Gevaert, C. M.; Oude Elberink, S. J.
2018-05-01
Deep Learning has been massively used for image classification in recent years. The use of deep learning for ground classification from LIDAR point clouds has also been recently studied. However, point clouds need to be converted into an image in order to use Convolutional Neural Networks (CNNs). In state-of-the-art techniques, this conversion is slow because each point is converted into a separate image. This approach leads to highly redundant computation during conversion and classification. The goal of this study is to design a more efficient data conversion and ground classification. This goal is achieved by first converting the whole point cloud into a single image. The classification is then performed by a Fully Convolutional Network (FCN), a modified version of CNN designed for pixel-wise image classification. The proposed method is significantly faster than state-of-the-art techniques. On the ISPRS Filter Test dataset, it is 78 times faster for conversion and 16 times faster for classification. Our experimental analysis on the same dataset shows that the proposed method results in 5.22 % of total error, 4.10 % of type I error, and 15.07 % of type II error. Compared to the previous CNN-based technique and LAStools software, the proposed method reduces the total error and type I error (while type II error is slightly higher). The method was also tested on a very high point density LIDAR point clouds resulting in 4.02 % of total error, 2.15 % of type I error and 6.14 % of type II error.
Melon yield prediction using small unmanned aerial vehicles
NASA Astrophysics Data System (ADS)
Zhao, Tiebiao; Wang, Zhongdao; Yang, Qi; Chen, YangQuan
2017-05-01
Thanks to the development of camera technologies, small unmanned aerial systems (sUAS), it is possible to collect aerial images of field with more flexible visit, higher resolution and much lower cost. Furthermore, the performance of objection detection based on deeply trained convolutional neural networks (CNNs) has been improved significantly. In this study, we applied these technologies in the melon production, where high-resolution aerial images were used to count melons in the field and predict the yield. CNN-based object detection framework-Faster R-CNN is applied in the melon classification. Our results showed that sUAS plus CNNs were able to detect melons accurately in the late harvest season.
Multiband Photonic Phased-Array Antenna
NASA Technical Reports Server (NTRS)
Tang, Suning
2015-01-01
A multiband phased-array antenna (PAA) can reduce the number of antennas on shipboard platforms while offering significantly improved performance. Crystal Research, Inc., has developed a multiband photonic antenna that is based on a high-speed, optical, true-time-delay beamformer. It is capable of simultaneously steering multiple independent radio frequency (RF) beams in less than 1,000 nanoseconds. This high steering speed is 3 orders of magnitude faster than any existing optical beamformer. Unlike other approaches, this technology uses a single controlling device per operation band, eliminating the need for massive optical switches, laser diodes, and fiber Bragg gratings. More importantly, only one beamformer is needed for all antenna elements.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Huang, Xiaobiao; Safranek, James
2014-09-01
Nonlinear dynamics optimization is carried out for a low emittance upgrade lattice of SPEAR3 in order to improve its dynamic aperture and Touschek lifetime. Two multi-objective optimization algorithms, a genetic algorithm and a particle swarm algorithm, are used for this study. The performance of the two algorithms are compared. The result shows that the particle swarm algorithm converges significantly faster to similar or better solutions than the genetic algorithm and it does not require seeding of good solutions in the initial population. These advantages of the particle swarm algorithm may make it more suitable for many accelerator optimization applications.
Variations in Carboxyhaemoglobin Levels in Smokers
Castleden, C. M.; Cole, P. V.
1974-01-01
Three experiments on smokers have been performed to determine variations in blood levels of carboxyhaemoglobin (COHb) throughout the day and night and whether a random measurement of COHb gives a true estimation of a smoker's mean COHb level. In the individual smoker the COHb level does not increase gradually during the day but is kept within relatively narrow limits. Moderately heavy smokers rise in the morning with a substantially raised COHb level because the half life of COHb is significantly longer during sleep than during the day. Women excrete their carbon monoxide faster than men. A random COHb estimation gives a good indication of the mean COHb level of an individual. PMID:4441877
Ho, Derek; Drake, Tyler K.; Bentley, Rex C.; Valea, Fidel A.; Wax, Adam
2015-01-01
We evaluate a new hybrid algorithm for determining nuclear morphology using angle-resolved low coherence interferometry (a/LCI) measurements in ex vivo cervical tissue. The algorithm combines Mie theory based and continuous wavelet transform inverse light scattering analysis. The hybrid algorithm was validated and compared to traditional Mie theory based analysis using an ex vivo tissue data set. The hybrid algorithm achieved 100% agreement with pathology in distinguishing dysplastic and non-dysplastic biopsy sites in the pilot study. Significantly, the new algorithm performed over four times faster than traditional Mie theory based analysis. PMID:26309741
Throwing speed and accuracy in baseball and cricket players.
Freeston, Jonathan; Rooney, Kieron
2014-06-01
Throwing speed and accuracy are both critical to sports performance but cannot be optimized simultaneously. This speed-accuracy trade-off (SATO) is evident across a number of throwing groups but remains poorly understood. The goal was to describe the SATO in baseball and cricket players and determine the speed that optimizes accuracy. 20 grade-level baseball and cricket players performed 10 throws at 80% and 100% of maximal throwing speed (MTS) toward a cricket stump. Baseball players then performed a further 10 throws at 70%, 80%, 90%, and 100% of MTS toward a circular target. Baseball players threw faster with greater accuracy than cricket players at both speeds. Both groups demonstrated a significant SATO as vertical error increased with increases in speed; the trade-off was worse for cricketers than baseball players. Accuracy was optimized at 70% of MTS for baseballers. Throwing athletes should decrease speed when accuracy is critical. Cricket players could adopt baseball-training practices to improve throwing performance.
Baril, Chantal; Gascon, Viviane; Brouillette, Christel
2014-03-01
Despite the fact that since 1985 the government of Québec increased by 5.75 % on average the amount of money spent on healthcare per year, little improvement was noted. It is obvious that an optimal use of resources is essential to reduce waiting times and provide safer and faster services to patients. The use of new technology can contribute to improve the healthcare system efficiency. Our study aims to assess the impact of a medication distribution technology on 1) the performance of a health and social services center's pharmacy, 2) the performance of one care unit in a nursing home and on 3) the medication-use process safety. To measure performance we were inspired by the Lean approach. The results show that medication distribution technology is considered as an effective way to significantly detect medication errors, to allow nurses to focus more on patients and pharmacy to react more rapidly to changes in patient medications.
Gallagher, A G; Satava, R M
2002-12-01
The objective assessment of the psychomotor skills of surgeons is now a priority; however, this is a difficult task because of measurement difficulties associated with the assessment of surgery in vivo. In this study, virtual reality (VR) was used to overcome these problems. Twelve experienced (>50 minimal-access procedures), 12 inexperienced laparoscopic surgeons (<10 minimal-access procedures), and 12 laparoscopic novices participated in the study. Each subject completed 10 trials on the Minimally Invasive Surgical Trainer; Virtual Reality (MIST VR). Experienced laparoscopic surgeons performed the tasks significantly (p < 0.01) faster, with less error, more economy in the movement of instruments and the use of diathermy, and with greater consistency in performance. The standardized coefficient alpha for performance measures ranged from a = 0.89 to 0.98, showing high internal measurement consistency. Test-retest reliability ranged from r = 0.96 to r = 0.5. VR is a useful tool for evaluating the psychomotor skills needed to perform laparoscopic surgery.
Benchmarking database performance for genomic data.
Khushi, Matloob
2015-06-01
Genomic regions represent features such as gene annotations, transcription factor binding sites and epigenetic modifications. Performing various genomic operations such as identifying overlapping/non-overlapping regions or nearest gene annotations are common research needs. The data can be saved in a database system for easy management, however, there is no comprehensive database built-in algorithm at present to identify overlapping regions. Therefore I have developed a novel region-mapping (RegMap) SQL-based algorithm to perform genomic operations and have benchmarked the performance of different databases. Benchmarking identified that PostgreSQL extracts overlapping regions much faster than MySQL. Insertion and data uploads in PostgreSQL were also better, although general searching capability of both databases was almost equivalent. In addition, using the algorithm pair-wise, overlaps of >1000 datasets of transcription factor binding sites and histone marks, collected from previous publications, were reported and it was found that HNF4G significantly co-locates with cohesin subunit STAG1 (SA1).Inc. © 2015 Wiley Periodicals, Inc.
Carter, Richard T.
2017-01-01
Understandably, most locomotor analyses of bats have focused on flight mechanics and behaviors. However, we investigated nonflight locomotion in an effort to glean deeper insights into the evolutionary history of bats. We used high-speed video (300 Hz) to film and compare walking and climbing mechanics and kinematics between several species of the suborders Megachiroptera (Pteropodidae) versus Microchiroptera (Vespertilionidae and Phyllostomatidae). We found fundamentally distinctive behaviors, functional abilities, and performance outcomes between groups, but nearly homogeneous outcomes within groups. Megachiropterans exhibited climbing techniques and skills not found in microchiropterans and which aligned with other fully arboreal mammals. Megachiropterans climbed readily when placed in a head-up posture on a vertical surface, showed significantly greater ability than microchiropterans to abduct and extend the reach of their limbs, and climbed at a greater pace by using a more aggressive ipsilateral gait, at times being supported by only a single contact point. In addition, megachiropterans showed little ability to employ basic walking mechanics when placed on the ground, also a pattern observed in some highly adapted arboreal mammals. Conversely, microchiropterans resisted climbing vertical surfaces in a head-up posture, showed significantly less extension of their limbs, and employed a less-aggressive, slower contralateral gait with three points of contact. When walking, microchiropterans used the same gait they did when climbing which is representative of basic tetrapod terrestrial mechanics. Curiously, megachiropterans cycled their limbs significantly faster when climbing than when attempting to walk, whereas microchiropterans cycled their limbs at significantly faster rates when walking than when climbing. We contend that nonflight locomotion mechanics give a deep evolutionary view into the ancestral es locomotor platform on which flight was built in each of these groups. PMID:28957404
Alpha Lipoic Acid (ALA) effects on subchorionic hematoma: preliminary clinical results.
Porcaro, G; Brillo, E; Giardina, I; Di Iorio, R
2015-09-01
The clinic use of alpha Lipoic Acid (ALA) is linked to its capability to exert antioxidant effects and, more interestingly, to counteract the pathologic changes of complex networks of cytokines, chemokines and growth factors, restoring their physiological state. The aim of this randomized controlled clinical trial was to test the contribution of oral supplementation of ALA to the standard treatment with Progesterone vaginal suppositories, in healing subchorionic hematomas in patients with threatened miscarriage. Controls were administered only Progesterone suppositories. Nineteen pregnant women in the first trimester of gestation, with threatened miscarriage and ultrasound evidence of subchorionic hematoma, were included in the trial and randomly divided in two groups: controls, treated with 400 mg Progesterone (200 mg 2 times per day), given by vaginal suppositories, and case study treated with the same Progesterone dosage, plus ALA, given orally at the dose of 600 mg (300 mg 2 times per day, DAV®, Lo.Li. Pharma srl, Italy). Sixteen patients completed the trial. Treatment was performed until complete resolution of the clinical picture. In both groups, the subjects improved significantly but, in general, a better and faster evolution in the major signs of threatened miscarriage was observed in the subjects treated with ALA and Progesterone. In these patients, the speed of resorption of subchorionic hematoma was significantly (p ≤ 0.05) superior compared to controls. The ALA and Progesterone group showed a faster decrease or disappearance of all symptoms than that observed in the control group, however the difference was not significant. These preliminary results suggest that ALA supplementation significantly contributes to speed up the process of restoration of physiological conditions in threatened miscarriage and ameliorates the medical conditions of both the mothers and the foetus, probably modulating the networks of cytokines, growth factors and other molecules.
Allen, Karen; Blascovich, Jim; Mendes, Wendy B
2002-01-01
The purpose of this study was to examine the effects of the presence of friends, spouses, and pets on cardiovascular reactivity to psychological and physical stress. Cardiovascular reactivity was examined among 240 married couples, half of whom owned a pet. Mental arithmetic and cold pressor were performed in one of four randomly assigned social support conditions: alone, with pet or friend (friend present for non-pet owners), with spouse, with spouse and pet/friend. Relative to people without pets, people with pets had significantly lower heart rate and blood pressure levels during a resting baseline, significantly smaller increases (ie, reactivity) from baseline levels during the mental arithmetic and cold pressor, and faster recovery. Among pet owners, the lowest reactivity and quickest recovery was observed in the pet-present conditions. People perceive pets as important, supportive parts of their lives, and significant cardiovascular and behavioral benefits are associated with those perceptions.
Chang, Chiou Ling; Cho, Il Kyu; Li, Qing X
2009-02-01
Basil oil and its three major active constituents (trans-anethole, estragole, and linalool) obtained from basil (Oscimum basilicum L.) were tested on three tephritid fruit fly species [Ceratitis capitata (Wiedemann), Bactrocera dorsalis (Hendel), and Bactrocera cucurbitae (Coquillett)] for insecticidal activity. All test chemicals acted fast and showed a steep dose-response relationship. The lethal times for 90% mortality/knockdown (LT90) of the three fly species to 10% of the test chemicals were between 8 and 38 min. The toxic action of basil oil in C. capitata occurred significantly faster than in B. cucurbitae but slightly faster than in B. dorsalis. Estragole acted faster in B. dorsalis than in C. capitata and B. cucurbitae. Linalool action was faster in B. dorsalis and C. capitata than in B. cucurbitae. trans-Anethole action was similar to all three species. Methyl eugenol acted faster in C. capitata and B. cucurbitae than in B. dorsalis. When linalool was mixed with cuelure (attractant to B. cucurbitae male), its potency to the three fly species decreased as the concentration of cuelure increased. This was due to linalool hydrolysis catalyzed by acetic acid from cuelure degradation, which was confirmed by chemical analysis. When methyl eugenol (B. dorsalis male attractant) was mixed with basil oil, trans-anethole, estragole, or linalool, it did not affect the toxicity of basil oil and linalool to B. dorsalis, but it did significantly decrease the toxicity of trans-anethole and estragole. Structural similarity between methyl eugenol and trans-anethole and estragole suggests that methyl eugenol might act at a site similar to that of trans-anethole and estragole and serve as an antagonist if an action site exists. Methyl eugenol also may play a physiological role on the toxicity reduction.
Gerbier, Pierre; Binet, Aurélien; Etancelin, Mathilde; Barteau, Emmanuel; Auger, Marie; Morales, Luciano; Bertrand, Philippe; Sirinelli, Dominique; Morel, Baptiste
2018-04-01
The objective of this study was to evaluate the progress in performance of senior residents in diagnosing acute appendicitis. Results were collected and compared of ultrasound examinations performed for suspected acute appendicitis by three senior residents and two faculty members over a six-month period in a university hospital setting. A grid with the sonographic findings was completed separately by the residents and the faculty members immediately after each examination. The duration of each examination was reported. The final ultrasound diagnosis was compared to the surgical and pathological results and to the clinical follow-up. The residents and faculty members performed 171 consecutive ultrasound examinations including 49 children with acute appendicitis and 122 with normal appendices. The accuracy of the diagnosis by the residents was 96%, and was similar to that of the faculty members (kappa=0.90) over the six months. The duration of the resident ultrasound examinations was significantly shorter during the second three-month period (p=0.01). No significant differences in diagnostic accuracy were demonstrated by the residents between the first and second three-month periods (p=0.06). The residents performed well when using sonography to diagnose acute appendicitis in children, and were faster during the second three-month period. I. Copyright © 2017 Elsevier Inc. All rights reserved.
A faster and more reliable data acquisition system for the full performance of the SciCRT
Sasai, Y.; Matsubara, Y.; Itow, Y.; ...
2017-01-03
The SciBar Cosmic Ray Telescope (SciCRT) is a massive scintillator tracker to observe cosmic rays at a very high-altitude environment in Mexico. The fully active tracker is based on the Scintillator Bar (SciBar) detector developed as a near detector for the KEK-to-Kamioka long-baseline neutrino oscillation experiment (K2K) in Japan. Since the data acquisition (DAQ) system was developed for the accelerator experiment, we determined to develop a new robust DAQ system to optimize it to our cosmic-ray experiment needs at the top of Mt. Sierra Negra (4600 m). One of our special requirements is to achieve a 10 times faster readoutmore » rate. We started to develop a new fast readout back-end board (BEB) based on 100 Mbps SiTCP, a hardware network processor developed for DAQ systems for high energy physics experiments. Then we developed the new BEB which has a potential of 20 times faster than the current one in the case of observing neutrons. Lastly, we installed the new DAQ system including the new BEBs to a part of the SciCRT in July 2015. The system has been operating since then. In this article, we describe the development, the basic performance of the new BEB, the status after the installation in the SciCRT, and the future performance.« less
DeepFruits: A Fruit Detection System Using Deep Neural Networks
Sa, Inkyu; Ge, Zongyuan; Dayoub, Feras; Upcroft, Ben; Perez, Tristan; McCool, Chris
2016-01-01
This paper presents a novel approach to fruit detection using deep convolutional neural networks. The aim is to build an accurate, fast and reliable fruit detection system, which is a vital element of an autonomous agricultural robotic platform; it is a key element for fruit yield estimation and automated harvesting. Recent work in deep neural networks has led to the development of a state-of-the-art object detector termed Faster Region-based CNN (Faster R-CNN). We adapt this model, through transfer learning, for the task of fruit detection using imagery obtained from two modalities: colour (RGB) and Near-Infrared (NIR). Early and late fusion methods are explored for combining the multi-modal (RGB and NIR) information. This leads to a novel multi-modal Faster R-CNN model, which achieves state-of-the-art results compared to prior work with the F1 score, which takes into account both precision and recall performances improving from 0.807 to 0.838 for the detection of sweet pepper. In addition to improved accuracy, this approach is also much quicker to deploy for new fruits, as it requires bounding box annotation rather than pixel-level annotation (annotating bounding boxes is approximately an order of magnitude quicker to perform). The model is retrained to perform the detection of seven fruits, with the entire process taking four hours to annotate and train the new model per fruit. PMID:27527168
DeepFruits: A Fruit Detection System Using Deep Neural Networks.
Sa, Inkyu; Ge, Zongyuan; Dayoub, Feras; Upcroft, Ben; Perez, Tristan; McCool, Chris
2016-08-03
This paper presents a novel approach to fruit detection using deep convolutional neural networks. The aim is to build an accurate, fast and reliable fruit detection system, which is a vital element of an autonomous agricultural robotic platform; it is a key element for fruit yield estimation and automated harvesting. Recent work in deep neural networks has led to the development of a state-of-the-art object detector termed Faster Region-based CNN (Faster R-CNN). We adapt this model, through transfer learning, for the task of fruit detection using imagery obtained from two modalities: colour (RGB) and Near-Infrared (NIR). Early and late fusion methods are explored for combining the multi-modal (RGB and NIR) information. This leads to a novel multi-modal Faster R-CNN model, which achieves state-of-the-art results compared to prior work with the F1 score, which takes into account both precision and recall performances improving from 0 . 807 to 0 . 838 for the detection of sweet pepper. In addition to improved accuracy, this approach is also much quicker to deploy for new fruits, as it requires bounding box annotation rather than pixel-level annotation (annotating bounding boxes is approximately an order of magnitude quicker to perform). The model is retrained to perform the detection of seven fruits, with the entire process taking four hours to annotate and train the new model per fruit.
Gumert, Michael D; Hoong, Low Kuan; Malaivijitnond, Suchinda
2011-12-01
We investigated sex differences in how Burmese long-tailed macaques (Macaca fascicularis aurea) used stone tools to open shelled food items along the shores of two islands in Laemson National Park, Thailand. Over a 2-week period in December 2009, we collected scan and focal samples on macaques when they were visible along the shores and mangroves. We found females used stones more often while feeding and used smaller tools than males. Females also processed sessile oysters more than males, whereas males processed unattached foods more than females. It was unclear which sex was overall more proficient at stone tool use, but males did perform significantly better at opening unattached food items with large pounding stones. Females also struck food items more times during tool-use bouts and at a faster rate, but no significant difference was found in average tool-use bout duration. Males processed foods slightly faster within a tool-use bout, but we were unable to detect a significant difference in the rate of food processing while foraging with tools. In summary females chipped open sessile oysters with an axing technique more than males, while males used larger stones to pound open unattached shelled food more often than females. Despite using pounding more than females, males also regularly utilized the axing technique on sessile oysters. Our results are the first assessment of sex differences in macaque stone tool use, providing a basis for comparison with tool use in other primates, and to nonfunctional forms of stone use in other macaques. © 2011 Wiley Periodicals, Inc.
Thomas, Andrew S; Elcock, Adrian H
2006-06-21
Proteins and other biomolecules function in cellular environments that contain significant concentrations of dissolved salts and even simple salts such as NaCl can significantly affect both the kinetics and thermodynamics of macromolecular interactions. As one approach to directly observing the effects of salt on molecular associations, explicit-solvent molecular dynamics (MD) simulations have been used here to model the association of pairs of the amino acid analogues acetate and methylammonium in aqueous NaCl solutions of concentrations 0, 0.1, 0.3, 0.5, 1, and 2 M. By performing simulations of 500 ns duration for each salt concentration properly converged estimates of the free energy of interaction of the two molecules have been obtained for all intermolecular separation distances and geometries. The resulting free energy surfaces are shown to give significant new insights into the way salt modulates interactions between molecules containing both charged and hydrophobic groups and are shown to provide valuable new benchmarks for testing the description of salt effects provided by the simpler but faster Poisson-Boltzmann method. In addition, the complex many-dimensional free energy surfaces are shown to be decomposable into a number of one-dimensional effective energy functions. This decomposition (a) allows an unambiguous view of the qualitative differences between the salt dependence of electrostatic and hydrophobic interactions, (b) gives a clear rationalization for why salt exerts different effects on protein-protein association and dissociation rates, and (c) produces simplified energy functions that can be readily used in much faster Brownian dynamics simulations.
NASA Astrophysics Data System (ADS)
Chase, Patrick; Vondran, Gary
2011-01-01
Tetrahedral interpolation is commonly used to implement continuous color space conversions from sparse 3D and 4D lookup tables. We investigate the implementation and optimization of tetrahedral interpolation algorithms for GPUs, and compare to the best known CPU implementations as well as to a well known GPU-based trilinear implementation. We show that a 500 NVIDIA GTX-580 GPU is 3x faster than a 1000 Intel Core i7 980X CPU for 3D interpolation, and 9x faster for 4D interpolation. Performance-relevant GPU attributes are explored including thread scheduling, local memory characteristics, global memory hierarchy, and cache behaviors. We consider existing tetrahedral interpolation algorithms and tune based on the structure and branching capabilities of current GPUs. Global memory performance is improved by reordering and expanding the lookup table to ensure optimal access behaviors. Per multiprocessor local memory is exploited to implement optimally coalesced global memory accesses, and local memory addressing is optimized to minimize bank conflicts. We explore the impacts of lookup table density upon computation and memory access costs. Also presented are CPU-based 3D and 4D interpolators, using SSE vector operations that are faster than any previously published solution.
Influence of environmental temperature on duathlon performance.
Sparks, S A; Cable, N T; Doran, D A; Maclaren, D P M
The aim of this study was to evaluate the physiological, metabolic and performance responses to duathlon performance under a range of ambient temperatures. Ten male recreational athletes performed three self-paced duathlon time trials consisting of a 5 km run (R1), a 30 km cycle and a 5 km run (R2) at 10 degrees C, 20 degrees C and 30 degrees C and a relative humidity of 50%. Performance times, heart rate (HR), rating of perceived exertion (RPE), core temperature (Tc) and skin temperature (Tsk) were measured every kilometre. Carbohydrate and fat oxidation rates were calculated via expired gas analysis at the first and fourth kilometres during both running stages. Blood samples were taken before and after exercise for the determination of prolactin concentration.Overall performance was significantly faster at 10 degrees C (100.76+/-5.32 min) than at 30 degrees C (105.38 +/- 4.28 min). Significantly higher Tc was noted in the 30 degrees C trial than in the 10 degrees C trial, with concomitant elevations in prolactin after exercise (19.88 +/- 6.48 ng/ml at 30 degrees C; 13.10 +/- 8.75 ng/ml at 10 degrees C). The rates of carbohydrate oxidation did not differ between conditions, although fat oxidation rates were highest at 10 degrees C. Elevated ambient temperature has a negative effect on duathlon performance. This effect may be reflected in increased Tc and prolactin concentration.
DOE Office of Scientific and Technical Information (OSTI.GOV)
White, D.B.
This paper reports on experiments to examine gas migration rates in drilling muds that were performed in a 15-m-long, 200-mm-ID inclinable flow loop where air injection simulates gas entry during a kick. These tests were conducted using a xanthum gum (a common polymer used in drilling fluids) solution to simulate drilling muds as the liquid phase and air as the gas phase. This work represents a significant extension of existing correlations for gas/liquid flows in large pipe diameters with non- Newtonian fluids. Bubbles rise faster in drilling muds than in water despite the increased viscosity. This surprising result is causedmore » by the change in the flow regime, with large slug-type bubbles forming at lower void fractions. The gas velocity is independent of void fraction, thus simplifying flow modeling. Results show that a gas influx will rise faster in a well than previously believed. This has major implications for kick simulation, with gas arriving at the surface earlier than would be expected and the gas outflow rate being higher than would have been predicted. A model of the two-phase gas flow in drilling mud, including the results of this work, has been incorporated into the joint Schlumberger Cambridge Research (SCR)/BP Intl. kick model.« less
Intervertebral disc detection in X-ray images using faster R-CNN.
Ruhan Sa; Owens, William; Wiegand, Raymond; Studin, Mark; Capoferri, Donald; Barooha, Kenneth; Greaux, Alexander; Rattray, Robert; Hutton, Adam; Cintineo, John; Chaudhary, Vipin
2017-07-01
Automatic identification of specific osseous landmarks on the spinal radiograph can be used to automate calculations for correcting ligament instability and injury, which affect 75% of patients injured in motor vehicle accidents. In this work, we propose to use deep learning based object detection method as the first step towards identifying landmark points in lateral lumbar X-ray images. The significant breakthrough of deep learning technology has made it a prevailing choice for perception based applications, however, the lack of large annotated training dataset has brought challenges to utilizing the technology in medical image processing field. In this work, we propose to fine tune a deep network, Faster-RCNN, a state-of-the-art deep detection network in natural image domain, using small annotated clinical datasets. In the experiment we show that, by using only 81 lateral lumbar X-Ray training images, one can achieve much better performance compared to traditional sliding window detection method on hand crafted features. Furthermore, we fine-tuned the network using 974 training images and tested on 108 images, which achieved average precision of 0.905 with average computation time of 3 second per image, which greatly outperformed traditional methods in terms of accuracy and efficiency.
Gabbay Alves, Taís Vanessa; Silva da Costa, Russany; Aliakbarian, Bahar; Casazza, Alessandro Alberto; Perego, Patrizia; Carréra Silva Júnior, José Otávio; Ribeiro Costa, Roseane Maria; Converti, Attilio
2017-03-01
The cocoa extract (Theobroma cacao L.) has a significant amount of polyphenols (TP) with potent antioxidant activity (AA). This study aims to optimise microencapsulation of the extract of cocoa waste using chitosan and maltodextrin. Microencapsulation tests were performed according to a Box-Behnken factorial design, and the results were evaluated by response surface methodology with temperature, maltodextrin concentration (MD) and extract flowrate (EF) as independent variables, and the fraction of encapsulated TP, TP encapsulation yield, AA, yield of drying and solubility index as responses. The optimum conditions were: inlet temperature of 170 °C, MD of 5% and EF of 2.5 mL/min. HPLC analysis identified epicatechin as the major component of both the extract and microparticles. TP release was faster at pH 3.5 than in water. These results as a whole suggest that microencapsulation was successful and the final product can be used as a nutrient source for aquatic animal feed. Highlights Microencapsulation is optimised according to a factorial design of the Box-Behnken type. Epicatechin is the major component of both the extract and microcapsules. The release of polyphenols from microcapsules is faster at pH 3.5 than in water.
General Trends of Dihedral Conformational Transitions in a Globular Protein
Miao, Yinglong; Baudry, Jerome; Smith, Jeremy C.; McCammon, J. Andrew
2017-01-01
Dihedral conformational transitions are analyzed systematically in a model globular protein, cytochrome P450cam, to examine their structural and chemical dependences through combined conventional molecular dynamics (cMD), accelerated molecular dynamics (aMD) and Adaptive Biasing Force (ABF) simulations. The aMD simulations are performed at two acceleration levels, using dihedral and dual boost, respectively. In comparison with cMD, aMD samples protein dihedral transitions ~2 times faster on average using dihedral boost, and ~3.5 times faster using dual boost. In the protein backbone, significantly higher dihedral transition rates are observed in the Bend, Coil and Turn flexible regions, followed by the β bridge and β sheet, and then the helices. Moreover, protein sidechains of greater length exhibit higher transition rates on average in the aMD-enhanced sampling. Sidechains of the same length (particularly Nχ = 2) exhibit decreasing transition rates with residues when going from hydrophobic to polar, then charged and aromatic chemical types. The reduction of dihedral transition rates is found to be correlated with increasing energy barriers as identified through ABF free energy calculations. These general trends of dihedral conformational transitions provide important insights into the hierarchical dynamics and complex free energy landscapes of functional proteins. PMID:26799251
The Case for Intelligent Propulsion Control for Fast Engine Response
NASA Technical Reports Server (NTRS)
Litt, Jonathan S.; Frederick, Dean K.; Guo, Ten-Huei
2009-01-01
Damaged aircraft have occasionally had to rely solely on thrust to maneuver as a consequence of losing hydraulic power needed to operate flight control surfaces. The lack of successful landings in these cases inspired research into more effective methods of utilizing propulsion-only control. That research demonstrated that one of the major contributors to the difficulty in landing is the slow response of the engines as compared to using traditional flight control. To address this, research is being conducted into ways of making the engine more responsive under emergency conditions. This can be achieved by relaxing controller limits, adjusting schedules, and/or redesigning the regulators to increase bandwidth. Any of these methods can enable faster response at the potential expense of engine life and increased likelihood of stall. However, an example sensitivity analysis revealed a complex interaction of the limits and the difficulty in predicting the way to achieve the fastest response. The sensitivity analysis was performed on a realistic engine model, and demonstrated that significantly faster engine response can be achieved compared to standard Bill of Material control. However, the example indicates the need for an intelligent approach to controller limit adjustment in order for the potential to be fulfilled.
The simplest chronoscope II: reaction time measured by meterstick versus machine.
Montare, Alberto
2010-12-01
Visual simple reaction time (SRT) scores measured in 31 college students of both sexes by use of the simplest chronoscope methodology (meterstick SRT) were compared to scores obtained by use of an electromechanical multi-choice reaction timer (machine SRT). Four hypotheses were tested. Results indicated that the previous mean value of meterstick SRT was replicated; meterstick SRT was significantly faster than long-standing population estimates of mean SRT; and machine SRT was significantly slower than the same long-standing mean SRT estimates for the population. Also, the mean meterstick SRT of 181 msec. was significantly faster than the mean machine SRT of 294 msec. It was theorized that differential visual information processing occurred such that the dorsal visual stream subserved meterstick SRT; whereas the ventral visual stream subserved machine SRT.
Daumas, Stephanie; Sandin, Johan; Chen, Karen S.; Kobayashi, Dione; Tulloch, Jane; Martin, Stephen J.; Games, Dora; Morris, Richard G.M.
2008-01-01
Two experiments were conducted to investigate the possibility of faster forgetting by PDAPP mice (a well-established model of Alzheimer’s disease as reported by Games and colleagues in an earlier paper). Experiment 1, using mice aged 13–16 mo, confirmed the presence of a deficit in a spatial reference memory task in the water maze by hemizygous PDAPP mice relative to littermate controls. However, after overtraining to a criterion of equivalent navigational performance, a series of memory retention tests revealed faster forgetting in the PDAPP group. Very limited retraining was sufficient to reinstate good memory in both groups, indicating that their faster forgetting may be due to retrieval failure rather than trace decay. In Experiment 2, 6-mo-old PDAPP and controls were required to learn each of a series of spatial locations to criterion with their memory assessed 10 min after learning each location. No memory deficit was apparent in the PDAPP mice initially, but a deficit built up through the series of locations suggestive of increased sensitivity to interference. Faster forgetting and increased interference may each reflect a difficulty in accessing memory traces. This interpretation of one aspect of the cognitive deficit in human mutant APP mice has parallels to deficits observed in patients with Alzheimer’s disease, further supporting the validity of transgenic models of the disease. PMID:18772249
Visual and flight performance recovery after PRK or LASIK in helicopter pilots.
Van de Pol, Corina; Greig, Joanna L; Estrada, Art; Bissette, Gina M; Bower, Kraig S
2007-06-01
Refractive surgery, specifically photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK), is becoming more accepted in the military environment. Determination of the impact on visual performance in the more demanding aviation environment was the impetus for this study. A prospective evaluation of 20 Black Hawk pilots pre-surgically and at 1 wk, 1 mo, and 6 mo postsurgery was conducted to assess both PRK and LASIK visual and flight performance outcomes on the return of aviators to duty. Of 20 pilots, 19 returned to flight status at 1 mo after surgery; 1 PRK subject was delayed due to corneal haze and subjective visual symptoms. Improvements were seen under simulator night and night vision goggle flight after LASIK; no significant changes in flight performance were measured in the aircraft. Results indicated a significantly faster recovery of all visual performance outcomes 1 wk after LASIK vs. PRK, with no difference between procedures at 1 and 6 mo. Low contrast acuity and contrast sensitivity only weakly correlated to flight performance in the early post-operative period. Overall flight performance assessed in this study after PRK and LASIK was stable or improved from baseline, indicating a resilience of performance despite measured decrements in visual performance, especially in PRK. More visually demanding flight tasks may be impacted by subtle changes in visual performance. Contrast tests are more sensitive to the effects of refractive surgical intervention and may prove to be a better indicator of visual recovery for return to flight status.
Exploring What’s Missing: What Do Target Absent Trials Reveal About Autism Search Superiority?
Keehn, Brandon; Joseph, Robert M.
2016-01-01
We used eye-tracking to investigate the roles of enhanced discrimination and peripheral selection in superior visual search in autism spectrum disorder (ASD). Children with ASD were faster at visual search than their typically developing peers. However, group differences in performance and eye-movements did not vary with the level of difficulty of discrimination or selection. Rather, consistent with prior ASD research, group differences were mainly the effect of faster performance on target-absent trials. Eye-tracking revealed a lack of left-visual-field search asymmetry in ASD, which may confer an additional advantage when the target is absent. Lastly, ASD symptomatology was positively associated with search superiority, the mechanisms of which may shed light on the atypical brain organization that underlies social-communicative impairment in ASD. PMID:26762114
Montare, Alberto
2013-06-01
The three classical Donders' reaction time (RT) tasks (simple, choice, and discriminative RTs) were employed to compare reaction time scores from college students obtained by use of Montare's simplest chronoscope (meterstick) methodology to scores obtained by use of a digital-readout multi-choice reaction timer (machine). Five hypotheses were tested. Simple RT, choice RT, and discriminative RT were faster when obtained by meterstick than by machine. The meterstick method showed higher reliability than the machine method and was less variable. The meterstick method of the simplest chronoscope may help to alleviate the longstanding problems of low reliability and high variability of reaction time performances; while at the same time producing faster performance on Donders' simple, choice and discriminative RT tasks than the machine method.
Dedoncker, Josefien; Brunoni, Andre R; Baeken, Chris; Vanderhasselt, Marie-Anne
2016-01-01
Research into the effects of transcranial direct current stimulation of the dorsolateral prefrontal cortex on cognitive functioning is increasing rapidly. However, methodological heterogeneity in prefrontal tDCS research is also increasing, particularly in technical stimulation parameters that might influence tDCS effects. To systematically examine the influence of technical stimulation parameters on DLPFC-tDCS effects. We performed a systematic review and meta-analysis of tDCS studies targeting the DLPFC published from the first data available to February 2016. Only single-session, sham-controlled, within-subject studies reporting the effects of tDCS on cognition in healthy controls and neuropsychiatric patients were included. Evaluation of 61 studies showed that after single-session a-tDCS, but not c-tDCS, participants responded faster and more accurately on cognitive tasks. Sub-analyses specified that following a-tDCS, healthy subjects responded faster, while neuropsychiatric patients responded more accurately. Importantly, different stimulation parameters affected a-tDCS effects, but not c-tDCS effects, on accuracy in healthy samples vs. increased current density and density charge resulted in improved accuracy in healthy samples, most prominently in females; for neuropsychiatric patients, task performance during a-tDCS resulted in stronger increases in accuracy rates compared to task performance following a-tDCS. Healthy participants respond faster, but not more accurate on cognitive tasks after a-tDCS. However, increasing the current density and/or charge might be able to enhance response accuracy, particularly in females. In contrast, online task performance leads to greater increases in response accuracy than offline task performance in neuropsychiatric patients. Possible implications and practical recommendations are discussed. Copyright © 2016 Elsevier Inc. All rights reserved.
Experimental Procedure for Warm Spinning of Cast Aluminum Components.
Roy, Matthew J; Maijer, Daan M
2017-02-01
High performance, cast aluminum automotive wheels are increasingly being incrementally formed via flow forming/metal spinning at elevated temperatures to improve material properties. With a wide array of processing parameters which can affect both the shape attained and resulting material properties, this type of processing is notoriously difficult to commission. A simplified, light-duty version of the process has been designed and implemented for full-size automotive wheels. The apparatus is intended to assist in understanding the deformation mechanisms and the material response to this type of processing. An experimental protocol has been developed to prepare for, and subsequently perform forming trials and is described for as-cast A356 wheel blanks. The thermal profile attained, along with instrumentation details are provided. Similitude with full-scale forming operations which impart significantly more deformation at faster rates is discussed.
Experimental Procedure for Warm Spinning of Cast Aluminum Components
Roy, Matthew J.; Maijer, Daan M.
2017-01-01
High performance, cast aluminum automotive wheels are increasingly being incrementally formed via flow forming/metal spinning at elevated temperatures to improve material properties. With a wide array of processing parameters which can affect both the shape attained and resulting material properties, this type of processing is notoriously difficult to commission. A simplified, light-duty version of the process has been designed and implemented for full-size automotive wheels. The apparatus is intended to assist in understanding the deformation mechanisms and the material response to this type of processing. An experimental protocol has been developed to prepare for, and subsequently perform forming trials and is described for as-cast A356 wheel blanks. The thermal profile attained, along with instrumentation details are provided. Similitude with full-scale forming operations which impart significantly more deformation at faster rates is discussed. PMID:28190063
Multi-GPU accelerated three-dimensional FDTD method for electromagnetic simulation.
Nagaoka, Tomoaki; Watanabe, Soichi
2011-01-01
Numerical simulation with a numerical human model using the finite-difference time domain (FDTD) method has recently been performed in a number of fields in biomedical engineering. To improve the method's calculation speed and realize large-scale computing with the numerical human model, we adapt three-dimensional FDTD code to a multi-GPU environment using Compute Unified Device Architecture (CUDA). In this study, we used NVIDIA Tesla C2070 as GPGPU boards. The performance of multi-GPU is evaluated in comparison with that of a single GPU and vector supercomputer. The calculation speed with four GPUs was approximately 3.5 times faster than with a single GPU, and was slightly (approx. 1.3 times) slower than with the supercomputer. Calculation speed of the three-dimensional FDTD method using GPUs can significantly improve with an expanding number of GPUs.
Rahman, Ziyaur; Korang-Yeboah, Maxwell; Siddiqui, Akhtar; Mohammad, Adil; Khan, Mansoor A
2015-11-10
Warfarin sodium (WS) is a narrow therapeutic index drug and its product quality should be thoroughly understood and monitored in order to avoid clinical performance issues. This study was focused on understanding the effect of manufacturing and formulation variables on WS product critical quality attributes (CQAs). Eight formulations were developed with lactose monohydrate (LM) or lactose anhydrous (LA), and were either wet granulated or directly compressed. Formulations were granulated either with ethanol, isopropyl alcohol (IPA) and IPA-water mixture (50:50). Formulations were characterized for IPA, water content, hardness, disintegration time (DT), assay, dissolution and drug physical forms (scanning electron microscopy (SEM), near infrared chemical imaging (NIR-CI), X-ray powder diffraction (XRPD) and solid state nuclear magnetic resonance (ssNMR)), and performed accelerated stability studies at 40°C/75% RH for three days. The DT and dissolution of directly compressed formulations were faster than wet granulated formulations. This was due to phase transformation of crystalline drug into its amorphous form as indicated by SEM, NIR-CI, XRPD and ssNMR data which itself act as a binder. Similarly, LM showed faster disintegration and dissolution than LA containing formulations. Stability results indicated an increase in hardness and DT, and a decrease in dissolution rate and extent. This was due to phase transformation of the drug and consolidation with particles' bonding. In conclusion, the CQAs of WS product were significantly affected by manufacturing and formulation variables. Published by Elsevier B.V.
Sarmiento, M; Ramírez, P; Parody, R; Salas, M Q; Beffermann, N; Jara, V; Bertín, P; Pizarro, I; Lorca, C; Rivera, E; Galleguillos, M; Ocqueteau, M; Sánchez-Ortega, I; Patiño, B; Sureda, A
2018-02-13
Autologous stem cell transplantation (auto-HSCT) is an effective treatment strategy for hematological malignancies. The standard mode of handling hematopoietic progenitors for the autologous procedure (CRYO) consists on its collection and freezing with dimethyl sulfoxide (DMSO) and its subsequent thawing and re-infusion. This process is toxic and expensive. Non-cryopreserved (non-CRYO) is a less expensive mode of auto-HSCT. We designed a comparative study between both strategies performed in two different centers to analyze the short-term complications. In total 111 auto-HSCT were performed from January/2015 to October/2016 (42 non-CRYO and 74 CRYO). There were 74 males and 69 (62%) patients had the underlying diagnosis of multiple myeloma. No differences were seen on the characteristics of the apheresis products and their viability. Engraftment was significantly faster in the non-CRYO group (p = 0.001). Febrile neutropenia and severe mucositis were lower in the non-CRYO group (40% vs 92% p = 0.0001 and 11% vs 64%, p = 0.001, respectively). In addition, length of hospitalization was 5 days shorter in the non-CRYO group (p = 0.0001). Overall responses and transplantation outcomes were similar. Our data demonstrate a clear advantage of the non-CRYO over CRYO auto-HSCT with faster engraftment, lower incidence of febrile neutropenia and shorter hospital stay after the transplantation procedure. These data are especially relevant for centers with high transplant activity or with limited resources.
The Influence of Temporal Resolution Power and Working Memory Capacity on Psychometric Intelligence
ERIC Educational Resources Information Center
Troche, Stefan J.; Rammsayer, Thomas H.
2009-01-01
According to the temporal resolution power (TRP) hypothesis, higher TRP as reflected by better performance on psychophysical timing tasks accounts for faster speed of information processing and increased efficiency of information processing leading to better performance on tests of psychometric intelligence. An alternative explanation of…
Srivastava, Sunil; Patil, Aditya Nanasaheb; Prakash, Chaitra; Kumari, Hiranmayi
2017-01-01
Objective: Despite the myriad options available, there is no universally accepted treatment for keloids. Our objective was to compare three regimens and establish superiority in terms of objective and subjective outcomes. Approach: In this randomized parallel group study, 60 patients were enrolled and randomly allocated to three groups. Patients received intralesional injections of triamcinolone acetonide (TAC) in Group TAC, 5-fluorouracil (5FU) in Group 5FU, and a combination in Group T + F every 3 weeks till 24 weeks or till the keloid resolved. Results: There was a reduction in all parameters at every successive assessment in all three groups. Improvement in terms of height, vascularity, and pliability was fastest with 5FU, TAC, and T + F group, respectively, which was statistically significant. Decrease in pigmentation was significantly faster with T+F. Reduction in pruritus, however, was significantly faster with 5FU than the other groups, but the difference in reduction of pain among the three groups was not significant. Telangiectasias and skin atrophy were seen most commonly in TAC group, while skin ulceration was a common problem in 5FU group. Conclusion: TAC, 5FU, and their combination are all effective in keloid scars. A combination of TAC +5FU seems to offer the balanced benefit of faster and more efficacious response with lesser adverse effects when compared to individual drugs. PMID:29098115
Auditory and visual interhemispheric communication in musicians and non-musicians.
Woelfle, Rebecca; Grahn, Jessica A
2013-01-01
The corpus callosum (CC) is a brain structure composed of axon fibres linking the right and left hemispheres. Musical training is associated with larger midsagittal cross-sectional area of the CC, suggesting that interhemispheric communication may be faster in musicians. Here we compared interhemispheric transmission times (ITTs) for musicians and non-musicians. ITT was measured by comparing simple reaction times to stimuli presented to the same hemisphere that controlled a button-press response (uncrossed reaction time), or to the contralateral hemisphere (crossed reaction time). Both visual and auditory stimuli were tested. We predicted that the crossed-uncrossed difference (CUD) for musicians would be smaller than for non-musicians as a result of faster interhemispheric transfer times. We did not expect a difference in CUDs between the visual and auditory modalities for either musicians or non-musicians, as previous work indicates that interhemispheric transfer may happen through the genu of the CC, which contains motor fibres rather than sensory fibres. There were no significant differences in CUDs between musicians and non-musicians. However, auditory CUDs were significantly smaller than visual CUDs. Although this auditory-visual difference was larger in musicians than non-musicians, the interaction between modality and musical training was not significant. Therefore, although musical training does not significantly affect ITT, the crossing of auditory information between hemispheres appears to be faster than visual information, perhaps because subcortical pathways play a greater role for auditory interhemispheric transfer.
The Simplest Chronoscope V: A Theory of Dual Primary and Secondary Reaction Time Systems.
Montare, Alberto
2016-12-01
Extending work by Montare, visual simple reaction time, choice reaction time, discriminative reaction time, and overall reaction time scores obtained from college students by the simplest chronoscope (a falling meterstick) method were significantly faster as well as significantly less variable than scores of the same individuals from electromechanical reaction timers (machine method). Results supported the existence of dual reaction time systems: an ancient primary reaction time system theoretically activating the V5 parietal area of the dorsal visual stream that evolved to process significantly faster sensory-motor reactions to sudden stimulations arising from environmental objects in motion, and a secondary reaction time system theoretically activating the V4 temporal area of the ventral visual stream that subsequently evolved to process significantly slower sensory-perceptual-motor reactions to sudden stimulations arising from motionless colored objects. © The Author(s) 2016.
Dielectric Properties of Poly(ethylene oxide) from Molecular Dynamics Simulations
NASA Technical Reports Server (NTRS)
Smith, Grant D.
1994-01-01
The order, conformations and dynamics of poly(oxyethylene) (POE) melts have been investigated through molecular dynamics simulations. The potential energy functions were determined from detailed ab initio electronic structure calculations of the conformational energies of the model molecules 1,2-dimethoxyethane (DME) and diethylether. The x-ray structure factor for POE from simulation will be compared to experiment. In terms of conformation, simulations reveal that chains are extended in the melt relative to isolated chains due to the presence of strong intermolecular O...H interactions, which occur at the expense of intramolecular O...H interactions. Conformational dynamics about the C-C bond were found to be significantly faster than in polymethylene, while conformational dynamics about the C-O bond even faster than the C-C dynamics. The faster local dynamics in POE relative to polymethylene is consistent with C-13 NMR spin-lattice relaxation experiments. Conformational transitions showed significant second-neighbor correlation, as was found for polymethylene. This correlation of transitions with C-C neighbors was found to be reduced relative to C-O neighbors. Dielectric relaxation from simulation will also be compared with experiment.
Oyana, Tonny J; Achenie, Luke E K; Heo, Joon
2012-01-01
The objective of this paper is to introduce an efficient algorithm, namely, the mathematically improved learning-self organizing map (MIL-SOM) algorithm, which speeds up the self-organizing map (SOM) training process. In the proposed MIL-SOM algorithm, the weights of Kohonen's SOM are based on the proportional-integral-derivative (PID) controller. Thus, in a typical SOM learning setting, this improvement translates to faster convergence. The basic idea is primarily motivated by the urgent need to develop algorithms with the competence to converge faster and more efficiently than conventional techniques. The MIL-SOM algorithm is tested on four training geographic datasets representing biomedical and disease informatics application domains. Experimental results show that the MIL-SOM algorithm provides a competitive, better updating procedure and performance, good robustness, and it runs faster than Kohonen's SOM.
Beyond the faster-is-slower effect
NASA Astrophysics Data System (ADS)
Sticco, I. M.; Cornes, F. E.; Frank, G. A.; Dorso, C. O.
2017-11-01
The "faster-is-slower" effect arises when crowded people push each other to escape through an exit during an emergency situation. As individuals push harder, a statistical slowing down in the evacuation time can be achieved. The slowing down is caused by the presence of small groups of pedestrians (say, a small human cluster) that temporarily block the way out when trying to leave the room. The pressure on the pedestrians belonging to this blocking cluster increases for increasing anxiety levels and/or a larger number of individuals trying to leave the room through the same door. Our investigation shows, however, that very high pressures alter the dynamics in the blocking cluster and, thus, change the statistics of the time delays along the escaping process. A reduction in the long lasting delays can be acknowledged, while the overall evacuation performance improves. We present results on this phenomenon taking place beyond the faster-is-slower regime.
Korten, Nicole C M; Penninx, Brenda W J H; Pot, Anne Margriet; Deeg, Dorly J H; Comijs, Hannie C
2014-06-01
To examine whether persons who experienced adverse childhood events or recent negative life events have a worse cognitive performance and faster cognitive decline and the role of depression and apolipoprotein E-∊4 in this relationship. The community-based sample consisted of 10-year follow-up data of 1312 persons participating in the Longitudinal Aging Study Amsterdam (age range 65-85 years). Persons who experienced adverse childhood events showed a faster 10-year decline in processing speed but only when depressive symptoms were experienced. Persons with more recent negative life events showed slower processing speed at baseline but no faster decline. Childhood adversity may cause biological or psychological vulnerability, which is associated with both depressive symptoms and cognitive decline in later life. The accumulation of recent negative life events did not affect cognitive functioning over a longer time period. © The Author(s) 2014.
Oyana, Tonny J.; Achenie, Luke E. K.; Heo, Joon
2012-01-01
The objective of this paper is to introduce an efficient algorithm, namely, the mathematically improved learning-self organizing map (MIL-SOM) algorithm, which speeds up the self-organizing map (SOM) training process. In the proposed MIL-SOM algorithm, the weights of Kohonen's SOM are based on the proportional-integral-derivative (PID) controller. Thus, in a typical SOM learning setting, this improvement translates to faster convergence. The basic idea is primarily motivated by the urgent need to develop algorithms with the competence to converge faster and more efficiently than conventional techniques. The MIL-SOM algorithm is tested on four training geographic datasets representing biomedical and disease informatics application domains. Experimental results show that the MIL-SOM algorithm provides a competitive, better updating procedure and performance, good robustness, and it runs faster than Kohonen's SOM. PMID:22481977
Mujika, I; Padilla, S; Pyne, D
2002-11-01
The purpose of this study was to determine the magnitude of the swimming performance change during the final 3 weeks of training (F3T) leading to the Sydney 2000 Olympic Games. Olympic swimmers who took part in the same event or events at the Telstra 2000 Grand Prix Series in Melbourne, Australia, (26 - 27 August 2000), and 21 - 28 d later at the Sydney 2000 Olympic Games (16 - 23 September 2000) were included in this analysis. A total of 99 performances (50 male, 49 female) were analysed. The overall performance improvement between pre- and post-F3T conditions for all swimmers was 2.18 +/- 1.50 % (p < 0.0001), (range - 1.14 % to 6.02 %). A total of 91 of the 99 analysed performances were faster after the F3T and only 8 were slower. The percentage improvement with F3T was significantly higher (P < 0.01) in males (2.57 +/- 1.45 %) than in females (1.78 +/- 1.45 %). In conclusion, the pre-Olympic F3T elicited a significant performance improvement of 2.57 % for male and 1.78 % for female swimmers at the Sydney 2000 Olympic Games. The magnitude was similar for all competition events, and was achieved by swimmers from different countries and performance levels. These data provide a quantitative framework for coaches and swimmers to set realistic performance goals based on individual performance levels before the final training phase leading to important competitions.
Thermal performance curves under daily thermal fluctuation: A study in helmeted water toad tadpoles.
Bartheld, José L; Artacho, Paulina; Bacigalupe, Leonardo
2017-12-01
Most research in physiological ecology has focused on the effects of mean changes in temperature under the classic "hot vs cold" acclimation treatment; however, current evidence suggests that an increment in both the mean and variance of temperature could act synergistically to amplify the negative effects of global temperature increase and how it would affect fitness and performance-related traits in ectothermic organisms. We assessed the effects of acclimation to daily variance of temperature on thermal performance curves of swimming speed in helmeted water toad tadpoles (Calyptocephalella gayi). Acclimation treatments were 20°C ± 0.1 SD (constant) and 20°C ± 1.5 SD (fluctuating). We draw two key findings: first, tadpoles exposed to daily temperature fluctuation had reduced maximal performance (Z max ), and flattened thermal performance curves, thus supporting the "vertical shift or faster-slower" hypothesis, and suggesting that overall swimming performance would be lower through an examination of temperatures under more realistic and ecologically-relevant fluctuating regimens; second, there was significant interindividual variation in performance traits by means of significant repeatability estimates. Our present results suggest that the widespread use of constant acclimation temperatures in laboratory experiments to estimate thermal performance curves (TPCs) may lead to an overestimation of actual organismal performance. We encourage the use of temperature fluctuation acclimation treatments to better understand the variability of physiological traits, which predict ecological and evolutionary responses to global change. Copyright © 2017 Elsevier Ltd. All rights reserved.
Vorster, Martin; van der Vyver, Peet J; Paleker, Farzana
2018-05-01
The aim of this study was to compare the glide path preparation times of stainless steel hand files, PathFiles (Dentsply Sirona, Ballaigues, Switzerland), and the WaveOne Gold Glider (Dentsply Sirona). The preparation times for final root canal shaping with the Primary WaveOne Gold instrument in extracted human molar teeth with and without prior glide path preparation were also recorded and compared. Mesiobuccal canals of 60 extracted human mandibular molars (curvature angles between 25° and 35° and radii <10 mm) were selected and randomly divided into 4 groups with 15 canals each. Canals were negotiated to patency with a #8 K-file. Canal preparations were performed by a single operator using precurved #10-15-20 stainless steel manual K-files (the K-file group), a #10 stainless steel manual K-file followed by PathFiles #1-3 (the PathFile group), a #10 stainless steel manual K-file followed by WaveOne Gold Glider (the WaveOne Gold Glider group), or no further glide path preparation. Final canal preparation of all 60 canals was performed with the Primary WaveOne Gold instrument. Glide path and final preparation times were recorded. Glide path enlargement was statistically significantly fastest in the WaveOne Gold Glider group (19.7 ± 5.6 seconds) followed by the PathFile group (41.0 ± 6.8 seconds) and then the K-file group (81.2 ± 26.3 seconds) using analysis of variance (ANOVA) and Kruskal-Wallis tests (P < .0001). No statistically significant difference in the mean final preparation times was found among the WaveOne Gold Glider (23.1 ± 6.0 seconds), PathFile (24.4 ± 4.9 seconds), and K-file groups (27.2 ± 9.5 seconds). All 3 groups were statistically significantly faster than the no glide path preparation group (35.4 ± 10.2 seconds) using ANOVA (P = .0004) and Kruskal-Wallis tests (P = .0010). Preparation time with the Primary WaveOne Gold file was statistically significantly reduced when the file was used in combination with any of the glide path preparation techniques. The WaveOne Gold Glider performed statistically significantly faster in glide path preparation time than the other glide path preparation techniques. Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.
How should I regulate my emotions if I want to run faster?
Lane, Andrew M; Devonport, Tracey J; Friesen, Andrew P; Beedie, Christopher J; Fullerton, Christopher L; Stanley, Damian M
2016-01-01
The present study investigated the effects of emotion regulation strategies on self-reported emotions and 1600 m track running performance. In stage 1 of a three-stage study, participants (N = 15) reported emotional states associated with best, worst and ideal performance. Results indicated that a best and ideal emotional state for performance composed of feeling happy, calm, energetic and moderately anxious whereas the worst emotional state for performance composed of feeling downhearted, sluggish and highly anxious. In stage 2, emotion regulation interventions were developed using online material and supported by electronic feedback. One intervention motivated participants to increase the intensity of unpleasant emotions (e.g. feel more angry and anxious). A second intervention motivated participants to reduce the intensity of unpleasant emotions (e.g. feel less angry and anxious). In stage 3, using a repeated measures design, participants used each intervention before running a 1600 m time trial. Data were compared with a no treatment control condition. The intervention designed to increase the intensity of unpleasant emotions resulted in higher anxiety and lower calmness scores but no significant effects on 1600 m running time. The intervention designed to reduce the intensity of unpleasant emotions was associated with significantly slower times for the first 400 m. We suggest future research should investigate emotion regulation, emotion and performance using quasi-experimental methods with performance measures that are meaningful to participants.
Effects of preparation time and trial type probability on performance of anti- and pro-saccades.
Pierce, Jordan E; McDowell, Jennifer E
2016-02-01
Cognitive control optimizes responses to relevant task conditions by balancing bottom-up stimulus processing with top-down goal pursuit. It can be investigated using the ocular motor system by contrasting basic prosaccades (look toward a stimulus) with complex antisaccades (look away from a stimulus). Furthermore, the amount of time allotted between trials, the need to switch task sets, and the time allowed to prepare for an upcoming saccade all impact performance. In this study the relative probabilities of anti- and pro-saccades were manipulated across five blocks of interleaved trials, while the inter-trial interval and trial type cue duration were varied across subjects. Results indicated that inter-trial interval had no significant effect on error rates or reaction times (RTs), while a shorter trial type cue led to more antisaccade errors and faster overall RTs. Responses following a shorter cue duration also showed a stronger effect of trial type probability, with more antisaccade errors in blocks with a low antisaccade probability and slower RTs for each saccade task when its trial type was unlikely. A longer cue duration yielded fewer errors and slower RTs, with a larger switch cost for errors compared to a short cue duration. Findings demonstrated that when the trial type cue duration was shorter, visual motor responsiveness was faster and subjects relied upon the implicit trial probability context to improve performance. When the cue duration was longer, increased fixation-related activity may have delayed saccade motor preparation and slowed responses, guiding subjects to respond in a controlled manner regardless of trial type probability. Copyright © 2016 Elsevier B.V. All rights reserved.
Stauder, Udo; Enginee, Diplom; Elton, Hina; Penfornis, Alfred; Edelman, Steve
2014-01-01
Glucagon-like peptide-1 (GLP-1) receptor agonists are a relatively recent addition to the treatment options for type 2 diabetes mellitus (T2DM) and are administered using prefilled pen devices. In this open-label task and interview-based pilot study, 3 GLP-1 receptor agonist pen devices-exenatide (Byetta ® , Bristol-Myers Squibb/AstraZeneca), liraglutide (Victoza ® , Novo Nordisk), and lixisenatide (Lyxumia ® , Sanofi-Aventis)-were comparatively assessed in a randomized order in 30 participants with T2DM for ease of use, using a series of key performance measures (time taken to complete a series of tasks, number of user errors [successful performance], and user satisfaction rating). Linear and logistic regression analysis was conducted for the lixisenatide and liraglutide pens versus the exenatide pen. Participants' mean age was 60 years; 27% and 20% of the participants had visual impairments and reduced manual dexterity, respectively. Tasks were completed faster (P < .001) and with higher successful performance (P = .001) with the lixisenatide pen than with the exenatide pen, whereas the liraglutide pen was not statistically significant versus the exenatide pen on these parameters. Overall, user satisfaction was statistically higher for the lixisenatide and liraglutide pens versus the exenatide pen (P < .001 for both). Lixisenatide and liraglutide pens are associated with higher user satisfaction compared with the exenatide pen. In addition, the lixisenatide pen is faster and results in fewer errors than its comparator (exenatide). The lixisenatide pen may therefore be a suitable choice for patients with T2DM, including older and pen device-naïve patients, and those with visual impairments and reduced manual dexterity. © 2014 Diabetes Technology Society.
Coughlin, David J; Shiels, Lisa P; Nuthakki, Seshuvardhan; Shuman, Jacie L
2016-06-01
Rainbow smelt (Osmerus mordax), a eurythermal fish, live in environments from -1.8 to 20°C, with some populations facing substantial annual variation in environmental temperature. These different temperature regimes pose distinct challenges to locomotion by smelt. Steady swimming performance, red muscle function and muscle myosin content were examined to assess the prediction that cold acclimation by smelt will lead to improved steady swimming performance and that any performance shift will be associated with changes in red muscle function and in its myosin heavy chain composition. Cold acclimated (4°C) smelt had a faster maximum steady swimming speed and swam with a higher tailbeat frequency than warm acclimated (10°C) smelt when tested at the same temperature (10°C). Muscle mechanics experiments demonstrated faster contractile properties in the cold acclimated fish when tested at 10°C. The red muscle of cold acclimated smelt had a shorter twitch times, a shorter relaxation times and a higher maximum shortening velocity. In addition, red muscle from cold acclimated fish displayed reduced thermal sensitivity to cold, maintaining higher force levels at 4°C compared to red muscle from warm acclimated fish. Immunohistochemistry suggests shifts in muscle myosin composition and a decrease in muscle cross-sectional area with cold acclimation. Dot blot analysis confirmed a shift in myosin content. Rainbow smelt do show a significant thermal acclimation response to cold. An examination of published values of maximum muscle shortening velocity in fishes suggests that smelt are particularly well suited to high levels of activity in very cold water. Copyright © 2016 Elsevier Inc. All rights reserved.
Experimental evaluation of the certification-trail method
NASA Technical Reports Server (NTRS)
Sullivan, Gregory F.; Wilson, Dwight S.; Masson, Gerald M.; Itoh, Mamoru; Smith, Warren W.; Kay, Jonathan S.
1993-01-01
Certification trails are a recently introduced and promising approach to fault-detection and fault-tolerance. A comprehensive attempt to assess experimentally the performance and overall value of the method is reported. The method is applied to algorithms for the following problems: huffman tree, shortest path, minimum spanning tree, sorting, and convex hull. Our results reveal many cases in which an approach using certification-trails allows for significantly faster overall program execution time than a basic time redundancy-approach. Algorithms for the answer-validation problem for abstract data types were also examined. This kind of problem provides a basis for applying the certification-trail method to wide classes of algorithms. Answer-validation solutions for two types of priority queues were implemented and analyzed. In both cases, the algorithm which performs answer-validation is substantially faster than the original algorithm for computing the answer. Next, a probabilistic model and analysis which enables comparison between the certification-trail method and the time-redundancy approach were presented. The analysis reveals some substantial and sometimes surprising advantages for ther certification-trail method. Finally, the work our group performed on the design and implementation of fault injection testbeds for experimental analysis of the certification trail technique is discussed. This work employs two distinct methodologies, software fault injection (modification of instruction, data, and stack segments of programs on a Sun Sparcstation ELC and on an IBM 386 PC) and hardware fault injection (control, address, and data lines of a Motorola MC68000-based target system pulsed at logical zero/one values). Our results indicate the viability of the certification trail technique. It is also believed that the tools developed provide a solid base for additional exploration.
Sánchez-Gómez, Serafín; Herrero-Salado, Tomás F; Maza-Solano, Juan M; Ropero-Romero, Francisco; González-García, Jaime; Ambrosiani-Fernández, Jesús
2015-01-01
The high variability of sinonasal anatomy requires the best knowledge of its three-dimensional (3D) conformation to perform surgery more safely and efficiently. The aim of the study was to validate the utility of Osirix® and stereolithography in improving endoscopic sinonasal surgery planning. Osirix® was used as a viewer and Digital Imaging and Communications in Medicine (DICOM) 3D imaging manager to improve planning for 114 sinonasal endoscopic operations with polyposis (86) and chronic rhinosinusitis (CRS) (28). Stereolithography rapid prototyping was used for 7 frontoethmoidal mucoceles. Using Osirix® and stereolithography, a greater number of anatomical structures were identified and this was done faster, with a statistically-significant clinical-radiological correlation (P<.01) compared with 2D CT plates. With a share of more than 75% of surgery performed by residents, surgical time was reduced by 38±12.3min in CRS and 42±27.9 in sinonasal polyposis. The fourth-year residents reached 100% surgical competence in critical surgical milestones with 16 surgeries (CI 12-19). The systematic use of Osirix® for visualisation and treatment of 3D sinonasal images from DICOM data files, along with the surgical team's ability to manipulate them as virtual reality, allows surgeons to perform endoscopic sinonasal surgery with greater confidence and in less time than using 2D images. Residents also achieve surgical competence faster, more safely and with fewer complications. This beneficial impact is increased when the surgical team has stereolithography rapid prototyping in more complex cases. Copyright © 2014 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Patología Cérvico-Facial. All rights reserved.
Comparative Assessment of Lixisenatide, Exenatide, and Liraglutide Pen Devices
Enginee, Diplom; Elton, Hina; Penfornis, Alfred; Edelman, Steve
2014-01-01
Background: Glucagon-like peptide-1 (GLP-1) receptor agonists are a relatively recent addition to the treatment options for type 2 diabetes mellitus (T2DM) and are administered using prefilled pen devices. Method: In this open-label task and interview-based pilot study, 3 GLP-1 receptor agonist pen devices—exenatide (Byetta®, Bristol-Myers Squibb/AstraZeneca), liraglutide (Victoza®, Novo Nordisk), and lixisenatide (Lyxumia®, Sanofi-Aventis)—were comparatively assessed in a randomized order in 30 participants with T2DM for ease of use, using a series of key performance measures (time taken to complete a series of tasks, number of user errors [successful performance], and user satisfaction rating). Linear and logistic regression analysis was conducted for the lixisenatide and liraglutide pens versus the exenatide pen. Participants’ mean age was 60 years; 27% and 20% of the participants had visual impairments and reduced manual dexterity, respectively. Results: Tasks were completed faster (P < .001) and with higher successful performance (P = .001) with the lixisenatide pen than with the exenatide pen, whereas the liraglutide pen was not statistically significant versus the exenatide pen on these parameters. Overall, user satisfaction was statistically higher for the lixisenatide and liraglutide pens versus the exenatide pen (P < .001 for both). Conclusions: Lixisenatide and liraglutide pens are associated with higher user satisfaction compared with the exenatide pen. In addition, the lixisenatide pen is faster and results in fewer errors than its comparator (exenatide). The lixisenatide pen may therefore be a suitable choice for patients with T2DM, including older and pen device-naïve patients, and those with visual impairments and reduced manual dexterity. PMID:24876548
Longitudinal changes in speech recognition in older persons.
Dubno, Judy R; Lee, Fu-Shing; Matthews, Lois J; Ahlstrom, Jayne B; Horwitz, Amy R; Mills, John H
2008-01-01
Recognition of isolated monosyllabic words in quiet and recognition of key words in low- and high-context sentences in babble were measured in a large sample of older persons enrolled in a longitudinal study of age-related hearing loss. Repeated measures were obtained yearly or every 2 to 3 years. To control for concurrent changes in pure-tone thresholds and speech levels, speech-recognition scores were adjusted using an importance-weighted speech-audibility metric (AI). Linear-regression slope estimated the rate of change in adjusted speech-recognition scores. Recognition of words in quiet declined significantly faster with age than predicted by declines in speech audibility. As subjects aged, observed scores deviated increasingly from AI-predicted scores, but this effect did not accelerate with age. Rate of decline in word recognition was significantly faster for females than males and for females with high serum progesterone levels, whereas noise history had no effect. Rate of decline did not accelerate with age but increased with degree of hearing loss, suggesting that with more severe injury to the auditory system, impairments to auditory function other than reduced audibility resulted in faster declines in word recognition as subjects aged. Recognition of key words in low- and high-context sentences in babble did not decline significantly with age.
Donovan, Oliver O; Cheung, Jeanette; Catley, Maria; McGregor, Alison H; Strutton, Paul H
2006-01-01
The purpose of this study was to investigate trunk and knee strength in practitioners of hard-style martial arts. An additional objective was to examine reaction times in these participants by measuring simple reaction times (SRT), choice reaction times (CRT) and movement times (MT). Thirteen high-level martial artists and twelve sedentary participants were tested under isokinetic and isometric conditions on an isokinetic dynamometer. Response and movement times were also measured in response to simple and choice auditory cues. Results indicated that the martial arts group generated a greater body-weight adjusted peak torque with both legs at all speeds during isokinetic extension and flexion, and in isometric extension but not flexion. In isokinetic and isometric trunk flexion and extension, martial artists tended to have higher peak torques than controls, but they were not significantly different (p > 0.05). During the SRT and CRT tasks the martial artists were no quicker in lifting their hand off a button in response to the stimulus [reaction time (RT)] but were significantly faster in moving to press another button [movement time (MT)]. In conclusion, the results reveal that training in a martial art increases the strength of both the flexors and extensors of the leg. Furthermore, they have faster movement times to auditory stimuli. These results are consistent with the physical aspects of the martial arts. Key PointsMartial artists undertaking hard-style martial arts have greater strength in their knee flexor and extensor muscles as tested under isokinetic testing. Under isometric testing conditions they have stronger knee extensors only.The trunk musculature is generally higher under both conditions of testing in the martial artists, although not significantly.The total reaction times of the martial artists to an auditory stimulus were significantly faster than the control participants. When analysed further it was revealed that the decrease in reaction time was due to the movement time component of the total reaction time.The training involved for the practice of the hard-style martial arts increases the strength of muscles involved in kicking. This increased strength is not seen in the trunk muscles. Furthermore, martial artists have a faster response time; the cause of which appears to be only the faster movement time.
Donovan, Oliver O; Cheung, Jeanette; Catley, Maria; McGregor, Alison H.; Strutton, Paul H.
2006-01-01
The purpose of this study was to investigate trunk and knee strength in practitioners of hard-style martial arts. An additional objective was to examine reaction times in these participants by measuring simple reaction times (SRT), choice reaction times (CRT) and movement times (MT). Thirteen high-level martial artists and twelve sedentary participants were tested under isokinetic and isometric conditions on an isokinetic dynamometer. Response and movement times were also measured in response to simple and choice auditory cues. Results indicated that the martial arts group generated a greater body-weight adjusted peak torque with both legs at all speeds during isokinetic extension and flexion, and in isometric extension but not flexion. In isokinetic and isometric trunk flexion and extension, martial artists tended to have higher peak torques than controls, but they were not significantly different (p > 0.05). During the SRT and CRT tasks the martial artists were no quicker in lifting their hand off a button in response to the stimulus [reaction time (RT)] but were significantly faster in moving to press another button [movement time (MT)]. In conclusion, the results reveal that training in a martial art increases the strength of both the flexors and extensors of the leg. Furthermore, they have faster movement times to auditory stimuli. These results are consistent with the physical aspects of the martial arts. Key Points Martial artists undertaking hard-style martial arts have greater strength in their knee flexor and extensor muscles as tested under isokinetic testing. Under isometric testing conditions they have stronger knee extensors only. The trunk musculature is generally higher under both conditions of testing in the martial artists, although not significantly. The total reaction times of the martial artists to an auditory stimulus were significantly faster than the control participants. When analysed further it was revealed that the decrease in reaction time was due to the movement time component of the total reaction time. The training involved for the practice of the hard-style martial arts increases the strength of muscles involved in kicking. This increased strength is not seen in the trunk muscles. Furthermore, martial artists have a faster response time; the cause of which appears to be only the faster movement time. PMID:24376366
Energetics and biomechanics of locomotion by red kangaroos (Macropus rufus).
Kram, R; Dawson, T J
1998-05-01
As red kangaroos hop faster over level ground, their rate of oxygen consumption (indicating metabolic energy consumption) remains nearly the same. This phenomenon has been attributed to exceptional elastic energy storage and recovery via long compliant tendons in the legs. Alternatively, red kangaroos may have exceptionally efficient muscles. To estimate efficiency, we measured the metabolic cost of uphill hopping, where muscle fibers must perform mechanical work against gravity. We found that uphill hopping was much more expensive than level hopping. The maximal rate of oxygen consumption measured (3 ml O2 kg-1 s-1) exceeds all but a few vertebrate species. However, efficiency values were normal, approximately 30%. At faster level hopping speeds the effective mechanical advantage of the extensor muscles of the ankle joint remained the same. Thus, kangaroos generate the same muscular force at all speeds but do so more rapidly at faster hopping speeds. This contradicts a recent hypothesis for what sets the cost of locomotion. The cost of transport (J kg-1 m-1) decreases at faster hopping speeds, yet red kangaroos prefer to use relatively slow speeds that avoid high levels of tendon stress.
Hout, Michael C.; Goldinger, Stephen D.
2011-01-01
When observers search for a target object, they incidentally learn the identities and locations of “background” objects in the same display. This learning can facilitate search performance, eliciting faster reaction times for repeated displays (Hout & Goldinger, 2010). Despite these findings, visual search has been successfully modeled using architectures that maintain no history of attentional deployments; they are amnesic (e.g., Guided Search Theory; Wolfe, 2007). In the current study, we asked two questions: 1) under what conditions does such incidental learning occur? And 2) what does viewing behavior reveal about the efficiency of attentional deployments over time? In two experiments, we tracked eye movements during repeated visual search, and we tested incidental memory for repeated non-target objects. Across conditions, the consistency of search sets and spatial layouts were manipulated to assess their respective contributions to learning. Using viewing behavior, we contrasted three potential accounts for faster searching with experience. The results indicate that learning does not result in faster object identification or greater search efficiency. Instead, familiar search arrays appear to allow faster resolution of search decisions, whether targets are present or absent. PMID:21574743
Avila, Irene; Lin, Shih-Chieh
2014-03-01
The survival of animals depends critically on prioritizing responses to motivationally salient stimuli. While it is generally believed that motivational salience increases decision speed, the quantitative relationship between motivational salience and decision speed, measured by reaction time (RT), remains unclear. Here we show that the neural correlate of motivational salience in the basal forebrain (BF), defined independently of RT, is coupled with faster and also more precise decision speed. In rats performing a reward-biased simple RT task, motivational salience was encoded by BF bursting response that occurred before RT. We found that faster RTs were tightly coupled with stronger BF motivational salience signals. Furthermore, the fraction of RT variability reflecting the contribution of intrinsic noise in the decision-making process was actively suppressed in faster RT distributions with stronger BF motivational salience signals. Artificially augmenting the BF motivational salience signal via electrical stimulation led to faster and more precise RTs and supports a causal relationship. Together, these results not only describe for the first time, to our knowledge, the quantitative relationship between motivational salience and faster decision speed, they also reveal the quantitative coupling relationship between motivational salience and more precise RT. Our results further establish the existence of an early and previously unrecognized step in the decision-making process that determines both the RT speed and variability of the entire decision-making process and suggest that this novel decision step is dictated largely by the BF motivational salience signal. Finally, our study raises the hypothesis that the dysregulation of decision speed in conditions such as depression, schizophrenia, and cognitive aging may result from the functional impairment of the motivational salience signal encoded by the poorly understood noncholinergic BF neurons.
Avila, Irene; Lin, Shih-Chieh
2014-01-01
The survival of animals depends critically on prioritizing responses to motivationally salient stimuli. While it is generally believed that motivational salience increases decision speed, the quantitative relationship between motivational salience and decision speed, measured by reaction time (RT), remains unclear. Here we show that the neural correlate of motivational salience in the basal forebrain (BF), defined independently of RT, is coupled with faster and also more precise decision speed. In rats performing a reward-biased simple RT task, motivational salience was encoded by BF bursting response that occurred before RT. We found that faster RTs were tightly coupled with stronger BF motivational salience signals. Furthermore, the fraction of RT variability reflecting the contribution of intrinsic noise in the decision-making process was actively suppressed in faster RT distributions with stronger BF motivational salience signals. Artificially augmenting the BF motivational salience signal via electrical stimulation led to faster and more precise RTs and supports a causal relationship. Together, these results not only describe for the first time, to our knowledge, the quantitative relationship between motivational salience and faster decision speed, they also reveal the quantitative coupling relationship between motivational salience and more precise RT. Our results further establish the existence of an early and previously unrecognized step in the decision-making process that determines both the RT speed and variability of the entire decision-making process and suggest that this novel decision step is dictated largely by the BF motivational salience signal. Finally, our study raises the hypothesis that the dysregulation of decision speed in conditions such as depression, schizophrenia, and cognitive aging may result from the functional impairment of the motivational salience signal encoded by the poorly understood noncholinergic BF neurons. PMID:24642480
Cheng, Yuk Wah; Wilkinson, Jenny M
2015-08-01
This paper reports on an evaluation of the introduction of a blood bank automation system (Ortho AutoVue(®) Innova) in a hospital blood bank by considering the performance and workflow as compared with manual methods. The turnaround time was found to be 45% faster than the manual method. The concordance rate was found to be 100% for both ABO/Rh(D) typing and antibody screening in both of the systems and there was no significant difference in detection sensitivity for clinically significant antibodies. The Ortho AutoVue(®) Innova automated blood banking system streamlined the routine pre-transfusion testing in hospital blood bank with high throughput, equivalent sensitivity and reliability as compared with conventional manual method. Copyright © 2015 Elsevier Ltd. All rights reserved.
Concurrent processing of vehicle lane keeping and speech comprehension tasks.
Cao, Shi; Liu, Yili
2013-10-01
With the growing prevalence of using in-vehicle devices and mobile devices while driving, a major concern is their impact on driving performance and safety. However, the effects of cognitive load such as conversation on driving performance are still controversial and not well understood. In this study, an experiment was conducted to investigate the concurrent performance of vehicle lane keeping and speech comprehension tasks with improved experimental control of the confounding factors identified in previous studies. The results showed that the standard deviation of lane position (SDLP) was increased when the driving speed was faster (0.30 m at 36 km/h; 0.36 m at 72 km/h). The concurrent comprehension task had no significant effect on SDLP (0.34 m on average) or the standard deviation of steering wheel angle (SDSWA; 5.20° on average). The correct rate of the comprehension task was reduced in the dual-task condition (from 93.4% to 91.3%) compared with the comprehension single-task condition. Mental workload was significantly higher in the dual-task condition compared with the single-task conditions. Implications for driving safety were discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.
A Comparison of Mixed-Method Cooling Interventions on Preloaded Running Performance in the Heat.
Stevens, Christopher J; Bennett, Kyle J M; Sculley, Dean V; Callister, Robin; Taylor, Lee; Dascombe, Ben J
2017-03-01
Stevens, CJ, Bennett, KJM, Sculley, DV, Callister, R, Taylor, L, and Dascombe, BJ. A comparison of mixed-method cooling interventions on preloaded running performance in the heat. J Strength Cond Res 31(3): 620-629, 2017-The purpose of this investigation was to assess the effect of combining practical methods to cool the body on endurance running performance and physiology in the heat. Eleven trained male runners completed 4 randomized, preloaded running time trials (20 minutes at 70% V[Combining Dot Above]O2max and a 3 km time trial) on a nonmotorized treadmill in the heat (33° C). Trials consisted of precooling by combined cold-water immersion and ice slurry ingestion (PRE), midcooling by combined facial water spray and menthol mouth rinse (MID), a combination of all methods (ALL), and control (CON). Performance time was significantly faster in MID (13.7 ± 1.2 minutes; p < 0.01) and ALL (13.7 ± 1.4 minutes; p = 0.04) but not PRE (13.9 ± 1.4 minutes; p = 0.24) when compared with CON (14.2 ± 1.2 minutes). Precooling significantly reduced rectal temperature (initially by 0.5 ± 0.2° C), mean skin temperature, heart rate and sweat rate, and increased iEMG activity, whereas midcooling significantly increased expired air volume and respiratory exchange ratio compared with control. Significant decreases in forehead temperature, thermal sensation, and postexercise blood prolactin concentration were observed in all conditions compared with control. Performance was improved with midcooling, whereas precooling had little or no influence. Midcooling may have improved performance through an attenuated inhibitory psychophysiological and endocrine response to the heat.
The macular photostress test in diabetes, glaucoma, and cataract
NASA Astrophysics Data System (ADS)
Baptista, António M. G.; Sousa, Raul A. R. C.; Rocha, Filomena A. S. Q.; Fernandes, Paula Sepúlveda; Macedo, António F.
2013-11-01
Purpose. The photostress recovery time test (PSRT) has been widely reported as a helpful screening clinical tool. However, the poor standardization of its measurement technique remains to be a limitation among clinicians. The purpose of this study is to apply a recommended clinical technique to measure the PSRT in some of the most commons eye diseases to ascertain whether these diseases affect the PSRT values. Methods. One hundred and one controls and 105 patients, with diagnosed diabetes (without visible signs of diabetic retinopathy), primary open angle glaucoma (POAG) or cataracts underwent photostress testing. The test was performed with a direct ophthalmoscope for illuminating the macula for 30 seconds. Participants belonged to three age classes: A, B and C; and were divided into four groups: control, diabetic, POAG and cataract. The age range for A, B and C classes were respectively 43-54, 55-64 and 65-74 years. The groups were also further compared within each age class. In addition, the influence of age on PSRT was evaluated using the control group. Results. Results demonstrate that PSRT changes with age (p<0.02). In class A, diabetic group had a faster PSRT than control group, (mean +/- standard deviation) 20.22+/-7.51 and 26.14+/-8.34 seconds. The difference between these groups was statistical significant (t-test, p=0.012). Cataract and POAG groups did not affect the PSRT significantly. Conclusions. The technique used for the Photostress showed that diabetics, younger than 54 years, may have faster PSRT and that, aging delays PSRT.
Both anodal and cathodal transcranial direct current stimulation improves semantic processing.
Brückner, Sabrina; Kammer, Thomas
2017-02-20
Transcranial direct current stimulation (tDCS) is a common method to modulate cortical activity. Anodal tDCS is usually associated with an enhancement of the stimulated brain area, whereas cathodal tDCS is often described as inhibitory brain stimulation method. Our aim was to investigate whether this canonical assumption derived from the motor system could be transferred to the semantic system. Three groups with 20 healthy subjects each were stimulated at Wernicke's area with either anodal, cathodal or sham tDCS. Subsequently, they performed a simple lexical decision task for a duration of about 25min. Subjects receiving anodal tDCS revealed faster reaction times (RTs) compared to the sham group, although not reaching statistical significance. Surprisingly, in the cathodal group RTs were decreased significantly. All subjects were faster in the second half of the task, but the tDCS-induced improvement lasted for the entire duration of the task. Error rates were not influenced by tDCS, neither were RTs in a choice reaction time task. Thus, both anodal and cathodal tDCS applied to Wernicke's area improved semantic processing. Recently, a meta-analysis revealed that the canonical anodal excitation and cathodal inhibition assumption is observed rarely in cognitive studies. In particular, an inhibitory effect of cathodal tDCS on cognition is rare. Our findings thus support the speculation, that especially language functions could be somewhat 'immune' to cathodal inhibition. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.
Choosing the Most Effective Pattern Classification Model under Learning-Time Constraint.
Saito, Priscila T M; Nakamura, Rodrigo Y M; Amorim, Willian P; Papa, João P; de Rezende, Pedro J; Falcão, Alexandre X
2015-01-01
Nowadays, large datasets are common and demand faster and more effective pattern analysis techniques. However, methodologies to compare classifiers usually do not take into account the learning-time constraints required by applications. This work presents a methodology to compare classifiers with respect to their ability to learn from classification errors on a large learning set, within a given time limit. Faster techniques may acquire more training samples, but only when they are more effective will they achieve higher performance on unseen testing sets. We demonstrate this result using several techniques, multiple datasets, and typical learning-time limits required by applications.
NASA Technical Reports Server (NTRS)
Fowell, Richard A.
1989-01-01
Most simulation plots are heavily oversampled. Ignoring unnecessary data points dramatically reduces plot time with imperceptible effect on quality. The technique is suited to most plot devices. The departments laser printer's speed was tripled for large simulation plots by data thinning. This reduced printer delays without the expense of a faster laser printer. Surpisingly, it saved computer time as well. All plot data are now thinned, including PostScript and terminal plots. The problem, solution, and conclusions are described. The thinning algorithm is described and performance studies are presented. To obtain FORTRAN 77 or C source listings, mail a SASE to the author.
Anthropometric and performance comparisons in professional baseball players.
Hoffman, Jay R; Vazquez, Jose; Pichardo, Napoleon; Tenenbaum, Gershon
2009-11-01
This study compared anthropometric and performance variables in professional baseball players and examined the relationship between these variables and baseball-specific performance (i.e., home runs, total bases, slugging percentage, and stolen bases). During a 2-year period, 343 professional baseball players were assessed for height, weight, body composition, grip strength, vertical jump power, 10-yard sprint speed, and agility. Subject population consisted of players on the rosters of one of the minor league affiliates (Rookie, A, AA, AAA) or major league team (MLB). All testing occurred at the beginning of spring training. Players in Rookie and A were significantly (p < 0.05) leaner than players in MLB and AAA. These same players had significantly lower lean body mass than seen in MLB, AAA, and AA players. Greater grip strength (p < 0.05) was seen in MLB and AAA than in Rookie and A. Players in MLB were also faster (p < 0.05) than players in AA, A, and Rookie. Vertical jump power measures were greater (p < 0.05) in MLB than AA, A, and Rookie. Regression analysis revealed that performance measures accounted for 25-31% of the variance in baseball-specific power performance. Anthropometric measures failed to add any additional explanation to the variance in these baseball-specific performance variables. Results indicated that both anthropometric and performance variables differed between players of different levels of competition in professional baseball. Agility, speed, and lower-body power appeared to provide the greatest predictive power of baseball-specific performance.
Liu, Yang; Gao, Binghong; Li, Jiru; Ma, Zuchang; Sun, Yining
2018-06-07
The aim of this study was to investigate whether changes on foot-stretcher height were associated with characteristics of better rowing performance. Ten male rowers performed a 200 m rowing trial at their racing rate at each of three foot-stretcher heights. A single scull was equipped with an accelerometer to collect boat acceleration, an impeller with embedded magnets to collect boat speed, specially designed gate sensors to collect gate force and angle, and a compact string potentiometer to collect leg drive length. All sensor signals were sampled at 50 Hz. A one-way repeated measures ANOVA showed that raising foot-stretcher position had a significant reduction on total gate angle and leg drive length. However, a raised foot-stretcher position had a deeper negative peak of boat acceleration at the catch, a lower boat fluctuation, a faster leg drive speed, a larger gate force for the port and starboard side separately. This could be attributed to the optimisation of the magnitude and direction of the foot force with a raised foot-stretcher position. Although there was a significant negative influence of a raised foot-stretcher position on two kinematic variables, biomechanical evidence suggested that a raised foot-stretcher position could contribute to the improvement of rowing performance.
A Comparison of Selective Pressures in Plant X-Linked and Autosomal Genes
Krasovec, Marc; Filatov, Dmitry A.
2018-01-01
Selection is expected to work differently in autosomal and X-linked genes because of their ploidy difference and the exposure of recessive X-linked mutations to haploid selection in males. However, it is not clear whether these expectations apply to recently evolved sex chromosomes, where many genes retain functional X- and Y-linked gametologs. We took advantage of the recently evolved sex chromosomes in the plant Silene latifolia and its closely related species to compare the selective pressures between hemizygous and non-hemizygous X-linked genes as well as between X-linked genes and autosomal genes. Our analysis, based on over 1000 genes, demonstrated that, similar to animals, X-linked genes in Silene evolve significantly faster than autosomal genes—the so-called faster-X effect. Contrary to expectations, faster-X divergence was detectable only for non-hemizygous X-linked genes. Our phylogeny-based analyses of selection revealed no evidence for faster adaptation in X-linked genes compared to autosomal genes. On the other hand, partial relaxation of purifying selection was apparent on the X-chromosome compared to the autosomes, consistent with a smaller genetic diversity in S. latifolia X-linked genes (πx = 0.016; πaut = 0.023). Thus, the faster-X divergence in S. latifolia appears to be a consequence of the smaller effective population size rather than of a faster adaptive evolution on the X-chromosome. We argue that this may be a general feature of “young” sex chromosomes, where the majority of X-linked genes are not hemizygous, preventing haploid selection in heterogametic sex. PMID:29751495
A Comparison of Selective Pressures in Plant X-Linked and Autosomal Genes.
Krasovec, Marc; Nevado, Bruno; Filatov, Dmitry A
2018-05-03
Selection is expected to work differently in autosomal and X-linked genes because of their ploidy difference and the exposure of recessive X-linked mutations to haploid selection in males. However, it is not clear whether these expectations apply to recently evolved sex chromosomes, where many genes retain functional X- and Y-linked gametologs. We took advantage of the recently evolved sex chromosomes in the plant Silene latifolia and its closely related species to compare the selective pressures between hemizygous and non-hemizygous X-linked genes as well as between X-linked genes and autosomal genes. Our analysis, based on over 1000 genes, demonstrated that, similar to animals, X-linked genes in Silene evolve significantly faster than autosomal genes—the so-called faster-X effect. Contrary to expectations, faster-X divergence was detectable only for non-hemizygous X-linked genes. Our phylogeny-based analyses of selection revealed no evidence for faster adaptation in X-linked genes compared to autosomal genes. On the other hand, partial relaxation of purifying selection was apparent on the X-chromosome compared to the autosomes, consistent with a smaller genetic diversity in S. latifolia X-linked genes (π x = 0.016; π aut = 0.023). Thus, the faster-X divergence in S. latifolia appears to be a consequence of the smaller effective population size rather than of a faster adaptive evolution on the X-chromosome. We argue that this may be a general feature of “young” sex chromosomes, where the majority of X-linked genes are not hemizygous, preventing haploid selection in heterogametic sex.
Carrera, Adrián; Pifarré, Marc; Vilaplana, Jordi; Cuadrado, Josep; Solsona, Sara; Mateo, Jordi
2016-01-01
Summary Background Hypertension or high blood pressure is on the rise. Not only does it affect the elderly but is also increasingly spreading to younger sectors of the population. Treating this condition involves exhaustive monitoring of patients. The current mobile health services can be improved to perform this task more effectively. Objective To develop a useful, user-friendly, robust and efficient app, to monitor hypertensive patients and adapted to the particular requirements of hypertension. Methods This work presents BPcontrol, an Android and iOS app that allows hypertensive patients to communicate with their health-care centers, thus facilitating monitoring and diagnosis. Usability, robustness and efficiency factors for BPcontrol were evaluated for different devices and operating systems (Android, iOS and system-aware). Furthermore, its features were compared with other similar apps in the literature. Results BPcontrol is robust and user-friendly. The respective start-up efficiency of the Android and iOS versions of BPcontrol were 2.4 and 8.8 times faster than a system-aware app. Similar values were obtained for the communication efficiency (7.25 and 11.75 times faster for the Android and iOS respectively). When comparing plotting performance, BPcontrol was on average 2.25 times faster in the Android case. Most of the apps in the literature have no communication with a server, thus making it impossible to compare their performance with BPcontrol. Conclusions Its optimal design and the good behavior of its facilities make BPcontrol a very promising mobile app for monitoring hypertensive patients. PMID:27924346
BPcontrol. A Mobile App to Monitor Hypertensive Patients.
Carrera, Adrian; Pifarré, Marc; Vilaplana, Jordi; Cuadrado, Josep; Solsona, Sara; Mateo, Jordi; Solsona, Francesc
2016-12-07
Hypertension or high blood pressure is on the rise. Not only does it affect the elderly but is also increasingly spreading to younger sectors of the population. Treating this condition involves exhaustive monitoring of patients. The current mobile health services can be improved to perform this task more effectively. To develop a useful, user-friendly, robust and efficient app, to monitor hypertensive patients and adapted to the particular requirements of hypertension. This work presents BPcontrol, an Android and iOS app that allows hypertensive patients to communicate with their health-care centers, thus facilitating monitoring and diagnosis. Usability, robustness and efficiency factors for BPcontrol were evaluated for different devices and operating systems (Android, iOS and system-aware). Furthermore, its features were compared with other similar apps in the literature. BPcontrol is robust and user-friendly. The respective start-up efficiency of the Android and iOS versions of BPcontrol were 2.4 and 8.8 times faster than a system-aware app. Similar values were obtained for the communication efficiency (7.25 and 11.75 times faster for the Android and iOS respectively). When comparing plotting performance, BPcontrol was on average 2.25 times faster in the Android case. Most of the apps in the literature have no communication with a server, thus making it impossible to compare their performance with BPcontrol. Its optimal design and the good behavior of its facilities make BPcontrol a very promising mobile app for monitoring hypertensive patients.
Methodological Issues in Measures of Imitative Reaction Times
ERIC Educational Resources Information Center
Aicken, Michael D.; Wilson, Andrew D.; Williams, Justin H. G.; Mon-Williams, Mark
2007-01-01
Ideomotor (IM) theory suggests that observing someone else perform an action activates an internal motor representation of that behaviour within the observer. Evidence supporting the case for an ideomotor theory of imitation has come from studies that show imitative responses to be faster than the same behavioural measures performed in response to…
Real-time lens distortion correction: speed, accuracy and efficiency
NASA Astrophysics Data System (ADS)
Bax, Michael R.; Shahidi, Ramin
2014-11-01
Optical lens systems suffer from nonlinear geometrical distortion. Optical imaging applications such as image-enhanced endoscopy and image-based bronchoscope tracking require correction of this distortion for accurate localization, tracking, registration, and measurement of image features. Real-time capability is desirable for interactive systems and live video. The use of a texture-mapping graphics accelerator, which is standard hardware on current motherboard chipsets and add-in video graphics cards, to perform distortion correction is proposed. Mesh generation for image tessellation, an error analysis, and performance results are presented. It is shown that distortion correction using commodity graphics hardware is substantially faster than using the main processor and can be performed at video frame rates (faster than 30 frames per second), and that the polar-based method of mesh generation proposed here is more accurate than a conventional grid-based approach. Using graphics hardware to perform distortion correction is not only fast and accurate but also efficient as it frees the main processor for other tasks, which is an important issue in some real-time applications.
Novices in surgery are the target group of a virtual reality training laboratory.
Hassan, Iyad; Maschuw, Katja; Rothmund, Matthias; Koller, Michael; Gerdes, Berthold
2006-01-01
This study aims to establish which physicians represent the suitable target group of a virtual training laboratory. Novices (48 physicians with fewer than 10 laparoscopic operations) and intermediate trainees (19 physicians who performed 30-50 laparoscopic operations) participated in this study. Each participant performed the basic module 'clip application' at the beginning and after a 1-hour short training course on the LapSim. The course consisted of the tasks coordination, lift and grasp, clip application, cutting with diathermy and fine dissection at increasing difficulty levels. The time taken to complete the tasks, number of errors, and economy of motion parameters (path length and angular path) were analyzed. Following training with the simulator, novices completed the task significantly faster (p = 0.001), demonstrated a greater economy of motion [path length (p = 0.04) and angular path (p = 0.01)]. In contrast, the intermediate trainees showed a reduction of their errors, but without reaching statistical significance. They showed no improvement in economy of motion and completed the task significantly slower (p = 0.03). Novices, in comparison to intermediate trainees, tend to benefit most during their first exposure to a laparoscopy simulator.
Castro, Lauren A; Peterson, Jennifer K; Saldana, Azael; Perea, Milixa Y; Calzada, Jose E; Pineda, Vanessa; Dobson, Andrew P; Gottdenker, Nicole L
2014-09-01
ABSTRACT Flight dispersal of the triatomine bug species Rhodnius pallescens Barber, the principal vector of Chagas disease in Panama, is an important mechanism for spreading Trypanosoma cruzi, causative agent of Chagas disease. This study measures R. pallescens flight performance using a tethered flight mill both when uninfected, and when infected with T. cruzi or Trypanosoma rangeli. Forty-four out of the 48 (91.7%) insects initiated flight across all treatments, and trypanosome infection did not significantly impact flight initiation. Insects from all treatments flew a cumulative distance ranging from 0.5 to 5 km before fatiguing. The median cumulative distance flown before insect fatigue was higher in T. cruzi- and T. rangeli-infected insects than in control insects; however, this difference was not statistically significant. There was a positive relationship between parasite load ingested and time until flight initiation in T. rangeli-infected bugs, and T. rangeli- and T. cruzi-infected females flew significantly faster than males at different time points. These novel findings allow for a better understanding of R. pallescens dispersal ability and peridomestic management strategies for the prevention of Chagas disease in Panama.
The effects of precompetition massage on the kinematic parameters of 20-m sprint performance.
Fletcher, Iain M
2010-05-01
The purpose of this study was to investigate what effect precompetition massage has on short-term sprint performance. Twenty male collegiate games players, with a minimum training/playing background of 3 sessions per week, were assigned to a randomized, counter-balanced, repeated-measures designed experiment used to analyze 20-m sprints performance. Three discrete warm-up modalities, consisting of precompetition massage, a traditional warm-up, and a precompetition massage combined with a traditional warm-up were used. Massage consisted of fast, superficial techniques designed to stimulate the main muscle groups associated with sprint running. Twenty-meter sprint performance and core temperature were assessed post warm-up interventions. Kinematic differences between sprints were assessed through a 2-dimensional computerized motion analysis system (alpha level p
An improved method to detect correct protein folds using partial clustering.
Zhou, Jianjun; Wishart, David S
2013-01-16
Structure-based clustering is commonly used to identify correct protein folds among candidate folds (also called decoys) generated by protein structure prediction programs. However, traditional clustering methods exhibit a poor runtime performance on large decoy sets. We hypothesized that a more efficient "partial" clustering approach in combination with an improved scoring scheme could significantly improve both the speed and performance of existing candidate selection methods. We propose a new scheme that performs rapid but incomplete clustering on protein decoys. Our method detects structurally similar decoys (measured using either C(α) RMSD or GDT-TS score) and extracts representatives from them without assigning every decoy to a cluster. We integrated our new clustering strategy with several different scoring functions to assess both the performance and speed in identifying correct or near-correct folds. Experimental results on 35 Rosetta decoy sets and 40 I-TASSER decoy sets show that our method can improve the correct fold detection rate as assessed by two different quality criteria. This improvement is significantly better than two recently published clustering methods, Durandal and Calibur-lite. Speed and efficiency testing shows that our method can handle much larger decoy sets and is up to 22 times faster than Durandal and Calibur-lite. The new method, named HS-Forest, avoids the computationally expensive task of clustering every decoy, yet still allows superior correct-fold selection. Its improved speed, efficiency and decoy-selection performance should enable structure prediction researchers to work with larger decoy sets and significantly improve their ab initio structure prediction performance.
An improved method to detect correct protein folds using partial clustering
2013-01-01
Background Structure-based clustering is commonly used to identify correct protein folds among candidate folds (also called decoys) generated by protein structure prediction programs. However, traditional clustering methods exhibit a poor runtime performance on large decoy sets. We hypothesized that a more efficient “partial“ clustering approach in combination with an improved scoring scheme could significantly improve both the speed and performance of existing candidate selection methods. Results We propose a new scheme that performs rapid but incomplete clustering on protein decoys. Our method detects structurally similar decoys (measured using either Cα RMSD or GDT-TS score) and extracts representatives from them without assigning every decoy to a cluster. We integrated our new clustering strategy with several different scoring functions to assess both the performance and speed in identifying correct or near-correct folds. Experimental results on 35 Rosetta decoy sets and 40 I-TASSER decoy sets show that our method can improve the correct fold detection rate as assessed by two different quality criteria. This improvement is significantly better than two recently published clustering methods, Durandal and Calibur-lite. Speed and efficiency testing shows that our method can handle much larger decoy sets and is up to 22 times faster than Durandal and Calibur-lite. Conclusions The new method, named HS-Forest, avoids the computationally expensive task of clustering every decoy, yet still allows superior correct-fold selection. Its improved speed, efficiency and decoy-selection performance should enable structure prediction researchers to work with larger decoy sets and significantly improve their ab initio structure prediction performance. PMID:23323835
Nagaoka, Tomoaki; Watanabe, Soichi
2012-01-01
Electromagnetic simulation with anatomically realistic computational human model using the finite-difference time domain (FDTD) method has recently been performed in a number of fields in biomedical engineering. To improve the method's calculation speed and realize large-scale computing with the computational human model, we adapt three-dimensional FDTD code to a multi-GPU cluster environment with Compute Unified Device Architecture and Message Passing Interface. Our multi-GPU cluster system consists of three nodes. The seven GPU boards (NVIDIA Tesla C2070) are mounted on each node. We examined the performance of the FDTD calculation on multi-GPU cluster environment. We confirmed that the FDTD calculation on the multi-GPU clusters is faster than that on a multi-GPU (a single workstation), and we also found that the GPU cluster system calculate faster than a vector supercomputer. In addition, our GPU cluster system allowed us to perform the large-scale FDTD calculation because were able to use GPU memory of over 100 GB.
Improved performance in NASTRAN (R)
NASA Technical Reports Server (NTRS)
Chan, Gordon C.
1989-01-01
Three areas of improvement in COSMIC/NASTRAN, 1989 release, were incorporated recently that make the analysis program run faster on large problems. Actual log files and actual timings on a few test samples that were run on IBM, CDC, VAX, and CRAY computers were compiled. The speed improvement is proportional to the problem size and number of continuation cards. Vectorizing certain operations in BANDIT, makes BANDIT run twice as fast in some large problems using structural elements with many node points. BANDIT is a built-in NASTRAN processor that optimizes the structural matrix bandwidth. The VAX matrix packing routine BLDPK was modified so that it is now packing a column of a matrix 3 to 9 times faster. The denser and bigger the matrix, the greater is the speed improvement. This improvement makes a host of routines and modules that involve matrix operation run significantly faster, and saves disc space for dense matrices. A UNIX version, converted from 1988 COSMIC/NASTRAN, was tested successfully on a Silicon Graphics computer using the UNIX V Operating System, with Berkeley 4.3 Extensions. The Utility Modules INPUTT5 and OUTPUT5 were expanded to handle table data, as well as matrices. Both INPUTT5 and OUTPUT5 are general input/output modules that read and write FORTRAN files with or without format. More user informative messages are echoed from PARAMR, PARAMD, and SCALAR modules to ensure proper data values and data types being handled. Two new Utility Modules, GINOFILE and DATABASE, were written for the 1989 release. Seven rigid elements are added to COSMIC/NASTRAN. They are: CRROD, CRBAR, CRTRPLT, CRBE1, CRBE2, CRBE3, and CRSPLINE.
Koschate, Jessica; Drescher, Uwe; Brinkmann, Christian; Baum, Klaus; Schiffer, Thorsten; Latsch, Joachim; Brixius, Klara; Hoffmann, Uwe
2016-11-01
Cardiorespiratory kinetics were analyzed in type 2 diabetes patients before and after a 12-week endurance exercise-training intervention. It was hypothesized that muscular oxygen uptake and heart rate (HR) kinetics would be faster after the training intervention and that this would be detectable using a standardized work rate protocol with pseudo-random binary sequences. The cardiorespiratory kinetics of 13 male sedentary, middle-aged, overweight type 2 diabetes patients (age, 60 ± 8 years; body mass index, 33 ± 4 kg·m -2 ) were tested before and after the 12-week exercise intervention. Subjects performed endurance training 3 times a week on nonconsecutive days. Pseudo-random binary sequences exercise protocols in combination with time series analysis were used to estimate kinetics. Greater maxima in cross-correlation functions (CCF max ) represent faster kinetics of the respective parameter. CCF max of muscular oxygen uptake (pre-training: 0.31 ± 0.03; post-training: 0.37 ± 0.1, P = 0.024) and CCF max of HR (pre-training: 0.25 ± 0.04; post-training: 0.29 ± 0.06, P = 0.007) as well as peak oxygen uptake (pre-training: 24.4 ± 4.7 mL·kg -1 ·min -1 ; post-training: 29.3 ± 6.5 mL·kg -1 ·min -1 , P = 0.004) increased significantly over the course of the exercise intervention. In conclusion, kinetic responses to changing work rates in the moderate-intensity range are similar to metabolic demands occurring in everyday habitual activities. Moderate endurance training accelerated the kinetic responses of HR and muscular oxygen uptake. Furthermore, the applicability of the used method to detect these accelerations was demonstrated.
NASA Technical Reports Server (NTRS)
Leutenegger, Scott T.; Horton, Graham
1994-01-01
Recently the Multi-Level algorithm was introduced as a general purpose solver for the solution of steady state Markov chains. In this paper, we consider the performance of the Multi-Level algorithm for solving Nearly Completely Decomposable (NCD) Markov chains, for which special-purpose iteractive aggregation/disaggregation algorithms such as the Koury-McAllister-Stewart (KMS) method have been developed that can exploit the decomposability of the the Markov chain. We present experimental results indicating that the general-purpose Multi-Level algorithm is competitive, and can be significantly faster than the special-purpose KMS algorithm when Gauss-Seidel and Gaussian Elimination are used for solving the individual blocks.
Vitale, Jacopo A; Bonato, Matteo; Galasso, Letizia; La Torre, Antonio; Merati, Giampiero; Montaruli, Angela; Roveda, Eliana; Carandente, Franca
2017-01-01
The influence of the chronotype on the sleep quality in male collegiate soccer players in response to acute high intensity interval training (HIIT) performed at two different times of day was evaluated. The sleep quality was poorer in the morning-type than in the evening-type players after the evening HIIT session, whereas no significant changes in the sleep quality of the two chronotypes after the morning HIIT session was observed. The results suggest that an athlete's chronotype should be taken into account when scheduling training sessions and to promote faster recovery processes.
A Programming Model Performance Study Using the NAS Parallel Benchmarks
Shan, Hongzhang; Blagojević, Filip; Min, Seung-Jai; ...
2010-01-01
Harnessing the power of multicore platforms is challenging due to the additional levels of parallelism present. In this paper we use the NAS Parallel Benchmarks to study three programming models, MPI, OpenMP and PGAS to understand their performance and memory usage characteristics on current multicore architectures. To understand these characteristics we use the Integrated Performance Monitoring tool and other ways to measure communication versus computation time, as well as the fraction of the run time spent in OpenMP. The benchmarks are run on two different Cray XT5 systems and an Infiniband cluster. Our results show that in general the threemore » programming models exhibit very similar performance characteristics. In a few cases, OpenMP is significantly faster because it explicitly avoids communication. For these particular cases, we were able to re-write the UPC versions and achieve equal performance to OpenMP. Using OpenMP was also the most advantageous in terms of memory usage. Also we compare performance differences between the two Cray systems, which have quad-core and hex-core processors. We show that at scale the performance is almost always slower on the hex-core system because of increased contention for network resources.« less
An Effective Hybrid Evolutionary Algorithm for Solving the Numerical Optimization Problems
NASA Astrophysics Data System (ADS)
Qian, Xiaohong; Wang, Xumei; Su, Yonghong; He, Liu
2018-04-01
There are many different algorithms for solving complex optimization problems. Each algorithm has been applied successfully in solving some optimization problems, but not efficiently in other problems. In this paper the Cauchy mutation and the multi-parent hybrid operator are combined to propose a hybrid evolutionary algorithm based on the communication (Mixed Evolutionary Algorithm based on Communication), hereinafter referred to as CMEA. The basic idea of the CMEA algorithm is that the initial population is divided into two subpopulations. Cauchy mutation operators and multiple paternal crossover operators are used to perform two subpopulations parallelly to evolve recursively until the downtime conditions are met. While subpopulation is reorganized, the individual is exchanged together with information. The algorithm flow is given and the performance of the algorithm is compared using a number of standard test functions. Simulation results have shown that this algorithm converges significantly faster than FEP (Fast Evolutionary Programming) algorithm, has good performance in global convergence and stability and is superior to other compared algorithms.
NASA Technical Reports Server (NTRS)
Rorie, Conrad; Fern, Lisa; Pack, Jessica; Shively, Jay; Draper, Mark H.
2015-01-01
The pilot-in-the-loop Detect-and-Avoid (DAA) task requires the pilot to carry out three major functions: 1) detect a potential threat, 2) determine an appropriate resolution maneuver, and 3) execute that resolution maneuver via the GCS control and navigation interface(s). The purpose of the present study was to examine two main questions with respect to DAA display considerations that could impact pilots ability to maintain well clear from other aircraft. First, what is the effect of a minimum (or basic) information display compared to an advanced information display on pilot performance? Second, what is the effect of display location on UAS pilot performance? Two levels of information level (basic, advanced) were compared across two levels of display location (standalone, integrated), for a total of four displays. The results indicate that the advanced displays had faster overall response times compared to the basic displays, however, there were no significant differences between the standalone and integrated displays.
NASA Astrophysics Data System (ADS)
Rizki, Permata Nur Miftahur; Lee, Heezin; Lee, Minsu; Oh, Sangyoon
2017-01-01
With the rapid advance of remote sensing technology, the amount of three-dimensional point-cloud data has increased extraordinarily, requiring faster processing in the construction of digital elevation models. There have been several attempts to accelerate the computation using parallel methods; however, little attention has been given to investigating different approaches for selecting the most suited parallel programming model for a given computing environment. We present our findings and insights identified by implementing three popular high-performance parallel approaches (message passing interface, MapReduce, and GPGPU) on time demanding but accurate kriging interpolation. The performances of the approaches are compared by varying the size of the grid and input data. In our empirical experiment, we demonstrate the significant acceleration by all three approaches compared to a C-implemented sequential-processing method. In addition, we also discuss the pros and cons of each method in terms of usability, complexity infrastructure, and platform limitation to give readers a better understanding of utilizing those parallel approaches for gridding purposes.
Effect of motion cues during complex curved approach and landing tasks: A piloted simulation study
NASA Technical Reports Server (NTRS)
Scanlon, Charles H.
1987-01-01
A piloted simulation study was conducted to examine the effect of motion cues using a high fidelity simulation of commercial aircraft during the performance of complex approach and landing tasks in the Microwave Landing System (MLS) signal environment. The data from these tests indicate that in a high complexity MLS approach task with moderate turbulence and wind, the pilot uses motion cues to improve path tracking performance. No significant differences in tracking accuracy were noted for the low and medium complexity tasks, regardless of the presence of motion cues. Higher control input rates were measured for all tasks when motion was used. Pilot eye scan, as measured by instrument dwell time, was faster when motion cues were used regardless of the complexity of the approach tasks. Pilot comments indicated a preference for motion. With motion cues, pilots appeared to work harder in all levels of task complexity and to improve tracking performance in the most complex approach task.
Johari, Karim; Behroozmand, Roozbeh
2017-08-01
Skilled movement is mediated by motor commands executed with extremely fine temporal precision. The question of how the brain incorporates temporal information to perform motor actions has remained unanswered. This study investigated the effect of stimulus temporal predictability on response timing of speech and hand movement. Subjects performed a randomized vowel vocalization or button press task in two counterbalanced blocks in response to temporally-predictable and unpredictable visual cues. Results indicated that speech and hand reaction time was decreased for predictable compared with unpredictable stimuli. This finding suggests that a temporal predictive code is established to capture temporal dynamics of sensory cues in order to produce faster movements in responses to predictable stimuli. In addition, results revealed a main effect of modality, indicating faster hand movement compared with speech. We suggest that this effect is accounted for by the inherent complexity of speech production compared with hand movement. Lastly, we found that movement inhibition was faster than initiation for both hand and speech, suggesting that movement initiation requires a longer processing time to coordinate activities across multiple regions in the brain. These findings provide new insights into the mechanisms of temporal information processing during initiation and inhibition of speech and hand movement. Copyright © 2017 Elsevier B.V. All rights reserved.
H-BLAST: a fast protein sequence alignment toolkit on heterogeneous computers with GPUs.
Ye, Weicai; Chen, Ying; Zhang, Yongdong; Xu, Yuesheng
2017-04-15
The sequence alignment is a fundamental problem in bioinformatics. BLAST is a routinely used tool for this purpose with over 118 000 citations in the past two decades. As the size of bio-sequence databases grows exponentially, the computational speed of alignment softwares must be improved. We develop the heterogeneous BLAST (H-BLAST), a fast parallel search tool for a heterogeneous computer that couples CPUs and GPUs, to accelerate BLASTX and BLASTP-basic tools of NCBI-BLAST. H-BLAST employs a locally decoupled seed-extension algorithm for better performance on GPUs, and offers a performance tuning mechanism for better efficiency among various CPUs and GPUs combinations. H-BLAST produces identical alignment results as NCBI-BLAST and its computational speed is much faster than that of NCBI-BLAST. Speedups achieved by H-BLAST over sequential NCBI-BLASTP (resp. NCBI-BLASTX) range mostly from 4 to 10 (resp. 5 to 7.2). With 2 CPU threads and 2 GPUs, H-BLAST can be faster than 16-threaded NCBI-BLASTX. Furthermore, H-BLAST is 1.5-4 times faster than GPU-BLAST. https://github.com/Yeyke/H-BLAST.git. yux06@syr.edu. Supplementary data are available at Bioinformatics online. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com
DOE Office of Scientific and Technical Information (OSTI.GOV)
Flueck, Alex
The “High Fidelity, Faster than RealTime Simulator for Predicting Power System Dynamic Behavior” was designed and developed by Illinois Institute of Technology with critical contributions from Electrocon International, Argonne National Laboratory, Alstom Grid and McCoy Energy. Also essential to the project were our two utility partners: Commonwealth Edison and AltaLink. The project was a success due to several major breakthroughs in the area of largescale power system dynamics simulation, including (1) a validated faster than real time simulation of both stable and unstable transient dynamics in a largescale positive sequence transmission grid model, (2) a threephase unbalanced simulation platform formore » modeling new grid devices, such as independently controlled singlephase static var compensators (SVCs), (3) the world’s first high fidelity threephase unbalanced dynamics and protection simulator based on Electrocon’s CAPE program, and (4) a firstofits kind implementation of a singlephase induction motor model with stall capability. The simulator results will aid power grid operators in their true time of need, when there is a significant risk of cascading outages. The simulator will accelerate performance and enhance accuracy of dynamics simulations, enabling operators to maintain reliability and steer clear of blackouts. In the longterm, the simulator will form the backbone of the newly conceived hybrid realtime protection and control architecture that will coordinate local controls, widearea measurements, widearea controls and advanced realtime prediction capabilities. The nation’s citizens will benefit in several ways, including (1) less down time from power outages due to the fasterthanrealtime simulator’s predictive capability, (2) higher levels of reliability due to the detailed dynamics plus protection simulation capability, and (3) more resiliency due to the three phase unbalanced simulator’s ability to model threephase and single phase networks and devices.« less
Freeman, Benjamin G; Montgomery, Graham A; Schluter, Dolph
2017-09-01
Plasticity is often thought to accelerate trait evolution and speciation. For example, plasticity in birdsong may partially explain why clades of song learners are more diverse than related clades with innate song. This "song learning" hypothesis predicts that (1) differences in song traits evolve faster in song learners, and (2) behavioral discrimination against allopatric song (a proxy for premating reproductive isolation) evolves faster in song learners. We tested these predictions by analyzing acoustic traits and conducting playback experiments in allopatric Central American sister pairs of song learning oscines (N = 42) and nonlearning suboscines (N = 27). We found that nonlearners evolved mean acoustic differences slightly faster than did leaners, and that the mean evolutionary rate of song discrimination was 4.3 times faster in nonlearners than in learners. These unexpected results may be a consequence of significantly greater variability in song traits in song learners (by 54-79%) that requires song-learning oscines to evolve greater absolute differences in song before achieving the same level of behavioral song discrimination as nonlearning suboscines. This points to "a downside of learning" for the evolution of species discrimination, and represents an important example of plasticity reducing the rate of evolution and diversification by increasing variability. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.
Lu, Xi; Siu, Ka-Chun; Fu, Siu N; Hui-Chan, Christina W Y; Tsang, William W N
2013-08-01
To compare the performance of older experienced Tai Chi practitioners and healthy controls in dual-task versus single-task paradigms, namely stepping down with and without performing an auditory response task, a cross-sectional study was conducted in the Center for East-meets-West in Rehabilitation Sciences at The Hong Kong Polytechnic University, Hong Kong. Twenty-eight Tai Chi practitioners (73.6 ± 4.2 years) and 30 healthy control subjects (72.4 ± 6.1 years) were recruited. Participants were asked to step down from a 19-cm-high platform and maintain a single-leg stance for 10 s with and without a concurrent cognitive task. The cognitive task was an auditory Stroop test in which the participants were required to respond to different tones of voices regardless of their word meanings. Postural stability after stepping down under single- and dual-task paradigms, in terms of excursion of the subject's center of pressure (COP) and cognitive performance, was measured for comparison between the two groups. Our findings demonstrated significant between-group differences in more outcome measures during dual-task than single-task performance. Thus, the auditory Stroop test showed that Tai Chi practitioners achieved not only significantly less error rate in single-task, but also significantly faster reaction time in dual-task, when compared with healthy controls similar in age and other relevant demographics. Similarly, the stepping-down task showed that Tai Chi practitioners not only displayed significantly less COP sway area in single-task, but also significantly less COP sway path than healthy controls in dual-task. These results showed that Tai Chi practitioners achieved better postural stability after stepping down as well as better performance in auditory response task than healthy controls. The improved performance that was magnified by dual motor-cognitive task performance may point to the benefits of Tai Chi being a mind-and-body exercise.
Anthropometric and Performance Measures for High School Basketball Players
Greene, Joseph J.; McGuine, Timothy A.; Leverson, Glen; Best, Thomas M.
1998-01-01
Objective: To determine possible anthropometric and performance sex differences in a population of high school basketball players. Design and Setting: Measurements were collected during the first week of basketball practice before the 1995-1996 season. Varsity basketball players from 4 high schools were tested on a battery of measures chosen to detect possible anthropometric and performance sex differences. Subjects: Fifty-four female and sixty-one male subjects, from varsity basketball teams at high schools enrolled in the athletic training outreach program at the University of Wisconsin Hospital Sports Medicine Center in Madison, WI, volunteered to take part in this study. Measurements: We took anthropometric measurements on each of the 115 subjects. These included height, weight, body composition, ankle range of motion, and medial longitudinal arch type in weightbearing. Performance measures included the vertical jump, 22.86-m (25-yd) shuttle run, 18.29-m (20-yd) sprint, and single-limb balance time. Results: We compared anthropometric and performance characteristics using a 2-sample t test. The only exception to this was for medial longitudinal arch type, where the 2 groups were compared using a 2-tailed Fisher's exact test. The male subjects were significantly taller and heavier, while the females had a significantly higher percentage of body fat. There were no significant differences found for ankle plantar flexion and dorsiflexion, but the females had significantly more inversion and eversion range of motion. Analysis of medial longitudinal arch type found females to have a higher percentage of pronated arches and males to have a higher percentage of supinated arches. Performance testing revealed that the males were able to jump significantly higher and run the 22.86-m (25-yard) shuttle run and 18.29-m (20-yard) sprint significantly faster than the female subjects. There was no significant difference between the groups for single-limb balance time. Conclusions: We found significant anthropometric and performance sex differences in a cohort of high school basketball players. Further study of these measures is necessary to determine if these differences can predict the risk for ankle injuries in this particular population. PMID:16558515
Belci, D; Kos, M; Zoricić, D; Kuharić, L; Slivar, A; Begić-Razem, E; Grdinić, I
2007-06-01
The aim of this study was to evaluate the advantages of the Misgav Ladach surgical technique compared to traditional cesarean section. A prospective randomized trial of 111 women undergoing cesarean section was carried out in the Pula General Hospital. Forty-nine operations were performed using the Pfannenstiel method of cesarean section, 55 by the Misgav Ladach method and 7 by lower midline laparotomy. It was proved that the cases where the Misgav Ladach method was implemented, compared to the Pfannenstiel method, showed a significantly shorter delivery/extraction and operative time (P=0.0009), the incision pain on the second postoperative day was significantly lower (0.021), we recorded a quicker stand up and walking time (P=0.013), significantly fewer analgesic injections and a shorter duration of analgesia were required (P=0.0009) and the bowel function was restored to normal sooner (P=0.001). The Misgav Ladach method of cesarean section has advantages over the Pfannenstiel method in so far as it is significantly quicker to perform, with diminished postoperative pain and less use of postoperative analgesics. The recovery of physiologic function is faster. No differences were found in intraoperative bleeding, maternal morbidity, scar appearance, uterus postoperative involution and the assessment of the inflammation response to the operative technique.
Honarvar, Mohammad Reza; Eghtesadi, Shahryar; Gill, Pooria; Jazayeri, Shima; Vakili, Mohammad Ali; Shamsardekani, Mohammad Reza; Abbasi, Abdollah
2016-01-01
Background: Acceleration in sputum smear conversion helps faster improvement and decreased probability of the transfer of TB. In this study, we aimed to investigate the effect of green tea extract supplementation on sputum smear conversion and weight changes in smear positive pulmonary TB patients in Iran. Methods: In this double blind clinical study, TB patients were divided into intervention, (n=43) receiving 500 mg green tea extract (GTE), and control groups (n=40) receiving placebo for two months, using balanced randomization. Random allocation and allocation concealment were observed. Height and weight were measured at the beginning, and two and six months post-treatment. Evaluations were performed on three slides, using the ZiehlNeelsen method. Independent and paired t test, McNemar’s, Wilcoxon, Kaplan-Meier, Cox regression model and Log-Rank test were utilized. Statistical significance was set at p<0.05. This trial was registered under IRCT201212232602N11. Results: The interventional changes and the interactive effect of intervention on weight were not significant (p>0.05). In terms of shortening the duration of conversion, the case to control proportion showed a significant difference (p=0.032). Based on the Cox regression model, the hazard ratio of the relative risk of delay in sputum smear conversion was 3.7 (p=0.002) in the higher microbial load group compared to the placebo group and 0.54 (95% CI: 0.31-0.94) in the intervention compared to the placebo group. Conclusion: GTE decreases the risk of delay in sputum smear conversion, but has no effect on weight gain. Moreover, it may be used as an adjuvant therapy for faster rehabilitation for pulmonary TB patients. PMID:27493925
Faghihi, Gita; Iraji, Fariba; Rajaee Harandi, Manijeh; Nilforoushzadeh, Mohammad-Ali; Askari, Gholamreza
2013-01-01
According to the hypothesis on the stimulating effect of adenosine on increasing fibroblast growth factor 7 in dermal papilla cells and its vasorelaxant effect, we performed this study to compare the effect of topical minoxidil 5% and adenosine 0.75% on male pattern androgenetic alopecia. This prospective-randomized study recruited 110 male patients suffering from grade II-V Hamilton androgenetic alopecia. Fifty-five patients received minoxidil 5% (group 1) and adenosine 0.75% (group 2) each. Later, 16 patients were excluded due to allergic reactions or loss to follow up. After 3 and 6 months of treatment, complete and relative recovery rates alongside patient satisfaction rate (faster prevention of primary hair loss and appearance of newly grown hair) were compared between the groups. After 3 months of treatment, relative recovery was achieved in 2.4% and 1.9% of patients in group 1 and group 2, respectively, which was not significantly different (p=0.17). During 6 months, the relative recovery rate did not change either within or between the groups (p=0.99) and after 6 months none of the patients achieved complete recovery. However, the patient satisfaction rate was significantly higher in group 2 (p=0.003). In the light of the results, adenosine has no statistically superiority to minoxidil in the treatment of androgenetic alopecia according to recovery rates. However, the patients were significantly more satisfied with adenosine because of faster prevention of hair loss and appearance of the newly grown hairs. It seems further studies with larger sample size or different drug dosages are required to clarify the findings.
NASA Astrophysics Data System (ADS)
Wang, Jinniu; Xu, Bo; Wu, Yan; Gao, Jing; Shi, Fusun
2016-10-01
Litters of reproductive organs have rarely been studied despite their role in allocating nutrients for offspring reproduction. This study determines the mechanism through which flower litters efficiently increase the available soil nutrient pool. Field experiments were conducted to collect plant litters and calculate biomass production in an alpine meadow of the eastern Tibetan Plateau. C, N, P, lignin, cellulose content, and their relevant ratios of litters were analyzed to identify their decomposition features. A pot experiment was performed to determine the effects of litter addition on the soil nutrition pool by comparing the treated and control samples. The litter-bag method was used to verify decomposition rates. The flower litters of phanerophyte plants were comparable with non-flower litters. Biomass partitioning of other herbaceous species accounted for 10-40 % of the aboveground biomass. Flower litter possessed significantly higher N and P levels but less C / N, N / P, lignin / N, and lignin and cellulose concentrations than leaf litter. The litter-bag experiment confirmed that the flower litters of Rhododendron przewalskii and Meconopsis integrifolia decompose approximately 3 times faster than mixed litters within 50 days. Pot experiment findings indicated that flower litter addition significantly increased the available nutrient pool and soil microbial productivity. The time of litter fall significantly influenced soil available N and P, and soil microbial biomass. Flower litters fed the soil nutrition pool and influenced nutrition cycling in alpine ecosystems more efficiently because of their non-ignorable production, faster decomposition rate, and higher nutrient contents compared with non-flower litters. The underlying mechanism can enrich nutrients, which return to the soil, and non-structural carbohydrates, which feed and enhance the transitions of soil microorganisms.
Piqueras-Fiszman, Betina; Kraus, Alexandra A; Spence, Charles
2014-07-01
Wanting and rejecting food are natural reactions that we humans all experience, often unconsciously, on a daily basis. However, in the food domain, the focus to date has primarily been on the approach tendency, and researchers have tended not to study the two opposing tendencies in a balanced manner. Here, we develop a methodology with which to understand people's implicit and explicit reactions to both positive (appealing) and negative (disgusting) foods. It consists of a combination of direct and indirect computer-based tasks, as well as a validated food image stimulus set, specifically designed to investigate motivational approach and avoidance responses towards foods. Fifty non-dieting participants varying in terms of their hunger state (hungry vs. not hungry) reported their explicit evaluations of pleasantness, wanting, and disgust towards the idea of tasting each of the food images that were shown. Their motivational tendencies towards those food items were assessed indirectly using a joystick-based approach-avoidance procedure. For each of the food images that were presented, the participants had to move the joystick either towards or away from themselves (approach and avoidance movements, respectively) according to some unrelated instructions, while their reaction times were recorded. Our findings demonstrated the hypothesised approach-avoidance compatibility effect: a significant interaction of food valence and direction of movement. Furthermore, differences between the experimental groups were observed. The participants in the no-hunger group performed avoidance (vs. approach) movements significantly faster; and their approach movements towards positive (vs. negative) foods were significantly faster. As expected, the self-report measures revealed a strong effect of the food category on the three dependent variables and a strong main effect of the hunger state on wanting and to a lesser extent on pleasantness. Copyright © 2014 Elsevier Ltd. All rights reserved.
Leaf breakdown in streams differing in catchment land use
Paul, M.J.; Meyer, J.L.; Couch, C.A.
2006-01-01
1. The impact of changes in land use on stream ecosystem function is poorly understood. We studied leaf breakdown, a fundamental process of stream ecosystems, in streams that represent a range of catchment land use in the Piedmont physiographic province of the south-eastern United States. 2. We placed bags of chalk maple (Acer barbatum) leaves in similar-sized streams in 12 catchments of differing dominant land use: four forested, three agricultural, two suburban and three urban catchments. We measured leaf mass, invertebrate abundance and fungal biomass in leaf bags over time. 3. Leaves decayed significantly faster in agricultural (0.0465 day-1) and urban (0.0474 day-1) streams than in suburban (0.0173 day-1) and forested (0.0100 day-1) streams. Additionally, breakdown rates in the agricultural and urban streams were among the fastest reported for deciduous leaves in any stream. Nutrient concentrations in agricultural streams were significantly higher than in any other land-use type. Fungal biomass associated with leaves was significantly lower in urban streams; while shredder abundance in leaf bags was significantly higher in forested and agricultural streams than in suburban and urban streams. Storm runoff was significantly higher in urban and suburban catchments that had higher impervious surface cover than forested or agricultural catchments. 4. We propose that processes accelerating leaf breakdown in agricultural and urban streams were not the same: faster breakdown in agricultural streams was due to increased biological activity as a result of nutrient enrichment, whereas faster breakdown in urban streams was a result of physical fragmentation resulting from higher storm runoff. ?? 2006 The Authors.
Auditory and Visual Interhemispheric Communication in Musicians and Non-Musicians
Woelfle, Rebecca; Grahn, Jessica A.
2013-01-01
The corpus callosum (CC) is a brain structure composed of axon fibres linking the right and left hemispheres. Musical training is associated with larger midsagittal cross-sectional area of the CC, suggesting that interhemispheric communication may be faster in musicians. Here we compared interhemispheric transmission times (ITTs) for musicians and non-musicians. ITT was measured by comparing simple reaction times to stimuli presented to the same hemisphere that controlled a button-press response (uncrossed reaction time), or to the contralateral hemisphere (crossed reaction time). Both visual and auditory stimuli were tested. We predicted that the crossed-uncrossed difference (CUD) for musicians would be smaller than for non-musicians as a result of faster interhemispheric transfer times. We did not expect a difference in CUDs between the visual and auditory modalities for either musicians or non-musicians, as previous work indicates that interhemispheric transfer may happen through the genu of the CC, which contains motor fibres rather than sensory fibres. There were no significant differences in CUDs between musicians and non-musicians. However, auditory CUDs were significantly smaller than visual CUDs. Although this auditory-visual difference was larger in musicians than non-musicians, the interaction between modality and musical training was not significant. Therefore, although musical training does not significantly affect ITT, the crossing of auditory information between hemispheres appears to be faster than visual information, perhaps because subcortical pathways play a greater role for auditory interhemispheric transfer. PMID:24386382
Whipple, Brittany D; Nelson, Jason M
2016-02-01
This study investigated the performance of adolescents and young adults with Attention Deficit Hyperactivity Disorder (ADHD), Reading Disorder (RD), and ADHD/RD on measures of alphanumeric and nonalphanumeric naming speed and the relationship between naming speed and academic achievement. The sample (N = 203) included students aged 17-28 years diagnosed with ADHD (n = 83), RD (n = 71), or ADHD/RD (n = 49). Individuals with ADHD performed significantly faster on measures of alphanumeric naming compared with RD and comorbid groups and, within group, demonstrated significantly quicker naming of letters/digits compared with colors/objects. Both alphanumeric rapid naming scores and processing speed scores variably predicted academic achievement scores across groups, whereas nonalphanumeric rapid naming only predicted reading comprehension scores within the ADHD group. Results support findings that older individuals with ADHD show relative weakness in rapid naming of objects and colors. Implications of these findings in regard to assessment of older individuals for ADHD are discussed. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Effects of color scheme and message lines of variable message signs on driver performance.
Lai, Chien-Jung
2010-07-01
The advancement in variable message signs (VMS) technology has made it possible to display message with various formats. This study presented an ergonomic study on the message design of Chinese variable message signs on urban roads in Taiwan. Effects of color scheme (one, two and three) and number of message lines (single, double and triple) of VMS on participants' response performance were investigated through a laboratory experiment. Results of analysis showed that color scheme and number of message lines are significant factors for participants' response time to VMS. Participants responded faster for two-color than for one- and three-color scheme. Participants also took less response time for double line message than for single and triple line message. Both color scheme and number of message lines had no significant effect on participants' response accuracy. The preference survey after the experiment showed that most participants preferred two-color scheme and double line message to the other combinations. The results can assist in adopting appropriate color scheme and number of message lines of Chinese VMS. Copyright 2009 Elsevier Ltd. All rights reserved.
P50 Sensory Gating and Attentional Performance
Wan, Li; Friedman, Bruce H.; Boutros, Nash N.; Crawford, Helen J.
2008-01-01
Sensory gating refers to the preattentional filtering of irrelevant sensory stimuli. This process may be impaired in schizotypy, which is a trait also associated with cigarette smoking. This association may in part stem from the positive effects of smoking on sensory gating and attention. The relationship among sensory gating, smoking, schizotypy and attention was examined in 39 undergraduates. Sensory gating was indexed by the P50 suppression paradigm, and attention was measured by the Attention Network Test (ANT) and a Stroop task. Results showed sensory gating to be positively correlated with performances on ANT and Stroop reflected in better alerting, less conflict between stimuli, faster reaction time, and greater accuracy. Smokers showed a pattern of a greater number of significant correlations between sensory gating and attention in comparison to non-smokers, although the relationship between sensory gating and attention was not affected by schizotypy. The majority of significant correlations were found in the region surrounding Cz. These findings are discussed relative to the potential modifying influence of smoking and schizotypy on sensory gating and attention. PMID:18036692
Faster, Less Expensive Dies Using RSP Tooling
NASA Astrophysics Data System (ADS)
Knirsch, James R.
2007-08-01
RSP Tooling is an indirect spray form additive process that can produce production tooling for virtually any forming process and from virtually any metal. In the past 24 months a significant amount of research and development has been performed. This resulted in an increase in the basic metallurgical understanding of what transpires during the rapid solidification of the metal, significant improvements in the production machine up time, ceramic developments that have improved finish, process changes that have resulted in a shorter lead time for tool delivery, and the testing of many new alloys. RSP stands for Rapid Solidification Process and is the key to the superior metallurgical properties that result from the technology. Most metals that are sprayed in the process leave the machine with the same physical properties as the same metal normally achieves through heat treatment and in some cases the properties are superior. Many new applications are being pursued including INVAR tools for aerospace composite materials, and bimetallic tools made from tool steel and beryllium copper for die casting and plastic injection molding. Recent feasibility studies have been performed with tremendous success.
Wheel slip control with torque blending using linear and nonlinear model predictive control
NASA Astrophysics Data System (ADS)
Basrah, M. Sofian; Siampis, Efstathios; Velenis, Efstathios; Cao, Dongpu; Longo, Stefano
2017-11-01
Modern hybrid electric vehicles employ electric braking to recuperate energy during deceleration. However, currently anti-lock braking system (ABS) functionality is delivered solely by friction brakes. Hence regenerative braking is typically deactivated at a low deceleration threshold in case high slip develops at the wheels and ABS activation is required. If blending of friction and electric braking can be achieved during ABS events, there would be no need to impose conservative thresholds for deactivation of regenerative braking and the recuperation capacity of the vehicle would increase significantly. In addition, electric actuators are typically significantly faster responding and would deliver better control of wheel slip than friction brakes. In this work we present a control strategy for ABS on a fully electric vehicle with each wheel independently driven by an electric machine and friction brake independently applied at each wheel. In particular we develop linear and nonlinear model predictive control strategies for optimal performance and enforcement of critical control and state constraints. The capability for real-time implementation of these controllers is assessed and their performance is validated in high fidelity simulation.
The behavior of an opponent alters pacing decisions in 4-km cycling time trials.
Konings, Marco J; Schoenmakers, Patrick P J M; Walker, Andrew J; Hettinga, Florentina J
2016-05-01
The present study aimed to explore how athletes respond to different behaviors of their opponents. Twelve moderately to highly physically active participants with at least two years of cycling experience completed four 4-km time trials on a Velotron cycle ergometer. After a familiarization time trial (FAM), participants performed three experimental time trials in randomized order with no opponent (NO), a virtual opponent who started slower and finished faster compared to FAM (OP-SLOWFAST), or a virtual opponent who started faster and finished slower compared to FAM (OP-FASTSLOW). Repeated-measures ANOVAs (P<0.05) were used to examine differences in pacing and performance related to power output, velocity and RPE. OP-SLOWFAST and OP-FASTSLOW were completed faster compared to NO (385.5±27.5, 385.0±28.6, and 390.6±29.3s, respectively). An interaction effect for condition×distance (F=3.944, P<0.001) indicated differences in pacing profiles between conditions. Post-hoc analysis revealed that a less aggressive starting strategy was adopted in NO compared to OP-FASTSLOW and OP-SLOWFAST during the initial 1000m. Finally, a faster starting opponent evokes higher power outputs by the participants in the initial 750m compared to a slower starting opponent. The present study is the first to show that the behavior of an opponent affects pacing-related decisions in laboratory-controlled conditions. Our findings support the recently proposed interdependence of perception and action, and emphasize the interaction with the environment as an important determinant for an athlete's pacing decisions, especially during the initial stages of a race. Copyright © 2016 Elsevier Inc. All rights reserved.
Ocean acidification changes the male fitness landscape.
Campbell, Anna L; Levitan, Don R; Hosken, David J; Lewis, Ceri
2016-08-17
Sperm competition is extremely common in many ecologically important marine taxa. Ocean acidification (OA) is driving rapid changes to the marine environments in which freely spawned sperm operate, yet the consequences of OA on sperm performance are poorly understood in the context of sperm competition. Here, we investigated the impacts of OA (+1000 μatm pCO2) on sperm competitiveness for the sea urchin Paracentrotus lividus. Males with faster sperm had greater competitive fertilisation success in both seawater conditions. Similarly, males with more motile sperm had greater sperm competitiveness, but only under current pCO2 levels. Under OA the strength of this association was significantly reduced and there were male sperm performance rank changes under OA, such that the best males in current conditions are not necessarily best under OA. Therefore OA will likely change the male fitness landscape, providing a mechanism by which environmental change alters the genetic landscape of marine species.
Ocean acidification changes the male fitness landscape
NASA Astrophysics Data System (ADS)
Campbell, Anna L.; Levitan, Don R.; Hosken, David J.; Lewis, Ceri
2016-08-01
Sperm competition is extremely common in many ecologically important marine taxa. Ocean acidification (OA) is driving rapid changes to the marine environments in which freely spawned sperm operate, yet the consequences of OA on sperm performance are poorly understood in the context of sperm competition. Here, we investigated the impacts of OA (+1000 μatm pCO2) on sperm competitiveness for the sea urchin Paracentrotus lividus. Males with faster sperm had greater competitive fertilisation success in both seawater conditions. Similarly, males with more motile sperm had greater sperm competitiveness, but only under current pCO2 levels. Under OA the strength of this association was significantly reduced and there were male sperm performance rank changes under OA, such that the best males in current conditions are not necessarily best under OA. Therefore OA will likely change the male fitness landscape, providing a mechanism by which environmental change alters the genetic landscape of marine species.
Sharifahmadian, Ershad
2006-01-01
The set partitioning in hierarchical trees (SPIHT) algorithm is very effective and computationally simple technique for image and signal compression. Here the author modified the algorithm which provides even better performance than the SPIHT algorithm. The enhanced set partitioning in hierarchical trees (ESPIHT) algorithm has performance faster than the SPIHT algorithm. In addition, the proposed algorithm reduces the number of bits in a bit stream which is stored or transmitted. I applied it to compression of multichannel ECG data. Also, I presented a specific procedure based on the modified algorithm for more efficient compression of multichannel ECG data. This method employed on selected records from the MIT-BIH arrhythmia database. According to experiments, the proposed method attained the significant results regarding compression of multichannel ECG data. Furthermore, in order to compress one signal which is stored for a long time, the proposed multichannel compression method can be utilized efficiently.
Efficient similarity-based data clustering by optimal object to cluster reallocation.
Rossignol, Mathias; Lagrange, Mathieu; Cont, Arshia
2018-01-01
We present an iterative flat hard clustering algorithm designed to operate on arbitrary similarity matrices, with the only constraint that these matrices be symmetrical. Although functionally very close to kernel k-means, our proposal performs a maximization of average intra-class similarity, instead of a squared distance minimization, in order to remain closer to the semantics of similarities. We show that this approach permits the relaxing of some conditions on usable affinity matrices like semi-positiveness, as well as opening possibilities for computational optimization required for large datasets. Systematic evaluation on a variety of data sets shows that compared with kernel k-means and the spectral clustering methods, the proposed approach gives equivalent or better performance, while running much faster. Most notably, it significantly reduces memory access, which makes it a good choice for large data collections. Material enabling the reproducibility of the results is made available online.
Implementation of Multispectral Image Classification on a Remote Adaptive Computer
NASA Technical Reports Server (NTRS)
Figueiredo, Marco A.; Gloster, Clay S.; Stephens, Mark; Graves, Corey A.; Nakkar, Mouna
1999-01-01
As the demand for higher performance computers for the processing of remote sensing science algorithms increases, the need to investigate new computing paradigms its justified. Field Programmable Gate Arrays enable the implementation of algorithms at the hardware gate level, leading to orders of m a,gnitude performance increase over microprocessor based systems. The automatic classification of spaceborne multispectral images is an example of a computation intensive application, that, can benefit from implementation on an FPGA - based custom computing machine (adaptive or reconfigurable computer). A probabilistic neural network is used here to classify pixels of of a multispectral LANDSAT-2 image. The implementation described utilizes Java client/server application programs to access the adaptive computer from a remote site. Results verify that a remote hardware version of the algorithm (implemented on an adaptive computer) is significantly faster than a local software version of the same algorithm implemented on a typical general - purpose computer).
NASA Astrophysics Data System (ADS)
Balcerzak, Marek; Dąbrowski, Artur; Pikunov, Danylo
2018-01-01
This paper presents a practical application of a new, simplified method of Lyapunov exponents estimation. The method has been applied to optimization of a real, nonlinear inverted pendulum system. Authors presented how the algorithm of the Largest Lyapunov Exponent (LLE) estimation can be applied to evaluate control systems performance. The new LLE-based control performance index has been proposed. Equations of the inverted pendulum system of the fourth order have been found. The nonlinear friction of the regulation object has been identified by means of the nonlinear least squares method. Three different friction models have been tested: linear, cubic and Coulomb model. The Differential Evolution (DE) algorithm has been used to search for the best set of parameters of the general linear regulator. This work proves that proposed method is efficient and results in faster perturbation rejection, especially when disturbances are significant.
Ma, Li; Stübinger, Stefan; Liu, Xi Ling; Schneider, Urs A; Lang, Niklaus P
2013-08-01
The purpose of this study was to compare bone healing of experimental osteotomies applying either piezosurgery or two different oscillating saw blades in a rabbit model. The 16 rabbits were randomly assigned into four groups to comply with observation periods of one, two, three and five weeks. In all animals, four osteotomy lines were performed on the left and right nasal bone using a conventional saw blade, a novel saw blade and piezosurgery. All three osteotomy techniques revealed an advanced gap healing starting after one week. The most pronounced new bone formation took place between two and three weeks, whereby piezoelectric surgery revealed a tendency to faster bone formation and remodelling. Yet, there were no significant differences between the three modalities. The use of a novel as well as the piezoelectric bone-cutting instrument revealed advanced bone healing with a favourable surgical performance compared to a traditional saw.
Yin, Zhouping; Wang, Xiaomei; Sun, Fazhe; Tong, Xiaohu; Zhu, Chen; Lv, Qiying; Ye, Dong; Wang, Shuai; Luo, Wei; Huang, YongAn
2017-09-22
Gas sensing performance can be improved significantly by the increase in both the effective gas exposure area and the surface reactivitiy of ZnO nanorods. Here, we propose aligned hierarchical Ag/ZnO nano-heterostructure arrays (h-Ag/ZnO-NAs) via electrohydrodynamic nanowire template, together with a subsequent hydrothermal synthesis and photoreduction reaction. The h-Ag/ZnO-NAs scatter at top for higher specific surface areas with the air, simultaneously contact at root for the electrical conduction. Besides, the ZnO nanorods are uniformly coated with dispersed Ag nanoparticles, resulting in a tremendous enhancement of the surface reactivity. Compared with pure ZnO, such h-Ag/ZnO-NAs exhibit lower electrical resistance and faster responses. Moreover, they demonstrate enhanced NO 2 gas sensing properties. Self-assembly via electrohydrodynamic nanowire template paves a new way for the preparation of high performance gas sensors.
Agarkar, Smita; Hurt, Stephen W; Young, Robert C
2018-07-01
We reviewed studies that reported speed of antidepressant response to electroconvulsive therapy (ECT) in both bipolar depression (BPD) and major depressive disorder (MDD). We identified English language reports allowing this comparison. Ten studies met our criteria. Four reported significantly faster response in BPD and in one there was trend for faster response. None reported evidence for slower response in BPD. The findings support further study of speed of response to ECT in BPD. Copyright © 2018 Elsevier B.V. All rights reserved.
Effects of shape and stroke parameters on the propulsion performance of an axisymmetric swimmer.
Peng, Jifeng; Alben, Silas
2012-03-01
In nature, there exists a special group of aquatic animals which have an axisymmetric body and whose primary swimming mechanism is to use periodic body contractions to generate vortex rings in the surrounding fluid. Using jellyfish medusae as an example, this study develops a mathematical model of body kinematics of an axisymmetric swimmer and uses a computational approach to investigate the induced vortex wakes. Wake characteristics are identified for swimmers using jet propulsion and rowing, two mechanisms identified in previous studies of medusan propulsion. The parameter space of body kinematics is explored through four quantities: a measure of body shape, stroke amplitude, the ratio between body contraction duration and extension duration, and the pulsing frequency. The effects of these parameters on thrust, input power requirement and circulation production are quantified. Two metrics, cruising speed and energy cost of locomotion, are used to evaluate the propulsion performance. The study finds that a more prolate-shaped swimmer with larger stroke amplitudes is able to swim faster, but its cost of locomotion is also higher. In contrast, a more oblate-shaped swimmer with smaller stroke amplitudes uses less energy for its locomotion, but swims more slowly. Compared with symmetric strokes with equal durations of contraction and extension, faster bell contractions increase the swimming speed whereas faster bell extensions decrease it, but both require a larger energy input. This study shows that besides the well-studied correlations between medusan body shape and locomotion, stroke variables also affect the propulsion performance. It provides a framework for comparing the propulsion performance of axisymmetric swimmers based on their body kinematics when it is difficult to measure and analyze their wakes empirically. The knowledge from this study is also useful for the design of robotic swimmers that use axisymmetric body contractions for propulsion.
suk O, Jin; Jeen, Sung-Wook; Gillham, Robert W; Gui, Lai
2009-01-26
Column experiments and numerical simulation were conducted to test the hypothesis that iron material having a high corrosion rate is not beneficial for the long-term performance of iron permeable reactive barriers (PRBs) because of faster passivation of iron and greater porosity loss close to the influent face of the PRBs. Four iron materials (Connelly, Gotthart-Maier, Peerless, and ISPAT) were used for the column experiments, and the changes in reactivity toward cis-dichloroethene (cis-DCE) degradation in the presence of dissolved CaCO3 were evaluated. The experimental results showed that the difference in distribution of the accumulated precipitates, resulting from differences in iron corrosion rate, caused a difference in the migration rate of the cis-DCE profiles and a significant difference in the pattern of passivation, indicating a faster passivation in the region close to the influent end for the material having a higher corrosion rate. For the numerical simulation, the accumulation of secondary minerals and reactivity loss of iron were coupled using an empirically-derived relationship that was incorporated into a multi-component reactive transport model. The simulation results provided a reasonable representation of the evolution of iron reactivity toward cis-DCE treatment and the changes in geochemical conditions for each material, consistent with the observed data. The simulations for long-term performance were also conducted to further test the hypothesis and predict the differences in performance over a period of 40 years under typical groundwater conditions. The predictions showed that the cases of higher iron corrosion rates had earlier cis-DCE breakthrough and more reduction in porosity starting from near the influent face, due to more accumulation of carbonate minerals in that region. Therefore, both the experimental and simulation results appear to support the hypothesis and suggest that reactivity changes of iron materials resulting from evolution of geochemical conditions should be considered in the design of iron PRBs.
Fast Dynamic Simulation-Based Small Signal Stability Assessment and Control
DOE Office of Scientific and Technical Information (OSTI.GOV)
Acharya, Naresh; Baone, Chaitanya; Veda, Santosh
2014-12-31
Power grid planning and operation decisions are made based on simulation of the dynamic behavior of the system. Enabling substantial energy savings while increasing the reliability of the aging North American power grid through improved utilization of existing transmission assets hinges on the adoption of wide-area measurement systems (WAMS) for power system stabilization. However, adoption of WAMS alone will not suffice if the power system is to reach its full entitlement in stability and reliability. It is necessary to enhance predictability with "faster than real-time" dynamic simulations that will enable the dynamic stability margins, proactive real-time control, and improve gridmore » resiliency to fast time-scale phenomena such as cascading network failures. Present-day dynamic simulations are performed only during offline planning studies, considering only worst case conditions such as summer peak, winter peak days, etc. With widespread deployment of renewable generation, controllable loads, energy storage devices and plug-in hybrid electric vehicles expected in the near future and greater integration of cyber infrastructure (communications, computation and control), monitoring and controlling the dynamic performance of the grid in real-time would become increasingly important. The state-of-the-art dynamic simulation tools have limited computational speed and are not suitable for real-time applications, given the large set of contingency conditions to be evaluated. These tools are optimized for best performance of single-processor computers, but the simulation is still several times slower than real-time due to its computational complexity. With recent significant advances in numerical methods and computational hardware, the expectations have been rising towards more efficient and faster techniques to be implemented in power system simulators. This is a natural expectation, given that the core solution algorithms of most commercial simulators were developed decades ago, when High Performance Computing (HPC) resources were not commonly available.« less
Influence of 2D and 3D view on performance and time estimation in minimal invasive surgery.
Blavier, A; Nyssen, A S
2009-11-01
This study aimed to evaluate the impact of two-dimensional (2D) and three-dimensional (3D) images on time performance and time estimation during a surgical motor task. A total of 60 subjects without any surgical experience (nurses) and 20 expert surgeons performed a fine surgical task with a new laparoscopic technology (da Vinci robotic system). The 80 subjects were divided into two groups, one using 3D view option and the other using 2D view option. We measured time performance and asked subjects to verbally estimate their time performance. Our results showed faster performance in 3D than in 2D view for novice subjects while the performance in 2D and 3D was similar in the expert group. We obtained a significant interaction between time performance and time evaluation: in 2D condition, all subjects accurately estimated their time performance while they overestimated it in the 3D condition. Our results emphasise the role of 3D in improving performance and the contradictory feeling about time evaluation in 2D and 3D. This finding is discussed in regard with the retrospective paradigm and suggests that 2D and 3D images are differently processed and memorised.
Performance of a distributed superscalar storage server
NASA Technical Reports Server (NTRS)
Finestead, Arlan; Yeager, Nancy
1993-01-01
The RS/6000 performed well in our test environment. The potential exists for the RS/6000 to act as a departmental server for a small number of users, rather than as a high speed archival server. Multiple UniTree Disk Server's utilizing one UniTree Disk Server's utilizing one UniTree Name Server could be developed that would allow for a cost effective archival system. Our performance tests were clearly limited by the network bandwidth. The performance gathered by the LibUnix testing shows that UniTree is capable of exceeding ethernet speeds on an RS/6000 Model 550. The performance of FTP might be significantly faster if asked to perform across a higher bandwidth network. The UniTree Name Server also showed signs of being a potential bottleneck. UniTree sites that would require a high ratio of file creations and deletions to reads and writes would run into this bottleneck. It is possible to improve the UniTree Name Server performance by bypassing the UniTree LibUnix Library altogether and communicating directly with the UniTree Name Server and optimizing creations. Although testing was performed in a less than ideal environment, hopefully the performance statistics stated in this paper will give end-users a realistic idea as to what performance they can expect in this type of setup.
DeMaria, S; Berman, D J; Goldberg, A; Lin, H-M; Khelemsky, Y; Levine, A I
2016-07-01
Non-operating room (non-OR) airway management has previously been identified as an area of concern because it carries a significant risk for complications. One reason for this could be attributed to the independent practice of residents in these situations. The aim of the present study was to ascertain whether differences in performance exist between residents working alone vs with a resident partner when encountering simulated non-OR airway management scenarios. Thirty-six anaesthesia residents were randomized into two groups. Each group experienced three separate scenarios (two scenarios initially and then a third 6 weeks later). The scenarios consisted of one control scenario and two critical event scenarios [i.e. asystole during laryngoscopy and pulseless electrical activity (PEA) upon post-intubation institution of positive pressure ventilation]. One group experienced the simulated non-OR scenarios alone (Solo group). The other group consisted of resident pairs, participating in the same three scenarios (Team group). Although the time to intubation did not differ between the Solo and Team groups, there were several differences in performance. The Team group received better overall performance ratings for the asystole (8.5 vs 5.5 out of 10; P<0.001) and PEA (8.5 vs 5.8 out of 10; P<0.001) scenarios. The Team group was also able to recognize asystole and PEA conditions faster than the Solo group [10.1 vs 23.5 s (P<0.001) and 13.3 vs 36.0 s (P<0.001), respectively]. Residents who performed a simulated intubation with a second trained provider had better overall performance than those who practised independently. The residents who practised in a group were also faster to diagnose serious complications, including peri-intubation asystole and PEA. Given these data, it is reasonable that training programmes consider performing all non-OR airway management with a team-based method. © The Author 2016. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Teaching high-performance skills using above-real-time training
NASA Technical Reports Server (NTRS)
Guckenberger, Dutch; Uliano, Kevin C.; Lane, Norman E.
1993-01-01
The above real-time training (ARTT) concept is an approach to teaching high-performance skills. ARTT refers to a training paradigm that places the operator in a simulated environment that functions at faster than normal time. It represents a departure from the intuitive, but not often supported, feeling that the best practice is determined by the training environment with the highest fidelity. This approach is hypothesized to provide greater 'transfer value' per simulation trial, by incorporating training techniques and instructional features into the simulator. Two related experiments are discussed. In the first, 25 naive male subjects performed three tank gunnery tasks on a simulator under varying levels of time acceleration (i.e., 1.0x, 1.6x, 2.0x, sequential, and mixed). They were then transferred to a standard (1.0x) condition for testing. Every accelerated condition or combination of conditions produced better training and transfer than the standard condition. Most effective was the presentation of trials at 1.0x, 1.6x, and 2.0x in a random order during training. Overall, the best ARTT group scored about 50 percent higher and trained in 25 percent less time compared to the real-time control group. In the second experiment, 24 mission-capable F-16 pilots performed three tasks on a part-task F-16A flight simulator under varying levels of time compression (i.e., 1.0x, 1.5x, 2.0x, and random). All subjects were then tested in a real-time environment. The emergency procedure (EP) task results showed increased accuracy for the ARTT groups. In testing (transfer), the ARTT groups not only performed the EP more accurately, but dealt with a simultaneous enemy significantly better than a real-time control group. Although the findings on an air combat maneuvering task and stern conversion task were mixed, most measures indicated that the ARTT groups performed better and faster than a real-time control group. Other implications for ARTT are discussed along with future research directions.
McMorris, Terry; Sproule, John; Turner, Anthony; Hale, Beverley J
2011-03-01
The purpose of this study was to compare, using meta-analytic techniques, the effect of acute, intermediate intensity exercise on the speed and accuracy of performance of working memory tasks. It was hypothesized that acute, intermediate intensity exercise would have a significant beneficial effect on response time and that effect sizes for response time and accuracy data would differ significantly. Random-effects meta-analysis showed a significant, beneficial effect size for response time, g=-1.41 (p<0.001) but a significant detrimental effect size, g=0.40 (p<0.01), for accuracy. There was a significant difference between effect sizes (Z(diff)=3.85, p<0.001). It was concluded that acute, intermediate intensity exercise has a strong beneficial effect on speed of response in working memory tasks but a low to moderate, detrimental one on accuracy. There was no support for a speed-accuracy trade-off. It was argued that exercise-induced increases in brain concentrations of catecholamines result in faster processing but increases in neural noise may negatively affect accuracy. 2010 Elsevier Inc. All rights reserved.
Virtual reality robotic surgical simulation: an analysis of gynecology trainees.
Sheth, Sangini S; Fader, Amanda N; Tergas, Ana I; Kushnir, Christina L; Green, Isabel C
2014-01-01
To analyze the learning curves of gynecology trainees on several virtual reality da Vinci Skills Simulator exercises. Prospective cohort pilot study. Academic hospital-based gynecology training program. Novice robotic surgeons from a gynecology training program. Novice robotic surgeons from an academic gynecology training program completed 10 repetitions of 4 exercises on the da Vinci Skills Simulator: matchboard, ring and rail, suture sponge, and energy switching. Performance metrics measured included time to completion, economy of instrument movement, excessive force, collisions, master workspace range, missed targets, misapplied energy, critical errors, and overall score. Statistical analyses were conducted to define the learning curve for trainees and the optimal number of repetitions for each exercise. A total of 34 participants were enrolled, of which 9 were medical students, 22 were residents, and 3 were fellows. There was a significant improvement in performance between the 1st and 10th repetitions across multiple metrics for all exercises. Senior trainees performed the suture exercise significantly faster than the junior trainees during the first and last repetitions (p = 0.004 and p = 0.003, respectively). However, the performance gap between seniors and juniors narrowed significantly by the 10th repetition. The mean number of repetitions required to achieve performance plateau ranged from 6.4 to 9.3. Virtual reality robotic simulation improves ability through repetition at all levels of training. Further, a performance plateau may exist during a single training session. Larger studies are needed to further define the most high-yield simulator exercises, the ideal number of repetitions, and recommended intervals between training sessions to improve operative performance. Copyright © 2014 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.
Self-confidence and affect responses to short-term sprint interval training.
Selmi, Walid; Rebai, Haithem; Chtara, Mokhtar; Naceur, Abdelmajid; Sahli, Sonia
2018-05-01
The study aimed to investigate the effects of repeated sprint (RS) training on somatic anxiety (SA), cognitive anxiety (CA), self-confidence (SC), rating of perceived exertion (RPE) and repeated sprint ability (RSA) indicators in elite young soccer players. Thirty elite soccer players in the first football league (age: 17.8±0.9years) volunteered to participate in this study. They were randomly assigned to one of two groups: a repeated sprint training group (RST-G; n=15) and a control group (CON-G; n=15). RST-G participated in 6weeks of intensive training based on RS (6×(20+20m) runs, with 20s passive recovery interval between sprints, 3 times/week). Before and after the 6-week intervention, all participants performed a RSA test and completed a Competitive Scale Anxiety Inventory (CSAI-2) and the RPE. After training RST-G showed a very significant (p<0.000) increase in RSA total time performance relative to controls. Despite the faster sprint pace, the RPE also decreased significantly (p<0.005) in RST-G, and their self confidence was significantly greater (p<0.01), while the cognitive (p<0.01) and somatic (p<0.000) components of their anxiety state decreased. When practiced regularly, short bouts of sprint exercises improve anaerobic performance associated with a reduction in anxiety state and an increase in SC which may probably boost competitive performance. Copyright © 2018 Elsevier Inc. All rights reserved.
The Importance of Moisture in Hybrid Lead Halide Perovskite Thin Film Fabrication.
Eperon, Giles E; Habisreutinger, Severin N; Leijtens, Tomas; Bruijnaers, Bardo J; van Franeker, Jacobus J; deQuilettes, Dane W; Pathak, Sandeep; Sutton, Rebecca J; Grancini, Giulia; Ginger, David S; Janssen, Rene A J; Petrozza, Annamaria; Snaith, Henry J
2015-09-22
Moisture, in the form of ambient humidity, has a significant impact on methylammonium lead halide perovskite films. In particular, due to the hygroscopic nature of the methylammonium component, moisture plays a significant role during film formation. This issue has so far not been well understood and neither has the impact of moisture on the physical properties of resultant films. Herein, we carry out a comprehensive and well-controlled study of the effect of moisture exposure on methylammonium lead halide perovskite film formation and properties. We find that films formed in higher humidity atmospheres have a less continuous morphology but significantly improved photoluminescence, and that film formation is faster. In photovoltaic devices, we find that exposure to moisture, either in the precursor solution or in the atmosphere during formation, results in significantly improved open-circuit voltages and hence overall device performance. We then find that by post-treating dry films with moisture exposure, we can enhance photovoltaic performance and photoluminescence in a similar way. The enhanced photoluminescence and open-circuit voltage imply that the material quality is improved in films that have been exposed to moisture. We determine that this improvement stems from a reduction in trap density in the films, which we postulate to be due to the partial solvation of the methylammonium component and "self-healing" of the perovskite lattice. This work highlights the importance of controlled moisture exposure when fabricating high-performance perovskite devices and provides guidelines for the optimum environment for fabrication. Moreover, we note that often an unintentional water exposure is likely responsible for the high performance of solar cells produced in some laboratories, whereas careful synthesis and fabrication in a dry environment will lead to lower-performing devices.
Performance of the Cell processor for biomolecular simulations
NASA Astrophysics Data System (ADS)
De Fabritiis, G.
2007-06-01
The new Cell processor represents a turning point for computing intensive applications. Here, I show that for molecular dynamics it is possible to reach an impressive sustained performance in excess of 30 Gflops with a peak of 45 Gflops for the non-bonded force calculations, over one order of magnitude faster than a single core standard processor.
ERIC Educational Resources Information Center
Fabusoro, E.; Awotunde, J. A.; Sodiya, C. I.; Alarima, C. I.
2008-01-01
The field level extension agents (FLEAs) are the lifeline of the agricultural extension system in Nigeria. Their motivation and job performance are therefore important to achieving faster agricultural development in Nigeria. The study identified the factors motivating the FLEAs working with Ogun State Agricultural development programme (OGADEP)…
An Explanation of the Superior Performance IQs of Deaf Children of Deaf Parents.
ERIC Educational Resources Information Center
Braden, Jeffery P.
1987-01-01
Differences in performance IQs between deaf children of hearing parents (HP), deaf children of deaf parents (DP), and hearing children (HC) may be a result of differences in speed of information processing. DP adolescents were found to have faster reaction and movement times than HP or HC subjects along with equivalent IQs. (Author/VW)
Sirin, Selma; Goericke, Sophia L; Huening, Britta M; Stein, Anja; Kinner, Sonja; Felderhoff-Mueser, Ursula; Schweiger, Bernd
2013-10-01
Several studies have revealed the importance of brain imaging in term and preterm infants. The aim of this retrospective study was to review safety, handling, and image quality of MR brain imaging using a new 3 Tesla MR-compatible incubator. Between 02/2011 and 05/2012 100 brain MRIs (84 infants, mean gestational age 32.2 ± 4.7 weeks, mean postmenstrual age at imaging 40.6 ± 3.4 weeks) were performed using a 3 Tesla MR-compatible incubator with dedicated, compatible head coil. Seventeen examinations (13 infants, mean gestational age 35.1 ± 5.4 weeks, mean postmenstrual age at imaging 47.8 ± 7.4 weeks) with a standard head coil served as a control. Image analysis was performed by a neuroradiologist and a pediatric radiologist in consensus. All but two patients with known apnea were transferred to the MR unit and scanned without problems. Handling was easier and faster with the incubator; relevant motion artifacts (5.9 vs. 10.8%) and the need for repetitive sedation (43.0 vs. 86.7%) were reduced. Considering only images not impaired by motion artifacts, image quality (4.8 ± 0.4 vs. 4.3 ± 0.8, p = 0.047) and spatial resolution (4.7 ± 0.4 vs. 4.2 ± 0.6, p = 0.011) of T2-weighted images were scored significantly higher in patients imaged with the incubator. SNR increased significantly (171.6 ± 54.5 vs. 80.5 ± 19.8, p < 0.001) with the use of the incubator. Infants can benefit from the use of a 3 Tesla MR-compatible incubator because of its safety, easier, and faster handling (compared to standard imaging) and possibility to obtain high-quality MR images even in unstable patients.
Neural responses to negative outcomes predict success in community-based substance use treatment
Forster, Sarah E.; Finn, Peter R.; Brown, Joshua W.
2017-01-01
Background and aims Activation in some specific brain regions has demonstrated promise as prognostic indicators in substance dependent individuals (SDIs) but this issue has not yet been explored in SDIs attending typical of community-based treatment. We used a data-driven, exploratory approach to identify brain-based predictors of treatment outcome in a representative community sample of SDIs. The predictive utility of brain-based measures was evaluated against clinical indicators, cognitive-behavioral performance, and self-report assessments. Design Prospective clinical outcome design, evaluating baseline functional magnetic resonance imaging data from the Balloon Analogue Risk Task (BART) as a predictor of 3-month substance use treatment outcomes. Setting Community-based substance use programs in Bloomington, Indiana, USA. Participants Twenty-three SDIs (17 male, ages 18–43) in an intensive outpatient or residential treatment program; abstinent 1–4 weeks at baseline. Measurements Event-related brain response, BART performance, and self-report scores at treatment onset, substance use outcome measure (based on days of use) Findings Using voxel-level predictive modeling and leave-one-out cross-validation, an elevated response to unexpected negative feedback in bilateral amygdala and anterior hippocampus (Amyg/aHipp) at baseline successfully predicted greater substance use over the 3-month study interval (p ≤ 0.006, cluster-corrected). This effect was robust to inclusion of significant non-brain-based covariates. A larger response to negative feedback in bilateral Amyg/aHipp was also associated with faster reward-seeking responses after negative feedback (r(23) = −0.544, p = 0.007; r(23) = −0.588, p = 0.003). A model including Amyg/aHipp activation, faster reward-seeking after negative feedback, and significant self-report scores accounted for 45% of the variance in substance use outcomes in our sample. Conclusions An elevated response to unexpected negative feedback in bilateral amygdala and anterior hippocampus (Amyg/aHipp) appears to predict relapse to substance use in people attending community-based treatment. PMID:28029198
Evidence for size-selective mortality after the first summer of ocean growth by pink salmon
Moss, J.H.; Beauchamp, D.A.; Cross, A.D.; Myers, K.W.; Farley, Edward V.; Murphy, J.M.; Helle, J.H.
2005-01-01
Pink salmon Onchorhynchus gorbuscha with identifiable thermal otolith marks from Prince William Sound hatchery release groups during 2001 were used to test the hypothesis that faster-growing fish during their first summer in the ocean had higher survival rates than slower-growing fish. Marked juvenile pink salmon were sampled monthly in Prince William Sound and the Gulf of Alaska, and adults that survived to maturity were recovered at hatchery release sites the following year. Surviving fish exhibited significantly wider circuli spacing on the region of the scale formed during early marine residence than did juveniles collected at sea during their first ocean summer, indicating that marine survival after the first growing season was related to increases in early marine growth. At the same circuli, a significantly larger average scale radius for returning adults than for juveniles from the same hatchery would suggest that larger, faster-growing juveniles had a higher survival rate and that significant size-selective mortality occurred after the juveniles were sampled. Growth patterns inferred from intercirculi spacing on scales varied among hatchery release groups, suggesting that density-dependent processes differed among release groups and occurred across Prince William Sound and the coastal Gulf of Alaska. These observations support other studies that have found that larger, faster-growing fish are more likely to survive until maturity. ?? Copyright by the American Fisheries Society 2005.
Plasma treatment of Seeds: effect on growth, spores and bacterial charge
NASA Astrophysics Data System (ADS)
Ambrico, P. F.; Simek, M.; Morano, M.; Ambrico, M.; Minafra, A.; Prukner, V.; de Miccolis Angelini, R. M.; Trotti, P.
2016-09-01
We report on the effect of low temperature plasma treatment on tomato, basil and tobacco commercial seeds. Seeds were treated in filtered ambient air volume, surface and plasma jet DBD at atmospheric pressure Sterile agar substrate, supplemented with a nutrient and vitamin mixture, was used to allow seeds germination in sterilized sealed plastic containers. The seeds were stored in controlled environmental condition (T = 26C, cycle of 14hrs light/10hrs dark condition). Since all the procedure was performed under sterile conditions, only bacteria and fungi carried by seeds could grow. Plasma treatment significantly reduced the presence of bacterial contamination, while some fungi could resist at shortest exposures Seeds germination was then followed by time lapse photography in sterile water on 3MM Whatman paper in a closed container. The effect of plasma treatment was a faster germination time of seeds and emergence of cotyledons, able to start photosynthesis in seedlings.The plasma treated seeds were also sow in a soil/peat moss mixture. Plants were cultivated for about 40 days, showing that plasma induced a faster growth in length and weight with respect to untreated seeds.Furthermore the effect of plasma on seeds surface was studied by SEM imaging. We acknowledge `SELGE' (Puglia) and TACR (TA03010098).
Evolution of sperm structure and energetics in passerine birds
Rowe, Melissah; Laskemoen, Terje; Johnsen, Arild; Lifjeld, Jan T.
2013-01-01
Spermatozoa exhibit considerable interspecific variability in size and shape. Our understanding of the adaptive significance of this diversity, however, remains limited. Determining how variation in sperm structure translates into variation in sperm performance will contribute to our understanding of the evolutionary diversification of sperm form. Here, using data from passerine birds, we test the hypothesis that longer sperm swim faster because they have more available energy. We found that sperm with longer midpieces have higher levels of intracellular adenosine triphosphate (ATP), but that greater energy reserves do not translate into faster-swimming sperm. Additionally, we found that interspecific variation in sperm ATP concentration is not associated with the level of sperm competition faced by males. Finally, using Bayesian methods, we compared the evolutionary trajectories of sperm morphology and ATP content, and show that both traits have undergone directional evolutionary change. However, in contrast to recent suggestions in other taxa, we show that changes in ATP are unlikely to have preceded changes in morphology in passerine sperm. These results suggest that variable selective pressures are likely to have driven the evolution of sperm traits in different taxa, and highlight fundamental biological differences between taxa with internal and external fertilization, as well as those with and without sperm storage. PMID:23282997
In vitro and in vivo evaluation of capsaicin-loaded microemulsion for enhanced oral bioavailability.
Zhu, Yuan; Zhang, Jiajia; Zheng, Qianfeng; Wang, Miaomiao; Deng, Wenwen; Li, Qiang; Firempong, Caleb Kesse; Wang, Shengli; Tong, Shanshan; Xu, Ximing; Yu, Jiangnan
2015-10-01
Capsaicin, as a food additive, has attracted worldwide concern owing to its pungency and multiple pharmacological effects. However, poor water solubility and low bioavailability have limited its application. This study aims to develop a capsaicin-loaded microemulsion to enhance the oral bioavailability of the anti-neuropathic-pain component, capsaicin, which is poorly water soluble. In this study, the microemulsion consisting of Cremophor EL, ethanol, medium-chain triglycerides (oil phase) and water (external phase) was prepared and characterized (particle size, morphology, stability and encapsulation efficiency). The gastric mucosa irritation test of formulated capsaicin was performed in rats to evaluate its oral feasibility, followed by the pharmacokinetic study in vivo. Under these conditions, the encapsulated capsaicin revealed a faster capsaicin release in vitro coupled with a greater absorption in vivo when compared to the free capsaicin. The oral bioavailability of the formulated capsaicin-loaded microemulsions was 2.64-fold faster than that of free capsaicin. No significant irritation was observed on the mucosa from the pathological section of capsaicin-loaded microemulsion treated stomach. These results indicate that the developed microemulsion represents a safe and orally effective carrier for poorly soluble substances. The formulation could be used for clinical trials and expand the application of capsaicin. © 2014 Society of Chemical Industry.
General trends of dihedral conformational transitions in a globular protein.
Miao, Yinglong; Baudry, Jerome; Smith, Jeremy C; McCammon, J Andrew
2016-04-01
Dihedral conformational transitions are analyzed systematically in a model globular protein, cytochrome P450cam, to examine their structural and chemical dependences through combined conventional molecular dynamics (cMD), accelerated molecular dynamics (aMD) and adaptive biasing force (ABF) simulations. The aMD simulations are performed at two acceleration levels, using dihedral and dual boost, respectively. In comparison with cMD, aMD samples protein dihedral transitions approximately two times faster on average using dihedral boost, and ∼ 3.5 times faster using dual boost. In the protein backbone, significantly higher dihedral transition rates are observed in the bend, coil, and turn flexible regions, followed by the β bridge and β sheet, and then the helices. Moreover, protein side chains of greater length exhibit higher transition rates on average in the aMD-enhanced sampling. Side chains of the same length (particularly Nχ = 2) exhibit decreasing transition rates with residues when going from hydrophobic to polar, then charged and aromatic chemical types. The reduction of dihedral transition rates is found to be correlated with increasing energy barriers as identified through ABF free energy calculations. These general trends of dihedral conformational transitions provide important insights into the hierarchical dynamics and complex free energy landscapes of functional proteins. © 2016 Wiley Periodicals, Inc.
General trends of dihedral conformational transitions in a globular protein
Miao, Yinglong; Baudry, Jerome; Smith, Jeremy C.; ...
2016-02-15
In this paper, dihedral conformational transitions are analyzed systematically in a model globular protein, cytochrome P450cam, to examine their structural and chemical dependences through combined conventional molecular dynamics (cMD), accelerated molecular dynamics (aMD) and adaptive biasing force (ABF) simulations. The aMD simulations are performed at two acceleration levels, using dihedral and dual boost, respectively. In comparison with cMD, aMD samples protein dihedral transitions approximately two times faster on average using dihedral boost, and ~3.5 times faster using dual boost. In the protein backbone, significantly higher dihedral transition rates are observed in the bend, coil, and turn flexible regions, followed bymore » the β bridge and β sheet, and then the helices. Moreover, protein side chains of greater length exhibit higher transition rates on average in the aMD-enhanced sampling. Side chains of the same length (particularly Nχ = 2) exhibit decreasing transition rates with residues when going from hydrophobic to polar, then charged and aromatic chemical types. The reduction of dihedral transition rates is found to be correlated with increasing energy barriers as identified through ABF free energy calculations. In conclusion, these general trends of dihedral conformational transitions provide important insights into the hierarchical dynamics and complex free energy landscapes of functional proteins.« less
Lamas-Pinheiro, Ruben; Mitzman, Francesca; Miranda, Alice; Henriques-Coelho, Tiago; Estevão-Costa, José; Correia-Pinto, Jorge
2016-04-01
External compression is used for pectus carinatum (PC) treatment, but many patients are noncompliant. Costal cartilage resection (CCR) has been described as an alternative, but these approaches sacrifice the internal thoracic arteries (ITA). We aim to assess the feasibility of CCR sparing ITA comparing thoracoscopic and subcutaneous endoscopic approaches. Twelve pigs were used as models for surgical PC correction and randomized for 2 groups: thoracoscopy (T) and subcutaneous (subpectoralis) endoscopy (SP). In both groups, CCR from 3rd 4th and 5th ribs was performed avoiding ITA damage. ITA preservation was confirmed by Doppler-ultrasound as well as postmortem injection of methylene blue. Four persons evaluated the procedures being difficult, using a 6-item modified validated scale. In both techniques, the procedure was accomplished in all animals sparing ITAs. CCR was faster in T than in SP (49±5 vs. 65±16minutes, p<0.05). T was classified as easier than SP (p<0.001) with a significantly higher score for all items, especially better image and tissue handling. Sparing the ITAs during CCR for correction of PC is feasible in a porcine model and might be a goal in humans. The thoracoscopic approach allows for a faster and easier procedure. Copyright © 2016 Elsevier Inc. All rights reserved.
Optimal Padding for the Two-Dimensional Fast Fourier Transform
NASA Technical Reports Server (NTRS)
Dean, Bruce H.; Aronstein, David L.; Smith, Jeffrey S.
2011-01-01
One-dimensional Fast Fourier Transform (FFT) operations work fastest on grids whose size is divisible by a power of two. Because of this, padding grids (that are not already sized to a power of two) so that their size is the next highest power of two can speed up operations. While this works well for one-dimensional grids, it does not work well for two-dimensional grids. For a two-dimensional grid, there are certain pad sizes that work better than others. Therefore, the need exists to generalize a strategy for determining optimal pad sizes. There are three steps in the FFT algorithm. The first is to perform a one-dimensional transform on each row in the grid. The second step is to transpose the resulting matrix. The third step is to perform a one-dimensional transform on each row in the resulting grid. Steps one and three both benefit from padding the row to the next highest power of two, but the second step needs a novel approach. An algorithm was developed that struck a balance between optimizing the grid pad size with prime factors that are small (which are optimal for one-dimensional operations), and with prime factors that are large (which are optimal for two-dimensional operations). This algorithm optimizes based on average run times, and is not fine-tuned for any specific application. It increases the amount of times that processor-requested data is found in the set-associative processor cache. Cache retrievals are 4-10 times faster than conventional memory retrievals. The tested implementation of the algorithm resulted in faster execution times on all platforms tested, but with varying sized grids. This is because various computer architectures process commands differently. The test grid was 512 512. Using a 540 540 grid on a Pentium V processor, the code ran 30 percent faster. On a PowerPC, a 256x256 grid worked best. A Core2Duo computer preferred either a 1040x1040 (15 percent faster) or a 1008x1008 (30 percent faster) grid. There are many industries that can benefit from this algorithm, including optics, image-processing, signal-processing, and engineering applications.
Underwater near-infrared spectroscopy can measure training adaptations in adolescent swimmers
Parry, Dave; Cooper, Chris E.
2018-01-01
The development of an underwater near-infrared spectroscopy (uNIRS) device has enabled previously unattainable measurements of peripheral muscle hemodynamics and oxygenation to be taken within the natural aquatic environment. The purposes of this study were (i) to trial the use of uNIRS, in a real world training study, and (ii) to monitor the effects of a swim training program upon muscle oxygenation status in short distance swimming. A total of 14 junior club level swimmers completed a repeated swim sprint test before and after an eight week endurance training program. A waterproof, portable Near-Infrared Spectroscopy device was attached to the vastus lateralis. uNIRS successfully measured changes in muscle oxygenation and blood volume in all individuals; rapid sub-second time resolution of the device was able to demonstrate muscle oxygenation changes during the characteristic swim movements. Post training heart rate recovery and swim performance time were significantly improved. uNIRS data also showed significant changes. A larger rise in deoxyhemoglobin during individual sprints suggested training induced an increase in muscle oxygen extraction; a faster recovery time for muscle oxygenation suggested positive training induced changes and significant changes in muscle blood flow also occur. As a strong correlation was seen between an increased reoxygenation rate and an improved swim performance time, these findings support the use of uNIRS as a new performance analysis tool in swimming. PMID:29692951
Underwater near-infrared spectroscopy can measure training adaptations in adolescent swimmers.
Jones, Ben; Parry, Dave; Cooper, Chris E
2018-01-01
The development of an underwater near-infrared spectroscopy (uNIRS) device has enabled previously unattainable measurements of peripheral muscle hemodynamics and oxygenation to be taken within the natural aquatic environment. The purposes of this study were (i) to trial the use of uNIRS, in a real world training study, and (ii) to monitor the effects of a swim training program upon muscle oxygenation status in short distance swimming. A total of 14 junior club level swimmers completed a repeated swim sprint test before and after an eight week endurance training program. A waterproof, portable Near-Infrared Spectroscopy device was attached to the vastus lateralis . uNIRS successfully measured changes in muscle oxygenation and blood volume in all individuals; rapid sub-second time resolution of the device was able to demonstrate muscle oxygenation changes during the characteristic swim movements. Post training heart rate recovery and swim performance time were significantly improved. uNIRS data also showed significant changes. A larger rise in deoxyhemoglobin during individual sprints suggested training induced an increase in muscle oxygen extraction; a faster recovery time for muscle oxygenation suggested positive training induced changes and significant changes in muscle blood flow also occur. As a strong correlation was seen between an increased reoxygenation rate and an improved swim performance time, these findings support the use of uNIRS as a new performance analysis tool in swimming.
Galioto Wiedemann, R; Calvo, D; Meister, J; Spitznagel, M B
2014-12-01
Convergent evidence demonstrates that greater physical activity is associated with better cognitive functioning across many patient and healthy samples. However, this relationship has not been well examined among obese individuals and remains unclear. The present study examined the relationship between performance-based measures of attention/executive function and self-reported physical activity, as measured by the International Physical Activity Questionnaire, among lean (n = 36) and obese (n = 36) college students. Lean individuals performed better than obese individuals on measures of attention/executive function. No significant differences in self-reported physical activity emerged between weight groups. Higher self-reported physical activity was related to faster reaction time in lean individuals but slower reaction time in obese individuals. Additionally, in lean individuals, higher levels of self-reported physical activity were related to more errors on a task of speeded inhibitory control. The results are consistent with previous research demonstrating that greater physical activity is associated with faster attention and executive function abilities in healthy samples and highlight the importance of examining reaction time and accuracy indices separately on these measures. The lack of association among obese individuals may be due in part to inaccurate self-report in the current study. Additionally, the cognitive consequences of obesity may outweigh the benefits of physical activity in this group. Future work should investigate these associations in obese individuals using physical activity interventions, as well as a combination of self-report and objective measures to investigate discrepancies in reporting. © 2014 The Authors. Clinical Obesity © 2014 World Obesity.
Cutanda, Diana; Correa, Ángel; Sanabria, Daniel
2015-06-01
The present study investigated whether participants can develop temporal preparation driven by auditory isochronous rhythms when concurrently performing an auditory working memory (WM) task. In Experiment 1, participants had to respond to an auditory target presented after a regular or an irregular sequence of auditory stimuli while concurrently performing a Sternberg-type WM task. Results showed that participants responded faster after regular compared with irregular rhythms and that this effect was not affected by WM load; however, the lack of a significant main effect of WM load made it difficult to draw any conclusion regarding the influence of the dual-task manipulation in Experiment 1. In order to enhance dual-task interference, Experiment 2 combined the auditory rhythm procedure with an auditory N-Back task, which required WM updating (monitoring and coding of the information) and was presumably more demanding than the mere rehearsal of the WM task used in Experiment 1. Results now clearly showed dual-task interference effects (slower reaction times [RTs] in the high- vs. the low-load condition). However, such interference did not affect temporal preparation induced by rhythms, with faster RTs after regular than after irregular sequences in the high-load and low-load conditions. These results revealed that secondary tasks demanding memory updating, relative to tasks just demanding rehearsal, produced larger interference effects on overall RTs in the auditory rhythm task. Nevertheless, rhythm regularity exerted a strong temporal preparation effect that survived the interference of the WM task even when both tasks competed for processing resources within the auditory modality. (c) 2015 APA, all rights reserved).
NASA Astrophysics Data System (ADS)
Saponara, Sergio; Donati, Massimiliano; Fanucci, Luca; Odendahl, Maximilian; Leupers, Reiner; Errico, Walter
2013-02-01
The on-board data processing is a vital task for any satellite and spacecraft due to the importance of elaborate the sensing data before sending them to the Earth, in order to exploit effectively the bandwidth to the ground station. In the last years the amount of sensing data collected by scientific and commercial space missions has increased significantly, while the available downlink bandwidth is comparatively stable. The increasing demand of on-board real-time processing capabilities represents one of the critical issues in forthcoming European missions. Faster and faster signal and image processing algorithms are required to accomplish planetary observation, surveillance, Synthetic Aperture Radar imaging and telecommunications. The only available space-qualified Digital Signal Processor (DSP) free of International Traffic in Arms Regulations (ITAR) restrictions faces inadequate performance, thus the development of a next generation European DSP is well known to the space community. The DSPACE space-qualified DSP architecture fills the gap between the computational requirements and the available devices. It leverages a pipelined and massively parallel core based on the Very Long Instruction Word (VLIW) paradigm, with 64 registers and 8 operational units, along with cache memories, memory controllers and SpaceWire interfaces. Both the synthesizable VHDL and the software development tools are generated from the LISA high-level model. A Xilinx-XC7K325T FPGA is chosen to realize a compact PCI demonstrator board. Finally first synthesis results on CMOS standard cell technology (ASIC 180 nm) show an area of around 380 kgates and a peak performance of 1000 MIPS and 750 MFLOPS at 125MHz.
Szarpak, Lukasz; Truszewski, Zenon; Smereka, Jacek; Krajewski, Paweł; Fudalej, Marcin; Adamczyk, Piotr; Czyzewski, Lukasz
2016-05-01
Medical personnel may encounter difficulties in obtaining intravenous (IV) access during cardiac arrest. The 2015 American Heart Association guidelines and the 2015 European Resuscitation Council guidelines for cardiopulmonary resuscitation (CPR) suggest that rescuers establish intraosseous (IO) access if an IV line is not easily obtainable.The aim of the study was to compare the success rates of the IO proximal tibia and proximal humerus head access performed by paramedics using the New Intraosseous access device (NIO; Persys Medical, Houston, TX, USA) in an adult cadaver model during simulated CPR.In an interventional, randomized, crossover, single-center cadaver study, a semi-automatic spring-load driven NIO access device was investigated. In total, 84 paramedics with less than 5-year experience in Emergency Medical Service participated in the study. The trial was performed on 42 adult cadavers. In each cadaver, 2 IO accesses to the humerus head, and 2 IO accesses to the proximal tibia were obtained.The success rate of the first IO attempt was 89.3% (75/84) for tibial access, and 73.8% (62/84) for humeral access (P = 0.017). The procedure times were significantly faster for tibial access [16.8 (interquartile range, IQR, 15.1-19.9] s] than humeral access [26.7 (IQR, 22.1-30.9) s] (P < 0.001).Tibial IO access is easier and faster to put in place than humeral IO access. Humeral IO access can be an alternative method to tibial IO access. clinicaltrials.gov Identifier: NCT02700867.
Three-dimensional numerical simulation during laser processing of CFRP
NASA Astrophysics Data System (ADS)
Ohkubo, Tomomasa; Sato, Yuji; Matsunaga, Ei-ichi; Tsukamoto, Masahiro
2017-09-01
We performed three-dimensional numerical simulation about laser processing of carbon-fiber-reinforced plastic (CFRP) using OpenFOAM as libraries of finite volume method (FVM). Although a little theoretical or numerical studies about heat affected zone (HAZ) formation were performed, there is no research discussing how HAZ is generated considering time development about removal of each material. It is important to understand difference of removal speed of carbon fiber and resin in order to improve quality of cut surface of CFRP. We demonstrated how the carbon fiber and resin are removed by heat of ablation plume by our simulation. We found that carbon fiber is removed faster than resin at first stage because of the difference of thermal conductivity, and after that, the resin is removed faster because of its low combustion temperature. This result suggests the existence of optimal contacting time of the laser ablation and kerf of the target.
Chen, Feng; Wang, Shuang; Jiang, Xiaoqian; Ding, Sijie; Lu, Yao; Kim, Jihoon; Sahinalp, S. Cenk; Shimizu, Chisato; Burns, Jane C.; Wright, Victoria J.; Png, Eileen; Hibberd, Martin L.; Lloyd, David D.; Yang, Hai; Telenti, Amalio; Bloss, Cinnamon S.; Fox, Dov; Lauter, Kristin; Ohno-Machado, Lucila
2017-01-01
Abstract Motivation: We introduce PRINCESS, a privacy-preserving international collaboration framework for analyzing rare disease genetic data that are distributed across different continents. PRINCESS leverages Software Guard Extensions (SGX) and hardware for trustworthy computation. Unlike a traditional international collaboration model, where individual-level patient DNA are physically centralized at a single site, PRINCESS performs a secure and distributed computation over encrypted data, fulfilling institutional policies and regulations for protected health information. Results: To demonstrate PRINCESS’ performance and feasibility, we conducted a family-based allelic association study for Kawasaki Disease, with data hosted in three different continents. The experimental results show that PRINCESS provides secure and accurate analyses much faster than alternative solutions, such as homomorphic encryption and garbled circuits (over 40 000× faster). Availability and Implementation: https://github.com/achenfengb/PRINCESS_opensource Contact: shw070@ucsd.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:28065902
Abnormal Olfaction in Parkinson's Disease Is Related to Faster Disease Progression.
Cavaco, Sara; Gonçalves, Alexandra; Mendes, Alexandre; Vila-Chã, Nuno; Moreira, Inês; Fernandes, Joana; Damásio, Joana; Teixeira-Pinto, Armando; Bastos Lima, António
2015-01-01
A possible association between olfactory dysfunction and Parkinson's disease (PD) severity has been a topic of contention for the past 40 years. Conflicting reports may be partially explained by procedural differences in olfactory assessment and motor symptom evaluation. One hundred and sixty-six nondemented PD patients performed the Brief-Smell Identification Test and test scores below the estimated 20th percentile as a function of sex, age, and education (i.e., 80% specificity) were considered demographically abnormal. Patients underwent motor examination after 12 h without antiparkinsonian medication. Eighty-two percent of PD patients had abnormal olfaction. Abnormal performance on the Brief-Smell Identification Test was associated with higher disease severity (i.e., Hoehn and Yahr, Unified Parkinson's Disease Rating Scale-III, Freezing of Gait questionnaire, and levodopa equivalent dose), even when disease duration was taken into account. Abnormal olfaction in PD is associated with increased severity and faster disease progression.
A human performance evaluation of graphic symbol-design features.
Samet, M G; Geiselman, R E; Landee, B M
1982-06-01
16 subjects learned each of two tactical display symbol sets (conventional symbols and iconic symbols) in turn and were then shown a series of graphic displays containing various symbol configurations. For each display, the subject was asked questions corresponding to different behavioral processes relating to symbol use (identification, search, comparison, pattern recognition). The results indicated that: (a) conventional symbols yielded faster pattern-recognition performance than iconic symbols, and iconic symbols did not yield faster identification than conventional symbols, and (b) the portrayal of additional feature information (through the use of perimeter density or vector projection coding) slowed processing of the core symbol information in four tasks, but certain symbol-design features created less perceptual interference and had greater correspondence with the portrayal of specific tactical concepts than others. The results were discussed in terms of the complexities involved in the selection of symbol design features for use in graphic tactical displays.
Goal-driven modulation of stimulus-driven attentional capture in multiple-cue displays.
Richard, Christian M; Wright, Richard D; Ward, Lawrence M
2003-08-01
Six location-cuing experiments were conducted to examine the goal-driven control of attentional capture in multiple-cue displays. In most of the experiments, the cue display consisted of the simultaneous presentation of a red direct cue that was highly predictive of the target location (the unique cue) and three gray direct cues (the standard cues) that were not predictive of the location. The results indicated that although target responses were faster at all cued locations relative to uncued locations, they were significantly faster at the unique-cue location than at the standard-cue locations. Other results suggest that the faster responses produced by direct cues may be associated with two different components: an attention-related component that can be modulated by goal-driven factors and a nonattentional component that occurs in parallel at multiple direct-cue locations and is minimally affected by the same goal-driven factors.
Wilson, Mathew G; Lane, Andy M; Beedie, Chris J; Farooq, Abdulaziz
2012-01-01
The objective of the study is to examine the impact of accurate and inaccurate 'split-time' feedback upon a 10-mile time trial (TT) performance and to quantify power output into a practically meaningful unit of variation. Seven well-trained cyclists completed four randomised bouts of a 10-mile TT on a SRM™ cycle ergometer. TTs were performed with (1) accurate performance feedback, (2) without performance feedback, (3) and (4) false negative and false positive 'split-time' feedback showing performance 5% slower or 5% faster than actual performance. There were no significant differences in completion time, average power output, heart rate or blood lactate between the four feedback conditions. There were significantly lower (p < 0.001) average [Formula: see text] (ml min(-1)) and [Formula: see text] (l min(-1)) scores in the false positive (3,485 ± 596; 119 ± 33) and accurate (3,471 ± 513; 117 ± 22) feedback conditions compared to the false negative (3,753 ± 410; 127 ± 27) and blind (3,772 ± 378; 124 ± 21) feedback conditions. Cyclists spent a greater amount of time in a '20 watt zone' 10 W either side of average power in the negative feedback condition (fastest) than the accurate feedback (slowest) condition (39.3 vs. 32.2%, p < 0.05). There were no significant differences in the 10-mile TT performance time between accurate and inaccurate feedback conditions, despite significantly lower average [Formula: see text] and [Formula: see text] scores in the false positive and accurate feedback conditions. Additionally, cycling with a small variation in power output (10 W either side of average power) produced the fastest TT. Further psycho-physiological research should examine the mechanism(s) why lower [Formula: see text] and [Formula: see text] scores are observed when cycling in a false positive or accurate feedback condition compared to a false negative or blind feedback condition.
Feng, Chuan; Rozenblit, Jerzy W; Hamilton, Allan J
2010-11-01
Surgeons performing laparoscopic surgery have strong biases regarding the quality and nature of the laparoscopic video monitor display. In a comparative study, we used a unique computerized sensing and analysis system to evaluate the various types of monitors employed in laparoscopic surgery. We compared the impact of different types of monitor displays on an individual's performance of a laparoscopic training task which required the subject to move the instrument to a set of targets. Participants (varying from no laparoscopic experience to board-certified surgeons) were asked to perform the assigned task while using all three display systems, which were randomly assigned: a conventional laparoscopic monitor system (2D), a high-definition monitor system (HD), and a stereoscopic display (3D). The effects of monitor system on various performance parameters (total time consumed to finish the task, average speed, and movement economy) were analyzed by computer. Each of the subjects filled out a subjective questionnaire at the end of their training session. A total of 27 participants completed our study. Performance with the HD monitor was significantly slower than with either the 3D or 2D monitor (p < 0.0001). Movement economy with the HD monitor was significantly reduced compared with the 3D (p < 0.0004) or 2D (p < 0.0001) monitor. In terms of average time required to complete the task, performance with the 3D monitor was significantly faster than with the HD (p < 0.0001) or 2D (p < 0.0086) monitor. However, the HD system was the overwhelming favorite according to subjective evaluation. Computerized sensing and analysis is capable of quantitatively assessing the seemingly minor effect of monitor display on surgical training performance. The study demonstrates that, while users expressed a decided preference for HD systems, actual quantitative analysis indicates that HD monitors offer no statistically significant advantage and may even worsen performance compared with standard 2D or 3D laparoscopic monitors.
Okano, Masahiro; Shinya, Masahiro; Kudo, Kazutoshi
2017-01-01
In solo synchronization-continuation (SC) tasks, intertap intervals (ITI) are known to drift from the initial tempo. It has been demonstrated that people in paired and group contexts modulate their action timing unconsciously in various situations such as choice reaction tasks, rhythmic body sway, and hand clapping in concerts, which suggests the possibility that ITI drift is also affected by paired context. We conducted solo and paired SC tapping experiments with three tempos (75, 120, and 200 bpm) and examined whether tempo-keeping performance changed according to tempo and/or the number of players. Results indicated that those tapping in the paired conditions were faster, relative to those observed in the solo conditions, for all tempos. For the faster participants, the degree of ITI drift in the solo conditions was strongly correlated with that in the paired conditions. Regression analyses suggested that both faster and slower participants adapted their tap timing to that of their partners. A possible explanation for these results is that the participants reset the phase of their internal clocks according to the faster beat between their own tap and the partners’ tap. Our results indicated that paired context could bias the direction of ITI drift toward decreasing. PMID:28276461
Okano, Masahiro; Shinya, Masahiro; Kudo, Kazutoshi
2017-03-09
In solo synchronization-continuation (SC) tasks, intertap intervals (ITI) are known to drift from the initial tempo. It has been demonstrated that people in paired and group contexts modulate their action timing unconsciously in various situations such as choice reaction tasks, rhythmic body sway, and hand clapping in concerts, which suggests the possibility that ITI drift is also affected by paired context. We conducted solo and paired SC tapping experiments with three tempos (75, 120, and 200 bpm) and examined whether tempo-keeping performance changed according to tempo and/or the number of players. Results indicated that those tapping in the paired conditions were faster, relative to those observed in the solo conditions, for all tempos. For the faster participants, the degree of ITI drift in the solo conditions was strongly correlated with that in the paired conditions. Regression analyses suggested that both faster and slower participants adapted their tap timing to that of their partners. A possible explanation for these results is that the participants reset the phase of their internal clocks according to the faster beat between their own tap and the partners' tap. Our results indicated that paired context could bias the direction of ITI drift toward decreasing.
Size matters: bigger is faster.
Sereno, Sara C; O'Donnell, Patrick J; Sereno, Margaret E
2009-06-01
A largely unexplored aspect of lexical access in visual word recognition is "semantic size"--namely, the real-world size of an object to which a word refers. A total of 42 participants performed a lexical decision task on concrete nouns denoting either big or small objects (e.g., bookcase or teaspoon). Items were matched pairwise on relevant lexical dimensions. Participants' reaction times were reliably faster to semantically "big" versus "small" words. The results are discussed in terms of possible mechanisms, including more active representations for "big" words, due to the ecological importance attributed to large objects in the environment and the relative speed of neural responses to large objects.
Why Space Telescopes Are Amazing
NASA Technical Reports Server (NTRS)
Rigby, Jane R.
2012-01-01
One of humanity's best ideas has been to put telescopes in space. The dark stillness of space allows telescopes to perform much better than they can on even the darkest and clearest of Earth's mountaintops. In addition, from space we can detect colors of light, like X-rays and gamma rays, that are blocked by the Earth's atmosphere I'll talk about NASA's team of great observatories: the Hubble Space Telescope, Spitzer Space Telescope, and Chandra X-ray Observatory} and how they've worked together to answer key questions: When did the stars form? Is there really dark matter? Is the universe really expanding ever faster and faster?
NASA Astrophysics Data System (ADS)
Yoshimoto, Masahiro; Nakano, Toshiyuki; Komatani, Ryosuke; Kawahara, Hiroaki
2017-10-01
Automatic nuclear emulsion readout systems have seen remarkable progress since the original idea was developed almost 40 years ago. After the success of its full application to a large-scale neutrino experiment, OPERA, a much faster readout system, the hyper-track selector (HTS), has been developed. HTS, which has an extremely wide-field objective lens, reached a scanning speed of 4700 cm^2/h, which is nearly 100 times faster than the previous system and therefore strongly promotes many new experimental projects. We will describe the concept, specifications, system structure, and achieved performance in this paper.
Jones, Luke A; Allely, Clare S; Wearden, John H
2011-02-01
A series of experiments demonstrated that a 5-s train of clicks that have been shown in previous studies to increase the subjective duration of tones they precede (in a manner consistent with "speeding up" timing processes) could also have an effect on information-processing rate. Experiments used studies of simple and choice reaction time (Experiment 1), or mental arithmetic (Experiment 2). In general, preceding trials by clicks made response times significantly shorter than those for trials without clicks, but white noise had no effects on response times. Experiments 3 and 4 investigated the effects of clicks on performance on memory tasks, using variants of two classic experiments of cognitive psychology: Sperling's (1960) iconic memory task and Loftus, Johnson, and Shimamura's (1985) iconic masking task. In both experiments participants were able to recall or recognize significantly more information from stimuli preceded by clicks than those preceded by silence.
The Influence of Carbohydrate Mouth Rinse on Self-Selected Intermittent Running Performance.
Rollo, Ian; Homewood, George; Williams, Clyde; Carter, James; Goosey-Tolfrey, Vicky L
2015-12-01
This study investigated the influence of mouth rinsing a carbohydrate solution on self-selected intermittent variable-speed running performance. Eleven male amateur soccer players completed a modified version of the Loughborough Intermittent Shuttle Test (LIST) on 2 occasions separated by 1 wk. The modified LIST allowed the self-selection of running speeds during Block 6 of the protocol (75-90 min). Players rinsed and expectorated 25 ml of noncaloric placebo (PLA) or 10% maltodextrin solution (CHO) for 10 s, routinely during Block 6 of the LIST. Self-selected speeds during the walk and cruise phases of the LIST were similar between trials. Jogging speed was significantly faster during the CHO (11.3 ± 0.7 km · h(-1)) than during the PLA trial (10.5 ± 1.3 km · h(-1)) (p = .010); 15-m sprint speeds were not different between trials (PLA: 2.69 ± 0.18 s: CHO: 2.65 ± 0.13 s) (F(2, 10), p = .157), but significant benefits were observed for sprint distance covered (p = .024). The threshold for the smallest worthwhile change in sprint performance was set at 0.2 s. Inferential statistical analysis showed the chance that CHO mouth rinse was beneficial, negligible, or detrimental to repeated sprint performance was 86%, 10%, and 4%, respectively. In conclusion, mouth rinsing and expectorating a 10% maltodextrin solution was associated with a significant increase in self-selected jogging speed. Repeated 15-m sprint performance was also 86% likely to benefit from routinely mouth rinsing a carbohydrate solution in comparison with a taste-matched placebo.
Yamagishi, Hatsushi; Koike, Tomoyuki; Ohara, Shuichi; Horii, Toru; Kikuchi, Ryousuke; Kobayashi, Shigeyuki; Abe, Yasuhiko; Iijima, Katsunori; Imatani, Akira; Suzuki, Kaori; Hishinuma, Takanori; Goto, Junichi; Shimosegawa, Tooru
2008-01-01
AIM: To compare rabeprazole (RPZ; 10 mg) with Lansoprazole orally disintegrating tablets (LPZ; 30 mg OD) in terms of antisecretory activity and blood drug concentration after a single dose. METHODS: Eight H pylori-negative cytochrome P450 (CYP) 2C19 extensive metabolizers were assigned to receive a single oral dose of RPZ 10 mg or LPZ 30 mg OD. Twelve hour intragastric pH monitoring was performed on the day of treatment. Blood samples were also collected after the administration of each drug. RESULTS: LPZ 30 mg OD induced a significantly earlier rise in blood drug concentration than RPZ 10 mg; consequently, LPZ 30 mg OD induced a significantly earlier rise in median pH in the third and fourth hours of the study. CONCLUSION: In H pylori-negative CYP2C19 extensive metabolizers, LPZ 30 mg OD induced a significantly faster inhibition of gastric acid secretion than RPZ 10 mg. PMID:18395905
Alexander, Michael B; Hodges, Theresa K; Wescott, Daniel J; Aitkenhead-Peterson, Jacqueline A
2016-05-01
Despite technological advances, human remains detection (HRD) dogs still remain one of the best tools for locating clandestine graves. However, soil texture may affect the escape of decomposition gases and therefore the effectiveness of HDR dogs. Six nationally credentialed HRD dogs (three HRD only and three cross-trained) were evaluated on novel buried human remains in contrasting soils, a clayey and a sandy soil. Search time and accuracy were compared for the clayey soil and sandy soil to assess odor location difficulty. Sandy soil (p < 0.001) yielded significantly faster trained response times, but no significant differences were found in performance accuracy between soil textures or training method. Results indicate soil texture may be significant factor in odor detection difficulty. Prior knowledge of soil texture and moisture may be useful for search management and planning. Appropriate adjustments to search segment sizes, sweep widths and search time allotment depending on soil texture may optimize successful detection. © 2016 American Academy of Forensic Sciences.
Gonçalves, M; Alves, M M; Correia, J P; Marques, I P
2008-11-01
Electrochemical treatment of oleate using RuO2 and IrO2 type dimensionally stable anodes in alkaline medium was performed to develop a feasible anaerobic pre-treatment of fatty effluents. The results showed that the pre-treated solutions over RuO2 were faster degraded by anaerobic consortium than the raw oleate solutions or the electrolysed solutions using IrO2. In batch experiments carried out with pre-treated solutions over RuO2 (100-500mg/L), no lag phases were observed before the methane production onset. On the other hand, raw oleate and pre-treated oleate over IrO2 had originated lag phases of 0-140 and 0-210h, respectively. This study demonstrated that it is advantageous to apply the electrochemical treatment carried out on the RuO2 type DSA in order to achieve a faster biodegradation of lipid-containing effluent and consequently to obtain a faster methane production.
Faster sequence homology searches by clustering subsequences.
Suzuki, Shuji; Kakuta, Masanori; Ishida, Takashi; Akiyama, Yutaka
2015-04-15
Sequence homology searches are used in various fields. New sequencing technologies produce huge amounts of sequence data, which continuously increase the size of sequence databases. As a result, homology searches require large amounts of computational time, especially for metagenomic analysis. We developed a fast homology search method based on database subsequence clustering, and implemented it as GHOSTZ. This method clusters similar subsequences from a database to perform an efficient seed search and ungapped extension by reducing alignment candidates based on triangle inequality. The database subsequence clustering technique achieved an ∼2-fold increase in speed without a large decrease in search sensitivity. When we measured with metagenomic data, GHOSTZ is ∼2.2-2.8 times faster than RAPSearch and is ∼185-261 times faster than BLASTX. The source code is freely available for download at http://www.bi.cs.titech.ac.jp/ghostz/ akiyama@cs.titech.ac.jp Supplementary data are available at Bioinformatics online. © The Author 2014. Published by Oxford University Press.
High pressure study on molecular mobility of leucrose
NASA Astrophysics Data System (ADS)
Kaminski, K.; Kaminska, E.; Hensel-Bielowka, S.; Pawlus, S.; Paluch, M.; Ziolo, J.
2008-08-01
Broadband dielectric measurements on leucrose were performed under ambient and high pressure. We showed that in this disaccharide, there are two secondary relaxation modes, a slower one sensitive to pressure and a faster one that is not. This finding clearly indicates that the faster secondary relaxation originates from the intramolecular motion. This conclusion contradicted previous interpretations of this mode observed for trehalose and maltitol, systems very closely related to leucrose. In addition, pressure sensitivity of the slower relaxation confirms our recent interpretation about the character of this process. Furthermore, we discovered that unlike the faster relaxation, the slower secondary relaxation is sensitive to the thermodynamic history of measurements. Finally, monitoring the changes in maximum loss of the slower secondary relaxation measured at the same pressure and temperature conditions for glasses obtained via different thermodynamic routes enabled us to draw a conclusion about the density of the formed glasses. Our observations may be helpful in establishing a new method of suppressing crystallization of amorphous drugs.
Yan, Xuedong; Zhang, Xinran; Zhang, Yuting; Li, Xiaomeng; Yang, Zhuo
2016-01-01
The intersection field of view (IFOV) indicates an extent that the visual information can be observed by drivers. It has been found that further enhancing IFOV can significantly improve emergent collision avoidance performance at intersections, such as faster brake reaction time, smaller deceleration rate, and lower traffic crash involvement risk. However, it is not known how IFOV affects drivers’ eye movements, visual attention and the relationship between visual searching and traffic safety. In this study, a driving simulation experiment was conducted to uncover the changes in drivers’ visual performance during the collision avoidance process as a function of different field of views at an intersection by using an eye tracking system. The experimental results showed that drivers’ ability in identifying the potential hazard in terms of visual searching was significantly affected by different IFOV conditions. As the IFOVs increased, drivers had longer gaze duration (GD) and more number of gazes (NG) in the intersection surrounding areas and paid more visual attention to capture critical visual information on the emerging conflict vehicle, thus leading to a better collision avoidance performance and a lower crash risk. It was also found that female drivers had a better visual performance and a lower crash rate than male drivers. From the perspective of drivers’ visual performance, the results strengthened the evidence that further increasing intersection sight distance standards should be encouraged for enhancing traffic safety. PMID:27716824
Twin Cities Metro Freight Initiative : Performance Management Framework
DOT National Transportation Integrated Search
2011-10-31
As the demand for freight and passenger transportation continues to increase faster than our ability to manage current transportation facilities or provide new ones, we can expect increased congestion and lower mobility, as well as degradation of saf...
NASA Astrophysics Data System (ADS)
Furubayashi, T.; Bansho, Y.; Motooka, D.; Nakamura, S.; Ichihashi, N.
2017-07-01
We performed coevolution of artificial RNA self-replicators and parasitic replicators in microdroplets. We observed evolutionary arms-races with oscillating population dynamics and faster evolution of self-replicators caused by parasitic replicators.
Predicting Airport Screening Officers' Visual Search Competency With a Rapid Assessment.
Mitroff, Stephen R; Ericson, Justin M; Sharpe, Benjamin
2018-03-01
Objective The study's objective was to assess a new personnel selection and assessment tool for aviation security screeners. A mobile app was modified to create a tool, and the question was whether it could predict professional screeners' on-job performance. Background A variety of professions (airport security, radiology, the military, etc.) rely on visual search performance-being able to detect targets. Given the importance of such professions, it is necessary to maximize performance, and one means to do so is to select individuals who excel at visual search. A critical question is whether it is possible to predict search competency within a professional search environment. Method Professional searchers from the USA Transportation Security Administration (TSA) completed a rapid assessment on a tablet-based X-ray simulator (XRAY Screener, derived from the mobile technology app Airport Scanner; Kedlin Company). The assessment contained 72 trials that were simulated X-ray images of bags. Participants searched for prohibited items and tapped on them with their finger. Results Performance on the assessment significantly related to on-job performance measures for the TSA officers such that those who were better XRAY Screener performers were both more accurate and faster at the actual airport checkpoint. Conclusion XRAY Screener successfully predicted on-job performance for professional aviation security officers. While questions remain about the underlying cognitive mechanisms, this quick assessment was found to significantly predict on-job success for a task that relies on visual search performance. Application It may be possible to quickly assess an individual's visual search competency, which could help organizations select new hires and assess their current workforce.
Smith, A M; Sim, F H; Smith, H C; Stuart, M J; Laskowski, E R
1998-01-01
To determine the relationship between psychologic, situational, and physiologic variables and on-ice performance of youth hockey goalkeepers. This study was structured to identify relationships and predictors of goalie performance. Because athletes playing solo positions in team sports have not been analyzed in depth in terms of precompetition anxiety and because goalkeeper performance is critical to game outcome, we undertook a study of 43 goalies at a hockey camp. These goalies completed psychometric inventories to assess trait and state anxiety, confidence, life stress, and social support. Holter monitors measured heart rate while the goalies rotated through on-ice stations. Goalies were videotaped at the puck-shooting machine station, and performance (percent saves) was calculated. Trait (somatic) anxiety and positive mood state (ability to share) had different but significant relationships with on-ice performance. Heart rates ranged from 88 to 208 beats/min at the on-ice stations. Mean heart rate for older goalies (14 to 18 years of age) was 164 beats/min at the puck-shooting machine and 176 beats/min at other stations such as the slap-shot station. Older goalies performed well at a high level of arousal. Better performing goalies were more experienced, had faster heart rates "in the net," and had lower scores on all measures of anxiety.
RAPID SEPARATION METHOD FOR EMERGENCY WATER AND URINE SAMPLES
DOE Office of Scientific and Technical Information (OSTI.GOV)
Maxwell, S.; Culligan, B.
2008-08-27
The Savannah River Site Environmental Bioassay Lab participated in the 2008 NRIP Emergency Response program administered by the National Institute for Standards and Technology (NIST) in May, 2008. A new rapid column separation method was used for analysis of actinides and {sup 90}Sr the NRIP 2008 emergency water and urine samples. Significant method improvements were applied to reduce analytical times. As a result, much faster analysis times were achieved, less than 3 hours for determination of {sup 90}Sr and 3-4 hours for actinides. This represents a 25%-33% improvement in analysis times from NRIP 2007 and a {approx}100% improvement compared tomore » NRIP 2006 report times. Column flow rates were increased by a factor of two, with no significant adverse impact on the method performance. Larger sample aliquots, shorter count times, faster cerium fluoride microprecipitation and streamlined calcium phosphate precipitation were also employed. Based on initial feedback from NIST, the SRS Environmental Bioassay Lab had the most rapid analysis times for actinides and {sup 90}Sr analyses for NRIP 2008 emergency urine samples. High levels of potential matrix interferences may be present in emergency samples and rugged methods are essential. Extremely high levels of {sup 210}Po were found to have an adverse effect on the uranium results for the NRIP-08 urine samples, while uranium results for NRIP-08 water samples were not affected. This problem, which was not observed for NRIP-06 or NRIP-07 urine samples, was resolved by using an enhanced {sup 210}Po removal step, which will be described.« less
Settling behavior of unpurified Cryptosporidium oocysts in laboratory settling columns.
Young, Pamela L; Komisar, Simeon J
2005-04-15
The settling behavior of fresh and aged unpurified oocysts was examined in settling column suspensions with varied ionic strengths and concentrations of calcium and magnesium. Independent measurements of the size and density of unpurified oocysts were performed to determine a theoretical settling velocity for the test populations. Viability of the oocysts was assessed using a dye permeability assay. Latex microspheres were included to provide a standard by which to assess the settling conditions in the columns. Mean settling velocities for viable oocysts measured in this work were faster than predicted and faster than measured for purified oocysts in other work: 1.31 (+/-0.21) microm/s for viable oocysts from populations having a low percentage of viable oocysts and 1.05 (+/-0.20) microm/s for viable oocysts from populations with a high percentage of viable oocysts. Results were attributed to the higher than previously reported densities measured for oocysts in this study and the presence of fecal material, which allowed opportunity for particle agglomeration. Settling velocity of oocysts was significantly related to the viability of the population, particle concentration, ionic strength, and presence of calcium and magnesium in the suspending medium. Behavior of the latex microspheres was not entirely predictive of the behavior of the oocysts under the test conditions. Viable oocysts may have a greater probability of settling than previously assumed; however, nonviable, and especially nonintact, oocysts have the potential to be significantly transported in water. This work underscores the importance of assessing the viability of oocysts to predict their response to environmental and experimental conditions.
Medović, Rasa; Igrutinović, Zoran; Radojević-Marjanović, Ruzica; Marković, Slavica; Rasković, Zorica; Simović, Aleksandra; Tanasković-Nestorović, Jelena; Radovanović, Marija; VuIetić, Blijana
2016-01-01
Infective mononucleosis is most commonly caused by Epstein-Barr virus (EBV), and in smaller percentage by cytomegalovirus (CMV). The aim of this paper was to determine the clinical and laboratory differences between EBV and CMV infectious mononucleosis in children. Cohort retrospective analytical research was conducted. We used data from medical history in six years period and monitored anamnestic data, frequency of inspection and palpation obtained data during physical examination, several laboratory tests, abdomen ultrasonography examination finding and emergence of disease complications. Statistical processing of data has been performed using SPSS 20. Total number of examined children was 137, out of which 85.4% were with EBV and 14.6% with CMV infection. Affected children were most commonly younger than eight years. Boys were affected more often. There was no difference in frequency of high temperature, sore throat, bad breath, and respiratory symptomatology between examined children. Differences were discovered in frequency of stomachaches, eyelid swelling, skin rash and fatigue. Differences were not proven in the frequency of angina, lymphadenopathy and splenohepatomegaly between the groups. Values of transaminases and lactic dehydrogenases significantly decreased after seven days of hospitalization in both groups. In children with EBV, values of transaminases declined faster than in children with CMV. Anemia and bacterial superinfection of pharynx were most common disease complications. Thrombocytopenia was more common in children with CMV infection. Average duration of hospitalization was 6.7 days. In children with CMV abdominal pain, eyelid swelling, skin rash, fatigue and thrombocytopenia were more common. In children with EBV values of transaminases declined significantly faster.
Transcriptome sequencing reveals genome-wide variation in molecular evolutionary rate among ferns.
Grusz, Amanda L; Rothfels, Carl J; Schuettpelz, Eric
2016-08-30
Transcriptomics in non-model plant systems has recently reached a point where the examination of nuclear genome-wide patterns in understudied groups is an achievable reality. This progress is especially notable in evolutionary studies of ferns, for which molecular resources to date have been derived primarily from the plastid genome. Here, we utilize transcriptome data in the first genome-wide comparative study of molecular evolutionary rate in ferns. We focus on the ecologically diverse family Pteridaceae, which comprises about 10 % of fern diversity and includes the enigmatic vittarioid ferns-an epiphytic, tropical lineage known for dramatically reduced morphologies and radically elongated phylogenetic branch lengths. Using expressed sequence data for 2091 loci, we perform pairwise comparisons of molecular evolutionary rate among 12 species spanning the three largest clades in the family and ask whether previously documented heterogeneity in plastid substitution rates is reflected in their nuclear genomes. We then inquire whether variation in evolutionary rate is being shaped by genes belonging to specific functional categories and test for differential patterns of selection. We find significant, genome-wide differences in evolutionary rate for vittarioid ferns relative to all other lineages within the Pteridaceae, but we recover few significant correlations between faster/slower vittarioid loci and known functional gene categories. We demonstrate that the faster rates characteristic of the vittarioid ferns are likely not driven by positive selection, nor are they unique to any particular type of nucleotide substitution. Our results reinforce recently reviewed mechanisms hypothesized to shape molecular evolutionary rates in vittarioid ferns and provide novel insight into substitution rate variation both within and among fern nuclear genomes.
An insulin resistance associated neural correlate of impulsivity in type 2 diabetes mellitus
Eckstrand, Kristen L.; Mummareddy, Nishit; Kang, Hakmook; Cowan, Ronald; Zhou, Minchun; Zald, David; Silver, Heidi J.; Niswender, Kevin D.; Avison, Malcolm J.
2017-01-01
Central insulin resistance (IR) influences striatal dopamine (DA) tone, an important determinant of behavioral self-regulation. We hypothesized that an association exists between the degree of peripheral IR and impulse control, mediated by the impact of IR on brain circuits controlling the speed of executing “go” and/or “stop” responses. We measured brain activation and associated performance on a stop signal task (SST) in obese adults with type 2 diabetes (age, 48.1 ± 6.9 yrs (mean ± SD); BMI, 36.5 ± 4.0 kg/m2; HOMA-IR, 7.2 ± 4.1; 12 male, 18 female). Increasing IR, but not BMI, was a predictor of shorter critical stop signal delay (cSSD), a measure of the time window during which a go response can be successfully countermanded (R2 = 0.12). This decline was explained by an IR-associated increase in go speed (R2 = 0.13) with little impact of IR or BMI on stop speed. Greater striatal fMRI activation contrast in stop error (SE) compared with stop success (SS) trials (CONSE>SS) was a significant predictor of faster go speeds (R2 = 0.33, p = 0.002), and was itself predicted by greater IR (CONSE>SS vs HOMA-IR: R2 = 0.10, p = 0.04). Furthermore, this impact of IR on striatal activation was a significant mediator of the faster go speeds and greater impulsivity observed with greater IR. These findings suggest a neural mechanism by which IR may increase impulsivity and degrade behavioral self-regulation. PMID:29228027
Guseh, Stephanie H; Chen, Xiaodong P; Johnson, Natasha R
2015-12-26
The purpose of this pilot study was to examine our hypothesis that enriching workplace emotional intelligence through resident coaches could improve third-year medical students' adaptability and proactivity on the Obstetrics and Gynecology clerkship. An observational pilot study was conducted in a teaching hospital. Fourteen 3rd year medical students from two cohorts of clerkships were randomly divided into two groups, and equally assigned to trained resident coaches and untrained resident coaches. Data was collected through onsite naturalistic observation of students' adaptability and proactivity in clinical settings using a checklist with a 4-point Likert scale (1=poor to 4=excellent). Wilcoxon rank-sum test was used to compare the differences between these two groups. A total of 280 data points were collected through onsite observations conducted by investigators. All (n=14) students' adaptability and proactivity performance significantly improved from an average of 3.04 to 3.45 (p=0.014) over 6-week clerkship. Overall, students with trained resident coaches adapted significantly faster and were more proactive in the obstetrics and gynecology clinical setting than the students with untrained coaches (3.31 vs. 3.24, p=0.019). Findings from our pilot study supported our hypothesis that enriching workplace emotional intelligence knowledge through resident coaches was able to help medical students adapt into obstetrics and gynecology clinical settings faster and become more proactive in learning. Clerkship programs can incorporate the concept of a resident coach in their curriculum to help bridge medical students into clinical settings and to help them engage in self-directed learning throughout the rotation.
Werner, Joseph G; Castellon-Larios, Karina; Thongrong, Cattleya; Knudsen, Bodo E; Lowery, Deborah S; Antor, Maria A; Bergese, Sergio Daniel
2015-01-01
We compared the effect of desflurane and sevoflurane on anesthesia recovery time in patients undergoing urological cystoscopic surgery. The Short Orientation-Memory-Concentration Test (SOMCT) measured and compared cognitive impairment between groups and coughing was assessed throughout the anesthetic. This investigation included 75 ambulatory patients. Patients were randomized to receive either desflurane or sevoflurane. Inhalational anesthetics were discontinued after removal of the cystoscope and once repositioning of the patient was final. Coughing assessment and awakening time from anesthesia were assessed by a blinded observer. Statistical analysis was performed by using t-test for parametric variables and Mann-Whitney U test for non-parametric variables. The primary endpoint, mean time to eye-opening, was 5.0 ± 2.5 min for desflurane and 7.9 ± 4.1 min for sevoflurane (p < 0.001). There were no significant differences in time to SOMCT recovery (p = 0.109), overall time spent in the post-anesthesia care unit (PACU) (p = 0.924) or time to discharge (p = 0.363). Median time until readiness for discharge was 9 min in the desflurane group, while the sevoflurane group had a median time of 20 min (p = 0.020). The overall incidence of coughing during the perioperative period was significantly higher in the desflurane (p = 0.030). We re-confirmed that patients receiving desflurane had a faster emergence and met the criteria to be discharged from the PACU earlier. No difference was found in time to return to baseline cognition between desflurane and sevoflurane.
Conceptual question response times in Peer Instruction classrooms
NASA Astrophysics Data System (ADS)
Miller, Kelly; Lasry, Nathaniel; Lukoff, Brian; Schell, Julie; Mazur, Eric
2014-12-01
Classroom response systems are widely used in interactive teaching environments as a way to engage students by asking them questions. Previous research on the time taken by students to respond to conceptual questions has yielded insights on how students think and change conceptions. We measure the amount of time students take to respond to in-class, conceptual questions [ConcepTests (CTs)] in two introductory physics courses taught using Peer Instruction and use item response theory to determine the difficulty of the CTs. We examine response time differences between correct and incorrect answers both before and after the peer discussion for CTs of varying difficulty. We also determine the relationship between response time and student performance on a standardized test of incoming physics knowledge, precourse self-efficacy, and gender. Our data reveal three results of interest. First, response time for correct answers is significantly faster than for incorrect answers, both before and after peer discussion, especially for easy CTs. Second, students with greater incoming physics knowledge and higher self-efficacy respond faster in both rounds. Third, there is no gender difference in response rate after controlling for incoming physics knowledge scores, although males register significantly more attempts before committing to a final answer than do female students. These results provide insight into effective CT pacing during Peer Instruction. In particular, in order to maintain a pace that keeps everyone engaged, students should not be given too much time to respond. When around 80% of the answers are in, the ratio of correct to incorrect responses rapidly approaches levels indicating random guessing and instructors should close the poll.
Guseh, Stephanie H.; Chen, Xiaodong P.
2015-01-01
Objectives The purpose of this pilot study was to examine our hypothesis that enriching workplace emotional intelligence through resident coaches could improve third-year medical students’ adaptability and proactivity on the Obstetrics and Gynecology clerkship. Methods An observational pilot study was conducted in a teaching hospital. Fourteen 3rd year medical students from two cohorts of clerkships were randomly divided into two groups, and equally assigned to trained resident coaches and untrained resident coaches. Data was collected through onsite naturalistic observation of students’ adaptability and proactivity in clinical settings using a checklist with a 4-point Likert scale (1=poor to 4=excellent). Wilcoxon rank-sum test was used to compare the differences between these two groups. Results A total of 280 data points were collected through onsite observations conducted by investigators. All (n=14) students’ adaptability and proactivity performance significantly improved from an average of 3.04 to 3.45 (p=0.014) over 6-week clerkship. Overall, students with trained resident coaches adapted significantly faster and were more proactive in the obstetrics and gynecology clinical setting than the students with untrained coaches (3.31 vs. 3.24, p=0.019). Conclusions Findings from our pilot study supported our hypothesis that enriching workplace emotional intelligence knowledge through resident coaches was able to help medical students adapt into obstetrics and gynecology clinical settings faster and become more proactive in learning. Clerkship programs can incorporate the concept of a resident coach in their curriculum to help bridge medical students into clinical settings and to help them engage in self-directed learning throughout the rotation. PMID:26708233
Impact of metabolic syndrome on progression of aortic stenosis: influence of age and statin therapy.
Capoulade, Romain; Clavel, Marie-Annick; Dumesnil, Jean G; Chan, Kwan L; Teo, Koon K; Tam, James W; Côté, Nancy; Mathieu, Patrick; Després, Jean-Pierre; Pibarot, Philippe
2012-07-17
The aims of this study were to examine prospectively the relationship between metabolic syndrome (MetS) and aortic stenosis (AS) progression and to evaluate the effect of age and statin therapy on AS progression in patients with or without MetS. Despite the clear benefits of statin therapy in primary and secondary coronary heart disease prevention, several recent randomized trials have failed to demonstrate any significant effect of this class of drugs on the progression of AS. Previous retrospective studies have reported an association between MetS and faster AS progression. This predefined substudy included 243 of the 269 patients enrolled in the ASTRONOMER (AS Progression Observation: Measuring Effects of Rosuvastatin) trial. Follow-up was 3.4 ± 1.3 years. AS progression rate was measured by calculating the annualized increase in peak aortic jet velocity measured by Doppler echocardiography. Patients with MetS (27%) had faster stenosis progression (+0.25 ± 0.21 m/s/year vs. +0.19 ± 0.19 m/s/year, p = 0.03). Predictors of faster AS progression in multivariate analysis were older age (p = 0.01), higher degree of valve calcification (p = 0.01), higher peak aortic jet velocity at baseline (p = 0.007), and MetS (p = 0.005). Impact of MetS on AS progression was most significant in younger (< 57 years) patients (MetS: +0.24 ± 0.19 m/s/year vs. no MetS: +0.13 ± 0.18 m/s/year, p = 0.008) and among patients receiving statin therapy (+0.27 ± 0.23 m/s/year vs. +0.19 ± 0.18 m/s/year, p = 0.045). In multivariate analysis, the MetS-age interaction was significant (p = 0.01), but the MetS-statin use interaction was not. MetS was found to be a powerful and independent predictor of faster AS progression, with more pronounced impact in younger patients. These findings emphasize the importance of routinely identifying and treating MetS in AS patients. The apparent faster stenosis progression in the subset of normocholesterolemic patients with MetS receiving the statin will need to be confirmed by future studies. Copyright © 2012 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Fan, Yu; Kong, Gaiqing; Meng, Yisen; Tan, Shutao; Wei, Kunlin; Zhang, Qian; Jin, Jie
2014-11-01
Flank position is extensively used in retroperitoneoscopic urological practice. Most surgeons follow the patients' position in open approaches. However, surgical ergonomics of the conventional position in the retroperitoneoscopic surgery is poor. We introduce a modified position and evaluated task performance and surgical ergonomics of both positions with simulated surgical tasks. Twenty-one novice surgeons were recruited to perform four tasks: bead transfer, ring transfer, continuous suturing, and cutting a circle. The conventional position was simulated by setting an endo-surgical simulator parallel to the long axis of a surgical desk. The modified position was simulated by rotating the simulator 30° with respect to the long axis of the desk. The outcome measurements include task performance measures, kinematic measures for body alignment, surface electromyography, relative loading between feet, and subjective ratings of fatigue. We observed significant improvements in both task performance and surgical ergonomics parameters under the modified position. For all four tasks, subjects finished tasks faster with higher accuracy (p < 0.005 or < 0.001). For ergonomics part: (1) The angle between the upper body and the head was decreased by 7.4 ± 1.7°; (2) The EMG amplitude collected from shoulders and left lumber was significantly lower (p < 0.05); (3) Relative loading between feet was more balanced (p < 0.001); (4) Manual-action muscles and postural muscles are rated less fatiguing according to the questionnaire (p < 0.05). Conventional position of patient in retroperitoneoscopic upper urinary tract surgery is associated with poor surgical ergonomics. With a simulated surgery, we demonstrated that our modified position could significantly improve task performance and surgical ergonomics. Further studies are still warranted to validate these benefits for both patients and surgeons.
Lockhart, Tamara L; Jamieson, Christopher P; Steinman, Alan M; Giesbrecht, Gordon G
2005-10-01
Personal floatation devices (PFDs) differ in whether they maintain the head out of the water or allow the dorsum of the head to be immersed. Partial head submersion may hasten systemic cooling, incapacitation, and death in cold water. Six healthy male volunteers (mean age = 26.8 yr; height = 184 cm; weight = 81 kg; body fat = 20%) were immersed in 10 degrees C water for 65 min, or until core temperature = 34 degrees C, under three conditions: PFD#1 maintained the head and upper chest out of the water; PFD#2 allowed the dorsal head and whole body to be immersed; and an insulated drysuit (control) allowed the dorsal head to be immersed. Mental performance tests included: logic reasoning test; Stroop word-color test; digit symbol coding; backward digit span; and paced auditory serial addition test (PASAT). Core cooling was significantly faster for PFD#2 (2.8 +/- 1.6 degrees C x h(-1)) than for PFD#1 (1.5 +/- 0.7 degrees C x h(-1)) or for the drysuit (0.4 +/- 0.2 degrees C x h(-1)). Although no statistically significant effects on cognitive performance were noted for the individual PFDs and drysuit, when analyzed as a group, four of the tests of cognitive performance (Stroop word-color, digit symbol coding, backward digit span, and PASAT) showed significant correlations between decreasing core temperature to 34 degrees C and diminished cognitive performance. Performance in more complicated mental tasks was adversely affected as core temperature decreased to 34 degrees C. The PFD that kept the head and upper chest out of the water preserved body heat and mental performance better than the PFD that produced horizontal flotation.
ERIC Educational Resources Information Center
Bush, Ellen S.; Dweck, Carol S.
1975-01-01
Children classified as high-anxious reflective in cognitive style were found to perform as well on speeded tasks as low-anxious reflective children and both groups were found to be faster and more accurate than impulsive children. This suggests redefining cognitive style to stress the strategies used rather than predispositions for particular…
Rhinoscintigraphic analysis of nasal mucociliary function in patients with Bell's palsy.
Boynuegri, S; Ozer, S; Peksoy, I; Acikalin, A; Tuna, E Ü; Dursun, E; Eryilmaz, A
2016-01-01
Mucociliary transport (MCT) is an important defense mechanism of the respiratory tract. One of the major factors determining MCT is the ciliary activity of the respiratory epithelium. Rhinoscintigraphy is the most commonly used method for the analysis of mucociliary activity. The aim of this study was to investigate the effect of facial paralysis on the nasal mucociliary clearance. This study included 38 Bell's palsy patients as the study group and 10 subjects without any history of paranasal sinus disease or facial paralysis as the control group. A drop of technetium 99m-labeled macroaggregated albumin (Tc-99m MAA) was placed posterior to the head of the inferior turbinate and followed with a gamma camera. MCT rate was measured as the velocity of Tc-99m MAA drop. The mean MCT rate was 4.27 ± 0.76 millimeters per minute (mm/min) on 20 sides of 10 healthy controls, 4.11 ± 2.91 mm/min on the affected sides of the patients with Bell's palsy, and 6.03 ± 3.13 mm/min on the nonparalyzed sides of the patients. MCT rate was statistically significantly faster in the nonparalyzed side when compared to the paralyzed side in Bell's palsy patients (P = 0.001). MCT rates were not significantly different in the control group and paralyzed sides of the Bell's palsy patients (P = 0.810). The MCT rate was statistically significantly faster in the nonparalyzed sides of Bell's palsy patients when compared to the controls (P = 0.017). This study showed a faster MCT rate on the nonparalyzed side in Bell's palsy patients when compared to the paralyzed side and the control subjects. A compensatory mechanism could be the underlying reason for faster MCT on the nonparalyzed side. Further studies on larger patient groups are needed to investigate the effect of facial paralysis on the MCT and changes of facial nerve function on the opposite, nonparalyzed side of the face.
Debunking the viper's strike: harmless snakes kill a common assumption.
Penning, David A; Sawvel, Baxter; Moon, Brad R
2016-03-01
To survive, organisms must avoid predation and acquire nutrients and energy. Sensory systems must correctly differentiate between potential predators and prey, and elicit behaviours that adjust distances accordingly. For snakes, strikes can serve both purposes. Vipers are thought to have the fastest strikes among snakes. However, strike performance has been measured in very few species, especially non-vipers. We measured defensive strike performance in harmless Texas ratsnakes and two species of vipers, western cottonmouths and western diamond-backed rattlesnakes, using high-speed video recordings. We show that ratsnake strike performance matches or exceeds that of vipers. In contrast with the literature over the past century, vipers do not represent the pinnacle of strike performance in snakes. Both harmless and venomous snakes can strike with very high accelerations that have two key consequences: the accelerations exceed values that can cause loss of consciousness in other animals, such as the accelerations experienced by jet pilots during extreme manoeuvres, and they make the strikes faster than the sensory and motor responses of mammalian prey and predators. Both harmless and venomous snakes can strike faster than the blink of an eye and often reach a target before it can move. © 2016 The Author(s).
Enabling Near Real-Time Remote Search for Fast Transient Events with Lossy Data Compression
NASA Astrophysics Data System (ADS)
Vohl, Dany; Pritchard, Tyler; Andreoni, Igor; Cooke, Jeffrey; Meade, Bernard
2017-09-01
We present a systematic evaluation of JPEG2000 (ISO/IEC 15444) as a transport data format to enable rapid remote searches for fast transient events as part of the Deeper Wider Faster programme. Deeper Wider Faster programme uses 20 telescopes from radio to gamma rays to perform simultaneous and rapid-response follow-up searches for fast transient events on millisecond-to-hours timescales. Deeper Wider Faster programme search demands have a set of constraints that is becoming common amongst large collaborations. Here, we focus on the rapid optical data component of Deeper Wider Faster programme led by the Dark Energy Camera at Cerro Tololo Inter-American Observatory. Each Dark Energy Camera image has 70 total coupled-charged devices saved as a 1.2 gigabyte FITS file. Near real-time data processing and fast transient candidate identifications-in minutes for rapid follow-up triggers on other telescopes-requires computational power exceeding what is currently available on-site at Cerro Tololo Inter-American Observatory. In this context, data files need to be transmitted rapidly to a foreign location for supercomputing post-processing, source finding, visualisation and analysis. This step in the search process poses a major bottleneck, and reducing the data size helps accommodate faster data transmission. To maximise our gain in transfer time and still achieve our science goals, we opt for lossy data compression-keeping in mind that raw data is archived and can be evaluated at a later time. We evaluate how lossy JPEG2000 compression affects the process of finding transients, and find only a negligible effect for compression ratios up to 25:1. We also find a linear relation between compression ratio and the mean estimated data transmission speed-up factor. Adding highly customised compression and decompression steps to the science pipeline considerably reduces the transmission time-validating its introduction to the Deeper Wider Faster programme science pipeline and enabling science that was otherwise too difficult with current technology.
Vector computer memory bank contention
NASA Technical Reports Server (NTRS)
Bailey, D. H.
1985-01-01
A number of vector supercomputers feature very large memories. Unfortunately the large capacity memory chips that are used in these computers are much slower than the fast central processing unit (CPU) circuitry. As a result, memory bank reservation times (in CPU ticks) are much longer than on previous generations of computers. A consequence of these long reservation times is that memory bank contention is sharply increased, resulting in significantly lowered performance rates. The phenomenon of memory bank contention in vector computers is analyzed using both a Markov chain model and a Monte Carlo simulation program. The results of this analysis indicate that future generations of supercomputers must either employ much faster memory chips or else feature very large numbers of independent memory banks.
NASA Technical Reports Server (NTRS)
Rarig, P. L.
1980-01-01
A program to calculate upwelling infrared radiation was modified to operate efficiently on the STAR-100. The modified software processes specific test cases significantly faster than the initial STAR-100 code. For example, a midlatitude summer atmospheric model is executed in less than 2% of the time originally required on the STAR-100. Furthermore, the optimized program performs extra operations to save the calculated absorption coefficients. Some of the advantages and pitfalls of virtual memory and vector processing are discussed along with strategies used to avoid loss of accuracy and computing power. Results from the vectorized code, in terms of speed, cost, and relative error with respect to serial code solutions are encouraging.
Consolidation of lunar regolith: Microwave versus direct solar heating
NASA Technical Reports Server (NTRS)
Kunitzer, J.; Strenski, D. G.; Yankee, S. J.; Pletka, B. J.
1991-01-01
The production of construction materials on the lunar surface will require an appropriate fabrication technique. Two processing methods considered as being suitable for producing dense, consolidated products such as bricks are direct solar heating and microwave heating. An analysis was performed to compare the two processes in terms of the amount of power and time required to fabricate bricks of various size. The regolith was considered to be a mare basalt with an overall density of 60 pct. of theoretical. Densification was assumed to take place by vitrification since this process requires moderate amounts of energy and time while still producing dense products. Microwave heating was shown to be significantly faster compared to solar furnace heating for rapid production of realistic-size bricks.
NASA Astrophysics Data System (ADS)
Attia, Khalid A. M.; Nassar, Mohammed W. I.; El-Zeiny, Mohamed B.; Serag, Ahmed
2017-01-01
For the first time, a new variable selection method based on swarm intelligence namely firefly algorithm is coupled with three different multivariate calibration models namely, concentration residual augmented classical least squares, artificial neural network and support vector regression in UV spectral data. A comparative study between the firefly algorithm and the well-known genetic algorithm was developed. The discussion revealed the superiority of using this new powerful algorithm over the well-known genetic algorithm. Moreover, different statistical tests were performed and no significant differences were found between all the models regarding their predictabilities. This ensures that simpler and faster models were obtained without any deterioration of the quality of the calibration.
Enantioselective behaviour of tetraconazole during strawberry wine-making process.
Liu, Na; Pan, Xinglu; Zhang, Shuang; Ji, Mingshan; Zhang, Zhihong
2018-05-01
The fate of tetraconazole enantiomers in strawberries during wine-making process was studied. The residues were determined by ultra-performance convergence chromatography tandem triple quadrupole mass spectrometry after each process steps. Results indicated that there was significant enantioselective dissipation of tetraconazole enantiomers during the fermentation process. And (-)-tetraconazole degraded faster than (+)-tetraconazole. The half-lives of (-)-tetraconazole and (+)-tetraconazole were 3.12, 3.76 days with washing procedure and 3.18, 4.05 days without washing procedure. The processing factors of strawberry wine samples after each step were generally less than 1. In particular, the processing factors of the fermentation process were the lowest. The results could help facilitate more accurate risk assessments of tetraconazole during wine-making process. © 2018 Wiley Periodicals, Inc.
[Simultaneous bilateral cataract surgery--advantages and disadvantages].
Obuchowska, Iwona; Mariak, Zofia
2006-01-01
During the past decade, advances in techniques and technology led to major changes in cataract surgical practice patterns. In this progression towards ever faster eye rehabilitation after surgery, simultaneous bilateral cataract surgery (SBCS) may be the next and ultimate step. It is not routinely performed: however, there are certain situations in which SBCS might be beneficial to the patients. It has been considered a good option in patients who have significant cataract in both eyes and are not good candidates for having anesthesia and surgery twice. The question is, if the benefits by bilateral surgery justify the risk of simultaneous complications, in particular endophthalmitis. In this perspective we present the clinical, social and economic advantages and disadvantages of such surgical procedures.