Sample records for left turns

  1. Left-Turn Bays

    DOT National Transportation Integrated Search

    1996-05-01

    The topic of left-turn bays (left-turn lanes) involves the following three issues: 1.) Warrants; 2.) Bay Length and 3.) Design Details. This discussion paper deals with warrants and bay length -- including queue storage at signalized and unsignalized...

  2. Operational evaluation of right turns followed by U-turns as an alternative to direct left turns, Vol. 3

    DOT National Transportation Integrated Search

    2001-09-01

    This project evaluated the safety and operational impacts of two alternative left-turn treatments from driveways/side streets. The two treatments were: (1) Direct left turns (DLT) and, (2) Right turns followed by U-turns (RTUT). Ten sites were select...

  3. Safety evaluation of right turns followed by U-turns as an alternative to direct left turns : conflict analysis, Vol. 2

    DOT National Transportation Integrated Search

    2001-10-01

    This project evaluated the safety and operational impacts of two alternative left-turn treatments from driveways/side streets. The two treatments were (1) direct left turns and (2) right turns followed by U-turns. Safety analyses of the alternatives ...

  4. Safety evaluation of right turns followed by U-turns as an alternative to direct left turns : crash data analysis, Vol. 1

    DOT National Transportation Integrated Search

    2001-10-01

    This project evaluated the safety and operational impacts of two alternative left-turn treatments from driveway/side streets. The two treatments were: (1) direct left turns and, (2) right turns followed by U-turns. Safety analyses of the alternatives...

  5. Guidelines for the use of protected/permissive left-turn phasing

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

    Agent, K.R.

    1987-07-01

    Turning left across opposing traffic at a signalized intersection could result in a traffic accident, as well as create motorist delay. A solution to the left-turn problem may be the addition of a left-turn phase when certain guidelines are met. After a decision has been made to add a left-turn phase, one of two basic alternative phasing methods is . In a previous research study, the results of replacing protected-only (exclusive) with protected/permissive (permissive) phasing at four trial intersections were studied. The permissive phasing provided a substantial reduction in delay and was popular with local drivers. However, several left-turn relatedmore » accidents occurred at those locations. Since those initial trial installations, permissive phasing has been used at several intersections across the state. This created a larger data base that could be used to determine when permissive phasing could be used without causing an accident problem. The objective of this study was to develop guidelines to aid traffic engineers in deciding whether permissive left-turn phasing is appropriate for use at a given location.« less

  6. Modeling left-turn crash occurrence at signalized intersections by conflicting patterns.

    PubMed

    Wang, Xuesong; Abdel-Aty, Mohamed

    2008-01-01

    In order to better understand the underlying crash mechanisms, left-turn crashes occurring at 197 four-legged signalized intersections over 6 years were classified into nine patterns based on vehicle maneuvers and then were assigned to intersection approaches. Crash frequency of each pattern was modeled at the approach level by mainly using Generalized Estimating Equations (GEE) with the Negative Binomial as the link function to account for the correlation among the crash data. GEE with a binomial logit link function was also applied for patterns with fewer crashes. The Cumulative Residuals test shows that, for correlated left-turn crashes, GEE models usually outperformed basic Negative Binomial models. The estimation results show that there are obvious differences in the factors that cause the occurrence of different left-turn collision patterns. For example, for each pattern, the traffic flows to which the colliding vehicles belong are identified to be significant. The width of the crossing distance (represented by the number of through lanes on the opposing approach of the left-turning traffic) is associated with more left-turn traffic colliding with opposing through traffic (Pattern 5), but with less left-turning traffic colliding with near-side crossing through traffic (Pattern 8). The safety effectiveness of the left-turning signal is not consistent for different crash patterns; "protected" phasing is correlated with fewer Pattern 5 crashes, but with more Pattern 8 crashes. The study indicates that in order to develop efficient countermeasures for left-turn crashes and improve safety at signalized intersections, left-turn crashes should be considered in different patterns.

  7. Guidelines for the use of no U-turn and no left-turn signs.

    DOT National Transportation Integrated Search

    1994-01-01

    The objective of this study was to establish a set of written guidelines identifying traffic and road conditions where No U-Turn and No Left Turn signs should be installed. The effect of these signs on traffic safety was also investigated. A question...

  8. Displaced left turn intersection : informational guide.

    DOT National Transportation Integrated Search

    2014-08-01

    This document provides information and guidance on the Displaced Left Turn (DLT) intersection. To the extent possible, the : guide addresses a variety of conditions found in the United States, to achieve designs suitable for a wide array of potential...

  9. Development of guidelines for triple left and dual right-turn lanes : technical report.

    DOT National Transportation Integrated Search

    2011-07-01

    Left- or right-turn lanes at intersections improve safety and operations by separating turning and through vehicles. At intersections : with heavy turning demand, it may be necessary to provide multiple turn lanes. Triple left-turn (TLT) and dual rig...

  10. Development of pedestrian safety based warrants for permissive left-turn control

    DOT National Transportation Integrated Search

    2010-12-01

    At the intersections with permissive only signal control, pedestrians will move at the permissive phase with the parallel through vehicular movement and left-turn vehicles, the left-turn vehicles have to yield to both opposing through vehicles and pe...

  11. Childrens' left-turning preference is not modulated by magical ideation.

    PubMed

    Streuli, Jürg C; Obrist, Gina; Brugger, Peter

    2017-01-01

    The literature on human turning preferences is inconsistent. While the few studies with children below 14 years of age uniformly describe an overall left-turning (counterclockwise) tendency, a recent Internet study with more than 1500 adults found a right-sided (clockwise) bias. We set out to investigate spontaneous turning behaviour in children age 5-3 years and, based on neuropsychiatric work in adults, also explored a potential association with magical thinking. Findings indicated a clear left-turning preference, independent of a participant's sex and handedness. Whether a child responded a question about the existence of extrasensory communication in the affirmative or not was unrelated to direction and size of turning bias and lateral preference. Our results are consistent with a left-sided turning preference reported for children, but in opposition to the clockwise bias recently described in a large-scale study with adults. Whether they point to a maturational gradient in the preferred direction of spontaneous whole-body rotation or rather to a lack of comparability between measures used in observational versus Internet-based studies remains to be further investigated. Regarding a purported association between body turns and magical thinking, our study is preliminary, as only one single question was used to probe the latter.

  12. Thunderstorm-scale variations of echoes associated with left-turn tornado families

    NASA Technical Reports Server (NTRS)

    Forbes, G. S.

    1977-01-01

    The origin of tornadoes is studied on the basis of changing radar echo shapes and tornado location relative to the echoes. Three types of tornadoes appear to be associated with different hook echo configurations. No-turn or right-turn tornadoes are linked to a steady hook which does not change shape or orientation. Left-turn tornado families are generated in cases where the hook is unsteady and changes orientation at each successive tornado birth. Finally, left-turn tornado families may also be formed when the hook undergoes no orientation change and the tornadoes move along the rear of the hook. The correlation between a thunderstorm-scale cycle and periodic tornado production is also discussed.

  13. Evaluation of Revised Left Turn Signalization : Final Report

    DOT National Transportation Integrated Search

    1997-11-01

    Modified left turn signals had shown cost savings over the old style of traffic signals in initial installation and maintenance. This evaluation was conducted to determine whether those savings would be justified by no increase in the accident rates ...

  14. Left-turn phase: permissive, protected, or both? A quasi-experimental design in New York City.

    PubMed

    Chen, Li; Chen, Cynthia; Ewing, Reid

    2015-03-01

    The practice of left-turn phasing selection (permissive, protected-only, or both) varies from one locality to another. The literature evidence on this issue is equally mixed and insufficient. In this study, we evaluate the safety impacts of changing left-turn signal phasing from permissive to protected/permissive or protected-only at 68 intersections in New York City using a rigorous quasi-experimental design accompanied with regression modeling. Changes in police reported crashes including total crashes, multiple-vehicle crashes, left-turn crashes, pedestrian crashes and bicyclist crashes were compared between before period and after period for the treatment group and comparison group by means of negative binomial regression using a Generalized Estimating Equations (GEE) technique. Confounding factors such as the built environment characteristics that were not controlled in comparison group selection are accounted for by this approach. The results show that the change of permissive left-turn signal phasing to protected/permissive or protected-only signal phasing does not result in a significant reduction in intersection crashes. Though the protected-only signal phasing does reduce the left-turn crashes and pedestrian crashes, this reduction was offset by a possible increase in over-taking crashes. These results suggest that left-turn phasing should not be treated as a universal solution that is always better than the permissive control for left-turn vehicles. The selection and implementation of left-turn signal phasing needs to be done carefully, considering potential trade-offs between safety and delay, and many other factors such as geometry, traffic flows and operations. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Influence of bus stop with left-turn lines between two adjacent signalized intersections

    NASA Astrophysics Data System (ADS)

    Pang, Ming-Bao; Ye, Lan-Hang; Pei, Ya-Nan

    2016-08-01

    Based on the symmetric two-lane Nagel-Schreckenberg (STNS) model, a three-lane cellular automaton model between two intersections containing a bus stop with left-turning buses is established in which model the occurrences of vehicle accidents are taken into account. The characteristics of traffic flows with different ratios of left-turn lines are discussed via the simulation experiments. The results indicate that the left-turn lines have more negative effects on capacity, accident rate as well as delay if the stop is located close to the intersections, where the negative effect in a near-side stop is more severe than that in a far-side one. The range of appropriate position for a bus stop without the bottleneck effect becomes more and more narrow with the increase of the ratio of left-turn bus lines. When the inflow is small, a short signal cycle and a reasonable offset are beneficial. When the inflow reaches or exceeds the capacity, a longer signal cycle is helpful. But if the stop position is inappropriate, the increase of cycle fails in reducing the negative effect of left-turning buses and the effectiveness of offset is weakened. Project supported by the National Natural Science Foundation of China (Grant No. 50478088) and the Natural Science Foundation of Hebei Province, China (Grant No. E2015202266).

  16. Dynamic flashing yellow arrow (FYA) : a study on variable left turn model operational and safety impacts, [technical summary].

    DOT National Transportation Integrated Search

    2013-12-01

    Traffic engineers use various left-turn signalization : methods to find an optimal balance of safety and : efficiency. While protected/permitted left-turn : configurations allow most left-turning traffic to : turn during the protected phase, the perm...

  17. Development of guidelines for permitted left-turn phasing using flashing yellow arrows : final report.

    DOT National Transportation Integrated Search

    2015-06-01

    The objective of this project was to develop guidelines for time-of-day use of permitted left-turn phasing, : which can then be implemented using flashing yellow arrows (FYA). This required determining how the risk : for left-turn crashes varied as t...

  18. Safety effects of traffic signing for left turn flashing yellow arrow signals.

    PubMed

    Schattler, Kerrie L; Gulla, Cody J; Wallenfang, Travis J; Burdett, Beau A; Lund, Jessica A

    2015-02-01

    In 2010, the left turn flashing yellow arrow (FYA) signal displays were installed at signalized intersections on state routes in the Peoria, Illinois, area. Supplemental traffic signs with text "Left Turn Yield on Flashing Yellow Arrow" were mounted on the mast arm adjacent to the left turn signal at over half of the FYA installations. The purpose of this paper is to present the results of the effectiveness evaluation of the FYA supplemental sign on safety. Analyses are presented on the effects of the FYA supplemental sign for all drivers and a subset of drivers age 65 and older. A crash-based comparison of 164 FYA approaches including 90 approaches with the sign and 74 approaches without the sign showed greater crash reductions when the supplemental FYA sign was present. The results also showed that crashes involving drivers age 65 and older did not experience the same magnitudes of crash reductions as compared to all drivers. The findings of this research indicate that supplemental FYA signs may help in improving safety for left-turning vehicles during the permissive interval. Thus, it is recommended that supplemental signs be used when initially implementing the FYA, and that effort to educate the driving public on new traffic control be made to further improve safety at signalized intersections. Copyright © 2014. Published by Elsevier Ltd.

  19. Bicyclists' inclination and ability to search behind before turning left

    DOT National Transportation Integrated Search

    1980-02-01

    Author's abstract: Research (Cross and Fisher, 1977) has identified a relatively high incidence (8.4%) bicycle/motor-vehicle accident type in which a bicyclist initiates a left-hand turn without searching to the rear or signaling and is struck by an ...

  20. Dynamic flashing yellow arrow (FYA) : a study on variable left turn mode operational and safety impacts.

    DOT National Transportation Integrated Search

    2013-12-01

    Accommodating left turns at signalized intersections has been a challenge for traffic engineers as they : seek balance between two conflicting goals; capacity and safety. The use of a four-section head for the left-turn : lane only with a flashing ye...

  1. Development of left-turn lane guidelines for signalized and unsignalized intersections.

    DOT National Transportation Integrated Search

    2004-01-01

    It is generally accepted that the level of service (LOS) at intersections significantly affects the overall LOS of the road system. It is also known that the LOS at an intersection can be adversely affected by frequently allowing left-turning vehicle...

  2. Safety evaluation of intersections with dynamic use of exit-lanes for left-turn using field data.

    PubMed

    Zhao, Jing; Liu, Yue

    2017-05-01

    As a newly proposed unconventional intersection design, the exit-lanes for left-turn (EFL) intersection is found to be effective in increasing the intersection capacity with high level of application flexibility, especially under heavy left-turn traffic conditions. However, the operational safety of EFL is of most concern to the authority prior to its implementation. This paper evaluates the safety of the EFL intersections by studying the behavior of left-turn maneuvers using field data collected at 7 locations in China. A total of 22830 left-turn vehicles were captured, in which 9793 vehicles turned left using the mixed-usage area. Four potential safety problems, including the red-light violations, head-on collision risks, trapped vehicles, and rear-end crash risks, were discussed. Statistical analyses were carried out to compare the safety risk between the EFL intersection and the conventional one. Results indicate that the safety problems of EFL intersections mainly lie in higher percentages in red-light violations at the pre-signal (1.83% higher), wrong-way violation problems during the peak hours (the violation rate reaches up to 11.07%), and the lower travel speeds in the mixed-usage area (18.75% lower). Such risks can be counteracted, however, by providing more guiding information, installing cameras to investigate and punish violation maneuvers, and adjusting design parameter values for layout design and signal timing, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. State-of-the-art literature review on permissive/protected left-turn control.

    DOT National Transportation Integrated Search

    2013-06-01

    In spring 2010, the Illinois Department of Transportation initiated an areawide implementation to integrate the : flashing yellow arrow as the display for the left-turn permissive interval at more than 100 intersections operating : with protected/per...

  4. No turning, a mouse mutation causing left-right and axial patterning defects.

    PubMed

    Melloy, P G; Ewart, J L; Cohen, M F; Desmond, M E; Kuehn, M R; Lo, C W

    1998-01-01

    Patterning along the left/right axes helps establish the orientation of visceral organ asymmetries, a process which is of fundamental importance to the viability of an organism. A linkage between left/right and axial patterning is indicated by the finding that a number of genes involved in left/right patterning also play a role in anteroposterior and dorsoventral patterning. We have recovered a spontaneous mouse mutation causing left/right patterning defects together with defects in anteroposterior and dorsoventral patterning. This mutation is recessive lethal and was named no turning (nt) because the mutant embryos fail to undergo embryonic turning. nt embryos exhibit cranial neural tube closure defects and malformed somites and are caudally truncated. Development of the heart arrests at the looped heart tube stage, with cardiovascular defects indicated by ballooning of the pericardial sac and the pooling of blood in various regions of the embryo. Interestingly, in nt embryos, the direction of heart looping was randomized. Nodal and lefty, two genes that are normally expressed only in the left lateral plate mesoderm, show expression in the right and left lateral plate mesoderm. Lefty, which is normally also expressed in the floorplate, is not found in the prospective floor plate of nt embryos. This suggests the possibility of notochordal defects. This was confirmed by histological analysis and the examination of sonic hedgehog, Brachyury, and HNF-3 beta gene expression. These studies showed that the notochord is present in the early nt embryo, but degenerates as development progresses. Overall, these findings support the hypothesis that the notochord plays an active role in left/right patterning. Our results suggest that nt may participate in this process by modulating the notochordal expression of HNF-3 beta.

  5. Mirrors in the PDB: left-handed alpha-turns guide design with D-amino acids.

    PubMed

    Annavarapu, Srinivas; Nanda, Vikas

    2009-09-22

    Incorporating variable amino acid stereochemistry in molecular design has the potential to improve existing protein stability and create new topologies inaccessible to homochiral molecules. The Protein Data Bank has been a reliable, rich source of information on molecular interactions and their role in protein stability and structure. D-amino acids rarely occur naturally, making it difficult to infer general rules for how they would be tolerated in proteins through an analysis of existing protein structures. However, protein elements containing short left-handed turns and helices turn out to contain useful information. Molecular mechanisms used in proteins to stabilize left-handed elements by L-amino acids are structurally enantiomeric to potential synthetic strategies for stabilizing right-handed elements with D-amino acids. Propensities for amino acids to occur in contiguous alpha(L) helices correlate with published thermodynamic scales for incorporation of D-amino acids into alpha(R) helices. Two backbone rules for terminating a left-handed helix are found: an alpha(R) conformation is disfavored at the amino terminus, and a beta(R) conformation is disfavored at the carboxy terminus. Helix capping sidechain-backbone interactions are found which are unique to alpha(L) helices including an elevated propensity for L-Asn, and L-Thr at the amino terminus and L-Gln, L-Thr and L-Ser at the carboxy terminus. By examining left-handed alpha-turns containing L-amino acids, new interaction motifs for incorporating D-amino acids into right-handed alpha-helices are identified. These will provide a basis for de novo design of novel heterochiral protein folds.

  6. Mirrors in the PDB: left-handed α-turns guide design with D-amino acids

    PubMed Central

    Annavarapu, Srinivas; Nanda, Vikas

    2009-01-01

    Background Incorporating variable amino acid stereochemistry in molecular design has the potential to improve existing protein stability and create new topologies inaccessible to homochiral molecules. The Protein Data Bank has been a reliable, rich source of information on molecular interactions and their role in protein stability and structure. D-amino acids rarely occur naturally, making it difficult to infer general rules for how they would be tolerated in proteins through an analysis of existing protein structures. However, protein elements containing short left-handed turns and helices turn out to contain useful information. Molecular mechanisms used in proteins to stabilize left-handed elements by L-amino acids are structurally enantiomeric to potential synthetic strategies for stabilizing right-handed elements with D-amino acids. Results Propensities for amino acids to occur in contiguous αL helices correlate with published thermodynamic scales for incorporation of D-amino acids into αR helices. Two backbone rules for terminating a left-handed helix are found: an αR conformation is disfavored at the amino terminus, and a βR conformation is disfavored at the carboxy terminus. Helix capping sidechain-backbone interactions are found which are unique to αL helices including an elevated propensity for L-Asn, and L-Thr at the amino terminus and L-Gln, L-Thr and L-Ser at the carboxy terminus. Conclusion By examining left-handed α-turns containing L-amino acids, new interaction motifs for incorporating D-amino acids into right-handed α-helices are identified. These will provide a basis for de novo design of novel heterochiral protein folds. PMID:19772623

  7. Deciding alternative left turn signal phases using expert systems

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

    Chang, E.C.P.

    1988-01-01

    The Texas Transportation Institute (TTI) conducted a study to investigate the feasibility of applying artificial intelligence (AI) technology and expert systems (ES) design concepts to a traffic engineering problem. Prototype systems were developed to analyze user input, evaluate various reasoning, and suggest suitable left turn phase treatment. These systems were developed using AI programming tools on IBM PC/XT/AT-compatible microcomputers. Two slightly different systems were designed using AI languages; another was built with a knowledge engineering tool. These systems include the PD PROLOG and TURBO PROLOG AI programs, as well as the INSIGHT Production Rule Language.

  8. Driving simulator evaluation of drivers' response to intersections with dynamic use of exit-lanes for left-turn.

    PubMed

    Zhao, Jing; Yun, Meiping; Zhang, H Michael; Yang, Xiaoguang

    2015-08-01

    With the worsening of urban traffic congestion in large cities around the world, researchers have been looking for unconventional designs and/or controls to squeeze more capacity out of intersections, the most common bottlenecks of the road network. One of these innovative intersection designs, known as the exit-lanes for left-turn (EFL), opens up exit-lanes to be used by left-turn traffic with the help of an additional traffic light installed at the median opening (the pre-signal). This paper studies how drivers respond to EFL intersections with a series of driving simulator experiments. In our experiments, 64 drivers were recruited and divided into two groups. One group is trained to use the EFL while the other group is not. In addition, four scenarios were considered with different sign and marking designs and traffic conditions in the experiments. Results indicate that drivers show certain amount of confusion and hesitation when encountering an EFL intersection for the first time. They can be overcome, however, by increasing exposure through driver education or by cue provided from other vehicles. Moreover, drivers unfamiliar with EFL operation can make a left turn using the conventional left-turn lanes as usual. The EFL operation is not likely to pose any serious safety risk of the intersection in real life operations. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Evaluation of a Risk Awareness Perception Training Program on Novice Teen Driver Behavior at Left-Turn Intersections.

    PubMed

    McDonald, Catherine C; Kandadai, Venk; Loeb, Helen; Seacrist, Thomas; Lee, Yi-Ching; Bonfiglio, Dana; Fisher, Donald L; Winston, Flaura K

    Collisions at left turn intersections are among the most prevalent types of teen driver serious crashes, with inadequate surveillance as a key factor. Risk awareness perception training (RAPT) has shown effectiveness in improving hazard anticipation for latent hazards. The goal of this study was to determine if RAPT version 3 (RAPT-3) improved intersection turning behaviors among novice teen drivers when the hazards were not latent and frequent glancing to multiple locations at the intersection was needed. Teens aged 16-18 with ≤180 days of licensure were randomly assigned to: 1) an intervention group (n=18) that received RAPT-3 (Trained); or 2) a control group (n=19) that received no training (Untrained). Both groups completed RAPT-3 Baseline Assessment and the Trained group completed RAPT-3 Training and RAPT-3 Post Assessment. Training effects were evaluated on a driving simulator. Simulator ( gap selection errors and collisions ) and eye tracker ( traffic check errors) metrics from six left-turn stop sign controlled intersections in the Simulated Driving Assessment (SDA) were analyzed. The Trained group scored significantly higher in RAPT-3 Post Assessment than RAPT-3 Baseline Assessment (p< 0.0001). There were no significant differences in either traffic check and gap selection errors or collisions among Trained and Untrained teens in the SDA. Though Trained teens learned about hazard anticipation related to latent hazards, learning did not translate to performance differences in left-turn stop sign controlled intersections where the hazards were not latent. Our findings point to further research to better understand the challenges teens have with left turn intersections.

  10. Safety implications of the use of the flashing yellow arrow for permissive left turns.

    DOT National Transportation Integrated Search

    2011-01-01

    The use of the flashing yellow arrow (FYA) for permissive left turns is relatively new to California, with at least five : installations approved under a 2006 Federal Highway Administration (FHWA) Interim Approval memorandum. : Inclusion of formal gu...

  11. AUGMENTED REALITY CUES TO ASSIST OLDER DRIVERS WITH GAP ESTIMATION FOR LEFT-TURNS

    PubMed Central

    Rusch, Michelle L.; Schall, Mark C.; Lee, John D.; Dawson, Jeffrey D.; Rizzo, Matthew

    2014-01-01

    The objective of this study was to assess the effects of augmented reality (AR) cues designed to assist middle-aged and older drivers with a range of UFOV impairments, judging when to make left-turns across oncoming traffic. Previous studies have shown that AR cues can help middle-aged and older drivers respond to potential roadside hazards by increasing hazard detection without interfering with other driving tasks. Intersections pose a critical challenge for cognitively impaired drivers, prone to misjudge time-to-contact with oncoming traffic. We investigated whether AR cues improve or interfere with hazard perception in left-turns across oncoming traffic for drivers with age-related cognitive decline. Sixty-four middle-aged and older drivers with a range of UFOV impairment judged when it would be safe to turn left across oncoming traffic approaching the driver from the opposite direction in a rural stop-sign controlled intersection scenario implemented in a static base driving simulator. Outcome measures used to evaluate the effectiveness of AR cueing included: Time-to-Contact (TTC), Gap Time Variation (GTV), Response Rate, and Gap Response Variation (GRV). All drivers estimated TTCs were shorter in cued than in uncued conditions. In addition, drivers responded more often in cued conditions than in uncued conditions and GRV decreased for all drivers in scenarios that contained AR cues. For both TTC and response rate, drivers also appeared to adjust their behavior to be consistent with the cues, especially drivers with the poorest UFOV scores (matching their behavior to be close to middle-aged drivers). Driver ratings indicated that cueing was not considered to be distracting. Further, various conditions of reliability (e.g., 15% miss rate) did not appear to affect performance or driver ratings. PMID:24950128

  12. Augmented reality cues to assist older drivers with gap estimation for left-turns.

    PubMed

    Rusch, Michelle L; Schall, Mark C; Lee, John D; Dawson, Jeffrey D; Rizzo, Matthew

    2014-10-01

    The objective of this study was to assess the effects of augmented reality (AR) cues designed to assist middle-aged and older drivers with a range of UFOV impairments, judging when to make left-turns across oncoming traffic. Previous studies have shown that AR cues can help middle-aged and older drivers respond to potential roadside hazards by increasing hazard detection without interfering with other driving tasks. Intersections pose a critical challenge for cognitively impaired drivers, prone to misjudge time-to-contact with oncoming traffic. We investigated whether AR cues improve or interfere with hazard perception in left-turns across oncoming traffic for drivers with age-related cognitive decline. Sixty-four middle-aged and older drivers with a range of UFOV impairment judged when it would be safe to turn left across oncoming traffic approaching the driver from the opposite direction in a rural stop-sign controlled intersection scenario implemented in a static base driving simulator. Outcome measures used to evaluate the effectiveness of AR cueing included: Time-to-Contact (TTC), Gap Time Variation (GTV), Response Rate, and Gap Response Variation (GRV). All drivers estimated TTCs were shorter in cued than in uncued conditions. In addition, drivers responded more often in cued conditions than in uncued conditions and GRV decreased for all drivers in scenarios that contained AR cues. For both TTC and response rate, drivers also appeared to adjust their behavior to be consistent with the cues, especially drivers with the poorest UFOV scores (matching their behavior to be close to middle-aged drivers). Driver ratings indicated that cueing was not considered to be distracting. Further, various conditions of reliability (e.g., 15% miss rate) did not appear to affect performance or driver ratings. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Improved simulation of driver behavior : modeling protected and permitted left-turn operations at signalized intersections.

    DOT National Transportation Integrated Search

    2011-04-01

    "This report documents the findings from a research project that is focused on modeling protected and permitted left-turn operations at signalized intersection approaches. The projects primary objective is to document the microscopic characteristi...

  14. A Field and Simulator Evaluation of All-Red Clearance Intervals for Use in Left-Turn Applications

    DOT National Transportation Integrated Search

    2018-03-01

    As the implementation of the novel flashing yellow arrow (FYA) traffic control device advances throughout the country, agencies continually seek ways to improve intersection operations and safety, especially on left turns. For example, permissive lef...

  15. Effects of major-road vehicle speed and driver age and gender on left-turn gap acceptance.

    PubMed

    Yan, Xuedong; Radwan, Essam; Guo, Dahai

    2007-07-01

    Because the driver's gap-acceptance maneuver is a complex and risky driving behavior, it is a highly concerned topic for traffic safety and operation. Previous studies have mainly focused on the driver's gap acceptance decision itself but did not pay attention to the maneuver process and driving behaviors. Using a driving simulator experiment for left-turn gap acceptance at a stop-controlled intersection, this study evaluated the effects of major traffic speed and driver age and gender on gap acceptance behaviors. The experiment results illustrate relationships among drivers' left-turn gap decision, driver's acceleration rate, steering action, and the influence of the gap-acceptance maneuver on the vehicles in the major traffic stream. The experiment results identified an association between high crash risk and high traffic speed at stop-controlled intersections. The older drivers, especially older female drivers, displayed a conservative driving attitude as a compensation for reduced driving ability, but also showed to be the most vulnerable group for the relatively complex driving maneuvers.

  16. Use of Flashing Yellow Operations to Improve Safety at Signals with Protected-Permissive Left Turn (PPLT) Operations

    DOT National Transportation Integrated Search

    2012-10-01

    MUTCD 2009 Edition suggests the use of Flashing Yellow Arrow (FYA) indication in replacement of green ball indication for permissive left-turn signal in presence of separate signal heads. Currently, there is no clear guidance on how to implement flas...

  17. Use of flashing yellow operations to improve safety at signals with protected-permissive left turn (PPLT) operations

    DOT National Transportation Integrated Search

    2012-10-01

    MUTCD 2009 Edition suggests the use of Flashing Yellow Arrow (FYA) indication in replacement of green ball indication for permissive left-turn signal in presence of separate signal heads. Currently, there is no clear guidance on how to implement flas...

  18. Left-handed helical preference in an achiral peptide chain is induced by an L-amino acid in an N-terminal type II β-turn.

    PubMed

    De Poli, Matteo; De Zotti, Marta; Raftery, James; Aguilar, Juan A; Morris, Gareth A; Clayden, Jonathan

    2013-03-15

    Oligomers of the achiral amino acid Aib adopt helical conformations in which the screw-sense may be controlled by a single N-terminal residue. Using crystallographic and NMR techniques, we show that the left- or right-handed sense of helical induction arises from the nature of the β-turn at the N terminus: the tertiary amino acid L-Val induces a left-handed type II β-turn in both the solid state and in solution, while the corresponding quaternary amino acid L-α-methylvaline induces a right-handed type III β-turn.

  19. Modeling the frequency of opposing left-turn conflicts at signalized intersections using generalized linear regression models.

    PubMed

    Zhang, Xin; Liu, Pan; Chen, Yuguang; Bai, Lu; Wang, Wei

    2014-01-01

    The primary objective of this study was to identify whether the frequency of traffic conflicts at signalized intersections can be modeled. The opposing left-turn conflicts were selected for the development of conflict predictive models. Using data collected at 30 approaches at 20 signalized intersections, the underlying distributions of the conflicts under different traffic conditions were examined. Different conflict-predictive models were developed to relate the frequency of opposing left-turn conflicts to various explanatory variables. The models considered include a linear regression model, a negative binomial model, and separate models developed for four traffic scenarios. The prediction performance of different models was compared. The frequency of traffic conflicts follows a negative binominal distribution. The linear regression model is not appropriate for the conflict frequency data. In addition, drivers behaved differently under different traffic conditions. Accordingly, the effects of conflicting traffic volumes on conflict frequency vary across different traffic conditions. The occurrences of traffic conflicts at signalized intersections can be modeled using generalized linear regression models. The use of conflict predictive models has potential to expand the uses of surrogate safety measures in safety estimation and evaluation.

  20. Bolivia’s Left Turn Toward Rentier Plurinationalism And Its Effects On Ethnic Tensions And Solidarity

    DTIC Science & Technology

    2016-06-01

    utilities and gas pipelines sparked a broad societal solidarity movement against transnational corporate control of water and gas . The 2000 Water Wars...Constitution referendum, funds for social programs were to be allocated exclusively from hydrocarbon and natural gas rents. A. BOLIVIA’S LEFT TURN...Cartographies,” 991–992. 4 sector toward nationalization. The Bolivian energy sector, “natural gas , in particular” has “become the backbone of the

  1. Use of Flashing Yellow Operations to Improve Safety at Signals with Protected-Permissive Left Turn (PPLT)Operations : Project Summary

    DOT National Transportation Integrated Search

    2011-08-31

    The 2009 edition of the federal MUTCD suggests the use of the flashing yellow arrow (FYA) indication in lieu : of the green ball indication for permissive left-turn signals in the presence of separate signal heads. Currently, : there are no clear gui...

  2. 32 CFR 636.23 - Turning movements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... from a position as close to the right edge or right curb of the roadway as possible. (c) Left-turns will be made from a position as close to the center line as possible or from a left turn lane, if...

  3. 32 CFR 636.23 - Turning movements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... from a position as close to the right edge or right curb of the roadway as possible. (c) Left-turns will be made from a position as close to the center line as possible or from a left turn lane, if...

  4. Safety evaluation of signal installation with and without left turn lanes on two lane roads in rural and suburban areas.

    DOT National Transportation Integrated Search

    2014-10-01

    Data from 117 intersections on two lane roads in rural and suburban areas in North Carolina were used to determine the safety : effect of signalization with and without left turn lanes. This was a before-after study that was conducted using the empir...

  5. Training Strategies and Materials : Use of Flashing Yellow Operations to Improve Safety at Signals with Protected-Permissive Left Turn (PPLT) Operations

    DOT National Transportation Integrated Search

    2012-08-01

    TxDOT project 0-6568 Use of Flashing Yellow Operations to Improve Safety at Signals with : Protected-Permissive Left Turn (PPLT) Operations has developed guidelines for : implementation of FYA PPLT displays including general guidelines on the F...

  6. Left-turn lanes at unsignalized median openings.

    DOT National Transportation Integrated Search

    2014-03-01

    Due to the frequent presence of median openings in urban arterial settings, the requirements for the deceleration and : storage of turning vehicles (e.g. AASHTO Green Book) often exceed the available length between two adjacent : openings which leave...

  7. Dynamic flashing yellow arrow (FYA): a study on variable left-turn mode operational and safety impacts phase II - model expansion and testing.

    DOT National Transportation Integrated Search

    2016-06-01

    The flashing yellow arrow (FYA) signal display creates an opportunity to enhance the left-turn phase with a : variable mode that can be changed on demand. The previously developed decision support system (DSS) in : phase I facilitated the selection o...

  8. Dynamic flashing yellow arrow (FYA): a study on variable left-turn mode operational and safety impacts phase II - model expansion and testing : [summary].

    DOT National Transportation Integrated Search

    2016-05-01

    In phase two of this project, the UCF team further developed the DSS to automate selection of FYA left-turn modes based on traffic volumes at intersections acquired in real time from existing sensors.

  9. Asymmetry of flight and escape turning responses in horses.

    PubMed

    Austin, N P; Rogers, L J

    2007-09-01

    We investigated whether horses display greater reactivity to a novel stimulus presented in the left compared to the right monocular visual field, and whether a population bias exists for escape turning when the same stimulus was presented binocularly. Domestic horses (N=30) were tested on three occasions by a person opening an umbrella five metres away and then approaching. The distance each horse moved away before stopping was measured. Distance was greatest for approach on the left side, indicating right hemisphere control of flight behaviour, and thus followed the same pattern found previously in other species. When order of monocular presentation was considered, an asymmetry was detected. Horses tested initially on the left side exhibited greater reactivity for left approach, whereas horses tested on the right side first displayed no side difference in reactivity. Perhaps left hemisphere inhibition of flight response allowed horses to learn that the stimulus posed no threat and this information was transferred to the right hemisphere. No population bias existed for the direction of escape turning, but horses that turned to the right when approached from the front were found to exhibit longer flight distances than those that turned to the left.

  10. Revised Planning Methodology For Signalized Intersections And Operational Analysis Of Exclusive Left-Turn Lanes, A Simulation-Based Method, Part - I: Literature Review (Final Report)

    DOT National Transportation Integrated Search

    1996-04-01

    THE STUDY INVESTIGATES THE APPLICATION OF SIMULATION ALONG WITH FIELD OBSERVATIONS FOR ESTIMATION OF EXCLUSIVE LEFT-TURN SATURATION FLOW RATE AND CAPACITY. THE ENTIRE RESEARCH HAS COVERED THE FOLLOWING PRINCIPAL SUBJECTS: (1) A SATURATION FLOW MODEL ...

  11. Design criteria for median turn lanes.

    DOT National Transportation Integrated Search

    1978-03-01

    This study was initiated with an extensive literature review and survey of : left-turn median lane practices in Texas cities. The initial phase identified : characteristics of urban arterial accidents, basic design elements, current use of : left-tur...

  12. Family matters: Directionality of turning bias while kissing is modulated by context.

    PubMed

    Sedgewick, Jennifer R; Elias, Lorin J

    2016-01-28

    When leaning forward to kiss to a romantic partner, individuals tend to direct their kiss to the right more often than the left. Studies have consistently demonstrated this kissing asymmetry, although other factors known to influence lateral biases, such as sex or situational context, had yet to be explored. The primary purpose of our study was to investigate if turning direction was consistent between a romantic (parent-parent) and parental (parent-child) kissing context, and secondly, to examine if sex differences influenced turning bias between parent-child kissing partners. An archival analysis coded the direction of turning bias for 161 images of romantic kissing (mothers kissing fathers) and 529 images of parental kissing (mothers or fathers kissing sons or daughters). The results indicated that the direction of turning bias differed between kissing contexts. As expected, a right-turn bias was observed for romantic kissing; however, a left-turn bias was exhibited for parental kissing. There was no significant difference of turning bias between any parent-child kissing partners. Interpretations for the left-turn bias discuss parental kissing as a learned lateral behaviour.

  13. Effects of turning and through lane sharing on traffic performance at intersections

    NASA Astrophysics Data System (ADS)

    Li, Xiang; Sun, Jian-Qiao

    2016-02-01

    Turning vehicles strongly influence traffic flows at intersections. Effective regulation of turning vehicles is important to achieve better traffic performance. This paper studies the impact of lane sharing and turning signals on traffic performance at intersections by using cellular automata. Both right-turn and left-turn lane sharing are studied. Interactions between vehicles and pedestrians are considered. The transportation efficiency, road safety and energy economy are the traffic performance metrics. Extensive simulations are carried out to study the traffic performance indices. It is observed that shared turning lanes and permissive left-turn signal improve the transportation efficiency and reduce the fuel consumption in most cases, but the safety is usually sacrificed. It is not always beneficial for the through vehicles when they are allowed to be in the turning lanes.

  14. Head-turning asymmetries during kissing and their association with lateral preference.

    PubMed

    Ocklenburg, Sebastian; Güntürkün, Onur

    2009-01-01

    A head-turning bias to the right side is one of the earliest functional asymmetries in human development and is already present during the final weeks of gestation. To test whether head-turning preference is related to other lateral preferences in adults, kissing behaviour of participants towards a symmetrical doll was observed to assess their spontaneous head-turning preference. Additionally, participants' individual handedness, footedness, and eye preference were determined using questionnaires. A significant difference in handedness and footedness, but not eye preference, was found between left- and right-kissers, with right-kissers showing a stronger right-sided bias than left-kissers. These results support the assumption that the head-turning bias in humans may be able to induce or enhance other asymmetries of perception and action.

  15. Turning off artistic ability: the influence of left DBS in art production.

    PubMed

    Drago, V; Foster, P S; Okun, M S; Cosentino, F I I; Conigliaro, R; Haq, I; Sudhyadhom, A; Skidmore, F M; Heilman, K M

    2009-06-15

    The influence of Parkinson's disease (PD) as well as deep brain stimulation (DBS) on visual-artistic production of people who have been artists is unclear. We systematically assessed the artistic-creative productions of a patient with PD who was referred to us for management of a left subthalamic region (STN) DBS. The patient was an artist before her disease started, permitting us to analyze changes in her artistic-creative production over the course of the illness and during her treatment with DBS. We collected her paintings from four time periods: Time 1 (Early Pre-Presymptomatic), Time 2 (Later Presymptomatic), Time 3 (Symptomatic), and Time 4 (DBS Symptomatic). A total of 59 paintings were submitted to a panel of judges, who rated the paintings on 6 different artistic qualities including: aesthetics, closure, evocative impact, novelty, representation, technique. Aesthetics and evocative impact significantly declined from Time 2 to Time 4. Representation and technique indicated a curvilinear relationship, with initial improvement from Time 1 to Time 2 followed by a decline from Time 2 to Time 4. These results suggest that left STN/SNR-DBS impacted artistic performances in our patient. The reason for these alterations is not known, but it might be that alterations of left hemisphere functions induce a hemispheric bias reducing the influence the right hemisphere which is important for artistic creativity. The left hemisphere itself plays a critical role in artistic creativity and DBS might have altered left hemisphere functions or altered the mesolimbic system which might have also influenced creativity. Future studies will be required to learn how PD and DBS influence creativity.

  16. Effective measures to restrict vehicle turning movements.

    DOT National Transportation Integrated Search

    2015-12-01

    This study evaluated alternatives to raised/non-traversable medians on driveways and approaches. : Raised medians are often considered as an effective technique to limit direct left-turns that may be due : to a significant number of conflict points. ...

  17. Characteristics of turn signal use at intersections in baseline naturalistic driving.

    PubMed

    Sullivan, John M; Bao, Shan; Goudy, Roy; Konet, Heather

    2015-01-01

    The purpose of this study was to determine whether a driver's use of turn signals is sufficiently reliable to forecast a vehicle's future path around an intersection, when detailed information about the intersection is unavailable. Naturalistic observations of turn signal use among 108 drivers on surface streets were extracted from the baseline portion of a field operational test of a safety system. Left and right turns that resulted in heading changes of between 70 and 110° and turn radii between 18 and 90 m were selected from the dataset. The odds that a driver would signal a turn were modeled as a function of road type, turn direction, presence of a forward vehicle, whether the vehicle stopped before the turn, and driver age and gender. Overall, 25 percent of left turns and 29 percent of right turns were not signaled. Road type, turn direction, and presence of a forward vehicle were found to influence the odds that a turn is signaled, while gender and age of the driver did not. The results suggest that situational factors like road type and turn direction are more powerful predictors of whether a turn will be signaled than either age or gender. Signaling on major and minor surface roads was about 5 times more likely than on local roads and 1.5 times more likely when a forward vehicle was present, suggesting a possible effect of traffic volume. It was concluded that turn signal activation alone may be insufficiently reliable to forecast a driver's path. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Effects of a continuous lateral turning device on pressure relief.

    PubMed

    Do, Nam Ho; Kim, Deog Young; Kim, Jung-Hoon; Choi, Jong Hyun; Joo, So Young; Kang, Na Kyung; Baek, Yoon Su

    2016-01-01

    [Purpose] The purpose of this study was to examine the pressure-relieving effects of a continuous lateral turning device on common pressure ulcer sites. [Subjects] Twenty-four healthy adults participated. [Methods] The design of our continuous lateral turning device was motivated by the need for an adequate pressure-relieving device for immobile and/or elderly people. The procedure of manual repositioning is embodied in our continuous lateral turning device. The interface pressure and time were measured, and comfort grade was evaluated during sessions of continuous lateral turning at 0°, 15°, 30°, and 45°. We quantified the pressure-relieving effect using peak pressure, mean pressure, and pressure time integration. [Results] Participants demonstrated pressure time integration values below the pressure-time threshold at 15°, 30°, and 45° at all the common pressure ulcer sites. Moreover, the most effective angles for pressure relief at the common pressure ulcer sites were 30° at the occiput, 15° at the left scapula, 45° at the right scapula, 45° at the sacrum, 15° at the right heel, and 30° at the left heel. However, angles greater than 30° induced discomfort. [Conclusion] Continuous lateral turning with our specially designed device effectively relieved the pressure of targeted sites. Moreover, the suggested angles of continuous lateral turning can be used to relieve pressure at targeted sites.

  19. Safety impact of permitting right-turn-on-red : a report to Congress

    DOT National Transportation Integrated Search

    1994-12-01

    The Energy Policy Act of 1992 required NHTSA to conduct a study of the safety impact of permitting right and left turns on red lights. The report presents a brief summary of the current status of State implementation of laws permitting right and left...

  20. Advantages in exploring a new environment with the left eye in lizards.

    PubMed

    Bonati, Beatrice; Csermely, Davide; Sovrano, Valeria Anna

    2013-07-01

    Lizards (Podarcis muralis) preferentially use the left eye during spatial exploration in a binocular condition. Here we allowed 44 adult wild lizards to explore an unknown maze for 20 min under a temporary monocular condition whilst recording their movements, particularly the direction of turns made whilst walking within the maze. Lizards with a patch on their right eye, i.e. using their left eye to monitor the environment, moved faster than lizards with a patch on their left eye when turning both leftward and rightward in a T-cross. Hence, right eye-patched lizards were faster than left eye-patched lizards also in turning right, although their right eye was covered. Thus, lizards that could use the left eye/right hemisphere to attend spatial cues appeared to have more control and to be more prompt in exploring the maze. In addition, female lizards with their left eye covered stopped very frequently when they reached crosses, showing a high level of indecision. Results confirm that P. muralis lizards using their left eye only in exploring a new environment react faster and more efficiently than those using the right eye only in exploration. Hence lateralisation of spatial stimuli mediated by the left eye/right hemisphere could provide an advantage to this species. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. No Community Left Behind

    ERIC Educational Resources Information Center

    Schlechty, Phillip C.

    2008-01-01

    The debate over the reauthorization of No Child Left Behind (NCLB) generally overlooks--or looks past--what may be the most fundamental flaw in that legislation. As the law is now written, decisions regarding what the young should know and be able to do are removed from the hands of parents and local community leaders and turned over to officials…

  2. Characterization of beta-turn and Asx-turns mimicry in a model peptide: stabilization via C--H . . . O interaction.

    PubMed

    Thakur, A K; Kishore, R

    2006-04-15

    The chemical synthesis and single-crystal X-ray diffraction analysis of a model peptide, Boc-Thr-Thr-NH2 (1) comprised of proteinogenic residues bearing an amphiphilic Cbeta -stereogenic center, has been described. Interestingly, the analysis of its molecular structure revealed the existence of a distinct conformation that mimics a typical beta-turn and Asx-turns, i.e., the two Thr residues occupy the left- and right-corner positions. The main-chain torsion angles of the N- and C-terminal residues i.e., semiextended: phi = -68.9 degrees , psi = 128.6 degrees ; semifolded: phi = -138.1 degrees , psi = 2.5 degrees conformations, respectively, in conjunction with a gauche- disposition of the obligatory C-terminus Thr CgammaH3 group, characterize the occurrence of the newly described beta-turn- and Asx-turns-like topology. The preferred molecular structure is suggested to be stabilized by an effective nonconventional main-chain to side-chain Ci=O . . . H--Cgamma(i+2)-type intraturn hydrogen bond. Noteworthy, the observed topology of the resulting 10-membered hydrogen-bonded ring is essentially similar to the one perceived for a classical beta-turn and the Asx-turns, stabilized by a conventional intraturn hydrogen bond. Considering the signs as well as magnitudes of the backbone torsion angles and the orientation of the central peptide bond, the overall mimicked topology resembles the type II beta-turn or type II Asx-turns. An analysis of Xaa-Thr sequences in high-resolution X-ray elucidated protein structures revealed the novel topology prevalence in functional proteins (unpublished). In view of indubitable structural as well as functional importance of nonconventional interactions in bioorganic and biomacromolecules, we intend to highlight the participation of Thr CgammaH in the creation of a short-range C=O . . . H--Cgamma -type interaction in peptides and proteins. Copyright 2006 Wiley Periodicals, Inc.

  3. Eye and head motion during head turns in spaceflight

    NASA Technical Reports Server (NTRS)

    Thornton, William E.; Uri, John J.; Moore, Thomas P.; Pool, Sam L.

    1988-01-01

    Eye-head motion was studied pre-, in- and postflight during single voluntary head turns. A transient increase in vestibulo-ocular reflex (VOR) gain occurred early in the flight, but later trended toward normal. This increased gain was produced by a relative increase in eye counterrotation velocity. Asymmetries in gain with right and left turns also occurred, caused by asymmetries in eye counterrotation velocities. These findings were remarkably similar to those from Soviet primate studies using gaze fixation targets, except the human study trended more rapidly toward normal. These findings differ substantially from those measuring VOR gain by head oscillation, in which no significant changes were found inflight. No visual disturbances were noted in either test condition or in normal activities. These head turn studies are the only ones to date documenting any functional change in VOR in weightlessness.

  4. Hydrogen-bonded turns in proteins: The case for a recount

    PubMed Central

    Panasik, Nick; Fleming, Patrick J.; Rose, George D.

    2005-01-01

    β-Turns are sites at which proteins change their overall chain direction, and they occur with high frequency in globular proteins. The Protein Data Bank has many instances of conformations that resemble β-turns but lack the characteristic N–H(i) → O=C(i − 3) hydrogen bond of an authentic β-turn. Here, we identify potential hydrogen-bonded β-turns in the coil library, a Web-accessible database utility comprised of all residues not in repetitive secondary structure, neither α-helix nor β-sheet (http://www.roselab.jhu.edu/coil). In particular, candidate turns were identified as four-residue segments satisfying highly relaxed geometric criteria but lacking a strictly defined hydrogen bond. Such candidates were then subjected to a minimization protocol to determine whether slight changes in torsion angles are sufficient to shift the conformation into reference-quality geometry without deviating significantly from the original structure. This approach of applying constrained minimization to known structures reveals a substantial population of previously unidentified, stringently defined, hydrogen-bonded β-turns. In particular, 33% of coil library residues were classified as β-turns prior to minimization. After minimization, 45% of such residues could be classified as β-turns, with another 8% in 310 helixes (which closely resemble type III β-turns). Of the remaining coil library residues, 37% have backbone dihedral angles in left-handed polyproline II structure. PMID:16251367

  5. Hydrogen-bonded turns in proteins: the case for a recount.

    PubMed

    Panasik, Nick; Fleming, Patrick J; Rose, George D

    2005-11-01

    Beta-turns are sites at which proteins change their overall chain direction, and they occur with high frequency in globular proteins. The Protein Data Bank has many instances of conformations that resemble beta-turns but lack the characteristic N-H(i) --> O=C(i - 3) hydrogen bond of an authentic beta-turn. Here, we identify potential hydrogen-bonded beta-turns in the coil library, a Web-accessible database utility comprised of all residues not in repetitive secondary structure, neither alpha-helix nor beta-sheet (http://www.roselab.jhu.edu/coil). In particular, candidate turns were identified as four-residue segments satisfying highly relaxed geometric criteria but lacking a strictly defined hydrogen bond. Such candidates were then subjected to a minimization protocol to determine whether slight changes in torsion angles are sufficient to shift the conformation into reference-quality geometry without deviating significantly from the original structure. This approach of applying constrained minimization to known structures reveals a substantial population of previously unidentified, stringently defined, hydrogen-bonded beta-turns. In particular, 33% of coil library residues were classified as beta-turns prior to minimization. After minimization, 45% of such residues could be classified as beta-turns, with another 8% in 3(10) helixes (which closely resemble type III beta-turns). Of the remaining coil library residues, 37% have backbone dihedral angles in left-handed polyproline II structure.

  6. A case of left inferior vena cava.

    PubMed

    Yano, R; Hayakawa, D; Emura, S; Chen, H; Ozawa, Y; Taguchi, H; Shoumura, S

    2001-12-01

    A case of left inferior vena cava (IVC) was found in a 72-year-old male cadaver during student dissection practice in 1999 at Gifu University School of Medicine. It was formed by junction of the left and right common iliac veins at the lower left corner of the 5th lumbar vertebra. This IVC (15-mm caliber) ascended 82 mm along the left side of the abdominal aorta dorsally to the ureter. Receiving the left renal vein, it became 21 mm in caliber and ran obliquely upward for 43 mm across the abdominal aorta. As soon as it received two right renal veins at the level of the 2nd lumbar vertebra, the IVC (25-mm caliber) turned directly above. The present case belongs to Type C of the classification of McClure and Butler (1925), which is based on the combinations of the left and right IVCs, and on their location relative to the ureters. The present case also belongs to Type 1 of the classification of Yoshida et al. (1981). We consider that left IVC in the present case is mainly caused by disappearance of the right supracardinal vein and persistence of the left one during the embryological development of the IVC.

  7. The impact of general permissive right and left turn on red legislation in Virginia.

    DOT National Transportation Integrated Search

    1978-01-01

    Right turn on red (RTOR) maneuvers have been permitted at signalized intersections in Virginia since 1972. However, until January 1, 1977, following a study requested by the General Assembly, the maneuver was restricted to intersections at which a si...

  8. Opportunities and limitations for intersection collision intervention-A study of real world 'left turn across path' accidents.

    PubMed

    Sander, Ulrich

    2017-02-01

    Turning across the path of oncoming vehicle accidents are frequent and dangerous. To date not many car manufacturers have introduced Automated Emergency Braking (AEB) systems addressing this type of conflict situation, but it is foreseeable that these scenarios will be part of the Euro NCAP 2020 rating. Nine out of ten collisions are caused by the driver of the turning vehicle. An AEB system evaluating the ego and conflict vehicle driver's possibilities to avoid a pending crash by either braking or steering was specified for application in various constellations of vehicle collisions. In virtual simulation, AEB system parameters were varied, covering parameters that are relevant for driver comfort such as longitudinal and lateral acceleration (to define avoidance possibilities), expected steering maneuvers to avoid conflict, and intervention response characteristics (brake delay and ramp up) to assess the safety benefit. The reference simulation showed a potential of the AEB system in the turning vehicle to avoid approximately half of the collisions. An AEB system of the straight going vehicle was less effective. The effectiveness of the turning vehicle's AEB system increases if spatial limitations for the collision-avoidance steering maneuver are known. Such information could be provided by sensors detecting free space in or around the road environment or geographical information shared via vehicle to cloud communication. AEB interventions rarely result in collision avoidance for turning vehicles with speeds above 40km/h or for straight going vehicles with speeds above 60km/h. State of the art field-of-views of forward looking sensing systems designed for AEB rear-end interventions are capable of addressing turning across path situations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Neglect severity after left and right brain damage.

    PubMed

    Suchan, Julia; Rorden, Chris; Karnath, Hans-Otto

    2012-05-01

    While unilateral spatial neglect after left brain damage is undoubtedly less common than spatial neglect after a right hemisphere lesion, it is also assumed to be less severe. Here we directly test this latter hypothesis using a continuous measure of neglect severity: the so-called Center of Cancellation (CoC). Rorden and Karnath (2010) recently validated this index for right brain damaged neglect patients. A first aim of the present study was to evaluate this new measure for spatial neglect after left brain damage. In a group of 48 left-sided stroke patients with and without neglect, a score greater than -0.086 on the Bells Test and greater than -0.024 on the Letter Cancellation Task turned out to indicate neglect behavior for acute left brain damaged patients. A second aim was to directly compare the severity of spatial neglect after left versus right brain injury by using the new CoC measure. While neglect is less frequent following left than right hemisphere injury, we found that when this symptom occurs it is of similar severity in acute left brain injury as in patients after acute right brain injury. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Evaluating the Operational Features of an Unconventional Dual-Bay U-Turn Design for Intersections.

    PubMed

    Xiang, Yun; Li, Zhibin; Wang, Wei; Chen, Jingxu; Wang, Hao; Li, Ye

    2016-01-01

    Median U-turn intersection treatment (MUTIT) has been considered an alternative measure to reduce congestion and traffic conflict at intersection areas. The MUTIT is sometimes difficult to implement in the field because it requires wide median on arterials for U-turn vehicles. The objective of this study is to introduce an unconventional U-turn treatment (UUT) for intersections which requires less median space but is also effective. The UUT has a dual-bay design with different turning radiuses for small and large vehicles. The VISSIM simulation model was developed to evaluate the operational features of the UUT. The model was calibrated using data collected from intersections in China. The capacity, delay and number of stops were evaluated and compared with the direct-left-turn (DLT) for the same intersections. The results showed that the UUT significantly improved the operations at intersection areas, especially when volume/capacity ratio is small, and ratio of left-turn to through traffic is small. With the UUT, the capacity is increased by 9.81% to 10.38%, vehicle delay is decreased by 18.5% to 40.1%, and number of stops is decreased by 23.19% to 36.62%, when volume/capacity ratio is less than 0.50. The study also found that traffic efficiency could be further improved when the UUT is designed in conjunction with signal control. In the case, the UUT plus signalized control increases the capacity by 25% to 26.02%, decreases vehicle delay by 50.5% to 55.8%, and reduces number of stops by 69.5%, compared with the traditional DLT.

  11. Time to turn the other cheek? The influence of left and right poses on perceptions of academic specialisation.

    PubMed

    Lindell, Annukka K; Savill, Nicola J

    2010-11-01

    The human face expresses emotion asymmetrically. Whereas the left cheek is more emotionally expressive, the right cheek appears more impassive, hence the appropriate cheek to put forward depends on the circumstance. Nicholls, Clode, Wood, and Wood (1999, Proceedings of the Royal Society (Section B), 266, 1517-1522) demonstrated that people posing for family portraits offer the left cheek, whereas those posing as a Royal Society scientist favour the right. Given that the stereotypical representations of members of different academic disciplines differ markedly in their perceived openness and emotionality (e.g., "serious" scientist vs. "creative" writer), we reasoned that people may use cheek as a cue when determining a model's area of academic interest. Two hundred and nine participants (M=90, F=119) viewed pairs of left and right cheek poses, and made a forced-choice decision indicating which image depicted a Chemistry, Psychology or English student. Half the images were mirror-reversed to control for perceptual and aesthetic biases. Consistent with prediction, participants were more likely to select left cheek images for English students, and right cheek images for Chemistry students, irrespective of image orientation. The results confirm that determining the best cheek to put forward depends on your academic expertise: an impassive right cheek suggests hard science, whereas an emotive left cheek implies the arts. Psychology produced no left or right bias, consistent with its position as a discipline perpetually straddling the boundary between art and science.

  12. Evaluating the Operational Features of an Unconventional Dual-Bay U-Turn Design for Intersections

    PubMed Central

    Xiang, Yun; Li, Zhibin; Wang, Wei; Chen, Jingxu; Wang, Hao; Li, Ye

    2016-01-01

    Median U-turn intersection treatment (MUTIT) has been considered an alternative measure to reduce congestion and traffic conflict at intersection areas. The MUTIT is sometimes difficult to implement in the field because it requires wide median on arterials for U-turn vehicles. The objective of this study is to introduce an unconventional U-turn treatment (UUT) for intersections which requires less median space but is also effective. The UUT has a dual-bay design with different turning radiuses for small and large vehicles. The VISSIM simulation model was developed to evaluate the operational features of the UUT. The model was calibrated using data collected from intersections in China. The capacity, delay and number of stops were evaluated and compared with the direct-left-turn (DLT) for the same intersections. The results showed that the UUT significantly improved the operations at intersection areas, especially when volume/capacity ratio is small, and ratio of left-turn to through traffic is small. With the UUT, the capacity is increased by 9.81% to 10.38%, vehicle delay is decreased by 18.5% to 40.1%, and number of stops is decreased by 23.19% to 36.62%, when volume/capacity ratio is less than 0.50. The study also found that traffic efficiency could be further improved when the UUT is designed in conjunction with signal control. In the case, the UUT plus signalized control increases the capacity by 25% to 26.02%, decreases vehicle delay by 50.5% to 55.8%, and reduces number of stops by 69.5%, compared with the traditional DLT. PMID:27467127

  13. A Driving Simulator Evaluation of Red Arrows and Flashing Yellow Arrows in Right-Turn Applications : Establishing the Foundation for Future Research

    DOT National Transportation Integrated Search

    2017-11-01

    Driver understanding of flashing yellow arrow (FYA) indications for left turns has been studied extensively; however, the use of FYA for right-turn applications is an area that needs to be better understood through evaluations focused on actual drive...

  14. Kinematics and muscle activity of the head, lumbar and knee joints during 180° turning and sitting down task in older adults.

    PubMed

    Kuo, Fang-Chuan; Hong, Chang-Zern; Liau, Ben-Yi

    2014-01-01

    The "180° turning and sitting down task" is a very conscious movement that requires focusing on turning at the exact moment, and very few studies address on this topic in older adults. The purpose of the study was to compare kinematics and electromyography of the head, lumbar and knee joints during 180°turning in older and young adults. Twenty older adults and 20 younger adults were assessed. A 16-channel telemetry electromyography system with electrogoniometers and an inclinometer were used to record the head, lumbar and knee joint kinematic and electromyography data during the 180° turning. This movement had been further divided into 4 phases (braking, mid-stance, swing, and terminal loading) for analysis. There were significant differences in the joint displacement and muscular activity among the different phases. Comparison between groups showed that the older adults group had less lateral lumbar flexion, less knee flexion and lower velocity of the head and knee flexion compared to young adults during turning. The electromyography data of the left biceps femoris, left gastrocnemius and left erector spinae muscles in the older adults group showed significantly higher levels than in the young adults. Older adults need to adjust velocities of moving joints and increase the extensor synergy muscles of the back and the stance leg to provide posture stability. Kinematics and neuromuscular modulations of the head, lumbar and knee are required according to the various phases of the turn movements and change with aging. © 2013.

  15. Ribbon structure stabilized by C10 and C12 turns in αγ hybrid peptide.

    PubMed

    Wani, Naiem Ahmad; Kant, Rajni; Gupta, Vivek Kumar; Aravinda, Subrayashastry; Rai, Rajkishor

    2016-04-01

    The present study describes the synthesis and crystallographic analysis of αγ hybrid peptides, Boc-Gpn-L-Pro-NHMe (1), Boc-Aib-Gpn-L-Pro-NHMe (2), and Boc-L-Pro-Aib-Gpn-L-Pro-NHMe (3). Peptides 1 and 2 adopt expanded 12-membered (C12 ) helical turn over γα segment. Peptide 3 promotes the ribbon structure stabilized by type II β-turn (C10 ) followed by the expanded C12 helical γα turn. Both right-handed and left-handed helical conformations for Aib residue are observed in peptides 2 and 3, respectively. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd.

  16. Lattice Calibration with Turn-By-Turn BPM Data

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

    Huang, Xiaobiao; /SLAC; Sebek, James

    2012-07-02

    Turn-by-turn beam position monitor (BPM) data from multiple BPMs are fitted with a tracking code to calibrate magnet strengths in a manner similar to the well known LOCO code. Simulation shows that this turn-by-turn method can be a quick and efficient way for optics calibration. The method is applicable to both linacs and ring accelerators. Experimental results for a section of the SPEAR3 ring is also shown.

  17. The Clinical Significance Of Freezing While Turning in Parkinson’s Disease

    PubMed Central

    Mancini, Martina; Smulders, Katrijn; Cohen, Rajal G.; Horak, Fay B.; Giladi, Nir; Nutt, John G

    2016-01-01

    Freezing of gait (FoG) in people with Parkinson’s disease (PD) is an environmentally sensitive, intermittent problem that occurs most often during turning. FoG is difficult for clinicians to evaluate and treat because it can be difficult to elicit during a clinical visit. Here, we aimedto develop a clinically valid objective measure of freezing severity during a 2-minute 360 degrees turning-in-place. Twenty-eight subjects with PD (16 freezers, FoG+, and 12 nonfreezers, FoG−) in the “off” state and 14 healthy control subjects were tested. Subjects wore 3 inertial sensors (one on each shin and one on the waist) while 1) turning in place for 2 minutes (alternating 360 degrees to the right with 360 degrees to the left) and 2) performing an Instrumented 7m Timed Up and Go test (ITUG). Performance was videotaped, and clinical severity of FoG was independently rated by two movement disorders specialists (co-authors). Turning in place consistently resulted in FoG (13 out of 16 subjects with PD) while FoG was clinically observed in only 2 subjects with PD during the ITUG test. The Freezing Ratio during the turning test was significantly correlated with the clinical ratings (ρ=0.7, p=0.003) and with score on the new freezing of gait questionnaire (ρ=0.5, p=0.03). After correcting for symptom severity (UPDRS-III), out of the 4 objective measures of the turning test (total number of turns, average turn peak speed and average turn smoothness), only the Freezing Ratio was significantly different across groups (p=0.04). Freezing can be well quantified with body-worn inertial sensors during a 2-minute turning-in-place protocol. PMID:27956066

  18. [Abnormal head turn in a patient with Brown's syndrome].

    PubMed

    van Waveren, M; Krzizok, T; Besch, D

    2008-08-01

    We report on an eight-year-old boy, who was presented in our clinic because of head turn. The cause of the tortecollis (ocular or general) in this case was and still cannot be explained. Only by applying extensive prism adaptation tests it was possible to prove the ocular character of the head turn. An eight-year-old boy with Brown's syndrome was referred to us because of a head tilt to the left side. Six months previously surgery on the M. obl. superior of the right eye was performed in another clinic. No improvement of the head tilt could be observed after the operation. In addition, an exotropia became decompensated. Under a 3-day occlusion of one eye, no change of the head turn and the squint could be measured. No other cause of the head turn could be found by an orthopaedist and a paediatrist. Under a prism of 20 cm/m basis in and 10 cm/m basis against the positive vertical deviation, the head tilt decreased, so that we decided to do a second surgery. The head tilting had not resumed at one year after the surgery. Although the initial diagnostic findings ruled out an ocular cause, it was possible to lessen the head tilting with the aid of the prism adaptation test. This case study emphasises the usefulness of a prism adaptation test of several days duration in order to validate an ocular cause of head turn and to determine an adequate indication for surgery.

  19. 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.

  20. High salt solution structure of a left-handed RNA double helix

    PubMed Central

    Popenda, Mariusz; Milecki, Jan; Adamiak, Ryszard W.

    2004-01-01

    Right-handed RNA duplexes of (CG)n sequence undergo salt-induced helicity reversal, forming left-handed RNA double helices (Z-RNA). In contrast to the thoroughly studied Z-DNA, no Z-RNA structure of natural origin is known. Here we report the NMR structure of a half-turn, left-handed RNA helix (CGCGCG)2 determined in 6 M NaClO4. This is the first nucleic acid motif determined at such high salt. Sequential assignments of non-exchangeable proton resonances of the Z-form were based on the hitherto unreported NOE connectivity path [H6(n)-H5′/H5″(n)-H8(n+1)-H1′(n+1)-H6(n+2)] found for left-handed helices. Z-RNA structure shows several conformational features significantly different from Z-DNA. Intra-strand but no inter-strand base stacking was observed for both CpG and GpC steps. Helical twist angles for CpG steps have small positive values (4–7°), whereas GpC steps have large negative values (−61°). In the full-turn model of Z-RNA (12.4 bp per turn), base pairs are much closer to the helix axis than in Z-DNA, thus both the very deep, narrow minor groove with buried cytidine 2′-OH groups, and the major groove are well defined. The 2′-OH group of cytidines plays a crucial role in the Z-RNA structure and its formation; 2′-O-methylation of cytidine, but not of guanosine residues prohibits A to Z helicity reversal. PMID:15292450

  1. Turn-Taking, Turn-Giving, and Alzheimer's Disease.

    ERIC Educational Resources Information Center

    Sabat, Steven R.

    1991-01-01

    Analysis of a conversation with an Alzheimer's disease sufferer with word-finding problems revealed that social context, speaker characteristics, and awareness of the other speaker's perspective governed such conversational aspects of turn taking and turn giving, which allowed full development of both speakers' personas. (23 references) (CB)

  2. Micro-simulation of vehicle conflicts involving right-turn vehicles at signalized intersections based on cellular automata.

    PubMed

    Chai, C; Wong, Y D

    2014-02-01

    At intersection, vehicles coming from different directions conflict with each other. Improper geometric design and signal settings at signalized intersection will increase occurrence of conflicts between road users and results in a reduction of the safety level. This study established a cellular automata (CA) model to simulate vehicular interactions involving right-turn vehicles (as similar to left-turn vehicles in US). Through various simulation scenarios for four case cross-intersections, the relationships between conflict occurrences involving right-turn vehicles with traffic volume and right-turn movement control strategies are analyzed. Impacts of traffic volume, permissive right-turn compared to red-amber-green (RAG) arrow, shared straight-through and right-turn lane as well as signal setting are estimated from simulation results. The simulation model is found to be able to provide reasonable assessment of conflicts through comparison of existed simulation approach and observed accidents. Through the proposed approach, prediction models for occurrences and severity of vehicle conflicts can be developed for various geometric layouts and traffic control strategies. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Modeling left turn queue lengths.

    DOT National Transportation Integrated Search

    2011-01-01

    This guidebook provides methodologies and procedures for using incident data collected at Texas transportation management centers (TMCs) to perform two types of analysis - evaluation/planning analysis and predictive analysis. For the evaluation/plann...

  4. Removal of single point diamond-turning marks by abrasive jet polishing.

    PubMed

    Li, Z Z; Wang, J M; Peng, X Q; Ho, L T; Yin, Z Q; Li, S Y; Cheung, C F

    2011-06-01

    Single point diamond turning (SPDT) is highly controllable and versatile in producing axially symmetric forms, non-axially-symmetric forms, microstructured surfaces, and free forms. However, the fine SPDT marks left in the surface limit its performance, and they are difficult to reduce or eliminate. It is unpractical for traditional methods to remove the fine marks without destroying their forms, especially for the aspheres and free forms. This paper introduces abrasive jet polishing (AJP) for the posttreatment of diamond-turned surfaces to remove the periodic microstructures. Samples of diamond-turned electroless nickel plated plano mirror were used in the experiments. One sample with an original surface roughness of more than 400 nm decreased to 4 nm after two iterations abrasive jet polishing; the surface roughness of another sample went from 3.7 nm to 1.4 nm after polishing. The periodic signatures on both of the samples were removed entirely after polishing. Contrastive experimental research was carried out on electroless nickel mirror with magnetorheological finishing, computer controlled optical surfacing, and AJP. The experimental results indicate that AJP is more appropriate in removing the periodic SPDT marks. Also, a figure maintaining experiment was carried out with the AJP process; the uniform polishing process shows that the AJP process can remove the periodic turning marks without destroying the original form.

  5. [Selective left mainstem bronchial intubation in the neonatal intensive care unit].

    PubMed

    Ho, Anthony M H; Flavin, Michael P; Fleming, Melinda L; Mizubuti, Glenio Bitencourt

    Selective neonatal left mainstem bronchial intubation to treat right lung disease is typically achieved with elaborate maneuvers, instrumentation and devices. This is often attributed to bronchial geometry which favors right mainstem entry of an endotracheal tube deliberately advanced beyond the carina. A neonate with severe bullous emphysema affecting the right lung required urgent non-ventilation of that lung. We achieved left mainstem bronchial intubation by turning the endotracheal tube 180° such that the Murphy's eye faced the left instead of the right, and simulated a left-handed intubation by slightly orientating the endotracheal tube such that its concavity faced the left instead of the right as in a conventional right-handed intubation. Urgent intubation of the left mainstem bronchus with an endotracheal tube can be easily achieved by recognizing that it is the position of the endotracheal tube tip and the direction of its concavity that are the chief determinants of which bronchus an endotracheal tube goes when advanced. This is important in critically ill neonates as the margin of safety and time window are small, and the absence of double-lumen tubes. Use of fiberoptic bronchoscope and blockers should be reserved as backup plans. Copyright © 2017 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

  6. Turning assistive machines into assistive robots

    NASA Astrophysics Data System (ADS)

    Argall, Brenna D.

    2015-01-01

    For decades, the potential for automation in particular, in the form of smart wheelchairs to aid those with motor, or cognitive, impairments has been recognized. It is a paradox that often the more severe a person's motor impairment, the more challenging it is for them to operate the very assistive machines which might enhance their quality of life. A primary aim of my lab is to address this confound by incorporating robotics autonomy and intelligence into assistive machines turning the machine into a kind of robot, and offloading some of the control burden from the user. Robots already synthetically sense, act in and reason about the world, and these technologies can be leveraged to help bridge the gap left by sensory, motor or cognitive impairments in the users of assistive machines. This paper overviews some of the ongoing projects in my lab, which strives to advance human ability through robotics autonomy.

  7. Turning the School Around: The Transformation of a Secondary School from Underperforming to Highly Achieving

    ERIC Educational Resources Information Center

    Branch, Cynthia Monroe

    2013-01-01

    The No Child Left Behind Act of 2001 put a focus on each child in a school being proficient. Since 1957 when Sputnik was launched, the United States has been attempting to improve its schools. The existing literature has a gap as to how to turn around an underperforming school in a fairly short period of time. A qualitative case study methodology…

  8. Tune Evaluation From Phased BPM Turn-By-Turn Data

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

    Alexahin, Y.; Gianfelice-Wendt, E.; Marsh, W.

    2010-05-18

    In fast ramping synchrotrons like the Fermilab Booster the conventional methods of betatron tune evaluation from the turn-by-turn data may not work due to rapid changes of the tunes (sometimes in a course of a few dozens of turns) and a high level of noise. We propose a technique based on phasing of signals from a large number of BPMs which significantly increases the signal to noise ratio. Implementation of the method in the Fermilab Booster control system is described and some measurement results are presented.

  9. The performance of the standard rate turn (SRT) by student naval helicopter pilots.

    PubMed

    Chapman, F; Temme, L A; Still, D L

    2001-04-01

    During flight training, student naval helicopter pilots learn the use of flight instruments through a prescribed series of simulator training events. The training simulator is a 6-degrees-of-freedom, motion-based, high-fidelity instrument trainer. From the final basic instrument simulator flights of student pilots, we selected for evaluation and analysis their performance of the Standard Rate Turn (SRT), a routine flight maneuver. The performance of the SRT was scored with air speed, altitude and heading average error from target values and standard deviations. These average errors and standard deviations were used in a Multiple Analysis of Variance (MANOVA) to evaluate the effects of three independent variables: 1) direction of turn (left vs. right), 2) degree of turn (180 vs. 360 degrees); and 3) segment of turn (roll-in, first 30 s, last 30 s, and roll-out of turn). Only the main effects of the three independent variables were significant; there were no significant interactions. This result greatly reduces the number of different conditions that should be scored separately for the evaluation of SRT performance. The results also showed that the magnitude of the heading and altitude errors at the beginning of the SRT correlated with the magnitude of the heading and altitude errors throughout the turn. This result suggests that for the turn to be well executed, it is important for it to begin with little error in these two response parameters. The observations reported here should be considered when establishing SRT performance norms and comparing student scores. Furthermore, it seems easier for pilots to maintain good performance than to correct poor performance.

  10. Causal Role of Motor Simulation in Turn-Taking Behavior.

    PubMed

    Hadley, Lauren V; Novembre, Giacomo; Keller, Peter E; Pickering, Martin J

    2015-12-16

    Overlap between sensory and motor representations has been documented for a range of human actions, from grasping (Rizzolatti et al., 1996b) to playing a musical instrument (Novembre and Keller, 2014). Such overlap suggests that individuals use motor simulation to predict the outcome of observed actions (Wolpert, 1997). Here we investigate motor simulation as a basis of human communication. Using a musical turn-taking task, we show that pianists call on motor representations of their partner's part to predict when to come in for their own turn. Pianists played alternating solos with a videoed partner, and double-pulse transcranial magnetic stimulation was applied around the turn-switch to temporarily disrupt processing in two cortical regions implicated previously in different forms of motor simulation: (1) the dorsal premotor cortex (dPMC), associated with automatic motor resonance during passive observation of hand actions, especially when the actions are familiar (Lahav et al., 2007); and (2) the supplementary motor area (SMA), involved in active motor imagery, especially when the actions are familiar (Baumann et al., 2007). Stimulation of the right dPMC decreased the temporal accuracy of pianists' (right-hand) entries relative to sham when the partner's (left-hand) part had been rehearsed previously. This effect did not occur for dPMC stimulation without rehearsal or for SMA stimulation. These findings support the role of the dPMC in predicting the time course of observed actions via resonance-based motor simulation during turn-taking. Because turn-taking spans multiple modes of human interaction, we suggest that simulation is a foundational mechanism underlying the temporal dynamics of joint action. Even during passive observation, seeing or hearing somebody execute an action from within our repertoire activates motor cortices of our brain. But what is the functional relevance of such "motor simulation"? By combining a musical duet task with a real

  11. Rhynchophylline from Uncaria rhynchophylla functionally turns delayed rectifiers into A-Type K+ channels.

    PubMed

    Chou, Chun-Hsiao; Gong, Chi-Li; Chao, Chia-Chia; Lin, Chia-Huei; Kwan, Chiu-Yin; Hsieh, Ching-Liang; Leung, Yuk-Man

    2009-05-22

    Rhynchophylline (1), a neuroprotective agent isolated from the traditional Chinese medicinal herb Uncaria rhynchophylla, was shown to affect voltage-gated K(+) (Kv) channel slow inactivation in mouse neuroblastoma N2A cells. Extracellular 1 (30 microM) accelerated the slow decay of Kv currents and shifted the steady-state inactivation curve to the left. Intracellular dialysis of 1 did not accelerate the slow current decay, suggesting that this compound acts extracellularly. In addition, the percent blockage of Kv currents by this substance was independent of the degree of depolarization and the intracellular K(+) concentration. Therefore, 1 did not appear to directly block the outer channel pore, with the results obtained suggesting that it drastically accelerated Kv channel slow inactivation. Interestingly, 1 also shifted the activation curve to the left. This alkaloid also strongly accelerated slow inactivation and caused a left shift of the activation curve of Kv1.2 channels heterologously expressed in HEK293 cells. Thus, this compound functionally turned delayed rectifiers into A-type K(+) channels.

  12. Induction motor inter turn fault detection using infrared thermographic analysis

    NASA Astrophysics Data System (ADS)

    Singh, Gurmeet; Anil Kumar, T. Ch.; Naikan, V. N. A.

    2016-07-01

    Induction motors are the most commonly used prime movers in industries. These are subjected to various environmental, thermal and load stresses that ultimately reduces the motor efficiency and later leads to failure. Inter turn fault is the second most commonly observed faults in the motors and is considered the most severe. It can lead to the failure of complete phase and can even cause accidents, if left undetected or untreated. This paper proposes an online and non invasive technique that uses infrared thermography, in order to detect the presence of inter turn fault in induction motor drive. Two methods have been proposed that detect the fault and estimate its severity. One method uses transient thermal monitoring during the start of motor and other applies pseudo coloring technique on infrared image of the motor, after it reaches a thermal steady state. The designed template for pseudo-coloring is in acquiescence with the InterNational Electrical Testing Association (NETA) thermographic standard. An index is proposed to assess the severity of the fault present in the motor.

  13. Lattice modeling and calibration with turn-by-turn orbit data

    NASA Astrophysics Data System (ADS)

    Huang, Xiaobiao; Sebek, Jim; Martin, Don

    2010-11-01

    A new method that explores turn-by-turn beam position monitor (BPM) data to calibrate lattice models of accelerators is proposed. The turn-by-turn phase space coordinates at one location of the ring are first established using data from two BPMs separated by a simple section with a known transfer matrix, such as a drift space. The phase space coordinates are then tracked with the model to predict positions at other BPMs, which can be compared to measurements. The model is adjusted to minimize the difference between the measured and predicted orbit data. BPM gains and rolls are included as fitting variables. This technique can be applied to either the entire or a section of the ring. We have tested the method experimentally on a part of the SPEAR3 ring.

  14. Turn Basin Construction

    NASA Image and Video Library

    2017-06-14

    Modifications are underway at the Launch Complex 39 turn basin wharf at NASA's Kennedy Space Center in Florida to prepare for the arrival of the agency's massive Space Launch System (SLS) core booster aboard the barge Pegasus. Construction workers with Southeast Cherokee Construction Inc. work to shore up the turn basin area. A crane will be used to lift up precast concrete poles and position them to be driven to a depth of about 70 feet into the bedrock below the water around the turn basin. The upgrades are necessary to accommodate the 300,000-pound core booster aboard the modified Pegasus barge. The Ground Systems Development and Operations Program is overseeing the upgrades to the turn basin wharf.

  15. Mimicry by asx- and ST-turns of the four main types of beta-turn in proteins.

    PubMed

    Duddy, William J; Nissink, J Willem M; Allen, Frank H; Milner-White, E James

    2004-11-01

    Hydrogen-bonded beta-turns in proteins occur in four categories: type I (the most common), type II, type II', and type I'. Asx-turns resemble beta-turns, in that both have an NH. . .OC hydrogen bond forming a ring of 10 atoms. Serine and threonine side chains also commonly form hydrogen-bonded turns, here called ST-turns. Asx-turns and ST-turns can be categorized into four classes, based on side chain rotamers and the conformation of the central turn residue, which are geometrically equivalent to the four types of beta-turns. We propose asx- and ST-turns be named using the type I, II, I', and II' beta-turn nomenclature. Using this, the frequency of occurrence of both asx- and ST-turns is: type II' > type I > type II > type I', whereas for beta-turns it is type I > type II > type I' > type II'. Almost all type II asx-turns occur as a recently described three residue feature named an asx-nest.

  16. Mimicry by asx- and ST-turns of the four main types of β-turn in proteins

    PubMed Central

    Duddy, William J.; Nissink, J. Willem M.; Allen, Frank H.; Milner-White, E. James

    2004-01-01

    Hydrogen-bonded β-turns in proteins occur in four categories: type I (the most common), type II, type II’, and type I’. Asx-turns resemble β-turns, in that both have an NH. . .OC hydrogen bond forming a ring of 10 atoms. Serine and threonine side chains also commonly form hydrogen-bonded turns, here called ST-turns. Asx-turns and ST-turns can be categorized into four classes, based on side chain rotamers and the conformation of the central turn residue, which are geometrically equivalent to the four types of β-turns. We propose asx- and ST-turns be named using the type I, II, I’, and II’ β-turn nomenclature. Using this, the frequency of occurrence of both asx- and ST-turns is: type II’ > type I > type II > type I’, whereas for β-turns it is type I > type II > type I’ > type II’. Almost all type II asx-turns occur as a recently described three residue feature named an asx-nest. PMID:15459339

  17. Age-related modifications in steering behaviour: effects of base-of-support constraints at the turn point.

    PubMed

    Paquette, Maxime R; Fuller, Jason R; Adkin, Allan L; Vallis, Lori Ann

    2008-09-01

    This study investigated the effects of altering the base of support (BOS) at the turn point on anticipatory locomotor adjustments during voluntary changes in travel direction in healthy young and older adults. Participants were required to walk at their preferred pace along a 3-m straight travel path and continue to walk straight ahead or turn 40 degrees to the left or right for an additional 2-m. The starting foot and occasionally the gait starting point were adjusted so that participants had to execute the turn using a cross-over step with a narrow BOS or a lead-out step with a wide BOS. Spatial and temporal gait variables, magnitudes of angular segmental movement, and timing and sequencing of body segment reorientation were similar despite executing the turn with a narrow or wide BOS. A narrow BOS during turning generated an increased step width in the step prior to the turn for both young and older adults. Age-related changes when turning included reduced step velocity and step length for older compared to young adults. Age-related changes in the timing and sequencing of body segment reorientation prior to the turn point were also observed. A reduction in walking speed and an increase in step width just prior to the turn, combined with a delay in motion of the center of mass suggests that older adults used a more cautious combined foot placement and hip strategy to execute changes in travel direction compared to young adults. The results of this study provide insight into mobility constraints during a common locomotor task in older adults.

  18. Cerberus-Nodal-Lefty-Pitx signaling cascade controls left-right asymmetry in amphioxus.

    PubMed

    Li, Guang; Liu, Xian; Xing, Chaofan; Zhang, Huayang; Shimeld, Sebastian M; Wang, Yiquan

    2017-04-04

    Many bilaterally symmetrical animals develop genetically programmed left-right asymmetries. In vertebrates, this process is under the control of Nodal signaling, which is restricted to the left side by Nodal antagonists Cerberus and Lefty. Amphioxus, the earliest diverging chordate lineage, has profound left-right asymmetry as a larva. We show that Cerberus , Nodal , Lefty , and their target transcription factor Pitx are sequentially activated in amphioxus embryos. We then address their function by transcription activator-like effector nucleases (TALEN)-based knockout and heat-shock promoter (HSP)-driven overexpression. Knockout of Cerberus leads to ectopic right-sided expression of Nodal , Lefty , and Pitx , whereas overexpression of Cerberus represses their left-sided expression. Overexpression of Nodal in turn represses Cerberus and activates Lefty and Pitx ectopically on the right side. We also show Lefty represses Nodal , whereas Pitx activates Nodal These data combine in a model in which Cerberus determines whether the left-sided gene expression cassette is activated or repressed. These regulatory steps are essential for normal left-right asymmetry to develop, as when they are disrupted embryos may instead form two phenotypic left sides or two phenotypic right sides. Our study shows the regulatory cassette controlling left-right asymmetry was in place in the ancestor of amphioxus and vertebrates. This includes the Nodal inhibitors Cerberus and Lefty, both of which operate in feedback loops with Nodal and combine to establish asymmetric Pitx expression. Cerberus and Lefty are missing from most invertebrate lineages, marking this mechanism as an innovation in the lineage leading to modern chordates.

  19. Turning breech babies after 34 weeks: the if, how, & when of turning breech babies.

    PubMed

    Cohain, Judy Slome

    2007-01-01

    Techniques for turning a term breech baby are 1). External cephalic version (ECV) using hands and ultrasound only; 2). Acupuncture point stimulation, by needle or moxibustion; 3). Chiropractic "Webster" technique; 4). Hypnotherapy; and 5). Special exercises. Fifty % of breech fetuses at 34 weeks will turn by themselves to head down by 38 weeks. Therefore, to be considered effective, a technique for turning breech must turn the baby and keep it turned more than 50% of the time. Only ECV with an experienced practitioner has been documented to have a greater than 50% success rate at 37 weeks; in 95% of cases the head stays down. Most women experience the fetus turning by hand as quick but very painful. "Unstable lie" is sometimes used as a baseless excuse for inducing labor after the baby turns from breech to head down. (judyslome@hotmail.com).

  20. Turn Basin Construction

    NASA Image and Video Library

    2017-06-14

    Modifications are underway at the Launch Complex 39 turn basin wharf at NASA's Kennedy Space Center in Florida to prepare for the arrival of the agency's massive Space Launch System (SLS) core stage aboard the barge Pegasus. Precast concrete poles are being driven to a depth of about 70 feet into the bedrock below the water around the turn basin. The upgrades are necessary to accommodate the increased weight of the core stage along with ground support and transportation equipment aboard the modified barge Pegasus. The Ground Systems Development and Operations Program is overseeing the upgrades to the turn basin wharf.

  1. Determination of linear optics functions from turn-by-turn data

    NASA Astrophysics Data System (ADS)

    Alexahin, Y.; Gianfelice-Wendt, E.

    2011-10-01

    A method for evaluation of coupled optics functions, detection of strong perturbing elements, determination of BPM calibration errors and tilts using turn-by-turn (TBT) data is presented as well as the new version of the Hamiltonian perturbation theory of betatron oscillations the method is based upon. An example of application of the considered method to the Tevatron is given.

  2. Turn Basin Construction

    NASA Image and Video Library

    2017-06-14

    Modifications are underway at the Launch Complex 39 turn basin wharf at NASA's Kennedy Space Center in Florida to prepare for the arrival of the agency's massive Space Launch System (SLS) core stage aboard the barge Pegasus. A crane will be used to lift up precast concrete poles and position them to be driven to a depth of about 70 feet into the bedrock below the water around the turn basin. The upgrades are necessary to accommodate the 300,000-pound core booster aboard the modified Pegasus barge. The Ground Systems Development and Operations Program is overseeing the upgrades to the turn basin wharf.

  3. Measuring zebrafish turning rate.

    PubMed

    Mwaffo, Violet; Butail, Sachit; di Bernardo, Mario; Porfiri, Maurizio

    2015-06-01

    Zebrafish is becoming a popular animal model in preclinical research, and zebrafish turning rate has been proposed for the analysis of activity in several domains. The turning rate is often estimated from the trajectory of the fish centroid that is output by commercial or custom-made target tracking software run on overhead videos of fish swimming. However, the accuracy of such indirect methods with respect to the turning rate associated with changes in heading during zebrafish locomotion is largely untested. Here, we compare two indirect methods for the turning rate estimation using the centroid velocity or position data, with full shape tracking for three different video sampling rates. We use tracking data from the overhead video recorded at 60, 30, and 15 frames per second of zebrafish swimming in a shallow water tank. Statistical comparisons of absolute turning rate across methods and sampling rates indicate that, while indirect methods are indistinguishable from full shape tracking, the video sampling rate significantly influences the turning rate measurement. The results of this study can aid in the selection of the video capture frame rate, an experimental design parameter in zebrafish behavioral experiments where activity is an important measure.

  4. Turn Basin Construction

    NASA Image and Video Library

    2017-06-14

    Modifications are underway at the Launch Complex 39 turn basin wharf at NASA's Kennedy Space Center in Florida to prepare for the arrival of the agency's massive Space Launch System (SLS) core stage aboard the barge Pegasus. Equipment is staged and a crane will be used to lift up precast concrete poles and position them to be driven to a depth of about 70 feet into the bedrock below the water around the turn basin. The upgrades are necessary to accommodate the increased weight of the core stage along with ground support and transportation equipment aboard the modified barge Pegasus. The Ground Systems Development and Operations Program is overseeing the upgrades to the turn basin wharf.

  5. Turn Basin Construction

    NASA Image and Video Library

    2017-06-14

    Modifications are underway at the Launch Complex 39 turn basin wharf at NASA's Kennedy Space Center in Florida to prepare for the arrival of the agency's massive Space Launch System (SLS) core stage aboard the barge Pegasus. A crane will be used to lift up precast concrete poles and position them to be driven to a depth of about 70 feet into the bedrock below the water around the turn basin. The upgrades are necessary to accommodate the increased weight of the core stage along with ground support and transportation equipment aboard the modified barge Pegasus. The Ground Systems Development and Operations Program is overseeing the upgrades to the turn basin wharf.

  6. Peptide design using alpha,beta-dehydro amino acids: from beta-turns to helical hairpins.

    PubMed

    Mathur, Puniti; Ramakumar, S; Chauhan, V S

    2004-01-01

    Incorporation of alpha,beta-dehydrophenylalanine (DeltaPhe) residue in peptides induces folded conformations: beta-turns in short peptides and 3(10)-helices in larger ones. A few exceptions-namely, alpha-helix or flat beta-bend ribbon structures-have also been reported in a few cases. The most favorable conformation of DeltaPhe residues are (phi,psi) approximately (-60 degrees, -30 degrees ), (-60 degrees, 150 degrees ), (80 degrees, 0 degrees ) or their enantiomers. DeltaPhe is an achiral and planar residue. These features have been exploited in designing DeltaPhe zippers and helix-turn-helix motifs. DeltaPhe can be incorporated in both right and left-handed helices. In fact, consecutive occurrence of three or more DeltaPhe amino acids induce left-handed screw sense in peptides containing L-amino acids. Weak interactions involving the DeltaPhe residue play an important role in molecular association. The C--H.O==C hydrogen bond between the DeltaPhe side-chain and backbone carboxyl moiety, pi-pi stacking interactions between DeltaPhe side chains belonging to enantiomeric helices have shown to stabilize folding. The unusual capability of a DeltaPhe ring to form the hub of multicentered interactions namely, a donor in aromatic C--H.pi and C--H.O==C and an acceptor in a CH(3).pi interaction suggests its exploitation in introducing long-range interactions in the folding of supersecondary structures. Copyright 2004 Wiley Periodicals, Inc. Biopolymers (Pept Sci), 2004

  7. Turn Basin Construction

    NASA Image and Video Library

    2017-06-14

    Modifications are underway at the Launch Complex 39 turn basin wharf at NASA's Kennedy Space Center in Florida to prepare for the arrival of the agency's massive Space Launch System (SLS) core stage aboard the barge Pegasus. In the foreground is Tammy Kelly, site manager, with Southeast Cherokee Construction Inc. A crane will be used to lift up precast concrete poles and position them to be driven to a depth of about 70 feet into the bedrock below the water around the turn basin. The upgrades are necessary to accommodate the increased weight of the core stage along with ground support and transportation equipment aboard the modified barge Pegasus. The Ground Systems Development and Operations Program is overseeing the upgrades to the turn basin wharf.

  8. Immediate Effects of Clock-Turn Strategy on the Pattern and Performance of Narrow Turning in Persons With Parkinson Disease.

    PubMed

    Yang, Wen-Chieh; Hsu, Wei-Li; Wu, Ruey-Meei; Lin, Kwan-Hwa

    2016-10-01

    Turning difficulty is common in people with Parkinson disease (PD). The clock-turn strategy is a cognitive movement strategy to improve turning performance in people with PD despite its effects are unverified. Therefore, this study aimed to investigate the effects of the clock-turn strategy on the pattern of turning steps, turning performance, and freezing of gait during a narrow turning, and how these effects were influenced by concurrent performance of a cognitive task (dual task). Twenty-five people with PD were randomly assigned to the clock-turn or usual-turn group. Participants performed the Timed Up and Go test with and without concurrent cognitive task during the medication OFF period. The clock-turn group performed the Timed Up and Go test using the clock-turn strategy, whereas participants in the usual-turn group performed in their usual manner. Measurements were taken during the 180° turn of the Timed Up and Go test. The pattern of turning steps was evaluated by step time variability and step time asymmetry. Turning performance was evaluated by turning time and number of turning steps. The number and duration of freezing of gait were calculated by video review. The clock-turn group had lower step time variability and step time asymmetry than the usual-turn group. Furthermore, the clock-turn group turned faster with fewer freezing of gait episodes than the usual-turn group. Dual task increased the step time variability and step time asymmetry in both groups but did not affect turning performance and freezing severity. The clock-turn strategy reduces turning time and freezing of gait during turning, probably by lowering step time variability and asymmetry. Dual task compromises the effects of the clock-turn strategy, suggesting a competition for attentional resources.Video Abstract available for more insights from the authors (see Supplemental Digital Content 1, http://links.lww.com/JNPT/A141).

  9. Compound measure of hand-foot-eye preference masked opposite turning behavior in healthy right-handers and non-right-handers: technical comment on Mohr et al. (2003).

    PubMed

    Mohr, C; Bracha, H S

    2004-10-01

    A previous article reported opposite turning behavior in right-handers and non-right-handers (C. Mohr. T. Landis, H. S. Bracha, & P. Brugger, 2003). This observation appears contradictory to the 1st study on long-term spontaneous turning behavior in healthy participants (H. S. Bracha, D. J. Seitz, J. Otemaa, & S. D. Click, 1987). These latter authors found a complex interaction between hemispheric dominance, preferred turning side, and sex. C. Mohr et al. (2003) argued that the differentiation of the population in hemisphere-dominant groups by a compound measure of hand-foot-eye preference might have masked their recent finding. Thus, this commentary presents a reanalysis of the original data set (H. S. Bracha et al., 1987). Replicating recent observation, right-handers preferred left-sided turns; and non-righthanders, right-sided turns. This replication strengthens the proposition that handedness and turning behavior might depend on interhemispheric dopamine asymmetries. Copyright 2004 APA.

  10. Revealing turning points in ecosystem functioning over the Northern Eurasian agricultural frontier.

    PubMed

    Horion, Stéphanie; Prishchepov, Alexander V; Verbesselt, Jan; de Beurs, Kirsten; Tagesson, Torbern; Fensholt, Rasmus

    2016-08-01

    The collapse of the Soviet Union in 1991 has been a turning point in the World history that left a unique footprint on the Northern Eurasian ecosystems. Conducting large scale mapping of environmental change and separating between naturogenic and anthropogenic drivers is a difficult endeavor in such highly complex systems. In this research a piece-wise linear regression method was used for breakpoint detection in Rain-Use Efficiency (RUE) time series and a classification of ecosystem response types was produced. Supported by earth observation data, field data, and expert knowledge, this study provides empirical evidence regarding the occurrence of drastic changes in RUE (assessment of the timing, the direction and the significance of these changes) in Northern Eurasian ecosystems between 1982 and 2011. About 36% of the study area (3.4 million km(2) ) showed significant (P < 0.05) trends and/or turning points in RUE during the observation period. A large proportion of detected turning points in RUE occurred around the fall of the Soviet Union in 1991 and in the following years which were attributed to widespread agricultural land abandonment. Our study also showed that recurrent droughts deeply affected vegetation productivity throughout the observation period, with a general worsening of the drought conditions in recent years. Moreover, recent human-induced turning points in ecosystem functioning were detected and attributed to ongoing recultivation and change in irrigation practices in the Volgograd region, and to increased salinization and increased grazing intensity around Lake Balkhash. The ecosystem-state assessment method introduced here proved to be a valuable support that highlighted hotspots of potentially altered ecosystems and allowed for disentangling human from climatic disturbances. © 2016 John Wiley & Sons Ltd.

  11. Turn Basin Construction

    NASA Image and Video Library

    2017-06-14

    Modifications are underway at the Launch Complex 39 turn basin wharf at NASA's Kennedy Space Center in Florida to prepare for the arrival of the agency's massive Space Launch System (SLS) core stage aboard the barge Pegasus. Tammy Kelly, in the center, site manager, with Southeast Cherokee Construction Inc. talks with construction workers. A crane will be used to lift up precast concrete poles and position them to be driven to a depth of about 70 feet into the bedrock below the water around the turn basin. The upgrades are necessary to accommodate the increased weight of the core stage along with ground support and transportation equipment aboard the modified barge Pegasus. The Ground Systems Development and Operations Program is overseeing the upgrades to the turn basin wharf.

  12. An Active Insect Kinin Analog with 4-Aminopyroglutamate, A Novel cis-Peptide Bond, Type VI beta-Turn Motif

    DTIC Science & Technology

    2004-01-01

    2004 Wiley Periodicals, Inc.* Biopolymers 75: 412–419, 2004 Keywords: 4-aminopyroglutamic acid ; cis-peptide bond; -turn mimetic; constrained insect...biological evaluation of an insect kinin analog containing a novel, (2S,4S)-4-aminopyroglutamic acid (APy) com- ponent (Figure 1) that theoretical and...cricket diuretic bioassay system. FIGURE 1 A comparison of the structures of the tetrazole ([CN4], left) and 4-aminopyroglu- tamic acid (APy; right

  13. Hummingbirds control turning velocity using body orientation and turning radius using asymmetrical wingbeat kinematics

    PubMed Central

    Read, Tyson J. G.; Segre, Paolo S.; Middleton, Kevin M.; Altshuler, Douglas L.

    2016-01-01

    Turning in flight requires reorientation of force, which birds, bats and insects accomplish either by shifting body position and total force in concert or by using left–right asymmetries in wingbeat kinematics. Although both mechanisms have been observed in multiple species, it is currently unknown how each is used to control changes in trajectory. We addressed this problem by measuring body and wingbeat kinematics as hummingbirds tracked a revolving feeder, and estimating aerodynamic forces using a quasi-steady model. During arcing turns, hummingbirds symmetrically banked the stroke plane of both wings, and the body, into turns, supporting a body-dependent mechanism. However, several wingbeat asymmetries were present during turning, including a higher and flatter outer wingtip path and a lower more deviated inner wingtip path. A quasi-steady analysis of arcing turns performed with different trajectories revealed that changes in radius were associated with asymmetrical kinematics and forces, and changes in velocity were associated with symmetrical kinematics and forces. Collectively, our results indicate that both body-dependent and -independent force orientation mechanisms are available to hummingbirds, and that these kinematic strategies are used to meet the separate aerodynamic challenges posed by changes in velocity and turning radius. PMID:27030042

  14. Expanded turn conformations: characterization and sequence-structure correspondence in alpha-turns with implications in helix folding.

    PubMed

    Dasgupta, Bhaskar; Pal, Lipika; Basu, Gautam; Chakrabarti, Pinak

    2004-05-01

    Like the beta-turns, which are characterized by a limiting distance between residues two positions apart (i, i+3), a distance criterion (involving residues at positions i and i+4) is used here to identify alpha-turns from a database of known protein structures. At least 15 classes of alpha-turns have been enumerated based on the location in the phi,psi space of the three central residues (i+1 to i+3)-one of the major being the class AAA, where the residues occupy the conventional helical backbone torsion angles. However, moving towards the C-terminal end of the turn, there is a shift in the phi,psi angles towards more negative phi, such that the electrostatic repulsion between two consecutive carbonyl oxygen atoms is reduced. Except for the last position (i+4), there is not much similarity in residue composition at different positions of hydrogen and non-hydrogen bonded AAA turns. The presence or absence of Pro at i+1 position of alpha- and beta-turns has a bearing on whether the turn is hydrogen-bonded or without a hydrogen bond. In the tertiary structure, alpha-turns are more likely to be found in beta-hairpin loops. The residue composition at the beginning of the hydrogen bonded AAA alpha-turn has similarity with type I beta-turn and N-terminal positions of helices, but the last position matches with the C-terminal capping position of helices, suggesting that the existence of a "helix cap signal" at i+4 position prevents alpha-turns from growing into helices. Our results also provide new insights into alpha-helix nucleation and folding. Copyright 2004 Wiley-Liss, Inc.

  15. Left endocarditis, changes in the new millennium.

    PubMed

    Noureddine-López, Mariam; de la Torre-Lima, Javier; Ruiz-Morales, Josefa; Gálvez-Acebal, Juan; Hidalgo-Tenorio, Carmen; de Alarcón González, César Arístides

    2018-05-25

    a description of infective left endocarditis at the turn of the millennium. A multicentre prospective study into the left endocarditis using data collected from the Andalusian cohort for the study of cardiovascular infections during 1984-2014. Of the 1,604 endocarditis cases collected, 382 belonged to G1 (group-1, period 1983-1999) and 1,222 to G2 (group-2, 2000-2014). Patients in the new millennium have a significantly higher mean age, have more comorbidity and concomitant diseases, and nosocomial and health-related endocarditis are more frequent, as well as complications. An increase in methicillin-resistant Staphylococcus aureus, Enterococcus sp., Gram-negative bacilli and Streptococcus bovis was noted. Regarding treatment, there is an increase in the use of cephalosporins and a decrease in penicillins; there is more surgery when admitted to hospital and less delay. Mortality stands at around 30% in both millennia. In the multivariate analysis, mortality was associated with: previous millennium (G1), age, Charlson index, renal failure and septic shock, and aetiologically with Staphylococcus aureus. Mortality remains stable, despite diagnostic and therapeutic improvements, because patients are older, have greater comorbidity, a closer relationship with the health care system (nosocomial) and microorganisms are more aggressive. Copyright © 2018 Elsevier España, S.L.U. All rights reserved.

  16. Children coordinate in a recurrent social dilemma by taking turns and along dominance asymmetries.

    PubMed

    Grueneisen, Sebastian; Tomasello, Michael

    2017-02-01

    Humans constantly have to coordinate their decisions with others even when their interests are conflicting (e.g., when 2 drivers have to decide who yields at an intersection). So far, however, little is known about the development of these abilities. Here, we present dyads of 5-year-olds (N = 40) with a repeated chicken game using a novel methodology: Two children each steered an automated toy train carrying a reward. The trains simultaneously moved toward each other so that in order to avoid a crash-which left both children empty-handed-1 train had to swerve. By swerving, however, the trains lost a portion of the rewards so that it was in each child's interest to go straight. Children coordinated their decisions successfully over multiple rounds, and they mostly did so by taking turns at swerving. In dyads in which turn-taking was rare, dominant children obtained significantly higher payoffs than their partners. Moreover, the coordination process was more efficient in turn-taking dyads as indicated by a significant reduction in conflicts and verbal protest. These findings indicate that already by the late preschool years children can independently coordinate decisions with peers in recurrent conflicts of interest. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  17. Relationship Between Head-Turn Gait Speed and Lateral Balance Function in Community-Dwelling Older Adults.

    PubMed

    Singh, Harshvardhan; Sanders, Ozell; McCombe Waller, Sandy; Bair, Woei-Nan; Beamer, Brock; Creath, Robert A; Rogers, Mark W

    2017-10-01

    To determine and compare gait speed during head-forward and side-to-side head-turn walking in individuals with lower versus greater lateral balance. Cross-sectional study. University research laboratory. Older adults (N=93; 42 men, 51 women; mean age ± SD, 73 ± 6.08y) who could walk independently. (1) Balance tolerance limit (BTL), defined as the lowest perturbation intensity where a multistep balance recovery pattern was first evoked in response to randomized lateral waist-pull perturbations of standing balance to the left and right sides, at 6 different intensities (range from level 2: 4.5-cm displacement at 180cm/s 2 acceleration, to level 7: 22.5-cm displacement at 900cm/s 2 acceleration); (2) gait speed, determined using an instrumented gait mat; (3) balance, evaluated with the Activities-specific Balance Confidence Scale; and (4) mobility, determined with the Timed Up and Go (TUG). Individuals with low versus high BTL had a slower self-selected head-forward gait speed and head-turn gait speed (P=.002 and P<.001, respectively); the magnitude of difference was greater in head-turn gait speed than head-forward gait speed (Cohen's d=1.0 vs 0.6). Head-turn gait speed best predicted BTL. BTL was moderately and positively related (P=.003) to the ABC Scale and negatively related (P=.017) to TUG. Head-turn gait speed is affected to a greater extent than head-forward gait speed in older individuals with poorer lateral balance and at greater risk of falls. Moreover, head-turn gait speed can be used to assess the interactions of limitations in lateral balance function and gait speed in relation to fall risk in older adults. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  18. Realistic page-turning of electronic books

    NASA Astrophysics Data System (ADS)

    Fan, Chaoran; Li, Haisheng; Bai, Yannan

    2014-01-01

    The booming electronic books (e-books), as an extension to the paper book, are popular with readers. Recently, many efforts are put into the realistic page-turning simulation o f e-book to improve its reading experience. This paper presents a new 3D page-turning simulation approach, which employs piecewise time-dependent cylindrical surfaces to describe the turning page and constructs smooth transition method between time-dependent cylinders. The page-turning animation is produced by sequentially mapping the turning page into the cylinders with different radii and positions. Compared to the previous approaches, our method is able to imitate various effects efficiently and obtains more natural animation of turning page.

  19. Driving simulator study of J-Turn acceleration/deceleration lane and U-turn spacing.

    DOT National Transportation Integrated Search

    2016-11-01

    Carlos Sun : http://orcid.org/0000-0002-8857-9648 : The J-turn, also known as RCUT (Restricted Crossing U-Turn) and Superstreet, is an innovative geometric design that can improve intersection safety. Even though this design has been in use in severa...

  20. Abdominal aortic aneurysm with aorta-left renal vein fistula with left varicocele.

    PubMed

    Meyerson, S L; Haider, S A; Gupta, N; O'Dorsio, J E; McKinsey, J F; Schwartz, L B

    2000-04-01

    Abdominal aortic aneurysm with spontaneous aorto-left renal vein fistula is a rare but well-described clinical entity usually with abdominal pain, hematuria, and a nonfunctioning left kidney. This report describes a 44-year-old man with left-sided groin pain and varicocele who was treated with conservative measures only. The diagnosis was eventually made when he returned with microscopic hematuria, elevated serum creatinine level, and nonfunction of the left kidney; computed tomography scan demonstrated a 6-cm abdominal aortic aneurysm, a retroaortic left renal vein, and an enlargement of the left kidney. This patient represents the youngest to be reported with aorto-left renal vein fistula and the second case with a left-sided varicocele.

  1. Turn Basin Construction

    NASA Image and Video Library

    2017-06-30

    At NASA's Kennedy Space Center in Florida, cement is poured as part of a construction project to upgrade the turn basin wharf. The work includes driving multiple precast concrete piles to a depth of about 70 feet to accommodate arrival of the core stage for the agency's Space Launch System (SLS) rocket. When the stage for NASA's SLS departs the Michoud Assembly Facility in New Orleans, it will be shipped by the agency's modified barge to the Launch Complex 39 turn basin.

  2. Construction at Turn Basin

    NASA Image and Video Library

    2017-06-14

    Modifications are underway at the Launch Complex 39 turn basin wharf at NASA's Kennedy Space Center in Florida to prepare for the arrival of the agency's massive Space Launch System (SLS) core stage aboard the barge Pegasus. Precast concrete poles are being driven to a depth of about 70 feet into the bedrock below the water around the turn basin; later filled with concrete. The upgrades are necessary to accommodate the increased weight of the core stage along with ground support and transportation equipment aboard the modified barge Pegasus. The Ground Systems Development and Operations Program is overseeing the upgrades to the turn basin wharf.

  3. Does serotonin-modulating anticonsolidation protein (SMAP) influence the choice of turning direction in carps, Cyprinus carpio, in a T-maze?

    PubMed

    Garina, D V; Nepomnyashchikh, V A; Mekhtiev, A A

    2016-08-01

    Serotonin-modulating anticonsolidation protein (SMAP) can impair the formation of memory traces in mammals and fish. We have studied the influence of SMAP on behavioral lateralization of juvenile carps Cyprinus carpio in a T-maze without food reinforcement in three experimental groups (n = 8 each): (1) negative control (intact animals); (2) experimental group (fish injected ICV with SMAP; 2 μl, 1.2 mg ml(-1)) and (3) active control group (fish injected ICV with inactivated SMAP). The behavioral lateralization of carps was observed on the 1st, 2nd, 3rd and 6th days after the injections. In each observation session, a fish was placed five times in a start chamber of the T-maze. The direction of the turn upon leaving the start chamber, as well as the latency from the opening of start chamber flap to the fish's turn was registered. The number of right turns (of all five turns observed during the session) was a criterion of lateralization. It was found that carps have no inherent preference for turning left or right. The SMAP injection did not influence the choice of turning direction, but increases latency values insignificantly. The results are important for the correct interpretation and clarification of data reporting the role of SMAP in training and formation of spatial memory of fish in a maze.

  4. 14 CFR 417.209 - Malfunction turn analysis.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... turn behavior for each cause of a malfunction turn. For each malfunction turn envelope, the analysis... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Malfunction turn analysis. 417.209 Section..., DEPARTMENT OF TRANSPORTATION LICENSING LAUNCH SAFETY Flight Safety Analysis § 417.209 Malfunction turn...

  5. 14 CFR 417.209 - Malfunction turn analysis.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... turn behavior for each cause of a malfunction turn. For each malfunction turn envelope, the analysis... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Malfunction turn analysis. 417.209 Section..., DEPARTMENT OF TRANSPORTATION LICENSING LAUNCH SAFETY Flight Safety Analysis § 417.209 Malfunction turn...

  6. 14 CFR 417.209 - Malfunction turn analysis.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... turn behavior for each cause of a malfunction turn. For each malfunction turn envelope, the analysis... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Malfunction turn analysis. 417.209 Section..., DEPARTMENT OF TRANSPORTATION LICENSING LAUNCH SAFETY Flight Safety Analysis § 417.209 Malfunction turn...

  7. NetTurnP--neural network prediction of beta-turns by use of evolutionary information and predicted protein sequence features.

    PubMed

    Petersen, Bent; Lundegaard, Claus; Petersen, Thomas Nordahl

    2010-11-30

    β-turns are the most common type of non-repetitive structures, and constitute on average 25% of the amino acids in proteins. The formation of β-turns plays an important role in protein folding, protein stability and molecular recognition processes. In this work we present the neural network method NetTurnP, for prediction of two-class β-turns and prediction of the individual β-turn types, by use of evolutionary information and predicted protein sequence features. It has been evaluated against a commonly used dataset BT426, and achieves a Matthews correlation coefficient of 0.50, which is the highest reported performance on a two-class prediction of β-turn and not-β-turn. Furthermore NetTurnP shows improved performance on some of the specific β-turn types. In the present work, neural network methods have been trained to predict β-turn or not and individual β-turn types from the primary amino acid sequence. The individual β-turn types I, I', II, II', VIII, VIa1, VIa2, VIba and IV have been predicted based on classifications by PROMOTIF, and the two-class prediction of β-turn or not is a superset comprised of all β-turn types. The performance is evaluated using a golden set of non-homologous sequences known as BT426. Our two-class prediction method achieves a performance of: MCC=0.50, Qtotal=82.1%, sensitivity=75.6%, PPV=68.8% and AUC=0.864. We have compared our performance to eleven other prediction methods that obtain Matthews correlation coefficients in the range of 0.17-0.47. For the type specific β-turn predictions, only type I and II can be predicted with reasonable Matthews correlation coefficients, where we obtain performance values of 0.36 and 0.31, respectively. The NetTurnP method has been implemented as a webserver, which is freely available at http://www.cbs.dtu.dk/services/NetTurnP/. NetTurnP is the only available webserver that allows submission of multiple sequences.

  8. Intraoperative left subclavian artery occlusion with left hand ischaemia and steal syndrome in the left internal thoracic artery

    PubMed Central

    Jelenc, Matija; Kneževič, Ivan; Stankovič, Milenko; Geršak, Borut

    2012-01-01

    We present a case of a 62-year old man with a left main stenosis, left coronary artery dominance, normal ejection fraction and no valvular pathology, and status post right carotid artery stenting, who was scheduled for elective coronary revascularization. We performed off-pump coronary revascularization, anastomosing the left internal thoracic artery to the left anterior descending artery, and three separate saphenous vein grafts to the intermediate artery and the first and second obtuse marginals, respectively. Proximally, the right internal thoracic artery was used as the inflow for all three venous grafts due to a heavily calcified ascending aorta. During the construction of the distal anastomoses to the obtuse marginals, the arterial pressure in the left radial artery suddenly dropped. The left hand was found to be pale and pulseless. A femoral artery catheter was placed for pressure monitoring and the anastomoses were completed as planned. Intraoperative transit-time graft flow measurement showed a reversed flow in the left internal thoracic artery. Postoperatively, angiography was performed showing a subtotal stenosis of the proximal left subclavian artery. The artery was dilated and stented. The postoperative course was uneventful and the patient was discharged on the 12th postoperative day. PMID:22767542

  9. Turn Basin Construction

    NASA Image and Video Library

    2017-06-30

    Across from the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida, cement trucks stand by to support a construction project to upgrade the turn basin wharf. The work includes driving multiple precast concrete piles to a depth of about 70 feet to accommodate arrival of the core stage for the agency's Space Launch System (SLS) rocket. When the stage for NASA's SLS departs the Michoud Assembly Facility in New Orleans, it will be shipped by the agency's modified barge to the Launch Complex 39 turn basin.

  10. Turn Basin Construction

    NASA Image and Video Library

    2017-06-30

    Across from the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida, cement is poured as part of a construction project to upgrade the turn basin wharf. The work includes driving multiple precast concrete piles to a depth of about 70 feet to accommodate arrival of the core stage for the agency's Space Launch System (SLS) rocket. When the stage for NASA's SLS departs the Michoud Assembly Facility in New Orleans, it will be shipped by the agency's modified barge to the Launch Complex 39 turn basin.

  11. Beta-and gamma-turns in proteins revisited: a new set of amino acid turn-type dependent positional preferences and potentials.

    PubMed

    Guruprasad, K; Rajkumar, S

    2000-06-01

    The number of beta-turns in a representative set of 426 protein three-dimensional crystal structures selected from the recent Protein Data Bank has nearly doubled and the number of gamma-turns in a representative set of 320 proteins has increased over seven times since the previous analysis. Beta-turns (7153) and gamma-turns (911) extracted from these proteins were used to derive a revised set of type-dependent amino acid positional preferences and potentials. Compared with previous results, the preference for proline, methionine and tryptophan has increased and the preference for glutamine, valine, glutamic acid and alanine has decreased for beta-turns. Certain new amino acid preferences were observed for both turn types and individual amino acids showed turn-type dependent positional preferences. The rationale for new amino acid preferences are discussed in the light of hydrogen bonds and other interactions involving the turns. Where main-chain hydrogen bonds of the type NH(i + 3) --> CO(i) were not observed for some beta-turns, other main-chain hydrogen bonds or solvent interactions were observed that possibly stabilize such beta-turns. A number of unexpected isolated beta-turns with proline at i + 2 position were also observed. The NH(i + 2) --> CO(i) hydrogen bond was observed for almost all gamma-turns. Nearly 20% classic gamma-turns and 43% inverse gamma-turns are isolated turns.

  12. Animal left-right asymmetry.

    PubMed

    Blum, Martin; Ott, Tim

    2018-04-02

    Symmetry is appealing, be it in architecture, art or facial expression, where symmetry is a key feature to finding someone attractive or not. Yet, asymmetries are widespread in nature, not as an erroneous deviation from the norm but as a way to adapt to the prevailing environmental conditions at a time. Asymmetries in many cases are actively selected for: they might well have increased the evolutionary fitness of a species. Even many single-celled organisms are built asymmetrically, such as the pear-shaped ciliate Paramecium, which may depend on its asymmetry to navigate towards the oxygen-richer surface of turbid waters, at least based on modeling. Everybody knows the lobster with its asymmetric pair of claws, the large crusher usually on the left and the smaller cutter on the right. Snail shells coil asymmetrically, as do the organs they house. Organ asymmetries are found throughout the animal kingdom, referring to asymmetric positioning, asymmetric morphology or both, with the vertebrate heart being an example for the latter. Functional asymmetries, such as that of the human brain with its localization of the language center in one hemisphere, add to the complexity of organ asymmetries and presumably played a decisive role for sociocultural evolution. The evolutionary origin of organ asymmetries may have been a longer than body length gut, which allows efficient retrieval of nutrients, and the need to stow a long gut in the body cavity in an orderly manner that ensures optimal functioning. Vertebrate organ asymmetries (situs solitus) are quite sophisticated: in humans, the apex of the asymmetrically built heart points to the left; the lung in turn, due to space restrictions, has fewer lobes on the left than on the right side (two versus three in humans), stomach and spleen are found on the left, the liver on the right, and small and large intestine coil in a chiral manner (Figure 1A). In very rare cases (1:10,000), the organ situs is inverted (situs inversus

  13. KENNEDY SPACE CENTER, FLA. - In a brief ceremony in the Space Station Processing Facility, Chuck Hardison (left), Boeing senior truss manager, turns over the “key” for the starboard truss segment S3/S4 to Scott Gahring, ISS Vehicle Office manager (acting), Johnson Space Center. The trusses are scheduled to be delivered to the International Space Station on mission STS-117.

    NASA Image and Video Library

    2004-02-12

    KENNEDY SPACE CENTER, FLA. - In a brief ceremony in the Space Station Processing Facility, Chuck Hardison (left), Boeing senior truss manager, turns over the “key” for the starboard truss segment S3/S4 to Scott Gahring, ISS Vehicle Office manager (acting), Johnson Space Center. The trusses are scheduled to be delivered to the International Space Station on mission STS-117.

  14. What Bed Size Does a Patient Need? The Relationship Between Body Mass Index and Space Required to Turn in Bed.

    PubMed

    Wiggermann, Neal; Smith, Kathryn; Kumpar, Dee

    A bed that is too small to allow patients to turn from supine to side lying increases the difficulty of mobilizing patients, which can increase risk of musculoskeletal injury to caregivers, increase risk of pressure injuries to patients, and reduce patient comfort. Currently, no guidance is available for what patient sizes are accommodated by the standard 91cm (36 in.)-wide hospital bed, and no studies have evaluated the relationship between anthropometric attributes and space required to turn in bed. The purpose of this research was to determine how much space individuals occupy when turning from supine to side lying as predicted by their anthropometry (i.e., body dimensions) to establish guidance on selecting the appropriate bed size. Forty-seven adult participants (24 female) with body mass index (BMI) from 20 to 76 kg/m participated in a laboratory study. Body dimensions were measured, and the envelope of space required to turn was determined using motion capture. Linear regressions estimated the relationship between anthropometric attributes and space occupied when turning. BMI was strongly correlated (R = .88) with the space required to turn. Based on the linear regressions, individuals with BMI up to 35 kg/m could turn left and right within 91 cm and individuals with BMI up to 45 kg/m could turn one direction within 91 cm. BMI is a good predictor of the space required to turn from supine to lateral. Nurses should consider placing patients that are unable to laterally reposition themselves on a wider bed when BMI is greater than 35 kg/m and should consider placing all patients greater than 45 kg/m on a wider bed regardless of mobility. Hospital administrators can use historical demographic information about the BMI of their patient populations to plan facility-level equipment procurement for equipment that accommodates their patients.

  15. STS-92 Mission Specialist McArthur is ready to take his turn driving the M-113

    NASA Technical Reports Server (NTRS)

    2000-01-01

    STS-92 Mission Specialist Bill McArthur gets ready to take his turn at driving the M-113, part of emergency egress training during Terminal Countdown Demonstration Test (TCDT) activities. Behind him (left) is Mission Specialist Jeff Wisoff, waiting his turn to drive along with other unidentified crew members. The tracked vehicle could be used by the crew in the event of an emergency at the pad during which the crew must make a quick exit from the area. The TCDT also provides simulated countdown exercises and opportunities to inspect the mission payloads in the orbiter's payload bay. STS-92 is scheduled to launch Oct. 5 at 9:30 p.m. EDT on the fifth flight to the International Space Station. It will carry two elements of the Space Station, the Integrated Truss Structure Z1 and the third Pressurized Mating Adapter. The mission is also the 100th flight in the Shuttle program.

  16. Why PeV scale left-right symmetry is a good thing

    NASA Astrophysics Data System (ADS)

    Yajnik, Urjit A.

    2017-10-01

    Left-right symmetric gauge theory presents a minimal paradigm to accommodate massive neutrinos with all the known conserved symmetries duly gauged. The work presented here is based on the argument that the see-saw mechanism does not force the new right-handed symmetry scale to be very high, and as such some of the species from the spectrum of the new gauge and Higgs bosons can have masses within a few orders of magnitude of the TeV scale. The scale of the left-right parity breaking in turn can be sequestered from the Planck scale by supersymmetry. We have studied several formulations of such just beyond Standard Model (JBSM) theories for their consistency with cosmology. Specifically, the need to eliminate phenomenologically undesirable domain walls gives many useful clues. The possibility that the exact left-right symmetry breaks in conjunction with supersymmetry has been explored in the context of gauge mediation, placing restrictions on the available parameter space. Finally, we have also studied a left-right symmetric model in the context of metastable supersymmetric vacua and obtained constraints on the mass scale of right-handed symmetry. In all the cases studied, the mass scale of the right-handed neutrino M_R remains bounded from above, and in some of the cases the scale 10^9 GeV favourable for supersymmetric thermal leptogenesis is disallowed. On the other hand, PeV scale remains a viable option, and the results warrant a more detailed study of such models for their observability in collider and astroparticle experiments.

  17. Aptamer-mediated 'turn-off/turn-on' nanozyme activity of gold nanoparticles for kanamycin detection.

    PubMed

    Sharma, Tarun Kumar; Ramanathan, Rajesh; Weerathunge, Pabudi; Mohammadtaheri, Mahsa; Daima, Hemant Kumar; Shukla, Ravi; Bansal, Vipul

    2014-12-28

    A new ultrafast and highly sensitive 'turn-off/turn-on' biosensing approach that combines the intrinsic peroxidase-like activity of gold nanoparticles (GNPs) with the high affinity and specificity of a ssDNA aptamer is presented for the efficient detection of a model small molecule kanamycin.

  18. Conformational interconversions in peptide beta-turns: analysis of turns in proteins and computational estimates of barriers.

    PubMed

    Gunasekaran, K; Gomathi, L; Ramakrishnan, C; Chandrasekhar, J; Balaram, P

    1998-12-18

    The two most important beta-turn features in peptides and proteins are the type I and type II turns, which differ mainly in the orientation of the central peptide unit. Facile conformational interconversion is possible, in principle, by a flip of the central peptide unit. Homologous crystal structures afford an opportunity to structurally characterize both possible conformational states, thus allowing identification of sites that are potentially stereochemically mobile. A representative data set of 250 high-resolution (turns that are assigned different conformational types (type I/type II) in related structures. A total of 55 examples of beta-turns were identified as possible candidates for a stereochemically mobile site. Of the 55 examples, 45 could be classified as a potential site for interconversion between type I and type II beta-turns, while ten correspond to flips from type I' to type II' structures. As a further check, the temperature factors of the central peptide unit carbonyl oxygen atom of the 55 examples were examined. The analysis reveals that the turn assignments are indeed reliable. Examination of the secondary structures at the flanking positions of the flippable beta-turns reveals that seven examples occur in the loop region of beta-hairpins, indicating that the formation of ordered secondary structures on either side of the beta-turn does not preclude local conformational variations. In these beta-turns, Pro (11 examples), Lys (nine examples) and Ser (seven examples) were most often found at the i+1 position. Glycine was found to occur overwhelmingly at position i+2 (28 examples), while Ser (seven examples) and Asn (six examples) were amongst the most frequent residues. Activation energy barriers for the interconversion between type I and type II beta-turns were computed

  19. 32 CFR 636.23 - Turning movements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Turning movements. 636.23 Section 636.23 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) LAW ENFORCEMENT AND CRIMINAL... movements. (a) U-turns are prohibited on all streets in the cantonment area. (b) Right-turns will be made...

  20. Turn stability in beta-hairpin peptides: Investigation of peptides containing 3:5 type I G1 bulge turns.

    PubMed

    Blandl, Tamas; Cochran, Andrea G; Skelton, Nicholas J

    2003-02-01

    The turn-forming ability of a series of three-residue sequences was investigated by substituting them into a well-characterized beta-hairpin peptide. The starting scaffold, bhpW, is a disulfide-cyclized 10-residue peptide that folds into a stable beta-hairpin with two antiparallel strands connected by a two-residue reverse turn. Substitution of the central two residues with the three-residue test sequences leads to less stable hairpins, as judged by thiol-disulfide equilibrium measurements. However, analysis of NMR parameters indicated that each molecule retains a significant folded population, and that the type of turn adopted by the three-residue sequence is the same in all cases. The solution structure of a selected peptide with a PDG turn contained an antiparallel beta-hairpin with a 3:5 type I + G1 bulge turn. Analysis of the energetic contributions of individual turn residues in the series of peptides indicates that substitution effects have significant context dependence, limiting the predictive power of individual amino acid propensities for turn formation. The most stable and least stable sequences were also substituted into a more stable disulfide-cyclized scaffold and a linear beta-hairpin scaffold. The relative stabilities remained the same, suggesting that experimental measurements in the bhpW context are a useful way to evaluate turn stability for use in protein design projects. Moreover, these scaffolds are capable of displaying a diverse set of turns, which can be exploited for the mimicry of protein loops or for generating libraries of reverse turns.

  1. Turning collectors for solar radiation

    DOEpatents

    Barak, Amitzur Z.

    1976-01-01

    A device is provided for turning a solar collector about the polar axis so that the collector is directed toward the sun as the sun tracks the sky each day. It includes two heat-expansive elements and a shadow plate. In the morning a first expansive element is heated, expands to turn the collector to face the sun, while the second expansive element is shaded by the plate. In the afternoon the second element is heated, expands to turn the collector to face the sun, while the first is shaded by the plate.

  2. Super Gate Turn-Off Thyristor

    DTIC Science & Technology

    2006-08-01

    semiconductor (nMOS) and turned it off through a positive metal oxide semiconductor (pMOS). For turn-on, although 1 V worked, a HP6227B power supply at 2...E3614A power supply at –8 V provided IG during the rise time, and thus need enough capacitance working to a frequency around 3/trise time...load’s screw terminal posts would have reduced the ESL and ESR. The SGTO turned off 5.8 A from the power supply at 20 V and was usually fan cooled

  3. When Is It My Turn To Speak?

    ERIC Educational Resources Information Center

    Orestrom, Bengt

    A study analyzed four dyadic conversations for evidence of the signals operating in the turn-taking process and facilitating the smooth exchange of turns. It found over 20 syntactic, prosodic, and semantic features occurring frequently with turn-taking. The five most significant factors correlating with turn-taking were a prosodically completed…

  4. NetTurnP – Neural Network Prediction of Beta-turns by Use of Evolutionary Information and Predicted Protein Sequence Features

    PubMed Central

    Petersen, Bent; Lundegaard, Claus; Petersen, Thomas Nordahl

    2010-01-01

    β-turns are the most common type of non-repetitive structures, and constitute on average 25% of the amino acids in proteins. The formation of β-turns plays an important role in protein folding, protein stability and molecular recognition processes. In this work we present the neural network method NetTurnP, for prediction of two-class β-turns and prediction of the individual β-turn types, by use of evolutionary information and predicted protein sequence features. It has been evaluated against a commonly used dataset BT426, and achieves a Matthews correlation coefficient of 0.50, which is the highest reported performance on a two-class prediction of β-turn and not-β-turn. Furthermore NetTurnP shows improved performance on some of the specific β-turn types. In the present work, neural network methods have been trained to predict β-turn or not and individual β-turn types from the primary amino acid sequence. The individual β-turn types I, I', II, II', VIII, VIa1, VIa2, VIba and IV have been predicted based on classifications by PROMOTIF, and the two-class prediction of β-turn or not is a superset comprised of all β-turn types. The performance is evaluated using a golden set of non-homologous sequences known as BT426. Our two-class prediction method achieves a performance of: MCC  = 0.50, Qtotal = 82.1%, sensitivity  = 75.6%, PPV  = 68.8% and AUC  = 0.864. We have compared our performance to eleven other prediction methods that obtain Matthews correlation coefficients in the range of 0.17 – 0.47. For the type specific β-turn predictions, only type I and II can be predicted with reasonable Matthews correlation coefficients, where we obtain performance values of 0.36 and 0.31, respectively. Conclusion The NetTurnP method has been implemented as a webserver, which is freely available at http://www.cbs.dtu.dk/services/NetTurnP/. NetTurnP is the only available webserver that allows submission of multiple sequences. PMID:21152409

  5. Experimental Study of Turning Temperature and Turning Vibration for the Tool of Different Wear State

    NASA Astrophysics Data System (ADS)

    Li, Shuncai; Yu, Qiu; Yuan, Guanlei; Liang, Li

    2018-03-01

    By a vibration test device and Vib’SYS analysis system, a three-dimensional piezoelectric acceleration sensor and an infrared thermometer and its collection system, the turning experiments under different spindle speeds were carried out on three cutting tools with different wear states, and the change law of cutting temperature at the tool tip and change law of three-dimensional vibration with turning time were obtained. The results indicate that: (1) The temperature of the initial wear tool and the middle wear tool under a small turning parameter increased slowly with turning time; while under a greater turning parameter, the temperature of the middle wear tool varies significantly with time; (2) The temperature of the severe wear tool increased sharply at the later feeding stage; (3) The change laws of the tools vibration acceleration maximum with the spindle speeds are similar for the initial wear tool and the middle wear tool, which shows a trend of increasing at first and then decreasing; (4) the average value of vibration acceleration self-power spectrum of severe wear tool constantly increase with the spindle speed; (5) the maximum impact is along the radial direction for the tools of different wear state.

  6. Hydrodynamics of Turning Flocks.

    PubMed

    Yang, Xingbo; Marchetti, M Cristina

    2015-12-18

    We present a hydrodynamic model of flocking that generalizes the familiar Toner-Tu equations to incorporate turning inertia of well-polarized flocks. The continuum equations controlled by only two dimensionless parameters, orientational inertia and alignment strength, are derived by coarse-graining the inertial spin model recently proposed by Cavagna et al. The interplay between orientational inertia and bend elasticity of the flock yields anisotropic spin waves that mediate the propagation of turning information throughout the flock. The coupling between spin-current density to the local vorticity field through a nonlinear friction gives rise to a hydrodynamic mode with angular-dependent propagation speed at long wavelengths. This mode becomes unstable as a result of the growth of bend and splay deformations augmented by the spin wave, signaling the transition to complex spatiotemporal patterns of continuously turning and swirling flocks.

  7. Predicting turns in proteins with a unified model.

    PubMed

    Song, Qi; Li, Tonghua; Cong, Peisheng; Sun, Jiangming; Li, Dapeng; Tang, Shengnan

    2012-01-01

    Turns are a critical element of the structure of a protein; turns play a crucial role in loops, folds, and interactions. Current prediction methods are well developed for the prediction of individual turn types, including α-turn, β-turn, and γ-turn, etc. However, for further protein structure and function prediction it is necessary to develop a uniform model that can accurately predict all types of turns simultaneously. In this study, we present a novel approach, TurnP, which offers the ability to investigate all the turns in a protein based on a unified model. The main characteristics of TurnP are: (i) using newly exploited features of structural evolution information (secondary structure and shape string of protein) based on structure homologies, (ii) considering all types of turns in a unified model, and (iii) practical capability of accurate prediction of all turns simultaneously for a query. TurnP utilizes predicted secondary structures and predicted shape strings, both of which have greater accuracy, based on innovative technologies which were both developed by our group. Then, sequence and structural evolution features, which are profile of sequence, profile of secondary structures and profile of shape strings are generated by sequence and structure alignment. When TurnP was validated on a non-redundant dataset (4,107 entries) by five-fold cross-validation, we achieved an accuracy of 88.8% and a sensitivity of 71.8%, which exceeded the most state-of-the-art predictors of certain type of turn. Newly determined sequences, the EVA and CASP9 datasets were used as independent tests and the results we achieved were outstanding for turn predictions and confirmed the good performance of TurnP for practical applications.

  8. Predicting Turns in Proteins with a Unified Model

    PubMed Central

    Song, Qi; Li, Tonghua; Cong, Peisheng; Sun, Jiangming; Li, Dapeng; Tang, Shengnan

    2012-01-01

    Motivation Turns are a critical element of the structure of a protein; turns play a crucial role in loops, folds, and interactions. Current prediction methods are well developed for the prediction of individual turn types, including α-turn, β-turn, and γ-turn, etc. However, for further protein structure and function prediction it is necessary to develop a uniform model that can accurately predict all types of turns simultaneously. Results In this study, we present a novel approach, TurnP, which offers the ability to investigate all the turns in a protein based on a unified model. The main characteristics of TurnP are: (i) using newly exploited features of structural evolution information (secondary structure and shape string of protein) based on structure homologies, (ii) considering all types of turns in a unified model, and (iii) practical capability of accurate prediction of all turns simultaneously for a query. TurnP utilizes predicted secondary structures and predicted shape strings, both of which have greater accuracy, based on innovative technologies which were both developed by our group. Then, sequence and structural evolution features, which are profile of sequence, profile of secondary structures and profile of shape strings are generated by sequence and structure alignment. When TurnP was validated on a non-redundant dataset (4,107 entries) by five-fold cross-validation, we achieved an accuracy of 88.8% and a sensitivity of 71.8%, which exceeded the most state-of-the-art predictors of certain type of turn. Newly determined sequences, the EVA and CASP9 datasets were used as independent tests and the results we achieved were outstanding for turn predictions and confirmed the good performance of TurnP for practical applications. PMID:23144872

  9. Epinephrine and left atrial and left ventricular diastolic function decrease in normal subjects.

    PubMed

    Fuenmayor, Abdel J; Solórzano, Moisés I; Gómez, Luisangelly

    2016-10-01

    We assessed the effect of epinephrine over left atrial and left ventricular diastolic function in subjects without structural heart disease. Twenty-seven, 34.6±17.2year-old patients without structural heart disease were included. Intravenous epinephrine (50 to 100ng/kg/min) was infused. Left atrial and ventricular functions were evaluated by means of echocardiography before and during the epinephrine infusion. No complications were observed. Significant increases in heart rate and systolic blood pressure were recorded. Both left atrial (minimal and maximal) volumes increased but increase in the minimal volume was more pronounced, and the ejection fraction diminished. Left atrial expansion index decreased and the fraction of left ventricular inflow volume resulting from atrial contraction increased. Two patients displayed abnormal left ventricular diastolic function. During epinephrine infusion, E/A and e' decreased, and isovolumetric relaxation time increased. In this group of young adults without structural heart disease, epinephrine infusion was safe, did not produce any complications, and induced a small but significant decrease in left atrial function and left ventricular diastolic function. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  10. Upper-surface-blowing flow-turning performance

    NASA Technical Reports Server (NTRS)

    Sleeman, W. C., Jr.; Phelps, A. E., III

    1976-01-01

    Jet exhaust flow-turning characteristics were determined for systematic variations in upper-surface blowing exhaust nozzles and trailing-edge flap configuration variables from experimental wind-off (static) flow studies. For conditions with parallel flow exhausting from the nozzle, jet height (as indicated by nozzle exit height) and flap radius were found to be the most important parameters relating to flow turning. Nonparallel flow from the nozzle, as obtained from an internal roof angle and/or side spread angle, had a large favorable effect on flow turning. Comparisons made between static turning results and wind tunnel aerodynamic studies of identical configurations indicated that static flow-turning results can be indicative of wind-on powered lift performance for both good and poor nozzle-flap combinations but, for marginal designs, can lead to overly optimistic assessment of powered lift potential.

  11. Node and midline defects are associated with left-right development in Delta1 mutant embryos.

    PubMed

    Przemeck, Gerhard K H; Heinzmann, Ulrich; Beckers, Johannes; Hrabé de Angelis, Martin

    2003-01-01

    Axes formation is a fundamental process of early embryonic development. In addition to the anteroposterior and dorsoventral axes, the determination of the left-right axis is crucial for the proper morphogenesis of internal organs and is evolutionarily conserved in vertebrates. Genes known to be required for the normal establishment and/or maintenance of left-right asymmetry in vertebrates include, for example, components of the TGF-beta family of intercellular signalling molecules and genes required for node and midline function. We report that Notch signalling, which previously had not been implicated in this morphogenetic process, is required for normal left-right determination in mice. We show, that the loss-of-function of the delta 1 (Dll1) gene causes a situs ambiguous phenotype, including randomisation of the direction of heart looping and embryonic turning. The most probable cause for this left-right defect in Dll1 mutant embryos is a failure in the development of proper midline structures. These originate from the node, which is disrupted and deformed in Dll1 mutant embryos. Based on expression analysis in wild-type and mutant embryos, we suggest a model, in which Notch signalling is required for the proper differentiation of node cells and node morphology.

  12. Left arm underdevelopment secondary to an isolated left subclavian artery in tetralogy of Fallot.

    PubMed

    Carnero Alcázar, Manuel; Marianeschi, Stefano; Ruiz Alonso, Enrique; García Torres, Enrique; Comas, Juan V

    2010-02-01

    The anomalous origin of the left subclavian artery is known to be associated with right aortic arch and tetralogy of Fallot. In our case, the left subclavian artery arose from the left pulmonary artery. Therefore, the left arm was perfused by poorly oxygenated blood from pulmonary arteries and some retrograde vertebral artery flow. Thus, the left arm was cyanotic and less developed than the right one. The patient underwent surgical repair with complete correction of tetralogy of Fallot and reimplantation of the left subclavian artery to the left carotid artery. 2010 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  13. 33 CFR 401.48 - Turning basins.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    .... 1—Opposite Brossard. (b) Turning Basin No. 2—Between Lock 7 and the Guard Gate Cut for vessels up to... vessels up to 107 m in overall length. (b) Turning Basin No. 2—Between Lock 7 and the Guard Gate Cut for...). (d) Turning Basin No. 4—North of Lock No. 8 for vessels up to 170 m in overall length. (e) For...

  14. 33 CFR 401.48 - Turning basins.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    .... 1—Opposite Brossard. (b) Turning Basin No. 2—Between Lock 7 and the Guard Gate Cut for vessels up to... vessels up to 107 m in overall length. (b) Turning Basin No. 2—Between Lock 7 and the Guard Gate Cut for...). (d) Turning Basin No. 4—North of Lock No. 8 for vessels up to 170 m in overall length. (e) For...

  15. Why Does Hair Turn Gray?

    MedlinePlus

    ... Videos for Educators Search English Español Why Does Hair Turn Gray? KidsHealth / For Kids / Why Does Hair Turn Gray? Print en español ¿Por qué se ... ever watched someone try to cover up gray hair by dyeing it? Or maybe you wonder why ...

  16. [Left-handedness and health].

    PubMed

    Milenković, Sanja; Belojević, Goran; Kocijancić, Radojka

    2010-01-01

    Hand dominance is defined as a proneness to use one hand rather than another in performing the majority of activities and this is the most obvious example of cerebral lateralization and an exclusive human characteristic. Left-handed people comprise 6-14% of the total population, while in Serbia, this percentage is 5-10%, moving from undeveloped to developed environments, where a socio-cultural pressure is less present. There is no agreement between investigators who in fact may be considered a left-handed person, about the percentage of left-handers in the population and about the etiology of left-handedness. In the scientific literature left-handedness has been related to health disorders (spine deformities, immunological disorders, migraine, neurosis, depressive psychosis, schizophrenia, insomnia, homosexuality, diabetes mellitus, arterial hypertension, sleep apnea, enuresis nocturna and Down Syndrome), developmental disorders (autism, dislexia and sttutering) and traumatism. The most reliable scientific evidences have been published about the relationship between left-handedness and spinal deformities in school children in puberty and with traumatism in general population. The controversy of other results in up-to-now investigations of health aspects of left-handedness may partly be explained by a scientific disagreement whether writing with the left hand is a sufficient criterium for left-handedness, or is it necessary to investigate other parameters for laterality assessment. Explanation of health aspects of left-handedness is dominantly based on Geschwind-Galaburda model about "anomalous" cerebral domination, as a consequence of hormonal disbalance.

  17. Transient left septal fascicular block and left anterior fascicular block as a consequence of proximal subocclusion of the left anterior descending coronary artery.

    PubMed

    Pérez-Riera, Andrés Ricardo; Barbosa-Barros, Raimundo; Daminello-Raimundo, Rodrigo; de Abreu, Luiz Carlos; Nikus, Kjell

    2018-04-19

    The association of left anterior fascicular block (LAFB) with left septal fascicular block (LSFB) characterizes a left bifascicular block subtype rarely described in the literature, probably due to the fact that most researchers are not aware of the existence of the left septal fascicle. We describe a case with this transient intraventricular dromotropic disturbance due to left anterior descending coronary artery subocclusion. © 2018 Wiley Periodicals, Inc.

  18. Prediction of beta-turns with learning machines.

    PubMed

    Cai, Yu-Dong; Liu, Xiao-Jun; Li, Yi-Xue; Xu, Xue-biao; Chou, Kuo-Chen

    2003-05-01

    The support vector machine approach was introduced to predict the beta-turns in proteins. The overall self-consistency rate by the re-substitution test for the training or learning dataset reached 100%. Both the training dataset and independent testing dataset were taken from Chou [J. Pept. Res. 49 (1997) 120]. The success prediction rates by the jackknife test for the beta-turn subset of 455 tetrapeptides and non-beta-turn subset of 3807 tetrapeptides in the training dataset were 58.1 and 98.4%, respectively. The success rates with the independent dataset test for the beta-turn subset of 110 tetrapeptides and non-beta-turn subset of 30,231 tetrapeptides were 69.1 and 97.3%, respectively. The results obtained from this study support the conclusion that the residue-coupled effect along a tetrapeptide is important for the formation of a beta-turn.

  19. Left atriotomy versus right atriotomy trans-septal approach for left atrial myxoma.

    PubMed

    Hatemi, A C; Gürsoy, M; Tongut, A; Kiliçkesmez, K; Karaoğlu, K; Küçükoğlu, S; Kansiz, E

    2010-01-01

    The biatrial approach has been the classic means of access for left atrial myxoma resection. Increased surgical experience led cardiac surgeons to favour the uniatrial approach to reduce incisions and achieve adequate exposure. In this study, two unilateral surgical approaches were compared in 18 consecutive left atrial myxoma cases. Patients were divided into two groups according to the surgical approach: left atriotomy (group 1, n = 9) and right atriotomy trans-septal approach (group 2, n = 9). Comparison criteria included pre- and post-operative functional capacity, cardiac rhythm, left ventricular ejection fraction, pulmonary artery pressure, left atrial dimensions, cardiopulmonary bypass time, aortic cross-clamp time, drainage over 48 h post-operatively, units of blood transfused, extubation time and length of stay in the intensive care unit and hospital. No significant between-group difference was observed in any criteria except aortic cross-clamp time, which was significantly longer in group 2 than in group 1. No recurrence of myxoma occurred in either group for the 15 patients followed up. Right atrial trans-septal incision appears to be as safe and effective as the left atriotomy approach for left atrial myxoma resection.

  20. Hypoplastic left heart syndrome

    MedlinePlus

    HLHS; Congenital heart - hypoplastic left heart; Cyanotic heart disease - hypoplastic left heart ... Hypoplastic left heart is a rare type of congenital heart disease. It is more common in males than in females. As ...

  1. Taking Turns

    ERIC Educational Resources Information Center

    Hopkins, Brian

    2010-01-01

    Two people take turns selecting from an even number of items. Their relative preferences over the items can be described as a permutation, then tools from algebraic combinatorics can be used to answer various questions. We describe each person's optimal selection strategies including how each could make use of knowing the other's preferences. We…

  2. Seesaw at Lhc Through Left-Right Symmetry

    NASA Astrophysics Data System (ADS)

    Senjanović, Goran

    I argue that LHC may shed light on the nature of neutrino mass through the probe of the seesaw mechanism. The smoking gun signature is lepton number violation through the production of same sign lepton pairs, a collider analogy of the neutrinoless double beta decay. I discuss this in the context of left-right symmetric theories, which led originally to neutrino mass and the seesaw mechanism. A WR gauge boson with a mass in a few TeV region could easily dominate neutrinoless double beta decay, and its discovery at LHC would have spectacular signatures of parity restoration and lepton number violation. Moreover, LHC can measure the masses of the right-handed neutrinos and the right-handed leptonic mixing matrix, which could in turn be used to predict the rates for neutrinoless double decay and lepton flavor violating violating processes. The LR scale at the LHC energies offers great hope of observing these low energy processes in the present and upcoming experiments.

  3. Extension of the classical classification of β-turns

    PubMed Central

    de Brevern, Alexandre G.

    2016-01-01

    The functional properties of a protein primarily depend on its three-dimensional (3D) structure. These properties have classically been assigned, visualized and analysed on the basis of protein secondary structures. The β-turn is the third most important secondary structure after helices and β-strands. β-turns have been classified according to the values of the dihedral angles φ and ψ of the central residue. Conventionally, eight different types of β-turns have been defined, whereas those that cannot be defined are classified as type IV β-turns. This classification remains the most widely used. Nonetheless, the miscellaneous type IV β-turns represent 1/3rd of β-turn residues. An unsupervised specific clustering approach was designed to search for recurrent new turns in the type IV category. The classical rules of β-turn type assignment were central to the approach. The four most frequently occurring clusters defined the new β-turn types. Unexpectedly, these types, designated IV1, IV2, IV3 and IV4, represent half of the type IV β-turns and occur more frequently than many of the previously established types. These types show convincing particularities, in terms of both structures and sequences that allow for the classical β-turn classification to be extended for the first time in 25 years. PMID:27627963

  4. Extension of the classical classification of β-turns.

    PubMed

    de Brevern, Alexandre G

    2016-09-15

    The functional properties of a protein primarily depend on its three-dimensional (3D) structure. These properties have classically been assigned, visualized and analysed on the basis of protein secondary structures. The β-turn is the third most important secondary structure after helices and β-strands. β-turns have been classified according to the values of the dihedral angles φ and ψ of the central residue. Conventionally, eight different types of β-turns have been defined, whereas those that cannot be defined are classified as type IV β-turns. This classification remains the most widely used. Nonetheless, the miscellaneous type IV β-turns represent 1/3(rd) of β-turn residues. An unsupervised specific clustering approach was designed to search for recurrent new turns in the type IV category. The classical rules of β-turn type assignment were central to the approach. The four most frequently occurring clusters defined the new β-turn types. Unexpectedly, these types, designated IV1, IV2, IV3 and IV4, represent half of the type IV β-turns and occur more frequently than many of the previously established types. These types show convincing particularities, in terms of both structures and sequences that allow for the classical β-turn classification to be extended for the first time in 25 years.

  5. What Bed Size Does a Patient Need? The Relationship Between Body Mass Index and Space Required to Turn in Bed

    PubMed Central

    Wiggermann, Neal; Smith, Kathryn; Kumpar, Dee

    2017-01-01

    Background A bed that is too small to allow patients to turn from supine to side lying increases the difficulty of mobilizing patients, which can increase risk of musculoskeletal injury to caregivers, increase risk of pressure injuries to patients, and reduce patient comfort. Currently, no guidance is available for what patient sizes are accommodated by the standard 91cm (36 in.)-wide hospital bed, and no studies have evaluated the relationship between anthropometric attributes and space required to turn in bed. Objective The purpose of this research was to determine how much space individuals occupy when turning from supine to side lying as predicted by their anthropometry (i.e., body dimensions) to establish guidance on selecting the appropriate bed size. Methods Forty-seven adult participants (24 female) with body mass index (BMI) from 20 to 76 kg/m2 participated in a laboratory study. Body dimensions were measured, and the envelope of space required to turn was determined using motion capture. Linear regressions estimated the relationship between anthropometric attributes and space occupied when turning. Results BMI was strongly correlated (R2 = .88) with the space required to turn. Based on the linear regressions, individuals with BMI up to 35 kg/m2 could turn left and right within 91 cm and individuals with BMI up to 45 kg/m2 could turn one direction within 91 cm. Discussion BMI is a good predictor of the space required to turn from supine to lateral. Nurses should consider placing patients that are unable to laterally reposition themselves on a wider bed when BMI is greater than 35 kg/m2 and should consider placing all patients greater than 45 kg/m2 on a wider bed regardless of mobility. Hospital administrators can use historical demographic information about the BMI of their patient populations to plan facility-level equipment procurement for equipment that accommodates their patients. PMID:28968285

  6. 3. Log bunkhouse (far left), log chicken house (left of ...

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

    3. Log bunkhouse (far left), log chicken house (left of center), equipment shed (center), and workshop (far right). View to northwest. - William & Lucina Bowe Ranch, County Road 44, 0.1 mile northeast of Big Hole River Bridge, Melrose, Silver Bow County, MT

  7. DNA sequence selectivity of hairpin polyamide turn units

    PubMed Central

    Farkas, Michelle E.; Li, Benjamin C.; Dose, Christian; Dervan, Peter B.

    2011-01-01

    A class of hairpin polyamides linked by 3,4-diaminobutyric acid, resulting in a β-amine residue at the turn unit, showed improved binding affinities relative to their α-amino-γ-turn analogs for particular sequences. We incorporated β-amino-γ-turns in six-ring polyamides and determined whether there are any sequence preferences under the turn unit by quantitative footprinting titrations. Although there was an energetic penalty for G·C and C·G base pairs, we found little preference for T·A over A·T at the β-amino-γ-turn position. Fluorine and hydroxyl substituted α-amino-γ-turns were synthesized for comparison. Their binding affinities and specificities in the context of six-ring polyamides demonstrated overall diminished affinity and no additional specificity at the turn position. We anticipate that this study will be a baseline for further investigation of the turn subunit as a recognition element for the DNA minor groove. PMID:19349175

  8. Increasing protein stability by improving beta-turns.

    PubMed

    Fu, Hailong; Grimsley, Gerald R; Razvi, Abbas; Scholtz, J Martin; Pace, C Nick

    2009-11-15

    Our goal was to gain a better understanding of how protein stability can be increased by improving beta-turns. We studied 22 beta-turns in nine proteins with 66-370 residues by replacing other residues with proline and glycine and measuring the stability. These two residues are statistically preferred in some beta-turn positions. We studied: Cold shock protein B (CspB), Histidine-containing phosphocarrier protein, Ubiquitin, Ribonucleases Sa2, Sa3, T1, and HI, Tryptophan synthetase alpha-subunit, and Maltose binding protein. Of the 15 single proline mutations, 11 increased stability (Average = 0.8 +/- 0.3; Range = 0.3-1.5 kcal/mol), and the stabilizing effect of double proline mutants was additive. On the basis of this and our previous work, we conclude that proteins can generally be stabilized by replacing nonproline residues with proline residues at the i + 1 position of Type I and II beta-turns and at the i position in Type II beta-turns. Other turn positions can sometimes be used if the phi angle is near -60 degrees for the residue replaced. It is important that the side chain of the residue replaced is less than 50% buried. Identical substitutions in beta-turns in related proteins give similar results. Proline substitutions increase stability mainly by decreasing the entropy of the denatured state. In contrast, the large, diverse group of proteins considered here had almost no residues in beta-turns that could be replaced by Gly to increase protein stability. Improving beta-turns by substituting Pro residues is a generally useful way of increasing protein stability. 2009 Wiley-Liss, Inc.

  9. INCREASING PROTEIN STABILITY BY IMPROVING BETA-TURNS

    PubMed Central

    Fu, Hailong; Grimsley, Gerald R.; Razvi, Abbas; Scholtz, J. Martin; Pace, C. Nick

    2009-01-01

    Our goal was to gain a better understanding of how protein stability can be increased by improving β-turns. We studied 22 β-turns in nine proteins with 66 to 370 residues by replacing other residues with proline and glycine and measuring the stability. These two residues are statistically preferred in some β-turn positions. We studied: Cold shock protein B (CspB), Histidine-containing phosphocarrier protein (HPr), Ubiquitin, Ribonucleases Sa2, Sa3, T1, and HI, Tryptophan synthetase α-subunit (TSα), and Maltose binding protein (MBP). Of the fifteen single proline mutations, 11increased stability (Average = 0.8 ± 0.3; Range = 0.3 – 1.5 kcal/mol), and the stabilizing effect of double proline mutants was additive. Based on this and our previous work, we conclude that proteins can generally be stabilized by replacing non-proline residues with proline residues at the i + 1 position of Type I and II β-turns and at the i position in Type II β-turns. Other turn positions can sometimes be used if the φ angle is near −60° for the residue replaced. It is important that the side chain of the residue replaced is less than 50% buried. Identical substitutions in β-turns in related proteins give similar results. Proline substitutions increase stability mainly by decreasing the entropy of the denatured state. In contrast, the large, diverse group of proteins considered here had almost no residues in β-turns that could be replaced by Gly to increase protein stability. Improving β-turns by substituting Pro residues is a generally useful way of increasing protein stability. PMID:19626709

  10. Surgical management of the left superior vena cava draining into the left atrium: a novel off-pump technique using the left atrial appendage

    PubMed Central

    Boutayeb, Alaae; Marmade, Lahcen; Bensouda, Adil; Moughil, Said

    2012-01-01

    The left superior vena cava is the most common congenital venous anomaly in the chest; however, its drainage into the left atrium is exceptional. The aim of the paper is to describe our novel technique to connect the left superior vena cava to the right cavities using the left atrial appendage, without cardiopulmonary bypass. PMID:22802356

  11. Utilizing the N beam position monitor method for turn-by-turn optics measurements

    NASA Astrophysics Data System (ADS)

    Langner, A.; Benedetti, G.; Carlà, M.; Iriso, U.; Martí, Z.; de Portugal, J. Coello; Tomás, R.

    2016-09-01

    The N beam position monitor method (N -BPM) which was recently developed for the LHC has significantly improved the precision of optics measurements that are based on BPM turn-by-turn data. The main improvement is due to the consideration of correlations for statistical and systematic error sources, as well as increasing the amount of BPM combinations which are used to derive the β -function at one location. We present how this technique can be applied at light sources like ALBA, and compare the results with other methods.

  12. Flow and Heat Transfer in 180-Degree Turn Square Ducts: Effects of Turning Configuration and System Rotation

    NASA Technical Reports Server (NTRS)

    Wang, Ten-See; Chyu, Ming-King

    1993-01-01

    Forced flow through channels connected by sharp bends is frequently encountered in various rocket and gas turbine engines. For example, the transfer ducts, the coolant channels surround the combustion chamber, the internal cooling passage in a blade or vane, the flow path in the fuel element of a nuclear rocket engine, the flow around a pressure relieve valve piston, and the recirculated base flow of multiple engine clustered nozzles. Transport phenomena involved in such a flow passage are complex and considered to be very different from those of conventional turning flow with relatively mild radii of curvature. While previous research pertaining to this subject has been focused primarily on the experimental heat transfer, very little analytical work is directed to understanding the flowfield and energy transport in the passage. Therefore, the primary goal of this paper is to benchmark the predicted wall heat fluxes using a state-of-the-art computational fluid dynamics (CFD) formulation against those of measurement for a rectangular turn duct. Other secondary goals include studying the effects of turning configurations, e.g., the semi-circular turn, and the rounded-corner turn, and the effect of system rotation. The computed heat fluxes for the rectangular turn duct compared favorably with those of the experimental data. The results show that the flow pattern, pressure drop, and heat transfer characteristics are different among the three turning configurations, and are substantially different with system rotation. Also demonstrated in this work is that the present computational approach is quite effective and efficient and will be suitable for flow and thermal modeling in rocket and turbine engine applications.

  13. 6. Livestock barn (far left), log drafthorse barn (left of ...

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

    6. Livestock barn (far left), log draft-horse barn (left of center), loafing shed (center), log calving barn (right of center). View to west-northwest. - William & Lucina Bowe Ranch, County Road 44, 0.1 mile northeast of Big Hole River Bridge, Melrose, Silver Bow County, MT

  14. Repair of aorto-left ventricular tunnel arising from the left sinus of valsalva.

    PubMed

    Nezafati, Mohammad Hassan; Maleki, Mahmood Hosseinzadeh; Javan, Hadi; Zirak, Nahid

    2010-05-01

    Aortico-left ventricular tunnel (ALVT) is a rare congenital cardiac defect that bypasses the aortic valve via a para-valvular connection from the left ventricle to the aorta. In most cases, the tunnel arises from the right aortic sinus. In this case report, we are presenting a case of ALVT, of which the aortic orifice arose from the left aortic sinus, requiring special attention to avoid the left coronary artery injury at the time of surgical repair.

  15. Anticipation in turn-taking: mechanisms and information sources.

    PubMed

    Riest, Carina; Jorschick, Annett B; de Ruiter, Jan P

    2015-01-01

    During conversations participants alternate smoothly between speaker and hearer roles with only brief pauses and overlaps. There are two competing types of accounts about how conversationalists accomplish this: (a) the signaling approach and (b) the anticipatory ('projection') approach. We wanted to investigate, first, the relative merits of these two accounts, and second, the relative contribution of semantic and syntactic information to the timing of next turn initiation. We performed three button-press experiments using turn fragments taken from natural conversations to address the following questions: (a) Is turn-taking predominantly based on anticipation or on reaction, and (b) what is the relative contribution of semantic and syntactic information to accurate turn-taking. In our first experiment we gradually manipulated the information available for anticipation of the turn end (providing information about the turn end in advance to completely removing linguistic information). The results of our first experiment show that the distribution of the participants' estimation of turn-endings for natural turns is very similar to the distribution for pure anticipation. We conclude that listeners are indeed able to anticipate a turn-end and that this strategy is predominantly used in turn-taking. In Experiment 2 we collected purely reacted responses. We used the distributions from Experiments 1 and 2 together to estimate a new dependent variable called Reaction Anticipation Proportion. We used this variable in our third experiment where we manipulated the presence vs. absence of semantic and syntactic information by low-pass filtering open-class and closed class words in the turn. The results suggest that for turn-end anticipation, both semantic and syntactic information are needed, but that the semantic information is a more important anticipation cue than syntactic information.

  16. Anticipation in turn-taking: mechanisms and information sources

    PubMed Central

    Riest, Carina; Jorschick, Annett B.; de Ruiter, Jan P.

    2015-01-01

    During conversations participants alternate smoothly between speaker and hearer roles with only brief pauses and overlaps. There are two competing types of accounts about how conversationalists accomplish this: (a) the signaling approach and (b) the anticipatory (‘projection’) approach. We wanted to investigate, first, the relative merits of these two accounts, and second, the relative contribution of semantic and syntactic information to the timing of next turn initiation. We performed three button-press experiments using turn fragments taken from natural conversations to address the following questions: (a) Is turn-taking predominantly based on anticipation or on reaction, and (b) what is the relative contribution of semantic and syntactic information to accurate turn-taking. In our first experiment we gradually manipulated the information available for anticipation of the turn end (providing information about the turn end in advance to completely removing linguistic information). The results of our first experiment show that the distribution of the participants’ estimation of turn-endings for natural turns is very similar to the distribution for pure anticipation. We conclude that listeners are indeed able to anticipate a turn-end and that this strategy is predominantly used in turn-taking. In Experiment 2 we collected purely reacted responses. We used the distributions from Experiments 1 and 2 together to estimate a new dependent variable called Reaction Anticipation Proportion. We used this variable in our third experiment where we manipulated the presence vs. absence of semantic and syntactic information by low-pass filtering open-class and closed class words in the turn. The results suggest that for turn-end anticipation, both semantic and syntactic information are needed, but that the semantic information is a more important anticipation cue than syntactic information. PMID:25699004

  17. Bodily-visual practices and turn continuation

    PubMed Central

    Ford, Cecilia E.; Thompson, Sandra A.; Drake, Veronika

    2012-01-01

    This paper considers points in turn construction where conversation researchers have shown that talk routinely continues beyond possible turn completion, but where we find bodily-visual behavior doing such turn extension work. The bodily-visual behaviors we examine share many features with verbal turn extensions, but we argue that embodied movements have distinct properties that make them well-suited for specific kinds of social action, including stance display and by-play in sequences framed as subsidiary to a simultaneous and related verbal exchange. Our study is in line with a research agenda taking seriously the point made by Goodwin (2000a, b, 2003), Hayashi (2003, 2005), Iwasaki (2009), and others that scholars seeking to account for practices in language and social interaction do themselves a disservice if they privilege the verbal dimension; rather, as suggested in Stivers/Sidnell (2005), each semiotic system/modality, while coordinated with others, has its own organization. With the current exploration of bodily-visual turn extensions, we hope to contribute to a growing understanding of how these different modes of organization are managed concurrently and in concert by interactants in carrying out their everyday social actions. PMID:23526861

  18. Sharp turning and corner turning: comparison of energy expenditure, gait parameters, and level of fatigue among community-dwelling elderly.

    PubMed

    Justine, Maria; Manaf, Haidzir; Sulaiman, Affeenddie; Razi, Shahir; Alias, Hani Asilah

    2014-01-01

    This study compares energy expenditure (EE), gait parameters (GP), and level of fatigue (LOF) between 5-minute walking with sharp turning (ST) and corner turning (CT). Data were obtained from 29 community-dwelling elderly (mean age, 62.7 ± 3.54 years). For 5 minutes, in ST task, participants walked on a 3-meter pathway with 2 cones placed at each end (180° turning), while in CT task, participants walked on a 6-meter pathway with 4 cones placed at 4 corners (90° turning). The physiological cost index, pedometer, and 10-point Modified Borg Dyspnoea Scale were used to measure EE (beats/min), GP (no of steps), and LOF, respectively. Data were analyzed by using independent t-tests. EE during ST (0.62 ± 0.21 beats/min) was significantly higher than CT (0.48 ± 0.17 beats/min) (P < 0.05). GP (434 ± 92.93 steps) and LOF (1.40 ± 1.11) in ST were found to be lower compared to GP (463 ± 92.18 steps) and LOF (1.54 ± 1.34) in CT (All, P > 0.05). Higher EE in ST could be due to the difficulty in changing to a 180° direction, which may involve agility and different turning strategies (step-turn or pivot-turn) to adjust the posture carefully. In CT, participants could choose a step-turn strategy to change to a 90° direction, which was less challenging to postural control.

  19. What's Left of the Left-Right Dimension? Why the Economic Policy Positions of Europeans Do Not Fit the Left-Right Dimension.

    PubMed

    Otjes, Simon

    2018-01-01

    In political science the economic left-right dimension plays a central role. A growing body of evidence shows that the economic policy preferences of a large segment of citizens do not scale sufficiently. Using Mokken scale analysis, this study determines the causes of this phenomenon. Differences in the extent to which the economic policy preferences of citizens fit the left-right dimension can be explained in terms of the interaction between individual level and political system-level variables: citizens who spend more attention to politicians with views that conform to the left-right dimension, have views that conform to the left-right dimension. There is also a role for the legacy of communist dictatorship: citizens who were socialised in democratic countries have views that fit the left-right dimension better than those socialised during communism.

  20. Anatomic relationship between left coronary artery and left atrium in patients undergoing atrial fibrillation ablation.

    PubMed

    Anselmino, Matteo; Torri, Federica; Ferraris, Federico; Calò, Leonardo; Castagno, Davide; Gili, Sebastiano; Rovera, Chiara; Giustetto, Carla; Gaita, Fiorenzo

    2017-07-01

    Atrial fibrillation transcatheter ablation (TCA) is, within available atrial fibrillation rhythm control strategies, one of the most effective. To potentially improve ablation outcome in case of recurrent atrial fibrillation after a first procedure or in presence of structural myocardial disease, isolation of the pulmonary veins may be associated with extensive lesions within the left atrium. To avoid rare, but potentially life-threatening, complications, thorough knowledge and assessment of left atrium anatomy and its relation to structures in close proximity are, therefore, mandatory. Aim of the present study is to describe, by cardiac computed tomography, the anatomic relationship between aortic root, left coronary artery and left atrium in patients undergoing atrial fibrillation TCA. The cardiac computed tomography scan of 21 patients affected by atrial fibrillation was elaborated to segment left atrium, aortic root and left coronary artery from the surrounding structures and the following distances measured: left atrium and aortic root; left atrium roof and aortic root; left main coronary artery and left atrium; circumflex artery and left atrium appendage; and circumflex artery and mitral valve annulus. Above all, the median distance between left atrium and aortic root (1.9, 1.5-2.1 mm), and between circumflex artery and left atrium appendage ostium (3.0, 2.1-3.4 mm) were minimal (≤3 mm). None of measured distances significantly varied between patients presenting paroxysmal versus persistent atrial fibrillation. The anatomic relationship between left atrium and coronary arteries is extremely relevant when performing atrial fibrillation TCA by extensive lesions. Therefore, at least in the latter case, preablation imaging should be recommended to avoid rare, but potentially life-threatening, complications with the aim of an as well tolerated as possible procedure.

  1. 1. Postandbeam garage (far left), oneroom log cabin (left of ...

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

    1. Post-and-beam garage (far left), one-room log cabin (left of center), house (right of center), garden shed and outhouse (far right). View to west-southwest. - William & Lucina Bowe Ranch, County Road 44, 0.1 mile northeast of Big Hole River Bridge, Melrose, Silver Bow County, MT

  2. PHOTOGRAPHER: KSC The first solid rocket booster solid motor segemnts to arrive at KSC, the left and

    NASA Technical Reports Server (NTRS)

    1980-01-01

    PHOTOGRAPHER: KSC The first solid rocket booster solid motor segemnts to arrive at KSC, the left and right hand aft segments are off-loaded into High Bay 4 in the Vehicle Assembly Building and mated to their respective SRB aft skirts. The two aft assemblies will support the entire 150 foot tall solid boosters, in turn supporting the external tank and Orbiter Columbia on the Mobile Launcher Platform, for the first orbital flight test of the Space Shuttle.

  3. Photographer: KSC The first solid rocket booster solid motor segemnts to arrive at KSC, the left and

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Photographer: KSC The first solid rocket booster solid motor segemnts to arrive at KSC, the left and right hand aft segments are off-loaded into High Bay 4 in the Vehicle Assembly Building and mated to their respective SRB aft skirts. The two aft assemblies will support the entire 150 foot tall solid boosters, in turn supporting the external tank and Orbiter Columbia on the Mobile Launcher Platform, for the first orbital flight test of the Space Shuttle.

  4. Right-Turn Lanes

    DOT National Transportation Integrated Search

    1996-05-01

    The following topics are the subjects of this discussion paper. : 1. Should right-turn deceleration lanes be provided? On Oregon : highways? If so, what warrants are to be used? When, if : provided, how should the length be determined? : 2. Should ri...

  5. Mapping of the left-sided phrenic nerve course in patients undergoing left atrial catheter ablations.

    PubMed

    Huemer, Martin; Wutzler, Alexander; Parwani, Abdul S; Attanasio, Philipp; Haverkamp, Wilhelm; Boldt, Leif-Hendrik

    2014-09-01

    Catheter ablation of atrial fibrillation has been associated with left-sided phrenic nerve palsy. Knowledge of the individual left phrenic nerve course therefore is essential to prevent nerve injury. The aim of this study was to test the feasibility of an intraprocedural pace mapping and reconstruction of the left phrenic nerve course and to characterize which anatomical areas are affected. In patients undergoing left atrial catheter ablation, a three-dimensional map of the left atrial anatomical structures was created. The left-sided phrenic nerve course was determined by high-output pace mapping and reconstructed in the map. In this study, 40 patients with atrial fibrillation or atrial tachycardias were included. Left phrenic nerve capture was observed in 23 (57.5%) patients. Phrenic nerve was captured in 22 (55%) patients inside the left atrial appendage, in 22 (55%) in distal parts, in 21 (53%) in medial parts, and in two (5%) in ostial parts of the appendage. In three (7.5%) patients, capture was found in the distal coronary sinus and in one (2.5%) patient in the left atrium near the left atrial appendage ostium. Ablation target was changed due to direct spatial relationship to the phrenic nerve in three (7.5%) patients. No phrenic nerve palsy was observed. Left-sided phrenic nerve capture was found inside and around the left atrial appendage in the majority of patients and additionally in the distal coronary sinus. Phrenic nerve mapping and reconstruction can easily be performed and should be considered prior catheter ablations in potential affected areas. ©2014 Wiley Periodicals, Inc.

  6. Validation of PEP-II Resonantly Excited Turn-by-Turn BPM Data

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

    Yan, Yiton T.; Cai, Yunhai; Colocho, William.

    2007-06-28

    For optics measurement and modeling of the PEP-II electron (HER) and position (LER) storage rings, we have been doing well with MIA [1] which requires analyzing turn-by-turn Beam Position Monitor (BPM) data that are resonantly excited at the horizontal, vertical, and longitudinal tunes. However, in anticipation that certain BPM buttons and even pins in the PEP-II IR region would be missing for the run starting in January 2007, we had been developing a data validation process to reduce the effect due to the reduced BPM data accuracy on PEP-II optics measurement and modeling. Besides the routine process for ranking BPMmore » noise level through data correlation among BPMs with a singular-value decomposition (SVD), we could also check BPM data symplecticity by comparing the invariant ratios. Results from PEP-II measurement will be presented.« less

  7. Turning for Ulcer Reduction (TURN) Study: An Economic Analysis.

    PubMed

    Paulden, Mike; Bergstrom, Nancy; Horn, Susan D; Rapp, Mary; Stern, Anita; Barrett, Ryan; Watkiss, Michael; Krahn, Murray

    2014-01-01

    The Turning for Ulcer Reduction (TURN) study was a multisite, randomized controlled trial that aimed to determine the optimal frequency of turning nursing facility residents with mobility limitations who are at moderate and high risk for pressure ulcer (PrU) development. Here we present data from the economic analysis. This economic analysis aims to estimate the economic consequences for Ontario of switching from a repositioning schedule of 2-hour intervals to a schedule of 3-hour or 4-hour intervals. Costs considered in the analysis included those associated with nursing staff time spent repositioning residents and with incontinent care supplies, which included briefs, barrier cream, and washcloths. The total economic benefit of switching to 3-hour or 4-hour repositioning is estimated to be $11.05 or $16.74 per day, respectively, for every resident at moderate or high risk of developing PrUs. For a typical facility with 123 residents, 41 (33%) of whom are at moderate or high risk of developing PrUs, the total economic benefit is estimated to be $453 daily for 3-hour or $686 daily for 4-hour repositioning. For Ontario as a whole, assuming that there are 77,933 residents at 634 LTC facilities, 25,927 (33%) of whom are at moderate or high risk of developing PrUs, the total economic benefits of switching to 3-hour or 4-hour repositioning are estimated to be $286,420 or $433,913 daily, respectively, equivalent to $104.5 million or $158.4 million per year. We did not consider the savings the Ontario Ministry of Health and Long-Term Care might incur should less frequent repositioning reduce the incidence of work-related injury among nursing staff, so our findings are potentially conservative. A switch to 3-hour or 4-hour repositioning appears likely to yield substantial economic benefits to Ontario without placing residents at greater risk of developing PrUs.

  8. Turning for Ulcer Reduction (TURN) Study: An Economic Analysis

    PubMed Central

    Paulden, Mike; Bergstrom, Nancy; Horn, Susan D.; Rapp, Mary; Stern, Anita; Barrett, Ryan; Watkiss, Michael; Krahn, Murray

    2014-01-01

    Background The Turning for Ulcer Reduction (TURN) study was a multisite, randomized controlled trial that aimed to determine the optimal frequency of turning nursing facility residents with mobility limitations who are at moderate and high risk for pressure ulcer (PrU) development. Here we present data from the economic analysis. Objectives This economic analysis aims to estimate the economic consequences for Ontario of switching from a repositioning schedule of 2-hour intervals to a schedule of 3-hour or 4-hour intervals. Data Sources Costs considered in the analysis included those associated with nursing staff time spent repositioning residents and with incontinent care supplies, which included briefs, barrier cream, and washcloths. Results The total economic benefit of switching to 3-hour or 4-hour repositioning is estimated to be $11.05 or $16.74 per day, respectively, for every resident at moderate or high risk of developing PrUs. For a typical facility with 123 residents, 41 (33%) of whom are at moderate or high risk of developing PrUs, the total economic benefit is estimated to be $453 daily for 3-hour or $686 daily for 4-hour repositioning. For Ontario as a whole, assuming that there are 77,933 residents at 634 LTC facilities, 25,927 (33%) of whom are at moderate or high risk of developing PrUs, the total economic benefits of switching to 3-hour or 4-hour repositioning are estimated to be $286,420 or $433,913 daily, respectively, equivalent to $104.5 million or $158.4 million per year. Limitations We did not consider the savings the Ontario Ministry of Health and Long-Term Care might incur should less frequent repositioning reduce the incidence of work-related injury among nursing staff, so our findings are potentially conservative. Conclusions A switch to 3-hour or 4-hour repositioning appears likely to yield substantial economic benefits to Ontario without placing residents at greater risk of developing PrUs. PMID:26330894

  9. Turning crocodilian hearts into bird hearts: growth rates are similar for alligators with and without right-to-left cardiac shunt

    PubMed Central

    Eme, John; Gwalthney, June; Owerkowicz, Tomasz; Blank, Jason M.; Hicks, James W.

    2010-01-01

    The functional and possible adaptive significance of non-avian reptiles' dual aortic arch system and the ability of all non-avian reptiles to perform central vascular cardiac shunts have been of great interest to comparative physiologists. The unique cardiac anatomy of crocodilians – a four-chambered heart with the dual aortic arch system – allows for only right-to-left (R–L; pulmonary bypass) cardiac shunt and for surgical elimination of this shunt. Surgical removal of the R–L shunt, by occluding the left aorta (LAo) upstream and downstream of the foramen of Panizza, results in a crocodilian with an obligatory, avian/mammalian central circulation. In this study, R–L cardiac shunt was eliminated in age-matched, female American alligators (Alligator mississippiensis; 5–7 months of age). We tested the hypothesis that surgical elimination of R–L cardiac shunt would impair growth (a readily measured proxy for fitness) compared with sham-operated, age-matched controls, especially in animals subjected to exhaustive exercise. While regular exercise caused a decrease in size (snout-to-vent length, head length and body mass), elimination of the capacity for R–L cardiac shunt did not greatly reduce animal growth, despite a chronic ventricular enlargement in surgically altered juvenile alligators. We speculate that, despite being slightly smaller, alligators with an occluded LAo would have reached sexual maturity in the same breeding season as control alligators. This study suggests that crocodilian R–L cardiac shunt does not provide an adaptive advantage for juvenile alligator growth and supports the logic that cardiac shunts persist in crocodilians because they have not been selected against. PMID:20639429

  10. ACCELERATORS: Preliminary application of turn-by-turn data analysis to the SSRF storage ring

    NASA Astrophysics Data System (ADS)

    Chen, Jian-Hui; Zhao, Zhen-Tang

    2009-07-01

    There is growing interest in utilizing the beam position monitor turn-by-turn (TBT) data to debug accelerators. TBT data can be used to determine the linear optics, coupled optics and nonlinear behaviors of the storage ring lattice. This is not only a useful complement to other methods of determining the linear optics such as LOCO, but also provides a possibility to uncover more hidden phenomena. In this paper, a preliminary application of a β function measurement to the SSRF storage ring is presented.

  11. L-shaped right-to-left crossed-fused renal ectopia with left dysplastic ureter.

    PubMed

    Song, Wei; Yang, Jinrui; Zhu, Liang; Liu, Longfei

    2012-01-01

    Crossed-fused renal ectopia is a relatively rare congenital malformation. Herein, we report a case of L-shaped right- to-left crossed-fused renal ectopia with a left dysplastic ureter in a 5-year-old girl. She underwent a left nephrectomy and the postoperative course was uneventful. Copyright © 2011 S. Karger AG, Basel.

  12. Primordial spectra from sudden turning trajectory

    NASA Astrophysics Data System (ADS)

    Noumi, Toshifumi; Yamaguchi, Masahide

    2013-12-01

    Effects of heavy fields on primordial spectra of curvature perturbations are discussed in inflationary models with a sudden turning trajectory. When heavy fields are excited after the sudden turn and oscillate around the bottom of the potential, the following two effects are generically induced: deformation of the inflationary background spacetime and conversion interactions between adiabatic and isocurvature perturbations, both of which can affect the primordial density perturbations. In this paper, we calculate primordial spectra in inflationary models with sudden turning potentials taking into account both of the two effects appropriately. We find that there are some non-trivial correlations between the two effects in the power spectrum and, as a consequence, the primordial scalar power spectrum has a peak around the scale exiting the horizon at the turn. Though both effects can induce parametric resonance amplifications, they are shown to be canceled out for the case with the canonical kinetic terms. The peak feature and the scale dependence of bispectra are also discussed.

  13. Which Cheek did the Resurrected Jesus Turn?

    PubMed

    Acosta, Lealani Mae Y; Williamson, John B; Heilman, Kenneth M

    2015-06-01

    Secular portraits are likely to show more of the left than right side of the face (hemiface). Prior research has shown that emotions are more strongly expressed by the left hemiface. In addition, the valence theory of emotion proposes that the right hemisphere is dominant for mediating negative emotions, and the left hemisphere for positive emotions. Since religious art depicting a scene such as the Resurrection of Jesus is more likely to be associated with positive emotions, we postulated that there would be a significant smaller percentage number of artistic works of the Resurrection that reveal the left side of the face of Jesus than in those art works portraying the Crucifixion. Thus, we analyzed artistic portrayals of the Resurrection of Jesus and compared them to the artistic scenes of the Crucifixion. This analysis revealed that the left side of the face of Jesus is less commonly depicted in portraits of the Resurrection than the Crucifixion. In addition, both the right hemiface, and forward-facing faces were also more commonly portrayed in painting of the Resurrection than the Crucifixion. Whereas this right-left hemiface, Resurrection-Crucifixion dichotomy may be related to right-left hemispheric difference in the mediation of emotional valence other factors such as agency, action-intention, and biblical text may have influenced these differences.

  14. Identification of a key structural element for protein folding within beta-hairpin turns.

    PubMed

    Kim, Jaewon; Brych, Stephen R; Lee, Jihun; Logan, Timothy M; Blaber, Michael

    2003-05-09

    Specific residues in a polypeptide may be key contributors to the stability and foldability of the unique native structure. Identification and prediction of such residues is, therefore, an important area of investigation in solving the protein folding problem. Atypical main-chain conformations can help identify strains within a folded protein, and by inference, positions where unique amino acids may have a naturally high frequency of occurrence due to favorable contributions to stability and folding. Non-Gly residues located near the left-handed alpha-helical region (L-alpha) of the Ramachandran plot are a potential indicator of structural strain. Although many investigators have studied mutations at such positions, no consistent energetic or kinetic contributions to stability or folding have been elucidated. Here we report a study of the effects of Gly, Ala and Asn substitutions found within the L-alpha region at a characteristic position in defined beta-hairpin turns within human acidic fibroblast growth factor, and demonstrate consistent effects upon stability and folding kinetics. The thermodynamic and kinetic data are compared to available data for similar mutations in other proteins, with excellent agreement. The results have identified that Gly at the i+3 position within a subset of beta-hairpin turns is a key contributor towards increasing the rate of folding to the native state of the polypeptide while leaving the rate of unfolding largely unchanged.

  15. Specific β-Turns Precede PPIIL Structures Binding to Allele-Specific HLA-DRβ1* PBRs in Fully-Protective Malaria Vaccine Components

    PubMed Central

    Bermudez, Adriana; Alba, Martha P.; Vanegas, Magnolia; Patarroyo, Manuel A.; Patarroyo, Manuel E.

    2018-01-01

    The 3D structural analysis of 62 peptides derived from highly pathogenic Plasmodium falciparum malaria parasite proteins involved in host cell invasion led to finding a striking association between particular β-turn types located in the N-terminal peripheral flanking residue region (preceding the polyproline II left-handed structures fitting into the HLA-DRβ* allele family) and modified immune protection-inducing protein structure induced long-lasting protective immunity. This is the first time association between two different secondary structures associated with a specific immunological function has been described: full, long-lasting protective immunity. PMID:29682500

  16. Specific β-Turns Precede PPIIL Structures Binding to Allele-Specific HLA-DRβ1* PBRs in Fully-Protective Malaria Vaccine Components.

    PubMed

    Bermudez, Adriana; Alba, Martha P; Vanegas, Magnolia; Patarroyo, Manuel A; Patarroyo, Manuel E

    2018-01-01

    The 3D structural analysis of 62 peptides derived from highly pathogenic Plasmodium falciparum malaria parasite proteins involved in host cell invasion led to finding a striking association between particular β-turn types located in the N-terminal peripheral flanking residue region (preceding the polyproline II left-handed structures fitting into the HLA-DRβ * allele family) and modified i mmune protection-inducing protein structure induced long-lasting protective immunity. This is the first time association between two different secondary structures associated with a specific immunological function has been described: full, long-lasting protective immunity.

  17. Specific β-turns precede PPIIL structures binding to allele-specific HLA-DRβ1* PBRs in fully-protective malaria vaccine components

    NASA Astrophysics Data System (ADS)

    Bermudez, Adriana; Alba, Martha P.; Vanegas, Magnolia; Patarroyo, Manuel A.; Patarroyo, Manuel E.

    2018-04-01

    The 3D structural analysis of 62 peptides derived from highly pathogenic Plasmodium falciparum malaria parasite proteins involved in host cell invasion led to finding a striking association between particular β-turn types located in the N-terminal peripheral flanking residue region (preceding the polyproline II left-handed structures fitting into the HLA-DRβ* allele family) and modified immune protection-inducing protein structure induced long-lasting protective immunity. This is the first time association between two different secondary structures associated with a specific immunological function has been described: full, long-lasting protective immunity.

  18. Revisiting the left-wing response to sociobiology: the case of Finland in a European context.

    PubMed

    Lepistö, Antti

    2015-01-01

    This article revisits the left-wing response to sociobiology in the 1970s and 1980s by examining the sociobiology debate in Finland in a larger European context. It argues that the Finnish academic left's response to sociobiology represents a "third way" alongside the purely negative, often Marxist denial of biology's relevance, which characterized the left's response to sociobiology in many European countries such as Hungary and Sweden, and alongside the disregard that sociobiology confronted in most parts of Eastern Europe, as well as in Germany. In the context of the last great political conflict of the Cold War in Europe, the controversy over the American "Euromissiles" (Pershing II and Tomahawk) in 1979-1983, the Finnish academic left challenged the allegedly fatalistic sociobiological aggression and war theories with an alternative biological language, turning the increasing enthusiasm over evolutionary ideas into a pacifist cause. Using leftist and pacifist forums to inform citizens and politicians of such biologically evolved human characteristics as mutual care and sociability, the Finnish critics of sociobiology wished to boost the public spirit, and to rationalize the pacifist ideal of the European-wide popular movement against nuclear weapons and militarism. As a result, the academic leftists in Finland revived the early twentieth-century tradition of "peace biology." A proper understanding of this development calls for an analysis that acknowledges Finland's special geopolitical and cultural position in the Cold War world between East and West.

  19. Left-Deviating Prism Adaptation in Left Neglect Patient: Reflexions on a Negative Result

    PubMed Central

    Luauté, Jacques; Jacquin-Courtois, Sophie; O'Shea, Jacinta; Christophe, Laure; Rode, Gilles; Boisson, Dominique; Rossetti, Yves

    2012-01-01

    Adaptation to right-deviating prisms is a promising intervention for the rehabilitation of patients with left spatial neglect. In order to test the lateral specificity of prism adaptation on left neglect, the present study evaluated the effect of left-deviating prism on straight-ahead pointing movements and on several classical neuropsychological tests in a group of five right brain-damaged patients with left spatial neglect. A group of healthy subjects was also included for comparison purposes. After a single session of exposing simple manual pointing to left-deviating prisms, contrary to healthy controls, none of the patients showed a reliable change of the straight-ahead pointing movement in the dark. No significant modification of attentional paper-and-pencil tasks was either observed immediately or 2 hours after prism adaptation. These results suggest that the therapeutic effect of prism adaptation on left spatial neglect relies on a specific lateralized mechanism. Evidence for a directional effect for prism adaptation both in terms of the side of the visuomanual adaptation and therefore possibly in terms of the side of brain affected by the stimulation is discussed. PMID:23050168

  20. Turning rice meiosis into mitosis

    PubMed Central

    Mieulet, Delphine; Jolivet, Sylvie; Rivard, Maud; Cromer, Laurence; Vernet, Aurore; Mayonove, Pauline; Pereira, Lucie; Droc, Gaëtan; Courtois, Brigitte; Guiderdoni, Emmanuel; Mercier, Raphael

    2016-01-01

    Introduction of clonal reproduction through seeds (apomixis) in crops has the potential to revolutionize agriculture by allowing self-propagation of any elite variety, in particular F1 hybrids. In the sexual model plant Arabidopsis thaliana synthetic clonal reproduction through seeds can be artificially implemented by (i) combining three mutations to turn meiosis into mitosis (MiMe) and (ii) crossing the obtained clonal gametes with a line expressing modified CENH3 and whose genome is eliminated in the zygote. Here we show that additional combinations of mutations can turn Arabidopsis meiosis into mitosis and that a combination of three mutations in rice (Oryza sativa) efficiently turns meiosis into mitosis, leading to the production of male and female clonal diploid gametes in this major crop. Successful implementation of the MiMe technology in the phylogenetically distant eudicot Arabidopsis and monocot rice opens doors for its application to any flowering plant and paves the way for introducing apomixis in crop species. PMID:27767093

  1. Magnetic substorms and northward IMF turning

    NASA Astrophysics Data System (ADS)

    Troshichev, Oleg; Podorozhkina, Nataly

    To determine the relation of the northward IMF turnings to substorm sudden onsets, we separated all events with sharp northward IMF turnings observed in years of solar maximum (1999-2002) and solar minimum (2007-2008). The events (N=261) have been classified in 5 groups in accordance with average magnetic activity in auroral zone (low, moderate or high levels of AL index) at unchanged or slightly changed PC index and with dynamics of PC (steady distinct growth or distinct decline) at arbitrary values of AL index. Statistical analysis of relationships between the IMF turning and changes of PC and AL indices has been fulfilled separately for each of 5 classes. Results of the analysis showed that, irrespective of geophysical conditions and solar activity epoch, the magnetic activity in the polar caps and in the auroral zone demonstrate no response to the sudden northward IMF turning, if the moment of northward turning is taken as a key date. Sharp increases of magnetic disturbance in the auroral zone are observed only under conditions of the growing PC index and statistically they are related to moment of the PC index exceeding the threshold level (~1.5 mV/m), not to northward turnings timed, as a rule, after the moment of sudden onset. Magnetic disturbances observed in these cases in the auroral zone (magnetic substorms) are guided by behavior of the PC index, like to ordinary magnetic substorms or substorms developed under conditions of the prolonged northward IMF impact on the magnetosphere. The evident inconsistency between the sharp IMF changes measured outside of the magnetosphere and behavior of the ground-based PC index, the latter determining the substorm development, provides an additional argument in favor of the PC index as a ground-based proxy of the solar wind energy that entered into magnetosphere.

  2. Hypoplastic left heart syndrome (image)

    MedlinePlus

    Hypoplastic left heart syndrome is a congenital heart condition that occurs during the development of the heart in the ... womb. During the heart's development, parts of the left side of the heart (mitral valve, left ventricle ...

  3. 33 CFR 164.42 - Rate of turn indicator.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Rate of turn indicator. 164.42...) PORTS AND WATERWAYS SAFETY NAVIGATION SAFETY REGULATIONS § 164.42 Rate of turn indicator. Each vessel of... turn indicator. [CGD 83-004, 49 FR 43468, Oct. 29, 1984] ...

  4. 33 CFR 164.42 - Rate of turn indicator.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Rate of turn indicator. 164.42...) PORTS AND WATERWAYS SAFETY NAVIGATION SAFETY REGULATIONS § 164.42 Rate of turn indicator. Each vessel of... turn indicator. [CGD 83-004, 49 FR 43468, Oct. 29, 1984] ...

  5. [Study of beta-turns in globular proteins].

    PubMed

    Amirova, S R; Milchevskiĭ, Iu V; Filatov, I V; Esipova, N G; Tumanian, V G

    2005-01-01

    The formation of beta-turns in globular proteins has been studied by the method of molecular mechanics. Statistical method of discriminant analysis was applied to calculate energy components and sequences of oligopeptide segments, and after this prediction of I type beta-turns has been drawn. The accuracy of true positive prediction is 65%. Components of conformational energy considerably affecting beta-turn formation were delineated. There are torsional energy, energy of hydrogen bonds, and van der Waals energy.

  6. TMS over the Left Angular Gyrus Impairs the Ability to Discriminate Left from Right

    ERIC Educational Resources Information Center

    Hirnstein, Marco; Bayer, Ulrike; Ellison, Amanda; Hausmann, Markus

    2011-01-01

    The underlying cognitive and neural mechanisms of the ability to discriminate left from right are hardly explored. Clinical studies from patients with impairments of left-right discrimination (LRD) and neuroimaging data suggest that the left angular gyrus is particularly involved in LRD. Moreover, it is argued that the often reported sex…

  7. Page turning solutions for musicians: a survey.

    PubMed

    Wolberg, George; Schipper, Irene

    2012-01-01

    Musicians have long been hampered by the challenge in turning sheet music while their hands are occupied playing an instrument. The sight of a human page turner assisting a pianist during a performance, for instance, is not uncommon. This need for a page turning solution is no less acute during practice sessions, which account for the vast majority of playing time. Despite widespread appreciation of the problem, there have been virtually no robust and affordable products to assist the musician. Recent progress in assistive technology and electronic reading devices offers promising solutions to this long-standing problem. The objective of this paper is to survey the technology landscape and assess the benefits and drawbacks of page turning solutions for musicians. A full range of mechanical and digital page turning products are reviewed.

  8. Experimental Hydrodynamics of Turning Maneuvers in Koi Carps

    NASA Astrophysics Data System (ADS)

    Wu, G. H.; Yang, Y.; Zeng, L. J.

    Experimental hydrodynamics of two types of turning maneuvers in koi carps (cyprinus carpio koi) are studied. The flow patterns generated by koi carps during turning are quantified by using digital particle image velocimetry. Based on the velocity fields measured, the momentums in the wake and the impulsive moments exerted on the carps are estimated. On the other hand, turning rates and radii, and moments of inertia of the carps including added mass during turning are obtained by processing the images recorded. Comparisons of the impulsive moments and moments of inertia show good agreements.

  9. STS-92 Mission Specialist Wakata takes his turn driving the M-113

    NASA Technical Reports Server (NTRS)

    2000-01-01

    With Capt. George Hoggard, trainer with the KSC Fire Department, riding on top, Mission Specialist Koichi Wakata of Japan practices driving the M-113, part of emergency egress training during Terminal Countdown Demonstration Test (TCDT) activities. Riding in the back (on the left) are other crew members, waiting their turn to drive. The tracked vehicle could be used by the crew in the event of an emergency at the pad during which the crew must make a quick exit from the area. The TCDT also provides simulated countdown exercises and opportunities to inspect the mission payloads in the orbiter's payload bay. STS-92 is scheduled to launch Oct. 5 at 9:30 p.m. EDT on the fifth flight to the International Space Station. It will carry two elements of the Space Station, the Integrated Truss Structure Z1 and the third Pressurized Mating Adapter. The mission is also the 100th flight in the Shuttle program.

  10. STS-92 Mission Specialist Wakata completes his turn driving the M-113

    NASA Technical Reports Server (NTRS)

    2000-01-01

    STS-92 Mission Specialist Koichi Wakata of Japan signals a successful driving lesson on the M-113 he is in. Capt. George Hoggard, trainer with the KSC Fire Department, sits on top. Behind Wakata are Commander Brian Duffy (left) and Leroy Chiao (right), waiting their turns. The practice drive is part of emergency egress training during Terminal Countdown Demonstration Test (TCDT) activities. The tracked vehicle could be used by the crew in the event of an emergency at the pad during which the crew must make a quick exit from the area. The TCDT also provides simulated countdown exercises and opportunities to inspect the mission payloads in the orbiter's payload bay. STS-92 is scheduled to launch Oct. 5 at 9:30 p.m. EDT on the fifth flight to the International Space Station. It will carry two elements of the Space Station, the Integrated Truss Structure Z1 and the third Pressurized Mating Adapter. The mission is also the 100th flight in the Shuttle program.

  11. Multiple left anterior descending coronary artery to left ventricular fistula - A case series and literature review.

    PubMed

    Iyer, Praneet; Yelisetti, Rishitha

    2017-10-01

    Coronary artery fistulas (CAFs) are found in 0.3-0.8% of patients who undergo coronary angiography. CAFs are defined as single or multiple, small or large direct communications that arise from one or more coronary arteries and enter into one of the four cardiac chambers or major vessels. We present two cases of multiple coronary artery fistulas arising from diagonal and left anterior descending (LAD) branches of left coronary artery draining into the left ventricle. In both the cases, No intervention was performed. Of the congenital fistulas, two major groups are identified: solitary CAFs or coronary artery-left ventricular multiple micro-fistulas (CALVMMFs). Noninvasive techniques such as transthoracic echocardiography, transesophageal echocardiography and magnetic resonance imaging are becoming increasingly popular for diagnosis and follow-up of CAFs. Despite the advent of these newer non-invasive modalities, coronary angiography remains the gold standard for diagnosis. Treatment of CAFs is indicated when the patients are symptomatic with left ventricular volume overload, myocardial ischemia, left ventricular dysfunction or in the presence of a large or increasing left-to-right shunt. If the fistula is small and hemodynamically insignificant, it can be managed with conservative management. Multiple left anterior descending to left ventricle (LV) fistulas are extremely rare and, as per our literature review, we noted only a few case reports of coronary artery fistulas between branches of LAD and left ventricle.

  12. Impact of left atrial volume reduction concomitant with atrial fibrillation surgery on left atrial geometry and mechanical function.

    PubMed

    Marui, Akira; Saji, Yoshiaki; Nishina, Takeshi; Tadamura, Eiji; Kanao, Shotaro; Shimamoto, Takeshi; Sasahashi, Nozomu; Ikeda, Tadashi; Komeda, Masashi

    2008-06-01

    Left atrial geometry and mechanical functions exert a profound effect on left ventricular filling and overall cardiovascular performance. We sought to investigate the perioperative factors that influence left atrial geometry and mechanical functions after the Maze procedure in patients with refractory atrial fibrillation and left atrial enlargement. Seventy-four patients with atrial fibrillation and left atrial enlargement (diameter > or = 60 mm) underwent the Maze procedure in association with mitral valve surgery. The maximum left atrial volume and left atrial mechanical functions (booster pump, reservoir, and conduit function [%]) were calculated from the left atrial volume-cardiac cycle curves obtained by magnetic resonance imaging. A stepwise multiple regression analysis was performed to determine the independent variables that influenced the postoperative left atrial geometry and function. The multivariate analysis showed that left atrial reduction surgery concomitant with the Maze procedure and the postoperative maintenance of sinus rhythm were predominant independent variables for postoperative left atrial geometry and mechanical functions. Among the 58 patients who recovered sinus rhythm, the postoperative left atrial geometry and function were compared between patients with (VR group) and without (control group) left atrial volume reduction. At a mean follow-up period of 13.8 months, sinus rhythm recovery rate was better (85% vs 68%, P < .05) in the VR group and maximum left atrial volume was less (116 +/- 25 mL vs 287 +/- 73 mL, P < .001) than in the control group. The maximum left atrial volume reduced with time only in the VR group (reverse remodeling). Postoperative booster pump and reservoir function in the VR group were better than in the control group (25% +/- 6% vs 11% +/- 4% and 34% +/- 7% vs 16% +/- 4%, respectively, P < .001), whereas the conduit function in the VR group was lower than in the control group, indicating that the improvement of

  13. Estimating intersection turning movements.

    DOT National Transportation Integrated Search

    1999-05-01

    Turning movement (TM) counts are used for a variety of intersection analyses, including traffic operations analyses, : intersection design, and transportation planning applications. For many planning and design applications, especially in the case of...

  14. Left atrial extension of hepatoblastoma via left superior pulmonary vein.

    PubMed

    Atalay, Atakan; Gocen, Uğur; Yaliniz, Hafize

    2014-10-01

    Hepatoblastoma is the most common malignant liver tumour in early childhood. The metastatic extension of hepatoblastoma into the left atrium via the pulmonary vein is rare. Reported lesions almost always involve a right-sided approach. Here we report the case of a 3-year-old girl with a recurrent hepatoblastoma at multiple sites, including the left atrium, brain, and lung. The patient was treated surgically for the prevention of further embolic complications and cardiac failure.

  15. Dyscalculia, dysgraphia, and left-right confusion from a left posterior peri-insular infarct.

    PubMed

    Bhattacharyya, S; Cai, X; Klein, J P

    2014-01-01

    The Gerstmann syndrome of dyscalculia, dysgraphia, left-right confusion, and finger agnosia is generally attributed to lesions near the angular gyrus of the dominant hemisphere. A 68-year-old right-handed woman presented with sudden difficulty completing a Sudoku grid and was found to have dyscalculia, dysgraphia, and left-right confusion. Magnetic resonance imaging (MRI) showed a focus of abnormal reduced diffusivity in the left posterior insula and temporoparietal operculum consistent with acute infarct. Gerstmann syndrome from an insular or peri-insular lesion has not been described in the literature previously. Pathological and functional imaging studies show connections between left posterior insular region and inferior parietal lobe. We postulate that the insula and operculum lesion disrupted key functional networks resulting in a pseudoparietal presentation.

  16. Dyscalculia, Dysgraphia, and Left-Right Confusion from a Left Posterior Peri-Insular Infarct

    PubMed Central

    Bhattacharyya, S.; Cai, X.; Klein, J. P.

    2014-01-01

    The Gerstmann syndrome of dyscalculia, dysgraphia, left-right confusion, and finger agnosia is generally attributed to lesions near the angular gyrus of the dominant hemisphere. A 68-year-old right-handed woman presented with sudden difficulty completing a Sudoku grid and was found to have dyscalculia, dysgraphia, and left-right confusion. Magnetic resonance imaging (MRI) showed a focus of abnormal reduced diffusivity in the left posterior insula and temporoparietal operculum consistent with acute infarct. Gerstmann syndrome from an insular or peri-insular lesion has not been described in the literature previously. Pathological and functional imaging studies show connections between left posterior insular region and inferior parietal lobe. We postulate that the insula and operculum lesion disrupted key functional networks resulting in a pseudoparietal presentation. PMID:24817791

  17. Apraxia in left-handers.

    PubMed

    Goldenberg, Georg

    2013-08-01

    In typical right-handed patients both apraxia and aphasia are caused by damage to the left hemisphere, which also controls the dominant right hand. In left-handed subjects the lateralities of language and of control of the dominant hand can dissociate. This permits disentangling the association of apraxia with aphasia from that with handedness. Pantomime of tool use, actual tool use and imitation of meaningless hand and finger postures were examined in 50 consecutive left-handed subjects with unilateral hemisphere lesions. There were three aphasic patients with pervasive apraxia caused by left-sided lesions. As the dominant hand is controlled by the right hemisphere, they constitute dissociations of apraxia from handedness. Conversely there were also three patients with pervasive apraxia caused by right brain lesions without aphasia. They constitute dissociations of apraxia from aphasia. Across the whole group of patients dissociations from handedness and from aphasia were observed for all manifestations of apraxia, but their frequency depended on the type of apraxia. Defective pantomime and defective tool use occurred rarely without aphasia, whereas defective imitation of hand, but not finger, postures was more frequent after right than left brain damage. The higher incidence of defective imitation of hand postures in right brain damage was mainly due to patients who had also hemi-neglect. This interaction alerts to the possibility that the association of right hemisphere damage with apraxia has to do with spatial aptitudes of the right hemisphere rather than with its control of the dominant left hand. Comparison with data from right-handed patients showed no differences between the severity of apraxia for imitation of hand or finger postures, but impairment on pantomime of tool use was milder in apraxic left-handers than in apraxic right-handers. This alleviation of the severity of apraxia corresponded with a similar alleviation of the severity of aphasia as

  18. Connecting Dirac and Majorana neutrino mass matrices in the minimal left-right symmetric model.

    PubMed

    Nemevšek, Miha; Senjanović, Goran; Tello, Vladimir

    2013-04-12

    Probing the origin of neutrino mass by disentangling the seesaw mechanism is one of the central issues of particle physics. We address it in the minimal left-right symmetric model and show how the knowledge of light and heavy neutrino masses and mixings suffices to determine their Dirac Yukawa couplings. This in turn allows one to make predictions for a number of high and low energy phenomena, such as decays of heavy neutrinos, neutrinoless double beta decay, electric dipole moments of charged leptons, and neutrino transition moments. We also discuss a way of reconstructing the neutrino Dirac Yukawa couplings at colliders such as the LHC.

  19. Silicon Carbide Emitter Turn-Off Thyristor

    DOE PAGES

    Wang, Jun; Wang, Gangyao; Li, Jun; ...

    2008-01-01

    A novel MOS-conmore » trolled SiC thyristor device, the SiC emitter turn-off thyristor (ETO) is a promising technology for future high-voltage switching applications because it integrates the excellent current conduction capability of a SiC thyristor with a simple MOS-control interface. Through unity-gain turn-off, the SiC ETO also achieves excellent Safe Operation Area (SOA) and faster switching speeds than silicon ETOs. The world's first 4.5-kV SiC ETO prototype shows a forward voltage drop of 4.26 V at 26.5  A / cm 2 current density at room and elevated temperatures. Tested in an inductive circuit with a 2.5 kV DC link voltage and a 9.56-A load current, the SiC ETO shows a fast turn-off time of 1.63 microseconds and a low 9.88 mJ turn-off energy. The low switching loss indicates that the SiC ETO could operate at about 4 kHz if 100  W / cm 2 conduction and the 100  W / cm 2 turn-off losses can be removed by the thermal management system. This frequency capability is about 4 times higher than 4.5-kV-class silicon power devices. The preliminary demonstration shows that the SiC ETO is a promising candidate for high-frequency, high-voltage power conversion applications, and additional developments to optimize the device for higher voltage (>5 kV) and higher frequency (10 kHz) are needed.« less

  20. A large left ventricular thrombus.

    PubMed

    Patanè, Salvatore; Marte, Filippo

    2009-06-26

    The discovery of a left ventricular mass obliges the clinician to perform a differential diagnosis including tumour or lipoma versus thrombus and its assessment presents important clinical implications. Dilated cardiomyopathy has been associated with left ventricular thrombosis which leads to substantial morbidity and mortality as a site for peripheral emboli. There are some studies on patients with dilated cardiomyopathy showing altered hemostasis and platelet behavior despite sinus rhythm. An increased incidence of thromboembolism is also well recognized in patients with left ventricular systolic dysfunction complicating history of myocardial infarction. Clinical dilemmas in treating left ventricular thrombus have been described too. We present a case of a large mobile left ventricular thrombus in a 71-year-old Italian man with dilated cardiomyopathy and history of myocardial infarction.

  1. How many hydrogen-bonded α-turns are possible?

    PubMed

    Schreiber, Anette; Schramm, Peter; Hofmann, Hans-Jörg

    2011-06-01

    The formation of α-turns is a possibility to reverse the direction of peptide sequences via five amino acids. In this paper, a systematic conformational analysis was performed to find the possible isolated α-turns with a hydrogen bond between the first and fifth amino acid employing the methods of ab initio MO theory in vacuum (HF/6-31G*, B3LYP/6-311 + G*) and in solution (CPCM/HF/6-31G*). Only few α-turn structures with glycine and alanine backbones fulfill the geometry criteria for the i←(i + 4) hydrogen bond satisfactorily. The most stable representatives agree with structures found in the Protein Data Bank. There is a general tendency to form additional hydrogen bonds for smaller pseudocycles corresponding to β- and γ-turns with better hydrogen bond geometries. Sometimes, this competition weakens or even destroys the i←(i + 4) hydrogen bond leading to very stable double β-turn structures. This is also the reason why an "ideal" α-turn with three central amino acids having the perfect backbone angle values of an α-helix could not be localized. There are numerous hints for stable α-turns with a distance between the C(α)-atoms of the first and fifth amino acid smaller than 6-7 Å, but without an i←(i + 4) hydrogen bond.

  2. Recent developments in turning hardened steels - A review

    NASA Astrophysics Data System (ADS)

    Sivaraman, V.; Prakash, S.

    2017-05-01

    Hard materials ranging from HRC 45 - 68 such as hardened AISI H13, AISI 4340, AISI 52100, D2 STL, D3 STEEL Steel etc., need super hard tool materials to machine. Turning of these hard materials is termed as hard turning. Hard turning makes possible direct machining of the hard materials and also eliminates the lubricant requirement and thus favoring dry machining. Hard turning is a finish turning process and hence conventional grinding is not required. Development of the new advanced super hard tool materials such as ceramic inserts, Cubic Boron Nitride, Polycrystalline Cubic Boron Nitride etc. enabled the turning of these materials. PVD and CVD methods of coating have made easier the production of single and multi layered coated tool inserts. Coatings of TiN, TiAlN, TiC, Al2O3, AlCrN over cemented carbide inserts has lead to the machining of difficult to machine materials. Advancement in the process of hard machining paved way for better surface finish, long tool life, reduced tool wear, cutting force and cutting temperatures. Micro and Nano coated carbide inserts, nanocomposite coated PCBN inserts, micro and nano CBN coated carbide inserts and similar developments have made machining of hardened steels much easier and economical. In this paper, broad literature review on turning of hardened steels including optimizing process parameters, cooling requirements, different tool materials etc., are done.

  3. Spinal Projection Neurons Control Turning Behaviors in Zebrafish

    PubMed Central

    Huang, Kuo-Hua; Ahrens, Misha B.; Dunn, Timothy W.; Engert, Florian

    2013-01-01

    Summary Discrete populations of brainstem spinal projection neurons (SPNs) have been shown to exhibit behavior-specific responses during locomotion [1–9], suggesting that separate descending pathways, each dedicated to a specific behavior, control locomotion. In an alternative model, a large variety of motor outputs could be generated from different combinations of a small number of basic motor pathways. We examined this possibility by studying the precise role of ventromedially located hindbrain SPNs (vSPNs) in generating turning behaviors. We found that unilateral laser ablation of vSPNs reduces the tail deflection and cycle period specifically during the first undulation cycle of a swim bout, whereas later tail movements are unaffected. This holds true during phototaxic [10], optomotor [11], dark-flash-induced [12], and spontaneous turns [13], suggesting a universal role of these neurons in controlling turning behaviors. Importantly, we found that the ablation not only abolishes turns but also results in a dramatic increase in the number of forward swims, suggesting that these neurons transform forward swims into turns by introducing turning kinematics into a basic motor pattern of symmetric tail undulations. Finally, we show that vSPN activity is direction specific and graded by turning angle. Together, these results provide a clear example of how a specific motor pattern can be transformed into different behavioral events by the graded activation of a small set of SPNs. PMID:23910662

  4. Giant and thrombosed left ventricular aneurysm

    PubMed Central

    de Agustin, Jose Alberto; de Diego, Jose Juan Gomez; Marcos-Alberca, Pedro; Rodrigo, Jose Luis; Almeria, Carlos; Mahia, Patricia; Luaces, Maria; Garcia-Fernandez, Miguel Angel; Macaya, Carlos; de Isla, Leopoldo Perez

    2015-01-01

    Left ventricular aneurysms are a frequent complication of acute extensive myocardial infarction and are most commonly located at the ventricular apex. A timely diagnosis is vital due to the serious complications that can occur, including heart failure, thromboembolism, or tachyarrhythmias. We report the case of a 78-year-old male with history of previous anterior myocardial infarction and currently under evaluation by chronic heart failure. Transthoracic echocardiogram revealed a huge thrombosed and calcified anteroapical left ventricular aneurysm. Coronary angiography demonstrated that the left anterior descending artery was chronically occluded, and revealed a big and spherical mass with calcified borders in the left hemithorax. Left ventriculogram confirmed that this spherical mass was a giant calcified left ventricular aneurysm, causing very severe left ventricular systolic dysfunction. The patient underwent cardioverter-defibrillator implantation for primary prevention. PMID:26225205

  5. The evolution of cooperative turn-taking in animal conflict

    PubMed Central

    2011-01-01

    Background A fundamental assumption in animal socio-ecology is that animals compete over limited resources. This view has been challenged by the finding that individuals might cooperatively partition resources by "taking turns". Turn-taking occurs when two individuals coordinate their agonistic behaviour in a way that leads to an alternating pattern in who obtains a resource without engaging in costly fights. Cooperative turn-taking has been largely ignored in models of animal conflict and socio-ecological models that explain the evolution of social behaviours based only on contest and scramble competition. Currently it is unclear whether turn-taking should be included in socio-ecological models because the evolution of turn-taking is not well understood. In particular, it is unknown whether turn-taking can evolve when fighting costs and assessment of fighting abilities are not fixed but emerge from evolved within-fight behaviour. We address this problem with an evolutionary agent-based model. Results We found that turn-taking evolves for small resource values, alongside a contest strategy that leads to stable dominance relationships. Turn-taking leads to egalitarian societies with unclear dominance relationships and non-linear dominance hierarchies. Evolutionary stability of turn-taking emerged despite strength differences among individuals and the possibility to evolve within-fight behaviour that allows good assessment of fighting abilities. Evolutionary stability emerged from frequency-dependent effects on fitness, which are modulated by feedbacks between the evolution of within-fight behaviour and the evolution of higher-level conflict strategies. Conclusions Our results reveal the impact of feedbacks between the evolution of within-fight behaviour and the evolution of higher-level conflict strategies, such as turn-taking. Similar feedbacks might be important for the evolution of other conflict strategies such as winner-loser effects or coalitions. However, we

  6. The evolution of cooperative turn-taking in animal conflict.

    PubMed

    Franz, Mathias; van der Post, Daniel; Schülke, Oliver; Ostner, Julia

    2011-11-03

    A fundamental assumption in animal socio-ecology is that animals compete over limited resources. This view has been challenged by the finding that individuals might cooperatively partition resources by "taking turns". Turn-taking occurs when two individuals coordinate their agonistic behaviour in a way that leads to an alternating pattern in who obtains a resource without engaging in costly fights. Cooperative turn-taking has been largely ignored in models of animal conflict and socio-ecological models that explain the evolution of social behaviours based only on contest and scramble competition. Currently it is unclear whether turn-taking should be included in socio-ecological models because the evolution of turn-taking is not well understood. In particular, it is unknown whether turn-taking can evolve when fighting costs and assessment of fighting abilities are not fixed but emerge from evolved within-fight behaviour. We address this problem with an evolutionary agent-based model. We found that turn-taking evolves for small resource values, alongside a contest strategy that leads to stable dominance relationships. Turn-taking leads to egalitarian societies with unclear dominance relationships and non-linear dominance hierarchies. Evolutionary stability of turn-taking emerged despite strength differences among individuals and the possibility to evolve within-fight behaviour that allows good assessment of fighting abilities. Evolutionary stability emerged from frequency-dependent effects on fitness, which are modulated by feedbacks between the evolution of within-fight behaviour and the evolution of higher-level conflict strategies. Our results reveal the impact of feedbacks between the evolution of within-fight behaviour and the evolution of higher-level conflict strategies, such as turn-taking. Similar feedbacks might be important for the evolution of other conflict strategies such as winner-loser effects or coalitions. However, we are not aware of any study that

  7. Bank-to-turn control technology survey for homing missiles

    NASA Technical Reports Server (NTRS)

    Riedel, F. W.

    1980-01-01

    The potential advantages of bank-to-turn control are summarized. Recent and current programs actively investigating bank-to-turn steering are reviewed and critical technology areas concerned with bank-to-turn control are assessed.

  8. 0-6810 : guidelines for applying right-turn slip lanes.

    DOT National Transportation Integrated Search

    2014-10-01

    Rightturn slip lanes are advantageous to : motorists because they reduce delays by : separating right-turning traffic from adjacent : lanes and accommodating higherspeed right : turns. The right-turn slip lane channelizing : island may also pro...

  9. Left ventricular filling under elevated left atrial pressure

    NASA Astrophysics Data System (ADS)

    Gaddam, Manikantam; Samaee, Milad; Santhanakrishnan, Arvind

    2017-11-01

    Left atrial pressure (LAP) is elevated in diastolic dysfunction, where left ventricular (LV) filling is impaired due to increase in ventricular stiffness. The impact of increasing LAP and LV stiffness on intraventricular filling hemodynamics remains unclear. We conducted particle image velocimetry and hemodynamics measurements in a left heart simulator (LHS) under increasing LAP and LV stiffness at a heart rate of 70 bpm. The LHS consisted of a flexible-walled LV physical model fitted within a fluid-filled chamber. LV wall motion was generated by a piston pump that imparted pressure fluctuations in the chamber. Resistance and compliance elements in the flow loop were adjusted to obtain bulk physiological hemodynamics in the least stiff LV model. Two LV models of increasing stiffness were subsequently tested under unchanged loop settings. LAP was varied between 5-20 mm Hg for each LV model, by adjusting fluid level in a reservoir upstream of the LV. For constant LV stiffness, increasing LAP lowered cardiac output (CO), while ejection fraction (EF) and E/A ratio were increased. For constant LAP, increasing LV stiffness lowered CO and EF, and increased E/A ratio. The implications of these altered hemodynamics on intraventricular filling vortex characteristics will be presented.

  10. Left-handed Children in Singapore.

    ERIC Educational Resources Information Center

    Gan, Linda

    1998-01-01

    Used teacher questionnaires to examine incidence of left-handedness in nearly 2,800 Singaporean children, racial differences in this left-handed population, and educational provisions in preschool and primary school. Findings indicated that 7.5% of preschoolers and 6.3% of primary children were left-handed, with a higher proportion being Chinese…

  11. Kinematic properties of the helicopter in coordinated turns

    NASA Technical Reports Server (NTRS)

    Chen, R. T. N.; Jeske, J. A.

    1981-01-01

    A study on the kinematic relationship of the variables of helicopter motion in steady, coordinated turns involving inherent sideslip is described. A set of exact kinematic equations which govern a steady coordinated helical turn about an Earth referenced vertical axis is developed. A precise definition for the load factor parameter that best characterizes a coordinated turn is proposed. Formulas are developed which relate the aircraft angular rates and pitch and roll attitudes to the turn parameters, angle of attack, and inherent sideslip. A steep, coordinated helical turn at extreme angles of attack with inherent sideslip is of primary interest. The bank angle of the aircraft can differ markedly from the tilt angle of the normal load factor. The normal load factor can also differ substantially from the accelerometer reading along the vertical body axis of the aircraft. Sideslip has a strong influence on the pitch attitude and roll rate of the helicopter. Pitch rate is independent of angle of attack in a coordinated turn and in the absence of sideslip, angular rates about the stability axes are independent of the aerodynamic characteristics of the aircraft.

  12. Effect of left ventricular diastolic dysfunction on left atrial appendage function and thrombotic potential in nonvalvular atrial fibrillation.

    PubMed

    Demirçelik, Muhammed Bora; Çetin, Mustafa; Çiçekcioğlu, Hülya; Uçar, Özgül; Duran, Mustafa

    2014-05-01

    We aimed to investigate effects of left ventricular diastolic dysfunction on left atrial appendage functions, spontaneous echo contrast and thrombus formation in patients with nonvalvular atrial fibrillation. In 58 patients with chronic nonvalvular atrial fibrilation and preserved left ventricular systolic function, left atrial appendage functions, left atrial spontaneous echo contrast grading and left ventricular diastolic functions were evaluated using transthoracic and transoesophageal echocardiogram. Patients divided in two groups: Group D (n=30): Patients with diastolic dysfunction, Group N (n=28): Patients without diastolic dysfunction. Categorical variables in two groups were evaluated with Pearson's chi-square or Fisher's exact test. The significance of the lineer correlation between the degree of spontaneous echo contrast (SEC) and clinical measurements was evaluated with Spearman's correlation analysis. Peak pulmonary vein D velocity of the Group D was significantly higher than the Group N (p=0.006). However, left atrial appendage emptying velocity, left atrial appendage lateral wall velocity, peak pulmonary vein S, pulmonary vein S/D ratio were found to be significantly lower in Group D (p=0.028, p<0.001, p<0.001; p<0.001). Statistically significant negative correlation was found between SEC in left atrium and left atrial appendage emptying, filling, pulmonary vein S/D levels and lateral wall velocities respectively (r=-0.438, r=-0.328, r=-0.233, r=-0.447). Left atrial appendage emptying, filling, pulmonary vein S/D levels and lateral wall velocities were significantly lower in SEC 2-3-4 than SEC 1 (p=0.003, p=0.029, p<0.001, p=0.002). In patients with nonvalvular atrial fibrillation and preserved left ventricular ejection fraction, left atrial appendage functions are decreased in patients with left ventricular diastolic dysfunction. Left ventricular diastolic dysfunction may constitute a potential risk for formation of thrombus and stroke.

  13. Prosody as an interactional resource: turn-projection and overlap.

    PubMed

    Wells, B; Macfarlane, S

    1998-01-01

    One aim of current research into talk-in-interaction is to identify the resources that enable recipients to monitor the course of a turn in progress in order to project its upcoming completion. This issue is addressed through analysis of instances of overlapping talk, focusing on their design--that is, their particular prosodic and other linguistic characteristics; their placement--in other words, where precisely they occur in relation to the turn being overlapped; and the subsequent behavior of the coparticipants. Phonetic analysis is combined with interactional techniques developed within Conversation Analysis, to warrant the relevance of categories by reference to the behavior of the participants themselves. As French and Local (1983) found, for an incoming to be treated as turn-competitive, it has to be designed with relatively high pitch and loud volume. These turn-competitive incomings are positioned within the turn in progress, and before the final major accent. By contrast, overlapping incomings positioned after the major accent are not designed as or treated as turn-competitive. On the basis of this analysis, we can define transition relevance place (TRP) as the space between the TRP-projecting accent of the current turn and the onset of the next turn. TRP-projecting accents are identifiable on independent grounds, being phonetically distinct from non-TRP-projecting accents. They thus provide a robust resource for participants to monitor the upcoming completion of the turn.

  14. Turning in the Testbed

    NASA Image and Video Library

    2004-01-13

    This image, taken in the JPL In-Situ Instruments Laboratory or Testbed, shows the view from the front hazard avoidance cameras on the Mars Exploration Rover Spirit after the rover has backed up and turned 45 degrees counterclockwise.

  15. Misplacement of left-sided double-lumen tubes into the right mainstem bronchus: incidence, risk factors and blind repositioning techniques.

    PubMed

    Seo, Jeong-Hwa; Bae, Jun-Yeol; Kim, Hyun Joo; Hong, Deok Man; Jeon, Yunseok; Bahk, Jae-Hyon

    2015-10-28

    Double-lumen endobronchial tubes (DLTs) are commonly advanced into the mainstem bronchus either blindly or by fiberoptic bronchoscopic guidance. However, blind advancement may result in misplacement of left-sided DLTs into the right bronchus. Therefore, incidence, risk factors, and blind repositioning techniques for right bronchial misplacement of left-sided DLTs were investigated. This was an observational cohort study performed on the data depository consecutively collected from patients who underwent intubation of left-sided DLTs for 2 years. Patients' clinical and anatomical characteristics were analyzed to investigate risk factors for DLT misplacements with logistic regression analysis. Moreover, when DLTs were misplaced into the right bronchus, the bronchial tube was withdrawn into the trachea and blindly readvanced without rotation, or with 90° or 180° counterclockwise rotation while the patient's head was turned right. DLTs were inadvertently advanced into the right bronchus in 48 of 1135 (4.2 %) patients. DLT misplacements occurred more frequently in females, in patients of short stature or with narrow trachea and bronchi, and when small-sized DLTs were used. All of these factors were significantly inter-correlated each other (P < 0.001). In 40 of the 48 (83.3 %) patients, blind repositioning was successful. Smaller left-sided DLTs were more frequently misplaced into the right mainstem bronchus than larger DLTs. Moreover, we were usually able to reposition the misplaced DLTs into the left bronchus by using the blind techniques. ClinicalTrials.gov Identifier: NCT01371773.

  16. Spinal projection neurons control turning behaviors in zebrafish.

    PubMed

    Huang, Kuo-Hua; Ahrens, Misha B; Dunn, Timothy W; Engert, Florian

    2013-08-19

    Discrete populations of brainstem spinal projection neurons (SPNs) have been shown to exhibit behavior-specific responses during locomotion [1-9], suggesting that separate descending pathways, each dedicated to a specific behavior, control locomotion. In an alternative model, a large variety of motor outputs could be generated from different combinations of a small number of basic motor pathways. We examined this possibility by studying the precise role of ventromedially located hindbrain SPNs (vSPNs) in generating turning behaviors. We found that unilateral laser ablation of vSPNs reduces the tail deflection and cycle period specifically during the first undulation cycle of a swim bout, whereas later tail movements are unaffected. This holds true during phototaxic [10], optomotor [11], dark-flash-induced [12], and spontaneous turns [13], suggesting a universal role of these neurons in controlling turning behaviors. Importantly, we found that the ablation not only abolishes turns but also results in a dramatic increase in the number of forward swims, suggesting that these neurons transform forward swims into turns by introducing turning kinematics into a basic motor pattern of symmetric tail undulations. Finally, we show that vSPN activity is direction specific and graded by turning angle. Together, these results provide a clear example of how a specific motor pattern can be transformed into different behavioral events by the graded activation of a small set of SPNs. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

  17. Science in the Making: Right Hand, Left Hand. III: Estimating historical rates of left-handedness.

    PubMed

    McManus, I C; Moore, James; Freegard, Matthew; Rawles, Richard

    2010-01-01

    The BBC television programme Right Hand, Left Hand, broadcast in August 1953, used a postal questionnaire to ask viewers about their handedness. Respondents were born between 1864 and 1948, and in principle therefore the study provides information on rates of left-handedness in those born in the nineteenth century, a group for which few data are otherwise available. A total of 6,549 responses were received, with an overall rate of left-handedness of 15.2%, which is substantially above that expected for a cohort born in the nineteenth and early twentieth centuries. Left-handers are likely to respond preferentially to surveys about handedness, and the extent of over-response can be estimated in modern control data obtained from a handedness website, from the 1953 BBC data, and from Crichton-Browne's 1907 survey, in which there was also a response bias. Response bias appears to have been growing, being relatively greater in the most modern studies. In the 1953 data there is also evidence that left-handers were more common among later rather than early responders, suggesting that left-handers may have been specifically recruited into the study, perhaps by other left-handers who had responded earlier. In the present study the estimated rate of bias was used to correct the nineteenth-century BBC data, which was then combined with other available data as a mixture of two constrained Weibull functions, to obtain an overall estimate of handedness rates in the nineteenth century. The best estimates are that left-handedness was at its nadir of about 3% for those born between about 1880 and 1900. Extrapolating backwards, the rate of left-handedness in the eighteenth century was probably about 10%, with the decline beginning in about 1780, and reaching around 7% in about 1830, although inevitably there are many uncertainties in those estimates. What does seem indisputable is that rates of left-handedness fell during most of the nineteenth century, only subsequently to rise in

  18. Left inferior frontal cortex and syntax: function, structure and behaviour in patients with left hemisphere damage

    PubMed Central

    Marslen-Wilson, William D.; Randall, Billi; Wright, Paul; Devereux, Barry J.; Zhuang, Jie; Papoutsi, Marina; Stamatakis, Emmanuel A.

    2011-01-01

    For the past 150 years, neurobiological models of language have debated the role of key brain regions in language function. One consistently debated set of issues concern the role of the left inferior frontal gyrus in syntactic processing. Here we combine measures of functional activity, grey matter integrity and performance in patients with left hemisphere damage and healthy participants to ask whether the left inferior frontal gyrus is essential for syntactic processing. In a functional neuroimaging study, participants listened to spoken sentences that either contained a syntactically ambiguous or matched unambiguous phrase. Behavioural data on three tests of syntactic processing were subsequently collected. In controls, syntactic processing co-activated left hemisphere Brodmann areas 45/47 and posterior middle temporal gyrus. Activity in a left parietal cluster was sensitive to working memory demands in both patients and controls. Exploiting the variability in lesion location and performance in the patients, voxel-based correlational analyses showed that tissue integrity and neural activity—primarily in left Brodmann area 45 and posterior middle temporal gyrus—were correlated with preserved syntactic performance, but unlike the controls, patients were insensitive to syntactic preferences, reflecting their syntactic deficit. These results argue for the essential contribution of the left inferior frontal gyrus in syntactic analysis and highlight the functional relationship between left Brodmann area 45 and the left posterior middle temporal gyrus, suggesting that when this relationship breaks down, through damage to either region or to the connections between them, syntactic processing is impaired. On this view, the left inferior frontal gyrus may not itself be specialized for syntactic processing, but plays an essential role in the neural network that carries out syntactic computations. PMID:21278407

  19. Stepping in Place While Voluntarily Turning Around Produces a Long-Lasting Posteffect Consisting in Inadvertent Turning While Stepping Eyes Closed

    PubMed Central

    2016-01-01

    Training subjects to step in place on a rotating platform while maintaining a fixed body orientation in space produces a posteffect consisting in inadvertent turning around while stepping in place eyes closed (podokinetic after-rotation, PKAR). We tested the hypothesis that voluntary turning around while stepping in place also produces a posteffect similar to PKAR. Sixteen subjects performed 12 min of voluntary turning while stepping around their vertical axis eyes closed and 12 min of stepping in place eyes open on the center of a platform rotating at 60°/s (pretests). Then, subjects continued stepping in place eyes closed for at least 10 min (posteffect). We recorded the positions of markers fixed to head, shoulder, and feet. The posteffect of voluntary turning shared all features of PKAR. Time decay of angular velocity, stepping cadence, head acceleration, and ratio of angular velocity after to angular velocity before were similar between both protocols. Both postrotations took place inadvertently. The posteffects are possibly dependent on the repeated voluntary contraction of leg and foot intrarotating pelvic muscles that rotate the trunk over the stance foot, a synergy common to both protocols. We propose that stepping in place and voluntary turning can be a scheme ancillary to the rotating platform for training body segment coordination in patients with impairment of turning synergies of various origin. PMID:27635264

  20. Agraphia of the left hand with dysfunction of the left superior parietal region without callosal lesions.

    PubMed

    Kinno, Ryuta; Ohashi, Hideaki; Mori, Yukiko; Shiromaru, Azusa; Ono, Kenjiro

    2018-03-01

    A 28-year-old right-handed man noticed weakness in his legs, three days after an ephedrine overdose. Initial brain magnetic resonance imaging showed lesions in the parietal regions bilaterally. Computed tomography angiography showed segmental and multifocal vasoconstriction of the cerebral arteries. After treatment, clinical and radiological findings resolved, suggesting the patient had reversible cerebral vasoconstriction syndrome with posterior reversible encephalopathy syndrome. However, he had residual agraphia of the left hand. Language testing revealed no difficulties in oral expression, auditory comprehension, understanding of written language, or writing with the right hand. I-123 iodoamphetamine single-photon emission computed tomography showed residual dysfunction in the left superior parietal lobule. There were no apparent signs of other disconnection syndromes or neuroimaging abnormalities in the corpus callosum. We diagnosed left-hand agraphia due to left parietal dysfunction. Our case suggests that left superior parietal dysfunction without callosal lesions is a possible cause of left-hand agraphia. Neural mechanisms for writing with the right or left hand may be separable at the cortical level.

  1. Steady properly-banked turns of turbojet-propelled airplanes

    NASA Technical Reports Server (NTRS)

    Miele, Angelo

    1955-01-01

    The problem of a jet-propelled airplane held in a steady turn is treated both in the very general case and also in the particular case when the polar curve can be approximated by a parabola. Once the general solution has been obtained, some typical maneuvers are next studied such as, the turn of maximum bank, of maximum angular velocity, and of minimum radius of curvature. After a brief comparison is made between the turning characteristics of conventional airplanes and jet airplanes, and after the effect of compressibility upon the turn is examined, the effects of the salient aerodynamic and structural parameters upon the behavior of the plane in curvilinear flight are summarized in the conclusions.

  2. Left ventricular assist device implantation via left thoracotomy: alternative to repeat sternotomy.

    PubMed

    Pierson, Richard N; Howser, Renee; Donaldson, Terri; Merrill, Walter H; Dignan, Rebecca J; Drinkwater, Davis C; Christian, Karla G; Butler, Javed; Chomsky, Don; Wilson, John R; Clark, Rick; Davis, Stacy F

    2002-03-01

    Repeat sternotomy for left ventricular assist device insertion may result in injury to the right heart or patent coronary grafts, complicating intraoperative and postoperative management. In 4 critically ill patients, left thoracotomy was used as an alternative to repeat sternotomy. Anastomosis of the outflow conduit to the descending thoracic aorta provided satisfactory hemodynamic support.

  3. Left Superior Vena Cava Draining Into Left Atrium in Tetralogy of Fallot-Four Cases of a Rare Association.

    PubMed

    Ramman, Tarun Raina; Dutta, Nilanjan; Chowdhuri, Kuntal Roy; Agrawal, Sunny; Girotra, Sumir; Azad, Sushil; Radhakrishnan, Sitaraman; Iyer, Parvathi Unninayar; Iyer, Krishna Subramony

    2018-01-01

    Persistent left superior vena cava is a common congenital anomaly of the thoracic venous system. Left superior vena cava draining into left atrium is a malformation of sinus venosus and caval system. The anomaly may be a cause of unexplained hypoxia even in adults. It may give rise to various diagnostic and technical challenges during cardiac catheterization and open-heart surgery. It is often detected serendipitously during diagnostic workup. Isolated left superior vena cava opening into left atrium is very commonly associated with other congenital heart defects. But tetralogy of Fallot is very rarely associated with persistent left superior vena cava which drains into left atrium. We report four such cases who underwent surgical correction successfully.

  4. Consciousness wanted, attention found: Reasons for the advantage of the left visual field in identifying T2 among rapidly presented series.

    PubMed

    Verleger, Rolf; Śmigasiewicz, Kamila

    2015-09-01

    Everyday experience suggests that people are equally aware of events in both hemi-fields. However, when two streams of stimuli are rapidly presented left and right containing two targets, the second target is better identified in the left than in the right visual field. This might be considered evidence for a right-hemisphere advantage in generating conscious percepts. However, this putative asymmetry of conscious perception cannot be measured independently of participants' access to their conscious percepts, and there is actually evidence from split-brain patients for the reverse, left-hemisphere advantage in having access to conscious percepts. Several other topics were studied in search of the responsible mechanism, among others: Mutual inhibition of hemispheres, cooperation of hemispheres in perceiving midline stimuli, and asymmetries in processing various perceptual inputs. Directing attention by salient cues turned out to be one of the few mechanisms capable of modifying the left visual-field advantage in this paradigm. Thus, this left visual-field advantage is best explained by the notion of a right-hemisphere advantage in directing attention to salient events. Dovetailing with the pathological asymmetries of attention after right-hemisphere lesions and with asymmetries of brain activation when healthy participants shift their attention, the present results extend that body of evidence by demonstrating unusually large and reliable behavioral asymmetries for attention-directing processes in healthy participants. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Abnormal turning behaviour, GABAergic inhibition and the degeneration of astrocytes in ovine Tribulus terrestris motor neuron disease.

    PubMed

    Bourke, C A

    2006-01-01

    To observe the clinical signs of sheep affected by Tribulus terrestris motor neuron disease, to ascertain their response to striatal dopamine reducing drugs, and to examine their brains and spinal cords for microscopic changes. Twenty-eight sheep displaying well developed clinical signs of the disorder were observed. Twenty-two of these and 22 normal sheep were then randomly allocated to three groups and treated with diazepam, chlorpromazine, or xylazine. The time that it took an animal to return to a standing position following drug administration was recorded. The brain and complete spinal cord were removed from each of the other six affected sheep and fixed in formalin. Brains were sectioned throughout at 5 mm intervals and spinal cords at 10 mm intervals. All tissues were paraffin embedded and examined by light microscopy. A few samples were examined by electron microscopy. Clinical signs included postural asymmetry with a right:left body-side dominance within the group of 50:50, unequal flaccid paresis in the pelvic limbs, extensor muscle atrophy and adduction of the weaker pelvic limb, and concurrent abduction of the stronger. Forward motion followed either a fixed left or right hand curved trajectory, the sheep no longer being able to choose which. Twelve animals intermittently displayed rotational behaviour that involved loss of postural balance without locomotor activation. The administration of diazepam, chlorpromazine, or xylazine caused limb paresis and sedation, with affected sheep being slower than normal sheep by factors of 8, 3 and 2 respectively, to return to a standing position. There were scattered areas of mild Wallerian degeneration throughout the spinal cord, and in both the brain and the cord there were small numbers of degenerate astrocytes containing novel cytoplasmic pigment granules. Affected sheep had a dysfunction in the control of directional change and this provides a new insight into the normal mechanism for 'turning' in quadrupeds

  6. 14 CFR 417.209 - Malfunction turn analysis.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... nozzle burn-through. For each cause of a malfunction turn, the analysis must establish the launch vehicle... the launch vehicle's turning capability in the event of a malfunction during flight. A malfunction... launch vehicle is capable. (4) The time, as a single value or a probability time distribution, when each...

  7. 14 CFR 417.209 - Malfunction turn analysis.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... nozzle burn-through. For each cause of a malfunction turn, the analysis must establish the launch vehicle... the launch vehicle's turning capability in the event of a malfunction during flight. A malfunction... launch vehicle is capable. (4) The time, as a single value or a probability time distribution, when each...

  8. Exceptional running and turning performance in a mite.

    PubMed

    Rubin, Samuel; Young, Maria Ho-Yan; Wright, Jonathan C; Whitaker, Dwight L; Ahn, Anna N

    2016-03-01

    The Southern California endemic mite Paratarsotomus macropalpis was filmed in the field on a concrete substrate and in the lab to analyze stride frequency, gait and running speed under different temperature conditions and during turning. At ground temperatures ranging from 45 to 60 °C, mites ran at a mean relative speed of 192.4 ± 2.1 body lengths (BL) s(-1), exceeding the highest previously documented value for a land animal by 12.5%. Stride frequencies were also exceptionally high (up to 135 Hz), and increased with substrate temperature. Juveniles exhibited higher relative speeds than adults and possess proportionally longer legs, which allow for greater relative stride lengths. Although mites accelerated and decelerated rapidly during straight running (7.2 ± 1.2 and -10.1 ± 2.1 m s(-2), respectively), the forces involved were comparable to those found in other animals. Paratarsotomus macropalpis employs an alternating tetrapod gait during steady running. Shallow turns were accomplished by a simple asymmetry in stride length. During tight turns, mites pivoted around the tarsus of the inside third leg (L3), which thus behaved like a grappling hook. Pivot turns were characterized by a 42% decrease in turning radius and a 40% increase in angular velocity compared with non-pivot turns. The joint angle amplitudes of the inner L2 and L3 were negligible during a pivot turn. While exceptional, running speeds in P. macropalpis approximate values predicted from inter-specific scaling relationships. © 2016. Published by The Company of Biologists Ltd.

  9. Predicting β-Turns in Protein Using Kernel Logistic Regression

    PubMed Central

    Elbashir, Murtada Khalafallah; Sheng, Yu; Wang, Jianxin; Wu, FangXiang; Li, Min

    2013-01-01

    A β-turn is a secondary protein structure type that plays a significant role in protein configuration and function. On average 25% of amino acids in protein structures are located in β-turns. It is very important to develope an accurate and efficient method for β-turns prediction. Most of the current successful β-turns prediction methods use support vector machines (SVMs) or neural networks (NNs). The kernel logistic regression (KLR) is a powerful classification technique that has been applied successfully in many classification problems. However, it is often not found in β-turns classification, mainly because it is computationally expensive. In this paper, we used KLR to obtain sparse β-turns prediction in short evolution time. Secondary structure information and position-specific scoring matrices (PSSMs) are utilized as input features. We achieved Q total of 80.7% and MCC of 50% on BT426 dataset. These results show that KLR method with the right algorithm can yield performance equivalent to or even better than NNs and SVMs in β-turns prediction. In addition, KLR yields probabilistic outcome and has a well-defined extension to multiclass case. PMID:23509793

  10. Predicting β-turns in protein using kernel logistic regression.

    PubMed

    Elbashir, Murtada Khalafallah; Sheng, Yu; Wang, Jianxin; Wu, Fangxiang; Li, Min

    2013-01-01

    A β-turn is a secondary protein structure type that plays a significant role in protein configuration and function. On average 25% of amino acids in protein structures are located in β-turns. It is very important to develope an accurate and efficient method for β-turns prediction. Most of the current successful β-turns prediction methods use support vector machines (SVMs) or neural networks (NNs). The kernel logistic regression (KLR) is a powerful classification technique that has been applied successfully in many classification problems. However, it is often not found in β-turns classification, mainly because it is computationally expensive. In this paper, we used KLR to obtain sparse β-turns prediction in short evolution time. Secondary structure information and position-specific scoring matrices (PSSMs) are utilized as input features. We achieved Q total of 80.7% and MCC of 50% on BT426 dataset. These results show that KLR method with the right algorithm can yield performance equivalent to or even better than NNs and SVMs in β-turns prediction. In addition, KLR yields probabilistic outcome and has a well-defined extension to multiclass case.

  11. Cilia in vertebrate left-right patterning.

    PubMed

    Dasgupta, Agnik; Amack, Jeffrey D

    2016-12-19

    Understanding how left-right (LR) asymmetry is generated in vertebrate embryos is an important problem in developmental biology. In humans, a failure to align the left and right sides of cardiovascular and/or gastrointestinal systems often results in birth defects. Evidence from patients and animal models has implicated cilia in the process of left-right patterning. Here, we review the proposed functions for cilia in establishing LR asymmetry, which include creating transient leftward fluid flows in an embryonic 'left-right organizer'. These flows direct asymmetric activation of a conserved Nodal (TGFβ) signalling pathway that guides asymmetric morphogenesis of developing organs. We discuss the leading hypotheses for how cilia-generated asymmetric fluid flows are translated into asymmetric molecular signals. We also discuss emerging mechanisms that control the subcellular positioning of cilia and the cellular architecture of the left-right organizer, both of which are critical for effective cilia function during left-right patterning. Finally, using mosaic cell-labelling and time-lapse imaging in the zebrafish embryo, we provide new evidence that precursor cells maintain their relative positions as they give rise to the ciliated left-right organizer. This suggests the possibility that these cells acquire left-right positional information prior to the appearance of cilia.This article is part of the themed issue 'Provocative questions in left-right asymmetry'. © 2016 The Author(s).

  12. Optical Neasurements Of Diamond-Turned Surfaces

    NASA Astrophysics Data System (ADS)

    Politch, Jacob

    1989-07-01

    We describe here a system for measuring very accurately diamond-turned surfaces. This system is based on heterodyne interfercmetry and measures surface height variations with an accuracy of 4A, and the spatial resolution is 1 micrometer. Fran the measured data we have calculated the statistical properties of the surface - enabling us to identify the spatial frequencies caused by the vibrations of the diamond - turning machine and the measuring machine as well as the frequency of the grid.

  13. Precision lens assembly with alignment turning system

    NASA Astrophysics Data System (ADS)

    Ho, Cheng-Fang; Huang, Chien-Yao; Lin, Yi-Hao; Kuo, Hui-Jean; Kuo, Ching-Hsiang; Hsu, Wei-Yao; Chen, Fong-Zhi

    2017-10-01

    The poker chip assembly with high precision lens barrels is widely applied to ultra-high performance optical system. ITRC applies the poker chip assembly technology to the high numerical aperture objective lenses and lithography projection lenses because of its high efficiency assembly process. In order to achieve high precision lens cell for poker chip assembly, an alignment turning system (ATS) is developed. The ATS includes measurement, alignment and turning modules. The measurement module is equipped with a non-contact displacement sensor (NCDS) and an autocollimator (ACM). The NCDS and ACM are used to measure centration errors of the top and the bottom surface of a lens respectively; then the amount of adjustment of displacement and tilt with respect to the rotational axis of the turning machine for the alignment module can be determined. After measurement, alignment and turning processes on the ATS, the centration error of a lens cell with 200 mm in diameter can be controlled within 10 arcsec. Furthermore, a poker chip assembly lens cell with three sub-cells is demonstrated, each sub-cells are measured and accomplished with alignment and turning processes. The lens assembly test for five times by each three technicians; the average transmission centration error of assembly lens is 12.45 arcsec. The results show that ATS can achieve high assembly efficiency for precision optical systems.

  14. Left Paraduodenal Hernia.

    PubMed

    Martins, Aires; Gonçalves, Álvaro; Almeida, Teresa; Gomes, Rui; Lomba, João; Midões, Alberto

    2018-05-01

    Left paraduodenal hernia is an entrapment of the small bowel into the Landzert fossa, an unusual congenital peritoneal defect behind the descending mesocolon that results from failure of part of the descending mesocolon to fuse with the posterior parietal peritoneum (Doishita et al. in Radiographics, 36(1): 88-106, 2016). This fossa is reported to be present in approximately 2% of autopsy bodies. The authors present a case of a left paraduodenal hernia in a young woman.

  15. Aircraft control forces and EMG activity: comparison of novice and experienced pilots during simulated rolls, loops and turns.

    PubMed

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

    2000-08-01

    Flying an aircraft requires a considerable degree of coordination, particularly during aerobatic activities such as rolls, loops and turns. Only one previous study has examined the magnitude of muscle activity required to fly an aircraft, and that was restricted to takeoff and landing maneuvers. The aim of this study was to examine the phasing of muscle activation and control forces of novice and experienced pilots during more complex simulated flight maneuvers. There were 12 experienced and 9 novice pilots who were tested on an Aermacchi flight simulator while performing a randomized set of rolling, looping, and turning maneuvers. Four different runaway trim settings were used to increase the difficulty of the turns (elevator-up, elevator-down, aileron-left, and aileron-right). Variables recorded included aircraft attitude, pilot applied forces, and electromyographic (EMG) activity. Discriminant function analysis was used to distinguish between novice and experienced pilots. Over all maneuvers, 70% of pilots were correctly classified as novice or experienced. Better levels of classification were achieved when maneuvers were analyzed individually (67-91%), although the maneuvers that required the greatest force application, elevator-up turns, were unable to discriminate between novice and experienced pilots. There were no differences in the phasing of muscle activity between experienced and novice pilots. The only consistent difference in EMG activity between novice and experienced pilots was the reduced EMG activity in the wrist extensors of experienced pilots (p < 0.05). The increased wrist extensor activity of the novice pilots is indicative of a distal control strategy, whereby distal muscles with smaller motor units are used to perform a task that requires precise control. Muscle activity sensors could be used to detect the onset of high G maneuvers prior to any change in aircraft attitude and control G-suit inflation accordingly.

  16. Identifying protein β-turns with vibrational Raman optical activity.

    PubMed

    Weymuth, Thomas; Jacob, Christoph R; Reiher, Markus

    2011-04-18

    β-turns belong to the most important secondary structure elements in proteins. On the basis of density functional calculations, vibrational Raman optical activity signatures of different types of β-turns are established and compared as well as related to other signatures proposed in the literature earlier. Our findings indicate that there are much more characteristic ROA signals of β-turns than have been hitherto suggested. These suggested signatures are, however, found to be valid for the most important type of β-turns. Moreover, we compare the influence of different amino acid side chains on these signatures and investigate the discrimination of β-turns from other secondary structure elements, namely α- and 3(10)-helices. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Structural and sequence features of two residue turns in beta-hairpins.

    PubMed

    Madan, Bharat; Seo, Sung Yong; Lee, Sun-Gu

    2014-09-01

    Beta-turns in beta-hairpins have been implicated as important sites in protein folding. In particular, two residue β-turns, the most abundant connecting elements in beta-hairpins, have been a major target for engineering protein stability and folding. In this study, we attempted to investigate and update the structural and sequence properties of two residue turns in beta-hairpins with a large data set. For this, 3977 beta-turns were extracted from 2394 nonhomologous protein chains and analyzed. First, the distribution, dihedral angles and twists of two residue turn types were determined, and compared with previous data. The trend of turn type occurrence and most structural features of the turn types were similar to previous results, but for the first time Type II turns in beta-hairpins were identified. Second, sequence motifs for the turn types were devised based on amino acid positional potentials of two-residue turns, and their distributions were examined. From this study, we could identify code-like sequence motifs for the two residue beta-turn types. Finally, structural and sequence properties of beta-strands in the beta-hairpins were analyzed, which revealed that the beta-strands showed no specific sequence and structural patterns for turn types. The analytical results in this study are expected to be a reference in the engineering or design of beta-hairpin turn structures and sequences. © 2014 Wiley Periodicals, Inc.

  18. Two cases of left superior vena cava draining directly to a left atrium with a normal coronary sinus.

    PubMed Central

    Wiles, H B

    1991-01-01

    The most common variation in the thoracic systemic venous system is a persistent left superior vena cava draining to a coronary sinus. A rare anomaly is a persistent left superior vena cava connecting directly to the left atrium. In this situation it is believed that the coronary sinus must be absent. This report describes two cases of a persistent left superior vena cava draining to a left atrium with a normal coronary sinus. Images PMID:2015125

  19. Acoustic energy exchange through flow turning

    NASA Astrophysics Data System (ADS)

    Baum, Joseph D.

    1987-01-01

    A numerical investigation of the mechanisms of acoustic energy exchange between the mean and acoustic flow fields in resonance chambers, such as rocket engines, is reported. A noniterative linearized block implicit scheme was used to solve the time-dependent compressible Navier-Stokes equations. Two test cases were investigated: acoustic wave propagation in a tube with a coexisting sheared mean flow (the refraction test) and acoustic wave propagation in a tube where the mean sheared flow was injected into the tube through its lateral boundary (the flow turning study). For flow turning, significant excitation of mean flow energy was observed at two locations: at the edge of the acoustic boundary layer and within a zone adjacent to the acoustic boundary layer extending up to 0.1 radii away from the wall. A weaker streaming effect was observed for the refraction study, and only at the edge of the acoustic boundary layer. The total dissipation for the flow turning test was twice the dissipation for refraction.

  20. Does the timing of parental migration matter for child growth? A life course study on left-behind children in rural China.

    PubMed

    Zhang, Nan; Bécares, Laia; Chandola, Tarani

    2015-09-25

    China's unprecedented internal migration has left 61 million rural children living apart from parents. This study investigates how being left behind is associated with children's growth, by examining children's height and weight trajectories by age, testing the accumulation and critical period life course hypotheses. Data were drawn from five waves of the China Health and Nutrition Survey (CHNS). Multiple cohorts of children under 6 years old from 1997-2009 were examined (N = 2,555). Growth curve models investigated whether height and weight trajectories differ for children who were left behind at different stages of the life course: in early childhood (from ages 0-5 but not afterwards), in later childhood (from ages 6 to 17 only), and in both early and later childhood (from ages 0-5 and from ages 6-17), compared to their peers from intact households. Boys who were left behind at different life stages of childhood differed in height and weight growth compared with boys from intact families. No significant associations were found for girls. As young boys turned into adolescents, those left behind in early childhood tended to have slower height growth and weight gain than their peers from intact households. There was a 2.8 cm difference in the predicted heights of boys who were left behind in early childhood compared to boys from intact households, by the age of 14. Similarly, the difference in weight between the two groups of boys was 5.3 kg by the age of 14. Being left behind during early childhood, as compared to not being left behind, could lead to slower growth rates of height and weight for boys. The life course approach adopted in this study suggests that early childhood is a critical period of children's growth in later life, especially for boys who are left behind. The gender paradox in China, where sons are preferred, but being left behind appears to affect boys more than girls, needs further exploration.

  1. [Memorization of Sequences of Movements of the Right and the Left Hand by Right- and Left-Handers].

    PubMed

    Bobrova, E V; Bogacheva, I N; Lyakhovetskii, V A; Fabinskaja, A A; Fomina, E V

    2015-01-01

    We analyzed the errors of right- and left-handers when performing memorized sequences by the left or the right hand during the task which activates positional coding: after 6-10 times the order of movements changed (the positions remained the same during all task). The task was first performed by one ("initial") hand, and then by another one ("continuing"); there were 2 groups of right-handers and 2 groups of left-handers. It was found that the pattern of errors during the task performance by the initial hand is similar in right- and left-handers both for the dominant and non-dominant hand. The information about the previous positions after changing the order of elements is used in the sequences for subdominant hands and not used in the sequences for dominant ones. After changing the hand, right- and left-handers show different patterns of errors ("non-symmetrical"). Thus, the errors of right- and left-handers are "symmetrical" at the early stages of task performance, while the transfer of this motor skill in right-and left-handers occurs in different ways.

  2. Diamond turning of Si and Ge single crystals

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

    Blake, P.; Scattergood, R.O.

    Single-point diamond turning studies have been completed on Si and Ge crystals. A new process model was developed for diamond turning which is based on a critical depth of cut for plastic flow-to-brittle fracture transitions. This concept, when combined with the actual machining geometry for single-point turning, predicts that {open_quotes}ductile{close_quotes} machining is a combined action of plasticity and fracture. Interrupted cutting experiments also provide a meant to directly measure the critical depth parameter for given machining conditions.

  3. ω-Turn: a novel β-turn mimic in globular proteins stabilized by main-chain to side-chain C−H···O interaction.

    PubMed

    Dhar, Jesmita; Chakrabarti, Pinak; Saini, Harpreet; Raghava, Gajendra Pal Singh; Kishore, Raghuvansh

    2015-02-01

    Mimicry of structural motifs is a common feature in proteins. The 10-membered hydrogen-bonded ring involving the main-chain C − O in a β-turn can be formed using a side-chain carbonyl group leading to Asx-turn. We show that the N − H component of hydrogen bond can be replaced by a C(γ) -H group in the side chain, culminating in a nonconventional C − H···O interaction. Because of its shape this β-turn mimic is designated as ω-turn, which is found to occur ∼ three times per 100 residues. Three residues (i to i + 2) constitute the turn with the C − H···O interaction occurring between the terminal residues, constraining the torsion angles ϕi + 1, ψi + 1, ϕi + 2 and χ'1(i + 2) (using the interacting C(γ) atom). Based on these angles there are two types of ω-turns, each of which can be further divided into two groups. C(β) -branched side-chains, and Met and Gln have high propensities to occur at i + 2; for the last two residues the carbonyl oxygen may participate in an additional interaction involving the S and amino group, respectively. With Cys occupying the i + 1 position, such turns are found in the metal-binding sites. N-linked glycosylation occurs at the consensus pattern Asn-Xaa-Ser/Thr; with Thr at i + 2, the sequence can adopt the secondary structure of a ω-turn, which may be the recognition site for protein modification. Location between two β-strands is the most common occurrence in protein tertiary structure, and being generally exposed ω-turn may constitute the antigenic determinant site. It is a stable scaffold and may be used in protein engineering and peptide design. © 2014 Wiley Periodicals, Inc.

  4. The Left Atrial Appendage Revised

    PubMed Central

    Evora, Paulo Roberto Barbosa; Menardi, Antonio Carlos; Celotto, Andrea Carla; Albuquerque, Agnes Afrodite S.; Chagas, Hannah Miranda Araujo; Rodrigues, Alfredo José

    2017-01-01

    Nonvalvular atrial fibrillation is associated with a 4- to 5-fold strokes increase and may be responsible for 15% to 20% of all strokes in the elderly. In this scenario, the left atrial appendage thrombus would be the associated with 90% of cases. The use of anticoagulants, percutaneous devices, and the left atrial appendage surgical exclusion is still an open discussion. For left atrial appendage procedures, relevant anatomic spatial relationships have to be emphasized, besides the chance of the normal physiological functioning would be eliminated with the proceedings. There are evidences that the left atrial appendage closure during routine cardiac surgery is significantly associated with an increased risk of early postoperative atrial fibrillation. Therefore, the purpose of this review is to focus basic aspects for continuous medical education. In summary, the rationale of this text is to emphasize anatomical and pharmacological aspects involved in the simple surgical exclusion of left atrial appendage under cardiopulmonary bypass. There are several operative techniques, but to conclude this revision it will present one of them based on the discussed basic sciences. PMID:29267615

  5. High voltage and current, gate assisted, turn-off thyristor development

    NASA Technical Reports Server (NTRS)

    Nowalk, T. P.; Brewster, J. B.; Kao, Y. C.

    1972-01-01

    An improved high speed power switch with unique turn-off capability was developed. This gate assisted turn-off thyristor (GATT) was rated 1000 volts and 100 amperes with turn-off times of 2 microseconds. Fifty units were delivered for evaluation. In addition, test circuits designed to relate to the series inverter application were built and demonstrated. In the course of this work it was determined that the basic device design is adequate to meet the static characteristics and dynamic turn-off specification. It was further determined that the turn-on specification is critically dependent on the gate drive circuit due to the distributive nature of the cathode-gate geometry. Future work should emphasize design modifications which reduce the gate current required for fast turn-on, thereby opening the way to higher power (current) devices.

  6. Diamond turning machine controller implementation

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

    Garrard, K.P.; Taylor, L.W.; Knight, B.F.

    The standard controller for a Pnuemo ASG 2500 Diamond Turning Machine, an Allen Bradley 8200, has been replaced with a custom high-performance design. This controller consists of four major components. Axis position feedback information is provided by a Zygo Axiom 2/20 laser interferometer with 0.1 micro-inch resolution. Hardware interface logic couples the computers digital and analog I/O channels to the diamond turning machine`s analog motor controllers, the laser interferometer, and other machine status and control information. It also provides front panel switches for operator override of the computer controller and implement the emergency stop sequence. The remaining two components, themore » control computer hardware and software, are discussed in detail below.« less

  7. [Hyperlexia in an adult patient with lesions in the left medial frontal lobe].

    PubMed

    Suzuki, K; Yamadori, A; Kumabe, T; Endo, K; Fujii, T; Yoshimoto, T

    2000-04-01

    A 69-year-old right-handed woman developed a transcortical motor aphasia with hyperlexia following resection of a glioma in the left medial frontal lobe. Neurological examination revealed grasp reflex in the right hand and underutilization of the right upper extremity. An MRI demonstrated lesions in the left medial frontal lobe including the supplementary motor area and the anterior part of the cingulate gyrus, which extended to the anterior part of the body of corpus callosum. Neuropsychologically she was alert and cooperative. She demonstrated transcortical motor aphasia. Her verbal output began with echolalia. Furthermore hyperlexia was observed in daily activities and during examinations. During conversation she suddenly read words written on objects around her which were totally irrelevant to the talk. When she was walking in the ward with an examiner she read words written on a trash bag that passed by and signboards which indicated a name of a room. Her conversation while walking was intermingled with reading words, which was irrelevant to the conversation. She also read time on analog clocks, which were hung on a wall in a watch store. In a naming task, she read words written on objects first and named them upon repeated question about their names. When an examiner opened a newspaper in front of her without any instructions she began reading until the examiner prohibited it. Then she began reading again when an examiner turned the page, although she remembered that she should not read it aloud. She showed mild ideomotor apraxia of a left hand. Utilization behavior, imitation behavior, hypergraphia, or compulsive use of objects was not observed throughout the course. Hyperlexic tendency is a prominent feature of this patient's language output. Hyperlexia was often reported in children with pervasive developmental disorders including autism. There are only a few reports about hyperlexia in adults and some of them were related to diffuse brain dysfunction

  8. Medium dependent dual turn on/turn off fluorescence sensing for Cu2 + ions using AMI/SDS assemblies

    NASA Astrophysics Data System (ADS)

    Gujar, Varsha B.; Ottoor, Divya

    2017-02-01

    Behavior of Amiloride (AMI) as a metal ion sensor in anionic surfactant assemblies of varying concentrations at different pH is depicted in this work. From a non-sensor fluorophore, AMI has been transformed in to a tunable fluorosensor for Cu2 + ions in various SDS concentrations. At premicellar concentration of SDS, ion-pair complex is expected to be formed between AMI and SDS due to electrostatic interactions between them. However at CMC concentrations of SDS, fluorescence intensity of AMI is greatly enhanced with red shift in emission, due to the incorporation of AMI molecule in the hydrophobic micellar interface. The behavior of metal sensing by AMI-SDS assemblies gives rise to several interesting observations. Micellation of SDS has been greatly enhanced by increasing copper ion concentrations, as these counter ions screens the charge on monomers of SDS which lead to the aggregation at premicellar concentrations only. Concentrations and pH dependent discrete trends of interactions between SDS-AMI and SDS-Cu2 + ions, have given tunable fluorescence responses (fluorescence turn on/turn off) of AMI for added Cu2 + ions. The electrostatic interaction between the metal cations and the anionic surfactants is the driving force for bringing the metal ions near to the vicinity of micelle where AMI resides. Thus, a comprehensive understanding of the mechanism related to the 'turn on-turn off' fluorescence response of AMI with respect to pH and SDS concentration for effective Cu2 + ion sensing is illustrated in this work.

  9. Reconceptualizing Autonomy: A Relational Turn in Bioethics.

    PubMed

    Jennings, Bruce

    2016-05-01

    History's judgment on the success of bioethics will not depend solely on the conceptual creativity and innovation in the field at the level of ethical and political theory, but this intellectual work is not insignificant. One important new development is what I shall refer to as the relational turn in bioethics. This development represents a renewed emphasis on the ideographic approach, which interprets the meaning of right and wrong in human actions as they are inscribed in social and cultural practices and in structures of lived meaning and interdependence; in an ideographic approach, the task of bioethics is to bring practice into theory, not the other way around. The relational turn in bioethics may profoundly affect the critical questions that the field asks and the ethical guidance it offers society, politics, and policy. The relational turn provides a way of correcting the excessive atomism of many individualistic perspectives that have been, and continue to be, influential in bioethics. Nonetheless, I would argue that most of the work reflecting the relational turn remains distinctively liberal in its respect for the ethical significance of the human individual. It moves away from individualism, but not from the value of individuality.In this review essay, I shall focus on how the relational turn has manifested itself in work on core concepts in bioethics, especially liberty and autonomy. Following a general review, I conclude with a brief consideration of two important recent books in this area: Jennifer Nedelsky's Law's Relations and Rachel Haliburton's Autonomy and the Situated Self. © 2016 The Hastings Center.

  10. Simulation of turn-by-turn passage of protons through the H-minus stripping foil in booster

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

    Gardner, C.

    Equations for transverse emittance growth due to multiple passes of circulating proton beam through the H-minus stripping foil in Booster were developed in [1]. These were based on simple principles of statistics and simple assumptions about the initial distribution of particles incident on the foil. It was assumed there that the foil dimensions and position of the incoming beam are such that all particles hit the foil on every turn around the machine. In the present note we assume only that all incoming H-minus ions from Linac hit the foil and are stripped of their electrons. The resulting protons circulatemore » indefinitely around the machine. Setups in which the foil width is reduced so that not all protons hit the foil on every turn are studied here by simulation. The aim is to determine the effectiveness of such setups in reducing the emittance growth of circulating proton beam during the injection of H-minus beam. The simulations also serve as a check of the equations developed in [1], and vice versa. The particulars of the simulation setup are given in Sections 1 through 11. Figures 1 through 12 show simulation results for the case in which all particles hit the foil on every turn. The results are in good agreement with those obtained from the equations of reference [1]. Figures 13 through 19 show simulation results for various setups in which the foil width is reduced. These results are summarized in Section 12. In all gures the horizontal axis gives the turn number. The unit of the vertical axis is micrometers ( m) in all plots of emittance.« less

  11. Safety evaluation of offset improvements for left-turn lanes

    DOT National Transportation Integrated Search

    2009-06-01

    The Federal Highway Administration (FHWA) organized 26 States to participate in the FHWA Low Cost Safety Improvements Pooled Fund Study as part of its strategic highway safety plan support effort. The purpose of the pooled fund study is to estimate t...

  12. Safety evaluation of offset improvements for left-turn lanes

    DOT National Transportation Integrated Search

    2009-06-01

    The Federal Highway Administration (FHWA) organized a pooled fund study of 26 States to evaluate low-cost safety strategies as part of its strategic highway safety effort. One of the strategies chosen to be evaluated for this study was offset improve...

  13. Left Panorama of Spirit's Landing Site

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Left Panorama of Spirit's Landing Site

    This is a version of the first 3-D stereo image from the rover's navigation camera, showing only the view from the left stereo camera onboard the Mars Exploration Rover Spirit. The left and right camera images are combined to produce a 3-D image.

  14. Rapidly progressing left atrial hemangiopericytoma.

    PubMed

    Nakamura, Tamami; Ito, Hiroshi; Sakata, Kensuke; Kobayashi, Yurio

    2015-11-01

    Cardiac hemangiopericytoma is a rare soft tissue tumor. We describe a case of hemangiopericytoma in the left atrium, which was diagnosed as myxoma preoperatively. A 70-year-old woman was admitted with heart failure. An echocardiogram showed a large myxoma-like mass in the left atrium, herniating into the left ventricle; therefore, an emergency operation was performed. Histological examination revealed a malignant hemangiopericytoma. The patient's postoperative course was uneventful, but she died due to a local recurrence 4 months after the operation. © The Author(s) 2014.

  15. The Left Atrio-Vertebral Ratio: a new simple means for assessing left atrial enlargement on Computed Tomography.

    PubMed

    Montillet, Marie; Baqué-Juston, Marie; Tasu, Jean-Pierre; Bertrand, Sandra; Berthier, Frédéric; Zarqane, Naïma; Brunner, Philippe

    2018-03-01

    The purpose of this study is to describe a new method to quickly estimate left atrial enlargement (LAE) on Computed Tomography. Left atrial (LA) volume was assessed with a 3D-threshold Hounsfield unit detection technique, including left atrial appendage and excluding pulmonary venous confluence, in 201 patients with ECG-gated 128-slice dual-source CT and indexed to body surface area. LA and vertebral axial diameter and area were measured at the bottom level of the right inferior pulmonary vein ostium. Ratio of LA diameter and surface on vertebra (LAVD and LAVA) were compared to LA volume. In accordance with the literature, a cutoff value of 78 ml/m 2 was chosen for maximal normal LA volume. 18% of LA was enlarged. The best cutoff values for LAE assessment were 2.5 for LAVD (AUC: 0.65; 95% CI: 0.58-0.73; sensitivity: 57%; specificity: 71%), and 3 for LAVA (AUC: 0.78; 95% CI: 0.72-0.84; sensitivity: 67%; specificity: 79%), with higher accuracy for LAVA (P=0.015). Inter-observer and intra-observer variability were either good or excellent for LAVD and LAVA (respective intraclass coefficients: 0.792 and 0.910; 0.912 and 0.937). A left atrium area superior to three times the vertebral area indicates LAE with high specificity. • Left atrial enlargement is a frequent condition associated with poor cardiac outcome. • Left atrial enlargement is highly time-consuming to diagnose on CT. • The left atrio-vertebral ratio quickly assesses left atrial enlargement. • A left atrial area > three times vertebral area is highly specific.

  16. The ontological turn meets the certainty of death.

    PubMed

    McDonald, Maryon

    2017-08-01

    The 'ontological turn' involves some anthropological points of long standing but the approaches recently coordinated into this turn have been presented as a 'call to arms', as shaking up 'mono-realist singularities' and as inherently political. This fighting talk has no doubt made important contributions to anthropology and insights from the ontological turn can help in anthropological understandings of medical practices. However, this paper contends that this helpfulness is also limited and that a call to arms may be inappropriate. This point is made through an ethnographic understanding of medical concern about the diagnosis of death.

  17. Flip Turns with Students

    ERIC Educational Resources Information Center

    Queeney, Kate

    2014-01-01

    Kate Queeney, a professor of chemistry at Smith College, turned to a former student to receive one-on-one instruction in swimming. The student, who had been unsure and scared in chemistry class, seemed like an entirely different person when teaching the teacher. This article describes how the author learned that there is something undeniably…

  18. Effects of novel oral anticoagulants on left atrial and left atrial appendage thrombi: an appraisal.

    PubMed

    Marsico, Fabio; Cecere, Milena; Parente, Antonio; Paolillo, Stefania; de Martino, Fabiana; Dellegrottaglie, Santo; Trimarco, Bruno; Perrone Filardi, Pasquale

    2017-02-01

    Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and predisposes to an increased risk of thromboembolic events. Patients affected by AF exhibit an increased risk of stroke compared with those in sinus rhythm, with the most common location of thrombi in the left atrial appendage. Until 2009, warfarin and other vitamin K antagonists were the only class of oral anticoagulants available. More recently, dabigatran, rivaroxaban, apixaban, and edoxaban have been approved by regulatory authorities for prevention of stroke in patients with non-valvular AF. Few data are available about the efficacy of novel oral anticoagulants for the treatment of left atrial and left atrial appendage thrombosis. Aim of this review is to summarize available evidence regarding the effectiveness of novel oral anticoagulants on left atrial appendage thrombosis.

  19. Left hemisphere regions are critical for language in the face of early left focal brain injury.

    PubMed

    Raja Beharelle, Anjali; Dick, Anthony Steven; Josse, Goulven; Solodkin, Ana; Huttenlocher, Peter R; Levine, Susan C; Small, Steven L

    2010-06-01

    A predominant theory regarding early stroke and its effect on language development, is that early left hemisphere lesions trigger compensatory processes that allow the right hemisphere to assume dominant language functions, and this is thought to underlie the near normal language development observed after early stroke. To test this theory, we used functional magnetic resonance imaging to examine brain activity during category fluency in participants who had sustained pre- or perinatal left hemisphere stroke (n = 25) and in neurologically normal siblings (n = 27). In typically developing children, performance of a category fluency task elicits strong involvement of left frontal and lateral temporal regions and a lesser involvement of right hemisphere structures. In our cohort of atypically developing participants with early stroke, expressive and receptive language skills correlated with activity in the same left inferior frontal regions that support language processing in neurologically normal children. This was true independent of either the amount of brain injury or the extent that the injury was located in classical cortical language processing areas. Participants with bilateral activation in left and right superior temporal-inferior parietal regions had better language function than those with either predominantly left- or right-sided unilateral activation. The advantage conferred by left inferior frontal and bilateral temporal involvement demonstrated in our study supports a strong predisposition for typical neural language organization, despite an intervening injury, and argues against models suggesting that the right hemisphere fully accommodates language function following early injury.

  20. Fast turn-on osmium coated cathode

    NASA Astrophysics Data System (ADS)

    Marrian, C. R. K.; Haas, G. A.; Shih, A.

    1984-03-01

    This abstract discloses a fast turn-on refractory coated cathode comprising a porous tungsten metal matrix impregnated with barium calcium aluminate and coated with osmium. The osmium coating has a planned series of interruptions with each interruption being on the order of several microns in width to thereby expose the tungsten. These interruptions permit the barium and oxygen from the impregnant to rise to the cathode surface during activation or reactivation to form a desired near monolayer of barium and oxygen to enhance electron emission. Thus, this cathode design provides a fast turn-on characteristic even after shelf storage.

  1. Turning around Newton's Second Law

    ERIC Educational Resources Information Center

    Goff, John Eric

    2004-01-01

    Conceptual and quantitative difficulties surrounding Newton's second law often arise among introductory physics students. Simply turning around how one expresses Newton's second law may assist students in their understanding of a deceptively simple-looking equation.

  2. What Lies Ahead (left-eye)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This is the left-eye version of the 3-D cylindrical-perspective mosaic showing the view south of the martian crater dubbed 'Bonneville.' The image was taken by the navigation camera on the Mars Exploration Rover Spirit. The rover will travel toward the Columbia Hills, seen here at the upper left. The rock dubbed 'Mazatzal' and the hole the rover drilled in to it can be seen at the lower left. The rover's position is referred to as 'Site 22, Position 32.' This image was geometrically corrected to make the horizon appear flat.

  3. The Left-Handed: "Their Sinister" History.

    ERIC Educational Resources Information Center

    Costas, Elaine Fowler

    The history of left-handedness can provide teachers and parents a better understanding of left-handed children and give those children more pride in their difference. No child should be made to feel that he or she is abnormal because of using the left hand, although some specific instruction for these students is necessary in handwriting. Many…

  4. Left-handedness and language lateralization in children.

    PubMed

    Szaflarski, Jerzy P; Rajagopal, Akila; Altaye, Mekibib; Byars, Anna W; Jacola, Lisa; Schmithorst, Vincent J; Schapiro, Mark B; Plante, Elena; Holland, Scott K

    2012-01-18

    This fMRI study investigated the development of language lateralization in left- and righthanded children between 5 and 18 years of age. Twenty-seven left-handed children (17 boys, 10 girls) and 54 age- and gender-matched right-handed children were included. We used functional MRI at 3T and a verb generation task to measure hemispheric language dominance based on either frontal or temporo-parietal regions of interest (ROIs) defined for the entire group and applied on an individual basis. Based on the frontal ROI, in the left-handed group, 23 participants (85%) demonstrated left-hemispheric language lateralization, 3 (11%) demonstrated symmetric activation, and 1 (4%) demonstrated right-hemispheric lateralization. In contrast, 50 (93%) of the right-handed children showed left-hemispheric lateralization and 3 (6%) demonstrated a symmetric activation pattern, while one (2%) demonstrated a right-hemispheric lateralization. The corresponding values for the temporo-parietal ROI for the left-handed children were 18 (67%) left-dominant, 6 (22%) symmetric, 3 (11%) right-dominant and for the right-handed children 49 (91%), 4 (7%), 1 (2%), respectively. Left-hemispheric language lateralization increased with age in both groups but somewhat different lateralization trajectories were observed in girls when compared to boys. The incidence of atypical language lateralization in left-handed children in this study was similar to that reported in adults. We also found similar rates of increase in left-hemispheric language lateralization with age between groups (i.e., independent of handedness) indicating the presence of similar mechanisms for language lateralization in left- and right-handed children. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. MedlinePlus.gov Turns 10!

    MedlinePlus

    ... Navigation Bar Home Current Issue Past Issues MedlinePlus.gov Turns 10! Past Issues / Fall 2008 Table of ... Photo courtesy of Michael Spencer, NIH NIH's MedlinePlus.gov , the popular, consumer-friendly health Web site produced ...

  6. Double-chambered left ventricle in a cat.

    PubMed

    Smith, Paul J; Tarazi, Marwan N; Ho, Siew Yen

    2014-06-01

    Double-chambered left ventricle is a rare congenital disorder in which the left ventricular cavity is subdivided into two cavities by an anomalous septum or muscle band. We describe a case of double-chambered left ventricle, most likely caused by the presence of excessive left ventricular bands, in an asymptomatic cat. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Presence of reduced regional left ventricular function even in the absence of left ventricular wall scar tissue in the long term after repair of an anomalous left coronary artery from the pulmonary artery.

    PubMed

    Nordmeyer, Sarah; Schmitt, Boris; Nasseri, Boris; Alexi-Meskishvili, Vladimir; Kuehne, Titus; Berger, Felix; Nordmeyer, Johannes

    2018-02-01

    We sought to assess left ventricular regional function in patients with and without left ventricular wall scar tissue in the long term after repair of an anomalous origin of the left coronary artery from the pulmonary artery. A total of 20 patients aged 12.8±7.4 years were assessed 10 (0.5-17) years after the repair of an anomalous origin of the left coronary artery from the pulmonary artery; of them, 10 (50%) patients showed left ventricular wall scar tissue on current cardiac MRI. Left ventricular regional function was assessed by two-dimensional speckle-tracking echocardiography in 10 patients with scar tissue and 10 patients without scar tissue and in 10 age-matched controls. In patients with scar tissue, MRI-derived left ventricular ejection fraction was significantly reduced compared with that in patients without scar tissue (51 versus 61%, p<0.05), and echocardiography-derived longitudinal strain was significantly reduced in five of six left ventricular areas compared with that in healthy controls (average relative reduction, 46%; p<0.05). In patients without scar tissue, longitudinal strain was significantly reduced in two of six left ventricular areas (average relative reduction, 23%; p<0.05) and circumferential strain was reduced in one of six left ventricular areas (relative reduction, 56%; p<0.05) compared with that in healthy controls. Regional left ventricular function is reduced even in patients without left ventricular wall scar tissue late after successful repair of an anomalous origin of the left coronary artery from the pulmonary artery. This highlights the need for meticulous lifelong follow-up in all patients with a repaired anomalous origin of the left coronary artery from the pulmonary artery.

  8. Memorization of Sequences of Movements of the Right or the Left Hand by Right- and Left-Handers: Vector Coding.

    PubMed

    Bobrova, E V; Bogacheva, I N; Lyakhovetskii, V A; Fabinskaja, A A; Fomina, E V

    2017-01-01

    In order to test the hypothesis of hemisphere specialization for different types of information coding (the right hemisphere, for positional coding; the left one, for vector coding), we analyzed the errors of right and left-handers during a task involving the memorization of sequences of movements by the left or the right hand, which activates vector coding by changing the order of movements in memorized sequences. The task was first performed by the right or the left hand, then by the opposite hand. It was found that both'right- and left-handers use the information about the previous movements of the dominant hand, but not of the non-dom" inant one. After changing the hand, right-handers use the information about previous movements of the second hand, while left-handers do not. We compared our results with the data of previous experiments, in which positional coding was activated, and concluded that both right- and left-handers use vector coding for memorizing the sequences of their dominant hands and positional coding for memorizing the sequences of non-dominant hand. No similar patterns of errors were found between right- and left-handers after changing the hand, which suggests that in right- and left-handersthe skills are transferred in different ways depending on the type of coding.

  9. Turning Points in the Development of Classical Musicians

    ERIC Educational Resources Information Center

    Gabor, Elena

    2011-01-01

    This qualitative study investigated the vocational socialization turning points in families of classical musicians. I sampled and interviewed 20 parent-child dyads, for a total of 46 interviews. Data analysis revealed that classical musicians' experiences were marked by 11 turning points that affected their identification with the occupation:…

  10. Minimum-fuel turning climbout and descent guidance of transport jets

    NASA Technical Reports Server (NTRS)

    Neuman, F.; Kreindler, E.

    1983-01-01

    The complete flightpath optimization problem for minimum fuel consumption from takeoff to landing including the initial and final turns from and to the runway heading is solved. However, only the initial and final segments which contain the turns are treated, since the straight-line climbout, cruise, and descent problems have already been solved. The paths are derived by generating fields of extremals, using the necessary conditions of optimal control together with singular arcs and state constraints. Results show that the speed profiles for straight flight and turning flight are essentially identical except for the final horizontal accelerating or decelerating turns. The optimal turns require no abrupt maneuvers, and an approximation of the optimal turns could be easily integrated with present straight-line climb-cruise-descent fuel-optimization algorithms. Climbout at the optimal IAS rather than the 250-knot terminal-area speed limit would save 36 lb of fuel for the 727-100 aircraft.

  11. Investigation on quench initiation and propagation characteristics of GdBCO coil co-wound with a stainless steel tape as turn-to-turn metallic insulation.

    PubMed

    Kim, Y G; Song, J B; Choi, Y H; Yang, D G; Kim, S G; Lee, H G

    2016-11-01

    This paper investigates the quench initiation and propagation characteristics of a metallic insulation (MI) coil by conducting thermal quench tests for a GdBCO single-pancake coil co-wound with a stainless steel tape as the turn-to-turn MI. The test results confirmed that the MI coil exhibited superior thermal and electrical stabilities compared to the conventional coils co-wound with organic insulation material because the operating current could flow along the radial direction due to the existence of a turn-to-turn contact when a local hot spot was generated. The results of the quench test at a heater current (I h ) of 12, 13, and 14 A indicate that the MI coil possesses a self-protecting characteristic resulting from the "current bypass" through the turn-to-turn contact. However, the test coil was not self-protecting at I h = 15 A because the Joule heat energy generated by the radial current flow was not completely dissipated due to the characteristic resistance of the metallic insulation tape and the non-superconducting materials, including the substrate, stabilizer, and buffer layers within the high-temperature superconductor (HTS) tape. Even though the MI coil possesses superior thermal and electrical stability relative to those of conventional HTS coils co-wound with an organic material as turn-to-turn insulation, it is essential to consider the critical role of the Joule heat energy resulting from the operating current and stored magnetic energy as well as the characteristic resistances in order to further develop self-protective 2G HTS magnets.

  12. Preoperative left ventricular ejection fraction and left atrium reverse remodeling after mitral regurgitation surgery.

    PubMed

    Machado, Lucia R; Meneghelo, Zilda M; Le Bihan, David C S; Barretto, Rodrigo B M; Carvalho, Antonio C; Moises, Valdir A

    2014-11-06

    Left atrium enlargement has been associated with cardiac events in patients with mitral regurgitation (MR). Left atrium reverse remodeling (LARR) occur after surgical correction of MR, but the preoperative predictors of this phenomenon are not well known. It is therefore important to identify preoperative predictors for postoperative LARR. We enrolled 62 patients with chronic severe MR (prolapse or flail leaflet) who underwent successful mitral valve surgery (repair or replacement); all with pre- and postoperative echocardiography. LARR was defined as a reduction in left atrium volume index (LAVI) of ≥ 25%. Stepwise multiple regression analysis was used to identify independent predictors of LARR. LARR occurred in 46 patients (74.2%), with the mean LAVI decreasing from 85.5 mL/m2 to 49.7 mL/m2 (p <0.001). These patients had a smaller preoperative left ventricular systolic volume (p =0.022) and a higher left ventricular ejection fraction (LVEF) (p =0.034). LVEF was identified as the only preoperative variable significantly associated with LARR (odds ratio, 1.086; 95% confidence interval, 1.002-1.178). A LVEF cutoff value of 63.5% identified patients with LARR of ≥ 25% with a sensitivity of 71.7% and a specificity of 56.3%. LARR occurs frequently after mitral valve surgery and is associated with preoperative LVEF higher than 63.5%.

  13. Class Identification Efficacy in Piecewise GMM with Unknown Turning Points

    ERIC Educational Resources Information Center

    Ning, Ling; Luo, Wen

    2018-01-01

    Piecewise GMM with unknown turning points is a new procedure to investigate heterogeneous subpopulations' growth trajectories consisting of distinct developmental phases. Unlike the conventional PGMM, which relies on theory or experiment design to specify turning points a priori, the new procedure allows for an optimal location of turning points…

  14. Understanding Learning: Assessment in the Turning Points School

    ERIC Educational Resources Information Center

    Center for Collaborative Education, 2005

    2005-01-01

    Turning Points helps middle schools create challenging, caring, and equitable learning communities that meet the needs of young adolescents as they reach the "turning point" between childhood and adulthood. Based on more than a decade of research and experience, this comprehensive school reform model focuses on improving student learning through…

  15. Case Study Using Ultrasound to Treat /[turned r]/

    ERIC Educational Resources Information Center

    Modha, Geetanjalee; Bernhardt, B. May; Church, Robyn; Bacsfalvi, Penelope

    2008-01-01

    Background: Ultrasound has shown promise as visual feedback in remediation of /[turned r]/.Aims: To compare treatment for [turned r] with and without ultrasound.Methods & Procedures: A Canadian English-speaking adolescent participated in a case study with a no treatment baseline, alternating treatment blocks with and without ultrasound and a…

  16. History of Education in Canada: Historiographic "Turns" and Widening Horizons

    ERIC Educational Resources Information Center

    Bruno-Jofré, Rosa

    2014-01-01

    This paper explores major historiographic "turns" in history of education with a focus, although not exclusively, on English-speaking Canada. It addresses the transformative intellectual impact of the turn toward social history on the history of education, the impact of cultural history and the linguistic turn, the reception of Michel…

  17. Aberrant left subclavian artery occlusion in right-sided aortic artery associated with left cerebral infarction: A case report.

    PubMed

    Tempaku, Akira; Kuroiwa, Terumasa; Nishio, Akimasa

    2018-06-01

    Purpose Right-sided aortic arch is a rare vessel anomaly with an incidence of 0.1% worldwide. Supra-aortic branches form a mirror image of the left-sided aortic arch or an aberrant left subclavian artery associated with Kommerell diverticulum. Most patients are diagnosed by a difference in blood pressure in each upper extremity or by the presence of left subclavian steal syndrome in their younger age. The diagnosis of onset of ischemic stroke in middle age is rare. Methods We present the case of a female patient who presented with an ischemic stroke in the left posterior circulation area. She had no history of congenital heart malformation. We performed head magnetic resonance imaging, cerebral angiography, and enhanced computed tomography of the aortic arch and major branches. Results The patient had a right-sided aortic arch and an aberrant left subclavian artery. The left subclavian artery was occluded at the proximal portion with a fibrous string. Collateral flow in the anterior cervical subcutaneous area supported left limb perfusion. Conclusion An atheromatous change reduced shunt flow via collateral networks at the anterior cervical region. Congenital subclavian steal supported the ischemic stroke.

  18. Human Rights Education and the Post Secular Turn

    ERIC Educational Resources Information Center

    Bowie, Bob

    2012-01-01

    This article questions whether human rights education (HRE) scholarship is responding adequately to the post secular turn in thinking about the place and nature of religion in society. Here the post secular turn is used to describe the discrediting of secularisation theory, the recognition of religion as an enduring and pervasive global cultural…

  19. Model-independent analysis of the Fermilab Tevatron turn-by-turn beam position monitor measurements

    NASA Astrophysics Data System (ADS)

    Petrenko, A. V.; Valishev, A. A.; Lebedev, V. A.

    2011-09-01

    Coherent transverse beam oscillations in the Tevatron were analyzed with the model-independent analysis (MIA) technique. This allowed one to obtain the model-independent values of coupled betatron amplitudes, phase advances, and dispersion function around the ring from a single dipole kick measurement. In order to solve the MIA mode mixing problem which limits the accuracy of determination of the optical functions, we have developed a new technique of rotational MIA mode untangling. The basic idea is to treat each beam position monitor (BPM) as two BPMs separated in a ring by exactly one turn. This leads to a simple criterion of MIA mode separation: the betatron phase advance between any BPM and its counterpart shifted by one turn should be equal to the betatron tune and therefore should not depend on the BPM position in the ring. Furthermore, we describe a MIA-based technique to locate vibrating magnets in a storage ring.

  20. Left ventricular to left atrial communication secondary to a paraaortic abscess: color flow Doppler documentation.

    PubMed

    Fisher, E A; Estioko, M R; Stern, E H; Goldman, M E

    1987-07-01

    Aortic root abscess occurs frequently in aortic prosthetic valve infective endocarditis. The present echocardiographic report documents a ruptured abscess that led to a direct communication between the left ventricular outflow tract and the left atrium confirmed by real-time (color flow) Doppler imaging.

  1. Postoperative pulmonary hypertensive crisis caused by inverted left atrial appendage after cardiopulmonary bypass surgery for congenital heart disease in a neonate.

    PubMed

    Zhao, Qifeng; Hu, Xingti

    2013-09-01

    Postoperative pulmonary hypertensive crisis (PHC) caused by an inverted left atrial appendage (ILAA) is a rare complication following cardiac surgery. We present a case of 23 day-old male infant who developed postoperative PHC attacks after undergoing cardiopulmonary bypass (CPB) surgery for repair of the coactation of aorta. A hyperechogenic left atrial mass was detected via bedside transthoracic echocardiography (TTE), which was identified as an ILAA and corrected following repeat surgery. In this case, both the negative pressure in vent catheter and the long left atrial appendage (LAA) with a narrow base led to an irreversible ILAA. As in this neonate, ILAA had significant influence on the left atrial volume and caused PHC since the ILAA was located on the mitral valve orifice and interfered with the blood flow through the valve. Therefore, we recommend that the vent catheter should be turned off before removing to avoid this potential complication. Additionally, LAA should be carefully inspected after CPB surgery, and intra-operative and post-operative transoesophageal echocardiography (TEE) should be performed to detect ILAA intraoperatively so as to avoid the reoperation. When an ILAA is diagnosed postoperatively, whether conservative treatment or surgery will depend on the balance of benefit and risk for a particular patient. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

  2. Turn Openings in Academic Talk: Where Goals and Roles Intersect

    ERIC Educational Resources Information Center

    Evison, Jane

    2013-01-01

    This study uses Corpus Linguistic (CL) techniques to explore multiple turn openings in conjunction with comparative measures of turn-initial priming (the proportion of occurrences of a form that are turn-initial). Using a benchmark corpus of casual conversation as a point of comparison, six frequent items which have a particularly strong affinity…

  3. Compensations for increased rotational inertia during human cutting turns.

    PubMed

    Qiao, Mu; Brown, Brian; Jindrich, Devin L

    2014-02-01

    Locomotion in a complex environment is often not steady state, but unsteady locomotion (stability and maneuverability) is not well understood. We investigated the strategies used by humans to perform sidestep cutting turns when running. Previous studies have argued that because humans have small yaw rotational moments of inertia relative to body mass, deceleratory forces in the initial velocity direction that occur during the turning step, or 'braking' forces, could function to prevent body over-rotation during turns. We tested this hypothesis by increasing body rotational inertia and testing whether braking forces during stance decreased. We recorded ground reaction force and body kinematics from seven participants performing 45 deg sidestep cutting turns and straight running at five levels of body rotational inertia, with increases up to fourfold. Contrary to our prediction, braking forces remained consistent at different rotational inertias, facilitated by anticipatory changes to body rotational speed. Increasing inertia revealed that the opposing effects of several turning parameters, including rotation due to symmetrical anterior-posterior forces, result in a system that can compensate for fourfold changes in rotational inertia with less than 50% changes to rotational velocity. These results suggest that in submaximal effort turning, legged systems may be robust to changes in morphological parameters, and that compensations can involve relatively minor adjustments between steps to change initial stance conditions.

  4. Compensations for increased rotational inertia during human cutting turns

    PubMed Central

    Qiao, Mu; Brown, Brian; Jindrich, Devin L.

    2014-01-01

    Locomotion in a complex environment is often not steady state, but unsteady locomotion (stability and maneuverability) is not well understood. We investigated the strategies used by humans to perform sidestep cutting turns when running. Previous studies have argued that because humans have small yaw rotational moments of inertia relative to body mass, deceleratory forces in the initial velocity direction that occur during the turning step, or ‘braking’ forces, could function to prevent body over-rotation during turns. We tested this hypothesis by increasing body rotational inertia and testing whether braking forces during stance decreased. We recorded ground reaction force and body kinematics from seven participants performing 45 deg sidestep cutting turns and straight running at five levels of body rotational inertia, with increases up to fourfold. Contrary to our prediction, braking forces remained consistent at different rotational inertias, facilitated by anticipatory changes to body rotational speed. Increasing inertia revealed that the opposing effects of several turning parameters, including rotation due to symmetrical anterior–posterior forces, result in a system that can compensate for fourfold changes in rotational inertia with less than 50% changes to rotational velocity. These results suggest that in submaximal effort turning, legged systems may be robust to changes in morphological parameters, and that compensations can involve relatively minor adjustments between steps to change initial stance conditions. PMID:24115061

  5. U-Turns at signalized intersections.

    DOT National Transportation Integrated Search

    2004-06-01

    The objectives of the study were to examine the safety consequences from the installation of U-turns at signalized intersections in Kentucky and to develop a set of guidelines for using this alternative in the future. The literature review indicated ...

  6. 32 CFR 935.135 - Turns.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... center of the road, except that on multi-lane roads of one-way traffic flow he may make the turn only... motion from a stopped position, or change from or merge into a lane of traffic, until he can safely make...

  7. 32 CFR 935.135 - Turns.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... center of the road, except that on multi-lane roads of one-way traffic flow he may make the turn only... motion from a stopped position, or change from or merge into a lane of traffic, until he can safely make...

  8. 32 CFR 935.135 - Turns.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... center of the road, except that on multi-lane roads of one-way traffic flow he may make the turn only... motion from a stopped position, or change from or merge into a lane of traffic, until he can safely make...

  9. 32 CFR 935.135 - Turns.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... center of the road, except that on multi-lane roads of one-way traffic flow he may make the turn only... motion from a stopped position, or change from or merge into a lane of traffic, until he can safely make...

  10. 32 CFR 935.135 - Turns.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... center of the road, except that on multi-lane roads of one-way traffic flow he may make the turn only... motion from a stopped position, or change from or merge into a lane of traffic, until he can safely make...

  11. Persistent left superior vena cava

    PubMed Central

    Tyrak, Kamil W; Hołda, Mateusz K; Koziej, Mateusz; Piątek, Katarzyna; Klimek-Piotrowska, Wiesława

    2017-01-01

    Summary Persistent left superior vena cava (PLSVC) is the most common congenital malformation of thoracic venous return and is present in 0.3 to 0.5% of individuals in the general population. This heart specimen was dissected from a 35-yearold male cadaver whose cause of death was determined as non-cardiac. The heart was examined and we found a PLSVC draining into the coronary sinus. The right superior vena cava was present with a small-diameter ostium. An anomalous pulmonary vein pattern was observed; there was a common trunk to the left superior and left inferior pulmonary veins (diameter 17.8 mm) and an additional middle right pulmonary vein (diameter 2.7 mm) with two classic right pulmonary veins. The PLSVC draining into the coronary sinus had led to its enlargement, which could have altered the cardiac haemodynamics by significantly reducing the size of the left atrium and impeding its outflow via the mitral valve. PMID:28759082

  12. Alternative Fuels Data Center: DeKalb County Turns Trash to Gas

    Science.gov Websites

    DeKalb County Turns Trash to Gas to someone by E-mail Share Alternative Fuels Data Center: DeKalb County Turns Trash to Gas on Facebook Tweet about Alternative Fuels Data Center: DeKalb County Turns Trash to Gas on Twitter Bookmark Alternative Fuels Data Center: DeKalb County Turns Trash to Gas on

  13. NEHRP turns 40

    USGS Publications Warehouse

    Leith, William S.

    2017-01-01

    This year, the National Earthquake Hazards Reduction Program (NEHRP) turns 40, four decades since the Earthquake Hazards Reduction Act of 1977 was enacted establishing the Program, spurring numerous federal, state, and community actions to reduce earthquake losses in the U.S.A. and its territories and setting a standard for earthquake loss‐reduction projects internationally. Four agencies are partners in NEHRP: the Federal Emergency Management Agency (FEMA), the National Institute of Standards and Technology (NIST, the lead agency), the National Science Foundation (NSF), and the U.S. Geological Survey (USGS).

  14. Characterization of jellyfish turning using 3D-PTV

    NASA Astrophysics Data System (ADS)

    Xu, Nicole; Dabiri, John

    2017-11-01

    Aurelia aurita are oblate, radially symmetric jellyfish that consist of a gelatinous bell and subumbrellar muscle ring, which contracts to provide motive force. Swimming is typically modeled as a purely vertical motion; however, asymmetric activations of swim pacemakers (sensory organs that innervate the muscle at eight locations around the bell margin) result in turning and more complicated swim behaviors. More recent studies have examined flow fields around turning jellyfish, but the input/output relationship between locomotive controls and swim trajectories is unclear. To address this, bell kinematics for both straight swimming and turning are obtained using 3D particle tracking velocimetry (3D-PTV) by injecting biocompatible elastomer tags into the bell, illuminating the tank with ultraviolet light, and tracking the resulting fluorescent particles in a multi-camera setup. By understanding these kinematics in both natural and externally controlled free-swimming animals, we can connect neuromuscular control mechanisms to existing flow measurements of jellyfish turning for applications in designing more energy efficient biohybrid robots and underwater vehicles. NSF GRFP.

  15. The influence of rear turn-signal characteristics on crash risk.

    PubMed

    Sullivan, John M; Flannagan, Michael J

    2012-02-01

    The relationship between the relative risk of a rear-end collision during a turn, merge, or lane change maneuver and the characteristics of the rear turn-signal configuration was examined using crash data from seven states in the United States. Rear turn-signal characteristics-including color, optics, separation, and light source-were identified for 55 vehicle models and used in a logistic regression analysis to model the odds of a rear-end collision. Additional variables including driver demographics (gender, age), vehicle age, and light condition were also modeled. Risk was assessed using a contrast group of striking vehicles in similar collisions. The results suggest that the odds of being the struck vehicle were 3% to 28% lower among vehicles equipped with amber versus red turn signals. Although the analysis suggests that there may be a safety benefit associated with amber rear turn signals, it is unclear whether turn-signal color alone is responsible. The results suggest that aspects of a vehicle's rear signal characteristics may influence crash risk. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. High-Intensity Interval Training for Severe Left Ventricular Dysfunction Treated with Left Ventricular Assist Device.

    PubMed

    Ugata, Yusuke; Wada, Hiroshi; Sakakura, Kenichi; Ibe, Tatsuro; Ito, Miyuki; Ikeda, Nahoko; Fujita, Hideo; Momomura, Shin-Ichi

    2018-01-27

    Aerobic training based on anaerobic threshold (AT) is well-known to improve cardiac function, exercise capacity, and long-term outcomes of patients with heart failure. Recent reports suggested that high-intensity interval training (HIIT) for patients with cardiovascular disease may improve cardiopulmonary exercise capacity. We present a 61-year-old male patient of severe left ventricular dysfunction with left ventricular assisted device (LVAD). Following HIIT for 8 weeks, exercise capacity and muscle strength have improved without worsening left ventricular function. Our case showed the possibility that HIIT was feasible and effective even in patients with LVAD.

  17. Implantation of a HeartMate II left ventricular assist device via left thoracotomy.

    PubMed

    Cho, Yang Hyun; Deo, Salil V; Schirger, John A; Pereira, Naveen L; Stulak, John M; Park, Soon J

    2012-11-01

    Left thoracotomy was used as an approach for the implantation of pulsatile ventricular assist devices. Avoiding the standard approach of median sternotomy is attractive in patients undergoing complicated redo cardiac surgery, especially with prior mediastinal radiation. We report a case of the use of left thoracotomy for the implantation of the HeartMate II axial-flow pump. Copyright © 2012 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  18. Coexistence of congenital left ventricular aneurysm and prominent left ventricular trabeculation in a patient with LDB3 mutation: a case report.

    PubMed

    Shan, Shengshuai; He, Xiaoxiao; He, Lin; Wang, Min; Liu, Chengyun

    2017-08-19

    The coexistence of congenital left ventricular aneurysm and abnormal cardiac trabeculation with gene mutation has not been reported previously. Here, we report a case of coexisting congenital left ventricular aneurysm and prominent left ventricular trabeculation in a patient with LIM domain binding 3 gene mutation. A 30-year-old Asian man showed paroxysmal sinus tachycardia and Q waves in an electrocardiogram health check. There were no specific findings in physical examinations and serological tests. A coronary-computed tomography angiography check showed normal coronary artery and no coronary stenosis. Both left ventricle contrast echocardiography and cardiac magnetic resonance showed rare patterns of a combination of an apical aneurysm-like out-pouching structure with a wide connection to the left ventricle and prominent left ventricular trabecular meshwork. High-throughput sequencing examinations showed a novel mutation in the LDB3 gene (c.C793>T; p.Arg265Cys). Our finding indicates that the phenotypic expression of two heart conditions, congenital left ventricular aneurysm and prominent left ventricular trabeculation, although rare, can occur simultaneously with LDB3 gene mutation. Congenital left ventricular aneurysm and prominent left ventricular trabeculation may share the same genetic background.

  19. Acute left main coronary artery occlusion

    PubMed Central

    Burgazli, K. Mehmet; Bilgin, Mehmet; Soydan, Nedim; Chasan, Ridvan; Erdogan, Ali

    2013-01-01

    The treatment of an acute left main coronary artery occlusion still poses a challenge. In this case report we present a 50-year-old patient with an acute occlusion of the left main artery. After a successful angioplasty without “stenting” due to the complexity of the stenosis the patient underwent a successful bypass surgery. We discuss the therapeutic options of acute left main occlusion regarding medical, interventional and surgical options. PMID:24353543

  20. Sex differences in left/right confusion.

    PubMed

    Jordan, Kirsten; Wüstenberg, Torsten; Jaspers-Feyer, Fern; Fellbrich, Anja; Peters, Michael

    2006-01-01

    In agreement with the literature, females (n=269) gave themselves significantly poorer ratings than males (n=164) in evaluating their ability to make fast and accurate left/right judgments. In order to evaluate the ecological validity of the self-ratings, subjects were tested on a task that required fast and accurate left/right judgments, on a mental rotation task, and on a task that required navigation of a virtual maze. The correlations between the performances and self-ratings were computed. Both males and females who gave themselves very poor LRC (left/right confusion) ratings had significantly lower accuracy scores on the left/right judgement task than males and females with average ratings, but there was no sex-specific relation between LRC ratings and left/right judgements that would explain why females give themselves lower LRC ratings. For females only, a weak correlation between LRC scores and the learning of the virtual maze was observed, but no significant correlations were observed between LRC scores and mental rotation performance. We conclude that self-ratings on left/right confusion questions, although they yield reliable sex differences, are poor predictors of actual performance on spatial tasks that involve left/right judgements. Thus, and in support of earlier speculations (Sholl and Egeth, 1981; Teng and Lee, 1982; Williams et al., 1993), the principal cause of the marked sex differences in LRC self-ratings likely lies in a greater willingness of females to rate themselves more poorly on questions of this type than is the case for men.

  1. Positive Association of Video Game Playing with Left Frontal Cortical Thickness in Adolescents

    PubMed Central

    Kühn, Simone; Lorenz, Robert; Banaschewski, Tobias; Barker, Gareth J.; Büchel, Christian; Conrod, Patricia J.; Flor, Herta; Garavan, Hugh; Ittermann, Bernd; Loth, Eva; Mann, Karl; Nees, Frauke; Artiges, Eric; Paus, Tomas; Rietschel, Marcella; Smolka, Michael N.; Ströhle, Andreas; Walaszek, Bernadetta; Schumann, Gunter; Heinz, Andreas; Gallinat, Jürgen

    2014-01-01

    Playing video games is a common recreational activity of adolescents. Recent research associated frequent video game playing with improvements in cognitive functions. Improvements in cognition have been related to grey matter changes in prefrontal cortex. However, a fine-grained analysis of human brain structure in relation to video gaming is lacking. In magnetic resonance imaging scans of 152 14-year old adolescents, FreeSurfer was used to estimate cortical thickness. Cortical thickness across the whole cortical surface was correlated with self-reported duration of video gaming (hours per week). A robust positive association between cortical thickness and video gaming duration was observed in left dorsolateral prefrontal cortex (DLPFC) and left frontal eye fields (FEFs). No regions showed cortical thinning in association with video gaming frequency. DLPFC is the core correlate of executive control and strategic planning which in turn are essential cognitive domains for successful video gaming. The FEFs are a key region involved in visuo-motor integration important for programming and execution of eye movements and allocation of visuo-spatial attention, processes engaged extensively in video games. The results may represent the biological basis of previously reported cognitive improvements due to video game play. Whether or not these results represent a-priori characteristics or consequences of video gaming should be studied in future longitudinal investigations. PMID:24633348

  2. Transparent lattice characterization with gated turn-by-turn data of diagnostic bunch train

    NASA Astrophysics Data System (ADS)

    Li, Yongjun; Cheng, Weixing; Ha, Kiman; Rainer, Robert

    2017-11-01

    Methods of characterization of a storage ring's lattice have traditionally been intrusive to routine operations. More importantly, the lattice seen by particles can drift with the beam current due to collective effects. To circumvent this, we have developed a novel approach for dynamically characterizing a storage ring's lattice that is transparent to operations. Our approach adopts a dedicated filling pattern which has a short, separate diagnostic bunch train (DBT). Through the use of a bunch-by-bunch feedback system, the DBT can be selectively excited on demand. Gated functionality of a beam position monitor system is capable of collecting turn-by-turn data of the DBT, from which the lattice can then be characterized after excitation. As the DBT comprises only about one percent of the total operational bunches, the effects of its excitation are negligible to users. This approach allows us to localize the distributed quadrupolar wakefields generated in the storage ring vacuum chamber during beam accumulation. While effectively transparent to operations, our approach enables us to dynamically control the beta beat and phase beat, and unobtrusively optimize performance of the National Synchrotron Light Source-II accelerator during routine operations.

  3. Transparent lattice characterization with gated turn-by-turn data of diagnostic bunch train

    DOE PAGES

    Li, Yongjun; Cheng, Weixing; Ha, Kiman; ...

    2017-11-21

    Methods of characterization of a storage ring's lattice have traditionally been intrusive to routine operations. More importantly, the lattice seen by particles can drift with the beam current due to collective effects. To circumvent this, we have developed a novel approach for dynamically characterizing a storage ring's lattice that is transparent to operations. Our approach adopts a dedicated filling pattern which has a short, separate Diagnostic Bunch-Train (DBT). Through the use of a bunch-by-bunch feedback system, the DBT can be selectively excited on-demand. Gated functionality of a beam position monitor system is capable of collecting turn-by-turn data of the DBT,more » from which the lattice can then be characterized after excitation. As the DBT comprises only about one percent of the total operational bunches, the effects of its excitation are negligible to users. Therefore, this approach allows us to localize the distributed quadrupolar wake fields generated in the storage ring vacuum chamber during beam accumulation. While effectively transparent to operations, our approach enables us to dynamically control the beta-beat and phase-beat, and unobtrusively optimize performance of National Synchrotron Light Source-II accelerator during routine operations.« less

  4. Anosognosia for hemiparesis after left-sided stroke.

    PubMed

    Baier, Bernhard; Vucurevic, Goran; Müller-Forell, Wibke; Glassl, Oliver; Geber, Christian; Dieterich, Marianne; Karnath, Hans-Otto

    2014-12-01

    In patients with left-sided lesions, anosognosia for hemiparesis (AHP) seems to be a rare phenomenon. It has been discussed whether this rareness might be due to an inevitable bias due to language dysfunction and whether the left hemisphere's role for our self-awareness of motor actions thus is underestimated. By applying functional magnetic resonance imaging (fMRI) we examined whether patients with AHP following a left hemisphere stroke show a regular, left-sided or a reversed, right-sided lateralization of language functions. Only the former observation would argue for an original role of the left hemisphere in self-awareness about limb function. In a consecutive series of 44 acute left-sided stroke patients, only one patient (=2%) was identified showing AHP. In this case, we could verify by using fMRI that lateralization of AHP and spatial neglect on the one hand and of language functions on the other hand were reversed. The present single case observation thus argues against an original role of the left hemisphere in self-awareness about limb function. We discuss the data in the context of previous observations in the literature. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Density of Plutonium Turnings Generated from Machining Activities

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

    Gonzales, John Robert; Vigil, Duane M.; Jachimowski, Thomas A.

    The purpose of this project was to determine the density of plutonium (Pu) turnings generated from the range of machining activities, using both surrogate material and machined Pu turnings. Verify that 500 grams (g) of plutonium will fit in a one quart container using a surrogate equivalent volume and that 100 grams of Pu will fit in a one quart Savy container.

  6. Acute decrease of left ventricular mechanical dyssynchrony and improvement of contractile state and energy efficiency after left ventricular restoration.

    PubMed

    Schreuder, Jan J; Castiglioni, Alessandro; Maisano, Francesco; Steendijk, Paul; Donelli, Andrea; Baan, Jan; Alfieri, Ottavio

    2005-01-01

    Surgical left ventricular restoration by means of endoventricular patch aneurysmectomy in patients with postinfarction aneurysm should result in acute improved left ventricular performance by decreasing mechanical dyssynchrony and increasing energy efficiency. Nine patients with left ventricular postinfarction aneurysm were studied intraoperatively before and after ventricular restoration with a conductance volume catheter to analyze pressure-volume relationships, energy efficiency, and mechanical dyssynchrony. The end-systolic elastance was used as a load-independent index of contractile state. Left ventricular energy efficiency was calculated from stroke work and total pressure-volume area. Segmental volume changes perpendicular to the long axis were used to calculate mechanical dyssynchrony. Statistical analysis was performed with the paired t test and least-squares linear regression. Endoventricular patch aneurysmectomy reduced end-diastolic volume by 37% (P < .001), with unchanged stroke volume. Systolic function improved, as derived from increased +dP/dt(max), by 42% (P < .03), peak ejection rate by 28% (P < .02), and ejection fraction by 16% (P < .0002). Early diastolic function improved, as shown by reduction of -dP/dt(max) by 34% (P < .006) and shortened tau by 30% (P < .001). Left ventricular end-systolic elastance increased from 1.2 +/- 0.6 to 2.2 +/- 1 mm Hg/mL (P < .001). Left ventricular energy efficiency increased by 36% (P < .002). Left ventricular mechanical dyssynchrony decreased during systole by 33% (P < .001) and during diastole by 20% (P < .005). Left ventricular restoration induced acute improvements in contractile state, energy efficiency, and relaxation, together with a decrease in left ventricular mechanical dyssynchrony.

  7. Clinical determinants and consequences of left ventricular hypertrophy.

    PubMed

    Messerli, F H

    1983-09-26

    The left ventricle adapts to an increased afterload such as that produced by arterial hypertension with concentric left ventricular hypertrophy. However, this adaptive process can be modified by a variety of physiologic and pathophysiologic states. Progressive aging, black race, and perhaps disorders with an increased sympathetic outflow seem to accelerate left ventricular hypertrophy. Obesity and other high cardiac output states predominantly produce dilatation of the left ventricle, and their combination with arterial hypertension results in eccentric left ventricular hypertrophy. Similarly, endurance exercise increases left ventricular volume more than wall thickness, whereas isometric exercise produces an increase in wall thickness only. The presence or absence of some physiologic and pathogenetic factors has direct implication on the assessment of what constitutes a "normal" left ventricular structure and function. Left ventricular hypertrophy has been shown to increase ventricular ectopic impulse generation and to put patients at a high risk of sudden death. Moreover, the increase in myocardial mass lowers coronary reserve and enhances cardiac oxygen requirements. Thus, the presence of left ventricular hypertrophy has to be considered as an ominous sign rather than as a benign adaptive process.

  8. Prediction and analysis of beta-turns in proteins by support vector machine.

    PubMed

    Pham, Tho Hoan; Satou, Kenji; Ho, Tu Bao

    2003-01-01

    Tight turn has long been recognized as one of the three important features of proteins after the alpha-helix and beta-sheet. Tight turns play an important role in globular proteins from both the structural and functional points of view. More than 90% tight turns are beta-turns. Analysis and prediction of beta-turns in particular and tight turns in general are very useful for the design of new molecules such as drugs, pesticides, and antigens. In this paper, we introduce a support vector machine (SVM) approach to prediction and analysis of beta-turns. We have investigated two aspects of applying SVM to the prediction and analysis of beta-turns. First, we developed a new SVM method, called BTSVM, which predicts beta-turns of a protein from its sequence. The prediction results on the dataset of 426 non-homologous protein chains by sevenfold cross-validation technique showed that our method is superior to the other previous methods. Second, we analyzed how amino acid positions support (or prevent) the formation of beta-turns based on the "multivariable" classification model of a linear SVM. This model is more general than the other ones of previous statistical methods. Our analysis results are more comprehensive and easier to use than previously published analysis results.

  9. Congenital left atrial appendage aneurysm

    PubMed Central

    Wang, Bin; Li, He; Zhang, Li; He, Lin; Zhang, Jing; Liu, Cong; Wang, Jing; Lv, Qing; Shang, Xiaoke; Liu, Jinping; Xie, Mingxing

    2018-01-01

    Abstract Rationale: Left atrial appendage aneurysms (LAAA) are rare. Patients with LAAA are often diagnosed incidentally or after cardiac tachyarrhythmia or systemic thromboembolism happen. Early diagnosis and surgical resection is of utmost importance to prevent hazardous adverse events. Patient concerns: We present a case of 46-year-old man with congenital LAAA. The individual in this manuscript has given written informed consent to publish these case details. Diagnoses: Imaging studies, such as echocardiography, cardiovascular computed tomography (CT) and magnetic resonance imaging (MRI), demonstrated the large cavity arising from the left atrial appendage. The diagnosis of LAAA was confirmed. Interventions: The patient underwent an aneurysmectomy without any complications. Outcomes: TTE confirmed the disappearance of the LAAA from the left parasternal short-axis view of the aortic root postoperatively. The patient remained asymptomatic without any adverse events at his 3-month follow-up visits. Lessons: The associated high risk of life-threatening complications and the relative ease of surgical removal suggest that prompt evaluation should be considered in patients with lesions adjacent to the left heart border. PMID:29480827

  10. Effects of dual task on turning ability in stroke survivors and older adults.

    PubMed

    Hollands, K L; Agnihotri, D; Tyson, S F

    2014-09-01

    Turning is an integral component of independent mobility in which stroke survivors frequently fall. This study sought to measure the effects of competing cognitive demands on the stepping patterns of stroke survivors, compared to healthy age-match adults, during turning as a putative mechanism for falls. Walking and turning (90°) was assessed under single (walking and turning alone) and dual task (subtracting serial 3s while walking and turning) conditions using an electronic, pressure-sensitive walkway. Dependent measures were time to turn, variability in time to turn, step length, step width and single support time during three steps of the turn. Turning ability in single and dual task conditions was compared between stroke survivors (n=17, mean ± SD: 59 ± 113 months post-stroke, 64 ± 10 years of age) and age-matched healthy counterparts (n=15). Both groups took longer, were more variable, tended to widen the second step and, crucially, increased single support time on the inside leg of the turn while turning and distracted. Increased single support time during turning may represent biomechanical mechanism, within stepping patterns of turning under distraction, for increased risk of falls for both stroke survivors and older adults. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.

  11. Using support vector machine to predict beta- and gamma-turns in proteins.

    PubMed

    Hu, Xiuzhen; Li, Qianzhong

    2008-09-01

    By using the composite vector with increment of diversity, position conservation scoring function, and predictive secondary structures to express the information of sequence, a support vector machine (SVM) algorithm for predicting beta- and gamma-turns in the proteins is proposed. The 426 and 320 nonhomologous protein chains described by Guruprasad and Rajkumar (Guruprasad and Rajkumar J. Biosci 2000, 25,143) are used for training and testing the predictive model of the beta- and gamma-turns, respectively. The overall prediction accuracy and the Matthews correlation coefficient in 7-fold cross-validation are 79.8% and 0.47, respectively, for the beta-turns. The overall prediction accuracy in 5-fold cross-validation is 61.0% for the gamma-turns. These results are significantly higher than the other algorithms in the prediction of beta- and gamma-turns using the same datasets. In addition, the 547 and 823 nonhomologous protein chains described by Fuchs and Alix (Fuchs and Alix Proteins: Struct Funct Bioinform 2005, 59, 828) are used for training and testing the predictive model of the beta- and gamma-turns, and better results are obtained. This algorithm may be helpful to improve the performance of protein turns' prediction. To ensure the ability of the SVM method to correctly classify beta-turn and non-beta-turn (gamma-turn and non-gamma-turn), the receiver operating characteristic threshold independent measure curves are provided. (c) 2008 Wiley Periodicals, Inc.

  12. Impaired Left Atrial Strain as a Predictor of New-onset Atrial Fibrillation After Aortic Valve Replacement Independently of Left Atrial Size.

    PubMed

    Pessoa-Amorim, Guilherme; Mancio, Jennifer; Vouga, Luís; Ribeiro, José; Gama, Vasco; Bettencourt, Nuno; Fontes-Carvalho, Ricardo

    2018-06-01

    Left atrial dysfunction in aortic stenosis may precede atrial enlargement and predict the occurrence of atrial fibrillation (AF). To test this hypothesis, we assessed left atrial function and determined its impact on the incidence of AF after aortic valve replacement. A total of 149 severe aortic stenosis patients (74±8.6 years, 51% men) with no prior AF were assessed using speckle-tracking echocardiography. Left atrial function was evaluated using peak atrial longitudinal strain (PALS), peak atrial contraction strain (PACS), and phasic left atrial volumes. The occurrence of AF was monitored in 114 patients from surgery until hospital discharge. In multiple linear regression, PALS and PACS were inversely correlated with left atrial dilation, left ventricular hypertrophy, and diastolic function. Atrial fibrillation occurred in 36 patients within a median time of 3 days [interquartile range, 1-4] after aortic valve replacement. In multiple Cox regression, PALS and PACS were independently associated with the incidence of AF (HR, 0.946; 95%CI, 0.910-0.983; P=.005 and HR, 0.932; 95%CI, 0.883-0.984; P=.011, respectively), even after further adjustment for left atrial dimensions. Both reduced PALS and PACS were associated with the incidence of AF in patients with nondilated left atria (P value for the interaction of PALS with left atrial dimensions=.013). In severe aortic stenosis, left atrial dysfunction predicted the incidence of postoperative AF independently of left atrial dilation, suggesting that speckle-tracking echocardiography before surgery may help in risk stratification, particularly in patients with nondilated left atria. Copyright © 2017 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

  13. pi-Turns: types, systematics and the context of their occurrence in protein structures

    PubMed Central

    Dasgupta, Bhaskar; Chakrabarti, Pinak

    2008-01-01

    Background For a proper understanding of protein structure and folding it is important to know if a polypeptide segment adopts a conformation inherent in the sequence or it depends on the context of its flanking secondary structures. Turns of various lengths have been studied and characterized starting from three-residue γ-turn to six-residue π-turn. The Schellman motif occurring at the C-terminal end of α-helices is a classical example of hydrogen bonded π-turn involving residues at (i) and (i+5) positions. Hydrogen bonded and non-hydrogen bonded β- and α-turns have been identified previously; likewise, a systematic characterization of π-turns would provide valuable insight into turn structures. Results An analysis of protein structures indicates that at least 20% of π-turns occur independent of the Schellman motif. The two categories of π-turns, designated as π-HB and SCH, have been further classified on the basis of backbone conformation and both have AAAa as the major class. They differ in the residue usage at position (i+1), the former having a large preference for Pro that is absent in the latter. As in the case of shorter length β- and α-turns, π-turns have also been identified not only on the basis of the existence of hydrogen bond, but also using the distance between terminal Cα-atoms, and this resulted in a comparable number of non-hydrogen-bonded π-turns (π-NHB). The presence of shorter β- and α-turns within all categories of π-turns, the subtle variations in backbone torsion angles along the turn residues, the location of the turns in the context of tertiary structures have been studied. Conclusion π-turns have been characterized, first using hydrogen bond and the distance between Cα atoms of the terminal residues, and then using backbone torsion angles. While the Schellman motif has a structural role in helix termination, many of the π-HB turns, being located on surface cavities, have functional role and there is also sequence

  14. pi-Turns: types, systematics and the context of their occurrence in protein structures.

    PubMed

    Dasgupta, Bhaskar; Chakrabarti, Pinak

    2008-09-22

    For a proper understanding of protein structure and folding it is important to know if a polypeptide segment adopts a conformation inherent in the sequence or it depends on the context of its flanking secondary structures. Turns of various lengths have been studied and characterized starting from three-residue gamma-turn to six-residue pi-turn. The Schellman motif occurring at the C-terminal end of alpha-helices is a classical example of hydrogen bonded pi-turn involving residues at (i) and (i+5) positions. Hydrogen bonded and non-hydrogen bonded beta- and alpha-turns have been identified previously; likewise, a systematic characterization of pi-turns would provide valuable insight into turn structures. An analysis of protein structures indicates that at least 20% of pi-turns occur independent of the Schellman motif. The two categories of pi-turns, designated as pi-HB and SCH, have been further classified on the basis of backbone conformation and both have AAAa as the major class. They differ in the residue usage at position (i+1), the former having a large preference for Pro that is absent in the latter. As in the case of shorter length beta- and alpha-turns, pi-turns have also been identified not only on the basis of the existence of hydrogen bond, but also using the distance between terminal C alpha-atoms, and this resulted in a comparable number of non-hydrogen-bonded pi-turns (pi-NHB). The presence of shorter beta- and alpha-turns within all categories of pi-turns, the subtle variations in backbone torsion angles along the turn residues, the location of the turns in the context of tertiary structures have been studied. pi-turns have been characterized, first using hydrogen bond and the distance between C alpha atoms of the terminal residues, and then using backbone torsion angles. While the Schellman motif has a structural role in helix termination, many of the pi-HB turns, being located on surface cavities, have functional role and there is also sequence

  15. Topological side-chain classification of beta-turns: ideal motifs for peptidomimetic development.

    PubMed

    Tran, Tran Trung; McKie, Jim; Meutermans, Wim D F; Bourne, Gregory T; Andrews, Peter R; Smythe, Mark L

    2005-08-01

    Beta-turns are important topological motifs for biological recognition of proteins and peptides. Organic molecules that sample the side chain positions of beta-turns have shown broad binding capacity to multiple different receptors, for example benzodiazepines. Beta-turns have traditionally been classified into various types based on the backbone dihedral angles (phi2, psi2, phi3 and psi3). Indeed, 57-68% of beta-turns are currently classified into 8 different backbone families (Type I, Type II, Type I', Type II', Type VIII, Type VIa1, Type VIa2 and Type VIb and Type IV which represents unclassified beta-turns). Although this classification of beta-turns has been useful, the resulting beta-turn types are not ideal for the design of beta-turn mimetics as they do not reflect topological features of the recognition elements, the side chains. To overcome this, we have extracted beta-turns from a data set of non-homologous and high-resolution protein crystal structures. The side chain positions, as defined by C(alpha)-C(beta) vectors, of these turns have been clustered using the kth nearest neighbor clustering and filtered nearest centroid sorting algorithms. Nine clusters were obtained that cluster 90% of the data, and the average intra-cluster RMSD of the four C(alpha)-C(beta) vectors is 0.36. The nine clusters therefore represent the topology of the side chain scaffold architecture of the vast majority of beta-turns. The mean structures of the nine clusters are useful for the development of beta-turn mimetics and as biological descriptors for focusing combinatorial chemistry towards biologically relevant topological space.

  16. Type I and II β-turns prediction using NMR chemical shifts.

    PubMed

    Wang, Ching-Cheng; Lai, Wen-Chung; Chuang, Woei-Jer

    2014-07-01

    A method for predicting type I and II β-turns using nuclear magnetic resonance (NMR) chemical shifts is proposed. Isolated β-turn chemical-shift data were collected from 1,798 protein chains. One-dimensional statistical analyses on chemical-shift data of three classes β-turn (type I, II, and VIII) showed different distributions at four positions, (i) to (i + 3). Considering the central two residues of type I β-turns, the mean values of Cο, Cα, H(N), and N(H) chemical shifts were generally (i + 1) > (i + 2). The mean values of Cβ and Hα chemical shifts were (i + 1) < (i + 2). The distributions of the central two residues in type II and VIII β-turns were also distinguishable by trends of chemical shift values. Two-dimensional cluster analyses on chemical-shift data show positional distributions more clearly. Based on these propensities of chemical shift classified as a function of position, rules were derived using scoring matrices for four consecutive residues to predict type I and II β-turns. The proposed method achieves an overall prediction accuracy of 83.2 and 84.2% with the Matthews correlation coefficient values of 0.317 and 0.632 for type I and II β-turns, indicating that its higher accuracy for type II turn prediction. The results show that it is feasible to use NMR chemical shifts to predict the β-turn types in proteins. The proposed method can be incorporated into other chemical-shift based protein secondary structure prediction methods.

  17. Comparison of left atrial size and function in hypertrophic cardiomyopathy and in Fabry disease with left ventricular hypertrophy.

    PubMed

    Saccheri, María Cristina; Cianciulli, Tomás Francisco; Challapa Licidio, Wilde; Lax, Jorge A; Beck, Martín A; Morita, Luis A; Gagliardi, Juan A

    2018-05-01

    Fabry disease (FD) and hypertrophic cardiomyopathy (HCM) are two diseases with a different pathophysiology, both cause left ventricular hypertrophy (LVH) and myocardial fibrosis. Although remodeling and systolic dysfunction of the left atrium (LA) are associated with atrial fibrillation and stroke in HCM, changes in the size and function of the LA have not been well studied in FD with LVH. The following groups were studied prospectively, and their respective findings compared: 19 patients with non-obstructive HCM (Group I), 20 patients with a diagnosis of Fabry cardiomyopathy (Group II), and 20 normal subjects matched for sex and age (Group III). Left ventricular mass index was measured using Devereux' formula, left atrial volume with Simpson's biplane method and left atrial mechanical function, including strain and strain rate, was measured using the speckle tracking technique. Strain and strain rate of the reservoir were measured during the three phases: reservoir (SR S), passive conduit (SR E) and atrial contraction (SR A). Patients with HCM had a larger left atrial volume than patients with FD (48.16 ± 14.3 mL/m 2 vs 38.9 ± 14.9 mL/m 2 respectively, P < .001), but in both disorders there was a severe decrease in left atrial function: reservoir strain in the apical four-chamber view: 17.47% in HCM vs 22.5% in FD, P = .24), strain rate in the apical chamber view: SR A: -0.80/seconds in HCM vs -1.04/seconds in FD (P = .88), SR S: 0.69/seconds in HCM vs 0.93 in FD (P = .12), SR E: -0.80 seconds in HCM vs -0.97/seconds in FD (P = .18). In this echocardiographic study we used speckle tracking to assess left atrial mechanical function and showed that FD is associated to an atrial cardiomyopathy, affecting the three phasic functions of the LA. Although in patients with HCM left atrial volume is larger than in patients with FD, both disorders exhibit severe decrease in left atrial function. These findings should be considered, given the potentially

  18. Head turning as a prominent motor symptom in status epilepticus.

    PubMed

    Bauer, Gerhard; Broessner, Gregor; Unterberger, Iris; Walser, Gerald; Pfausler, Bettina; Trinka, Eugen

    2008-06-01

    Head and eye turning is frequently observed during seizures. Versions with tonic and/or clonic symptoms can be differentiated from smooth head deviations. Head turning as a prominent symptom of status epilepticus has not previously been reported. We present eight case reports, (7 women/1 man, mean age 41 years, median 41.5, range 10 to 74), of status epilepticus (SE), with head turning as a prominent motor symptom. Six were accompanied by continuous frontal, occipital and temporal ictal epileptiform discharges. Furthermore, two patients had absence status with rhythmic and clonic head versions. While the localizing significance of head turnings in SE is low, in our cases, the direction was away from the discharging hemisphere in all cases of focal SE regardless of whether the turning was classified as version (three cases) or deviation (three cases). In this small series of SE, the classical observation of a patient looking away from the discharging hemisphere is still valid.

  19. Switching handedness: fMRI study of hand motor control in right-handers, left-handers and converted left-handers.

    PubMed

    Grabowska, Anna; Gut, Malgorzata; Binder, Marek; Forsberg, Lars; Rymarczyk, Krystyna; Urbanik, Andrzej

    2012-01-01

    The purpose of this study was to investigate the differences in the brain organization of motor control in left- and right-handers and to study whether early left-to-right handwriting switch changes the cortical representation of finger movements in the left and right hemispheres. Echo-planar MR imaging was performed in 52 subjects: consistent right-handers (RH), consistent left-handers (LH), and subjects who had been forced at an early age to switch their left-hand preferences toward the right side. The scanning was performed during simple (flexion/extension of the index finger) and complex (successive finger-thumb opposition) tasks. Subjects performed the tasks using both the preferred and non-preferred hand. In right-handers, there was a general predominance of left-hemisphere activation relative to right hemisphere activation. In lefthanders this pattern was reversed. The switched subjects showed no such volumetric asymmetry. Increasing levels of complexity of motor activity resulted in an increase in the volume of consistently activated areas and the involvement of the ipsilateral in addition to contralateral activations. In both right- and left-handers, movements of the preferred hand activated mainly the contralateral hemisphere, whereas movements of the non-preferred hand resulted in a more balanced pattern of activation in the two hemispheres, indicating greater involvement of the ipsilateral activations. Overall, this study shows that in both left- and right-handed subjects, the preferred hand is controlled mainly by the hemisphere contralateral to that hand, whereas the non-preferred hand is controlled by both hemispheres. The switched individuals share features of both lefthanders and right-handers regarding their motor control architectures.

  20. Professional Employees Turn to Unions

    ERIC Educational Resources Information Center

    Chamot, Dennis

    1976-01-01

    White-collar and professional employees are increasingly turning to unions to combat their loss of independence as employees of large organizations. Managers should realize that they and professional employees have different viewpoints about job situations and that the current trend toward white-collar unionism is apt to continue. (JG)

  1. Wheelchair caster shimmy and turning resistance.

    PubMed

    Kauzlarich, J J; Bruning, T; Thacker, J G

    1984-07-01

    The equations for wheelchair caster wheel shimmy are presented along with experimental data. The report includes the theory and performance of single wheel casters for a variety of tires, and a new design for wheelchair casters using a grooved dual-tread tire or co-rotating caster wheels. The dual-tread tire was found to significantly inhibit caster shimmy. The turning resistance due to a grooved caster wheel tire with a 1/2-inch groove was found to be 10 percent greater than for an ungrooved caster wheel tire. The analysis includes the methodology and the results of experiments developed to measure the sliding friction turning moment of the wheelchair caster wheel. A number of commercial wheelchair caster wheels were tested and the results for shimmy are presented.

  2. Defining the loop structures in proteins based on composite β-turn mimics.

    PubMed

    Dhar, Jesmita; Chakrabarti, Pinak

    2015-06-01

    Asx- and ω-turns are β-turn mimics, which replace the conventional main-chain hydrogen bonds seen in the latter by those involving the side chains, and both involve three residues. In this paper we analyzed the cases where these turns occur together--side by side, with or without any gap, overlapping and in any order. These composite turns (of length 3-15 residues), occurring at ∼1 per 100 residues, may constitute the full length of many loops, and when the residues in the two component turns overlap or are adjacent to each other, the composite may take well-defined shape. It is thus possible for non-regular regions in protein structure to form local structural motifs, akin to the regular geometrical features exhibited by secondary structures. Composites having the order ω-turns followed by Asx-turns can constitute N-terminal helix capping motif. Ternary composite turns (made up of ω-, Asx- and ST-turns), some with characteristic shape, have also been identified. Delineation of composite turns would help in characterizing loops in protein structures, which often have functional roles. Some sequence patterns seen in composites can be used for their incorporation in protein design. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  3. Modification of impulse generation during piqué turns with increased rotational demands.

    PubMed

    Zaferiou, Antonia M; Wilcox, Rand R; McNitt-Gray, Jill L

    2016-06-01

    During initiation of a piqué turn, a dancer generates impulse to achieve the desired lateral translation and whole-body rotation. The goal of this study was to determine how individuals regulate impulse generation when initiating piqué turns with increased rotational demands. Skilled dancers (n=10) performed single (∼360°) and double (∼720°) piqué turns from a stationary position. Linear and angular impulse generated by the push and turn legs were quantified using ground reaction forces and compared across turn conditions as a group and within a dancer using probability-based statistical methods. The results indicate that as the rotation demands of the piqué turn increased, the net angular impulse generated increased whereas net lateral impulse decreased. Early during turn initiation, the free moment contributed to angular impulse generation. Later during turn initiation, horizontal reaction forces were controlled to generate angular impulse. As rotational demands increased, the moment applied increased primarily from redirection of the horizontal reaction force (RFh) at the push leg and a combination of RFh magnitude and moment arm increases at the turn leg. RFh at each leg were coordinated to limit unwanted net linear impulse. Knowledge of observed subject-specific mechanisms is important to inform the design of turning performance training tools. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Detonation corner turning in vapor-deposited explosives using the micromushroom test

    NASA Astrophysics Data System (ADS)

    Tappan, Alexander S.; Yarrington, Cole D.; Knepper, Robert

    2017-06-01

    Detonation corner turning describes the ability of a detonation wave to propagate into unreacted explosive that is not immediately in the path normal to the wave. The classic example of corner turning is cylindrical and involves a small diameter explosive propagating into a larger diameter explosive as described by Los Alamos' Mushroom test (e.g. (Hill, Seitz et al. 1998)), where corner turning is inferred from optical breakout of the detonation wave. We present a complimentary method to study corner turning in millimeter-scale explosives through the use of vapor deposition to prepare the slab (quasi-2D) analog of the axisymmetric mushroom test. Because the samples are in a slab configuration, optical access to the explosive is excellent and direct imaging of the detonation wave and ``dead zone'' that results during corner turning is possible. Results are compared for explosives that demonstrate a range of behaviors, from pentaerythritol tetranitrate (PETN), which has corner turning properties that are nearly ideal; to HNAB (hexanitroazobenzene), which has corner turning properties that reveal a substantial dead zone. Results are discussed in the context of microstructure and detonation failure thickness.

  5. Diastolic function of the nonfilling human left ventricle.

    PubMed

    Paulus, W J; Vantrimpont, P J; Rousseau, M F

    1992-12-01

    To investigate an early-diastolic left ventricular suction effect in humans, tip-micromanometer left ventricular pressure recordings were obtained in patients with mitral stenosis at the time of balloon inflations during percutaneous mitral valvuloplasty performed with a self-positioning Inoue balloon, which fits tightly in the mitral orifice. When mitral inflow was impeded in anesthetized dogs, left ventricular pressure decayed to a negative asymptote value. This negative asymptote value was consistent with an early diastolic suction effect. Tip-micromanometer left ventricular pressure recordings were obtained in 23 patients with symptomatic mitral stenosis at the time of balloon inflations during percutaneous mitral valvuloplasty performed with a self-positioning Inoue balloon. The left ventricular diastolic asymptote pressure (P(asy)) was determined in 47 nonfilling beats with a sufficiently long (greater than 200 ms) diastolic time interval (that is, the interval from minimal first derivative of left ventricular pressure to left ventricular end-diastolic pressure) and equaled 2 +/- 3 mm Hg for beats with normal intraventricular conduction and 3 +/- 2 mm Hg for beats with aberrant intraventricular conduction. Left ventricular angiography was performed in five patients during the first inflation of the Inoue balloon at the time of complete balloon expansion. Left ventricular end-diastolic volume of the nonfilling beats averaged 38 +/- 14 ml and was comparable to the left ventricular end-systolic volume (39 +/- 19 ml) measured during baseline angiography before mitral valvuloplasty. Time constants of left ventricular pressure decay were calculated on 21 nonfilling beats with a diastolic time interval greater than 200 ms, normal intraventricular conduction and peak left ventricular pressure greater than 50 mm Hg. Time constants (T0 and TBF) derived from an exponential curve fit with zero asymptote pressure and with a best-fit asymptote pressure were compared with a

  6. CT derived left atrial size identifies left heart disease in suspected pulmonary hypertension: Derivation and validation of predictive thresholds.

    PubMed

    Currie, Benjamin J; Johns, Chris; Chin, Matthew; Charalampopolous, Thanos; Elliot, Charlie A; Garg, Pankaj; Rajaram, Smitha; Hill, Catherine; Wild, Jim W; Condliffe, Robin A; Kiely, David G; Swift, Andy J

    2018-06-01

    Patients with pulmonary hypertension due to left heart disease (PH-LHD) have overlapping clinical features with pulmonary arterial hypertension making diagnosis reliant on right heart catheterization (RHC). This study aimed to investigate computed tomography pulmonary angiography (CTPA) derived cardiopulmonary structural metrics, in comparison to magnetic resonance imaging (MRI) for the diagnosis of left heart disease in patients with suspected pulmonary hypertension. Patients with suspected pulmonary hypertension who underwent CTPA, MRI and RHC were identified. Measurements of the cardiac chambers and vessels were recorded from CTPA and MRI. The diagnostic thresholds of individual measurements to detect elevated pulmonary arterial wedge pressure (PAWP) were identified in a derivation cohort (n = 235). Individual CT and MRI derived metrics were tested in validation cohort (n = 211). 446 patients, of which 88 had left heart disease. Left atrial area was a strong predictor of elevated PAWP>15 mm Hg and PAWP>18 mm Hg, area under curve (AUC) 0.854, and AUC 0.873 respectively. Similar accuracy was also identified for MRI derived LA volume, AUC 0.852 and AUC 0.878 for PAWP > 15 and 18 mm Hg, respectively. Left atrial area of 26.8 cm 2 and 30.0 cm 2 were optimal specific thresholds for identification of PAWP > 15 and 18 mm Hg, had sensitivity of 60%/53% and specificity 89%/94%, respectively in a validation cohort. CTPA and MRI derived left atrial size identifies left heart disease in suspected pulmonary hypertension with high specificity. The proposed diagnostic thresholds for elevated left atrial area on routine CTPA may be a useful to indicate the diagnosis of left heart disease in suspected pulmonary hypertension. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

  7. A novel method for calculating the energy cost of turning during running

    PubMed Central

    Hatamoto, Yoichi; Yamada, Yosuke; Fujii, Tatsuya; Higaki, Yasuki; Kiyonaga, Akira; Tanaka, Hiroaki

    2013-01-01

    Although changes of direction are one of the essential locomotor patterns in ball sports, the physiological demand of turning during running has not been previously investigated. We proposed a novel approach by which to evaluate the physiological demand of turning. The purposes of this study were to establish a method of measuring the energy expenditure (EE) of a 180° turn during running and to investigate the effect of two different running speeds on the EE of a 180° turn. Eleven young, male participants performed measurement sessions at two different running speeds (4.3 and 5.4 km/hour). Each measurement session consisted of five trials, and each trial had a different frequency of turns. At both running speeds, as the turn frequency increased the gross oxygen consumption (V·O2) also increased linearly (4.3 km/hour, r = 0.973; 5.4 km/hour, r = 0.996). The V·O2 of a turn at 5.4 km/hour (0.55 [SD 0.09] mL/kg) was higher than at 4.3 km/hour (0.34 [SD 0.13] mL/kg) (P < 0.001). We conclude that the gross V·O2 of running at a fixed speed with turns is proportional to turn frequency and that the EE of a turn is different at different running speeds. The Different Frequency Accumulation Method is a useful tool for assessing the physiological demands of complex locomotor activity. PMID:24379716

  8. Left ventricular lipoma with pseudoaneurysm-like appearance.

    PubMed

    Kawarai, Shun-ichi; Yaginuma, Gen-ya; Abe, Kazuo; Hamasaki, Azumi; Ishikawa, Kazunori; Tanaka, Daizo

    2010-06-01

    We describe an extremely rare cardiac lipoma, with electrocardiographic changes in ST segments and T waves, suggesting ischemic heart disease. The abnormal electrocardiogram was identified during a routine physical examination of an asymptomatic 57-year-old man. Coronary angiography showed no stenotic or occlusive lesions in the coronary arteries except that the left anterior descending artery followed a winding course in the apical region. Left ventriculography revealed a pseudoaneurysm-like mass around the apical portion. Computed tomography and magnetic resonance imaging revealed a cardiac lipoma that communicated with the left ventricle and resembled a pseudoaneurysm. After complete resection of the lipoma and left ventricle patch plasty, the postoperative course was uneventful. Histologically, the tumor was an intramyocardiac lipoma with no evidence of malignancy. To our knowledge, we are the first to describe an intramyocardiac lipoma resembling a left ventricle pseudoaneurysm.

  9. Wrong Turn on School Reform

    ERIC Educational Resources Information Center

    Hess, Frederick M.; Petrilli, Michael J.

    2009-01-01

    In the run-up to the 2000 presidential election, candidate George W. Bush and his advisors made a strategic decision to appropriate educational rhetoric generally associated with Democrats and the left. This decision helped Bush present himself as "different kind of Republican" and a "compassionate conservative" and to…

  10. [Surgical angioplasty of the left main coronary artery].

    PubMed

    Vranes, Mile; Velinović, Milos; Kocica, Mladen; Mikić, Aleksandar; Velimirović, Dusan; Djukić, Petar

    2010-01-01

    The conventional treatment for isolated stenosis of the left main coronary artery is bypass surgery (myocardial revascularization). However, the process of atherosclerosis is not arrested by myocardial revascularization and it will lead to the occlusion of the left main coronary artery. Revascularization will establish retrograde perfusion for 50-70% of the myocardium of the left ventricle. Direct surgical angioplasty of the left main coronary artery enables normal physiological perfusion of the whole myocardium and better myocardial function. The aim of our study is to point out a new surgical approach of treating left main coronary artery stenosis. Between October 2002 and October 2003, direct surgical angioplasty of the main left coronary artery was performed on three patients with isolated stenosis of the left main coronary artery using the anterior approach and the pericardium as a patch. The procedure was performed under total endotracheal anaesthesia and standard cardiopulmonary circulation, moderate hypothermia, anterograde St. Tomas cardioplegia and local cooling. Patients were followed clinically, echocardiographically and by load-tests. All three patients were without complications. In postoperative follow-up (54-68 months) neither angina pectoris nor electrocardiographically registered ischaemic changes were found. Load-tests performed every six months on all three patients were negative. Surgical angioplasty of isolated stenosis of the left main coronary artery is a preferred method for treating this type of coronary disease. Contraindications for this type of treatment are stenosis of the left main coronary artery with bifurcation and advanced calcification of the left main coronary artery.

  11. Support vector machines for prediction and analysis of beta and gamma-turns in proteins.

    PubMed

    Pham, Tho Hoan; Satou, Kenji; Ho, Tu Bao

    2005-04-01

    Tight turns have long been recognized as one of the three important features of proteins, together with alpha-helix and beta-sheet. Tight turns play an important role in globular proteins from both the structural and functional points of view. More than 90% tight turns are beta-turns and most of the rest are gamma-turns. Analysis and prediction of beta-turns and gamma-turns is very useful for design of new molecules such as drugs, pesticides, and antigens. In this paper we investigated two aspects of applying support vector machine (SVM), a promising machine learning method for bioinformatics, to prediction and analysis of beta-turns and gamma-turns. First, we developed two SVM-based methods, called BTSVM and GTSVM, which predict beta-turns and gamma-turns in a protein from its sequence. When compared with other methods, BTSVM has a superior performance and GTSVM is competitive. Second, we used SVMs with a linear kernel to estimate the support of amino acids for the formation of beta-turns and gamma-turns depending on their position in a protein. Our analysis results are more comprehensive and easier to use than the previous results in designing turns in proteins.

  12. Crack turning in integrally stiffened aircraft structures

    NASA Astrophysics Data System (ADS)

    Pettit, Richard Glen

    Current emphasis in the aircraft industry toward reducing manufacturing cost has created a renewed interest in integrally stiffened structures. Crack turning has been identified as an approach to improve the damage tolerance and fail-safety of this class of structures. A desired behavior is for skin cracks to turn before reaching a stiffener, instead of growing straight through. A crack in a pressurized fuselage encounters high T-stress as it nears the stiffener---a condition favorable to crack turning. Also, the tear resistance of aluminum alloys typically varies with crack orientation, a form of anisotropy that can influence the crack path. The present work addresses these issues with a study of crack turning in two-dimensions, including the effects of both T-stress and fracture anisotropy. Both effects are shown to have relation to the process zone size, an interaction that is central to this study. Following an introduction to the problem, the T-stress effect is studied for a slightly curved semi-infinite crack with a cohesive process zone, yielding a closed form expression for the future crack path in an infinite medium. For a given initial crack tip curvature and tensile T-stress, the crack path instability is found to increase with process zone size. Fracture orthotropy is treated using a simple function to interpolate between the two principal fracture resistance values in two-dimensions. An extension to three-dimensions interpolates between the six principal values of fracture resistance. Also discussed is the transition between mode I and mode II fracture in metals. For isotropic materials, there is evidence that the crack seeks out a direction of either local symmetry (pure mode I) or local asymmetry (pure mode II) growth. For orthotropic materials the favored states are not pure modal, and have mode mixity that is a function of crack orientation. Drawing upon these principles, two crack turning prediction approaches are extended to include fracture

  13. Prediction of beta-turns and beta-turn types by a novel bidirectional Elman-type recurrent neural network with multiple output layers (MOLEBRNN).

    PubMed

    Kirschner, Andreas; Frishman, Dmitrij

    2008-10-01

    Prediction of beta-turns from amino acid sequences has long been recognized as an important problem in structural bioinformatics due to their frequent occurrence as well as their structural and functional significance. Because various structural features of proteins are intercorrelated, secondary structure information has been often employed as an additional input for machine learning algorithms while predicting beta-turns. Here we present a novel bidirectional Elman-type recurrent neural network with multiple output layers (MOLEBRNN) capable of predicting multiple mutually dependent structural motifs and demonstrate its efficiency in recognizing three aspects of protein structure: beta-turns, beta-turn types, and secondary structure. The advantage of our method compared to other predictors is that it does not require any external input except for sequence profiles because interdependencies between different structural features are taken into account implicitly during the learning process. In a sevenfold cross-validation experiment on a standard test dataset our method exhibits the total prediction accuracy of 77.9% and the Mathew's Correlation Coefficient of 0.45, the highest performance reported so far. It also outperforms other known methods in delineating individual turn types. We demonstrate how simultaneous prediction of multiple targets influences prediction performance on single targets. The MOLEBRNN presented here is a generic method applicable in a variety of research fields where multiple mutually depending target classes need to be predicted. http://webclu.bio.wzw.tum.de/predator-web/.

  14. Alternative Fuels Data Center: quasar energy group Turns Organic Waste into

    Science.gov Websites

    Renewable Energy in Ohio quasar energy group Turns Organic Waste into Renewable Energy in Ohio to someone by E-mail Share Alternative Fuels Data Center: quasar energy group Turns Organic Waste group Turns Organic Waste into Renewable Energy in Ohio on Twitter Bookmark Alternative Fuels Data

  15. Anticipatory detection of turning in humans for intuitive control of robotic mobility assistance.

    PubMed

    Farkhatdinov, Ildar; Roehri, Nicolas; Burdet, Etienne

    2017-09-26

    Many wearable lower-limb robots for walking assistance have been developed in recent years. However, it remains unclear how they can be commanded in an intuitive and efficient way by their user. In particular, providing robotic assistance to neurologically impaired individuals in turning remains a significant challenge. The control should be safe to the users and their environment, yet yield sufficient performance and enable natural human-machine interaction. Here, we propose using the head and trunk anticipatory behaviour in order to detect the intention to turn in a natural, non-intrusive way, and use it for triggering turning movement in a robot for walking assistance. We therefore study head and trunk orientation during locomotion of healthy adults, and investigate upper body anticipatory behaviour during turning. The collected walking and turning kinematics data are clustered using the k-means algorithm and cross-validation tests and k-nearest neighbours method are used to evaluate the performance of turning detection during locomotion. Tests with seven subjects exhibited accurate turning detection. Head anticipated turning by more than 400-500 ms in average across all subjects. Overall, the proposed method detected turning 300 ms after its initiation and 1230 ms before the turning movement was completed. Using head anticipatory behaviour enabled to detect turning faster by about 100 ms, compared to turning detection using only pelvis orientation measurements. Finally, it was demonstrated that the proposed turning detection can improve the quality of human-robot interaction by improving the control accuracy and transparency.

  16. Expanding the peptide beta-turn in alphagamma hybrid sequences: 12 atom hydrogen bonded helical and hairpin turns.

    PubMed

    Chatterjee, Sunanda; Vasudev, Prema G; Raghothama, Srinivasarao; Ramakrishnan, Chandrasekharan; Shamala, Narayanaswamy; Balaram, Padmanabhan

    2009-04-29

    Hybrid peptide segments containing contiguous alpha and gamma amino acid residues can form C(12) hydrogen bonded turns which may be considered as backbone expanded analogues of C(10) (beta-turns) found in alphaalpha segments. Exploration of the regular hydrogen bonded conformations accessible for hybrid alphagamma sequences is facilitated by the use of a stereochemically constrained gamma amino acid residue gabapentin (1-aminomethylcyclohexaneacetic acid, Gpn), in which the two torsion angles about C(gamma)-C(beta) (theta(1)) and C(beta)-C(alpha) (theta(2)) are predominantly restricted to gauche conformations. The crystal structures of the octapeptides Boc-Gpn-Aib-Gpn-Aib-Gpn-Aib-Gpn-Aib-OMe (1) and Boc-Leu-Phe-Val-Aib-Gpn-Leu-Phe-Val-OMe (2) reveal two distinct conformations for the Aib-Gpn segment. Peptide 1 forms a continuous helix over the Aib(2)-Aib(6) segment, while the peptide 2 forms a beta-hairpin structure stabilized by four cross-strand hydrogen bonds with the Aib-Gpn segment forming a nonhelical C(12) turn. The robustness of the helix in peptide 1 in solution is demonstrated by NMR methods. Peptide 2 is conformationally fragile in solution with evidence of beta-hairpin conformations being obtained in methanol. Theoretical calculations permit delineation of the various C(12) hydrogen bonded structures which are energetically feasible in alphagamma and gammaalpha sequences.

  17. BetaTPred: prediction of beta-TURNS in a protein using statistical algorithms.

    PubMed

    Kaur, Harpreet; Raghava, G P S

    2002-03-01

    beta-turns play an important role from a structural and functional point of view. beta-turns are the most common type of non-repetitive structures in proteins and comprise on average, 25% of the residues. In the past numerous methods have been developed to predict beta-turns in a protein. Most of these prediction methods are based on statistical approaches. In order to utilize the full potential of these methods, there is a need to develop a web server. This paper describes a web server called BetaTPred, developed for predicting beta-TURNS in a protein from its amino acid sequence. BetaTPred allows the user to predict turns in a protein using existing statistical algorithms. It also allows to predict different types of beta-TURNS e.g. type I, I', II, II', VI, VIII and non-specific. This server assists the users in predicting the consensus beta-TURNS in a protein. The server is accessible from http://imtech.res.in/raghava/betatpred/

  18. Effect of stern hull shape on turning circle of ships

    NASA Astrophysics Data System (ADS)

    Jaswar, Maimun, A.; Wahid, M. A.; Priyanto, A.; Zamani, Pauzi, Saman

    2012-06-01

    Many factors such as: stern hull shape, length, draught, trim, propulsion system and external forces affecting the drift angle influence rate of turn and size of turning circle of ships. This paper discusses turning circle characteristics of U and V stern hull shape of Very Large Crude Oil Carrier (VLCC) ships. The ships have same principal dimension such as length, beam, and draught. The turning circle characteristics of the VLCC ships are simulated at 35 degree of rudder angle. In the analysis, firstly, turning circle performance of U-type VLCC ship is simulated. In the simulation, initial ship speed is determined using given power and rpm. Hydrodynamic derivatives coefficients are determined by including effect of fullness of aft run. Using the obtained, speed and hydrodynamic coefficients, force and moment acting on hull, force and moment induced by propeller, force and moment induced by rudder are determined. Finally, ship trajectory, ratio of speed, yaw angle and drift angle are determined. Results of simulation results of the VLCC ship are compared with the experimental one as validation. Using the same method, V-type VLCC is simulated and the simulation results are compared with U-type VLCC ship. Results shows the turning circle of U-type is larger than V-type due to effect stern hul results of simulation are.

  19. Measurement of signal use and vehicle turns as indication of driver cognition.

    PubMed

    Wallace, Bruce; Goubran, Rafik; Knoefel, Frank

    2014-01-01

    This paper uses data analytics to provide a method for the measurement of a key driving task, turn signal usage as a measure of an automatic over-learned cognitive function drivers. The paper augments previously reported more complex executive function cognition measures by proposing an algorithm that analyzes dashboard video to detect turn indicator use with 100% accuracy without any false positives. The paper proposes two algorithms that determine the actual turns made on a trip. The first through analysis of GPS location traces for the vehicle, locating 73% of the turns made with a very low false positive rate of 3%. A second algorithm uses GIS tools to retroactively create turn by turn directions. Fusion of GIS and GPS information raises performance to 77%. The paper presents the algorithm required to measure signal use for actual turns by realigning the 0.2Hz GPS data, 30fps video and GIS turn events. The result is a measure that can be tracked over time and changes in the driver's performance can result in alerts to the driver, caregivers or clinicians as indication of cognitive change. A lack of decline can also be shared as reassurance.

  20. [Surgical treatment of cancer of the left colon. True left hemicolectomy or segmental colectomy?].

    PubMed

    Rouffet, F; Fontaine, M; Zerbib, J J; Mathon, C

    1988-12-01

    Non-metastatic cancer of the left colon is still an exclusively surgical problem in 1988. The problem is to determine which type of colectomy should be performed: either a true left hemicolectomy, a long but apparently oncologically satisfactory operation, or segmental colectomy. A recent study by A.R.C. reported the same 5-year survival for these two types of operation with essentially identical postoperative mortality and morbidity. This conclusion confirms that of many studies published on this subject.

  1. Analysis of the lateral push-off in the freestyle flip turn.

    PubMed

    Araujo, Luciana; Pereira, Suzana; Gatti, Roberta; Freitas, Elinai; Jacomel, Gabriel; Roesler, Helio; Villas-Boas, Joao

    2010-09-01

    The aim of this study was to examine the contact phase during the lateral push-off in the turn of front crawl swimming to determine which biomechanical variables (maximum normalized peak force, contact time, impulse, angle of knee flexion, and total turn time within 15 m) contribute to the performance of this turn technique. Thirty-four swimmers of state, national, and international competitive standard participated in the study. For data collection, the following equipment was used: an underwater force platform, a 30-Hz VHS video camera, and a MiniDv digital camera within an underwater box. Data are expressed as descriptive statistics. Inferential analyses were performed using Pearson's correlation and multiple linear regressions. All variables studied had a significant relationship with turn performance. We conclude that a turn executed with a knee flexion angle of between 100° and 120° provides optimum peak forces to generate impulses that allow the swimmer to lose less time in the turn without the need for an excessive force application and with less energy lost.

  2. Turning Points in Even Start Programs. Occasional Paper #4.

    ERIC Educational Resources Information Center

    Rasinski, Timothy; Padak, Nancy

    To investigate the initial experiences of the various Even Start programs, a project developed a survey that was sent to program coordinators in Ohio. It asked open-ended questions to get descriptions and perceptions of situations that preceded turning point events and the turning point events themselves. Data from eight programs highlighted their…

  3. Development of warrants for installation of dual right-turn lanes at signalized intersections.

    DOT National Transportation Integrated Search

    2012-04-01

    Right-turn lanes provide space for the deceleration and storage of right-turn vehicles, and separate turning vehicles : from through movements. Dual right-turn lanes are increasingly used at urban intersections primarily for two : reasons: (1) to acc...

  4. Accuracy of ECG indices for diagnosis of left ventricular hypertrophy in people >65 years: results from the ActiFE study.

    PubMed

    Laszlo, Roman; Kunz, Katia; Dallmeier, Dhayana; Klenk, Jochen; Denkinger, Michael; Koenig, Wolfgang; Rothenbacher, Dietrich; Steinacker, Juergen Michael

    2017-10-01

    The detection of left ventricular hypertrophy (LVH) is still a common objective of electrocardiography (ECG) in clinical practice. The aim of our study was to evaluate the accuracy of LVH ECG indices in people older than 65 recruited from a population-based cohort (ActiFE-Ulm study). In 432 subjects (mean age 76.2 ± 5.5 years, 51% male), left ventricular mass was echocardiographically determined (Devereux formula) and indexed (LVMI) to body surface area. Several LVH ECG indices (Lewis voltage, Gubner-Ungerleider voltage, Sokolow-Lyon voltage/product, Cornell voltage/product) were calculated with the help of resting ECG data and compared with the echocardiographic assessment. Despite echocardiographic signs of LVH [LVMI > 115 (♂) or >95 g/m 2 (♀)] in 47.5% of all subjects, diagnostic performance of all ECG indices was generally low. Magnitude of all LVH-indices was mainly predicted by frontal QRS axis in multivariate linear regression analysis. In comparison with the literature data from younger subjects, average frontal QRS axis turned counterclockwise. Most probably, age-related counterclockwise turn of frontal QRS axis is mainly explanatory for the decreased magnitude of LVH ECG indices and consecutive worse diagnostic performance of these indices in the elderly. ECG indices for detection of LVH have insufficient predictive values in geriatric subjects and should therefore not be used clinically for this purpose. Nevertheless, due to its established relevancy in cardiac risk stratification in this age group, usage of some established ECG indices might keep its significance even in the age of modern cardiac imaging.

  5. Left neglect dyslexia: Perseveration and reading error types.

    PubMed

    Ronchi, Roberta; Algeri, Lorella; Chiapella, Laura; Gallucci, Marcello; Spada, Maria Simonetta; Vallar, Giuseppe

    2016-08-01

    Right-brain-damaged patients may show a reading disorder termed neglect dyslexia. Patients with left neglect dyslexia omit letters on the left-hand-side (the beginning, when reading left-to-right) part of the letter string, substitute them with other letters, and add letters to the left of the string. The aim of this study was to investigate the pattern of association, if any, between error types in patients with left neglect dyslexia and recurrent perseveration (a productive visuo-motor deficit characterized by addition of marks) in target cancellation. Specifically, we aimed at assessing whether different productive symptoms (relative to the reading and the visuo-motor domains) could be associated in patients with left spatial neglect. Fifty-four right-brain-damaged patients took part in the study: 50 out of the 54 patients showed left spatial neglect, with 27 of them also exhibiting left neglect dyslexia. Neglect dyslexic patients who showed perseveration produced mainly substitution neglect errors in reading. Conversely, omissions were the prevailing reading error pattern in neglect dyslexic patients without perseveration. Addition reading errors were much infrequent. Different functional pathological mechanisms may underlie omission and substitution reading errors committed by right-brain-damaged patients with left neglect dyslexia. One such mechanism, involving the defective stopping of inappropriate responses, may contribute to both recurrent perseveration in target cancellation, and substitution errors in reading. Productive pathological phenomena, together with deficits of spatial attention to events taking place on the left-hand-side of space, shape the manifestations of neglect dyslexia, and, more generally, of spatial neglect. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Assessment of electrocardiographic criteria of left atrial enlargement.

    PubMed

    Batra, Mahesh Kumar; Khan, Atif; Farooq, Fawad; Masood, Tariq; Karim, Musa

    2018-05-01

    Background Left atrial enlargement is considered to be a robust, strong, and widely acceptable indicator of cardiovascular outcomes. Echocardiography is the gold standard for measurement of left atrial size, but electrocardiography can be simple, cost-effective, and noninvasive in clinical practice. This study was undertaken to assess the diagnostic accuracy of an established electrocardiographic criterion for left atrial enlargement, taking 2-dimensional echocardiography as the gold-standard technique. Methods A cross-sectional study was conducted on 146 consecutively selected patients with the complaints of dyspnea and palpitation and with a murmur detected on clinical examination, from September 10, 2016 to February 10, 2017. Electrocardiography and echocardiography were performed in all patients. Patients with a negative P wave terminal force in lead V 1  > 40 ms·mm on electrocardiography or left atrial dimension > 40 mm on echocardiography were classified as having left atrial enlargement. Sensitivity and specificity were calculated to assess the diagnostic accuracy. Results Taking 2-dimensional echocardiography as the gold-standard technique, electrocardiography correctly diagnosed 68 patients as positive for left atrial enlargement and 12 as negative. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of electrocardiography for left atrial enlargement were 54.4%, 57.1%, 88.3%, 17.4%, and 54.8%, respectively. Conclusion The electrocardiogram appears to be a reasonable indicator of left atrial enlargement. In case of nonavailability of echocardiography, electrocardiography can be used for diagnosis of left atrial enlargement.

  7. Congenital aneurysm of both left ventricle and left atrium.

    PubMed

    Halas, Ryan F; Schmehil, Christopher J; Ten Eyck, Gary R; Loker, James L

    2018-01-01

    This is a case of both congenital left ventricular (LV) free wall submitral aneurysm and left atrial appendage aneurysm with 6 years of clinical follow-up. Each lesion is a rare entity, and to the best of our knowledge, this is the first case in medical literature of both lesions occurring in the same patient, raising the likelihood of a common etiology. The workup was initiated in the third trimester of fetal life with irregular heart rate and abnormal fetal ultrasound and echocardiogram at that time. The patient required emergent atrial appendage plication due to blood clot formation and suffered from multiple other complications including ventricular ectopy and surgically induced pseudoaneurysm. Follow-up interval echocardiograms have revealed continued good LV function with persistent LV aneurysm. In review of the case, there were several potential in utero causes including maternal viral upper respiratory infection and bacteriuria with exposure to amoxicillin. These as well as other considerations are discussed along with a brief review of these rare lesions, usual presentation, and known associations.

  8. Left hemisphere predominance of pilocarpine-induced rat epileptiform discharges

    PubMed Central

    2009-01-01

    Background The left cerebral hemisphere predominance in human focal epilepsy has been observed in a few studies, however, there is no related systematic study in epileptic animal on hemisphere predominance. The main goal of this paper is to observe if the epileptiform discharges (EDs) of Pilocarpine-induced epileptic rats could present difference between left hemisphere and right hemisphere or not. Methods The electrocorticogram (ECoG) and electrohippocampogram (EHG) from Pilocarpine-induced epileptic rats were recorded and analyzed using Synchronization likelihood (SL) in order to determine the synchronization relation between different brain regions, then visual check and cross-correlation analysis were adopted to evaluate if the EDs were originated more frequently from the left hemisphere than the right hemisphere. Results The data show that the synchronization between left-EHG and right-EHG, left-ECoG and left-EHG, right-ECoG and right-EHG, left-ECoG and right-ECoG, are significantly strengthened after the brain functional state transforms from non-epileptiform discharges to continuous-epileptiform discharges(p < 0.05). When the state transforms from continuous EDs to periodic EDs, the synchronization is significantly weakened between left-ECoG and left-EHG, left-EHG and right-EHG (p < 0.05). Visual check and the time delay (τ) based cross-correlation analysis finds that 10 out of 13 EDs have a left predominance (77%) and 3 out of 13 EDs are right predominance (23%). Conclusion The results suggest that the left hemisphere may be more prone to EDs in the Pilocarpine-induced rat epilepsy model and implicate that the left hemisphere might play an important role in epilepsy states transition. PMID:19948024

  9. Anatomy of the left atrium for interventional electrophysiologists.

    PubMed

    Ho, Siew Yen; McCarthy, Karen P

    2010-05-01

    Increasingly, interventional procedures require accessing the left atrium from the inside of the heart as well as from the pericardial space. The right phrenic nerve running along the fibrous pericardium is close to the atrial insertion of the right superior pulmonary vein while the left phrenic nerve passes over the left atrial appendage. Posteriorly, the esophagus descends adjacent to the fibrous pericardium covering the posterior and postero-inferior walls of the left atrium. The component parts of the left atrium are reviewed with emphasis on the structure of the atrial septum, the left atrial ridge, the mitral isthmus, and the left atrial walls. Although the atrial walls are mainly smooth, pits and crevices are common in the region of the mitral isthmus and the vicinity of the os of the atrial appendage. The muscular rim around the valve of the oval fossa delimits the extent of the true atrial septum. Interatrial muscular connections exist at the septum, along Bachmann's bundle and also at the muscular sleeves of the coronary sinus and pulmonary veins. Anatomical features relevant to interventional electrophysiologists are highlighted.

  10. Left ventricular function before and after kidney transplantation.

    PubMed

    Omran, Mohammad T; Khakpour, Somayeh; Oliaie, Farshid

    2009-06-01

    To evaluate left ventricular function by echocardiography before and after kidney transplantation (KT). This analytical study included 50 patients that had successful KT in Shahid Beheshti Hospital, Babol, Iran from October 2005 to December 2007. The echocardiography study was performed by one cardiologist before and at least 3 months after KT. Data were analyzed by SPSS, and a p<0.05 was considered statistically significant. The mean age of patients was 33.94 +/- 11.66 years, 66% were male and 56% less than 45 years old. The ejection fraction and stroke volume after KT increased, however, the left ventricular end diastolic volume, left ventricular end systolic volume, left ventricular end systolic dimension, and left ventricular end diastolic diameter decreased. In patients with end stage renal disease, successful kidney transplantation could improve the function of the left ventricle.

  11. Left heart catheterization

    MedlinePlus

    Catheterization - left heart ... to help guide the catheters up into your heart and arteries. Dye (sometimes called "contrast") will be ... in the blood vessels that lead to your heart. The catheter is then moved through the aortic ...

  12. Turning Point Instabilities for Relativistic Stars and Black Holes

    NASA Astrophysics Data System (ADS)

    Schiffrin, Joshua; Wald, Robert

    2014-03-01

    In the light of recent results relating dynamic and thermodynamic stability of relativistic stars and black holes, we re-examine the relationship between ``turning points''--i.e., extrema of thermodynamic variables along a one-parameter family of solutions--and instabilities. We give a proof of Sorkin's general result--showing the existence of a thermodynamic instability on one side of a turning point--that does not rely on heuristic arguments involving infinite dimensional manifold structure. We use the turning point results to prove the existence of a dynamic instability of black rings in 5 spacetime dimensions in the region where cJ > 0 , in agreement with a result of Figueras, Murata, and Reall.

  13. Turning point instabilities for relativistic stars and black holes

    NASA Astrophysics Data System (ADS)

    Schiffrin, Joshua S.; Wald, Robert M.

    2014-02-01

    In the light of recent results relating dynamic and thermodynamic stability of relativistic stars and black holes, we re-examine the relationship between ‘turning points’—i.e., extrema of thermodynamic variables along a 1-parameter family of solutions—and instabilities. We give a proof of Sorkin’s general result—showing the existence of a thermodynamic instability on one side of a turning point—that does not rely on heuristic arguments involving infinite-dimensional manifold structure. We use the turning point results to prove the existence of a dynamic instability of black rings in five spacetime dimensions in the region where cJ > 0, in agreement with a result of Figueras, Murata and Reall. Communicated by H Reall

  14. Diamond turning of glass

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

    Blackley, W.S.; Scattergood, R.O.

    A new research initiative will be undertaken to investigate the critical cutting depth concepts for single point diamond turning of brittle, amorphous materials. Inorganic glasses and a brittle, thermoset polymer (organic glass) are the principal candidate materials. Interrupted cutting tests similar to those done in earlier research are Ge and Si crystals will be made to obtain critical depth values as a function of machining parameters. The results will provide systematic data with which to assess machining performance on glasses and amorphous materials

  15. Optical spectroscopic elucidation of beta-turns in disulfide bridged cyclic tetrapeptides.

    PubMed

    Borics, Attila; Murphy, Richard F; Lovas, Sándor

    2007-01-01

    Vibrational circular dichroism (VCD) spectroscopic features of type II beta-turns were characterized previously, but, criteria for differentiation between beta-turn types had not been established yet. Model tetrapeptides, cyclized through a disulfide bridge, were designed on the basis of previous experimental results and the observed incidence of amino acid residues in the i + 1 and i + 2 positions in beta-turns, to determine the features of VCD spectra of type I and II beta-turns. The results were correlated with electronic circular dichroism (ECD) spectra and VCD spectra calculated from conformational data obtained by molecular dynamics (MD) simulations. All cyclic tetrapeptides yielded VCD signals with a higher frequency negative and a lower frequency positive couplet with negative lobes overlapping. MD simulations confirmed the conformational homogeneity of these peptides in solution. Comparison with ECD spectroscopy, MD, and quantum chemical calculation results suggested that the low frequency component of VCD spectra originating from the tertiary amide vibrations could be used to distinguish between types of beta-turn structures. On the basis of this observation, VCD spectroscopic features of type II and VIII beta-turns and ECD spectroscopic properties of a type VIII beta-turn were suggested. The need for independent experimental as well as theoretical investigations to obtain decisive conformational information was recognized. Copyright 2006 Wiley Periodicals, Inc.

  16. Median u-turn intersection : informational guide.

    DOT National Transportation Integrated Search

    2014-08-01

    This document provides information and guidance on Median U-Turn (MUT) intersections, resulting in designs suitable for a : variety of typical conditions commonly found in the United States. To the extent possible, the guide provides information on t...

  17. Effects of turn region treatments on pressure loss through sharp 180-degree bends

    NASA Astrophysics Data System (ADS)

    Plevich, C. W.; Metzger, D. E.

    An experimental study was conducted to evaluate the effect of geometric turn region inserts on pressure losses for flow through sharp 180-degree channel turns typical of internal cooling passages in gas turbine engine airfoils. The experiments were conducted in a rectangular cross-sectioned channel with 90-degree transverse rib roughening in both inlet and outlet legs, starting with completely smooth turn regions and progressing through various modifications including corner fillets, radial ribs, and turning vanes. The results show that modifications to the turn region geometry, particularly the inclusion of a single semi-circular turning vane, significantly reduce the pressure losses associated with coolant flows through sharp 180-degree turns and therefore can result in increased coolant flow for a given coolant supply pressure.

  18. Long-term results after left ventricular aneurysmectomy.

    PubMed Central

    Otterstad, J E; Christensen, O; Levorstad, K; Nitter-Hauge, S

    1981-01-01

    Twenty-six patients (21 men and five women) with a mean age of 54.8 years have been reinvestigated nine to 62 months (mean 29.7) after left ventricular aneurysmectomy. Preoperatively left ventricular angiography disclosed an anterior aneurysm in all cases, which was large in 15 (57%) and small to medium in 11 (42%). At follow-up a large residual aneurysm was found in five (19%), a small to medium one in 13 (50%), and akinesia without aneurysm in eight (31%). The sum of ST elevation (sigma ST) in praecordial leads in the electrocardiogram was reduced from a mean value of 11.2 mm to 7.7 mm. In no patient did ST segments return to normal after operation. Preoperatively, mean sigma ST was identical in patients with large and with small to medium aneurysms. At reinvestigation mean sigma ST was identical in patients with large and with small to medium residual aneurysms as well as in patients with akinesia. Left ventricular end-diastolic pressure before angiography was reduced from a mean value of 21.5 mm to 15.1 mmHg and after angiography from 26.7 mm to 21.1 mmHg. Progression of coronary artery stenoses was a characteristic finding in patients whose left ventricular end-diastolic pressures did not return to normal. These patients had a longer follow-up time than those with no progression of coronary disease, who all showed an improvement in left ventricular end-diastolic pressure. Six patients who had coronary bypass grafting performed had unchanged left ventricular end-diastolic pressures at follow-up. The results indicate that progression of coronary artery disease may be responsible for an eventual further deterioration in left ventricular function after aneurysmectomy. Additional bypass grafting did not result in improved left ventricular function. PMID:6971647

  19. Turning Points: Priorities for Teacher Education in a Democracy

    ERIC Educational Resources Information Center

    Romano, Rosalie M.

    2009-01-01

    Every generation has its moment, some turning point that will mark its place in the historical record. Such points provide the direction of our history and our future. Turning points are, characteristically, times of turmoil based on a fundamental change in models or events--what Thomas Kuhn called a "paradigm shift." In terms of a democratic…

  20. Monitoring of Surface Roughness in Aluminium Turning Process

    NASA Astrophysics Data System (ADS)

    Chaijareenont, Atitaya; Tangjitsitcharoen, Somkiat

    2018-01-01

    As the turning process is one of the most necessary process. The surface roughness has been considered for the quality of workpiece. There are many factors which affect the surface roughness. Hence, the objective of this research is to monitor the relation between the surface roughness and the cutting forces in aluminium turning process with a wide range of cutting conditions. The coated carbide tool and aluminium alloy (Al 6063) are used for this experiment. The cutting parameters are investigated to analyze the effects of them on the surface roughness which are the cutting speed, the feed rate, the tool nose radius and the depth of cut. In the case of this research, the dynamometer is installed in the turret of CNC turning machine to generate a signal while turning. The relation between dynamic cutting forces and the surface roughness profile is examined by applying the Fast Fourier Transform (FFT). The experimentally obtained results showed that the cutting force depends on the cutting condition. The surface roughness can be improved when increasing the cutting speed and the tool nose radius in contrast to the feed rate and the depth of cut. The relation between the cutting parameters and the surface roughness can be explained by the in-process cutting forces. It is understood that the in-process cutting forces are able to predict the surface roughness in the further research.

  1. ClinicalTrials.gov Turns 10! | NIH MedlinePlus the Magazine

    MedlinePlus

    ... please turn Javascript on. Feature: Clinical Trials ClinicalTrials.gov Turns 10! Past Issues / Fall 2010 Table of ... and whom to contact for more information. ClinicalTrials.gov's Helpful Features ClinicalTrials.gov has many helpful consumer ...

  2. Restricted crossing u-turn : informational guide.

    DOT National Transportation Integrated Search

    2014-08-01

    This document provides information and guidance on Restricted Crossing U-Turn (RCUT) intersections. To the extent possible, : the guide addresses a variety of conditions found in the United States, to achieve designs suitable for a wide array of pote...

  3. A Quasar Turns On

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2017-02-01

    The intermediate Palomar Transient Factory (iPTF) has discovered a quasar the brightly-shining, active nucleus of a galaxy abruptly turning on in what appears to be the fastest such transition ever seen in such an object.A Rapid TransitionQuasars are expected to show variations in brightness on timescales of hours to millions of years, but its not often that we get to study their major variability in real time! So far, weve discovered only a dozen changing-look quasars active galactic nuclei that exhibit major changes in their spectral class and brightness between observations. Roughly half of these were quasars that turned on and half were quasars that turned off, generally on timescales of maybe 5 or 10 years.The dramatic change in spectrum of iPTF 16bco between the archival SDSS data from 2004 (bottom) and the follow-up spectroscopy from Keck 2+DEIMOS in 2016 (top). [Adapted from Gezari et al. 2017]In June 2016, however, a team of scientists led by Suvi Gezari (University of Maryland) discovered iPTF 16bco, a nuclear transient that wasnt there the last time Palomar checked in 2012. A search through archival Sloan Digital Sky Survey and GALEX data in addition to some follow-up X-ray imaging and spectroscopic observations told the team what they needed to know: iPTF 16bco is a quasar that only just turned on within the 500 days preceding the iPTF observations.This source, in fact, is a 100-million-solar-mass black hole located at the center of a galaxy at a redshift of z= 0.237. In just over a year, the source changed classification from a galaxy with weak narrow-line emission to a quasar with characteristic strong, broad emission lines and a ten-fold increase in continuum brightness! What caused this sudden transition?Instabilities at Fault?iPTF 16bco and the other known changing-look quasars with disappearing (red circles) and appearing (blue circles) broad-line emission. [Adapted from Gezari et al. 2017]Gezari and collaborators used the large number of recent

  4. A robust automated left ventricle region of interest localization technique using a cardiac cine MRI atlas

    NASA Astrophysics Data System (ADS)

    Ben-Zikri, Yehuda Kfir; Linte, Cristian A.

    2016-03-01

    Region of interest detection is a precursor to many medical image processing and analysis applications, including segmentation, registration and other image manipulation techniques. The optimal region of interest is often selected manually, based on empirical knowledge and features of the image dataset. However, if inconsistently identified, the selected region of interest may greatly affect the subsequent image analysis or interpretation steps, in turn leading to incomplete assessment during computer-aided diagnosis or incomplete visualization or identification of the surgical targets, if employed in the context of pre-procedural planning or image-guided interventions. Therefore, the need for robust, accurate and computationally efficient region of interest localization techniques is prevalent in many modern computer-assisted diagnosis and therapy applications. Here we propose a fully automated, robust, a priori learning-based approach that provides reliable estimates of the left and right ventricle features from cine cardiac MR images. The proposed approach leverages the temporal frame-to-frame motion extracted across a range of short axis left ventricle slice images with small training set generated from les than 10% of the population. This approach is based on histogram of oriented gradients features weighted by local intensities to first identify an initial region of interest depicting the left and right ventricles that exhibits the greatest extent of cardiac motion. This region is correlated with the homologous region that belongs to the training dataset that best matches the test image using feature vector correlation techniques. Lastly, the optimal left ventricle region of interest of the test image is identified based on the correlation of known ground truth segmentations associated with the training dataset deemed closest to the test image. The proposed approach was tested on a population of 100 patient datasets and was validated against the ground truth

  5. Recovery of Neonatal Head Turning to Decreased Sound Pressure Level.

    ERIC Educational Resources Information Center

    Tarquinio, Nancy; And Others

    1990-01-01

    Investigated newborns' responses to decreased sound pressure level (SPL) by means of a localized head turning habituation procedure. Findings, which demonstrated recovery of neonatal head turning to decreased SPL, were inconsistent with the selective receptor adaptation model. (RH)

  6. Methodologies for reducing truck turn time at marine container terminals.

    DOT National Transportation Integrated Search

    2005-05-01

    One of the prominent issues container terminal operators in the US are seeking to address is how to effectively : reduce truck turn time. Historically, truck turn time has received very little attention from terminal operators because port : congesti...

  7. Maneuverability by the sea lion Zalophus californianus: turning performance of an unstable body design.

    PubMed

    Fish, Frank E; Hurley, Jenifer; Costa, Daniel P

    2003-02-01

    Maneuverability is critical to the performance of fast-swimming marine mammals that use rapid turns to catch prey. Overhead video recordings were analyzed for two sea lions (Zalophus californianus) turning in the horizontal plane. Unpowered turns were executed by body flexion in conjunction with use of the pectoral and pelvic flippers, which were used as control surfaces. A 90 degree bank angle was used in the turns to vertically orient the control surfaces. Turning radius was dependent on body mass and swimming velocity. Relative minimum radii were 9-17% of body length and were equivalent for pinnipeds and cetaceans. However, Zalophus had smaller turning radii at higher speeds than cetaceans. Rate of turn was inversely related to turn radius. The highest turn rate observed in Zalophus was 690 degrees s(-1). Centripetal acceleration measured up to 5.1 g for Zalophus. Comparison with other marine mammals indicates that Zalophus has a morphology that enhances instability, thus providing enhanced turning performance. Enhanced turning performance is necessary for sea lions to forage after highly elusive prey in structurally complex environments.

  8. Turn-taking in Human Communication--Origins and Implications for Language Processing.

    PubMed

    Levinson, Stephen C

    2016-01-01

    Most language usage is interactive, involving rapid turn-taking. The turn-taking system has a number of striking properties: turns are short and responses are remarkably rapid, but turns are of varying length and often of very complex construction such that the underlying cognitive processing is highly compressed. Although neglected in cognitive science, the system has deep implications for language processing and acquisition that are only now becoming clear. Appearing earlier in ontogeny than linguistic competence, it is also found across all the major primate clades. This suggests a possible phylogenetic continuity, which may provide key insights into language evolution. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Is there any relationship between right and left hand dominance and right and left nasal airflow dominance?

    PubMed

    Price, A; Eccles, R

    2017-10-01

    Left- or right-handedness is a common human trait, and it has been previously reported that human nasal airflow dominance correlates with hand dominance. Any relationship between hand dominance and nasal airflow dominance would be unusual. This study aimed to measure nasal airflow and look for any relationship to handedness. The modified Glatzel mirror was used to record the dominant nasal passage at 15-minute intervals over a 6-hour period in 29 healthy participants consisting of 15 left-handers and 14 right-handers. In left-handers, the percentage of time that the left nasal passage was dominant ranged from 0 to 100 per cent. In right-handers, the percentage of time that the right nasal passage was dominant ranged from 4.2 to 95.8 per cent. No correlation between nasal airflow dominance and hand dominance was identified. The results do not support the hypothesis that nasal airflow and handedness are related.

  10. Greater Activity in the Frontal Cortex on Left Curves: A Vector-Based fNIRS Study of Left and Right Curve Driving.

    PubMed

    Oka, Noriyuki; Yoshino, Kayoko; Yamamoto, Kouji; Takahashi, Hideki; Li, Shuguang; Sugimachi, Toshiyuki; Nakano, Kimihiko; Suda, Yoshihiro; Kato, Toshinori

    2015-01-01

    In the brain, the mechanisms of attention to the left and the right are known to be different. It is possible that brain activity when driving also differs with different horizontal road alignments (left or right curves), but little is known about this. We found driver brain activity to be different when driving on left and right curves, in an experiment using a large-scale driving simulator and functional near-infrared spectroscopy (fNIRS). The participants were fifteen healthy adults. We created a course simulating an expressway, comprising straight line driving and gentle left and right curves, and monitored the participants under driving conditions, in which they drove at a constant speed of 100 km/h, and under non-driving conditions, in which they simply watched the screen (visual task). Changes in hemoglobin concentrations were monitored at 48 channels including the prefrontal cortex, the premotor cortex, the primary motor cortex and the parietal cortex. From orthogonal vectors of changes in deoxyhemoglobin and changes in oxyhemoglobin, we calculated changes in cerebral oxygen exchange, reflecting neural activity, and statistically compared the resulting values from the right and left curve sections. Under driving conditions, there were no sites where cerebral oxygen exchange increased significantly more during right curves than during left curves (p > 0.05), but cerebral oxygen exchange increased significantly more during left curves (p < 0.05) in the right premotor cortex, the right frontal eye field and the bilateral prefrontal cortex. Under non-driving conditions, increases were significantly greater during left curves (p < 0.05) only in the right frontal eye field. Left curve driving was thus found to require more brain activity at multiple sites, suggesting that left curve driving may require more visual attention than right curve driving. The right frontal eye field was activated under both driving and non-driving conditions.

  11. Investigation of the flow turning loss in unstable solid propellant rocket motors

    NASA Astrophysics Data System (ADS)

    Matta, Lawrence Mark

    The goal of this study was to improve the understanding of the flow turning loss, which contributes to the damping of axial acoustic instabilities in solid propellant rocket motors. This understanding is needed to develop practical methods for designing motors that do not exhibit such instabilities. The flow turning loss results from the interaction of the flow of combustion products leaving the surface of the propellant with the acoustic field in an unstable motor. While state of the art solid rocket stability models generally account for the flow turning loss, its magnitude and characteristics have never been fully investigated. This thesis describes a combined theoretical, numerical, and experimental investigation of the flow turning loss and its dependence upon various motor design and operating parameters. First, a one dimensional acoustic stability equation that verifies the existence of the flow turning loss was derived for a chamber with constant mean pressure and temperature. The theoretical development was then extended to include the effects of mean temperature gradients to accommodate combustion systems in which mean temperature gradients and heat losses are significant. These analyses provided the background and expressions necessary to guide an experimental study. The relevant equations were then solved for the developed experimental setup to predict the behavior of the flow turning loss and the other terms of the developed acoustic stability equation. This was followed by and experimental study in which the flow turning region of an unstable solid propellant rocket motor was simulated. The setup was used, with and without combustion, to determine the dependence of the flow turning loss upon operating conditions. These studies showed that the flow turning loss strongly depends upon the gas velocity at the propellant surface and the location of the flow turning region relative to the standing acoustic wave. The flow turning loss measured in the

  12. Bacteria turn a tiny gear

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

    Aronson, Igor

    2009-01-01

    Thousands of tiny Bacillus subtillis bacteria turn a single gear, just 380 microns across. (A human hair is about 100 microns across.) The method could be used to create micro-machines. Argonne National Laboratory scientist Igor Aronson pioneered this technique. Read more at the New York Times: http://ow.ly/ODfI or at Argonne: http://ow.ly/ODfa Video courtesy Igor Aronson.

  13. [Establishment of visceral left-right asymmetry in mammals: the role of ciliary action and leftward fluid flow in the region of Hensen's node].

    PubMed

    Ermakov, A S

    2013-01-01

    During individual development of vertebrates, the anteroposterior, dorsoventral, and left-right axes of the body are established. Although the vertebrates are bilaterally symmetric outside, their internal structure is asymmetric. Of special interest is the insight into establishment of visceral left-right asymmetry in mammals, since it has not only basic but also an applied medical significance. As early as 1976, it was hypothesized that the ciliary action could be associated with the establishment of left-right asymmetry in mammals. Currently, the majority of researchers agree that the ciliary action in the region of Hensen's node and the resulting leftward laminar fluid flow play a key role in the loss of bilateral symmetry and triggering of expression of the genes constituting the Nodal-Ptx2 signaling cascade, specific of the left side of the embryo. The particular mechanism underlying this phenomenon is still insufficiently clear. There are three competing standpoints on how leftward fluid flow induces expression of several genes in the left side of the embryo. The morphogen gradient hypothesis postulates that the leftward flow creates a high concentration of a signaling biomolecule in the left side of Hensen's node, which, in turn, stimulates triggering of.gene expression of the Nodal-Ptx2 cascade. The biomechanical hypothesis (or two-cilia model) states that the immotile cilia located in the periphery of Hensen's node act as mechanosensors, activate mechanosensory ion channels, and trigger calcium signaling in the left side of the embryo. Finally, the "shuttle-bus model" holds that leftward fluid flow carries the lipid vesicles, which are crashed when colliding immotile cilia in the periphery of Hensen's node to release the contained signaling biomolecules. It is also noteworthy that the association between the ciliary action and establishment of asymmetry has been recently discovered in representatives of the lower invertebrates. In this paper, the author

  14. The left ventricle as a mechanical engine: from Leonardo da Vinci to the echocardiographic assessment of peak power output-to-left ventricular mass.

    PubMed

    Dini, Frank L; Guarini, Giacinta; Ballo, Piercarlo; Carluccio, Erberto; Maiello, Maria; Capozza, Paola; Innelli, Pasquale; Rosa, Gian M; Palmiero, Pasquale; Galderisi, Maurizio; Razzolini, Renato; Nodari, Savina

    2013-03-01

    The interpretation of the heart as a mechanical engine dates back to the teachings of Leonardo da Vinci, who was the first to apply the laws of mechanics to the function of the heart. Similar to any mechanical engine, whose performance is proportional to the power generated with respect to weight, the left ventricle can be viewed as a power generator whose performance can be related to left ventricular mass. Stress echocardiography may provide valuable information on the relationship between cardiac performance and recruited left ventricular mass that may be used in distinguishing between adaptive and maladaptive left ventricular remodeling. Peak power output-to-mass, obtained during exercise or pharmacological stress echocardiography, is a measure that reflects the number of watts that are developed by 100 g of left ventricular mass under maximal stimulation. Power output-to-mass may be calculated as left ventricular power output per 100 g of left ventricular mass: 100× left ventricular power output divided by left ventricular mass (W/100 g). A simplified formula to calculate power output-to-mass is as follows: 0.222 × cardiac output (l/min) × mean blood pressure (mmHg)/left ventricular mass (g). When the integrity of myocardial structure is compromised, a mismatch becomes apparent between maximal cardiac power output and left ventricular mass; when this occurs, a reduction of the peak power output-to-mass index is observed.

  15. Constraining eye movement in individuals with Parkinson's disease during walking turns.

    PubMed

    Ambati, V N Pradeep; Saucedo, Fabricio; Murray, Nicholas G; Powell, Douglas W; Reed-Jones, Rebecca J

    2016-10-01

    Walking and turning is a movement that places individuals with Parkinson's disease (PD) at increased risk for fall-related injury. However, turning is an essential movement in activities of daily living, making up to 45 % of the total steps taken in a given day. Hypotheses regarding how turning is controlled suggest an essential role of anticipatory eye movements to provide feedforward information for body coordination. However, little research has investigated control of turning in individuals with PD with specific consideration for eye movements. The purpose of this study was to examine eye movement behavior and body segment coordination in individuals with PD during walking turns. Three experimental groups, a group of individuals with PD, a group of healthy young adults (YAC), and a group of healthy older adults (OAC), performed walking and turning tasks under two visual conditions: free gaze and fixed gaze. Whole-body motion capture and eye tracking characterized body segment coordination and eye movement behavior during walking trials. Statistical analysis revealed significant main effects of group (PD, YAC, and OAC) and visual condition (free and fixed gaze) on timing of segment rotation and horizontal eye movement. Within group comparisons, revealed timing of eye and head movement was significantly different between the free and fixed gaze conditions for YAC (p < 0.001) and OAC (p < 0.05), but not for the PD group (p > 0.05). In addition, while intersegment timings (reflecting segment coordination) were significantly different for YAC and OAC during free gaze (p < 0.05), they were not significantly different in PD. These results suggest individuals with PD do not make anticipatory eye and head movements ahead of turning and that this may result in altered segment coordination during turning. As such, eye movements may be an important addition to training programs for those with PD, possibly promoting better coordination during turning and

  16. Left-right asymmetry of biophoton emission from hemiparesis patients.

    PubMed

    Jung, Hyun-Hee; Woo, Won-Myung; Yang, Joon-Mo; Choi, Chunho; Lee, Jonghan; Yoon, Gilwon; Yang, Jong S; Lee, Sungmuk; Soh, Kwang-Sup

    2003-05-01

    Left-right biophoton asymmetry from the palm and the dorsum of hands from 7 Korean hemiparesis patients were studied. There is a strong tendency that the left-hemiparesis patients emit more biophotons from the right than the left hands, while the right-hemiparesis patient emits more from the left hand. Acupuncture treatment reduces dramatically the left-right asymmetry of biophoton emission rates. However there is no systematic difference for the patients in the emission rates from the palm and the dorsum of hands.

  17. Crack Turning in Integrally Stiffened Aircraft Structures

    NASA Technical Reports Server (NTRS)

    Pettit, Richard Glen

    2000-01-01

    Current emphasis in the aircraft industry toward reducing manufacturing cost has created a renewed interest in integrally stiffened structures. Crack turning has been identified as an approach to improve the damage tolerance and fail-safety of this class of structures. A desired behavior is for skin cracks to turn before reaching a stiffener, instead of growing straight through. A crack in a pressurized fuselage encounters high T-stress as it nears the stiffener--a condition favorable to crack turning. Also, the tear resistance of aluminum alloys typically varies with crack orientation, a form of anisotropy that can influence the crack path. The present work addresses these issues with a study of crack turning in two-dimensions, including the effects of both T-stress and fracture anisotropy. Both effects are shown to have relation to the process zone size, an interaction that is central to this study. Following an introduction to the problem, the T-stress effect is studied for a slightly curved semi-infinite crack with a cohesive process zone, yielding a closed form expression for the future crack path in an infinite medium. For a given initial crack tip curvature and tensile T-stress, the crack path instability is found to increase with process zone size. Fracture orthotropy is treated using a simple function to interpolate between the two principal fracture resistance values in two-dimensions. An extension to three-dimensions interpolates between the six principal values of fracture resistance. Also discussed is the transition between mode I and mode II fracture in metals. For isotropic materials, there is evidence that the crack seeks out a direction of either local symmetry (pure mode I) or local asymmetry (pure mode II) growth. For orthotropic materials the favored states are not pure modal, and have mode mixity that is a function of crack orientation.

  18. The effect of acute mechanical left ventricular unloading on ovine tricuspid annular size and geometry.

    PubMed

    Malinowski, Marcin; Wilton, Penny; Khaghani, Asghar; Brown, Michael; Langholz, David; Hooker, Victoria; Eberhart, Lenora; Hooker, Robert L; Timek, Tomasz A

    2016-09-01

    Left ventricular assist device (LVAD) implantation may alter right ventricular shape and function and lead to tricuspid regurgitation. This in turn has been reported to be a determinant of right ventricular (RV) failure after LVAD implantation, but the effect of mechanical left ventricular (LV) unloading on the tricuspid annulus is unknown. The aim of the study was to provide insight into the effect of LVAD support on tricuspid annular geometry and dynamics that may help to optimize LV unloading with the least deleterious effect on the right-sided geometry. In seven open-chest anaesthetized sheep, nine sonomicrometry crystals were implanted on the right ventricle. Additional nine crystals were implanted around the tricuspid annulus, with one crystal at each commissure defining three separate annular regions: anterior, posterior and septal. Left ventricular unloading was achieved by connecting a cannula in the left atrium and the aorta to a continuous-flow pump. The pump was used for 15 min at a full flow of 3.8 ± 0.3 l/min. Epicardial echocardiography was used to assess the degree of tricuspid insufficiency. Haemodynamic, echocardiographic and sonomicrometry data were collected before and during full unloading. Tricuspid annular area, and the regional and total perimeter were calculated from crystal coordinates, while 3D annular geometry was expressed as the orthogonal distance of each annular crystal to the least squares plane of all annular crystals. There was no significant tricuspid regurgitation observed either before or during LV unloading. Right ventricular free wall to septum diameter increased significantly at end-diastole during unloading from 23.6 ± 5.8 to 26.3 ± 6.5 mm (P = 0.009), but the right ventricular volume, tricuspid annular area and total perimeter did not change from baseline. However, the septal part of the annulus significantly decreased its maximal length (38.6 ± 8.1 to 37.9 ± 8.2 mm, P = 0.03). Annular contraction was not altered. The

  19. Coronary sinus signal amplitude predicts left atrial scarring.

    PubMed

    Attanasio, Philipp; Qaiyumi, Daniel; Röhle, Robert; Wutzler, Alexander; Safak, Erdal; Muntean, Bogdan; Boldt, Leif-Hendrik; Pieske, Burkert; Haverkamp, Wilhelm; Huemer, Martin

    2017-12-22

    Left atrial scarring is recognised as a critical component in the maintenance of atrial fibrillation and is associated with the failure of interventional treatment. Diminished bipolar voltage (LV) has been proposed as a useful tool for left atrial scar quantification. We hypothesised that, due to its anatomic location, signals on the coronary sinus catheter might be used to predict the amount of left atrial low voltage. A total of 124 patients (42% women, average age 66 ± 9 years) were included. Forty-one with paroxysmal and 83 with persistent atrial fibrillation. Left atrial low-voltage (<0.5 mV, measured during sinus rhythm) area size and distribution varied considerably among the included patients (mean: 34.9%; maximum: 94.6%; minimum: 0.4%). Spearman correlation revealed a strong negative correlation between bipolar voltage of the signals on the coronary sinus catheter and the amount of left atrial scarring (R = -0.778, p < .0001). The optimal CS voltage cut off for prediction of left atrial low-voltage size of ≥50% was 1.9 mV with an area-under-the receiver-operating-characteristic (ROC) curve of 0.982, a sensitivity of 97% and a specificity of 98%. There is a strong negative correlation between the size of left atrial low-voltage areas (LVA) and coronary sinus signal amplitude. With increasing left atrial LVA size, CS signal amplitudes decrease, and vice versa. On the basis of these findings, average CS signal amplitudes of ≤1.9 mV can be used as a predictor for a left atrial low-voltage size of ≥50%.

  20. Pure Left Neglect for Arabic Numerals

    ERIC Educational Resources Information Center

    Priftis, Konstantinos; Albanese, Silvia; Meneghello, Francesca; Pitteri, Marco

    2013-01-01

    Arabic numerals are diffused and language-free representations of number magnitude. To be effectively processed, the digits composing Arabic numerals must be spatially arranged along a left-to-right axis. We studied one patient (AK) to show that left neglect, after right hemisphere damage, can selectively impair the computation of the spatial…

  1. Additional mechanism for left ventricular dysfunction: chronic pulmonary regurgitation decreases left ventricular preload in patients with tetralogy of Fallot.

    PubMed

    Ylitalo, Pekka; Jokinen, Eero; Lauerma, Kirsi; Holmström, Miia; Pitkänen-Argillander, Olli M

    2018-02-01

    Right ventricular dysfunction in patients with tetralogy of Fallot and significant pulmonary regurgitation may lead to systolic dysfunction of the left ventricle due to altered ventricular interaction. We were interested in determining whether chronic pulmonary regurgitation affects the preload of the left ventricle. In addition, we wanted to study whether severe chronic pulmonary regurgitation would alter the preload of the left ventricle when compared with patients having preserved pulmonary valve annulus. The study group comprised 38 patients with tetralogy of Fallot who underwent surgical repair between 1990 and 2003. Transannular patching was required in 21 patients to reconstruct the right ventricular outflow tract. Altogether, 48 age- and gender-matched healthy volunteers were recruited. Cardiac MRI was performed on all study patients to assess the atrial and ventricular volumes and function. Severe pulmonary regurgitation (>30 ml/m2) was present in 13 patients, of whom 11 had a transannular patch, but only two had a preserved pulmonary valve annulus. The ventricular preload volumes from both atria were significantly reduced in patients with severe pulmonary regurgitation, and left ventricular stroke volumes (44.1±4.7 versus 58.9±10.7 ml/m2; p<0.0001) were smaller compared with that in patients with pulmonary regurgitation <30 ml/m2 or in controls. In patients with tetralogy of Fallot, severe pulmonary regurgitation has a significant effect on volume flow through the left atrium. Reduction in left ventricular preload volume may be an additional factor contributing to left ventricular dysfunction.

  2. Role of body surface pressure and kinematics in fish turning

    NASA Astrophysics Data System (ADS)

    Costello, John; Costello, Sean; Dabiri, John; Leftwich, Megan C.

    2017-11-01

    Experiments on freely swimming zebrafish were conducted to study the relative contributions to angular acceleration from both the induced pressure field in the fluid surrounding the animal as well as changes in the body moment of inertia due bending during turning maneuvers. PIV-based pressure measurements indicated that turning is initiated by subtle changes to body posture that create large pressure gradients at the head and tail of the animal. The angular turning motion that results from this pressure-based torque is amplified by the animal bending, which reduces the body moment of inertia during the turn. The demonstrated ability to decouple torque generation and body kinematics, using a combination PIV-based pressure measurements and image-based inertia measurements, can facilitate exploration of maneuvering dynamics in a broader range of swimming species, including a search for possible convergent maneuvering strategies that might be common among aquatic animals.

  3. Turn-over in pulsar spectra: From young pulsars to millisecond ones

    NASA Astrophysics Data System (ADS)

    Kijak, J.; Lewandowski, W.; Serylak, M.

    2008-02-01

    The evidence for turn-over in young pulsar radio spectra at high frequencies is presented. The frequency at which a spectrum shows the maximum flux density is called the peak frequency. This peak frequency appears to depend on pulsar age and dispersion measure. A possible relation with pulsar age is interesting. Millisecond pulsars, which are very old objects, may show no evidence for spectral turn-over down to 100 MHz. Some studied pulsars with turn-over at high frequencies have been shown to have very interesting interstellar environments. This could suggest that the turn-over phenomenon is associated with the enviromental conditions around the neutron stars, rahter than being related intrinsically with the radio emission mechanism. Although there are no earlier reports of such a connection, a more detailed study on larger sample of pulsars is needed to address this idea more quantitatively. In this context, future observations below 200 MHz using LOFAR will allow us to investigate turn-over in radio pulsar spectra.

  4. An investigation into magnetic electrolytic abrasive turning

    NASA Astrophysics Data System (ADS)

    Mahdy, M. A. M.; Ismaeial, A. L.; Aly, F. F.

    2013-07-01

    The magnetic electrolytic abrasive turning (MEAT) process as a non-traditional machining is used to obtain surface finishing like mirror. MEAT provides one of the best alternatives for producing complex shapes with good finish in advanced materials used in aircraft and aerospace industries. The improvement of machining accuracy of MEAT continues to be a major challenge for modern industry. MEAT is a hybrid machining which combines two or more processes to remove material. The present research focuses on the development of precision electrochemical turning (ECT) under the effects of magnetic field and abrasives. The effect of magnetic flux density, electrochemical conditions and abrasive parameters on finishing efficiency and surface roughness are investigated. An empirical relationship is deduced.

  5. Why are some people left-handed? An evolutionary perspective

    PubMed Central

    Llaurens, V.; Raymond, M.; Faurie, C.

    2008-01-01

    Since prehistoric times, left-handed individuals have been ubiquitous in human populations, exhibiting geographical frequency variations. Evolutionary explanations have been proposed for the persistence of the handedness polymorphism. Left-handedness could be favoured by negative frequency-dependent selection. Data have suggested that left-handedness, as the rare hand preference, could represent an important strategic advantage in fighting interactions. However, the fact that left-handedness occurs at a low frequency indicates that some evolutionary costs could be associated with left-handedness. Overall, the evolutionary dynamics of this polymorphism are not fully understood. Here, we review the abundant literature available regarding the possible mechanisms and consequences of left-handedness. We point out that hand preference is heritable, and report how hand preference is influenced by genetic, hormonal, developmental and cultural factors. We review the available information on potential fitness costs and benefits acting as selective forces on the proportion of left-handers. Thus, evolutionary perspectives on the persistence of this polymorphism in humans are gathered for the first time, highlighting the necessity for an assessment of fitness differences between right- and left-handers. PMID:19064347

  6. Incorporating beta-turns and a turn mimetic out of context in loop 1 of the WW domain affords cooperatively folded beta-sheets.

    PubMed

    Kaul, R; Angeles, A R; Jäger, M; Powers, E T; Kelly, J W

    2001-06-06

    To probe the conformational requirements of loop 1 in the Pin1 WW domain, the residues at the i + 2 and i + 3 positions of a beta-turn within this loop were replaced by dPro-Gly and Asn-Gly, which are known to prefer the conformations required at the i + 1 and i + 2 positions of type II' and type I' beta-turns. Conformational specificity or lack thereof was further examined by incorporating into the i + 2 and i + 3 positions a non-alpha-amino acid-based beta-turn mimetic (4-(2'-aminoethyl)-6-dibenzofuran propionic acid residue, 1), which was designed to replace the i + 1 and i + 2 positions of beta-turns. All these Pin WW variants are monomeric and folded as discerned by analytical ultracentrifugation, NMR, and CD. They exhibit cooperative two-state transitions and display thermodynamic stability within 0.5 kcal/mol of the wild-type WW domain, demonstrating that the acquisition of native structure and stability does not require a specific sequence and, by extension, conformation within loop 1. However, it could be that these loop 1 mutations alter the kinetics of antiparallel beta-sheet folding, which will be addressed by subsequent kinetic studies.

  7. Changes and variations in the turning angle of Arctic sea ice

    NASA Astrophysics Data System (ADS)

    Ukita, J.; Honda, M.; Ishizuka, S.

    2012-12-01

    The motion of sea ice is under influences of forcing from winds and currents and of sea ice properties. In facing rapidly changing Arctic climate we are interested in whether we observe and quantify changes in sea ice conditions reflected in its velocity field. Theoretical consideration on the freedrift model predicts a change in the sea ice turning angle with respect to the direction of forcing wind in association with thinning sea ice thickness. Possible changes in atmospheric and ocean boundary layer conditions may be reflected in the sea ice turning angle through modification of both atmospheric and oceanic Ekman spirals. With these in mind this study examines statistical properties of the turning angle of the Arctic sea ice and compares them with atmospheric/ice/ocean conditions for the period of 1979-2010 on the basis of IABP buoy data. Preliminary results indicate that over this period the turning angle has varying trends depending on different seasons. We found weakly significant (>90% level) changes in the turning angle from August to October with the maximum trend in October. The direction of trends is counter-clockwise with respect to the geostrophic wind direction, which is consistent with the thinning of sea ice. The interannual variability of the turning angle for this peak season of the reduced sea ice cover is not the same as that of the Arctic SIE. However, in recent years the turning angle appears to covary with the surface air temperature, providing supporting evidence for the relationship between the angle and sea ice thickness. In the presentation we will provide results on the relationships between the turning angle and atmospheric and oceanic variables and further discuss their implications.

  8. Left Right Patterning, Evolution and Cardiac Development

    PubMed Central

    Dykes, Iain M.

    2018-01-01

    Many aspects of heart development are determined by the left right axis and as a result several congenital diseases have their origins in aberrant left-right patterning. Establishment of this axis occurs early in embryogenesis before formation of the linear heart tube yet impacts upon much later morphogenetic events. In this review I discuss the differing mechanisms by which left-right polarity is achieved in the mouse and chick embryos and comment on the evolution of this system. I then discus three major classes of cardiovascular defect associated with aberrant left-right patterning seen in mouse mutants and human disease. I describe phenotypes associated with the determination of atrial identity and venous connections, looping morphogenesis of the heart tube and finally the asymmetric remodelling of the embryonic branchial arch arterial system to form the leftward looped arch of aorta and associated great arteries. Where appropriate, I consider left right patterning defects from an evolutionary perspective, demonstrating how developmental processes have been modified in species over time and illustrating how comparative embryology can aide in our understanding of congenital heart disease. PMID:29755990

  9. Stuck with/in a 'turn': Can we metaphorize better in Science and Technology Studies?

    PubMed

    Vasileva, Bistra

    2015-06-01

    This contribution encourages loosening the cast-iron mould of the 'turn' metaphor that the practices of general and ontology-related turn-talking/making in Science and Technology Studies forge and fortify. Could framing novel themes and thinking in terms of 'turn' be as good as fettering? Not specific to the 'ontological turn' or 'turn to ontology', but haunting Science and Technology Studies across the board to signify supposed tidal change, the metaphor warrants dissection. Thus, this commentary expounds four distinct yet not unrelated versions of 'turn'--rotation, change of course/direction, change in general and occasion/opportunity to act--together with the worlds they beget. Then, the operation of these 'turns' in the debates on the 'ontological turn' is pursued. Enactments of the first three modes/moulds of 'turn', all entailing and tainted by the inexorable directedness of change the coupled 'turn to' framing imparts, either debunk or qualify the extent of the professed 'turn', with the effect of betraying its conceptual and methodological offerings. The fourth version, less substitutable with 'turn to' and thus less infected by intransigent directedness, escapes the rigidity that diminishes the value of ontology-minded studies. Clear of either a resolution to the debate or an alternative trope to cure the maladies of 'turn', the conclusion wishes to open space for pondering how to metaphorize more consciously and judiciously evolution and innovation in Science and Technology Studies.

  10. A method for simultaneous linear optics and coupling correction for storage rings with turn-by-turn beam position monitor data

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

    Yang, Xi; Huang, Xiaobiao

    2016-08-01

    We propose a method to simultaneously correct linear optics errors and linear coupling for storage rings using turn-by-turn (TbT) beam position monitor (BPM) data. The independent component analysis (ICA) method is used to isolate the betatron normal modes from the measured TbT BPM data. The betatron amplitudes and phase advances of the projections of the normal modes on the horizontal and vertical planes are then extracted, which, combined with dispersion measurement, are used to fit the lattice model. Furthermore, the fitting results are used for lattice correction. Our method has been successfully demonstrated on the NSLS-II storage ring.

  11. A method for simultaneous linear optics and coupling correction for storage rings with turn-by-turn beam position monitor data

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

    Yang, Xi; Huang, Xiaobiao

    2016-08-01

    We propose a method to simultaneously correct linear optics errors and linear coupling for storage rings using turn-by-turn (TbT) beam position monitor (BPM) data. The independent component analysis (ICA) method is used to isolate the betatron normal modes from the measured TbT BPM data. The betatron amplitudes and phase advances of the projections of the normal modes on the horizontal and vertical planes are then extracted, which, combined with dispersion measurement, are used to fit the lattice model. The fitting results are used for lattice correction. The method has been successfully demonstrated on the NSLS-II storage ring.

  12. Turning Vanes inside the Altitude Wind Tunnel

    NASA Image and Video Library

    1944-02-21

    Men stand in front of turning vanes inside the Altitude Wind Tunnel (AWT) at the National Advisory Committee for Aeronautics (NACA) Aircraft Engine Research Laboratory. The AWT was the only wind tunnel capable of testing full-size aircraft engines in simulated altitude conditions. A large wooden drive fan, located on the other side of these vanes, created wind speeds up to 500 miles per hour. The drive shaft connected the fan to the induction motor located in an adjacent building. Turning vanes were located in each corner of the rectangular tunnel to straighten the airflow and direct it around the corners. This set of vanes was located in the 31-foot-diameter southeast corner of the tunnel. These elliptical panels consisted of 36 to 42 vertical vanes that were supported by three horizontal supports. The individual vanes were 2.5 feet long and half-moon shaped. The panel of vanes was affixed to the curved corner rings of the tunnel. Each set of turning vanes had a moveable vane in the middle of the lower level for personnel access. Each set of vanes took weeks to assemble before they were installed during the summer of 1943. This publicity photograph was taken just weeks after the tunnel became operational in February 1944.

  13. Differences in Left and Right Laparoscopic Adrenalectomy

    PubMed Central

    Rieder, Jocelyn M.; Nisbet, Alan A.; Wuerstle, Melanie C.; Tran, Viet Q.; Kwon, Eric O.

    2010-01-01

    Background and Objectives: The classic belief is that right-sided laparoscopic adrenalectomy is technically more difficult to perform than left-sided. The purpose of this study was to determine whether objective outcomes are different for the right- versus left- sided operation. Methods: A retrospective review of 163 laparoscopic adrenalectomies was performed to compare outcomes. Variables extracted included age, demographics, body mass index (BMI), laterality, indication, operative time, estimated blood loss (EBL), gland size, complications, open conversion rates, and length of stay. Results: Of the adrenalectomies performed, 109 were on the left and 54 on the right. Age, BMI, and indication were similar for each group. The mean EBL on the left side was 113mL (range, 2 to 3000) and 84mL (range, 10 to 700) for the right (P=0.85). The mean operative time on the left side was 187 minutes (range, 62 to 475) and on the right was 156 minutes (range, 50 to 365) (P=0.02). There was no difference in complication or conversion rate. Conclusions: There was no difference in complication or conversion rates between each side, and we observed a trend toward lower blood loss for the right side. Although we report generally similar outcomes, the mean operative time for a right-sided laparoscopic adrenalectomy was significantly less (31 minutes) than the left side. PMID:21333190

  14. Egg turning behavior and incubation temperature in Forster's terns in relation to mercury contamination.

    PubMed

    Taylor, Gregory T; Ackerman, Joshua T; Shaffer, Scott A

    2018-01-01

    Egg turning behavior is an important determinant of egg hatchability, but it remains relatively understudied. Here, we examined egg turning rates and egg temperatures in Forster's terns (Sterna forsteri). We used artificial eggs containing a data logger with a 3-D accelerometer, a magnetometer, and a temperature thermistor to monitor parental incubation behavior of 131 tern nests. Overall, adults turned their eggs an average (±SD) of 3.8 ± 0.8 turns h-1, which is nearly two times higher than that of other seabirds. Egg turning rates increased with nest initiation date. We also examined egg turning rates and egg temperatures in relation to egg mercury contamination. Mercury contamination has been shown to be associated with reduced egg hatchability, and we hypothesized that mercury may decrease egg hatchability via altered egg turning behavior by parents. Despite the high variability in egg turning rates among individuals, the rate of egg turning was not related to mercury concentrations in sibling eggs. These findings highlight the need for further study concerning the potential determinants of egg turning behavior.

  15. Time Components of the Left Ventricle.

    ERIC Educational Resources Information Center

    Franks, B. Don

    The purpose of this study was to examine the relationship of the time components of the left ventricle. Since one of the ways to investigate cardiac function is to analyze the time intervals between particular events of the cardiac cycle, various time intervals of systole and diastole of the left ventricle were measured from simultaneous…

  16. Endometriomas are more frequent on the left side.

    PubMed

    Sznurkowski, Jacek J; Emerich, Janosz

    2008-01-01

    To investigate whether asymmetry exists in the left- and right-distribution of ovarian cystic lesions in women with endometriosis. We evaluated operative reports of women who underwent surgical treatment of endometrioma(n = 253) from January 1999 to December 2003. We included only those cases that had not been previously operated on (n = 234). Data of all operative findings consisted of a written report and a diagram, fulfilling the revised American Fertility Society Classification of endometriosis. Endometrioma was found in the left ovary in 113 women, in the right ovaryin 67, and bilaterally in 54. Left ovarian unilateral endometrioma was found more frequently (62.8%) than right endometrioma (p < 0.001, odds ratio (OR) 2.8, 95% confidence interval (CI) 1.9, 4.4). The frequencies of left and right ovarian endometrioma were compared with the expected 50% using Pearson's chi(2)-test. The results confirmed asymmetry(p = 0.001). We found 4 cases of ovarian cancer associated with left endometrioma without histological proof of transition. Our results confirm a left lateral predisposition of endometrioma. This predisposition may be caused by the presence of the sigmoid colon in the left side of the pelvis, which decreases peritoneal fluid movement. Our findings may support the transplantation theory of the origin for endometriosis.

  17. A Right Brain/Left Brain Model of Acting.

    ERIC Educational Resources Information Center

    Bowlen, Clark

    Using current right brain/left brain research, this paper develops a model that explains acting's underlying quality--the actor is both himself and the character. Part 1 presents (1) the background of the right brain/left brain theory, (2) studies showing that propositional communication is a left hemisphere function while affective communication…

  18. Pitch contour matching and interactional alignment across turns: an acoustic investigation.

    PubMed

    Gorisch, Jan; Wells, Bill; Brown, Guy J

    2012-03-01

    In order to explore the influence of context on the phonetic design of talk-in-interaction, we investigated the pitch characteristics of short turns (insertions) that are produced by one speaker between turns from another speaker. We investigated the hypothesis that the speaker of the insertion designs her turn as a pitch match to the prior turn in order to align with the previous speaker's agenda, whereas non-matching displays that the speaker of the insertion is non-aligning, for example to initiate a new action. Data were taken from the AMI meeting corpus, focusing on the spontaneous talk of first-language English participants. Using sequential analysis, 177 insertions were classified as either aligning or non-aligning in accordance with definitions of these terms in the Conversation Analysis literature. The degree of similarity between the pitch contour of the insertion and that of the prior speaker's turn was measured, using a new technique that integrates normalized F0 and intensity information. The results showed that aligning insertions were significantly more similar to the immediately preceding turn, in terms of pitch contour, than were non-aligning insertions. This supports the view that choice of pitch contour is managed locally, rather than by reference to an intonational lexicon.

  19. Turning Parents from Critics to Allies.

    ERIC Educational Resources Information Center

    Sagarese, Margaret M.; Giannetti, Charlene C.

    1998-01-01

    Authors of "The Roller Coaster Years" (1997) advise how middle-level educators can turn wary, disinterested parents into allies. Teachers should welcome parents, advertise their own expertise, implement an early-warning system, portray children positively, convey shared values, reassure parents about children's safety, demonstrate insider…

  20. Effect of transmitter turn-off time on transient soundings

    USGS Publications Warehouse

    Fitterman, D.V.; Anderson, W.L.

    1987-01-01

    A general procedure for computing the effect of non-zero turn-off time on the transient electromagnetic response is presented which can be applied to forward and inverse calculation methods for any transmitter-receiver configuration. We consider in detail the case of a large transmitter loop which has a receiver coil located at the center of the loop (central induction or in-loop array). For a linear turn-off ramp of width t0, the voltage response is shown to be the voltage due to an ideal step turn-off averaged over windows of width t0. Thus the effect is similar to that obtained by using averaging windows in the receiver. In general when time zero is taken to be the end of the ramp, the apparent resistivity increases for a homogeneous half-space over a limited time range. For time zero taken to be the start of the ramp the apparent resistivity is affected in the opposite direction. The effect of the ramp increases with increasing t0 and first-layer resistivity, is largest during the intermediate stage, and decreases with increasing time. It is shown that for a ramp turn-off, there is no effect in the early and late stages. For two-layered models with a resistive first layer (??1>??2), the apparent resistivity is increased in the intermediate stage. When the first layer is more conductive than the second layer (??1turn-off effect. Neglecting the turn-off ramp will affect data interpretation as shown by field examples; the influence is the greatest on near-surface layer parameters. ?? 1987.

  1. Singular perturbations and vanishing passage through a turning point

    NASA Astrophysics Data System (ADS)

    De Maesschalck, P.; Dumortier, F.

    The paper deals with planar slow-fast cycles containing a unique generic turning point. We address the question on how to study canard cycles when the slow dynamics can be singular at the turning point. We more precisely accept a generic saddle-node bifurcation to pass through the turning point. It reveals that in this case the slow divergence integral is no longer the good tool to use, but its derivative with respect to the layer variable still is. We provide general results as well as a number of applications. We show how to treat the open problems presented in Artés et al. (2009) [1] and Dumortier and Rousseau (2009) [13], dealing respectively with the graphics DI2a and DF1a from Dumortier et al. (1994) [14].

  2. Greater Activity in the Frontal Cortex on Left Curves: A Vector-Based fNIRS Study of Left and Right Curve Driving

    PubMed Central

    Oka, Noriyuki; Yoshino, Kayoko; Yamamoto, Kouji; Takahashi, Hideki; Li, Shuguang; Sugimachi, Toshiyuki; Nakano, Kimihiko; Suda, Yoshihiro; Kato, Toshinori

    2015-01-01

    Objectives In the brain, the mechanisms of attention to the left and the right are known to be different. It is possible that brain activity when driving also differs with different horizontal road alignments (left or right curves), but little is known about this. We found driver brain activity to be different when driving on left and right curves, in an experiment using a large-scale driving simulator and functional near-infrared spectroscopy (fNIRS). Research Design and Methods The participants were fifteen healthy adults. We created a course simulating an expressway, comprising straight line driving and gentle left and right curves, and monitored the participants under driving conditions, in which they drove at a constant speed of 100 km/h, and under non-driving conditions, in which they simply watched the screen (visual task). Changes in hemoglobin concentrations were monitored at 48 channels including the prefrontal cortex, the premotor cortex, the primary motor cortex and the parietal cortex. From orthogonal vectors of changes in deoxyhemoglobin and changes in oxyhemoglobin, we calculated changes in cerebral oxygen exchange, reflecting neural activity, and statistically compared the resulting values from the right and left curve sections. Results Under driving conditions, there were no sites where cerebral oxygen exchange increased significantly more during right curves than during left curves (p > 0.05), but cerebral oxygen exchange increased significantly more during left curves (p < 0.05) in the right premotor cortex, the right frontal eye field and the bilateral prefrontal cortex. Under non-driving conditions, increases were significantly greater during left curves (p < 0.05) only in the right frontal eye field. Conclusions Left curve driving was thus found to require more brain activity at multiple sites, suggesting that left curve driving may require more visual attention than right curve driving. The right frontal eye field was activated under both

  3. Super Secondary Structure Consisting of a Polyproline II Helix and a β-Turn in Leucine Rich Repeats in Bacterial Type III Secretion System Effectors.

    PubMed

    Batkhishig, Dashdavaa; Bilguun, Khurelbaatar; Enkhbayar, Purevjav; Miyashita, Hiroki; Kretsinger, Robert H; Matsushima, Norio

    2018-06-01

    Leucine rich repeats (LRRs) are present in over 100,000 proteins from viruses to eukaryotes. The LRRs are 20-30 residues long and occur in tandem. LRRs form parallel stacks of short β-strands and then assume a super helical arrangement called a solenoid structure. Individual LRRs are separated into highly conserved segment (HCS) with the consensus of LxxLxLxxNxL and variable segment (VS). Eight classes have been recognized. Bacterial LRRs are short and characterized by two prolines in the VS; the consensus is xxLPxLPxx with Nine residues (N-subtype) and xxLPxxLPxx with Ten residues (T-subtype). Bacterial LRRs are contained in type III secretion system effectors such as YopM, IpaH3/9.8, SspH1/2, and SlrP from bacteria. Some LRRs in decorin, fribromodulin, TLR8/9, and FLRT2/3 from vertebrate also contain the motifs. In order to understand structural features of bacterial LRRs, we performed both secondary structures assignments using four programs-DSSP-PPII, PROSS, SEGNO, and XTLSSTR-and HELFIT analyses (calculating helix axis, pitch, radius, residues per turn, and handedness), based on the atomic coordinates of their crystal structures. The N-subtype VS adopts a left handed polyproline II helix (PPII) with four, five or six residues and a type I β-turn at the C-terminal side. Thus, the N-subtype is characterized by a super secondary structure consisting of a PPII and a β-turn. In contrast, the T-subtype VS prefers two separate PPIIs with two or three and two residues. The HELFIT analysis indicates that the type I β-turn is a right handed helix. The HELFIT analysis determines three unit vectors of the helix axes of PPII (P), β-turn (B), and LRR domain (A). Three structural parameters using these three helix axes are suggested to characterize the super secondary structure and the LRR domain.

  4. Worsening of left ventricular end-systolic volume and mitral regurgitation without increase in left ventricular dyssynchrony on acute interruption of cardiac resynchronization therapy.

    PubMed

    Kuppahally, Suman S; Fowler, Michael B; Vagelos, Randall; Wang, Paul; Al-Ahmad, Amin; Paloma, Allan; Liang, David

    2009-08-01

    Responders to cardiac resynchronization therapy (CRT) have greater left ventricular (LV) dyssynchrony than nonresponders prior to CRT. We conducted this study to see whether the long term responders have more worsening of LV dyssynchrony and LV function on acute interruption of CRT. We identified 22 responders and 13 nonresponders who received CRT as per standard criteria for 23.73 +/- 7.9 months (median 24.5 months). We assessed the acute change in LV function, mitral regurgitation (MR) and compared LV dyssynchrony in CRT on and off modes. On turning off CRT, there was no significant worsening of LV dyssynchrony in both responders and nonresponders. The dyssynchrony measurements by SPWMD, TDI and 3D echocardiography did not correlate significantly. LVESV increased (p = 0.02) and MR (p = 0.01) worsened in CRT-off mode in responders only without significant change in LVEF or LV dimensions. In long-term responders to CRT, there is alteration in the function of remodeled LV with acute interruption of CRT, without significant worsening of LV dyssynchrony. The role of different echocardiographic parameters in the assessment of LV dyssynchrony remains controversial. Even after long-term CRT reversely remodels the LV, the therapy needs to be continued uninterrupted for sustained benefits.

  5. The Effect on the Sperry Directional Gyro in Turning

    NASA Technical Reports Server (NTRS)

    RosselliDelTurco, Rossello

    1946-01-01

    The present report is concerned with an analytical treatment of the effects of the transverse inclination of an airplane in a turn on the indication of the directional gyro. It is found that the extreme inclinations which the airplane must necessarily assume for a correct turn in the approaches executed at high speed and small radius of curvature, renders the indications of the instrument worthless during such maneuvers.

  6. Extreme premature with persistent left superior vena cava.

    PubMed

    Aboitiz-Rivera, Carlos Manuel; Blachman-Braun, Ruben; Parra-Pérez, Mariana Yazmin

    2017-10-01

    Persistent left superior vena cava (PLSVC) is a congenital anomaly, that results when there is an absence of the normal regression of the left common precardinal vein during embryogenesis. Usually, this anomaly remains asymptomatic, however, when the PLSVC drains into the left atrium this could lead to a right-to-left shunt. Additionally, this can result in inadvertent delivery of air or thrombus into the systemic circulation with potential neurologic, cardiac and renal complications. In this article, we present a case of an extreme premature Mexican newborn in which the diagnosis was made after placement of a percutaneous central venues catheter.

  7. Roles of beta-turns in protein folding: from peptide models to protein engineering.

    PubMed

    Marcelino, Anna Marie C; Gierasch, Lila M

    2008-05-01

    Reverse turns are a major class of protein secondary structure; they represent sites of chain reversal and thus sites where the globular character of a protein is created. It has been speculated for many years that turns may nucleate the formation of structure in protein folding, as their propensity to occur will favor the approximation of their flanking regions and their general tendency to be hydrophilic will favor their disposition at the solvent-accessible surface. Reverse turns are local features, and it is therefore not surprising that their structural properties have been extensively studied using peptide models. In this article, we review research on peptide models of turns to test the hypothesis that the propensities of turns to form in short peptides will relate to the roles of corresponding sequences in protein folding. Turns with significant stability as isolated entities should actively promote the folding of a protein, and by contrast, turn sequences that merely allow the chain to adopt conformations required for chain reversal are predicted to be passive in the folding mechanism. We discuss results of protein engineering studies of the roles of turn residues in folding mechanisms. Factors that correlate with the importance of turns in folding indeed include their intrinsic stability, as well as their topological context and their participation in hydrophobic networks within the protein's structure.

  8. Roles of β-Turns in Protein Folding: From Peptide Models to Protein Engineering

    PubMed Central

    Marcelino, Anna Marie C.; Gierasch, Lila M.

    2010-01-01

    Reverse turns are a major class of protein secondary structure; they represent sites of chain reversal and thus sites where the globular character of a protein is created. It has been speculated for many years that turns may nucleate the formation of structure in protein folding, as their propensity to occur will favor the approximation of their flanking regions and their general tendency to be hydrophilic will favor their disposition at the solvent-accessible surface. Reverse turns are local features, and it is therefore not surprising that their structural properties have been extensively studied using peptide models. In this article, we review research on peptide models of turns to test the hypothesis that the propensities of turns to form in short peptides will relate to the roles of corresponding sequences in protein folding. Turns with significant stability as isolated entities should actively promote the folding of a protein, and by contrast, turn sequences that merely allow the chain to adopt conformations required for chain reversal are predicted to be passive in the folding mechanism. We discuss results of protein engineering studies of the roles of turn residues in folding mechanisms. Factors that correlate with the importance of turns in folding indeed include their intrinsic stability, as well as their topological context and their participation in hydrophobic networks within the protein’s structure. PMID:18275088

  9. Building a stable RNA U-turn with a protonated cytidine.

    PubMed

    Gottstein-Schmidtke, Sina R; Duchardt-Ferner, Elke; Groher, Florian; Weigand, Julia E; Gottstein, Daniel; Suess, Beatrix; Wöhnert, Jens

    2014-08-01

    The U-turn is a classical three-dimensional RNA folding motif first identified in the anticodon and T-loops of tRNAs. It also occurs frequently as a building block in other functional RNA structures in many different sequence and structural contexts. U-turns induce sharp changes in the direction of the RNA backbone and often conform to the 3-nt consensus sequence 5'-UNR-3' (N = any nucleotide, R = purine). The canonical U-turn motif is stabilized by a hydrogen bond between the N3 imino group of the U residue and the 3' phosphate group of the R residue as well as a hydrogen bond between the 2'-hydroxyl group of the uridine and the N7 nitrogen of the R residue. Here, we demonstrate that a protonated cytidine can functionally and structurally replace the uridine at the first position of the canonical U-turn motif in the apical loop of the neomycin riboswitch. Using NMR spectroscopy, we directly show that the N3 imino group of the protonated cytidine forms a hydrogen bond with the backbone phosphate 3' from the third nucleotide of the U-turn analogously to the imino group of the uridine in the canonical motif. In addition, we compare the stability of the hydrogen bonds in the mutant U-turn motif to the wild type and describe the NMR signature of the C+-phosphate interaction. Our results have implications for the prediction of RNA structural motifs and suggest simple approaches for the experimental identification of hydrogen bonds between protonated C-imino groups and the phosphate backbone. © 2014 Gottstein-Schmidtke et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.

  10. Building a stable RNA U-turn with a protonated cytidine

    PubMed Central

    Gottstein-Schmidtke, Sina R.; Duchardt-Ferner, Elke; Groher, Florian; Weigand, Julia E.; Gottstein, Daniel; Suess, Beatrix; Wöhnert, Jens

    2014-01-01

    The U-turn is a classical three-dimensional RNA folding motif first identified in the anticodon and T-loops of tRNAs. It also occurs frequently as a building block in other functional RNA structures in many different sequence and structural contexts. U-turns induce sharp changes in the direction of the RNA backbone and often conform to the 3-nt consensus sequence 5′-UNR-3′ (N = any nucleotide, R = purine). The canonical U-turn motif is stabilized by a hydrogen bond between the N3 imino group of the U residue and the 3′ phosphate group of the R residue as well as a hydrogen bond between the 2′-hydroxyl group of the uridine and the N7 nitrogen of the R residue. Here, we demonstrate that a protonated cytidine can functionally and structurally replace the uridine at the first position of the canonical U-turn motif in the apical loop of the neomycin riboswitch. Using NMR spectroscopy, we directly show that the N3 imino group of the protonated cytidine forms a hydrogen bond with the backbone phosphate 3′ from the third nucleotide of the U-turn analogously to the imino group of the uridine in the canonical motif. In addition, we compare the stability of the hydrogen bonds in the mutant U-turn motif to the wild type and describe the NMR signature of the C+-phosphate interaction. Our results have implications for the prediction of RNA structural motifs and suggest simple approaches for the experimental identification of hydrogen bonds between protonated C-imino groups and the phosphate backbone. PMID:24951555

  11. Annular subvalvular left ventricular aneurysm in Bahia, Brazil.

    PubMed Central

    Guimarães, A C; Filho, A S; Esteves, J P; Abreu, W N; Vinhaes, L A; de Almeida Souza, J A; Machado, A

    1976-01-01

    Two cases of left ventricular aneurysm, a 16-year-old black boy and a 23-year-old white girl, from Bahia, Brazil, are presented. In both patients there was enlargement of the cardiac silhouette and a prominent bulge of the left inferior border. On the right oblique view a ring of calcium at the ventricular opening of the aneurysms was visualized. A left ventriculogram showed a huge aneurysm in the first case and a bulge on the lateral wall of the left ventricle in the other. Cardiac catheterization showed a rise in left and right ventricular end-diastolic pressures and in the mean pulmonary artery pressure. In the first case the contour of the right ventricular pressure curve showed a restrictive pattern. The similarities of these aneurysms with the annular submitral type described in young black Africans are stressed. Images PMID:973882

  12. Annular subvalvular left ventricular aneurysm in Bahia, Brazil.

    PubMed

    Guimarães, A C; Filho, A S; Esteves, J P; Abreu, W N; Vinhaes, L A; de Almeida Souza, J A; Machado, A

    1976-10-01

    Two cases of left ventricular aneurysm, a 16-year-old black boy and a 23-year-old white girl, from Bahia, Brazil, are presented. In both patients there was enlargement of the cardiac silhouette and a prominent bulge of the left inferior border. On the right oblique view a ring of calcium at the ventricular opening of the aneurysms was visualized. A left ventriculogram showed a huge aneurysm in the first case and a bulge on the lateral wall of the left ventricle in the other. Cardiac catheterization showed a rise in left and right ventricular end-diastolic pressures and in the mean pulmonary artery pressure. In the first case the contour of the right ventricular pressure curve showed a restrictive pattern. The similarities of these aneurysms with the annular submitral type described in young black Africans are stressed.

  13. Modulation of left primary motor cortex excitability after bimanual training and intermittent theta burst stimulation to left dorsal premotor cortex.

    PubMed

    Neva, Jason L; Vesia, Michael; Singh, Amaya M; Staines, W Richard

    2014-03-15

    Bimanual visuomotor movement training (BMT) enhances the excitability of human preparatory premotor and primary motor (M1) cortices compared to unimanual movement. This occurs when BMT involves mirror symmetrical movements of both upper-limbs (in-phase) but not with non-symmetrical movements (anti-phase). The neural mechanisms mediating the effect of BMT is unclear, but may involve interhemispheric connections between homologous M1 representations as well as the dorsal premotor cortices (PMd). The purpose of this study is to assess how intermittent theta burst stimulation (iTBS) of the left PMd affects left M1 excitability, and the possible combined effects of iTBS to left PMd applied before a single session of BMT. Left M1 excitability was quantified using transcranial magnetic stimulation (TMS) in terms of both the amplitudes and spatial extent of motor evoked potentials (MEPs) for the extensor carpi radialis (ECR) before and multiple time points following (1) BMT, (2) iTBS to left PMd or (3) iTBS to left PMd and BMT. Although there was not a greater increase in either specific measure of M1 excitability due to the combination of the interventions, iTBS applied before BMT showed that both the spatial extent and global MEP amplitude for the ECR became larger in parallel, whereas the spatial extent was enhanced with BMT alone and global MEP amplitude was enhanced with iTBS to left PMd alone. These results suggest that the modulation of rapid functional M1 excitability associated with BMT and iTBS of the left PMd could operate under related early markers of neuro-plastic mechanisms, which may be expressed in concurrent and distinct patterns of M1 excitability. Critically, this work may guide rehabilitation training and stimulation techniques that modulate cortical excitability after brain injury. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Kinematical Comparison of the 200 m Backstroke Turns between National and Regional Level Swimmers

    PubMed Central

    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

  15. Anatomical study of the left superior mediastinal lymphatics for tracheal branches of left recurrent laryngeal nerve-preserving mediastinoscope-assisted surgery in esophageal cancer.

    PubMed

    Nakajima, Yutaka; Tokairin, Yutaka; Nakajima, Yasuaki; Kawada, Kenro; Nagai, Kagami; Yamaguchi, Kumiko; Akita, Keiichi; Kawano, Tatsuyuki

    2018-03-01

    Curative treatment of esophageal cancer requires meticulous superior mediastinal lymphadenectomy, in addition to esophagectomy, because superior mediastinal lymph node metastases are common in esophageal cancer. When preserving the tracheal branches of the left recurrent laryngeal nerve (RLN), good anatomical understanding is required for confirmation of the positional relationships between the courses of lymphatic vessels, lymph node distribution, and the left RLN and its tracheal branches. We performed a detailed anatomical examination of these relationships. Macroscopic anatomical observation and histological examination was performed on cadavers. In addition to hematoxylin and eosin staining, immunostaining using antipodoplanin antibody D2-40 (podoplanin) was performed to identify the lymphatic vessels. The tracheal branches of the left RLN were clearly observed, but no lymphatic vessels crossing the ventral or dorsal side of the branches were identified either macro-anatomically or histologically. No complex lymphatic network structure straddling the plane composed of tracheal branches of the left RLN was found in the left superior mediastinum. This suggests that dissection of the lymph nodes around the left RLN via the pneumomediastinum method using the left cervical approach may allow preservation of the tracheal branches of the left RLN by maintaining dissection accuracy.

  16. A Practice Turn for Teacher Education?

    ERIC Educational Resources Information Center

    Reid, Jo-Anne

    2011-01-01

    Within the Research Institute for Professional Practice, Learning and Education (RIPPLE) at Charles Sturt University, teacher education researchers have been quick to respond to the opportunities created by what is known as "the practice turn" that characterises contemporary theory around the globe and across disciplines. We are working,…

  17. Business Intelligence: Turning Knowledge into Power

    ERIC Educational Resources Information Center

    Endsley, Krista

    2009-01-01

    Today, many school districts are turning to business intelligence tools to retrieve, organize, and share knowledge for faster analysis and more effective, guided decision making. Business intelligence (BI) tools are the technologies and applications that gather and report information to help an organization's leaders make better decisions. BI…

  18. Novel β-amyloid aggregation inhibitors possessing a turn mimic.

    PubMed

    Hamada, Yoshio; Miyamoto, Naoko; Kiso, Yoshiaki

    2015-04-01

    Amyloid β peptide, the main component of senile plaques found in the brain of Alzheimer disease (AD) patients, is a molecular target for AD therapeutic intervention. A number of potential AD therapeutics have been reported, including inhibitors of β-secretase, γ-secretase, and Aβ aggregation, and anti-amyloid agents, such as neprilysin, insulin degrading enzyme (IDE), and Aβ antibodies. Recently, we reported potent small-sized β-secretase (BACE1) inhibitors, which could serve as anti-AD drugs. However AD is a progressive disorder, where dementia symptoms gradually worsen over several decades, and therefore may require many years to get cured. One possible way to achieve a greater therapeutic effect is through simultaneous administration of multiple drugs, similar to those used in Highly Active Anti-Retroviral Therapy (HAART) used to treat AIDS. In order to overcome AD, we took a drug discovery approach to evaluate, novel β-amyloid aggregation inhibitors. Previously, we reported that a tong-type compound possessing a turn mimic as the inhibitor of HIV-1 protease dimerization. Oligomerized amyloid β peptides contain a turn structure within the molecule. Here, we designed and synthesized novel β-amyloid aggregation inhibitors with a turn-mimic template, based on the turn conformer of the oligomerized amyloid β peptides. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. A method for simultaneous linear optics and coupling correction for storage rings with turn-by-turn beam position monitor data

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

    Yang, Xi; Huang, Xiaobiao

    2016-05-13

    Here, we propose a method to simultaneously correct linear optics errors and linear coupling for storage rings using turn-by-turn (TbT) beam position monitor (BPM) data. The independent component analysis (ICA) method is used to isolate the betatron normal modes from the measured TbT BPM data. The betatron amplitudes and phase advances of the projections of the normal modes on the horizontal and vertical planes are then extracted, which, combined with dispersion measurement, are used to fit the lattice model. The fitting results are used for lattice correction. Finally, the method has been successfully demonstrated on the NSLS-II storage ring.

  20. Efficiency of static core turn-off in a system-on-a-chip with variation

    DOEpatents

    Cher, Chen-Yong; Coteus, Paul W; Gara, Alan; Kursun, Eren; Paulsen, David P; Schuelke, Brian A; Sheets, II, John E; Tian, Shurong

    2013-10-29

    A processor-implemented method for improving efficiency of a static core turn-off in a multi-core processor with variation, the method comprising: conducting via a simulation a turn-off analysis of the multi-core processor at the multi-core processor's design stage, wherein the turn-off analysis of the multi-core processor at the multi-core processor's design stage includes a first output corresponding to a first multi-core processor core to turn off; conducting a turn-off analysis of the multi-core processor at the multi-core processor's testing stage, wherein the turn-off analysis of the multi-core processor at the multi-core processor's testing stage includes a second output corresponding to a second multi-core processor core to turn off; comparing the first output and the second output to determine if the first output is referring to the same core to turn off as the second output; outputting a third output corresponding to the first multi-core processor core if the first output and the second output are both referring to the same core to turn off.

  1. Giant Left Atrium with Rheumatic Mitral Stenosis

    PubMed Central

    Ates, Mehmet; Sensoz, Yavuz; Abay, Gunseli; Akcar, Murat

    2006-01-01

    A chest radiograph of a 38-year-old woman, who was diagnosed with rheumatic mitral stenosis, revealed cardiac enlargement due to a giant left atrium that was distorting the cardiac structures. The patient's cardiothoracic ratio was approximately 0.90. A giant left atrium can readily be delineated by echocardiography. Optimal timing of surgery is important in cases of mitral stenosis, because delaying mitral valve replacement can lead to fatal outcomes. To our knowledge, the left atrial diameter of 18.7 cm that we found in our patient is the largest reported to date. PMID:17041705

  2. Lower extremity control during turns initiated with and without hip external rotation.

    PubMed

    Zaferiou, Antonia M; Flashner, Henryk; Wilcox, Rand R; McNitt-Gray, Jill L

    2017-02-08

    The pirouette turn is often initiated in neutral and externally rotated hip positions by dancers. This provides an opportunity to investigate how dancers satisfy the same mechanical objectives at the whole-body level when using different leg kinematics. The purpose of this study was to compare lower extremity control strategies during the turn initiation phase of pirouettes performed with and without hip external rotation. Skilled dancers (n=5) performed pirouette turns with and without hip external rotation. Joint kinetics during turn initiation were determined for both legs using ground reaction forces (GRFs) and segment kinematics. Hip muscle activations were monitored using electromyography. Using probability-based statistical methods, variables were compared across turn conditions as a group and within-dancer. Despite differences in GRFs and impulse generation between turn conditions, at least 90% of each GRF was aligned with the respective leg plane. A majority of the net joint moments at the ankle, knee, and hip acted about an axis perpendicular to the leg plane. However, differences in shank alignment relative to the leg plane affected the distribution of the knee net joint moment when represented with respect to the shank versus the thigh. During the initiation of both turns, most participants used ankle plantar flexor moments, knee extensor moments, flexor and abductor moments at the push leg׳s hip, and extensor and abductor moments at the turn leg׳s hip. Representation of joint kinetics using multiple reference systems assisted in understanding control priorities. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Why Critical Literacy Should Turn to "The Affective Turn": Making a Case for Critical Affective Literacy

    ERIC Educational Resources Information Center

    Anwaruddin, Sardar M.

    2016-01-01

    The central argument of this essay is that critical literacy with a rationalistic bent may not enable us to cope with ethical dilemmas in our responsiveness to human sufferings. I argue that critical literacy education would benefit from turning to the recent scholarship on affect/emotion studies. I draw upon the works of Sara Ahmed--one of the…

  4. High explosive corner turning performance and the LANL Mushroom test

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

    Hill, L.G.; Seitz, W.L.; Forest, C.A.

    1997-09-01

    The Mushroom test is designed to characterize the corner turning performance of a new generation of less insensitive booster explosives. The test is described in detail, and three corner turning figures-of-merit are examined using pure TATB (both Livermore`s Ultrafine and a Los Alamos research blend) and PBX9504 as examples.

  5. Left ventricular pseudoaneurysm - a challenging diagnosis.

    PubMed

    Faustino, Mariana; Ranchordás, Sara; Abecasis, João; Freitas, António; Ferreira, Moradas; Gil, Victor; Morais, Carlos; Neves, José Pedro

    2016-06-01

    Left ventricular pseudoaneurysm is a rare complication of acute myocardial infarction, associated with high mortality. However, it can present in a non-specific manner, complicating and delaying the diagnosis. The authors present the case of a 65-year-old patient, hypertensive, with no other known relevant medical history, who presented with chest pain, cough and left pleural effusion, initially attributed to a pulmonary process. However, these were in fact the result of a left ventricular pseudoaneurysm following silent acute myocardial infarction. The diagnosis was suspected on echocardiography and confirmed by cardiac magnetic resonance imaging, and the patient underwent successful surgical pseudoaneurysm repair. This case illustrates an atypical presentation of a left ventricular pseudoaneurysm, in which the manifestations resulted from pericardial and pleural extension of the inflammatory process associated with contained myocardial rupture. The case demonstrates the need for a high index of suspicion, and the value of imaging techniques to confirm it, in order to proceed with appropriate surgical treatment, and thus modify the course of the disease. Copyright © 2015 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

  6. Persistent left unilateral mirror writing: A neuropsychological case study.

    PubMed

    Angelillo, Valentina G; De Lucia, Natascia; Trojano, Luigi; Grossi, Dario

    2010-09-01

    Mirror writing (MW) is a rare disorder in which a script runs in direction opposite to normal and individual letters are reversed. The disorder generally occurs after left-hemisphere lesions, is transient and is observed on the left hand, whereas usually motor impairments prevent assessment of direction of right handwriting. We describe a left-handed patient with complete left hand mirror writing, still evident 2 years after a hemorrhagic stroke in left nucleo-capsular region. Since the patient could write with his right hand he underwent several writing tasks with either hand, and a thorough assessment to clarify the nature of MW. MW was evident in writing to dictation with left hand only, both in right and left hemispace, but the patient could modify his behavior when a verbal instruction was provided. No mirror errors were found in reading words, in copying geometric figures and in spatial orientation tasks. MW in our patient could be accounted for by a failure in automatic transformation of grapho-motor programs to write with the left hand. A lack of concern (a sort of anosodiaphoria) and a poor cognitive flexibility could contribute to long-term persistence of MW. 2010 Elsevier Inc. All rights reserved.

  7. Radionuclide evaluation of left ventricular function with nonimaging probes.

    PubMed

    Wexler, J P; Blaufox, M D

    1979-10-01

    Portable nonimaging probes have been developed that can evaluate left ventricular function using radionuclide techniques. Two modes of data acquisition are possible with these probe systems, first-pass and gated. Precordial radiocardiograms obtained after a bolus injection can be used to determine cardiac output, pulmonary transit time, pulmonary blood volume, left ventricle ejection fraction, and left-to-right shunts. Gated techniques can be used to determine left ventricular ejection fraction and sytolic time intervals. Probe-determined indices of left ventricular function agree excellently with comparable measurements determined by conventional camera-computer methods as well as by invasive techniques. These have begun to be used in a preliminary manner in a variety of clinical problems associated with left ventricular dysfunction. This review discusses the types of probe systems available, the methods used in positioning them, and details the specifics of their data acquisition and processing capacity. The major criticisms of probe methods are that they are nonimaging and that they measure global rather than regional left ventricular function. In spite of these criticisms, probe systems, because of their portability, high sensitivity, and relatively low cost are useful supplements to conventional camera-computer systems for the measurement of parameters of left ventricular performance using radionuclide techniques.

  8. Anatomical considerations for the management of a left-sided superior caval vein draining to the roof of the left atrium.

    PubMed

    Saundankar, Jelena; Ho, Andrew B; Salmon, Anthony P; Anderson, Robert H; Magee, Alan G

    2017-07-01

    Aims The pathophysiological entity of a persisting left-sided superior caval vein draining into the roof of the left atrium represents an extreme form of coronary sinus de-roofing. This is an uncommon, but well-documented condition associated with systemic desaturation due to a right-to-left shunt. Depending on the size of the coronary ostium, the defect may also present with right-sided volume loading. We describe two patients, both of whom presented with desaturation, and highlight the important anatomical features underscoring management. Methods and Results Both patients were managed interventionally with previous assessment of the size of the coronary sinus ostium through cross-sectional imaging. This revealed a restrictive interatrial communication at the right atrial mouth of the coronary sinus in both patients, which permitted an interventional approach, as the residual left-to-right shunt subsequent to closure of the aberrant vessel would be negligible. At intervention, test occlusion of the left superior caval vein allowed assessment of decompressing vessels before successful occlusion using an Amplatzer Vascular Plug. Persistence of a left superior caval vein draining to the left atrium may be associated with an interatrial communication at the mouth of the unroofed coronary sinus. The ostium of the de-roofed coronary sinus can be atretic, restrictive, normally sized, or enlarged. Careful assessment of the size of this defect is required before treatment. In view of its importance, which has received little attention in the literature to date, we suggest an additional consideration to the classification of unroofed coronary sinus.

  9. The right way to kiss: directionality bias in head-turning during kissing.

    PubMed

    Karim, A K M Rezaul; Proulx, Michael J; de Sousa, Alexandra A; Karmaker, Chhanda; Rahman, Arifa; Karim, Fahria; Nigar, Naima

    2017-07-14

    Humans have a bias for turning to the right in a number of settings. Here we document a bias in head-turning to the right in adult humans, as tested in the act of kissing. We investigated head-turning bias in both kiss initiators and kiss recipients for lip kissing, and took into consideration differences due to sex and handedness, in 48 Bangladeshi heterosexual married couples. We report a significant male bias in the initiation of kissing and a significant bias in head-turning to the right in both kiss initiators and kiss recipients, with a tendency among kiss recipients to match their partners' head-turning direction. These interesting outcomes are explained by the influences of societal learning or cultural norms and the potential neurophysiological underpinnings which together offer novel insights about the mechanisms underlying behavioral laterality in humans.

  10. Do we overestimate left ventricular ejection fraction by two-dimensional echocardiography in patients with left bundle branch block?

    PubMed

    Cabuk, Ali K; Cabuk, Gizem; Sayin, Ahmet; Karamanlioglu, Murat; Kilicaslan, Barış; Ekmekci, Cenk; Solmaz, Hatice; Aslanturk, Omer F; Ozdogan, Oner

    2018-02-01

    Left bundle branch block (LBBB) causes a dyssynchronized contraction of left ventricle. This is a kind of regional wall-motion abnormality and measuring left ventricular ejection fraction (LVEF) by two-dimensional (2D) echocardiography could be less reliable in this particular condition. Our aim was to evaluate the role of dyssynchrony index (SDI), measured by three-dimensional (3D) echocardiography, in assessment of LVEF and left ventricular volumes accurately in patients with LBBB. In this case-control study, we included 52 of 64 enrolled participants (twelve participants with poor image quality were excluded) with LBBB and normal LVEF or nonischemic cardiomyopathy. Left ventricular ejection fraction (LVEF) and left ventricular volumes were assessed by 2D (modified Simpson's rule) and 3D (four beats full volume analysis) echocardiography and the impact of SDI on results were evaluated. In patients with SDI ≥6%, LVEF measurements were significantly different (46.00% [29.50-52.50] vs 37.60% [24.70-45.15], P < .001) between 2D and 3D echocardiography, respectively. In patients with SDI < 6%, there were no significant differences between two modalities in terms of LVEF measurements (54.50% [49.00-59.00] vs 54.25% [40.00-58.25], P = .193). LV diastolic volumes were not significantly different while systolic volumes were underestimated by 2D echocardiography, and this finding was more pronounced when SDI ≥ 6%. In patients with LBBB and high SDI (≥6%), LVEF values were overestimated and systolic volumes were underestimated by 2D echocardiography compared to 3D echocardiography. © 2017 Wiley Periodicals, Inc.

  11. Turn Allocation Patterns and Learning Opportunities

    ERIC Educational Resources Information Center

    Xie, Xiaoyan

    2011-01-01

    Drawing on data from three English classrooms at two Chinese universities, this paper documents the turn-taking patterns that the teachers and students developed over time and explores how these patterns affected students' opportunities to participate in classroom discourse. The data were collected through observations, audio- and video-taping,…

  12. RNA Tertiary Interactions in a Riboswitch Stabilize the Structure of a Kink Turn

    PubMed Central

    Schroeder, Kersten T.; Daldrop, Peter; Lilley, David M.J.

    2011-01-01

    Summary The kink turn is a widespread RNA motif that introduces an acute kink into the axis of duplex RNA, typically comprising a bulge followed by a G⋅A and A⋅G pairs. The kinked conformation is stabilized by metal ions, or the binding of proteins including L7Ae. We now demonstrate a third mechanism for the stabilization of k-turn structure, involving tertiary interactions within a larger RNA structure. The SAM-I riboswitch contains an essential standard k-turn sequence that kinks a helix so that its terminal loop can make a long-range interaction. We find that some sequence variations in the k-turn within the riboswitch do not prevent SAM binding, despite preventing the folding of the k-turn in isolation. Furthermore, two crystal structures show that the sequence-variant k-turns are conventionally folded within the riboswitch. This study shows that the folded structure of the k-turn can be stabilized by tertiary interactions within a larger RNA structure. PMID:21893284

  13. Right-Brained Kids in Left-Brained Schools

    ERIC Educational Resources Information Center

    Hunter, Madeline

    1976-01-01

    Students who learn well through left hemisphere brain input (oral and written) have minimal practice in using the right hemisphere, while those who are more proficient in right hemisphere (visual) input processing are handicapped by having to use primarily their left brains. (MB)

  14. Association between social capital and health-related quality of life among left behind and not left behind older people in rural China.

    PubMed

    Zhong, Yaqin; Schön, Pär; Burström, Bo; Burström, Kristina

    2017-12-16

    The association between social capital and health-related quality of life (HRQoL) has not been thoroughly studied among older persons in rural China, especially among those who were left behind or not. This study investigates the association between social capital and HRQoL and examines possible differences of this association between being left behind or not in rural China. A cross-sectional survey of 825 people aged 60 years and older, residing in three rural counties in Jiangsu Province in China, was conducted in 2013. Factor analysis was performed to measure social capital. EQ-5D was used to measure HRQoL. Tobit regression analysis with upper censoring was conducted to explore the association between social capital and EQ-5D index. After controlling for individual characteristics, low social capital and being left behind were significantly associated with low HRQoL. Old people with low social capital had 0.055 lower EQ-5D index compared to those with high social capital. Old people being left behind had 0.040 lower EQ-5D index compared to those who were not left behind. For different dimensions of social capital, the main effects came from the domain of trust and reciprocity. There was a significant interaction between low social capital and being left behind on HRQoL, suggesting that low social capital was associated with low HRQoL among persons left behind. Our findings indicate that the left behind old people with low social capital were a potentially vulnerable group in rural China. Formulating and implementing initiatives and strategies which increase social capital may foster better HRQoL, especially for old people who were left behind.

  15. Validation of semi-automatic segmentation of the left atrium

    NASA Astrophysics Data System (ADS)

    Rettmann, M. E.; Holmes, D. R., III; Camp, J. J.; Packer, D. L.; Robb, R. A.

    2008-03-01

    Catheter ablation therapy has become increasingly popular for the treatment of left atrial fibrillation. The effect of this treatment on left atrial morphology, however, has not yet been completely quantified. Initial studies have indicated a decrease in left atrial size with a concomitant decrease in pulmonary vein diameter. In order to effectively study if catheter based therapies affect left atrial geometry, robust segmentations with minimal user interaction are required. In this work, we validate a method to semi-automatically segment the left atrium from computed-tomography scans. The first step of the technique utilizes seeded region growing to extract the entire blood pool including the four chambers of the heart, the pulmonary veins, aorta, superior vena cava, inferior vena cava, and other surrounding structures. Next, the left atrium and pulmonary veins are separated from the rest of the blood pool using an algorithm that searches for thin connections between user defined points in the volumetric data or on a surface rendering. Finally, pulmonary veins are separated from the left atrium using a three dimensional tracing tool. A single user segmented three datasets three times using both the semi-automatic technique as well as manual tracing. The user interaction time for the semi-automatic technique was approximately forty-five minutes per dataset and the manual tracing required between four and eight hours per dataset depending on the number of slices. A truth model was generated using a simple voting scheme on the repeated manual segmentations. A second user segmented each of the nine datasets using the semi-automatic technique only. Several metrics were computed to assess the agreement between the semi-automatic technique and the truth model including percent differences in left atrial volume, DICE overlap, and mean distance between the boundaries of the segmented left atria. Overall, the semi-automatic approach was demonstrated to be repeatable within

  16. Turning Mechanics During Swimming by Oblate Hydromedusae

    NASA Astrophysics Data System (ADS)

    Costello, J.; Colin, S.; Sutherland, K.; Gemmell, B. J.

    2016-02-01

    Maneuverability is critical to the success of many species. Selective forces acting over millions of years have resulted in a range of capabilities currently unmatched by machines. Thus, understanding animal control of fluids for maneuvering has both biological and engineering applications. Medusae are radially symmetrical swimmers that must use asymmetric body motions to change direction during turning maneuvers. But what types of asymmetric motions are useful and how do they interact with surrounding fluids to generate rotational forces? We used high speed digital particle image velocimetry (DPIV) to investigate comparative swimming patterns of three hydromedusan species (Aequorea victoria, Clytia gregaria and Mitrocoma cellularia). We provide evidence for consistent animal-fluid interactions that underlie turning mechanics of oblate hydromedusae and provide new insights into the modulation and control of vorticity for low-speed animal maneuvering.

  17. Ultrasonically assisted turning of aviation materials: simulations and experimental study.

    PubMed

    Babitsky, V I; Mitrofanov, A V; Silberschmidt, V V

    2004-04-01

    Ultrasonically assisted turning of modern aviation materials is conducted with ultrasonic vibration (frequency f approximately 20 kHz, amplitude a approximately 15 microm) superimposed on the cutting tool movement. An autoresonant control system is used to maintain the stable nonlinear resonant mode of vibration throughout the cutting process. Experimental comparison of roughness and roundness for workpieces machined conventionally and with the superimposed ultrasonic vibration, results of high-speed filming of the turning process and nanoindentation analyses of the microstructure of the machined material are presented. The suggested finite-element model provides numerical comparison between conventional and ultrasonic turning of Inconel 718 in terms of stress/strain state, cutting forces and contact conditions at the workpiece/tool interface.

  18. Left-Wing Extremism: The Current Threat

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

    Karl A. Seger

    2001-04-30

    Left-wing extremism is ''alive and well'' both in the US and internationally. Although the current domestic terrorist threat within the U. S. is focused on right-wing extremists, left-wing extremists are also active and have several objectives. Leftist extremists also pose an espionage threat to U.S. interests. While the threat to the U.S. government from leftist extremists has decreased in the past decade, it has not disappeared. There are individuals and organizations within the U.S. who maintain the same ideology that resulted in the growth of left-wing terrorism in this country in the 1970s and 1980s. Some of the leaders frommore » that era are still communicating from Cuba with their followers in the U.S., and new leaders and groups are emerging.« less

  19. Turning the Page with Preconference Workshops

    ERIC Educational Resources Information Center

    Knowledge Quest, 2011

    2011-01-01

    For those who are experiencing a lack of creative inspiration within their school library program but are ready to "turn a page" in their career or school library program, they may head to Minneapolis to attend one of the many great preconference workshops. This article presents and describes preconference workshops design to rid…

  20. Interaction of the body, head, and eyes during walking and turning

    NASA Technical Reports Server (NTRS)

    Imai, T.; Moore, S. T.; Raphan, T.; Cohen, B.

    2001-01-01

    Body, head, and eye movements were measured in five subjects during straight walking and while turning corners. The purpose was to determine how well the head and eyes followed the linear trajectory of the body in space and whether head orientation followed changes in the gravito-inertial acceleration vector (GIA). Head and body movements were measured with a video-based motion analysis system and horizontal, vertical, and torsional eye movements with video-oculography. During straight walking, there was lateral body motion at the stride frequency, which was at half the frequency of stepping. The GIA oscillated about the direction of heading, according to the acceleration and deceleration associated with heel strike and toe flexion, and the body yawed in concert with stepping. Despite the linear and rotatory motions of the head and body, the head pointed along the forward motion of the body during straight walking. The head pitch/roll component appeared to compensate for vertical and horizontal acceleration of the head rather than orienting to the tilt of the GIA or anticipating it. When turning corners, subjects walked on a 50-cm radius over two steps or on a 200-cm radius in five to seven steps. Maximum centripetal accelerations in sharp turns were ca.0.4 g, which tilted the GIA ca.21 degrees with regard to the heading. This was anticipated by a roll tilt of the head of up to 8 degrees. The eyes rolled 1-1.5 degrees and moved down into the direction of linear acceleration during the tilts of the GIA. Yaw head deviations moved smoothly through the turn, anticipating the shift in lateral body trajectory by as much as 25 degrees. The trunk did not anticipate the change in trajectory. Thus, in contrast to straight walking, the tilt axes of the head and the GIA tended to align during turns. Gaze was stable in space during the slow phases and jumped forward in saccades along the trajectory, leading it by larger angles when the angular velocity of turning was greater

  1. Reciprocal Signaling between the Ectoderm and a Mesendodermal Left-Right Organizer Directs Left-Right Determination in the Sea Urchin Embryo

    PubMed Central

    Bessodes, Nathalie; Haillot, Emmanuel; Duboc, Véronique; Röttinger, Eric; Lahaye, François; Lepage, Thierry

    2012-01-01

    During echinoderm development, expression of nodal on the right side plays a crucial role in positioning of the rudiment on the left side, but the mechanisms that restrict nodal expression to the right side are not known. Here we show that establishment of left-right asymmetry in the sea urchin embryo relies on reciprocal signaling between the ectoderm and a left-right organizer located in the endomesoderm. FGF/ERK and BMP2/4 signaling are required to initiate nodal expression in this organizer, while Delta/Notch signaling is required to suppress formation of this organizer on the left side of the archenteron. Furthermore, we report that the H+/K+-ATPase is critically required in the Notch signaling pathway upstream of the S3 cleavage of Notch. Our results identify several novel players and key early steps responsible for initiation, restriction, and propagation of left-right asymmetry during embryogenesis of a non-chordate deuterostome and uncover a functional link between the H+/K+-ATPase and the Notch signaling pathway. PMID:23271979

  2. Alternative Fuels Data Center: City of Cincinnati Turns Sustainable Fleet

    Science.gov Websites

    Plan into On-Road Reality City of Cincinnati Turns Sustainable Fleet Plan into On-Road Reality Plan into On-Road Reality on Facebook Tweet about Alternative Fuels Data Center: City of Cincinnati Turns Sustainable Fleet Plan into On-Road Reality on Twitter Bookmark Alternative Fuels Data Center

  3. Assessment of Intrafraction Breathing Motion on Left Anterior Descending Artery Dose During Left-Sided Breast Radiation Therapy

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

    El-Sherif, Omar, E-mail: Omar.ElSherif@lhsc.on.ca; Department of Physics, London Regional Cancer Program, London, Ontario; Yu, Edward

    Purpose: To use 4-dimensional computed tomography (4D-CT) imaging to predict the level of uncertainty in cardiac dose estimates of the left anterior descending artery that arises due to breathing motion during radiation therapy for left-sided breast cancer. Methods and Materials: The fast helical CT (FH-CT) and 4D-CT of 30 left-sided breast cancer patients were retrospectively analyzed. Treatment plans were created on the FH-CT. The original treatment plan was then superimposed onto all 10 phases of the 4D-CT to quantify the dosimetric impact of respiratory motion through 4D dose accumulation (4D-dose). Dose-volume histograms for the heart, left ventricle (LV), and left anteriormore » descending (LAD) artery obtained from the FH-CT were compared with those obtained from the 4D-dose. Results: The 95% confidence interval of 4D-dose and FH-CT differences in mean dose estimates for the heart, LV, and LAD were ±0.5 Gy, ±1.0 Gy, and ±8.7 Gy, respectively. Conclusion: Fast helical CT is a good approximation for doses to the heart and LV; however, dose estimates for the LAD are susceptible to uncertainties that arise due to intrafraction breathing motion that cannot be ascertained without the additional information obtained from 4D-CT and dose accumulation. For future clinical studies, we suggest the use of 4D-CT–derived dose-volume histograms for estimating the dose to the LAD.« less

  4. In silico platform for predicting and initiating β-turns in a protein at desired locations.

    PubMed

    Singh, Harinder; Singh, Sandeep; Raghava, Gajendra P S

    2015-05-01

    Numerous studies have been performed for analysis and prediction of β-turns in a protein. This study focuses on analyzing, predicting, and designing of β-turns to understand the preference of amino acids in β-turn formation. We analyzed around 20,000 PDB chains to understand the preference of residues or pair of residues at different positions in β-turns. Based on the results, a propensity-based method has been developed for predicting β-turns with an accuracy of 82%. We introduced a new approach entitled "Turn level prediction method," which predicts the complete β-turn rather than focusing on the residues in a β-turn. Finally, we developed BetaTPred3, a Random forest based method for predicting β-turns by utilizing various features of four residues present in β-turns. The BetaTPred3 achieved an accuracy of 79% with 0.51 MCC that is comparable or better than existing methods on BT426 dataset. Additionally, models were developed to predict β-turn types with better performance than other methods available in the literature. In order to improve the quality of prediction of turns, we developed prediction models on a large and latest dataset of 6376 nonredundant protein chains. Based on this study, a web server has been developed for prediction of β-turns and their types in proteins. This web server also predicts minimum number of mutations required to initiate or break a β-turn in a protein at specified location of a protein. © 2015 Wiley Periodicals, Inc.

  5. A Retroaortic Left Renal Vein in a Female Cadaver.

    PubMed

    Fujishima, Yoshiko; Watanabe, Koichi; Tabira, Yoko; Iwanaga, Joe; Odo, Yui; Saga, Tsuyoshi; Tubbs, R Shane; Yamaki, Koh-Ichi

    2018-05-21

    We encountered a case of retroaortic left renal vein (RLRV) during an anatomical dissection course at our medical school in 2017. The case was a female cadaver who was 88 years old at death. Six roots of the left renal vein (RV) arose from the hilus of the kidney and joined to form one left renal vein, crossed dorsal to the abdominal aorta (AA) at the level of the second lumbar vertebra, and then drained into the inferior vena cava (IVC). Two roots joined at the right renal hilus to become the right RV to then drain into the IVC at the level of the first lumbar vertebral body. The reported frequency of RLRV is approximately 2%. Embryologically, the normal anastomosis of the left and right sub-cardinal veins results in the left RV traveling on the ventral surface of the AA. However, in the case presented here, the left RV traveled on the dorsal side of the AA due to the anastomosis of the left and right supra-cardinal veins and regression of the anastomosis between the left and right sub-cardinal veins. If both the dorsal and ventral anastomoses remain, the left RV travels on the dorsal and ventral sides of the aorta. Some of the clinical problems reported in association with RLRV are hematuria and abdominal pain, and the risk of damaging the RLRV during surgery of the posterior abdominal wall. Venous variants as reported herein should be kept in mind when interpreting imaging of the posterior abdominal wall or performing surgery or other invasive procedures near the RLRV.

  6. Patients with left bundle branch block and left axis deviation show a specific left ventricular asynchrony pattern: Implications for left ventricular lead placement during CRT implantation.

    PubMed

    Sciarra, Luigi; Golia, Paolo; Palamà, Zefferino; Scarà, Antonio; De Ruvo, Ermenegildo; Borrelli, Alessio; Martino, Anna Maria; Minati, Monia; Fagagnini, Alessandro; Tota, Claudia; De Luca, Lucia; Grieco, Domenico; Delise, Pietro; Calò, Leonardo

    Left bundle branch block (LBBB) and left axis deviation (LAD) patients may have poor response to resynchronization therapy (CRT). We sought to assess if LBBB and LAD patients show a specific pattern of mechanical asynchrony. CRT candidates with non-ischemic cardiomyopathy and LBBB were categorized as having normal QRS axis (within -30° and +90°) or LAD (within -30° and -90°). Patients underwent tissue Doppler imaging (TDI) to measure time interval between onset of QRS complex and peak systolic velocity in ejection period (Q-peak) at basal segments of septal, inferior, lateral and anterior walls, as expression of local timing of mechanical activation. Thirty patients (mean age 70.6years; 19 males) were included. Mean left ventricular ejection fraction was 0.28±0.06. Mean QRS duration was 172.5±13.9ms. Fifteen patients showed LBBB with LAD (QRS duration 173±14; EF 0.27±0.06). The other 15 patients had LBBB with a normal QRS axis (QRS duration 172±14; EF 0.29±0.05). Among patients with LAD, Q-peak interval was significantly longer at the anterior wall in comparison to each other walls (septal 201±46ms, inferior 242±58ms, lateral 267±45ms, anterior 302±50ms; p<0.0001). Conversely, in patients without LAD Q-peak interval was longer at lateral wall, when compared to each other (septal 228±65ms, inferior 250±64ms, lateral 328±98ms, anterior 291±86ms; p<0.0001). Patients with heart failure, presenting LBBB and LAD, show a specific pattern of ventricular asynchrony, with latest activation at anterior wall. This finding could affect target vessel selection during CRT procedures in these patients. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. How changes in top water bother big turning packs of up-going wet air

    NASA Astrophysics Data System (ADS)

    Wood, K.

    2017-12-01

    Big turning packs of up-going wet air form near areas of warm water at the top of big bodies of water. After these turning packs form, they usually get stronger if the top water stays warm. If the top water becomes less warm, the turning packs usually get less strong. Other things can change how strong a turning pack gets, like how wet the air around it is and if that air moves faster higher up than lower down. When these turning packs hit land, their rain and winds can hurt people and the stuff they own, especially if the turning pack is really strong. But it's hard to know how much stronger or less strong it will become before it hits land. Warm top water gives a turning pack of up-going wet air a lot of power, but cool top water doesn't, so we need to know how warm the top water is. Because I can't go into every turning pack myself, flying computers in outer space tell me what the top water is doing. I look at the top water near turning packs that get strong and see how it's different from the top water near those that get less strong. Top water that changes from warm to cool in a small area bothers a turning pack of up-going wet air, which then gets less strong. If we see these top water changes ahead of time, that might help us know what a turning pack will do before it gets close to land.

  8. Prediction of beta-turns in proteins using the first-order Markov models.

    PubMed

    Lin, Thy-Hou; Wang, Ging-Ming; Wang, Yen-Tseng

    2002-01-01

    We present a method based on the first-order Markov models for predicting simple beta-turns and loops containing multiple turns in proteins. Sequences of 338 proteins in a database are divided using the published turn criteria into the following three regions, namely, the turn, the boundary, and the nonturn ones. A transition probability matrix is constructed for either the turn or the nonturn region using the weighted transition probabilities computed for dipeptides identified from each region. There are two such matrices constructed for the boundary region since the transition probabilities for dipeptides immediately preceding or following a turn are different. The window used for scanning a protein sequence from amino (N-) to carboxyl (C-) terminal is a hexapeptide since the transition probability computed for a turn tetrapeptide is capped at both the N- and C- termini with a boundary transition probability indexed respectively from the two boundary transition matrices. A sum of the averaged product of the transition probabilities of all the hexapeptides involving each residue is computed. This is then weighted with a probability computed from assuming that all the hexapeptides are from the nonturn region to give the final prediction quantity. Both simple beta-turns and loops containing multiple turns in a protein are then identified by the rising of the prediction quantity computed. The performance of the prediction scheme or the percentage (%) of correct prediction is evaluated through computation of Matthews correlation coefficients for each protein predicted. It is found that the prediction method is capable of giving prediction results with better correlation between the percent of correct prediction and the Matthews correlation coefficients for a group of test proteins as compared with those predicted using some secondary structural prediction methods. The prediction accuracy for about 40% of proteins in the database or 50% of proteins in the test set is

  9. Universals and cultural variation in turn-taking in conversation

    PubMed Central

    Stivers, Tanya; Enfield, N. J.; Brown, Penelope; Englert, Christina; Hayashi, Makoto; Heinemann, Trine; Hoymann, Gertie; Rossano, Federico; de Ruiter, Jan Peter; Yoon, Kyung-Eun; Levinson, Stephen C.

    2009-01-01

    Informal verbal interaction is the core matrix for human social life. A mechanism for coordinating this basic mode of interaction is a system of turn-taking that regulates who is to speak and when. Yet relatively little is known about how this system varies across cultures. The anthropological literature reports significant cultural differences in the timing of turn-taking in ordinary conversation. We test these claims and show that in fact there are striking universals in the underlying pattern of response latency in conversation. Using a worldwide sample of 10 languages drawn from traditional indigenous communities to major world languages, we show that all of the languages tested provide clear evidence for a general avoidance of overlapping talk and a minimization of silence between conversational turns. In addition, all of the languages show the same factors explaining within-language variation in speed of response. We do, however, find differences across the languages in the average gap between turns, within a range of 250 ms from the cross-language mean. We believe that a natural sensitivity to these tempo differences leads to a subjective perception of dramatic or even fundamental differences as offered in ethnographic reports of conversational style. Our empirical evidence suggests robust human universals in this domain, where local variations are quantitative only, pointing to a single shared infrastructure for language use with likely ethological foundations. PMID:19553212

  10. Left-right asymmetry: cilia and calcium revisited.

    PubMed

    Blum, Martin; Vick, Philipp

    2015-03-02

    Leftward flow generated by motile cilia is known to underlie left-right asymmetry in vertebrate embryos. A new study now links intraciliary calcium oscillations to cilia motility and the downstream nodal signaling cascade that drives left-sided development. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. [Trauma induced left maxillary sinus dislocation of eyeball--a case report].

    PubMed

    Chen, Yu; Liu, Cuiping; Cui, Liping

    2013-01-01

    Patient male, 27 year old. Left facial and head trauma for 6 hours, due to motor vehicle accident. Patient state of mind was clear at arrival to hospital. Body temperature: 36C; Pulse: 80 Time/Minute; Breath: 20 Time/Minute; Blood pressure: 120/80 mm Hg. An irregular, horizontal laceration at arch of left eyebrow, approximately 8-10 cm. A laceration on left wing of nose skin, approximately 1 cm. A laceration also under lower eyelid skin of right eye, approximately 2 cm. Left blepharedema and enophthalmos. Orbital and nasal sinuses CT indications:contusion and laceration of the left frontal lobe of brain; fracture of the left orbital frontal, ethmoid, sphenoid bone, left nasal, maxillary sinus and zygoma with soft tissue contusion and laceration; the left eyeball and optic nerve sunk into the maxillary sinus (See figure 1). (1) Multiple orbital fractures; (2) Left maxillary sinus dislocation of eyeball; (3) The left frontal lobe contusion and laceration of brain.

  12. Left heart ventricular angiography

    MedlinePlus

    ... blood vessels. These x-ray pictures create a "movie" of the left ventricle as it contracts rhythmically. ... 22578925 www.ncbi.nlm.nih.gov/pubmed/22578925 . Review Date 9/26/2016 Updated by: Michael A. ...

  13. Left ventricular hypertrophy: virtuous intentions, malign consequences.

    PubMed

    Pokharel, Saraswati; Sharma, Umesh C; Pinto, Yigal M

    2003-06-01

    Left ventricular hypertrophy (LVH) is currently the focus of intense cardiovascular research, with the resultant rapid evolution of novel concepts relating to its exceedingly complex pathophysiology. In addition to the alterations in signal transduction and disturbances in Ca(2+) homeostasis, there are structural changes in myofilaments, disorganization of the cytoskeletal framework and increased collagen synthesis. LVH is associated with progressive left ventricular remodeling that culminates to heart failure. The modern treatment of left ventricular hypertrophy is now largely based on the hypothesis that neuroendocrine activation is important in the progression of the disease and inhibition of neurohormones is likely to have long-term benefit with regard to morbidity and mortality. Drugs specifically designed to unload the left ventricle, such as diuretics and vasodilators, appears to be less effective in reducing LV mass and improving prognosis. Thus, the evolution of treatment for LVH itself has provided much enlightenment for our understanding of the fundamental biology of the disorder.

  14. Investigation of flame driving and flow turning in axial solid rocket instabilities

    NASA Astrophysics Data System (ADS)

    Zinn, Ben T.; Daniel, Brady R.; Matta, Lawrence M.

    1993-08-01

    An understanding of the processes responsible for driving and damping acoustic oscillations in solid rocket motors is necessary for developing practical design methods that eliminate or reduce the occurrence combustion instabilities. While state of the art solid rocket stability prediction methods generally account for the flow turning loss, the magnitude and characteristics of this loss have never been fully investigated. Results of an investigation of the role of the flow turning loss in the stability of solid rockets and its dependence upon motor design and operating parameters are described. A one dimensional acoustic stability equation that verifies that the flow turning loss term is appropriately included in the one dimensional stability formulation was derived for a chamber with a constant mean temperature and pressure by an approach independent from that of Culick. This study was extended providing the background and expressions needed to guide an experimental study of the flow turning loss in the presence of mean temperature and density gradients. This allows the study of combustion systems in which mean temperature gradients and heat losses are significant. The relevant conservation equations were solved numerically for the experimental configuration in order to predict the behavior of the flow turning loss and to assist in the analysis of experimental results. Experiments performed, with and without combustion, showed that the flow turning loss strongly depends upon the propellant burning rate and the location of the flow turning region relative to the standing pressure wave.

  15. Turning Discovery Into Health – Asthma | NIH MedlinePlus the Magazine

    MedlinePlus

    ... of this page please turn Javascript on. Feature: Asthma Turning Discovery Into Health – Asthma Past Issues / Fall 2011 Table of Contents (Top ... show a cross-section of an airway during asthma symptoms and attack. CLICK IMAGE TO ENLARGE R ...

  16. Egg turning behavior and incubation temperature in Forster’s terns in relation to mercury contamination

    USGS Publications Warehouse

    Taylor, Gregory T.; Ackerman, Joshua T.; Shaffer, Scott A.

    2018-01-01

    Egg turning behavior is an important determinant of egg hatchability, but it remains relatively understudied. Here, we examined egg turning rates and egg temperatures in Forster’s terns (Sterna forsteri). We used artificial eggs containing a data logger with a 3-D accelerometer, a magnetometer, and a temperature thermistor to monitor parental incubation behavior of 131 tern nests. Overall, adults turned their eggs an average (±SD) of 3.8 ± 0.8 turns h-1, which is nearly two times higher than that of other seabirds. Egg turning rates increased with nest initiation date. We also examined egg turning rates and egg temperatures in relation to egg mercury contamination. Mercury contamination has been shown to be associated with reduced egg hatchability, and we hypothesized that mercury may decrease egg hatchability via altered egg turning behavior by parents. Despite the high variability in egg turning rates among individuals, the rate of egg turning was not related to mercury concentrations in sibling eggs. These findings highlight the need for further study concerning the potential determinants of egg turning behavior.

  17. Egg turning behavior and incubation temperature in Forster’s terns in relation to mercury contamination

    PubMed Central

    Ackerman, Joshua T.; Shaffer, Scott A.

    2018-01-01

    Egg turning behavior is an important determinant of egg hatchability, but it remains relatively understudied. Here, we examined egg turning rates and egg temperatures in Forster’s terns (Sterna forsteri). We used artificial eggs containing a data logger with a 3-D accelerometer, a magnetometer, and a temperature thermistor to monitor parental incubation behavior of 131 tern nests. Overall, adults turned their eggs an average (±SD) of 3.8 ± 0.8 turns h-1, which is nearly two times higher than that of other seabirds. Egg turning rates increased with nest initiation date. We also examined egg turning rates and egg temperatures in relation to egg mercury contamination. Mercury contamination has been shown to be associated with reduced egg hatchability, and we hypothesized that mercury may decrease egg hatchability via altered egg turning behavior by parents. Despite the high variability in egg turning rates among individuals, the rate of egg turning was not related to mercury concentrations in sibling eggs. These findings highlight the need for further study concerning the potential determinants of egg turning behavior. PMID:29447185

  18. Revascularization of Left Coronary System Using a Skeletonized Left Internal Mammary Artery - Sequential vs. Separate Grafting.

    PubMed

    Ji, Qiang; Shi, YunQing; Xia, LiMin; Ma, RunHua; Shen, JinQiang; Lai, Hao; Ding, WenJun; Wang, ChunSheng

    2017-12-25

    To evaluate in-hospital and mid-term outcomes of sequential vs. separate grafting of in situ skeletonized left internal mammary artery (LIMA) to the left coronary system in a single-center, propensity-matched study.Methods and Results:After propensity score-matching, 120 pairs of patients undergoing first scheduled isolated coronary artery bypass grafting (CABG) with in situ skeletonized LIMA grafting to the left anterior descending artery (LAD) territory were entered into a sequential group (sequential grafting of LIMA to the diagonal artery and then to the LAD) or a control group (separate grafting of LIMA to the LAD). The in-hospital and follow-up clinical outcomes and follow-up LIMA graft patency were compared. Both propensity score-matched groups had similar in-hospital and follow-up clinical outcomes. Sequential LIMA grafting was not found to be an independent predictor of adverse events. During a follow-up period of 27.0±7.3 months, 99.1% patency for the diagonal site and 98.3% for the LAD site were determined by coronary computed tomographic angiography after sequential LIMA grafting, both of which were similar with graft patency of separate grafting of in situ skeletonized LIMA to the LAD. Revascularization of the left coronary system using a skeletonized LIMA resulted in excellent in-hospital and mid-term clinical outcomes and graft patency using sequential grafting.

  19. Effects of sedation on echocardiographic variables of left atrial and left ventricular function in healthy cats.

    PubMed

    Ward, Jessica L; Schober, Karsten E; Fuentes, Virginia Luis; Bonagura, John D

    2012-10-01

    Although sedation is frequently used to facilitate patient compliance in feline echocardiography, the effects of sedative drugs on echocardiographic variables have been poorly documented. This study investigated the effects of two sedation protocols on echocardiographic indices in healthy cats, with special emphasis on the assessment of left atrial size and function, as well as left ventricular diastolic performance. Seven cats underwent echocardiography (transthoracic two-dimensional, spectral Doppler, color flow Doppler and tissue Doppler imaging) before and after sedation with both acepromazine (0.1 mg/kg IM) and butorphanol (0.25 mg/kg IM), or acepromazine (0.1 mg/kg IM), butorphanol (0.25 mg/kg IM) and ketamine (1.5 mg/kg IV). Heart rate increased significantly following acepromazine/butorphanol/ketamine (mean±SD of increase, 40±26 beats/min) and non-invasive systolic blood pressure decreased significantly following acepromazine/butorphanol (mean±SD of decrease, 12±19 mmHg). The majority of echocardiographic variables were not significantly different after sedation compared with baseline values. Both sedation protocols resulted in mildly decreased left ventricular end-diastolic dimension and mildly increased left ventricular end-diastolic wall thickness. This study therefore failed to demonstrate clinically meaningful effects of these sedation protocols on echocardiographic measurements, suggesting that sedation with acepromazine, butorphanol and/or ketamine can be used to facilitate echocardiography in healthy cats.

  20. Prediction of pi-turns in proteins using PSI-BLAST profiles and secondary structure information.

    PubMed

    Wang, Yan; Xue, Zhi-Dong; Shi, Xiao-Hong; Xu, Jin

    2006-09-01

    Due to the structural and functional importance of tight turns, some methods have been proposed to predict gamma-turns, beta-turns, and alpha-turns in proteins. In the past, studies of pi-turns were made, but not a single prediction approach has been developed so far. It will be useful to develop a method for identifying pi-turns in a protein sequence. In this paper, the support vector machine (SVM) method has been introduced to predict pi-turns from the amino acid sequence. The training and testing of this approach is performed with a newly collected data set of 640 non-homologous protein chains containing 1931 pi-turns. Different sequence encoding schemes have been explored in order to investigate their effects on the prediction performance. With multiple sequence alignment and predicted secondary structure, the final SVM model yields a Matthews correlation coefficient (MCC) of 0.556 by a 7-fold cross-validation. A web server implementing the prediction method is available at the following URL: http://210.42.106.80/piturn/.

  1. Behavioral evidence for left-hemisphere specialization of motor planning

    PubMed Central

    Meulenbroek, Ruud G. J.; Steenbergen, Bert

    2010-01-01

    Recent studies suggest that the left hemisphere is dominant for the planning of motor actions. This left-hemisphere specialization hypothesis was proposed in various lines of research, including patient studies, motor imagery studies, and studies involving neurophysiological techniques. However, most of these studies are primarily based on experiments involving right-hand-dominant participants. Here, we present the results of a behavioral study with left-hand-dominant participants, which follows up previous work in right-hand-dominant participants. In our experiment, participants grasped CD casings and replaced them in a different, pre-cued orientation. Task performance was measured by the end-state comfort effect, i.e., the anticipated degree of physical comfort associated with the posture that is planned to be adopted at movement completion. Both left- and right-handed participants showed stronger end-state comfort effects for their right hand compared to their left hand. These results lend behavioral support to the left-hemisphere-dominance motion-planning hypothesis. PMID:21184219

  2. Improving left spatial neglect through music scale playing.

    PubMed

    Bernardi, Nicolò Francesco; Cioffi, Maria Cristina; Ronchi, Roberta; Maravita, Angelo; Bricolo, Emanuela; Zigiotto, Luca; Perucca, Laura; Vallar, Giuseppe

    2017-03-01

    The study assessed whether the auditory reference provided by a music scale could improve spatial exploration of a standard musical instrument keyboard in right-brain-damaged patients with left spatial neglect. As performing music scales involves the production of predictable successive pitches, the expectation of the subsequent note may facilitate patients to explore a larger extension of space in the left affected side, during the production of music scales from right to left. Eleven right-brain-damaged stroke patients with left spatial neglect, 12 patients without neglect, and 12 age-matched healthy participants played descending scales on a music keyboard. In a counterbalanced design, the participants' exploratory performance was assessed while producing scales in three feedback conditions: With congruent sound, no-sound, or random sound feedback provided by the keyboard. The number of keys played and the timing of key press were recorded. Spatial exploration by patients with left neglect was superior with congruent sound feedback, compared to both Silence and Random sound conditions. Both the congruent and incongruent sound conditions were associated with a greater deceleration in all groups. The frame provided by the music scale improves exploration of the left side of space, contralateral to the right hemisphere, damaged in patients with left neglect. Performing a scale with congruent sounds may trigger at some extent preserved auditory and spatial multisensory representations of successive sounds, thus influencing the time course of space scanning, and ultimately resulting in a more extensive spatial exploration. These findings offer new perspectives also for the rehabilitation of the disorder. © 2015 The British Psychological Society.

  3. Effects of Frequent Hemodialysis on Ventricular Volumes and Left Ventricular Remodeling

    PubMed Central

    Greene, Tom; Chertow, Glenn M.; Kliger, Alan S.; Stokes, John B.; Beck, Gerald J.; Daugirdas, John T.; Kotanko, Peter; Larive, Brett; Levin, Nathan W.; Mehta, Ravindra L.; Rocco, Michael; Sanz, Javier; Yang, Phillip C.; Rajagopalan, Sanjay

    2013-01-01

    Summary Background and objectives Higher left ventricular volume is associated with death in patients with ESRD. This work investigated the effects of frequent hemodialysis on ventricular volumes and left ventricular remodeling. Design, setting, participants, & measurements The Frequent Hemodialysis Network daily trial randomized 245 patients to 12 months of six times per week versus three times per week in-center hemodialysis; the Frequent Hemodialysis Network nocturnal trial randomized 87 patients to 12 months of six times per week nocturnal hemodialysis versus three times per week predominantly home-based hemodialysis. Left and right ventricular end systolic and diastolic volumes, left ventricular mass, and ejection fraction at baseline and end of the study were ascertained by cardiac magnetic resonance imaging. The ratio of left ventricular mass/left ventricular end diastolic volume was used as a surrogate marker of left ventricular remodeling. In each trial, the effect of frequent dialysis on left or right ventricular end diastolic volume was tested between predefined subgroups. Results In the daily trial, frequent hemodialysis resulted in significant reductions in left ventricular end diastolic volume (−11.0% [95% confidence interval, −16.1% to −5.5%]), left ventricular end systolic volume (−14.8% [−22.7% to −6.2%]), right ventricular end diastolic volume (−11.6% [−19.0% to −3.6%]), and a trend for right ventricular end systolic volume (−11.3% [−21.4% to 0.1%]) compared with conventional therapy. The magnitude of reduction in left and right ventricular end diastolic volumes with frequent hemodialysis was accentuated among patients with residual urine output<100 ml/d (P value [interaction]=0.02). In the nocturnal trial, there were no significant changes in left or right ventricular volumes. The frequent dialysis interventions had no substantial effect on the ratio of left ventricular mass/left ventricular end diastolic volume in either

  4. Aortic valve replacement and tricuspid valve annuloplasty via a left thoracotomy in an adult with left pulmonary agenesis.

    PubMed

    Furutachi, Akira; Furukawa, Kojiro; Shimauchi, Kouta; Yunoki, Junji; Itoh, Manabu; Takamatsu, Masanori; Nogami, Eijiro; Mukae, Yosuke; Nishida, Takahiro

    2018-06-06

    We report a case of a 66-year-old man who was diagnosed with severe aortic regurgitation, moderate tricuspid regurgitation and chronic atrial fibrillation. Preoperative computed tomography showed left lung agenesis. We performed aortic valve replacement, tricuspid valve annuloplasty and right pulmonary vein isolation via a left thoracotomy. This approach provided an adequate field of view.

  5. Rare Anomalous Origin of Superior Left Pulmonary Artery from Left Subclavian Vein

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

    Lv, Tian-shi, E-mail: TerrenceLv@126.com; Wang, Chao, E-mail: wangchaoxs@163.com; Song, Li, E-mail: song9981@163.com

    2013-10-15

    We report for the first time an extremely rare anomalous origin of the superior left pulmonary artery in a 60 year-old man. Although it was occult in clinical indications, such a malformation still ought to be considered, especially during endovascular procedures.

  6. High explosive corner turning performance and the LANL mushroom test

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

    Hill, L.G.; Seitz, W.L.; Forest, C.A.

    1998-07-01

    The Mushroom test is designed to characterize the corner turning performance of a new generation of less sensitive booster explosives. The test is described in detail, and three corner turning figures-of-merit are examined using pure TATB (both Livermore{close_quote}s Ultrafine and a Los Alamos research blend) and PBX9504 as examples. {copyright} {ital 1998 American Institute of Physics.}

  7. Anatomical variations of the arterial pattern in the left hemiliver.

    PubMed

    Mlakar, Bostjan; Gadzijev, Eldar; Ravnik, Dean; Gvardijancic, Diana; Hribernik, Marija

    2002-04-01

    The arterial supply to the left hemiliver was studied in 70 liver casts. The arteries were divided into 15 groups according to their origin and branching pattern. The left hemiliver was supplied by one artery in 53% of cases, by two arteries in 40% and by three arteries in 7%. The left hepatic artery, which originated from the proper hepatic artery, supplied all three left segments in 39% of specimens. The replacing left hepatic artery, which originated from the left gastric artery, supplied the whole left hemiliver in 3% of cases. The incomplete, replacing left hepatic artery supplied segments 2, 3 and a part of segment 4 in 6% of cases, and only segments 2 and 3 in 11%. There was one segmental artery for segment 2 in 86%, and two in 14%. Segment 3 was supplied by one artery in 87%, and by two in 13%. Segment 4 was supplied by one artery in 39% of cases, by two arteries in 43%, by three in 14% and by four arteries in 4%.

  8. LEFT-RIGHT DIFFERENCES ON TIMED MOTOR EXAMINATION IN CHILDREN

    PubMed Central

    Roeder, Megan B.; Mahone, E. Mark; Larson, J. Gidley; Mostofsky, S. H.; Cutting, Laurie E.; Goldberg, Melissa C.; Denckla, Martha B.

    2008-01-01

    Age-related change in the difference between left- and right-side speed on motor examination may be an important indicator of maturation. Cortical maturation and myelination of the corpus callosum are considered to be related to increased bilateral skill and speed on timed motor tasks. We compared left minus right foot, hand, and finger speed differences using the Revised Physical and Neurological Assessment for Subtle Signs (PANESS; Denckla, 1985); examining 130 typically developing right-handed children (65 boys, 65 girls) ages 7−14. Timed tasks included right and left sets of 20 toe taps, 10 toe-heel alternation sequences, 20 hand pats, 10 hand pronate-supinate sets, 20 finger taps, and 5 sequences of each finger-to-thumb apposition. For each individual, six difference scores between left- and right-sided speeded performances of timed motor tasks were analyzed. Left-right differences decreased significantly with age on toe tapping, heel-toe alternations, hand pronation-supination, finger repetition, and finger sequencing. There were significant gender effects for heel-toe sequences (boys showing a greater left-right difference than girls), and a significant interaction between age and gender for hand pronation-supination, such that the magnitude of the left-right difference was similar for younger, compared with older girls, while the difference was significantly larger for younger, compared to older boys. Speed of performing right and left timed motor tasks equalizes with development; for some tasks, the equalization occurs earlier in girls than in boys. PMID:17852124

  9. Left-handedness and neurotic disturbances in adult urban population.

    PubMed

    Milenković, Sanja; Brkić, Milica; Belojević, Goran

    2013-01-01

    Controversial results on the relationship between the left-handedness and neurotic disturbances have been obtained in so far investigations. The aim of this study was to investigate the link between the left-handedness and neurotic disturbances in an adult urban population. A cross-sectional study was performed on 1,202 adult residents of the Stari Grad municipality in Belgrade, out of which 401 were males (33.4%) and 801 were females (66.6%). A questionnaire was used as an investigation instrument, with questions concerning age, gender, writing hand and neurotic disturbances: tension, agressiveness, anger, nervousness, weepiness and seclusion. Left-handedness was found in 60 subjects (5%) and it was statistically more frequent in males (7.7%) compared to females (3.6%) (p = 0.003). A decreasing trend of proportion of left-handed males was found in relation to aging. In the age group 18 to 39 years, agressiveness, as a specific neurotic disturbance, was significantly more frequent in left-handed males in comparison to right-handers (p = 0.035). In the age group 40 to 59 years, neurotic disturbances were more common among left-handed males compared to right-handers (p = 0.030).There were no significant diferences in the proportion of neurotic disturbances between the left-handed and the right-handed females. From a public health point of view, left-handed men may be regarded as a relatively vulnerable population category concerning mental health.

  10. Teachers Left behind by Common Core and No Child Left Behind

    ERIC Educational Resources Information Center

    Levitt, Roberta

    2017-01-01

    The enactment of the No Child Left Behind Act (2002) and the subsequent succession of legislative acts have had a profound impact on educational policy. An increased emphasis on teacher accountability and effectiveness led to the use of standardized test results to determine tangible rewards or punishments. In response, a culture of teaching to…

  11. Biliary tract variations of the left liver with special reference to the left medial sectional bile duct in 500 patients.

    PubMed

    Furusawa, Norihiko; Kobayashi, Akira; Yokoyama, Takahide; Shimizu, Akira; Motoyama, Hiroaki; Kanai, Keita; Arakura, Norikazu; Yamada, Akira; Kitou, Yoshihiro; Miyagawa, Shin-Ichi

    2015-08-01

    Among the intrahepatic bile ducts, the biliary system of the left medial sectional bile duct (B4) is known to have relatively complex patterns. The records of 500 patients who had been diagnosed as having hepato-pancreatico-biliary disease were retrospectively studied for anatomical biliary variations of the left liver with special reference to the drainage system of B4 using magnetic resonance images. The left hepatic duct was present in 494 patients (98.8%), whereas it was lacking in 6 patients (1.2%), and these patients exhibited the following B4 confluence patterns: B4 drained into the common hepatic duct in 2 patients (.4%), the right anterior sectional bile duct in 3 patients (.6%), and the right posterior sectional bile duct in 1 patient (.2%). The left hepatic duct was absent more frequently in patients with portal venous variations than in patients with a common branching pattern (8.2% vs .4%, P = .0011). The presently reported data are useful for obtaining a better understanding of the surgical anatomy of the biliary system of the left liver. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Printed Multi-Turn Loop Antenna for RF Bio-Telemetry

    NASA Technical Reports Server (NTRS)

    Simons, Rainee N.; Hall, David G.; Miranda, Felix A.

    2004-01-01

    In this paper, a novel printed multi-turn loop antenna for contact-less powering and RF telemetry from implantable bio- MEMS sensors at a design frequency of 300 MHz is demonstrated. In addition, computed values of input reactance, radiation resistance, skin effect resistance, and radiation efficiency for the printed multi-turn loop antenna are presented. The computed input reactance is compared with the measured values and shown to be in fair agreement. The computed radiation efficiency at the design frequency is about 24 percent.

  13. Alterations in left ventricular volumes induced by Valsalva manoeuvre

    NASA Technical Reports Server (NTRS)

    Brooker, J. Z.; Alderman, E. L.; Harrison, D. C.

    1974-01-01

    Five patients were studied with left ventriculography during different phases of the Valsalva manoeuvre. Small doses of contrast medium allowed adequate repetitive visualization of the left ventricle for volume calculation. During strain phase, the volume of the left ventricle decreased by nearly 50 per cent in each case, and stroke volume and cardiac output also dropped strikingly. Release of straining was attended by a sharp rebound of left ventricular volume to control levels, with a transient surge of increased cardiac output 42 per cent above that of the resting state.

  14. Etiological aspect of left-handedness in adolescents.

    PubMed

    Dragović, Milan; Milenković, Sanja; Kocijancić, Dusica; Zlatko, Sram

    2013-01-01

    Lateralization of brain functions such as language and manual dominance (hand preferences and fine motor control) are most likely under genetic control. However, this does not preclude the effect of various environmental factors on functional brain lateralization. A strong association of non-right-handedness (left- and mixed-handedness) with various neurodevelopmental conditions (e.g. schizophrenia, autism, Rett syndrome) implies that in some cases, non-right-handedness may be acquired rather than inherited (i.e., pathologically determined). The aim of the study was: (a) re-investigation of several known risk factors for left-handedness (age of mother and/or father, twin pregnancies, and birth order), and (b) examination of hitherto uninvestigated factors (type of birth, Apgar score, maternal smoking during pregnancy). Putative, causative environmental agents for this shift in manual distributions are explored in a sample of 1031 high school students (404 males and 627 females) from Belgrade. Both pre-existing (age of parents, twin pregnancy, and birth order) and new (Apgar score, maternal smoking, type of birth) putative agents are examined. We found that maternal smoking and low Apgar score (2-6) can significantly increase risk for left-handedness (p=0.046 and p=0.042, respectively).The remaining factors showed no significant association with left-handedness in adolescents. Our study clearly demonstrates that left-handedness may be related to maternal smoking during pregnancy and a low Apgar score on birth.

  15. Modification of Impulse Generation During Pirouette Turns With Increased Rotational Demands.

    PubMed

    Zaferiou, Antonia M; Wilcox, Rand R; McNitt-Gray, Jill L

    2016-10-01

    This study determined how dancers regulated angular and linear impulse during the initiation of pirouettes of increased rotation. Skilled dancers (n = 11) performed single and double pirouette turns with each foot supported by a force plate. Linear and angular impulses generated by each leg were quantified and compared between turn types using probability-based statistical methods. As rotational demands increased, dancers increased the net angular impulse generated. The contribution of each leg to net angular impulse in both single and double pirouettes was influenced by stance configuration strategies. Dancers who generated more angular impulse with the push leg than with the turn leg initiated the turn with the center of mass positioned closer to the turn leg than did other dancers. As rotational demands increased, dancers tended to increase the horizontal reaction force magnitude at one or both feet; however, they used subject-specific mechanisms. By coordinating the generation of reaction forces between legs, changes in net horizontal impulse remained minimal, despite impulse regulation at each leg used to achieve more rotations. Knowledge gained regarding how an individual coordinates the generation of linear and angular impulse between both legs as rotational demand increased can help design tools to improve that individual's performance.

  16. Left main coronary artery disease: pathophysiology, diagnosis, and treatment.

    PubMed

    Collet, Carlos; Capodanno, Davide; Onuma, Yoshinobu; Banning, Adrian; Stone, Gregg W; Taggart, David P; Sabik, Joseph; Serruys, Patrick W

    2018-06-01

    The advent of coronary angiography in the 1960s allowed for the risk stratification of patients with stable angina. Patients with unprotected left main coronary artery disease have an increased risk of death related to the large amount of myocardium supplied by this vessel. Although coronary angiography remains the preferred imaging modality for the evaluation of left main coronary artery stenosis, this technique has important limitations. Angiograms of the left main coronary artery segment can be difficult to interpret, and almost one-third of patients can be misclassified when fractional flow reserve is used as the reference. In patients with clinically significant unprotected left main coronary artery disease, surgical revascularization was shown to improve survival compared with medical therapy and has been regarded as the treatment of choice for unprotected left main coronary artery disease. Two large-scale clinical trials published in 2016 support the usefulness of catheter-based revascularization in selected patients with unprotected left main coronary artery disease. In this Review, we describe the pathophysiology of unprotected left main coronary artery disease, discuss diagnostic approaches in light of new noninvasive and invasive imaging techniques, and detail risk stratification models to aid the Heart Team in the decision-making process for determining the best revascularization strategy for these patients.

  17. Early development of turn-taking with parents shapes vocal acoustics in infant marmoset monkeys

    PubMed Central

    Takahashi, Daniel Y.; Fenley, Alicia R.; Ghazanfar, Asif A.

    2016-01-01

    In humans, vocal turn-taking is a ubiquitous form of social interaction. It is a communication system that exhibits the properties of a dynamical system: two individuals become coupled to each other via acoustic exchanges and mutually affect each other. Human turn-taking develops during the first year of life. We investigated the development of vocal turn-taking in infant marmoset monkeys, a New World species whose adult vocal behaviour exhibits the same universal features of human turn-taking. We find that marmoset infants undergo the same trajectory of change for vocal turn-taking as humans, and do so during the same life-history stage. Our data show that turn-taking by marmoset infants depends on the development of self-monitoring, and that contingent parental calls elicit more mature-sounding calls from infants. As in humans, there was no evidence that parental feedback affects the rate of turn-taking maturation. We conclude that vocal turn-taking by marmoset monkeys and humans is an instance of convergent evolution, possibly as a result of pressures on both species to adopt a cooperative breeding strategy and increase volubility. PMID:27069047

  18. Long-term outcome after percutaneous closure of persistent left superior caval vein draining into the left atrium: a contrast-enhanced CT study.

    PubMed

    Marini, Davide; Castagno, Matteo; Millesimo, Michele; Ferroni, Francesca; Ferraro, Gaetana; Pace Napoleone, Carlo; Agnoletti, Gabriella

    2017-10-01

    Data regarding long-term outcome after percutaneous closure of left superior caval vein draining into the left atrium are lacking. The aim of the present study was to report the long-term follow-up by using contrast-enhanced CT. In all, three patients underwent percutaneous closure of left superior caval vein draining into the left atrium between 2005 and 2015. All of them were evaluated clinically and underwent contrast-enhanced CT. In one patient, the Amplatzer® Septal Occluder was used. In two patients, the Amplatzer® Vascular Plug type-1 was preferred: the device size/LSVC diameter ratio was 1.7 in the child and 1.2 in the adult. There were no early-onset or long-term onset complications. CT was performed 1, 2, and 10 years after the procedure, respectively. Complete occlusion of the vessel was documented in all. After 10 years since the procedure, CT revealed a persistent trivial residual shunt through the accessory hemiazygos vein in one patient, in whom the device was implanted above its drainage into the left superior caval vein. When an Amplatzer® Vascular Plug type-1 is oversized compared with the venous vessel diameter, it immediately assumes a dog-bone shape that disappears early to regain its shape memory and nominal size. Percutaneous occlusion of left superior caval vein draining into the left atrium has excellent early and long-term outcomes. The optimal implantation of the device is below the drainage of the accessory hemiazygos vein, when present. The device might be oversized compared with the left superior caval vein diameter according to the age of the patient.

  19. Diamond turning of thermoplastic polymers

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

    Smith, E.; Scattergood, R.O.

    Single point diamond turning studies were made using a series of thermoplastic polymers with different glass transition temperatures. Variations in surface morphology and surface roughness were observed as a function of cutting speed. Lower glass transition temperatures facilitate smoother surface cuts and better surface finish. This can be attributed to the frictional heating that occurs during machining. Because of the very low glass transition temperatures in polymeric compared to inorganic glasses, the precision machining response can be very speed sensitive.

  20. Design of Choking Cascade Turns.

    DTIC Science & Technology

    1982-12-01

    L D-R124 792 DESIGN OF CHOK~ING CASCADE TURNSCU) AIR FORCE INST OF v TECH MRIGHT-PAT1TERSON AFB OH SCHOOL OF ENGINEERING J BAIRD DEC 82 AFIT/GRE/AA...82D- 3 DESIGN OF CHOKING *’ CASCADE TURNS THESIS Presented to the Faculty of the School of Enqineerinq of the Air Force Institute of Technoloqy Air ...Approved for public release; distribution unlimited 4* Preface Ramjet engines are being considered by both the Air Force and Navy for tactical air