Defense.gov Special Report: World War II: Turning Points

Science.gov Websites

Department of Defense Submit Search Turning points of World War II U.S. Marines rest in the field on landed several miles from his intended drop zone. Cook, 87, was among the handful of World War II -Day U.S. and Allied military veterans of World War II and contemporay warriors attended commemoration

Probabilistic Magnetotelluric Inversion with Adaptive Regularisation Using the No-U-Turns Sampler

NASA Astrophysics Data System (ADS)

Conway, Dennis; Simpson, Janelle; Didana, Yohannes; Rugari, Joseph; Heinson, Graham

2018-04-01

We present the first inversion of magnetotelluric (MT) data using a Hamiltonian Monte Carlo algorithm. The inversion of MT data is an underdetermined problem which leads to an ensemble of feasible models for a given dataset. A standard approach in MT inversion is to perform a deterministic search for the single solution which is maximally smooth for a given data-fit threshold. An alternative approach is to use Markov Chain Monte Carlo (MCMC) methods, which have been used in MT inversion to explore the entire solution space and produce a suite of likely models. This approach has the advantage of assigning confidence to resistivity models, leading to better geological interpretations. Recent advances in MCMC techniques include the No-U-Turns Sampler (NUTS), an efficient and rapidly converging method which is based on Hamiltonian Monte Carlo. We have implemented a 1D MT inversion which uses the NUTS algorithm. Our model includes a fixed number of layers of variable thickness and resistivity, as well as probabilistic smoothing constraints which allow sharp and smooth transitions. We present the results of a synthetic study and show the accuracy of the technique, as well as the fast convergence, independence of starting models, and sampling efficiency. Finally, we test our technique on MT data collected from a site in Boulia, Queensland, Australia to show its utility in geological interpretation and ability to provide probabilistic estimates of features such as depth to basement.

Loss of G-A base pairs is insufficient for achieving a large opening of U4 snRNA K-turn motif.

PubMed

Cojocaru, Vlad; Klement, Reinhard; Jovin, Thomas M

2005-01-01

Upon binding to the 15.5K protein, two tandem-sheared G-A base pairs are formed in the internal loop of the kink-turn motif of U4 snRNA (Kt-U4). We have reported that the folding of Kt-U4 is assisted by protein binding. Unstable interactions that contribute to a large opening of the free RNA ('k-e motion') were identified using locally enhanced sampling molecular dynamics simulations, results that agree with experiments. A detailed analysis of the simulations reveals that the k-e motion in Kt-U4 is triggered both by loss of G-A base pairs in the internal loop and backbone flexibility in the stems. Essential dynamics show that the loss of G-A base pairs is correlated along the first mode but anti-correlated along the third mode with the k-e motion. Moreover, when enhanced sampling was confined to the internal loop, the RNA adopted an alternative conformation characterized by a sharper kink, opening of G-A base pairs and modified stacking interactions. Thus, loss of G-A base pairs is insufficient for achieving a large opening of the free RNA. These findings, supported by previously published RNA structure probing experiments, suggest that G-A base pair formation occurs upon protein binding, thereby stabilizing a selective orientation of the stems.

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.

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

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.

Head-to-head comparison of intensive lifestyle intervention (U-TURN) versus conventional multifactorial care in patients with type 2 diabetes: protocol and rationale for an assessor-blinded, parallel group and randomised trial

PubMed Central

Ried-Larsen, Mathias; Hansen, Katrine B; Johansen, Mette Y; Pedersen, Maria; Zacho, Morten; Hansen, Louise S; Kofoed, Katja; Thomsen, Katja; Jensen, Mette S; Nielsen, Rasmus O; MacDonald, Chris; Langberg, Henning; Vaag, Allan A; Pedersen, Bente K; Karstoft, Kristian

2015-01-01

Introduction Current pharmacological therapies in patients with type 2 diabetes (T2D) are challenged by lack of sustainability and borderline firm evidence of real long-term health benefits. Accordingly, lifestyle intervention remains the corner stone in the management of T2D. However, there is a lack of knowledge regarding the optimal intervention programmes in T2D ensuring both compliance as well as long-term health outcomes. Our objective is to assess the effects of an intensive lifestyle intervention (the U-TURN intervention) on glycaemic control in patients with T2D. Our hypothesis is that intensive lifestyle changes are equally effective as standard diabetes care, including pharmacological treatment in maintaining glycaemic control (ie, glycated haemoglobin (HbA1c)) in patients with T2D. Furthermore, we expect that intensive lifestyle changes will decrease the need for antidiabetic medications. Methods and analysis The study is an assessor-blinded, parallel group and a 1-year randomised trial. The primary outcome is change in glycaemic control (HbA1c), with the key secondary outcome being reductions in antidiabetic medication. Participants will be patients with T2D (T2D duration <10 years) without complications who are randomised into an intensive lifestyle intervention (U-TURN) or a standard care intervention in a 2:1 fashion. Both groups will be exposed to the same standardised, blinded, target-driven pharmacological treatment and can thus maintain, increase, reduce or discontinue the pharmacological treatment. The decision is based on the standardised algorithm. The U-TURN intervention consists of increased training and basal physical activity level, and an antidiabetic diet including an intended weight loss. The standard care group as well as the U-TURN group is offered individual diabetes management counselling on top of the pharmacological treatment. Ethics and dissemination This study has been approved by the Scientific Ethical Committee at the

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)

Education, Inc.: Turning Learning into a Business. Revised Edition.

ERIC Educational Resources Information Center

Kohn, Alfie, Ed.; Shannon, Patrick, Ed.

This collection of essays builds a case against those who see children as customers or workers and those who want to turn learning into a business. Following an introduction, The 500-Pound Gorilla by Alfie Kohn, section 1, Commercialism in Schools, contains: (1) Buy Me! Buy Me! (Alex Molnar and Joseph A. Reaves); (2) Commercialism in U.S. Schools…

Determination of 235U/238U Ratio on Urine by ICP-MS

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

Collins, L; Gobaleza, A; Langston, R

2011-10-19

LLNL Internal Dosimetry Program - The new procedure satisfies the requirement to determine {sup 235}U/{sup 238}U ratio in bioassay urine samples. MDA - The L{sub C} and MDA{sub 95} for {sup 235}U are well below the required detection limit of 0.00035 {mu}g/L. Turn around time - Analysis of 10 samples plus 2 QCs can be completed in one work day (8 hours).

Bank-to-Turn Cruise Missile Terminal Guidance and Control Law Comparison.

DTIC Science & Technology

1983-06-01

Me. aboma sae ,.i to 8"leeiSWwm ** f Rewe) .I SUPPLI01MENTARV MOTEU It. KEy WORM Cr# a OOWm@ &&. #1 00@00@Wp ad UEW~fltgp eek MrnS.) Bank-To-Turn...IIUI’ IUtfl- 0o 9 .- I % e*IPo’%LU3 0-0’-.j% o7U. ’ U k.246 "’. 4140 0-SW 4&6 6 J~ 1"IJ~ 1 LA t Lurnp-68’Ol- 00 goN44. 4S II- 03 t--0 - ’.0 stU oc o*3...0 1 U’- 0 1- U~- 04 3 t- .- 0 0 01 0.0 4140 3’ W 4O’J40 40404.040177( * 0 .0oOZ .0 4U. JJ~* ~1ZNZ ..00ZO~O000UnowZ -- a 0 0 3 * 0 e0-a0 3 % Z 14 01

Electroosmotic flow analysis of a branched U-turn nanofluidic device.

PubMed

Parikesit, Gea O F; Markesteijn, Anton P; Kutchoukov, Vladimir G; Piciu, Oana; Bossche, Andre; Westerweel, Jerry; Garini, Yuval; Young, Ian T

2005-10-01

In this paper, we present the analysis of electroosmotic flow in a branched -turn nanofluidic device, which we developed for detection and sorting of single molecules. The device, where the channel depth is only 150 nm, is designed to optically detect fluorescence from a volume as small as 270 attolitres (al) with a common wide-field fluorescent setup. We use distilled water as the liquid, in which we dilute 110 nm fluorescent beads employed as tracer-particles. Quantitative imaging is used to characterize the pathlines and velocity distribution of the electroosmotic flow in the device. Due to the device's complex geometry, the electroosmotic flow cannot be solved analytically. Therefore we use numerical flow simulation to model our device. Our results show that the deviation between measured and simulated data can be explained by the measured Brownian motion of the tracer-particles, which was not incorporated in the simulation.

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.

Wofford-Thornburgh: a turning point for health reform.

PubMed

Tokarski, C

1992-01-01

The November 5 special election in Pennsylvania pitting appointed Senator Harris Wofford against former U.S. Attorney General Richard Thornburgh was a turning point in the national debate over health reform. Under the glare of media spotlights, Wofford mounted a come-from-behind victory over the heavily favored Thornburgh by trumpeting "national health insurance." Since Wofford's victory, President Bush has rethought his previous indifference to health reform and promised to announce a comprehensive plan in January, more than a year ahead of schedule.

In-pile test results of U-silicide or U-nitride coated U-7Mo particle dispersion fuel in Al

NASA Astrophysics Data System (ADS)

Kim, Yeon Soo; Park, J. M.; Lee, K. H.; Yoo, B. O.; Ryu, H. J.; Ye, B.

2014-11-01

U-silicide or U-nitride coated U-Mo particle dispersion fuel in Al (U-Mo/Al) was in-pile tested to examine the effectiveness of the coating as a diffusion barrier between the U-7Mo fuel kernels and Al matrix. This paper reports the PIE data and analyses focusing on the effectiveness of the coating in terms of interaction layer (IL) growth and general fuel performance. The U-silicide coating showed considerable success, but it also provided evidence for additional improvement for coating process. The U-nitride coated specimen showed largely inefficient results in reducing IL growth. From the test, important observations were also made that can be utilized to improve U-Mo/Al fuel performance. The heating process for coating turned out to be beneficial to suppress fuel swelling. The use of larger fuel particles confirmed favorable effects on fuel performance.

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.

Hinge-Like Motions in RNA Kink-Turns: The Role of the Second A-Minor Motif and Nominally Unpaired Bases

PubMed Central

Rázga, Filip; Koča, Jaroslav; Šponer, Jiří; Leontis, Neocles B.

2005-01-01

Kink-turn (K-turn) motifs are asymmetric internal loops found at conserved positions in diverse RNAs, with sharp bends in phosphodiester backbones producing V-shaped structures. Explicit-solvent molecular dynamics simulations were carried out for three K-turns from 23S rRNA, i.e., Kt-38 located at the base of the A-site finger, Kt-42 located at the base of the L7/L12 stalk, and Kt-58 located in domain III, and for the K-turn of human U4 snRNA. The simulations reveal hinge-like K-turn motions on the nanosecond timescale. The first conserved A-minor interaction between the K-turn stems is entirely stable in all simulations. The angle between the helical arms of Kt-38 and Kt-42 is regulated by local variations of the second A-minor (type I) interaction between the stems. Its variability ranges from closed geometries to open ones stabilized by insertion of long-residency waters between adenine and cytosine. The simulated A-minor geometries fully agree with x-ray data. Kt-58 and Kt-U4 exhibit similar elbow-like motions caused by conformational change of the adenosine from the nominally unpaired region. Despite the observed substantial dynamics of K-turns, key tertiary interactions are stable and no sign of unfolding is seen. We suggest that some K-turns are flexible elements mediating large-scale ribosomal motions during the protein synthesis cycle. PMID:15722438

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.

7 CFR 51.1001 - U.S. Combination.

Code of Federal Regulations, 2012 CFR

2012-01-01

... the color requirements of the U.S. No. 1 grade and the U.S. No. 2 limes shall meet the color... grade requirements only because of blanching shall be designated as “U.S. Combination, Mixed Color”: And... Color grade requirements only because of turning yellow or yellow color, caused by the ripening process...

Leadership or Hegemony Investigating U.S. Command of the Sea and Implications for U.S. Grand Strategy

DTIC Science & Technology

acknowledged command of the global commons. At the turn of the 21st century, the U.S. was fully dominant in its command of sea and space, and largely... sea ; offers implications for naval doctrine, strategy, and acquisitions; and provides vital lessons to inform U.S. grand strategy.

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.

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

Structure of a rare non-standard sequence k-turn bound by L7Ae protein

PubMed Central

Huang, Lin; Lilley, David M.J.

2014-01-01

Kt-23 from Thelohania solenopsae is a rare RNA kink turn (k-turn) where an adenine replaces the normal guanine at the 2n position. L7Ae is a member of a strongly conserved family of proteins that bind a range of k-turn structures in the ribosome, box C/D and H/ACA small nucleolar RNAs and U4 small nuclear RNA. We have solved the crystal structure of T. solenopsae Kt-23 RNA bound to Archeoglobus fulgidus L7Ae protein at a resolution of 2.95 Å. The protein binds in the major groove displayed on the outer face of the k-turn, in a manner similar to complexes with standard k-turn structures. The k-turn adopts a standard N3 class conformation, with a single hydrogen bond from A2b N6 to A2n N3. This contrasts with the structure of the same sequence located in the SAM-I riboswitch, where it adopts an N1 structure, showing the inherent plasticity of k-turn structure. This potentially can affect any tertiary interactions in which the RNA participates. PMID:24482444

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).

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...

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.

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.

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.

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.

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.

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.

48 CFR 3036.104-90 - Authority for one-step turn-key design-build contracting for the United States Coast Guard (USCG).

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 7 2010-10-01 2010-10-01 false Authority for one-step... General 3036.104-90 Authority for one-step turn-key design-build contracting for the United States Coast Guard (USCG). The Head of the Contracting Activity (HCA) of the U.S. Coast Guard may use one-step turn...

Chiral mutagenesis of insulin. Contribution of the B20-B23 beta-turn to activity and stability.

PubMed

Nakagawa, Satoe H; Hua, Qing-xin; Hu, Shi-Quan; Jia, Wenhua; Wang, Shuhua; Katsoyannis, Panayotis G; Weiss, Michael A

2006-08-04

Insulin contains a beta-turn (residues B20-B23) interposed between two receptor-binding elements, the central alpha-helix of the B chain (B9-B19) and its C-terminal beta-strand (B24-B28). The turn contains conserved glycines at B20 and B23. Although insulin exhibits marked conformational variability among crystal forms, these glycines consistently maintain positive phi dihedral angles within a classic type-I beta-turn. Because the Ramachandran conformations of GlyB20 and GlyB23 are ordinarily forbidden to L-amino acids, turn architecture may contribute to structure or function. Here, we employ "chiral mutagenesis," comparison of corresponding D- and L-Ala substitutions, to investigate this turn. Control substitutions are introduced at GluB21, a neighboring residue exhibiting a conventional (negative) phi angle. The D- and L-Ala substitutions at B23 are associated with a marked stereospecific difference in activity. Whereas the D-AlaB23 analog retains native activity, the L analog exhibits a 20-fold decrease in receptor binding. By contrast, D- and L-AlaB20 analogs each exhibit high activity. Stereospecific differences between the thermodynamic stabilities of the analogs are nonetheless more pronounced at B20 (delta deltaG(u) 2.0 kcal/mole) than at B23 (delta deltaG(u) 0.7 kcal/mole). Control substitutions at B21 are well tolerated without significant stereospecificity. Chiral mutagenesis thus defines the complementary contributions of these conserved glycines to protein stability (GlyB20) or receptor recognition (GlyB23).

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.

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).

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.

When the tables are turned: The effects of the 2016 U.S. Presidential election on in-group favoritism and out-group hostility

PubMed Central

Bashshur, Michael R.

2018-01-01

The outcome of the 2016 U.S. Presidential election was a big surprise to many, as the majority of polls had predicted the opposite outcome. In this two-stage cross-sectional study, we focus on how Democrats and Republicans reacted to this electoral surprise and how these reactions might have influenced the way they allocated resources to each other in small groups. We find that, before the election, Republicans showed greater in-group favoritism than Democrats, who treated others equally, regardless of their political affiliation. We then show that Democrats experienced the election outcome as an ego shock and, in the week following the election, reported significantly higher levels of negative emotions and lower levels of self-esteem than Republicans. These reactions then predicted how individuals’ decided to allocate resources to others: after the election, Republicans no longer showed in-group favoritism, while Democrats showed out-group derogation. We find these decisions when the tables were turned can be partially explained by differences in participants’ state self-esteem. PMID:29795642

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

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.

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.

Reductions without Regret: Avoiding Wrong Turns, Roach Motels, and Box Canyons

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

Swegle, John A.; Tincher, Douglas J.

This is the third of three papers (in addition to an introductory summary) aimed at providing a framework for evaluating future reductions or modifications of the U.S. nuclear force, first by considering previous instances in which nuclear-force capabilities were eliminated; second by looking forward into at least the foreseeable future at the features of global and regional deterrence (recognizing that new weapon systems currently projected will have expected lifetimes stretching beyond our ability to predict the future); and third by providing examples of past or possible undesirable outcomes in the shaping of the future nuclear force, as well as somemore » closing thoughts for the future. In this paper, we provide one example each of our judgments on what constitutes a box canyon, a roach motel, and a wrong turn: Wrong Turn: The Reliable Replacement Warhead: Roach Motel: SRAM T vs the B61: and A Possible Box Canyon: A Low-Yield Version of the W76 SLBM Warhead. Recognizing that new nuclear missions or weapons are not demanded by current circumstances ₋ a development path that yields future capabilities similar to those of today, which are adequate if not always ideal, and a broader national-security strategy that supports nonproliferation and arms control by reducing the role for, and numbers, of nuclear weapons ₋ we briefly consider alternate, less desirable futures, and their possible effect on the complex problem of regional deterrence. In this regard, we discuss the issues posed by, and possible responses to, three example regional deterrence challenges: in-country defensive use of nuclear weapons by an adversary; reassurance of U.S. allies with limited strategic depth threatened by an emergent nuclear power; and extraterritorial, non-strategic offensive use of nuclear weapons by an adversary in support of limited military objectives against a U.S. ally.« less

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.

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.

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...

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...

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...

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.

U-Turn to Prosperity

ERIC Educational Resources Information Center

Zhao, Yong

2013-01-01

The road to success in the new world economy requires more creative thinkers, innovators, and entrepreneurs than ever before. Why is the United States going in the wrong direction? Thanks to globalization and technological advancement, traditional middle-class jobs, such as manufacturing, have been disappearing quickly, offshored to other…

The Big U-Turn

ERIC Educational Resources Information Center

Hassel, Emily Ayscue; Hassel, Bryan C.

2009-01-01

This article explains what the authors know, from plentiful cross-sector research, about how to engineer turnarounds within existing organizations. It then identifies two critical policy issues that states and districts must address to accelerate the prevalence of real, successful turnarounds in education. Effective turnaround leaders follow a…

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.

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.

Looking back on rear-facing car seats: Surveying U.S. parents in 2011 and 2013

PubMed Central

Macy, Michelle L.; Butchart, Amy T.; Singer, Dianne C.; Gebremariam, Achamyeleh; Clark, Sarah J.; Davis, Matthew M.

2015-01-01

Objectives We sought to determine the age at which U.S. parents first turned their child’s car seat to face forward and information sources used to make that decision at the time of the release of the 2011 guidelines for child passenger safety and 30 months later. Methods Two separate cross-sectional Web-based surveys of nationally representative panels of U.S. parents, May 2011 and November 2013. Survey participation rate was 54% in both years. Parents of children ≤4 years old responded to questions about transitioning from rear-facing to forward-facing car seats (n=495 in 2011; n=521 in 2013). Results In 2011, 33% of parents of 1-to 4-year-old children who had been turned to face forward (n=409) turned at or before 12 months and 16% turned at 2 years or older. In 2013, 24% of parents of 1- to 4-year-old children who had been turned to face forward (n=413) turned at or before 12 months and 23% turned at 2 years or older. Car seat packaging and clinicians were the most common information sources. Demographic characteristics associated with turning to face forward at or before 12 months of age in 2011 (parent age, education, household income, rural residence) were not significantly associated with transitioning at or before 12 months in 2013. Conclusions Delaying the transition to a forward-facing car seat still represents an opportunity to improve passenger safety in the U.S. As common sources of information, clinicians may be influential in a parent’s decision to turn their child’s car seat to face forward. PMID:25576520

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.

Effects of auditory cues on gait initiation and turning in patients with Parkinson's disease.

PubMed

Gómez-González, J; Martín-Casas, P; Cano-de-la-Cuerda, R

2016-12-08

To review the available scientific evidence about the effectiveness of auditory cues during gait initiation and turning in patients with Parkinson's disease. We conducted a literature search in the following databases: Brain, PubMed, Medline, CINAHL, Scopus, Science Direct, Web of Science, Cochrane Database of Systematic Reviews, Cochrane Library Plus, CENTRAL, Trip Database, PEDro, DARE, OTseeker, and Google Scholar. We included all studies published between 2007 and 2016 and evaluating the influence of auditory cues on independent gait initiation and turning in patients with Parkinson's disease. The methodological quality of the studies was assessed with the Jadad scale. We included 13 studies, all of which had a low methodological quality (Jadad scale score≤2). In these studies, high-intensity, high-frequency auditory cues had a positive impact on gait initiation and turning. More specifically, they 1) improved spatiotemporal and kinematic parameters; 2) decreased freezing, turning duration, and falls; and 3) increased gait initiation speed, muscle activation, and gait speed and cadence in patients with Parkinson's disease. We need studies of better methodological quality to establish the Parkinson's disease stage in which auditory cues are most beneficial, as well as to determine the most effective type and frequency of the auditory cue during gait initiation and turning in patients with Parkinson's disease. Copyright © 2016 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

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.

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

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.

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.

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

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…

Are U-Shaped Developmental Trajectories Illusory?

ERIC Educational Resources Information Center

Vouloumanos, Athena

2011-01-01

Without criteria for what counts as a U/N-shaped developmental trajectory, it is not clear how many legitimate "Us" really exist. Many, if not all, "Us" may turn out to be illusions borne out of our sampling methods, task construal, and blurry lenses of description. (Contains 2 figures.)

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

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.

Low-β magnetic reconnection driven by the intense lasers with a double-turn capacitor-coil

NASA Astrophysics Data System (ADS)

Yuan, Xiaoxia; Zhong, Jiayong; Zhang, Zhe; Zhou, Weimin; Teng, Jian; Li, Yutong; Han, Bo; Yuan, Dawei; Lin, Jun; Liu, Chang; Li, Yanfei; Zhu, Baojun; Wei, Huigang; Liang, Guiyun; Hong, Wei; He, Shukai; Yang, Siqian; Zhao, Yongqiang; Deng, Zhigang; Lu, Feng; Zhang, Zhimeng; Zhu, Bin; Zhou, Kainan; Su, Jingqin; Zhao, Zongqing; Gu, Yuqiu; Zhao, Gang; Zhang, Jie

2018-06-01

A double-turn capacitor-coil is used to produce a magnetic field (38.5 T) and construct a topology of magnetic reconnection in a low-β (β < 1) plasma environment. The device is constructed with two metallic U-turn coils connecting two parallel metallic disks. High energy lasers are employed to ablate one disk spontaneously driving two currents in the two coils, which produces an interactive magnetic field topology. We demonstrated through experiments and numerical simulations that the reconnection process takes place between two non-uniform magnetic fields created by the coils, and that the plasma state and the associated magnetic topology in the process can be seen via the technology of the optical probe beam and the proton backlight.

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.

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.

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

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.

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...

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...

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 ...

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.

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…

Solar U- and J- Bursts at the Frequencies 10-30MHz

NASA Astrophysics Data System (ADS)

Dorovskyy, V. V.; Melnik, V. N.; Konovalenko, A. A.; Abranin, E. P.; Rucker, H. O.; Lecacheux, A.

2006-08-01

In the present report we discuss the results of observations of solar U- and J- bursts over the frequency range 10-30MHz, which have been obtained within the framework of an international observational campaign in June - August, 2004 at the radio telescope UTR-2 (Kharkov, Ukraine). We succeed to observe these types of bursts for the first time at such a low frequencies due to combination of large effective area of the radio telescope and high sensitivity of the new back-end. During June - August, 2004 about 30 U- and J- bursts were registered, and only 5 of them were confidently identified as U-bursts that may speak about the relative sparsity of the latter at mentioned frequencies. Both the isolated bursts and their sequences were observed. On average the turning frequencies lay in the range 10-22 MHz that corresponds to the arches heliocentric heights of 1.6-2.2 solar radii. In some sequences the bursts turning frequency was stable that may indicate the arch stability, while in others the turning frequency had tendency to vary from burst to burst. Durations of U- and J- bursts did not differ from those of usual Type III bursts (3-7s), while the drift rates of an ascending arm (on the average -1MHz/ s) was a little bit lower, than those of ordinary Type III bursts in this range. The harmonic structure of U- and J- bursts, and also Jb-J pairs (analogous to IIIb-III pairs) were registered. Also L-shaped bursts (Leblanc and Hoyos, 1985) were recorded. A specific feature of L-shaped bursts is prolonged zero-drift region on their dynamic spectra. The sizes and configurations of the arches were estimated on the base of obtained data. Possible explanations of the observed properties of U- and J- bursts are discussed.

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

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.

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

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.

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

Nuclear Time Delay Effects on K-Vacancy Production in Deep-Inelastic U+U Collisions

NASA Astrophysics Data System (ADS)

Molitoris, John David

1987-09-01

- nent of fissioning nuclei ((TURN)50%) whose fission time (T(,f)) can not be much smaller than the U K-vacancy decay time (T(,K)(U) (DBLTURN) 10('-18) sec). The overall P(,K)('3-body) results and a study of distinct spatial orientations of the fission fragments in relation to the surviving U-like partner show a reduction in P(,K)('3-body) for TKEL >(, )175 MeV. This could imply that T(,f) (LESSTHEQ) 10('-18) sec for TKEL >(, )175 MeV. Measurement of the net U K x-ray yield over all TKEL in 4-body break-up reveals that P(,K)('4-body) = 0.36 (+OR-) 0.08. When compared to similar net probabilities for 2- and 3-body break-up, this indicates that about 50% of the U-like reaction partners which ultimately fission live at least 10('-18) sec. This result is in overall agreement with the 3-body results, but exceeds usual nuclear physics estimates of T(,f) (TURN) 10('-20) sec. However, crystal blocking techniques have observed long lived fission components (T(,f) (GREATERTHEQ) 10('-18) sec) in some nuclear reactions.

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.

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.

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.

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

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

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.

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.

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...

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...

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...

Timing performance of a self-cancelling turn-signal mechanism in motorcycles based on the ATMega328P microcontroller

NASA Astrophysics Data System (ADS)

Nurbuwat, Adzin Kondo; Eryandi, Kholid Yusuf; Estriyanto, Yuyun; Widiastuti, Indah; Pambudi, Nugroho Agung

2018-02-01

The objective of this study is to measure the time performance of a self-cancelling turn signal mechanism based on the In this study the performance of self-cancelling turn signal based on ATMega328P microcontroller is measured at low speed and high speed treatment on motorcycles commonly used in Indonesia. Time performance measurements were made by comparing the self-cancelling turn signal based on ATMega328P microcontroller with standard motor turn time. Measurements of time at low speed treatment were performed at a speed range of 15 km / h, 20 km / h, 25 km / h on the U-turn test trajectory. The angle of the turning angle of the potentiometer is determined at 3°. The limit of steering wheel turning angle at the potentiometer is set at 3°. For high-speed treatment is 30 km / h, 40 km / h, 50km / h, and 60 km / h, on the L-turn test track with a tilt angle (roll angle) read by the L3G4200D gyroscope sensor. Each speed test is repeated 3 replications. Standard time is a reference for self-cancelling turn signal performance. The standard time obtained is 15.68 s, 11.96 s, 9.34 s at low speed and 4.63 s, 4.06 s, 3.61 s, 3.13 s at high speed. The time test of self-cancelling turn signal shows 16.10 s, 12.42 s, 10.24 s at the low speed and 5.18, 4.51, 3.73, 3.21 at the high speed. At a speed of 15 km / h occurs the instability of motion turns motorcycle so that testing is more difficult. Small time deviations indicate the tool works well. The largest time deviation value is 0.9 seconds at low speed and 0.55 seconds at high speed. The conclusion at low velocity of the highest deviation value occurred at the speed of 25 km / h test due to the movement of slope with inclination has started to happen which resulted in slow reading of steering movement. At higher speeds the time slows down due to rapid sensor readings on the tilt when turning fast at ever higher speeds. The timing performance of self-cancelling turn signal decreases as the motorcycle turning

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

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.

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.

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

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.

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] ...

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] ...

[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.

The Application of 238U/235U as a Redox-Proxy for Past Ocean Chemistry

NASA Astrophysics Data System (ADS)

Andersen, M. B.; Westermann, S.; Bahniuk, A.; Vasconcelos, C.; McKenzie, J. A.; Föllmi, K. B.; Vance, D.

2014-12-01

The recent discovery of significant variation in 238U/235U caused by redox change at the surface Earth has led to its use to extract information on the oxygenation state of ancient oceans from marine sediments [e.g. 1]. Recent studies have focused on improving the understanding of the 238U/235U signature in modern marine carbonates [2] and black shales [3] to improve the robustness of this tracer. To further advance its use we have focused on improving our understanding of 238U/235U systematics in modern dolomite, another commonly occurring rock-type in the geological record, before turning to 238U/235U signatures in ancient sediments. The measured dolomite samples, precipitated in modern environments of coastal hypersaline lagoons in Brazil, all exhibit 238U/235U values that deviate from the seawater composition [3]. Observed values are both lighter (ca. 130 ppm; as also observed in dolomite from tidal-ponds on Bahamas [2]) and heavier (50-180 ppm). These distinct 238U/235U values for different dolomite-precipitates likely attest to the particular formation style, as well as early diagenetic processes. We use such modern settings to discuss the utility of 238U/235U in ancient sediments, the singularity of any observed 238U/235U signal, its relation to global ocean chemistry and potential diagenetic overprinting. These constraints are then used to evaluate a well-preserved marine carbonate section [4] and published black shale 238U/235U data [1], both deposited during the Oceanic Anoxic Event 2 (93 Ma). We discuss the capabilities of both the carbonate and black shale section for retaining information on the 238U/235U composition in the ocean during OAE 2. [1] Montoya-Pino et al. (2010) Geology, 38, 315-318 [2] Romaniello et al. (2013) 362, 305-316 [3] Andersen et al. (2014) EPSL, 400, 184-194 [4] Westermann et al. (2010) Cret. Res., 31, 500-514

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.

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.

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...

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

7. View into Building 802, front entry hall to "U" ...

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

7. View into Building 802, front entry hall to "U" turn. Light and shower spigot seen through chain-link fence, facing east. - Naval Air Station Fallon, 100-man Fallout Shelter, 800 Complex, off Carson Road near intersection of Pasture & Berney Roads, Fallon, Churchill County, NV

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.

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.

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

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

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

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.

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...

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.

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.

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.

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.

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

The place of punishment: Variation in the provision of inmate services staff across the punitive turn

PubMed Central

Phelps, Michelle S.

2013-01-01

Despite the growing literature on the punitive turn, knowledge of how the experience of American imprisonment varied across time and place remain limited. This article begins to fill that gap, providing a more nuanced portrayal of rehabilitation during the punitive turn. Purpose To examine how one aspect of the rehabilitative ideal in practice—the provision of staff dedicated to inmate services—varied across time and place over the past 30 years. Methods The article presents statistics on the inmate-to-staff ratios for inmate services staff (including teachers, counselors, doctors, etc.) between the years 1979 and 2005 for all 50 U.S. states. Results The analyses reveal that, while there was a substantial decline in the services staff ratio during the 1990s and 2000s, this shift across time paled in comparison to variation across place. Northeastern prison systems, for example, maintained higher inmate services staff ratios in 2005 than Southern states in any year. In addition, results suggest state variation is related to differences in prison crowding, inmates’ racial composition, and political cultures. Conclusions The findings suggest the punitive turn was more variegated and partial than is often assumed and highlight the importance of exploring state variation in penal practices. PMID:23794764

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.

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...

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...

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.

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

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.

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.

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.

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.

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.

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.

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.

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.

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.

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

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.

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.

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

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.

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.

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

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.

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…

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.

Foreign Aid: An Introduction to U.S. Programs and Policy

DTIC Science & Technology

2009-02-10

additionally meeting U.S. humanitarian objectives. Microcredit programs may help develop local economies while at the same time providing food and...training and expertise to fledgling microcredit institutions. In recent years, antiretroviral drugs (ARVs) provided through PEPFAR programs to...For instance, grants are sometimes provided to microcredit organizations which in turn provide loans to microentrepreneurs. Through the USAID-funded

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.

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 ...

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:…

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.

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.

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…

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…

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…

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…

Integrated tephrostratigraphy and stable isotope stratigraphy in the Japan Sea and East China Sea using IODP Sites U1426, U1427, and U1429, Expedition 346 Asian Monsoon

NASA Astrophysics Data System (ADS)

Sagawa, Takuya; Nagahashi, Yoshitaka; Satoguchi, Yasufumi; Holbourn, Ann; Itaki, Takuya; Gallagher, Stephen J.; Saavedra-Pellitero, Mariem; Ikehara, Ken; Irino, Tomohisa; Tada, Ryuji

2018-12-01

established at the shallower Site U1427 can be correlated to Site U1426, and in turn to all sites drilled during Expedition 346, based on correlations of dark-light layering.

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…

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.

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.

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…

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.

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

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...

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...

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...

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...

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...

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

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.

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

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.

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.

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.

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

Resonant tunneling through S- and U-shaped graphene nanoribbons.

PubMed

Zhang, Z Z; Wu, Z H; Chang, Kai; Peeters, F M

2009-10-14

We theoretically investigate resonant tunneling through S- and U-shaped nanostructured graphene nanoribbons. A rich structure of resonant tunneling peaks is found emanating from different quasi-bound states in the middle region. The tunneling current can be turned on and off by varying the Fermi energy. Tunability of resonant tunneling is realized by changing the width of the left and/or right leads and without the use of any external gates.

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.

Turning free speech into corporate speech: Philip Morris' efforts to influence U.S. and European journalists regarding the U.S. EPA report on secondhand smoke.

PubMed

Muggli, Monique E; Hurt, Richard D; Becker, Lee B

2004-09-01

Previously secret internal tobacco company documents show that the tobacco industry launched an extensive multifaceted effort to influence the scientific debate about the harmful effects of secondhand smoke. Integral to the industry's campaign was an effort to derail the Environmental Protection Agency's (EPA) risk assessment on environmental tobacco smoke (ETS) by recruiting a network of journalists to generate news articles supporting the industry's position and pushing its public relations messages regarding the ETS issue. Searches of previously secret internal tobacco industry records were conducted online and at the Minnesota Tobacco Document Depository. In addition, searches on the World Wide Web were conducted for each National Journalism Center alumnus. Lexis-Nexis was used to locate news stories written by the journalists cited in this paper. Philip Morris turned to its public relations firm Burson Marsteller to "build considerable reasonable doubt em leader particularly among consumers" about the "scientific weaknesses" of the EPA report. A Washington, DC, media and political consultant Richard Hines was a key player in carrying out Burson Marsteller's media recommendations of "EPA bashing" for Philip Morris. In March 1993, Philip Morris' vice president of corporate affairs policy and administration reported to Steve Parrish, vice president and general counsel of Philip Morris, that their consultant was "responsible for a number of articles that have appeared in em leader major news publications regarding EPA and ETS." In addition to placing favorable stories in the press through its consultant, Philip Morris sought to expand its journalist network by financially supporting a U.S. school of journalism; the National Journalism Center (NJC). Philip Morris gleaned "about 15 years worth of journalists at print and visual media throughout the country em leader to get across [its] side of the story" resulting in "numerous pieces consistent with our point of

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...

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.

[U.S. renewable fuel standard implementation mechanism and market tracking].

PubMed

Kang, Liping; Earley, Robert; An, Feng; Zhang, Yu

2013-03-01

U.S. Renewable Fuel Standard (RFS) is a mandatory policy for promoting the utilization of biofuels in road transpiration sector in order to reduce the country's dependency on foreign oil and greenhouse gas emissions. U.S. Environmental Protection Agency (EPA) defines the proportion of renewable fuels according to RFS annual target, and requests obligated parties such like fossil fuel refiner, blenders and importer in the U.S. to complete Renewable Volume Obligation (RVO) every year. Obligated parties prove they have achieved their RVO through a renewable fuels certification system, which generates Renewable Identification Numbers (RINs) for every gallon of qualified renewable fuels produced or imported into U.S., RINs is a key for tracking renewable fuel consumption, which in turn is a key for implementing the RFS in the U.S., separated RINs can be freely traded in market and obligated parties could fulfill their RVO through buying RINs from other stakeholders. This briefing paper highlights RFS policy implementing mechanism and marketing tracking, mainly describes importance of RINs, and the method for generating and tracking RINs by both government and fuels industry participants.

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.

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.

Emergence of a new S U (4 ) symmetry in the baryon spectrum

NASA Astrophysics Data System (ADS)

Denissenya, M.; Glozman, L. Ya.; Pak, M.

2015-10-01

Recently, a large degeneracy of J =1 mesons—that is, larger than the S U (2 )L×S U (2 )R×U (1 )A symmetry of the QCD Lagrangian—has been discovered upon truncation of the near-zero modes from the valence quark propagators. It has been found that this degeneracy represents the S U (4 ) group that includes the chiral rotations as well as the mixing of left- and right-handed quarks. This symmetry group turns out to be a symmetry of confinement in QCD. Consequently, one expects that the same symmetry should persist upon the near-zero mode removal in other hadron sectors as well. It has been shown that indeed the J =2 mesons follow the same symmetry pattern upon the low-lying mode elimination. Here we demonstrate the S U (4 ) symmetry of baryons once the near-zero modes are removed from the quark propagators. We also show a degeneracy of states belonging to different irreducible representations of S U (4 ). This implies a larger symmetry that includes S U (4 ) as a subgroup.

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

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

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

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.

Drugs in Afghanistan: The Challenges With Implementing U.S. Strategy

DTIC Science & Technology

2008-03-13

governance, allow Islamic extremists to turn a poisonous ideology into a global movement. —Robert M . Gates1 The U.S. National Security Strategy...detoxify the country of Afghanistan and sever its ties to the insurgency. Endnotes 1 Robert M . Gates, “Munich Conference on Security Policy...State, “Background Note: Afghanistan.” 8 Antonio Donini , Humanitarian Agenda 2015 Afghanistan Country Study, Briefing Paper (Medford, MA: Feinstein

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.

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.

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.

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)

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.

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.

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.

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.

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.

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

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.

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

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/.

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

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.

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.

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/

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.

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.

Russian Political, Economic, and Security Issues and U.S. Interests

DTIC Science & Technology

2008-08-26

concerns and on nuclear non-proliferation in general. Russia’s actions in Georgia, however, could be a turning point in U.S.-Russian relations...Russia’s actions also arouse anxiety in other Soviet successor states, especially those with large Russian minorities, such as Ukraine and Kazakhstan...transforming Yukos into a major global energy company. Khodorkovski criticized some of Putin’s actions , financed anti-Putin political parties, and hinted

Russian Political, Economic, and Security Issues and U.S. Interests

DTIC Science & Technology

2008-10-06

concerns and on nuclear non-proliferation in general. Russia’s actions in Georgia, however, could be a turning point in U.S.-Russian relations. Russia’s... actions also arouse anxiety in other Soviet successor states, especially those with large Russian minorities, such as Ukraine and Kazakhstan...into a major global energy company. Khodorkovski criticized some of Putin’s actions , financed anti-Putin political parties, and hinted that he might

U.S.-Brazil Security Cooperation and the State Partnership Program

DTIC Science & Technology

2015-06-01

the recognition they deserve, and the U.S. ultimately risks losing its influence.29 As the former Secretary of State, Hillary Clinton believed...remains strong. Therefore, as the political situation needs to be mended, one of the best and most logical ways for doing so is through security...demonstrate its political discontent by stagnating the agreements. The negative trend that began in 2013, however, is finally beginning to turn positive

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.

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…

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...

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...

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.

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

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

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.

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.

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…

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.

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 ...

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...

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

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)

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...

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.

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.

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

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.

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

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

[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.

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.

Deploying and sharing U-Compare workflows as web services.

PubMed

Kontonatsios, Georgios; Korkontzelos, Ioannis; Kolluru, Balakrishna; Thompson, Paul; Ananiadou, Sophia

2013-02-18

U-Compare is a text mining platform that allows the construction, evaluation and comparison of text mining workflows. U-Compare contains a large library of components that are tuned to the biomedical domain. Users can rapidly develop biomedical text mining workflows by mixing and matching U-Compare's components. Workflows developed using U-Compare can be exported and sent to other users who, in turn, can import and re-use them. However, the resulting workflows are standalone applications, i.e., software tools that run and are accessible only via a local machine, and that can only be run with the U-Compare platform. We address the above issues by extending U-Compare to convert standalone workflows into web services automatically, via a two-click process. The resulting web services can be registered on a central server and made publicly available. Alternatively, users can make web services available on their own servers, after installing the web application framework, which is part of the extension to U-Compare. We have performed a user-oriented evaluation of the proposed extension, by asking users who have tested the enhanced functionality of U-Compare to complete questionnaires that assess its functionality, reliability, usability, efficiency and maintainability. The results obtained reveal that the new functionality is well received by users. The web services produced by U-Compare are built on top of open standards, i.e., REST and SOAP protocols, and therefore, they are decoupled from the underlying platform. Exported workflows can be integrated with any application that supports these open standards. We demonstrate how the newly extended U-Compare enhances the cross-platform interoperability of workflows, by seamlessly importing a number of text mining workflow web services exported from U-Compare into Taverna, i.e., a generic scientific workflow construction platform.

Deploying and sharing U-Compare workflows as web services

PubMed Central

2013-01-01

Background U-Compare is a text mining platform that allows the construction, evaluation and comparison of text mining workflows. U-Compare contains a large library of components that are tuned to the biomedical domain. Users can rapidly develop biomedical text mining workflows by mixing and matching U-Compare’s components. Workflows developed using U-Compare can be exported and sent to other users who, in turn, can import and re-use them. However, the resulting workflows are standalone applications, i.e., software tools that run and are accessible only via a local machine, and that can only be run with the U-Compare platform. Results We address the above issues by extending U-Compare to convert standalone workflows into web services automatically, via a two-click process. The resulting web services can be registered on a central server and made publicly available. Alternatively, users can make web services available on their own servers, after installing the web application framework, which is part of the extension to U-Compare. We have performed a user-oriented evaluation of the proposed extension, by asking users who have tested the enhanced functionality of U-Compare to complete questionnaires that assess its functionality, reliability, usability, efficiency and maintainability. The results obtained reveal that the new functionality is well received by users. Conclusions The web services produced by U-Compare are built on top of open standards, i.e., REST and SOAP protocols, and therefore, they are decoupled from the underlying platform. Exported workflows can be integrated with any application that supports these open standards. We demonstrate how the newly extended U-Compare enhances the cross-platform interoperability of workflows, by seamlessly importing a number of text mining workflow web services exported from U-Compare into Taverna, i.e., a generic scientific workflow construction platform. PMID:23419017

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.

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…

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.

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

DTIC Science & Technology

1968-10-11

CHNAVVLAT (Code 04)(2) COMSEVENTFLT (Hist. Team ) Pres, NAVWARCOL .. ". COMPHIBLANT COMWHIBPAC COMCBPAC COMBLANT COI4NAVFACENGCOM U...ganda Team with a Australian Advisor, about 31 miles north of Vinh Lcng. PbR 87 landed the troops embarked and the Australian 0 Advisor, but when PBR...responded to the situation and apprehended one man who was turned over to the Vietnamese National Police, The Royal Australian diving team at Vung - Tau

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

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].

Aromatic residues engineered into the beta-turn nucleation site of ubiquitin lead to a complex folding landscape, non-native side-chain interactions, and kinetic traps.

PubMed

Rea, Anita M; Simpson, Emma R; Meldrum, Jill K; Williams, Huw E L; Searle, Mark S

2008-12-02

The fast folding of small proteins is likely to be the product of evolutionary pressures that balance the search for native-like contacts in the transition state with the minimum number of stable non-native interactions that could lead to partially folded states prone to aggregation and amyloid formation. We have investigated the effects of non-native interactions on the folding landscape of yeast ubiquitin by introducing aromatic substitutions into the beta-turn region of the N-terminal beta-hairpin, using both the native G-bulged type I turn sequence (TXTGK) as well as an engineered 2:2 XNGK type I' turn sequence. The N-terminal beta-hairpin is a recognized folding nucleation site in ubiquitin. The folding kinetics for wt-Ub (TLTGK) and the type I' turn mutant (TNGK) reveal only a weakly populated intermediate, however, substitution with X = Phe or Trp in either context results in a high propensity to form a stable compact intermediate where the initial U-->I collapse is visible as a distinct kinetic phase. The introduction of Trp into either of the two host turn sequences results in either complex multiphase kinetics with the possibility of parallel folding pathways, or formation of a highly compact I-state stabilized by non-native interactions that must unfold before refolding. Sequence substitutions with aromatic residues within a localized beta-turn capable of forming non-native hydrophobic contacts in both the native state and partially folded states has the undesirable consequence that folding is frustrated by the formation of stable compact intermediates that evolutionary pressures at the sequence level may have largely eliminated.

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.

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.

The <u>Be>rkeley <u>A>tmospheric <u>C>O2 <u>O>bservation <u>N>etwork (BEACON): Measuring Greenhouse Gases and Criteria Pollutants within the Urban Dome

NASA Astrophysics Data System (ADS)

Teige, V. E.; Weichsel, K.; Hooker, A.; Wooldridge, P. J.; Cohen, R. C.

2012-12-01

Efforts to curb greenhouse gas emissions, while global in their impacts, often focus on local and regional scales for execution and are dependent on the actions of communities and individuals. Evaluating the effectiveness of local policies requires observations with much higher spatial resolution than are currently available---kilometer scale. The <u>Be>rkeley <u>A>tmospheric <u>C>O2 <u>O>bservation <u>N>etwork (BEACON):, launched at the end of 2011, aims to provide measurements of urban-scale concentrations of CO2, temperature, pressure, relative humidity, O3, CO, and NO2 with sufficient spatial and temporal resolution to characterize the sources of CO2 within cities. Our initial deployment in Oakland, California uses ~40 sensor packages at a roughly 2 km spacing throughout the city. We will present an initial analysis of the vertical gradients and other spatial patterns observed to date.

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.

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

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

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,…

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…

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.

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.

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.

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.

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.

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…

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.

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.

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,…

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

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.

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.

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…

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

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

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.

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...

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.

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

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

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.

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 ...

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.

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

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/.

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.}

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...

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. ...

"The Undesirability of Admitting Deaf Mutes": U.S. Immigration Policy and Deaf Immigrants, 1882-1924

ERIC Educational Resources Information Center

Baynton, Douglas C.

2006-01-01

When the federal government began in the 1880s to regulate immigration, the exclusion of what were termed "defectives" was one of the primary aims. Deaf people were among the thousands of disabled immigrants turned back each year at U.S. ports as "undesirables." Stereotyped as economically dependent and as carriers of potentially defective genes,…

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.

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.

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

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.

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

Poly(acrylic acid)-templated silver nanoclusters as a platform for dual fluorometric turn-on and colorimetric detection of mercury (II) ions.

PubMed

Tao, Yu; Lin, Youhui; Huang, Zhenzhen; Ren, Jinsong; Qu, Xiaogang

2012-01-15

An easy prepared fluorescence turn-on and colorimetric dual channel probe was developed for rapid assay of Hg(2+) ions with high sensitivity and selectivity by using poly(acrylic acid)-templated silver nanoclusters (PAA-AgNCs). The PAA-AgNCs exhibited weak fluorescence, while upon the addition of Hg(2+) ions, AgNCs gives a dramatic increase in fluorescence as a result of the changes of the AgNCs states. The detection limit was estimated to be 2 nM, which is much lower than the Hg(2+) detection requirement for drinking water of U.S. Environmental Protection Agency, and the turn-on sensing mode offers additional advantage to efficiently reduce background noise. Also, a colorimetric assay of Hg(2+) ions can be realized due to the observed absorbance changes of the AgNCs. More importantly, the method was successfully applied to the determination of Hg(2+) ions in real water samples, which suggests our proposed method has a great potential of application in environmental monitoring. Copyright © 2011 Elsevier B.V. All rights reserved.

Phase Retrieval System for Assessing Diamond Turning and Optical Surface Defects

NASA Technical Reports Server (NTRS)

Dean, Bruce; Maldonado, Alex; Bolcar, Matthew

2011-01-01

An optical design is presented for a measurement system used to assess the impact of surface errors originating from diamond turning artifacts. Diamond turning artifacts are common by-products of optical surface shaping using the diamond turning process (a diamond-tipped cutting tool used in a lathe configuration). Assessing and evaluating the errors imparted by diamond turning (including other surface errors attributed to optical manufacturing techniques) can be problematic and generally requires the use of an optical interferometer. Commercial interferometers can be expensive when compared to the simple optical setup developed here, which is used in combination with an image-based sensing technique (phase retrieval). Phase retrieval is a general term used in optics to describe the estimation of optical imperfections or aberrations. This turnkey system uses only image-based data and has minimal hardware requirements. The system is straightforward to set up, easy to align, and can provide nanometer accuracy on the measurement of optical surface defects.

Mass enhances speed but diminishes turn capacity in terrestrial pursuit predators.

PubMed

Wilson, Rory P; Griffiths, Iwan W; Mills, Michael G L; Carbone, Chris; Wilson, John W; Scantlebury, David M

2015-08-07

The dynamics of predator-prey pursuit appears complex, making the development of a framework explaining predator and prey strategies problematic. We develop a model for terrestrial, cursorial predators to examine how animal mass modulates predator and prey trajectories and affects best strategies for both parties. We incorporated the maximum speed-mass relationship with an explanation of why larger animals should have greater turn radii; the forces needed to turn scale linearly with mass whereas the maximum forces an animal can exert scale to a 2/3 power law. This clarifies why in a meta-analysis, we found a preponderance of predator/prey mass ratios that minimized the turn radii of predators compared to their prey. It also explained why acceleration data from wild cheetahs pursuing different prey showed different cornering behaviour with prey type. The outcome of predator prey pursuits thus depends critically on mass effects and the ability of animals to time turns precisely.

Optimization of the multi-turn injection efficiency for a medical synchrotron

NASA Astrophysics Data System (ADS)

Kim, J.; Yoon, M.; Yim, H.

2016-09-01

We present a method for optimizing the multi-turn injection efficiency for a medical synchrotron. We show that for a given injection energy, the injection efficiency can be greatly enhanced by choosing transverse tunes appropriately and by optimizing the injection bump and the number of turns required for beam injection. We verify our study by applying the method to the Korea Heavy Ion Medical Accelerator (KHIMA) synchrotron which is currently being built at the campus of Dongnam Institute of Radiological and Medical Sciences (DIRAMS) in Busan, Korea. First the frequency map analysis was performed with the help of the ELEGANT and the ACCSIM codes. The tunes that yielded good injection efficiency were then selected. With these tunes, the injection bump and the number of turns required for injection were then optimized by tracking a number of particles for up to one thousand turns after injection, beyond which no further beam loss occurred. Results for the optimization of the injection efficiency for proton ions are presented.

78 FR 36412 - Notice of Policy Clarification for the Registration of Aircraft to U.S. Citizen Trustees in...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-18

... involving non-U.S. citizen trustors and beneficiaries. DATES: Effective Date: The policy described herein is effective September 16, 2013. FOR FURTHER INFORMATION CONTACT: Joseph Standell at 405-954-3296, Office of... problems in obtaining such information in turn affected the FAA's ability to conduct fully effective...

Impact Upon U.S. Security of a South African Nuclear Weapons Capability.

DTIC Science & Technology

1981-04-01

Simon Brand, dubbed the international companies as the " engine of growth" for the South African economy. The petroleum market, automobile industry , and...thereby halting the flow of metals key to high technology industries which in turn, are critical to U.S. national security. Should Washington’s...to produce nuclear weapons." * More specifically, we found that South Africa has: A sufficient scientific and industrial base on which to conduct

SLIM: A Big Turn for Ion Separation

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

Smith, Dick; Ibrahim, Yehia

Researchers at PNNL have drastically increased the speed and separation of ions by tackling one problem: turning ions around a corner. Their technology, Structures for Lossless Ion Manipulations, or SLIM, could take the form of new instruments for doctors and other applications.

When attempts at robbing prey turn fatal

NASA Astrophysics Data System (ADS)

Dejean, Alain; Corbara, Bruno; Azémar, Frédéric; Carpenter, James M.

2012-07-01

Because group-hunting arboreal ants spread-eagle insect prey for a long time before retrieving them, these prey can be coveted by predatory flying insects. Yet, attempting to rob these prey is risky if the ant species is also an effective predator. Here, we show that trying to rob prey from Azteca andreae workers is a fatal error as 268 out of 276 potential cleptobionts (97.1 %) were captured in turn. The ant workers hunt in a group and use the "Velcro®" principle to cling firmly to the leaves of their host tree, permitting them to capture very large prey. Exceptions were one social wasp, plus some Trigona spp. workers and flies that landed directly on the prey and were able to take off immediately when attacked. We conclude that in this situation, previously captured prey attract potential cleptobionts that are captured in turn in most of the cases.

The Lewisian turning point and international migration: the case of Japan.

PubMed

Watanabe, S

1994-01-01

"This article critically examines the Lewisian turning point [concerning the availability of unlimited manpower resources] in light of Japan's experience since the mid-1800s. Japan reached its Lewisian turning point around 1960. Contrary to the assumptions of the theory however, the findings for Japan indicate that political factors have been more determinative of the rate of migration than purely economic ones. Prior to its turning point in 1960, international relations, war and forced repatriation were the decisive factors. Recently, though the inflow of foreign workers to fill labor shortages has increased, so also has the outflow of Japanese to accompany direct foreign investment." excerpt

Insourcing and Outsourcing for U.S. Department of Defense IT Projects: A Model

DTIC Science & Technology

2011-01-01

positioning or reduced force readiness. This paper provides an introduction to the insourcing and outsourcing dilemma in today’s fiscally challenged ...force readiness. This paper provides an introduction to the insourcing and outsourcing dilemma in today?s fiscally challenged environment. It discusses...could risk loss to its global competitive posture, which in turn could impact the ability of the U.S. to defend itself by hampering national security

Possibilities in the Boy Turn? Comparative Lessons from Australia and Iceland

ERIC Educational Resources Information Center

Johannesson, Ingolfur Asgeir; Lingard, Bob; Mills, Martin

2009-01-01

Recognising that there is now a globalised educational discourse about "failing boys" circulating in the privileged nations of the global north, this article provides a comparative perspective on educational policy responses to the "boy turn" in Australia and Iceland. Specificities of the responses to the boy turn in the two…

TURNING POINTS IN THE LIVES OF LESBIAN AND GAY ADULTS AGE 50 AND OVER

PubMed Central

Fredriksen-Goldsen, Karen I.

2016-01-01

Little is known about how lesbians and gay men perceive the turning points that define their life trajectories. This study uses qualitative interview data to understand which experiences lesbian women and gay men age 50 and older identify as turning points and explore gender differences. In depth, face-to-face qualitative interviews were conducted with a subset of participants (n=33) from the Caring and Aging with Pride survey. The most common turning points identified were relationship and occupation related. Lesbians more frequently identified the break-up of a relationship and occupational and educational related experiences as turning points. Gay men more commonly indicated that the beginning of a relationship and HIV/AIDS related experiences were turning points. The turning points were analyzed according to principles of the life course theory and narrative analysis. PMID:28066158

Description of the heterotic string solutions in U(N) supersymmetric QCD

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

Bolokhov, P. A.; Theoretical Physics Department, St. Petersburg State University, Ulyanovskaya 1, Peterhof, St. Petersburg, 198504; Shifman, M.

2009-04-15

We continue the study of heterotic non-Abelian Bogomol'nyi-Prasad-Sommerfield-saturated flux tubes (strings). Previously, such solutions were obtained [M. Shifman and A. Yung, Phys. Rev. D 77, 125016 (2008).] in a particular U(2) gauge theory: N=2 supersymmetric QCD deformed by superpotential terms of a special type breaking N=2 supersymmetry down to N=1. Here we generalize the previous results to U(N) gauge theories. As was suggested by Edalati and Tong [M. Edalati and D. Tong, J. High Energy Phys. 05 (2007) 005.], the string world-sheet theory is a heterotic N=(0,2) sigma model, with the CP(N-1) target space for bosonic fields and an extramore » right-handed fermion which couples to the fermion fields of the N=(2,2) CP(N-1) model. We derive the heterotic N=(0,2) world-sheet model directly from the U(N) bulk theory. Parameters of the bulk theory are related to those of the world-sheet theory. Qualitatively this relation turns out to be the same as in the U(2) case.« less

Negotiating behavioural change: therapists' proposal turns in Cognitive Behavioural Therapy.

PubMed

Ekberg, Katie; Lecouteur, Amanda

2012-01-01

Cognitive behavioural therapy (CBT) is an internationally recognised method for treating depression. However, many of the techniques involved in CBT are accomplished within the therapy interaction in diverse ways, and with varying consequences for the trajectory of therapy session. This paper uses conversation analysis to examine some standard ways in which therapists propose suggestions for behavioural change to clients attending CBT sessions for depression in Australia. Therapists' proposal turns displayed their subordinate epistemic authority over the matter at hand, and emphasised a high degree of optionality on behalf of the client in accepting their suggestions. This practice was routinely accomplished via three standard proposal turns: (1) hedged recommendations; (2) interrogatives; and (3) information-giving. These proposal turns will be examined in relation to the negotiation of behavioural change, and the implications for CBT interactions between therapist and client will be discussed.

A Logical OR Redundancy within the Asx-Pro-Asx-Gly Type 1 {Beta}-Turn Motif

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

Lee, Jihun; Dubey, Vikash Kumar; Longo, Lian M.

2008-04-19

Turn secondary structure is essential to the formation of globular protein architecture. Turn structures are, however, much more complex than either {alpha}-helix or {beta}-sheet, and the thermodynamics and folding kinetics are poorly understood. Type I {beta}-turns are the most common type of reverse turn, and they exhibit a statistical consensus sequence of Asx-Pro-Asx-Gly (where Asx is Asp or Asn). A comprehensive series of individual and combined Asx mutations has been constructed within three separate type I 3:5 G1 bulge {beta}-turns in human fibroblast growth factor-1, and their effects on structure, stability, and folding have been determined. The results show amore » fundamental logical OR relationship between the Asx residues in the motif, involving H-bond interactions with main-chain amides within the turn. These interactions can be modulated by additional interactions with residues adjacent to the turn at positions i + 4 and i + 6. The results show that the Asx residues in the turn motif make a substantial contribution to the overall stability of the protein, and the Asx logical OR relationship defines a redundant system that can compensate for deleterious point mutations. The results also show that the stability of the turn is unlikely to be the prime determinant of formation of turn structure in the folding transition state.« less

Bodies with noncircular cross sections and bank-to-turn missiles

NASA Technical Reports Server (NTRS)

Jackson, C. M., Jr.; Sawyer, W. C.

1992-01-01

A development status evaluation is presented for the aerodynamics of missile configurations with noncircular cross-sections and bank-to-turn maneuvering systems, giving attention to cases with elliptical and square cross-sections, as well as bodies with variable cross-sections. The assessment of bank-to-turn missile performance notes inherent stability/control problems. A summary and index are provided for aerodynamic data on monoplanar configurations, including those which incorporate airbreathing propulsion systems.

Turning Down the Noise in the Blogosphere

DTIC Science & Technology

2009-05-01

Turning Down the Noise in the Blogosphere Khalid El-Arini, Gaurav Veda , Dafna Shahaf, Carlos Guestrin May 2009 CMU-ML-09-103 Report Documentation...Arini Gaurav Veda Dafna Shahaf Carlos Guestrin May 2009 CMU-ML-09-103 School of Computer Science Carnegie Mellon University Pittsburgh, PA 15213

Effect of policies on pellet production and forests in the U.S. South: a technical document supporting the Forest Service update of the 2010 RPA Assessment

Treesearch

Karen L. Abt; Robert C. Abt; Christopher S. Galik; Kenneth E. Skog

2014-01-01

Current policies in the European Union (EU) requiring renewable and low greenhouse gas-emitting energy are affecting wood products manufacturing and forests in the United States. These policies have led to increased U.S. pellet production and export to the EU, which has in turn affected U.S. forests and other wood products manufacturing. At this time, the primary...

Free energy determinants of secondary structure formation: III. beta-turns and their role in protein folding.

PubMed

Yang, A S; Hitz, B; Honig, B

1996-06-21

The stability of beta-turns is calculated as a function of sequence and turn type with a Monte Carlo sampling technique. The conformational energy of four internal hydrogen-bonded turn types, I, I', II and II', is obtained by evaluating their gas phase energy with the CHARMM force field and accounting for solvation effects with the Finite Difference Poisson-Boltzmann (FDPB) method. All four turn types are found to be less stable than the coil state, independent of the sequence in the turn. The free-energy penalties associated with turn formation vary between 1.6 kcal/mol and 7.7 kcal/mol, depending on the sequence and turn type. Differences in turn stability arise mainly from intraresidue interactions within the two central residues of the turn. For each combination of the two central residues, except for -Gly-Gly-, the most stable beta-turn type is always found to occur most commonly in native proteins. The fact that a model based on local interactions accounts for the observed preference of specific sequences suggests that long-range tertiary interactions tend to play a secondary role in determining turn conformation. In contrast, for beta-hairpins, long-range interactions appear to dominate. Specifically, due to the right-handed twist of beta-strands, type I' turns for -Gly-Gly- are found to occur with high frequency, even when local energetics would dictate otherwise. The fact that any combination of two residues is found able to adopt a relatively low-energy turn structure explains why the amino acid sequence in turns is highly variable. The calculated free-energy cost of turn formation, when combined with related numbers obtained for alpha-helices and beta-sheets, suggests a model for the initiation of protein folding based on metastable fragments of secondary structure.

The Turn-on of LCLS: the X-Ray Free Electron Laser at SLAC ( Keynote - 2011 JGI User Meeting)

ScienceCinema

Drell, Persis [SLAC National Accelerator Lab., Menlo Park, CA (United States)

2018-06-15

The U.S. Department of Energy Joint Genome Institute (JGI) invited scientists interested in the application of genomics to bioenergy and environmental issues, as well as all current and prospective users and collaborators, to attend the annual DOE JGI Genomics of Energy & Environment Meeting held March 22-24, 2011 in Walnut Creek, Calif. The emphasis of this meeting was on the genomics of renewable energy strategies, carbon cycling, environmental gene discovery, and engineering of fuel-producing organisms. The meeting features presentations by leading scientists advancing these topics. SLAC National Laboratory Director Persis Drell gives a keynote talk on "The Turn-on of LCLS: the X-Ray Free-Electron Laser at SLAC" at the 6th Genomics of Energy & Environment Meeting on March 22, 2011

Solid-state turn coordinator display

NASA Technical Reports Server (NTRS)

Meredith, B. D.; Crouch, R. K.; Kelly, W. L., IV

1975-01-01

A solid state turn coordinator display which employs light emitting diodes (LED's) as the display medium was developed to demonstrate the feasibility of such displays for aircraft applications. The input to the display is supplied by a fluidic inertial rate sensor used in an aircraft wing leveler system. The display is composed of the LED radial display face and the electronics necessary to address and drive the individual lines of LED's. Three levels of brightness are provided to compensate for the different amounts of ambient light present in the cockpit.

Twists and turns in the body: an imaging spectrum.

PubMed

Luk, Shiobhon Y; Fung, K H

2010-10-01

Life is full of twists and turns. These surprises can sometimes be wonderfully invigorating. Twists and turns can also occur in the body, however, sometimes with dangerous consequences. Torsion and volvulus are important causes of acute abdominal pain. The clinical symptoms and signs associated with torsion and volvulus are often non-specific and are difficult to diagnose clinically. Clinicians frequently rely on imaging methods to make the diagnosis. Prompt and accurate diagnosis is important to avoid the life-threatening complications of torsion and volvulus. Therefore, it is helpful to be familiar with the features of torsion and volvulus.

Abolishment of Spontaneous Flight Turns in Visually Responsive Drosophila.

PubMed

Ferris, Bennett Drew; Green, Jonathan; Maimon, Gaby

2018-01-22

Animals react rapidly to external stimuli, such as an approaching predator, but in other circumstances, they seem to act spontaneously, without any obvious external trigger. How do the neural processes mediating the execution of reflexive and spontaneous actions differ? We studied this question in tethered, flying Drosophila. We found that silencing a large but genetically defined set of non-motor neurons virtually eliminates spontaneous flight turns while preserving the tethered flies' ability to perform two types of visually evoked turns, demonstrating that, at least in flies, these two modes of action are almost completely dissociable. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of magneto rheological damper on tool vibration during hard turning

NASA Astrophysics Data System (ADS)

Paul, P. Sam; Varadarajan, A. S.

2012-12-01

Recently, the concept of hard turning has gained considerable attention in metal cutting as it can apparently replace the traditional process cycle of turning, heat treating, and finish grinding for assembly of hard wear resistant steel parts. The present investigation aims at developing a magneto rheological (MR) fluid damper for suppressing tool vibration and promoting better cutting performance during hard turning. The magneto rheological Fluid acts as a viscoelastic spring with non-linear vibration characteristics that are controlled by the composition of the magneto rheological fluid, the shape of the plunger and the electric parameters of the magnetizing field. Cutting experiments were conducted to arrive at a set of electrical, compositional and shape parameters that can suppress tool vibration and promote better cutting performance during turning of AISI 4340 steel of 46 HRC with minimal fluid application using hard metal insert with sculptured rake face. It was observed that the use of MR fluid damper reduces tool vibration and improves the cutting performance effectively. Also commercialization of this idea holds promise to the metal cutting industry.

Mass enhances speed but diminishes turn capacity in terrestrial pursuit predators

PubMed Central

Wilson, Rory P; Griffiths, Iwan W; Mills, Michael GL; Carbone, Chris; Wilson, John W; Scantlebury, David M

2015-01-01

The dynamics of predator-prey pursuit appears complex, making the development of a framework explaining predator and prey strategies problematic. We develop a model for terrestrial, cursorial predators to examine how animal mass modulates predator and prey trajectories and affects best strategies for both parties. We incorporated the maximum speed-mass relationship with an explanation of why larger animals should have greater turn radii; the forces needed to turn scale linearly with mass whereas the maximum forces an animal can exert scale to a 2/3 power law. This clarifies why in a meta-analysis, we found a preponderance of predator/prey mass ratios that minimized the turn radii of predators compared to their prey. It also explained why acceleration data from wild cheetahs pursuing different prey showed different cornering behaviour with prey type. The outcome of predator prey pursuits thus depends critically on mass effects and the ability of animals to time turns precisely. DOI: http://dx.doi.org/10.7554/eLife.06487.001 PMID:26252515

Determining the end of a musical turn: Effects of tonal cues.

PubMed

Hadley, Lauren V; Sturt, Patrick; Moran, Nikki; Pickering, Martin J

2018-01-01

Successful duetting requires that musicians coordinate their performance with their partners. In the case of turn-taking in improvised performance they need to be able to predict their partner's turn-end in order to accurately time their own entries. Here we investigate the cues used for accurate turn-end prediction in musical improvisations, focusing on the role of tonal structure. In a response-time task, participants more accurately determined the endings of (tonal) jazz than (non-tonal) free improvisation turns. Moreover, for the jazz improvisations, removing low frequency information (<2100Hz) - and hence obscuring the pitch relationships conveying tonality - reduced response accuracy, but removing high frequency information (>2100Hz) had no effect. Neither form of filtering affected response accuracy in the free improvisation condition. We therefore argue that tonal cues aided prediction accuracy for the jazz improvisations compared to the free improvisations. We compare our results with those from related speech research (De Ruiter et al., 2006), to draw comparisons between the structural function of tonality and linguistic syntax. Copyright © 2017. Published by Elsevier B.V.

Design and Analysis of Discrete Lateral Autopilots for Coordinated Bank- to-Turn Missiles

DTIC Science & Technology

1985-12-01

ANALYSIS OF DISCRETE LATERAL AUTOPILOTS FOR COORDINATED BANK-TO-TURN MISSILES * by Christos 1. Karadimas C)__ December 1935 LAJ *Thesis Advisor: Daniel .J...Include Security Clastfication) DESIGN AND ANALYSIS OF DISCRETE LATERAL AUTOPILOTS FOR .- COORDINATED BANK-TO-TURN MISSILES A - H . R o KARADIMAS ...Coordinated Bank-to-Turn Missiles - by Christos I. Karadimas Lieutenant, Hellenic Navy B.S., Hellenic Naval Academy, 1976 Submitted in partial

Timing in turn-taking and its implications for processing models of language

PubMed Central

Levinson, Stephen C.; Torreira, Francisco

2015-01-01

The core niche for language use is in verbal interaction, involving the rapid exchange of turns at talking. This paper reviews the extensive literature about this system, adding new statistical analyses of behavioral data where they have been missing, demonstrating that turn-taking has the systematic properties originally noted by Sacks et al. (1974; hereafter SSJ). This system poses some significant puzzles for current theories of language processing: the gaps between turns are short (of the order of 200 ms), but the latencies involved in language production are much longer (over 600 ms). This seems to imply that participants in conversation must predict (or ‘project’ as SSJ have it) the end of the current speaker’s turn in order to prepare their response in advance. This in turn implies some overlap between production and comprehension despite their use of common processing resources. Collecting together what is known behaviorally and experimentally about the system, the space for systematic explanations of language processing for conversation can be significantly narrowed, and we sketch some first model of the mental processes involved for the participant preparing to speak next. PMID:26124727

Kinematic and kinetic analysis of the fouetté turn in classical ballet.

PubMed

Imura, Akiko; Iino, Yoichi; Kojima, Takeji

2010-11-01

The fouetté turn in classical ballet dancing is a continuous turn with the whipping of the gesture leg and the arms and the bending and stretching of the supporting leg. The knowledge of the movement intensities of both legs for the turn would be favorable for the conditioning of the dancer's body. The purpose of this study was to estimate the intensities. The hypothesis of this study was that the intensities were higher in the supporting leg than in the gesture leg. The joint torques of both legs were determined in the turns performed by seven experienced female classical ballet dancers with inverse dynamics using three high-speed cine cameras and a force platform. The hip abductor torque, knee extensor and plantar flexor torques of the supporting leg were estimated to be exerted up to their maximum levels and the peaks of the torques were larger than the peaks of their matching torques of the gesture leg. Thus, the hypothesis was partly supported. Training of the supporting leg rather than the gesture leg would help ballet dancers perform many revolutions of the fouetté turn continuously.

Speech Cases Turned Aside by High Court

ERIC Educational Resources Information Center

Walsh, Mark

2012-01-01

The U.S. Supreme Court declined without comment to take up two major appeals involving student free-speech rights on the Internet. One appeal encompassed two cases decided in favor of students last June by the full U.S. Court of Appeals for the 3rd Circuit, in Philadelphia. The other appeal stemmed from a decision by the U.S. Court of Appeals for…

Static voltage distribution between turns of secondary winding of air-core spiral strip transformer and its application

NASA Astrophysics Data System (ADS)

Zhang, Hong-bo; Liu, Jin-liang; Cheng, Xin-bing; Zhang, Yu

2011-09-01

The static voltage distribution between winding turns has great impact on output characteristics and lifetime of the air-core spiral strip pulse transformer (ACSSPT). In this paper, winding inductance was calculated by electromagnetic theory, so that the static voltage distribution between turns of secondary winding of ACSSPT was analyzed conveniently. According to theoretical analysis, a voltage gradient because of the turn-to-turn capacitance was clearly noticeable across the ground turns. Simulation results of Pspice and CST EM Studio codes showed that the voltage distribution between turns of secondary winding had linear increments from the output turn to the ground turn. In experiment, the difference in increased voltage between the ground turns and the output turns of a 20-turns secondary winding is almost 50%, which is believed to be responsible for premature breakdown of the insulation, particularly between the ground turns. The experimental results demonstrated the theoretical analysis and simulation results, which had important value for stable and long lifetime ACSSPT design. A new ACSSPT with improved structure has been used successfully in intense electron beam accelerators steadily.

Reactivity of Ala-Gly dipeptide with β-turn secondary structure

NASA Astrophysics Data System (ADS)

Yu, Craig P.; Gerlei, Klára Z.; Rágyanszki, Anita; Jensen, Svend J. Knak; Viskolcz, Béla; Csizmadia, Imre G.

2018-01-01

The conformational space of β-turns of Ala-Gly dipeptide is analyzed theoretically using quantum mechanical methods. A number of potential minima are obtained and characterized. The potential energy surface suggests that β-turn conformers are susceptible to rapid radical formation, which leads to potential L and D epimerization. The calculated thermodynamics show that the radical mediated epimerization is possible and that the estimated barrier height for hydrogen abstraction on the Cα is the lowest for the Gly residue.

The K-turn motif in riboswitches and other RNA species☆

PubMed Central

Lilley, David M.J.

2014-01-01

The kink turn is a widespread structure motif that introduces a tight bend into the axis of duplex RNA. This generally functions to mediate tertiary interactions, and to serve as a specific protein binding site. K-turns or closely related structures are found in at least seven different riboswitch structures, where they function as key architectural elements that help generate the ligand binding pocket. This article is part of a Special Issue entitled: Riboswitches. PMID:24798078

Simulated visual field loss does not alter turning coordination in healthy young adults.

PubMed

Murray, Nicholas G; Ponce de Leon, Marlina; Ambati, V N Pradeep; Saucedo, Fabricio; Kennedy, Evan; Reed-Jones, Rebecca J

2014-01-01

Turning, while walking, is an important component of adaptive locomotion. Current hypotheses regarding the motor control of body segment coordination during turning suggest heavy influence of visual information. The authors aimed to examine whether visual field impairment (central loss or peripheral loss) affects body segment coordination during walking turns in healthy young adults. No significant differences in the onset time of segments or intersegment coordination were observed because of visual field occlusion. These results suggest that healthy young adults can use visual information obtained from central and peripheral visual fields interchangeably, pointing to flexibility of visuomotor control in healthy young adults. Further study in populations with chronic visual impairment and those with turning difficulties are warranted.

Experimental investigation of residual stress distribution during turning of weak stiffness revolving parts

NASA Astrophysics Data System (ADS)

Jiao, Sicheng; Zhang, Chengyan; Liu, Guancheng; Lu, Jiping; Tang, Shuiyuan

2017-08-01

A series of turning experiments have been carried out to study the effect of different cutting speed, feed rate and pre-tightening torque on residual stress distribution during turning of weak stiffness revolving parts. Surface residual stress and the peak residual compressive stress are selected from the typical residual stress distribution profile. The residual stress by turning was measured by X-ray diffraction method. In order to get the distribution of residual stress along depth direction, the specimens need to be etched layer by layer. From this investigation, it can be concluded that it is practicable to control the distribution of residual stress by changing the pre-tightening torque and cutting parameters during turning of weak stiffness revolving parts.

You cannot speak and listen at the same time: a probabilistic model of turn-taking.

PubMed

Donnarumma, Francesco; Dindo, Haris; Iodice, Pierpaolo; Pezzulo, Giovanni

2017-04-01

Turn-taking is a preverbal skill whose mastering constitutes an important precondition for many social interactions and joint actions. However, the cognitive mechanisms supporting turn-taking abilities are still poorly understood. Here, we propose a computational analysis of turn-taking in terms of two general mechanisms supporting joint actions: action prediction (e.g., recognizing the interlocutor's message and predicting the end of turn) and signaling (e.g., modifying one's own speech to make it more predictable and discriminable). We test the hypothesis that in a simulated conversational scenario dyads using these two mechanisms can recognize the utterances of their co-actors faster, which in turn permits them to give and take turns more efficiently. Furthermore, we discuss how turn-taking dynamics depend on the fact that agents cannot simultaneously use their internal models for both action (or messages) prediction and production, as these have different requirements-or, in other words, they cannot speak and listen at the same time with the same level of accuracy. Our results provide a computational-level characterization of turn-taking in terms of cognitive mechanisms of action prediction and signaling that are shared across various interaction and joint action domains.

Role of different β-turns in β-hairpin conformation and stability studied by optical spectroscopy.

PubMed

Wu, Ling; McElheny, Dan; Setnicka, Vladimír; Hilario, Jovencio; Keiderling, Timothy A

2012-01-01

Model β-hairpin peptides based on variations in the turn sequence of Cochran's tryptophan zipper peptide, SWTWENGKWTWK, were studied using electronic circular dichroism (ECD), fluorescence, and infrared (IR) spectroscopies. The trpzip2 Asn-Gly turn sequence was substituted with Thr-Gly, Aib-Gly, (D)Pro-Gly, and Gly-Asn (trpzip1) to study the impact of turn stability on β-hairpin formation. Stability and conformational changes of these hairpins were monitored by thermodynamic analyses of the temperature variation of both FTIR (amide I') and ECD spectral intensities. These changes were fit to a two-state model which yielded different T(m) values, representing the folding/unfolding process, for hairpins with different β-turns. Different β-turns show systematic contributions to hairpin structure formation, and their inclusion in hairpin design can modify the folding pathways. Aib-Gly or (D)Pro-Gly sequences stabilize the turn resulting in residual Trp-Trp interaction at high temperatures, but at the same time the β-structure (cross strand H-bonds) can become less stable due to constraints of the turn, as seen for (D)Pro-Gly. The structure of the Aib-Gly turn containing hairpin was determined by NMR and was shown to be like trpzip2 (Asn-Gly turn) as regards turn and strand geometries, but to differ from trpzip1 (Gly-Asn turn). The Munoz and Eaton statistical mechanically derived multistate model, tested as an alternate point of view, represented contributions from H-bonds and hydrophobic interactions as well as conformational change as interdependent. Use of different spectral methods that vary in dependence on these physical interactions along with the structural variations provided insight to the complex folding pathways of these small, well-folded peptides. Copyright © 2011 Wiley Periodicals, Inc.

The effect of right-turn-on-red on pedestrian and bicyclist accidents

DOT National Transportation Integrated Search

1981-10-01

Right-Turn-On-Red (RTOR) in its "Western" or "permissive" version allows motorists to turn right on a red signal after stopping unless prohibited by a sign. Many states adopted Western RTOR in the mid-1970's. The objectives of this study were to ases...

Changes in inertia and effect on turning effort across different wheelchair configurations.

PubMed

Caspall, Jayme J; Seligsohn, Erin; Dao, Phuc V; Sprigle, Stephen

2013-01-01

When executing turning maneuvers, manual wheelchair users must overcome the rotational inertia of the wheelchair system. Differences in wheelchair rotational inertia can result in increases in torque required to maneuver, resulting in greater propulsion effort and stress on the shoulder joints. The inertias of various configurations of an ultralightweight wheelchair were measured using a rotational inertia-measuring device. Adjustments in axle position, changes in wheel and tire type, and the addition of several accessories had various effects on rotational inertias. The configuration with the highest rotational inertia (solid tires, mag wheels with rearward axle) exceeded the configuration with the lowest (pneumatic tires, spoke wheels with forward axle) by 28%. The greater inertia requires increased torque to accelerate the wheelchair during turning. At a representative maximum acceleration, the reactive torque spanned the range of 11.7 to 15.0 N-m across the wheelchair configurations. At higher accelerations, these torques exceeded that required to overcome caster scrub during turning. These results indicate that a wheelchair's rotational inertia can significantly influence the torque required during turning and that this influence will affect active users who turn at higher speeds. Categorizing wheelchairs using both mass and rotational inertia would better represent differences in effort during wheelchair maneuvers.

Surface quality and topographic inspection of variable compliance part after precise turning

NASA Astrophysics Data System (ADS)

Nieslony, P.; Krolczyk, G. M.; Wojciechowski, S.; Chudy, R.; Zak, K.; Maruda, R. W.

2018-03-01

The paper presents the problem of precise turning of the mould parts with variable compliance and demonstrates a topographic inspection of the machined surface quality. The study was conducted for the cutting tools made of cemented carbide with coatings, in a range of variable cutting parameters. The long shaft with special axial hole, made of hardened 55NiCrMoV6 steel was selected as a workpiece. The carried out study included the stiffness measurement of the machining system, as well as the investigation of cutting force components. In this context, the surface topography parameters were evaluated using the stylus profile meter and analysed. The research revealed that the surface topography, alongside the 3D functional parameters, and PSD influences the performance of the machined surface. The lowest surface roughness parameters values, equalled to Sa = 1 μm and Sz = 4.3 μm have been obtained during turning with cutting speed vc = 90 m/min. The stable turning of variable compliance part affects the surface texture formation with a unidirectional perpendicular, anisotropic structure. Nevertheless, in case of unstable turning, the characteristic chatter marks are observed, and process dynamics has greater contribution in formation of surface finish than turning kinematics and elastic plastic deformation of workpiece.

Differences of Ballet Turns ("Pirouette") Performance between Experienced and Novice Ballet Dancers

ERIC Educational Resources Information Center

Lin, Chia-Wei; Chen, Shing-Jye; Su, Fong-Chin; Wu, Hong-Wen; Lin, Cheng-Feng

2014-01-01

Purpose: This study investigated the different postural control strategies exhibited by experienced and novice dancers in ballet turns ("pirouettes"). Method: Thirteen novice and 13 experienced dancers performed ballet turns with dominant-leg support. The peak push force was measured in the double-leg support phase. The inclination…

Aquatic turning performance of painted turtles (Chrysemys picta) and functional consequences of a rigid body design.

PubMed

Rivera, Gabriel; Rivera, Angela R V; Dougherty, Erin E; Blob, Richard W

2006-11-01

The ability to capture prey and avoid predation in aquatic habitats depends strongly on the ability to perform unsteady maneuvers (e.g. turns), which itself depends strongly on body flexibility. Two previous studies of turning performance in rigid-bodied taxa have found either high maneuverability or high agility, but not both. However, examinations of aquatic turning performance in rigid-bodied animals have had limited taxonomic scope and, as such, the effects of many body shapes and designs on aquatic maneuverability and agility have yet to be examined. Turtles represent the oldest extant lineage of rigid-bodied vertebrates and the only aquatic rigid-bodied tetrapods. We evaluated the aquatic turning performance of painted turtles, Chrysemys picta (Schneider, 1783) using the minimum length-specific radius of the turning path (R/L) and the average turning rate (omega(avg)) as measures of maneuverability and agility, respectively. We filmed turtles conducting forward and backward turns in an aquatic arena. Each type of turn was executed using a different pattern of limb movements. During forward turns, turtles consistently protracted the inboard forelimb and held it stationary into the flow, while continuing to move the outboard forelimb and both hindlimbs as in rectilinear swimming. The limb movements of backward turns were more complex than those of forward turns, but involved near simultaneous retraction and protraction of contralateral fore- and hindlimbs, respectively. Forward turns had a minimum R/L of 0.0018 (the second single lowest value reported from any animal) and a maximum omega(avg) of 247.1 degrees. Values of R/L for backward turns (0.0091-0.0950 L) were much less variable than that of forward turns (0.0018-1.0442 L). The maneuverability of turtles is similar to that recorded previously for rigid-bodied boxfish. However, several morphological features of turtles (e.g. shell morphology and limb position) appear to increase agility relative to the body

Bodies with noncircular cross sections and bank-to-turn missiles

NASA Technical Reports Server (NTRS)

Jackson, C. M., Jr.; Sawyer, W. C.

1986-01-01

An evaluation is made of prospective missile applications for noncircular cross section bodies, and of recent developments in bank-to-turn missile configuration aerodynamics. The discussion encompasses cross-flow analysis techniques, as well as study results obtained for bodies with elliptical and square cross sections and with variable cross sections. Attention is given to both the performance advantages and the stability and control problems of bank-to-turn missile configurations; the aerodynamic data presented for monoplanar configurations extend to those incorporating airbreathing propulsion systems.

Pigeons steer like helicopters and generate down- and upstroke lift during low speed turns.

PubMed

Ros, Ivo G; Bassman, Lori C; Badger, Marc A; Pierson, Alyssa N; Biewener, Andrew A

2011-12-13

Turning is crucial for animals, particularly during predator-prey interactions and to avoid obstacles. For flying animals, turning consists of changes in (i) flight trajectory, or path of travel, and (ii) body orientation, or 3D angular position. Changes in flight trajectory can only be achieved by modulating aerodynamic forces relative to gravity. How birds coordinate aerodynamic force production relative to changes in body orientation during turns is key to understanding the control strategies used in avian maneuvering flight. We hypothesized that pigeons produce aerodynamic forces in a uniform direction relative to their bodies, requiring changes in body orientation to redirect those forces to turn. Using detailed 3D kinematics and body mass distributions, we examined net aerodynamic forces and body orientations in slowly flying pigeons (Columba livia) executing level 90° turns. The net aerodynamic force averaged over the downstroke was maintained in a fixed direction relative to the body throughout the turn, even though the body orientation of the birds varied substantially. Early in the turn, changes in body orientation primarily redirected the downstroke aerodynamic force, affecting the bird's flight trajectory. Subsequently, the pigeon mainly reacquired the body orientation used in forward flight without affecting its flight trajectory. Surprisingly, the pigeon's upstroke generated aerodynamic forces that were approximately 50% of those generated during the downstroke, nearly matching the relative upstroke forces produced by hummingbirds. Thus, pigeons achieve low speed turns much like helicopters, by using whole-body rotations to alter the direction of aerodynamic force production to change their flight trajectory.

Pigeons steer like helicopters and generate down- and upstroke lift during low speed turns

PubMed Central

Ros, Ivo G.; Bassman, Lori C.; Badger, Marc A.; Pierson, Alyssa N.; Biewener, Andrew A.

2011-01-01

Turning is crucial for animals, particularly during predator–prey interactions and to avoid obstacles. For flying animals, turning consists of changes in (i) flight trajectory, or path of travel, and (ii) body orientation, or 3D angular position. Changes in flight trajectory can only be achieved by modulating aerodynamic forces relative to gravity. How birds coordinate aerodynamic force production relative to changes in body orientation during turns is key to understanding the control strategies used in avian maneuvering flight. We hypothesized that pigeons produce aerodynamic forces in a uniform direction relative to their bodies, requiring changes in body orientation to redirect those forces to turn. Using detailed 3D kinematics and body mass distributions, we examined net aerodynamic forces and body orientations in slowly flying pigeons (Columba livia) executing level 90° turns. The net aerodynamic force averaged over the downstroke was maintained in a fixed direction relative to the body throughout the turn, even though the body orientation of the birds varied substantially. Early in the turn, changes in body orientation primarily redirected the downstroke aerodynamic force, affecting the bird’s flight trajectory. Subsequently, the pigeon mainly reacquired the body orientation used in forward flight without affecting its flight trajectory. Surprisingly, the pigeon’s upstroke generated aerodynamic forces that were approximately 50% of those generated during the downstroke, nearly matching the relative upstroke forces produced by hummingbirds. Thus, pigeons achieve low speed turns much like helicopters, by using whole-body rotations to alter the direction of aerodynamic force production to change their flight trajectory. PMID:22123982

Ductile-regime turning of germanium and silicon

NASA Technical Reports Server (NTRS)

Blake, Peter N.; Scattergood, Ronald O.

1989-01-01

Single-point diamond turning of silicon and germanium was investigated in order to clarify the role of cutting depth in coaxing a ductile chip formation in normally brittle substances. Experiments based on the rapid withdrawal of the tool from the workpiece have shown that microfracture damage is a function of the effective depth of cut (as opposed to the nominal cutting depth). In essence, damage created by the leading edge of the tool is removed several revolutions later by lower sections of the tool edge, where the effective cutting depth is less. It appears that a truly ductile cutting response can be achieved only when the effective cutting depth, or critical chip thickness, is less than about 20 nm. Factors such as tool rake angle are significant in that they will affect the actual value of the critical chip thickness for transition from brittle to ductile response. It is concluded that the critical chip thickness is an excellent parameter for measuring the effects of machining conditions on the ductility of the cut and for designing tool-workpiece geometry in both turning and grinding.

Turn-taking: From perception to speech preparation.

PubMed

Wesselmeier, Hendrik; Müller, Horst M

2015-11-16

We investigated the preparation of a spoken answer response to interrogative sentences by measuring response time (RT) and the response-related readiness potential (RP). By comparing the RT and RP results we aimed to identify whether the RP-onset is more related to the actual speech preparation process or the pure intention to speak after turn-anticipation. Additionally, we investigated if the RP-onset can be influenced by the syntactic structure (one or two completion points). Therefore, the EEG data were sorted based on two variables: the cognitive load required for the response and the syntactic structure of the stimulus questions. The results of the response utterance preparation associated event-related potential (ERP) and the RT suggest that the RP-onset is more related to the actual speech preparation process rather than the pure intention to speak after turn-anticipation. However, the RP-onset can be influenced by the syntactic structure of the question leading to an early response preparation. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Memory boosts turn taking in evolutionary dilemma games.

PubMed

Wang, Tao; Chen, Zhigang; Yang, Lei; Zou, You; Luo, Juan

2015-05-01

Spontaneous turn taking phenomenon can be observed in many self-organized systems, and the mechanism is unclear. This paper tries to model it by evolutionary dilemma games with memory mechanism. Prisoner's dilemma, Snowdrift (including Leader and Hero) and Stag-hunt games are unified on an extended S-T plane. Agents play game with all the others and make decision by the last game histories. The experiments find that when agents remember last 2-step histories or more, a kind of cooperative turn taking (CAD) bursts at the area of Snowdrift game with restriction of S + T > 2R and S ≠ T, while the consistent strategy (DorC) gathers on the line of S + T > 2R and S = T. We also find that the system's fitness ratio greatly improved with 2-step memory. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

A Turn-Projected State-Based Conflict Resolution Algorithm

NASA Technical Reports Server (NTRS)

Butler, Ricky W.; Lewis, Timothy A.

2013-01-01

State-based conflict detection and resolution (CD&R) algorithms detect conflicts and resolve them on the basis on current state information without the use of additional intent information from aircraft flight plans. Therefore, the prediction of the trajectory of aircraft is based solely upon the position and velocity vectors of the traffic aircraft. Most CD&R algorithms project the traffic state using only the current state vectors. However, the past state vectors can be used to make a better prediction of the future trajectory of the traffic aircraft. This paper explores the idea of using past state vectors to detect traffic turns and resolve conflicts caused by these turns using a non-linear projection of the traffic state. A new algorithm based on this idea is presented and validated using a fast-time simulator developed for this study.

Page turning system

NASA Technical Reports Server (NTRS)

Kerley, James J. (Inventor); Eklund, Wayne D. (Inventor)

1992-01-01

A device for holding reading materials for use by readers without arm mobility is presented. The device is adapted to hold the reading materials in position for reading with the pages displayed to enable turning by use of a rubber tipped stick that is held in the mouth and has a pair of rectangular frames. The frames are for holding and positioning the reading materials opened in reading posture with the pages displayed at a substantially unobstructed sighting position for reading. The pair of rectangular frames are connected to one another by a hinge so the angle between the frames may be varied thereby varying the inclination of the reading material. A pair of bent spring mounted wires for holding opposing pages of the reading material open for reading without substantial visual interference of the pages is mounted to the base. The wires are also adjustable to the thickness of the reading material and have a variable friction adjustment. This enables the force of the wires against the pages to be varied and permits the reader to manipulate the pages with the stick.

Modeling of screening currents in coated conductor magnets containing up to 40000 turns

NASA Astrophysics Data System (ADS)

Pardo, E.

2016-08-01

Screening currents caused by varying magnetic fields degrade the homogeneity and stability of the magnetic fields created by REBCO coated conductor coils. They are responsible for the AC loss; which is also important for other power applications containing windings, such as transformers, motors and generators. Since real magnets contain coils exceeding 10000 turns, accurate modeling tools for this number of turns or above are necessary for magnet design. This article presents a fast numerical method to model coils with no loss of accuracy. We model a 10400-turn coil for its real number of turns and coils of up to 40000 turns with continuous approximation, which introduces negligible errors. The screening currents, the screening current induced field (SCIF) and the AC loss is analyzed in detail. The SCIF is at a maximum at the remnant state with a considerably large value. The instantaneous AC loss for an anisotropic magnetic-field dependent J c is qualitatively different than for a constant J c , although the loss per cycle is similar. Saturation of the magnetization currents at the end pancakes causes the maximum AC loss at the first ramp to increase with J c . The presented modeling tool can accurately calculate the SCIF and AC loss in practical computing times for coils with any number of turns used in real windings, enabling parameter optimization.

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 ...

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.

Mexican University Turns to U.S. for Students

ERIC Educational Resources Information Center

Campbell, Monica

2007-01-01

Latin America's largest university is now seeking students in the United States. Spotting a ripe market and a growing Hispanic population, the National Autonomous University of Mexico is steadily strengthening its foothold in the United States and Canada--one of the first inroads northward by a Latin American university. For decades the…

Effect of turning frequency on co-composting pig manure and fungus residue.

PubMed

Jiang-Ming, Zhou

2017-03-01

Composting of agricultural wastes not only can reduce environmental pollution caused by improper disposal, but also can recycle agricultural wastes and transform them into highly valuable products, such as fertilizers or soil conditioners, for agricultural applications. However, the composting process and final product are easily affected by the limited oxygen supply that results from insufficient aeration, especially in the center of a large-scale windrow. Hence, a pilot-scale experiment was conducted to investigate the effects of the turning frequency on the composting efficiency and compost quality of used pig manure and fungus residue. Physical and chemical characteristics were measured over the course of 63 days of composting. The data indicate that higher temperatures and more rapid moisture removal generally result from a turning treatment of once every 2-4 days than in fewer, or no, turning treatments. The total nitrogen, total phosphorus, and total potassium contents increased in all windrows as the organic matter content decreased, but both the increases and decrease were greater in windrows that were turned more frequently. The reduction of the organic matter mass by 53.7-66.0% for a turning of once every 2-8 days is significantly higher than that for the static windrow (39.1%). Although there is an increase in nitrogen mass loss with an increased turning frequency, lower nitrogen mass losses (12.7-25.7%) in all treatments were noted compared with previous studies. A final compost product with less moisture, less weight, higher nutrient content (N, P, and K), and greater stability was obtained in windrows with turning frequencies of once every 2-4 days, which is recommended when composting pig manure and fungus residue. Composting of agricultural wastes not only can reduce environmental pollution caused by improper disposal, but recycling of agricultural wastes transforms them into highly valuable products, such as fertilizers or soil conditioners, for

Winding a Long Coil with a Pre-Programmed Turns Density Variation

DTIC Science & Technology

1975-05-27

turns den- sity is to follow. A machine having this capability is needed to provide a towed ELF loop antenna with the smoothly tapered sensitivity...Introduction A submarine towed ELF loop antenna vibrates longitudinally and trans- versely during towing. The vibration is driven by the fluctuating surface...in attaining the smoothly varying turns density required for the signal winding of a towed ELF loop antenna . Acknowledgments Thanks are due to John

Variation in dual-task performance reveals late initiation of speech planning in turn-taking.

PubMed

Sjerps, Matthias J; Meyer, Antje S

2015-03-01

The smooth transitions between turns in natural conversation suggest that speakers often begin to plan their utterances while listening to their interlocutor. The presented study investigates whether this is indeed the case and, if so, when utterance planning begins. Two hypotheses were contrasted: that speakers begin to plan their turn as soon as possible (in our experiments less than a second after the onset of the interlocutor's turn), or that they do so close to the end of the interlocutor's turn. Turn-taking was combined with a finger tapping task to measure variations in cognitive load. We assumed that the onset of speech planning in addition to listening would be accompanied by deterioration in tapping performance. Two picture description experiments were conducted. In both experiments there were three conditions: (1) Tapping and Speaking, where participants tapped a complex pattern while taking over turns from a pre-recorded speaker, (2) Tapping and Listening, where participants carried out the tapping task while overhearing two pre-recorded speakers, and (3) Speaking Only, where participants took over turns as in the Tapping and Speaking condition but without tapping. The experiments differed in the amount of tapping training the participants received at the beginning of the session. In Experiment 2, the participants' eye-movements were recorded in addition to their speech and tapping. Analyses of the participants' tapping performance and eye movements showed that they initiated the cognitively demanding aspects of speech planning only shortly before the end of the turn of the preceding speaker. We argue that this is a smart planning strategy, which may be the speakers' default in many everyday situations. Copyright © 2014 Elsevier B.V. All rights reserved.

Body saccades of Drosophila consist of stereotyped banked turns.

PubMed

Muijres, Florian T; Elzinga, Michael J; Iwasaki, Nicole A; Dickinson, Michael H

2015-03-01

The flight pattern of many fly species consists of straight flight segments interspersed with rapid turns called body saccades, a strategy that is thought to minimize motion blur. We analyzed the body saccades of fruit flies (Drosophila hydei), using high-speed 3D videography to track body and wing kinematics and a dynamically scaled robot to study the production of aerodynamic forces and moments. Although the size, degree and speed of the saccades vary, the dynamics of the maneuver are remarkably stereotypic. In executing a body saccade, flies perform a quick roll and counter-roll, combined with a slower unidirectional rotation around their yaw axis. Flies regulate the size of the turn by adjusting the magnitude of torque that they produce about these control axes, while maintaining the orientation of the rotational axes in the body frame constant. In this way, body saccades are different from escape responses in the same species, in which the roll and pitch component of banking is varied to adjust turn angle. Our analysis of the wing kinematics and aerodynamics showed that flies control aerodynamic torques during the saccade primarily by adjusting the timing and amount of span-wise wing rotation. © 2015. Published by The Company of Biologists Ltd.

Method and apparatus for reducing sample dispersion in turns and junctions of microchannel systems

DOEpatents

Griffiths, Stewart K.; Nilson, Robert H.

2001-01-01

The performance of microchannel devices is improved by providing turns, wyes, tees, and other junctions that produce little dispersions of a sample as it traverses the turn or junction. The reduced dispersion results from contraction and expansion regions that reduce the cross-sectional area over some portion of the turn or junction. By carefully designing the geometries of these regions, sample dispersion in turns and junctions is reduced to levels comparable to the effects of ordinary diffusion. A numerical algorithm was employed to evolve low-dispersion geometries by computing the electric or pressure field within candidate configurations, sample transport through the turn or junction, and the overall effective dispersion. These devices should greatly increase flexibility in the design of microchannel devices by permitting the use of turns and junctions that do not induce large sample dispersion. In particular, the ability to fold electrophoretic and electrochrornatographic separation columns will allow dramatic improvements in the miniaturization of these devices. The low-lispersion devices are particularly suited to electrochromatographic and electrophoretic separations, as well as pressure-driven chromatographic separation. They are further applicable to microfluidic systems employing either electroosrnotic or pressure-driven flows for sample transport, reaction, mixing, dilution or synthesis.

Flight Tests on U.S.S. Los Angeles. Part I : Full Scale Pressure Distribution Investigation

NASA Technical Reports Server (NTRS)

De France, S J

1930-01-01

The primary purpose of this investigation was to obtain simultaneous data on the loads and stress experience in flight by the U. S. S. Los Angeles which could be used in rigid airship structure design. A secondary object of the investigation was to determine the turning and drag characteristics of the airship. The aerodynamic loading was obtained by measuring the pressure at 95 locations on the tail surfaces, 54 on the hull, and 5 on the passenger car. These measurements were made during a series of maneuvers consisting of turns and reversals in smooth air and during a cruise in rough air which was just short of squall proportions. The results of the pressure measurements on the hull indicate that the forces on the forebody of an airship are relatively small. The tail surface measurements show conclusively that the forces caused by gusts are much greater than those caused by horizontal maneuvers. In this investigation the tail surface loadings caused by gusts closely approached the designed loads of the tail structure. The turning and drag characteristics will be reported in separate reports.

CNC Turning Center Advanced Operations. Computer Numerical Control Operator/Programmer. 444-332.

ERIC Educational Resources Information Center

Skowronski, Steven D.; Tatum, Kenneth

This student guide provides materials for a course designed to introduce the student to the operations and functions of a two-axis computer numerical control (CNC) turning center. The course consists of seven units. Unit 1 presents course expectations and syllabus, covers safety precautions, and describes the CNC turning center components, CNC…

Turning Points during the Life of Student Project Teams: A Qualitative Study

ERIC Educational Resources Information Center

Raes, Elisabeth; Kyndt, Eva; Dochy, Filip

2015-01-01

In this qualitative study a more flexible alternative of conceptualising changes over time in teams is tested within student project teams. The conceptualisation uses turning points during the lifespan of a team to outline team development, based on work by Erbert, Mearns, & Dena (2005). Turning points are moments that made a significant…

Grip and limb force limits to turning performance in competition horses

PubMed Central

Tan, Huiling; Wilson, Alan M.

2011-01-01

Manoeuverability is a key requirement for successful terrestrial locomotion, especially on variable terrain, and is a deciding factor in predator–prey interaction. Compared with straight-line running, bend running requires additional leg force to generate centripetal acceleration. In humans, this results in a reduction in maximum speed during bend running and a published model assuming maximum limb force as a constraint accurately predicts how much a sprinter must slow down on a bend given his maximum straight-line speed. In contrast, greyhounds do not slow down or change stride parameters during bend running, which suggests that their limbs can apply the additional force for this manoeuvre. We collected horizontal speed and angular velocity of heading of horses while they turned in different scenarios during competitive polo and horse racing. The data were used to evaluate the limits of turning performance. During high-speed turns of large radius horizontal speed was lower on the bend, as would be predicted from a model assuming a limb force limit to running speed. During small radius turns the angular velocity of heading decreased with increasing speed in a manner consistent with the coefficient of friction of the hoof–surface interaction setting the limit to centripetal force to avoid slipping. PMID:21147799

Grip and limb force limits to turning performance in competition horses.

PubMed

Tan, Huiling; Wilson, Alan M

2011-07-22

Manoeuverability is a key requirement for successful terrestrial locomotion, especially on variable terrain, and is a deciding factor in predator-prey interaction. Compared with straight-line running, bend running requires additional leg force to generate centripetal acceleration. In humans, this results in a reduction in maximum speed during bend running and a published model assuming maximum limb force as a constraint accurately predicts how much a sprinter must slow down on a bend given his maximum straight-line speed. In contrast, greyhounds do not slow down or change stride parameters during bend running, which suggests that their limbs can apply the additional force for this manoeuvre. We collected horizontal speed and angular velocity of heading of horses while they turned in different scenarios during competitive polo and horse racing. The data were used to evaluate the limits of turning performance. During high-speed turns of large radius horizontal speed was lower on the bend, as would be predicted from a model assuming a limb force limit to running speed. During small radius turns the angular velocity of heading decreased with increasing speed in a manner consistent with the coefficient of friction of the hoof-surface interaction setting the limit to centripetal force to avoid slipping.

Right-­turn traffic volume adjustment in traffic signal warrant analysis : final report.

DOT National Transportation Integrated Search

2016-05-06

This report was based on the research project, Right-Turn Traffic Volume Adjustment in Traffic Signal Warrants, sponsored by the Nevada Department of Transportation (NDOT) and SOLARIS. Right-turn traffic does not affect intersection performance in th...

46 CFR 148.04-13 - Ferrous metal borings, shavings, turnings, or cuttings (excluding stainless steel).

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 5 2010-10-01 2010-10-01 false Ferrous metal borings, shavings, turnings, or cuttings... Requirements for Certain Material § 148.04-13 Ferrous metal borings, shavings, turnings, or cuttings (excluding... described as ferrous metal borings, shavings, turnings, or cuttings on board vessels (excluding stainless...

A Rationally Designed Reversible ‘Turn-Off’ Sensor for Glutathione

PubMed Central

Pei, Jinxin; Abell, Andrew D.

2017-01-01

γ-Glutamyl-cysteinyl-glycine (GSH) plays a critical role in maintaining redox homeostasis in biological systems and a decrease in its cellular levels is associated with diseases. Existing fluorescence-based chemosensors for GSH acts as irreversible reaction-based probes that exhibit a maximum fluorescence (‘turn-on’) once the reaction is complete, regardless of the actual concentration of GSH. A reversible, reaction-based ‘turn-off’ probe (1) is reported here to sense the decreasing levels of GSH, a situation known to occur at the onset of various diseases. The more fluorescent merocyanine (MC) isomer of 1 exists in aqueous solution and this reacts with GSH to induce formation of the ring-closed spiropyran (SP) isomer, with a measurable decrease in absorbance and fluorescence (‘turn-off’). Sensor 1 has good aqueous solubility and shows an excellent selectivity for GSH over other biologically relevant metal ions and aminothiol analytes. The sensor permeates HEK 293 cells and an increase in fluorescence is observed on adding buthionine sulfoximine, an inhibitor of GSH synthesis. PMID:28878194

Searching for Criteria in Evaluating the Monofin Swimming Turn from the Perspective of Coaching and Improving Technique

PubMed Central

Rejman, Marek; Borowska, Grażyna

2008-01-01

This study aims to analysise the selected kinematic parameters of the monofin swimming turn. The high complexity of performing turns is hindered by the large surface of the monofin, which disturbs control and sense of the body in water. A lack of objective data available on monofin swimming turns has resulted in field research connected with the specification of parameters needed for the evaluation of the technique. Therefore, turns observed in elite swimmers contain underlying conclusions for objective criteria, ensuring the highest level of coaching and the improving of turns in young swimmers. Six, high level, male swimmers participated in the study. The subject of the analysis was the fastest turn, from one out of three trial turns made after swimming a distance of 25 m. Images of the turns were collected from two cameras located under water in accordance with the procedures of the previous analyses of freestyle turns. The images were digitized and analysed by the SIMI®- Movement Analysis System. The interdependency of the total turn time and the remaining recorded parameters, constituted the basis for analysis of the kinematic parameters of five turn phases. The interdependency was measured using r- Pearson’s correlation coefficients. The novel character of the subject covered in this study, forced interpretation of the results on the basis of turn analyses in freestyle swimming. The results allow for the creation of a diagram outlinig area of search for an effective and efficient monofin swimming turn mechanism. The activities performed from the moment of wall contact until the commencement of stroking seem to be crucial for turn improvement. A strong belief has resulted that, the correct monofin swimming turn, is more than just a simple consequence of the fastest performance of all its components. The most important criteria in evaluating the quality of the monofin swimming turn are: striving for the optimal extension of wall contact time, push-off time

Looking for an accident: glider pilots' visual management and potentially dangerous final turns.

PubMed

Jarvis, Steve; Harris, Don

2007-06-01

Accidents caused by spinning from low turns continue to kill glider pilots despite the introduction of specific exercises aimed at increasing pilot awareness and recognition of this issue. In-cockpit video cameras were used to analyze flying accuracy and log the areas of visual interest of 36 qualified glider pilots performing final turns in a training glider. Pilots were found to divide their attention between four areas of interest: the view directly ahead; the landing area (right); the airspeed indicator; and an area between the direct ahead view and the landing area. The mean fixation rate was 85 shifts per minute. Significant correlations were found between over-use of rudder and a lack of attention to the view ahead, as well as between the overall fixation rate and poorer coordination in the turn. The results provide some evidence that a relationship exists between pilots' visual management and making turns in a potentially dangerous manner. Pilots who monitor the view ahead for reasonable periods during the final turn while not allowing their scan to become over-busy are those who are most likely to prevent a potential spin.

Estimating the Turn-around Radii of Six Isolated Galaxy Groups in the Local Universe

NASA Astrophysics Data System (ADS)

Lee, Jounghun

2018-03-01

Estimates of the turn-around radii of six isolated galaxy groups in the nearby universe are presented. From the Tenth Data Release of the Sloan Digital Sky Survey, we first select those isolated galaxy groups at redshifts z ≤ 0.05 in the mass range [0.3–1] × {10}14 {h}-1 {M}ȯ whose nearest-neighbor groups are located at distances larger than 15 times their virial radii. Then, we search for a gravitationally interacting web-like structure around each isolated group, which appears as an inclined streak pattern in the anisotropic spatial distribution of the neighboring field galaxies. Out of 59 isolated groups, only seven are found to possess such web-like structures in their neighbor zones, but one of them turns out to be NGC 5353/4, whose turn-around radius was already measured in a previous work and was thus excluded from our analysis. Applying the Turn-around Radius Estimator algorithm devised by Lee et al. to the identified web-like structures of the remaining six target groups, we determine their turn-around radii and show that three out of the six targets have larger turn-around radii than the spherical bound limit predicted by Planck cosmology. We discuss possible sources of the apparent violations of the three groups, including the underestimated spherical bound limit due to the approximation of the turn-around mass by the virial mass.

Turned versus anodised dental implants: a meta-analysis.

PubMed

Chrcanovic, B R; Albrektsson, T; Wennerberg, A

2016-09-01

The aim of this meta-analysis was to test the null hypothesis of no difference in the implant failure rates, marginal bone loss (MBL)and post-operative infection for patients being rehabilitated by turned versus anodised-surface implants, against the alternative hypothesis of a difference. An electronic search without time or language restrictions was undertaken in November 2015. Eligibility criteria included clinical human studies, either randomised or not. Thirty-eight publications were included. The results suggest a risk ratio of 2·82 (95% CI 1·95-4·06, P < 0·00001) for failure of turned implants, when compared to anodised-surface implants. Sensitivity analyses showed similar results when only the studies inserting implants in maxillae or mandibles were pooled. There were no statistically significant effects of turned implants on the MBL (mean difference-MD 0·02, 95%CI -0·16-0·20; P = 0·82) in comparison to anodised implants. The results of a meta-regression considering the follow-up period as a covariate suggested an increase of the MD with the increase in the follow-up time (MD increase 0·012 mm year(-1) ), however, without a statistical significance (P = 0·813). Due to lack of satisfactory information, meta-analysis for the outcome 'post-operative infection' was not performed. The results have to be interpreted with caution due to the presence of several confounding factors in the included studies. © 2016 John Wiley & Sons Ltd.

L&D Manual Turn Lane Storage Validation/Update

DOT National Transportation Integrated Search

2012-08-01

Queuing occurs at intersections mostly due to overflow or inadequacy of turn bays. The ODOT L&D : Manual Volume 1 has storage requirements for both signalized and unsignalized intersections. Figures : 401-9E and 401-10E of the L&D Manual provide the ...

Three-residue turns in alpha/beta-peptides and their application in the design of tertiary structures.

PubMed

Sharma, Gangavaram V M; Nagendar, Pendem; Ramakrishna, Kallaganti V S; Chandramouli, Nagula; Choudhary, Madavi; Kunwar, Ajit C

2008-06-02

A new three-residue turn was serendipitously discovered in alpha/beta hybrid peptides derived from alternating C-linked carbo-beta-amino acids (beta-Caa) and L-Ala residues. The three-residue beta-alpha-beta turn at the C termini, nucleated by a helix at the N termini, resulted in helix-turn (HT) supersecondary structures in these peptides. The turn in the HT motif is stabilized by two H bonds-CO(i-2)-NH(i), with a seven-membered pseudoring (gamma turn) in the backward direction, and NH(i-2)-CO(i), with a 13-membered pseudoring in the forward direction (i being the last residue)--at the C termini. The study was extended to generalize the new three-residue turn (beta-alpha-beta) by using different alpha- and beta-amino acids. Furthermore, the HT motifs were efficiently converted, by an extension with helical oligomers at the C termini, into peptides with novel helix-turn-helix (HTH) tertiary structures. However, this resulted in the destabilization of the beta-alpha-beta turn with the concomitant nucleation of another three-residue turn, alpha-beta-beta, which is stabilized by 11- and 15-membered bifurcated H bonds. Extensive NMR spectroscopic studies were carried out to delineate the secondary and tertiary structures in these peptides, which are further supported by molecular dynamics (MD) investigations.

Predicting beta-turns in proteins using support vector machines with fractional polynomials

PubMed Central

2013-01-01

Background β-turns are secondary structure type that have essential role in molecular recognition, protein folding, and stability. They are found to be the most common type of non-repetitive structures since 25% of amino acids in protein structures are situated on them. Their prediction is considered to be one of the crucial problems in bioinformatics and molecular biology, which can provide valuable insights and inputs for the fold recognition and drug design. Results We propose an approach that combines support vector machines (SVMs) and logistic regression (LR) in a hybrid prediction method, which we call (H-SVM-LR) to predict β-turns in proteins. Fractional polynomials are used for LR modeling. We utilize position specific scoring matrices (PSSMs) and predicted secondary structure (PSS) as features. Our simulation studies show that H-SVM-LR achieves Qtotal of 82.87%, 82.84%, and 82.32% on the BT426, BT547, and BT823 datasets respectively. These values are the highest among other β-turns prediction methods that are based on PSSMs and secondary structure information. H-SVM-LR also achieves favorable performance in predicting β-turns as measured by the Matthew's correlation coefficient (MCC) on these datasets. Furthermore, H-SVM-LR shows good performance when considering shape strings as additional features. Conclusions In this paper, we present a comprehensive approach for β-turns prediction. Experiments show that our proposed approach achieves better performance compared to other competing prediction methods. PMID:24565438

Predicting beta-turns in proteins using support vector machines with fractional polynomials.

PubMed

Elbashir, Murtada; Wang, Jianxin; Wu, Fang-Xiang; Wang, Lusheng

2013-11-07

β-turns are secondary structure type that have essential role in molecular recognition, protein folding, and stability. They are found to be the most common type of non-repetitive structures since 25% of amino acids in protein structures are situated on them. Their prediction is considered to be one of the crucial problems in bioinformatics and molecular biology, which can provide valuable insights and inputs for the fold recognition and drug design. We propose an approach that combines support vector machines (SVMs) and logistic regression (LR) in a hybrid prediction method, which we call (H-SVM-LR) to predict β-turns in proteins. Fractional polynomials are used for LR modeling. We utilize position specific scoring matrices (PSSMs) and predicted secondary structure (PSS) as features. Our simulation studies show that H-SVM-LR achieves Qtotal of 82.87%, 82.84%, and 82.32% on the BT426, BT547, and BT823 datasets respectively. These values are the highest among other β-turns prediction methods that are based on PSSMs and secondary structure information. H-SVM-LR also achieves favorable performance in predicting β-turns as measured by the Matthew's correlation coefficient (MCC) on these datasets. Furthermore, H-SVM-LR shows good performance when considering shape strings as additional features. In this paper, we present a comprehensive approach for β-turns prediction. Experiments show that our proposed approach achieves better performance compared to other competing prediction methods.

Structure change of β-hairpin induced by turn optimization: an enhanced sampling molecular dynamics simulation study.

PubMed

Shao, Qiang; Yang, Lijiang; Gao, Yi Qin

2011-12-21

Our previous study showed that for the tested polypeptides which have similar β-hairpin structures but different sequences, their folding free energy pathways are dominantly determined by the turn conformational propensity. In this study, we study how the turn conformational propensity affects the structure of hairpins. The folding of two mutants of GB1p peptide (GB1m2 and GB1m3), which have the optimized turn sequence ((6)DDATK(11)T → (6)NPATG(11)K) with native structures unsolved, were simulated using integrated tempering sampling molecular dynamics simulations and the predicted stable structures were compared to wild-type GB1p. It was observed that the turn optimization of GB1p generates a more favored 5-residue type I(') turn in addition to the 6-residue type I turn in wild-type GB1p. As a result two distinctly different hairpin structures are formed corresponding to the "misfolded" (M) and the "folded" (F) states. M state is a one-residue-shifted asymmetric β-hairpin structure whereas F state has the similar symmetric hairpin structure as wild-type GB1p. The formation of the favored type I(') turn has a small free energy barrier and leads to the shifted β-hairpin structure, following the modified "zipping" model. The presence of disfavored type I turn structure makes the folding of a β-hairpin consistent with the "hydrophobic-core-centric" model. On the other hand, the folding simulations on other two GB1p mutants (GB1r1 and GBr2), which have the position of the hydrophobic core cluster further away from the turn compared to wild-type GB1p, showed that moving the hydrophobic core cluster away from the turn region destabilizes but does not change the hairpin structure. Therefore, the present study showed that the turn conformational propensity is a key factor in affecting not only the folding pathways but also the stable structure of β-hairpins, and the turn conformational change induced by the turn optimization leads to significant changes of �

Quick-Turn Finite Element Analysis for Plug-and-Play Satellite Structures

DTIC Science & Technology

2007-03-01

produced from 0.375 inch round stock and turned on a machine lathe to achieve the shoulder feature and drilled to make it hollow. Figure 3.1...component, a linear taper was machined from the connection shoulder to the solar panel connecting fork. The part was then turned using the machine lathe ...utilizing a modern five-axis Computer Numerical Code ( CNC ) machine mill, the process time could be reduced by as much as seventy-five percent and the

Turning behaviour depends on frictional damping in the fruit fly Drosophila.

PubMed

Hesselberg, Thomas; Lehmann, Fritz-Olaf

2007-12-01

Turning behaviour in the fruit fly Drosophila depends on several factors including not only feedback from sensory organs and muscular control of wing motion, but also the mass moments of inertia and the frictional damping coefficient of the rotating body. In the present study we evaluate the significance of body friction for yaw turning and thus the limits of visually mediated flight control in Drosophila, by scoring tethered flies flying in a flight simulator on their ability to visually compensate a bias on a moving object and a visual background panorama at different simulated frictional dampings. We estimated the fly's natural damping coefficient from a numerical aerodynamic model based on both friction on the body and the flapping wings during saccadic turning. The model predicts a coefficient of 54 x 10(-12) Nm s, which is more than 100-times larger than the value estimated from a previous study on the body alone. Our estimate suggests that friction plays a larger role for yaw turning in Drosophila than moments of inertia. The simulator experiments showed that visual performance of the fruit fly collapses near the physical conditions estimated for freely flying animals, which is consistent with the suggested role of the halteres for flight stabilization. However, kinematic analyses indicate that the measured loss of flight control might be due predominantly to the limited fine control in the fly's steering muscles below a threshold of 1-2 degrees stroke amplitude, rather than resulting from the limits of visual motion detection by the fly's compound eyes. We discuss the impact of these results and suggest that the elevated frictional coefficient permits freely flying fruit flies to passively terminate rotational body movements without producing counter-torque during the second half of the saccadic turning manoeuvre.

Student Wellbeing and the Therapeutic Turn in Education

ERIC Educational Resources Information Center

Wright, Katie

2014-01-01

This article considers current concerns with promoting student mental health and wellbeing against the backdrop of critiques of the "therapeutic turn" in education. It begins by situating accounts of "therapeutic education" within broader theorisation of therapeutic culture. In doing so, the importance of this work is…

Genesis of a flexible turning center

NASA Astrophysics Data System (ADS)

Sanclemente, Paul; French, Robert D.

GE - Aircraft Engines has designed, built, and is operating a flexible turning center for jet engine hardware. Although the plant is in the forefront of manufacturing technology development, it was intended from the start to be a production facility. So while there was much to learn from being involved in all phases of the project, meeting production schedules was, and is, key to its success. This paper reviews the early history of the project and ends with a view of its recent production status.

Alchemical inflation: inflaton turns into Higgs

NASA Astrophysics Data System (ADS)

Nakayama, Kazunori; Takahashi, Fuminobu

2012-11-01

We propose a new inflation model in which a gauge singlet inflaton turns into the Higgs condensate after inflation. The inflationary path is characterized by a moduli space of supersymmetric vacua spanned by the inflaton and Higgs field. The inflation energy scale is related to the soft supersymmetry breaking, and the Hubble parameter during inflation is smaller than the gravitino mass. The initial condition for the successful inflation is naturally realized by the pre-inflation in which the Higgs plays a role of the waterfall field.

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.

Flocking and Turning: a New Model for Self-organized Collective Motion

NASA Astrophysics Data System (ADS)

Cavagna, Andrea; Del Castello, Lorenzo; Giardina, Irene; Grigera, Tomas; Jelic, Asja; Melillo, Stefania; Mora, Thierry; Parisi, Leonardo; Silvestri, Edmondo; Viale, Massimiliano; Walczak, Aleksandra M.

2015-02-01

Birds in a flock move in a correlated way, resulting in large polarization of velocities. A good understanding of this collective behavior exists for linear motion of the flock. Yet observing actual birds, the center of mass of the group often turns giving rise to more complicated dynamics, still keeping strong polarization of the flock. Here we propose novel dynamical equations for the collective motion of polarized animal groups that account for correlated turning including solely social forces. We exploit rotational symmetries and conservation laws of the problem to formulate a theory in terms of generalized coordinates of motion for the velocity directions akin to a Hamiltonian formulation for rotations. We explicitly derive the correspondence between this formulation and the dynamics of the individual velocities, thus obtaining a new model of collective motion. In the appropriate overdamped limit we recover the well-known Vicsek model, which dissipates rotational information and does not allow for polarized turns. Although the new model has its most vivid success in describing turning groups, its dynamics is intrinsically different from previous ones in a wide dynamical regime, while reducing to the hydrodynamic description of Toner and Tu at very large length-scales. The derived framework is therefore general and it may describe the collective motion of any strongly polarized active matter system.

Influence of daytime running lamps on visual reaction time of pedestrians when detecting turn indicators.

PubMed

Peña-García, Antonio; de Oña Lopez, Rocío; Espín Estrella, Antonio; Aznar Dols, Fernando; Calvo Poyo, Franscisco J; Molero Mesa, Evaristo; de Oña López, Juan

2010-10-01

This article describes one experiment that studied the influence of Daytime Running Lamps (DRL) on pedestrian detection of turn indicators. An experimental device including one DRL and one turn indicator was used in order to determine Visual Reaction Times (VRT) of 148 observers in different situations involving turn indicator activation. Such situations were combinations of three main variables: color of DRL, separation between DRL and Turn Indicator, and observation angle. Significant changes in VRT were found depending on the configurations above, especially the observation angle and the color of DRL. This second result demonstrates that amber DRLs inhibit the detection of Turn Indicators. One of the main targets of this paper is to recommend that carmakers introduce only white DRLs on new vehicles. We also intend to advise regulatory bodies working on automotive regulation about the consequences of allowing amber DRLs and also about the danger of introducing constrains on the distance between DRL and Turn Indicator without further experimental evidences. Copyright © 2010 Elsevier Ltd and National Safety Council. All rights reserved.

Required coefficient of friction in the anteroposterior and mediolateral direction during turning at different walking speeds

PubMed Central

Yamaguchi, Takeshi; Suzuki, Akito; Hokkirigawa, Kazuo

2017-01-01

This study investigated the required coefficient of friction (RCOF) and the tangent of center of mass (COM)–center of pressure (COP) angle in the mediolateral (ML) and anteroposterior (AP) directions during turning at different walking speeds. Sixteen healthy young adults (8 males and 8 females) participated in this study. The participants were instructed to conduct trials of straight walking and 90° step and spin turns to the right at each of three self-selected speeds (slow, normal, and fast). The ML and AP directions during turning gait were defined using the orientation of the pelvis to construct a body-fixed reference frame. The RCOF values and COM–COP angle tangent in the ML direction during turning at weight acceptance phase were higher than those during straight walking, and those values increased with increasing walking speed. The ML component of the RCOF and COM–COP tangent values during weight acceptance for step turns were higher than those for spin turns. The mean centripetal force during turning tended to increase with an increase in walking speed and had a strong positive correlation with the RCOF values in the ML direction (R = 0.97 during the weight acceptance phase; R = 0.95 during the push-off phase). Therefore, turning, particularly step turn, is likely to cause lateral slip at weight acceptance because of the increased centripetal force compared with straight walking. Future work should test at-risk population and compare with the present results. PMID:28640853

Required coefficient of friction in the anteroposterior and mediolateral direction during turning at different walking speeds.

PubMed

Yamaguchi, Takeshi; Suzuki, Akito; Hokkirigawa, Kazuo

2017-01-01

This study investigated the required coefficient of friction (RCOF) and the tangent of center of mass (COM)-center of pressure (COP) angle in the mediolateral (ML) and anteroposterior (AP) directions during turning at different walking speeds. Sixteen healthy young adults (8 males and 8 females) participated in this study. The participants were instructed to conduct trials of straight walking and 90° step and spin turns to the right at each of three self-selected speeds (slow, normal, and fast). The ML and AP directions during turning gait were defined using the orientation of the pelvis to construct a body-fixed reference frame. The RCOF values and COM-COP angle tangent in the ML direction during turning at weight acceptance phase were higher than those during straight walking, and those values increased with increasing walking speed. The ML component of the RCOF and COM-COP tangent values during weight acceptance for step turns were higher than those for spin turns. The mean centripetal force during turning tended to increase with an increase in walking speed and had a strong positive correlation with the RCOF values in the ML direction (R = 0.97 during the weight acceptance phase; R = 0.95 during the push-off phase). Therefore, turning, particularly step turn, is likely to cause lateral slip at weight acceptance because of the increased centripetal force compared with straight walking. Future work should test at-risk population and compare with the present results.

Prediction of beta-turns from amino acid sequences using the residue-coupled model.

PubMed

Guruprasad, K; Shukla, S

2003-04-01

We evaluated the prediction of beta-turns from amino acid sequences using the residue-coupled model with an enlarged representative protein data set selected from the Protein Data Bank. Our results show that the probability values derived from a data set comprising 425 protein chains yielded an overall beta-turn prediction accuracy 68.74%, compared with 94.7% reported earlier on a data set of 30 proteins using the same method. However, we noted that the overall beta-turn prediction accuracy using probability values derived from the 30-protein data set reduces to 40.74% when tested on the data set comprising 425 protein chains. In contrast, using probability values derived from the 425 data set used in this analysis, the overall beta-turn prediction accuracy yielded consistent results when tested on either the 30-protein data set (64.62%) used earlier or a more recent representative data set comprising 619 protein chains (64.66%) or on a jackknife data set comprising 476 representative protein chains (63.38%). We therefore recommend the use of probability values derived from the 425 representative protein chains data set reported here, which gives more realistic and consistent predictions of beta-turns from amino acid sequences.

Hard turning micro-machine tool

DOEpatents

DeVor, Richard E; Adair, Kurt; Kapoor, Shiv G

2013-10-22

A micro-scale apparatus for supporting a tool for hard turning comprises a base, a pivot coupled to the base, an actuator coupled to the base, and at least one member coupled to the actuator at one end and rotatably coupled to the pivot at another end. A tool mount is disposed on the at least one member. The at least one member defines a first lever arm between the pivot and the tool mount, and a second lever arm between the pivot and the actuator. The first lever arm has a length that is less than a length of the second lever arm. The actuator moves the tool mount along an arc.

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.

Luminescence of ferrocene-modified pyrene derivatives for turn-on sensing of Cu2 + and anions

NASA Astrophysics Data System (ADS)

Sun, Shuhua; Hu, Wenting; Gao, Hongfang; Qi, Honglan; Ding, Liping

2017-09-01

Detection and identification of metal ions by fluorescent turn-on sensors are challenging due to the quenching effect of most of the tested metal ions. In the present work, three ferrocene-modified pyrene-based probes 2-4 were synthesized to act as turn-on fluorescent sensors for Cu2 +. The measurements of fluorescence quantum yield and fluorescence lifetime reveal that ferrocenyl unit can efficiently reduce the fluorescence emission of pyrene moiety. Steady-state fluorescence measurements find that the three ferrocene-modified fluorophores exhibit selective turn-on responses to Cu2 +. Moreover, this turn-on effect to Cu2 + is highly influenced by the type of the counter ion. It is found that the presence of Cl- or NO3- could realize the turn-on response to Cu2 +, whereas, the presence of SO42 - or Ac- could not induce any fluorescence enhancement to Cu2 +. Control experiments with ferrocene-free pyrene-based probe 1 reveal that the ferrocenyl unit plays the key role in the turn-on response to Cu2 +. The possible mechanism for the turn-on responses is attributed to the oxidation behavior of Cu2 + to the ferrocene unit, which is confirmed by the control experiments with sodium ascorbate. Cyclic voltammetry measurements show that Cu2 + can influence the redox behaviors of ferrocenyl derivatives, which is also highly dependent on the anion of the copper salts. The influence of anion on the turn-on responses to Cu2 + was further used for anion detection and fluorescent logic gate.

Luminescence of ferrocene-modified pyrene derivatives for turn-on sensing of Cu2+ and anions.

PubMed

Sun, Shuhua; Hu, Wenting; Gao, Hongfang; Qi, Honglan; Ding, Liping

2017-09-05

Detection and identification of metal ions by fluorescent turn-on sensors are challenging due to the quenching effect of most of the tested metal ions. In the present work, three ferrocene-modified pyrene-based probes 2-4 were synthesized to act as turn-on fluorescent sensors for Cu 2+ . The measurements of fluorescence quantum yield and fluorescence lifetime reveal that ferrocenyl unit can efficiently reduce the fluorescence emission of pyrene moiety. Steady-state fluorescence measurements find that the three ferrocene-modified fluorophores exhibit selective turn-on responses to Cu 2+ . Moreover, this turn-on effect to Cu 2+ is highly influenced by the type of the counter ion. It is found that the presence of Cl - or NO 3 - could realize the turn-on response to Cu 2+ , whereas, the presence of SO 4 2- or Ac - could not induce any fluorescence enhancement to Cu 2+ . Control experiments with ferrocene-free pyrene-based probe 1 reveal that the ferrocenyl unit plays the key role in the turn-on response to Cu 2+ . The possible mechanism for the turn-on responses is attributed to the oxidation behavior of Cu 2+ to the ferrocene unit, which is confirmed by the control experiments with sodium ascorbate. Cyclic voltammetry measurements show that Cu 2+ can influence the redox behaviors of ferrocenyl derivatives, which is also highly dependent on the anion of the copper salts. The influence of anion on the turn-on responses to Cu 2+ was further used for anion detection and fluorescent logic gate. Copyright © 2017 Elsevier B.V. All rights reserved.

CNC Turning Technician. A Competency-Based Instructional System.

ERIC Educational Resources Information Center

Sloan, Kelly; Hilley, Robert

This competency-based curriculum guide for instructing students in using computer numerically controlled (CNC) turning machines is one of a series of instructional guides for the machinist field developed in Oklahoma. Although developed jointly with Baxter Technologies Corporation and oriented toward the Baxter Vo-Tec 2000 Future Builder CNC…

Structural Conversion of Aβ17–42 Peptides from Disordered Oligomers to U-Shape Protofilaments via Multiple Kinetic Pathways

PubMed Central

Cheon, Mookyung; Hall, Carol K.; Chang, Iksoo

2015-01-01

Discovering the mechanisms by which proteins aggregate into fibrils is an essential first step in understanding the molecular level processes underlying neurodegenerative diseases such as Alzheimer’s and Parkinson's. The goal of this work is to provide insights into the structural changes that characterize the kinetic pathways by which amyloid-β peptides convert from monomers to oligomers to fibrils. By applying discontinuous molecular dynamics simulations to PRIME20, a force field designed to capture the chemical and physical aspects of protein aggregation, we have been able to trace out the entire aggregation process for a system containing 8 Aβ17–42 peptides. We uncovered two fibrillization mechanisms that govern the structural conversion of Aβ17–42 peptides from disordered oligomers into protofilaments. The first mechanism is monomeric conversion templated by a U-shape oligomeric nucleus into U-shape protofilament. The second mechanism involves a long-lived and on-pathway metastable oligomer with S-shape chains, having a C-terminal turn, en route to the final U-shape protofilament. Oligomers with this C-terminal turn have been regarded in recent experiments as a major contributing element to cell toxicity in Alzheimer’s disease. The internal structures of the U-shape protofilaments from our PRIME20/DMD simulation agree well with those from solid state NMR experiments. The approach presented here offers a simple molecular-level framework to describe protein aggregation in general and to visualize the kinetic evolution of a putative toxic element in Alzheimer’s disease in particular. PMID:25955249

Diamond Turning Of Infra-Red Components

NASA Astrophysics Data System (ADS)

Hodgson, B.; Lettington, A. H.; Stillwell, P. F. T. C.

1986-05-01

Single point diamond machining of infra-red optical components such as aluminium mirrors, germanium lenses and zinc sulphide domes is potentially the most cost effective method for their manufacture since components may be machined from the blanks to a high surface finish, requiring no subsequent polishing, in a few minutes. Machines for the production of flat surfaces are well established. Diamond turning lathes for curved surfaces however require a high capital investment which can be justified only for research purposes or high volume production. The present paper describes the development of a low cost production machine based on a Bryant Symons diamond turning lathe which is able to machine spherical components to the required form and finish. It employs two horizontal spindles one for the workpiece the other for the tool. The machined radius of curvature is set by the alignment of the axes and the radius of the tool motion, as in conventional generation. The diamond tool is always normal to the workpiece and does not need to be accurately profiled. There are two variants of this basic machine. For machining hemispherical domes the axes are at right angles while for lenses with positive or negative curvature these axes are adjustable. An aspherical machine is under development, based on the all mechanical spherical machine, but in which a ± 2 mm aspherecity may be imposed on the best fit sphere by moving the work spindle under numerical control.

Electron capture by U(91+) and U(92+) and ionization of U(90+) and U(91+)

NASA Technical Reports Server (NTRS)

Gould, H.; Greiner, D.; Lindstrom, P.; Symons, T. J. M.; Crawford, H.

1984-01-01

U(92+)/U(91+) and U(91+)/U(90+) electron-capture and ionization cross sections and equilibrium charge-state distributions are measured experimentally in mylar, Cu and Ta of varying thickness. Relativistic U(68+) ions at 437 or 962 MeV/nucleon are produced by a heavy-ion linear accelerator and synchrotron in tandem and passed through the target material into a magnetic specrometer and position-sensitive proportional counter for evaluation of charge states. The results are presented graphically and discussed. At 962 MeV/nucleon, beams containing 85 percent bare U(92+) nuclei are obtained using 150-mg/sq cm Cu or 85-mg/sq cm Ta; at 437 MeV/nucleon, 50 percent bare U(92+) nuclei are obtained with 90-mg/sq cm Cu. The techniques decribed can be applied to produce beams of bare U nuclei for acceleration to ultrarelativistic speeds or beams of few-electron U for atomic-physics experiments on quantum electrodynamics.

Asymptotic freedom in certain S O (N ) and S U (N ) models

NASA Astrophysics Data System (ADS)

Einhorn, Martin B.; Jones, D. R. Timothy

2017-09-01

We calculate the β -functions for S O (N ) and S U (N ) gauge theories coupled to adjoint and fundamental scalar representations, correcting longstanding, previous results. We explore the constraints on N resulting from requiring asymptotic freedom for all couplings. When we take into account the actual allowed behavior of the gauge coupling, the minimum value of N in both cases turns out to be larger than realized in earlier treatments. We also show that in the large N limit, both models have large regions of parameter space corresponding to total asymptotic freedom.

Nanostructural Evolution of Hard Turning Layers in Carburized Steel

NASA Astrophysics Data System (ADS)

Bedekar, Vikram

The mechanisms of failure for components subjected to contact fatigue are sensitive to the structure and properties of the material surface. Although, the bulk material properties are determined by the steel making, forming and the heat treatment; the near surface material properties are altered during final material removal processes such as hard turning or grinding. Therefore, the ability to optimize, modulate and predict the near surface properties during final metal removal operations would be extremely useful in the enhancement of service life of a component. Hard machining is known to induce severely deformed layers causing dramatic microstructural transformations. These transformations occur via grain refinement or thermal phenomena depending upon cutting conditions. The aim of this work is to engineer the near surface nanoscale structure and properties during hard turning by altering strain, strain rate, temperature and incoming microstructure. The near surface material transformations due to hard turning were studied on carburized SAE 8620 bearing steel. Variations in parent material microstructures were introduced by altering the retained austenite content. The strain, strain rate and temperature achieved during final metal cutting were altered by varying insert geometry, insert wear and cutting speed. The subsurface evolution was quantified by a series of advanced characterization techniques such as transmission electron microscopy (TEM), glancing angle X-ray diffraction (GAXRD), X-ray stress evaluation and nanoindentation which were coupled with numerical modeling. Results showed that the grain size of the nanocrystalline near surface microstructure can be effectively controlled by altering the insert geometry, insert wear, cutting speed and the incoming microstructure. It was also evident that the near surface retained austenite decreased at lower cutting speed indicating transformation due to plastic deformation, while it increased at higher cutting

Predicting beta-turns and their types using predicted backbone dihedral angles and secondary structures.

PubMed

Kountouris, Petros; Hirst, Jonathan D

2010-07-31

Beta-turns are secondary structure elements usually classified as coil. Their prediction is important, because of their role in protein folding and their frequent occurrence in protein chains. We have developed a novel method that predicts beta-turns and their types using information from multiple sequence alignments, predicted secondary structures and, for the first time, predicted dihedral angles. Our method uses support vector machines, a supervised classification technique, and is trained and tested on three established datasets of 426, 547 and 823 protein chains. We achieve a Matthews correlation coefficient of up to 0.49, when predicting the location of beta-turns, the highest reported value to date. Moreover, the additional dihedral information improves the prediction of beta-turn types I, II, IV, VIII and "non-specific", achieving correlation coefficients up to 0.39, 0.33, 0.27, 0.14 and 0.38, respectively. Our results are more accurate than other methods. We have created an accurate predictor of beta-turns and their types. Our method, called DEBT, is available online at http://comp.chem.nottingham.ac.uk/debt/.

One for You, One for Me: Humans' Unique Turn-Taking Skills.

PubMed

Melis, Alicia P; Grocke, Patricia; Kalbitz, Josefine; Tomasello, Michael

2016-07-01

Long-term collaborative relationships require that any jointly produced resources be shared in mutually satisfactory ways. Prototypically, this sharing involves partners dividing up simultaneously available resources, but sometimes the collaboration makes a resource available to only one individual, and any sharing of resources must take place across repeated instances over time. Here, we show that beginning at 5 years of age, human children stabilize cooperation in such cases by taking turns across instances of obtaining a resource. In contrast, chimpanzees do not take turns in this way, and so their collaboration tends to disintegrate over time. Alternating turns in obtaining a collaboratively produced resource does not necessarily require a prosocial concern for the other, but rather requires only a strategic judgment that partners need incentives to continue collaborating. These results suggest that human beings are adapted for thinking strategically in ways that sustain long-term cooperative relationships and that are absent in their nearest primate relatives. © The Author(s) 2016.

Turning Points: Ideas in Books Affecting American Education.

ERIC Educational Resources Information Center

Parker, Franklin

Ideas in ten books which marked turning points in American educational directions are analyzed. William H. McGuffey's "Readers" (1836-44) set the moral and inspirational tone that still exists in American education, though now lessened and mainly in small-town America. "Medical Education in the United States and Canada"…

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...

Local sequence information in cellular retinoic acid-binding protein I: specific residue roles in beta-turns.

PubMed

Rotondi, Kenneth S; Gierasch, Lila M

2003-01-01

We have recently shown that two of the beta-turns (III and IV) in the ten-stranded, beta-clam protein, cellular retinoic acid-binding protein I (CRABP I), are favored in short peptide fragments, arguing that they are encoded by local interactions (K. S. Rotondi and L. M. Gierasch, Biochemistry, 2003, Vol. 42, pp. 7976-7985). In this paper we examine these turns in greater detail to dissect the specific local interactions responsible for their observed native conformational biases. Conformations of peptides corresponding to the turn III and IV fragments were examined under conditions designed to selectively disrupt stabilizing interactions, using pH variation, chaotrope addition, or mutagenesis to probe specific side-chain influences. We find that steric constraints imposed by excluded volume effects between near neighbor residues (i,i+2), favorable polar (i,i+2) interactions, and steric permissiveness of glycines are the principal factors accounting for the observed native bias in these turns. Longer-range stabilizing interactions across the beta-turns do not appear to play a significant role in turn stability in these short peptides, in contrast to their importance in hairpins. Additionally, our data add to a growing number of examples of the 3:5 type I turn with a beta-bulge as a class of turns with high propensity to form locally defined structure. Current work is directed at the interplay between the local sequence information in the turns and more long-range influences in the mechanism of folding of this predominantly beta-sheet protein. Copyright 2004 Wiley Periodicals, Inc.

The effects of processing and sequence organization on the timing of turn taking: a corpus study

PubMed Central

Roberts, Seán G.; Torreira, Francisco; Levinson, Stephen C.

2015-01-01

The timing of turn taking in conversation is extremely rapid given the cognitive demands on speakers to comprehend, plan and execute turns in real time. Findings from psycholinguistics predict that the timing of turn taking is influenced by demands on processing, such as word frequency or syntactic complexity. An alternative view comes from the field of conversation analysis, which predicts that the rules of turn-taking and sequence organization may dictate the variation in gap durations (e.g., the functional role of each turn in communication). In this paper, we estimate the role of these two different kinds of factors in determining the speed of turn-taking in conversation. We use the Switchboard corpus of English telephone conversation, already richly annotated for syntactic structure speech act sequences, and segmental alignment. To this we add further information including Floor Transfer Offset (the amount of time between the end of one turn and the beginning of the next), word frequency, concreteness, and surprisal values. We then apply a novel statistical framework (“random forests”) to show that these two dimensions are interwoven together with indexical properties of the speakers as explanatory factors determining the speed of response. We conclude that an explanation of the of the timing of turn taking will require insights from both processing and sequence organization. PMID:26029125

Spectroscopic evidence of β-turn in N-glycated peptidomimetics related to leucine-enkephalin

NASA Astrophysics Data System (ADS)

Vass, E.; Hollósi, M.; Kveder, M.; Kojić-Prodić, B.; Čudić, M.; Horvat, Š.

2000-11-01

The conformational differences caused by N-glycation of the amide bond in endogenous opioid pentapeptide leucine-enkephalin (Tyr-Gly-Gly-Phe-Leu) have been explored in solution using FTIR spectroscopy, NMR and molecular modelling. The compounds studied include protected and unprotected enkephalin analogues N-alkylated at the second (Gly 2) amino acid residue with a 6-deoxy- D-galactose moiety ( 1- 3). Comparison of the amide I component bands in the FTIR spectra, measured in trifluoroethanol (TFE), CHCl 3 and DMSO, revealed significant differences in the intensity as well as shifts in component band frequencies for glycopeptides 1- 3. We found that only the FTIR spectrum of the fully protected compound 1 indicated the presence of a higher population of β-turns, while the spectra of the partially protected and unprotected glycopeptides 2 and 3 reflected the dominance of unordered or open structures, with some low population of turns. The observed NOE connectivities in CDCl 3 for both isomers of the fully protected compound 1, the all-trans one and another with Tyr 1-Gly 2 peptide bond in cis conformation, indicate the presence of a β-like turn conformation. Molecular dynamics simulations of the glycopeptide 1 obtained by unconstrained energy minimization of trans- and cis- 1 shows that one of trans form conformations is consistent with β-turn whereas cis isomer has revealed less-compact turn.

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).

An oscillator model of the timing of turn-taking.

PubMed

Wilson, Margaret; Wilson, Thomas P

2005-12-01

When humans talk without conventionalized arrangements, they engage in conversation--that is, a continuous and largely nonsimultaneous exchange in which speakers take turns. Turn-taking is ubiquitous in conversation and is the normal case against which alternatives, such as interruptions, are treated as violations that warrant repair. Furthermore, turn-taking involves highly coordinated timing, including a cyclic rise and fall in the probability of initiating speech during brief silences, and involves the notable rarity, especially in two-party conversations, of two speakers' breaking a silence at once. These phenomena, reported by conversation analysts, have been neglected by cognitive psychologists, and to date there has been no adequate cognitive explanation. Here, we propose that, during conversation, endogenous oscillators in the brains of the speaker and the listeners become mutually entrained, on the basis of the speaker's rate of syllable production. This entrained cyclic pattern governs the potential for initiating speech at any given instant for the speaker and also for the listeners (as potential next speakers). Furthermore, the readiness functions of the listeners are counterphased with that of the speaker, minimizing the likelihood of simultaneous starts by a listener and the previous speaker. This mutual entrainment continues for a brief period when the speech stream ceases, accounting for the cyclic property of silences. This model not only captures the timing phenomena observed inthe literature on conversation analysis, but also converges with findings from the literatures on phoneme timing, syllable organization, and interpersonal coordination.

Assessing the interactions among U.S. climate policy, biomass energy, and agricultural trade

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

Wise, Marshall A.; McJeon, Haewon C.; Calvin, Katherine V.

Energy from biomass is potentially an important contributor to U.S. climate change mitigation efforts. However, an important consideration to large-scale implementation of bioenergy is that the production of biomass competes with other uses of land. This includes traditionally economically productive uses, such as agriculture and forest products, as well as storage of carbon in forests and non-commercial lands. In addition, in the future, biomass may be more easily traded, meaning that increased U.S. reliance on bioenergy could come with it greater reliance on imported energy. Several approaches could be implemented to address these issues, including limits on U.S. biomass importsmore » and protection of U.S. and global forests. This paper explores these dimensions of bioenergy’s role in U.S. climate policy and the relationship to these alternative measures for ameliorating the trade and land use consequences of bioenergy. It first demonstrates that widespread use of biomass in the U.S. could lead to imports; and it highlights that the relative stringency of domestic and international carbon mitigation policy will heavily influence the degree to which it is imported. Next, it demonstrates that while limiting biomass imports would prevent any reliance on other countries for this energy supply, it would most likely alter the balance of trade in other agricultural products against which biomass competes; for example, it might turn the U.S. from a corn exporter to a corn importer. Finally, it shows that increasing efforts to protect both U.S. and international forests could also affect the balance of trade in other agricultural products.« less

The Contribution of the Ontological Turn in Education: Some Methodological and Political Implications

ERIC Educational Resources Information Center

Zembylas, Michalinos

2017-01-01

This paper follows recent debates on the ontological turn in the social sciences and humanities to exemplify how this turn creates important openings of methodological and political potential in education. In particular, the paper makes an attempt to show two things: first, the new questions and possibilities that are opened from explicitly…

Simulation on turning aspheric surface method via oscillating feed

NASA Astrophysics Data System (ADS)

Kong, Fanxing; Li, Zengqiang; Sun, Tao

2014-08-01

It is quite difficult to manufacturing optical components, the combination of high gradient ellipsoid and hyperboloid, with high machining surface requirements. To solve the problem, in this paper we present a turning and forming method via oscillating feed of R-θ layout lathe, analyze machining ellipsoid segment and hyperboloid segment separately through oscillating feed. Also calculate parameters on each trajectory during processing respectively and obtain displacement, velocity, acceleration and other parameters. The simulation result shows that this rotary turning method is capable of ensuring that the cutter is on the equidistance line of meridian cross section curve of work piece during processing high gradient aspheric surface, which helps getting high quality surface. Also the method provides a new approach and a theory basis for manufacturing high quality aspheric surface and extending function of the available twin-spindle lathe as well.

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.

Predicting β-turns and their types using predicted backbone dihedral angles and secondary structures

PubMed Central

2010-01-01

Background β-turns are secondary structure elements usually classified as coil. Their prediction is important, because of their role in protein folding and their frequent occurrence in protein chains. Results We have developed a novel method that predicts β-turns and their types using information from multiple sequence alignments, predicted secondary structures and, for the first time, predicted dihedral angles. Our method uses support vector machines, a supervised classification technique, and is trained and tested on three established datasets of 426, 547 and 823 protein chains. We achieve a Matthews correlation coefficient of up to 0.49, when predicting the location of β-turns, the highest reported value to date. Moreover, the additional dihedral information improves the prediction of β-turn types I, II, IV, VIII and "non-specific", achieving correlation coefficients up to 0.39, 0.33, 0.27, 0.14 and 0.38, respectively. Our results are more accurate than other methods. Conclusions We have created an accurate predictor of β-turns and their types. Our method, called DEBT, is available online at http://comp.chem.nottingham.ac.uk/debt/. PMID:20673368

Comparison of Different Methods of Grading a Level Turn Task on a Flight Simulator

NASA Technical Reports Server (NTRS)

Heath, Bruce E.; Crier, tomyka

2003-01-01

With the advancements in the computing power of personal computers, pc-based flight simulators and trainers have opened new avenues in the training of airplane pilots. It may be desirable to have the flight simulator make a quantitative evaluation of the progress of a pilot's training thereby reducing the physical requirement of the flight instructor who must, in turn, watch every flight. In an experiment, University students conducted six different flights, each consisting of two level turns. The flights were three minutes in duration. By evaluating videotapes, two certified flight instructors provided separate letter grades for each turn. These level turns were also evaluated using two other computer based grading methods. One method determined automated grades based on prescribed tolerances in bank angle, airspeed and altitude. The other method used was deviations in altitude and bank angle for performance index and performance grades.

Relationship between linear velocity and tangential push force while turning to change the direction of the manual wheelchair.

PubMed

Hwang, Seonhong; Lin, Yen-Sheng; Hogaboom, Nathan S; Wang, Lin-Hwa; Koontz, Alicia M

2017-08-28

Wheelchair propulsion is a major cause of upper limb pain and injuries for manual wheelchair users with spinal cord injuries (SCIs). Few studies have investigated wheelchair turning biomechanics on natural ground surfaces. The purpose of this study was to investigate the relationship between tangential push force and linear velocity of the wheelchair during the turning portions of propulsion. Using an instrumented handrim, velocity and push force data were recorded for 25 subjects while they propel their own wheelchairs on a concrete floor along a figure-eight-shaped course at a maximum velocity. The braking force (1.03 N) of the inside wheel while turning was the largest of all other push forces (p<0.05). Larger changes in squared velocity while turning were significantly correlated with higher propulsive and braking forces used at the pre-turning, turning, and post-turning phases (p<0.05). Subjects with less change of velocity while turning needed less braking force to maneuver themselves successfully and safely around the turns. Considering the magnitude and direction of tangential force applied to the wheel, it seems that there are higher risks of injury and instability for upper limb joints when braking the inside wheel to turn. The results provide insight into wheelchair setup and mobility skills training for wheelchair users.

Differences of ballet turns (pirouette) performance between experienced and novice ballet dancers.

PubMed

Lin, Chia-Wei; Chen, Shing-Jye; Su, Fong-Chin; Wu, Hong-Wen; Lin, Cheng-Feng

2014-09-01

This study investigated the different postural control strategies exhibited by experienced and novice dancers in ballet turns (pirouettes). Thirteen novice and 13 experienced dancers performed ballet turns with dominant-leg support. The peak push force was measured in the double-leg support phase. The inclination angles of rotation axis with respect to vertical axis were calculated in the early single-leg support phase as well as the initiation sequence of ankle, knee, and hip joints on the supporting leg. Moreover, the anchoring index of the head was computed in the transverse plane during turning. The novice dancers applied a greater push force, an increased inclination angle of rotation axis, and an insufficient proximal-to-distal extension sequence pattern. The novice dancers also had a smaller head-anchoring index compared with experienced dancers, which meant novice dancers were not using a space target as a stability reference. A poorer performance in novice dancers could result from higher push force in propulsion, lack of a "proximal-to-distal extension sequence" pattern, and lack of visual spotting for postural stability. Training on sequential initiation of lower-extremity joints and rehearsal of visual spotting are essential for novice dancers to obtain better performance on ballet turns.

Turn-taking in cooperative offspring care: by-product of individual provisioning behavior or active response rule?

PubMed

Savage, James L; Browning, Lucy E; Manica, Andrea; Russell, Andrew F; Johnstone, Rufus A

2017-01-01

For individuals collaborating to rear offspring, effective organization of resource delivery is difficult because each carer benefits when the others provide a greater share of the total investment required. When investment is provided in discrete events, one possible solution is to adopt a turn-taking strategy whereby each individual reduces its contribution rate after investing, only increasing its rate again once another carer contributes. To test whether turn-taking occurs in a natural cooperative care system, here we use a continuous time Markov model to deduce the provisioning behavior of the chestnut-crowned babbler ( Pomatostomus ruficeps ), a cooperatively breeding Australian bird with variable number of carers. Our analysis suggests that turn-taking occurs across a range of group sizes (2-6), with individual birds being more likely to visit following other individuals than to make repeat visits. We show using a randomization test that some of this apparent turn-taking arises as a by-product of the distribution of individual inter-visit intervals ("passive" turn-taking) but that individuals also respond actively to the investment of others over and above this effect ("active" turn-taking). We conclude that turn-taking in babblers is a consequence of both their individual provisioning behavior and deliberate response rules, with the former effect arising through a minimum interval required to forage and travel to and from the nest. Our results reinforce the importance of considering fine-scale investment dynamics when studying parental care and suggest that behavioral rules such as turn-taking may be more common than previously thought. Caring for offspring is a crucial stage in the life histories of many animals and often involves conflict as each carer typically benefits when others contribute a greater share of the work required. One way to resolve this conflict is to monitor when other carers contribute and adopt a simple "turn-taking" rule to ensure

Optimization of cutting parameters for machining time in turning process

NASA Astrophysics Data System (ADS)

Mavliutov, A. R.; Zlotnikov, E. G.

2018-03-01

This paper describes the most effective methods for nonlinear constraint optimization of cutting parameters in the turning process. Among them are Linearization Programming Method with Dual-Simplex algorithm, Interior Point method, and Augmented Lagrangian Genetic Algorithm (ALGA). Every each of them is tested on an actual example – the minimization of production rate in turning process. The computation was conducted in the MATLAB environment. The comparative results obtained from the application of these methods show: The optimal value of the linearized objective and the original function are the same. ALGA gives sufficiently accurate values, however, when the algorithm uses the Hybrid function with Interior Point algorithm, the resulted values have the maximal accuracy.

Birds and dolphins flock to turn basin in feeding frenzy.

NASA Technical Reports Server (NTRS)

2000-01-01

The water in the turn basin, east of the Vehicle Assembly Building and next to the crawlerway, teems with fish and draws white pelicans, gray pelicans, cormorants, sea gulls and more looking for a meal. The turn basin is part of the Indian River Lagoon, composed of Mosquito Lagoon to the north, Banana River and Creek to the south and the Indian River to the west. The Indian River Lagoon has one of the most diverse bird populations anywhere in America. Also, nearly one-third of the nation's manatee population lives here or migrates through the lagoon seasonally. The lagoon varies in width from .5 mile to 5 miles and averages only 3 feet in depth.

The Purpose of Mess in Action Research: Building Rigour though a Messy Turn

ERIC Educational Resources Information Center

Cook, Tina

2009-01-01

Mess and rigour might appear to be strange bedfellows. This paper argues that the purpose of mess is to facilitate a turn towards new constructions of knowing that lead to transformation in practice (an action turn). Engaging in action research--research that can disturb both individual and communally held notions of knowledge for practice--will…

X-31 in flight - Herbst Turn

NASA Technical Reports Server (NTRS)

1995-01-01

and thrust vectoring, and airflow phenomena at high angles of attack. This understanding is expected to lead to design methods that provide better maneuverability in future high performance aircraft and make them safer to fly. An international test organization of about 110 people, managed by the Advanced Research Projects Agency (ARPA), conducted the flight operations at NASA Dryden. The ARPA had requested flight research for the X-31 aircraft be moved there in February 1992. In addition to ARPA and NASA, the international test organization (ITO) included the U.S. Navy, the U.S. Air Force, Rockwell International, the Federal Republic of Germany, and Daimler-Benz Aerospace (formerly Messerschmitt-Bolkow-Blohm and Deutsche Aerospace). NASA was responsible for flight research operations, aircraft maintenance, and research engineering once the program moved to Dryden. The No. 1 X-31 aircraft was lost in an accident January 19, 1995. The pilot, Karl Heinz-Lang, of the Federal Republic of Germany, ejected safely before the aircraft crashed in an unpopulated desert area just north of Edwards. The X-31 program logged an X-plane record of 580 flights during the program, including 555 research missions and 21 in Europe for the 1995 Paris Air Show. A total of 14 pilots representing all agencies of the ITO flew the aircraft. This 32-second clip shows the aircraft at the top of a stall and then thrust vectoring itself around to attain a new heading, thereby allowing the aircraft to gain the advantage over a putative opponent in air-to-air combat. This maneuver is also known as a 'J turn.'

Redesigning the type II' β-turn in green fluorescent protein to type I': implications for folding kinetics and stability.

PubMed

Madan, Bharat; Sokalingam, Sriram; Raghunathan, Govindan; Lee, Sun-Gu

2014-10-01

Both Type I' and Type II' β-turns have the same sense of the β-turn twist that is compatible with the β-sheet twist. They occur predominantly in two residue β-hairpins, but the occurrence of Type I' β-turns is two times higher than Type II' β-turns. This suggests that Type I' β-turns may be more stable than Type II' β-turns, and Type I' β-turn sequence and structure can be more favorable for protein folding than Type II' β-turns. Here, we redesigned the native Type II' β-turn in GFP to Type I' β-turn, and investigated its effect on protein folding and stability. The Type I' β-turns were designed based on the statistical analysis of residues in natural Type I' β-turns. The substitution of the native "GD" sequence of i+1 and i+2 residues with Type I' preferred "(N/D)G" sequence motif increased the folding rate by 50% and slightly improved the thermodynamic stability. Despite the enhancement of in vitro refolding kinetics and stability of the redesigned mutants, they showed poor soluble expression level compared to wild type. To overcome this problem, i and i + 3 residues of the designed Type I' β-turn were further engineered. The mutation of Thr to Lys at i + 3 could restore the in vivo soluble expression of the Type I' mutant. This study indicates that Type II' β-turns in natural β-hairpins can be further optimized by converting the sequence to Type I'. © 2014 Wiley Periodicals, Inc.

Determination of Turning Characteristics of an Airship by Means of a Camera Obscura

NASA Technical Reports Server (NTRS)

Crowley, J W , Jr; Freeman, R G

1925-01-01

This investigation was carried out by the National Advisory Committee at Langley Field for the purpose of determining the adaptability of the camera obscura to the securing of turning characteristics of airships, and also of obtaining some of those characteristics of the C-7 airship. The method consisted in flying the airship in circling flight over a camera obscura and photographing it at known time intervals. The results show that the method used is highly satisfactory and that for the particular maneuver employed the turning diameter is 1,240 feet, corresponding to a turning coefficient of 6.4, and that the position of zero angle of yaw is at the nose of the airship.

Virtual Rover Takes its First Turn

NASA Image and Video Library

2004-01-13

This image shows a screenshot from the software used by engineers to drive the Mars Exploration Rover Spirit. The software simulates the rover's movements across the martian terrain, helping to plot a safe course for the rover. The virtual 3-D world around the rover is built from images taken by Spirit's stereo navigation cameras. Regions for which the rover has not yet acquired 3-D data are represented in beige. This image depicts the state of the rover before it backed up and turned 45 degrees on Sol 11 (01-13-04). http://photojournal.jpl.nasa.gov/catalog/PIA05063

Generation of vertical angular momentum in single, double, and triple-turn pirouette en dehors in ballet.

PubMed

Kim, Jemin; Wilson, Margaret A; Singhal, Kunal; Gamblin, Sarah; Suh, Cha-Young; Kwon, Young-Hoo

2014-09-01

The purpose of this study was to investigate the vertical angular momentum generation strategies used by skilled ballet dancers in pirouette en dehors. Select kinematic parameters of the pirouette preparation (stance depth, vertical center-of-mass motion range, initial shoulder line position, shoulder line angular displacement, and maximum trunk twist angle) along with vertical angular momentum parameters during the turn (maximum momentums of the whole body and body parts, and duration and rate of generation) were obtained from nine skilled collegiate ballet dancers through a three-dimensional motion analysis and compared among three turn conditions (single, double, and triple). A one-way ('turn') multivariate analysis of variance of the kinematic parameters and angular momentum parameters of the whole body and a two-way analysis of variance ('turn' × 'body') of the maximum angular momentums of the body parts were conducted. Significant 'turn' effects were observed in the kinematic/angular momentum parameters (both the preparation and the turn) (p <  0.05). As the number of turns increased, skilled dancers generated larger vertical angular momentums by predominantly increasing the rate of momentum generation using rotation of the upper trunk and arms. The trail (closing) arm showed the largest contribution to whole-body angular momentum followed by the lead arm.

Negotiating towards a next turn: phonetic resources for 'doing the same'.

PubMed

Sikveland, Rein Ove

2012-03-01

This paper investigates hearers' use of response tokens (back-channels), in maintaining and differentiating their actions. Initial observations suggest that hearers produce a sequence of phonetically similar responses to disengage from the current topic, and dissimilar responses to engage with the current topic. This is studied systematically by combining detailed interactional and phonetic analysis in a collection of naturally-occurring talk in Norwegian. The interactional analysis forms the basis for labeling actions as maintained ('doing the same') and differentiated ('NOT doing the same'), which is then used as a basis for phonetic analysis. The phonetic analysis shows that certain phonetic characteristics, including pitch, loudness, voice quality and articulatory characteristics, are associated with 'doing the same', as different from 'NOT doing the same'. Interactional analysis gives further evidence of how this differentiation is of systematic relevance in the negotiations of a next turn. This paper addresses phonetic variation and variability by focusing on the relationship between sequence and phonetics in the turn-by-turn development of meaning. This has important implications for linguistic/phonetic research, and for the study of back-channels.

Field Application of 238U/235U Measurements To Detect Reoxidation and Mobilization of U(IV).

PubMed

Jemison, Noah E; Shiel, Alyssa E; Johnson, Thomas M; Lundstrom, Craig C; Long, Philip E; Williams, Kenneth H

2018-03-20

Biostimulation to induce reduction of soluble U(VI) to relatively immobile U(IV) is an effective strategy for decreasing aqueous U(VI) concentrations in contaminated groundwater systems. If oxidation of U(IV) occurs following the biostimulation phase, U(VI) concentrations increase, challenging the long-term effectiveness of this technique. However, detecting U(IV) oxidation through dissolved U concentrations alone can prove difficult in locations with few groundwater wells to track the addition of U to a mass of groundwater. We propose the 238 U/ 235 U ratio of aqueous U as an independent, reliable tracer of U(IV) remobilization via oxidation or mobilization of colloids. Reduction of U(VI) produces 238 U-enriched U(IV), whereas remobilization of solid U(IV) should not induce isotopic fractionation. The incorporation of remobilized U(IV) with a high 238 U/ 235 U ratio into the aqueous U(VI) pool produces an increase in 238 U/ 235 U of aqueous U(VI). During several injections of nitrate to induce U(IV) oxidation, 238 U/ 235 U consistently increased, suggesting 238 U/ 235 U is broadly applicable for detecting mobilization of U(IV).

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...

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.

Turning and Radius Deviation Correction for a Hexapod Walking Robot Based on an Ant-Inspired Sensory Strategy

PubMed Central

Guo, Tong; Liu, Qiong; Zhu, Qianwei; Zhao, Xiangmo; Jin, Bo

2017-01-01

In order to find a common approach to plan the turning of a bio-inspired hexapod robot, a locomotion strategy for turning and deviation correction of a hexapod walking robot based on the biological behavior and sensory strategy of ants. A series of experiments using ants were carried out where the gait and the movement form of ants was studied. Taking the results of the ant experiments as inspiration by imitating the behavior of ants during turning, an extended turning algorithm based on arbitrary gait was proposed. Furthermore, after the observation of the radius adjustment of ants during turning, a radius correction algorithm based on the arbitrary gait of the hexapod robot was raised. The radius correction surface function was generated by fitting the correction data, which made it possible for the robot to move in an outdoor environment without the positioning system and environment model. The proposed algorithm was verified on the hexapod robot experimental platform. The turning and radius correction experiment of the robot with several gaits were carried out. The results indicated that the robot could follow the ideal radius and maintain stability, and the proposed ant-inspired turning strategy could easily make free turns with an arbitrary gait. PMID:29168742

Turning and Radius Deviation Correction for a Hexapod Walking Robot Based on an Ant-Inspired Sensory Strategy.

PubMed

Zhu, Yaguang; Guo, Tong; Liu, Qiong; Zhu, Qianwei; Zhao, Xiangmo; Jin, Bo

2017-11-23

Abstract : In order to find a common approach to plan the turning of a bio-inspired hexapod robot, a locomotion strategy for turning and deviation correction of a hexapod walking robot based on the biological behavior and sensory strategy of ants. A series of experiments using ants were carried out where the gait and the movement form of ants was studied. Taking the results of the ant experiments as inspiration by imitating the behavior of ants during turning, an extended turning algorithm based on arbitrary gait was proposed. Furthermore, after the observation of the radius adjustment of ants during turning, a radius correction algorithm based on the arbitrary gait of the hexapod robot was raised. The radius correction surface function was generated by fitting the correction data, which made it possible for the robot to move in an outdoor environment without the positioning system and environment model. The proposed algorithm was verified on the hexapod robot experimental platform. The turning and radius correction experiment of the robot with several gaits were carried out. The results indicated that the robot could follow the ideal radius and maintain stability, and the proposed ant-inspired turning strategy could easily make free turns with an arbitrary gait.

Selective detection of trace nitroaromatic, nitramine, and nitrate ester explosive residues using a three-step fluorimetric sensing process: a tandem turn-off, turn-on sensor.

PubMed

Sanchez, Jason C; Toal, Sarah J; Wang, Zheng; Dugan, Regina E; Trogler, William C

2007-11-01

Detection of trace quantities of explosive residues plays a key role in military, civilian, and counter-terrorism applications. To advance explosives sensor technology, current methods will need to become cheaper and portable while maintaining sensitivity and selectivity. The detection of common explosives including trinitrotoluene (TNT), cyclotrimethylenetrinitramine, cyclotetramethylene-tetranitramine, pentaerythritol tetranitrate, 2,4,6-trinitrophenyl-N-methylnitramine, and trinitroglycerin may be carried out using a three-step process combining "turn-off" and "turn-on" fluorimetric sensing. This process first detects nitroaromatic explosives by their quenching of green luminescence of polymetalloles (lambda em approximately 400-510 nm). The second step places down a thin film of 2,3-diaminonaphthalene (DAN) while "erasing" the polymetallole luminescence. The final step completes the reaction of the nitramines and/or nitrate esters with DAN resulting in the formation of a blue luminescent traizole complex (lambda(em) = 450 nm) providing a "turn-on" response for nitramine and nitrate ester-based explosives. Detection limits as low as 2 ng are observed. Solid-state detection of production line explosives demonstrates the applicability of this method to real world situations. This method offers a sensitive and selective detection process for a diverse group of the most common high explosives used in military and terrorist applications today.

Diplomas Count 2013: Second Chances--Turning Dropouts into Graduates

ERIC Educational Resources Information Center

Education Week, 2013

2013-01-01

The 2013 edition of "Diplomas Count," entitled "Second Chances: Turning Dropouts into Graduates," examines dropout recovery and innovative strategies for returning to the educational fold the 1 million students who leave school without a diploma each year. "Education Week's" journalists investigate interventions that…

Numerical modelling of tool wear in turning with cemented carbide cutting tools

NASA Astrophysics Data System (ADS)

Franco, P.; Estrems, M.; Faura, F.

2007-04-01

A numerical model is proposed for analysing the flank and crater wear resulting from the loss of material on cutting tool surface in turning processes due to wear mechanisms of adhesion, abrasion and fracture. By means of this model, the material loss along cutting tool surface can be analysed, and the worn surface shape during the workpiece machining can be determined. The proposed model analyses the gradual degradation of cutting tool during turning operation, and tool wear can be estimated as a function of cutting time. Wear-land width (VB) and crater depth (KT) can be obtained for description of material loss on cutting tool surface, and the effects of the distinct wear mechanisms on surface shape can be studied. The parameters required for the tool wear model are obtained from bibliography and experimental observation for AISI 4340 steel turning with WC-Co cutting tools.

Test and study on mirror quality of ultra-precision diamond turning

NASA Astrophysics Data System (ADS)

Chang, Yanyan; Sun, Tao; Li, Zengqiang; Wu, Baosen

2014-09-01

Using the diamond turning lathe and mono crystalline diamond tool, the aluminum alloy of 2A12 was cut under different cutting parameters including cutting speed, feed rate and depth of cut and the mirror surfaces were made. The surface roughness, micro hardness and residual stress of the mirror surface were tested by the surface profiler, the universal hardness tester and X-stress Robot. The influences of the cutting parameters on the mirror quality were studied. The research results have theoretical and practical significance to the selection of the optimal cutting parameters in ultraprecision diamond turning.

Turning movements, vehicle offsets and ageing drivers driving behaviour at channelized and unchannelized intersections.

PubMed

Choi, Jaisung; Tay, Richard; Kim, Sangyoup; Jeong, Seungwon

2017-11-01

Ageing drivers experience a higher risk of intersection crashes because of their decrease in driving efficiency, including the decline in cognitive ability, head and neck flexibility, and visual acuity. Although several studies have been conducted to examine the factors associated with ageing driver crashes at intersections, little research has been conducted to examine the differences in the factors related to ageing drivers' turning paths and intersection geometric features. This study aims to improve the safety of ageing drivers at intersections by identifying the maneuvers that are risky for them and tracking their turning movements at selected intersections. We find that ageing drivers experience more crashes at intersections than younger drivers, especially crashes involving turning movements. Furthermore, ageing drivers experience more crashes at unchannelized intersections compared to channelized intersections. In addition, this study finds that ageing drivers exhibit greater and more inconsistent offsets during turning movements compared to those of younger drivers at both channelized and unchannelized intersections. Ageing drivers also tend to make relatively sharper or tighter turns than younger drivers. Hence, transportation engineers and road safety professionals should consider appropriate countermeasures to reduce the risks of crashes involving ageing drivers at intersections. Copyright © 2017 Elsevier Ltd. All rights reserved.

As the Egg Turns: Monitoring Egg Attendance Behavior in Wild Birds Using Novel Data Logging Technology

PubMed Central

Shaffer, Scott A.; Clatterbuck, Corey A.; Kelsey, Emma C.; Naiman, Alex D.; Young, Lindsay C.; VanderWerf, Eric A.; Warzybok, Pete; Bradley, Russell; Jahncke, Jaime; Bower, Geoff C.

2014-01-01

Egg turning is unique to birds and critical for embryonic development in most avian species. Technology that can measure changes in egg orientation and temperature at fine temporal scales (1 Hz) was neither readily available nor small enough to fit into artificial eggs until recently. Here we show the utility of novel miniature data loggers equipped with 3-axis (i.e., triaxial) accelerometers, magnetometers, and a temperature thermistor to study egg turning behavior in free-ranging birds. Artificial eggs containing egg loggers were deployed in the nests of three seabird species for 1–7 days of continuous monitoring. These species (1) turned their eggs more frequently (up to 6.5 turns h−1) than previously reported for other species, but angular changes were often small (1–10° most common), (2) displayed similar mean turning rates (ca. 2 turns h−1) despite major differences in reproductive ecology, and (3) demonstrated distinct diurnal cycling in egg temperatures that varied between 1.4 and 2.4°C. These novel egg loggers revealed high-resolution, three-dimensional egg turning behavior heretofore never measured in wild birds. This new form of biotechnology has broad applicability for addressing fundamental questions in avian breeding ecology, life history, and development, and can be used as a tool to monitor birds that are sensitive to disturbance while breeding. PMID:24887441

The turning point in the number of traffic fatalities: two hypotheses about changes in underlying trends.

PubMed

Brüde, Ulf; Elvik, Rune

2015-01-01

The number of traffic fatalities reached a peak in many highly motorised countries around 1970. Some previous studies have suggested that the turning point in the number of traffic fatalities was inevitable and did not reflect a change in the underlying trends influencing the number of traffic fatalities. Other studies suggest that trends in traffic growth and fatality rate changed from before to after the turning point. This paper proposes two hypotheses about the turning point in the number of traffic fatalities. One hypothesis is that the long-term trends in traffic growth and fatality rate were the same before and after the turning point. The other hypothesis is that the long-term trends in traffic growth and fatality rate were different before and after the turning point was reached, in particular that the annual percentage decline in fatality rate became greater after the turning point than before. Such a change would suggest that road safety policy became more effective. Analysis of data for six countries (Denmark, Great Britain, Netherlands, Norway, Sweden, United States) lends stronger support to the latter hypothesis than to the former. The lesson for policy makers, in particular in countries where the number of traffic fatalities is still growing, is that they should not expect a turning point to be reached without policy interventions. Copyright © 2014 Elsevier Ltd. All rights reserved.

Wheelchair pushing and turning: lumbar spine and shoulder loads and recommended limits.

PubMed

Weston, Eric B; Khan, Safdar N; Marras, William S

2017-12-01

The objective of this study was to determine how simulated manual wheelchair pushing influences biomechanical loading to the lumbar spine and shoulders. Sixty-two subjects performed simulated wheelchair pushing and turning in a laboratory. An electromyography-assisted biomechanical model was used to estimate spinal loads. Moments at the shoulder joint, external hand forces and net turning torque were also assessed. Multiple linear regression techniques were employed to develop biomechanically based wheelchair pushing guidelines relating resultant hand force or net torque to spinal load. Male subjects experienced significantly greater spinal loading (p < 0.01), and spine loads were also increased for wheelchair turning compared to straight wheelchair pushing (p < 0.001). Biomechanically determined maximum acceptable resultant hand forces were 17-18% lower than psychophysically determined limits. We conclude that manual wheelchair pushing and turning can pose biomechanical risk to the lumbar spine and shoulders. Psychophysically determined maximum acceptable push forces do not appear to be protective enough of this biomechanical risk. Practitioner Summary: This laboratory study investigated biomechanical risk to the low back and shoulders during simulated wheelchair pushing. Manual wheelchair pushing posed biomechanical risk to the lumbar spine (in compression and A/P shear) and to the shoulders. Biomechanically determined wheelchair pushing thresholds are presented and are more protective than the closest psychophysically determined equivalents.

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.

The turn-of-the-century drought in North America: The new normal?

NASA Astrophysics Data System (ADS)

Schwalm, C. R.; Williams, C. A.; Schaefer, K. M.; NACP Site Synthesis Team

2011-12-01

At the turn of the century, from 2000 to 2004, western North America (25°-50°N, 100°-125°W) experienced a severe drought with far reaching consequences for the terrestrial biosphere. We quantified the drought's water and carbon cycle implications using upscaled flux tower data, observed and simulated fluxes from the NACP Site Synthesis, remote sensing products, weather reanalysis, crop yield, and river discharge. During the turn of the century drought we found a widespread drydown of the terrestrial biosphere, large decreases in river discharge and greenness, and a ~10% loss in cropland productivity. At the footprint scale carbon uptake declined with an anomalous carbon source of 0.11 Pg C/yr integrated over the full domain. Flux towers also recorded a clear signal of reduced latent and increased sensible heat fluxes, apart from grasslands. Dendrochronological reconstructions of drought extent, duration, and severity, based on the Palmer Drought Severity Index drought metric, indicated that the turn of the century drought was unprecedented since 1200 CE. Predicted changes in precipitation and drought, based on the CMIP3 multi-model mean, could permanently disable the weak sink (NEE = -0.19 Pg C/yr) in western North America by the midpoint of the 21st Century. Projections indicate the turn-of-the-century drought will be wet compared to the latter half of the 21st Century.

Turning frequency in adult bedridden patients to prevent hospital-acquired pressure ulcer: A scoping review.

PubMed

Jocelyn Chew, H-S; Thiara, Emelia; Lopez, Violeta; Shorey, Shefaly

2018-04-01

The aim of this study was to identify current research on turning frequencies of adult bed-bound patients and inform future turning practices for hospitals based on evidence-based practice. We undertook a scoping review framework that provided a transparent and systematic methodology using 8 electronic databases (CINAHL, PubMed, Cochrane Library, ScienceDirect, PsycINFO, Scopus, ProQuest, and Web of Science) to identify articles published from 2000 to 2016. Articles were included if they focused on the prevention of hospital-acquired pressure ulcers related to the frequency of turning or repositioning of bed-bound patients. Literature search and data extraction were performed independently by 3 authors. The study followed the PRISMA guidelines. In total, 911 articles were identified, of which 10 were eligible. Of the eligible articles, 8 studies could not reach a conclusion on the effective frequency of turning and duration for repositioning patients to prevent the development of pressure ulcers. Only 2 studies found significant differences among the intervention and control groups. Results regarding turning and repositioning schedules are inconclusive; however, the topic needs further exploration to improve the outdated guidelines surrounding pressure ulcer prevention. This may, in turn, make the work of nurses more efficient and make treatment cost-effective for both the patients and the hospitals. © 2017 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

Development and preliminary testing of an automatic turning movements identification system : final report, February 2010.

DOT National Transportation Integrated Search

2010-02-01

It is important for many applications, such as intersection delay estimation and adaptive signal : control, to obtain vehicle turning movement information at signalized intersections. However, : vehicle turning movement information is very time consu...

TURNS - A free-wake Euler/Navier-Stokes numerical method for helicopter rotors

NASA Technical Reports Server (NTRS)

Srinivasan, G. R.; Baeder, J. D.

1993-01-01

Computational capabilities of a numerical procedure, called TURNS (transonic unsteady rotor Navier-Stokes), to calculate the aerodynamics and acoustics (high-speed impulsive noise) out to several rotor diameters are summarized. The procedure makes it possible to obtain the aerodynamics and acoustics information in one single calculation. The vortical wave and its influence, as well as the acoustics, are captured as part of the overall flowfield solution. The accuracy and suitability of the TURNS method is demonstrated through comparisons with experimental data.

U.S. truck driver anthropometric study and multivariate anthropometric models for cab designs.

PubMed

Guan, Jinhua; Hsiao, Hongwei; Bradtmiller, Bruce; Kau, Tsui-Ying; Reed, Matthew R; Jahns, Steven K; Loczi, Josef; Hardee, H Lenora; Piamonte, Dominic Paul T

2012-10-01

This study presents data from a large-scale anthropometric study of U.S. truck drivers and the multivariate anthropometric models developed for the design of next-generation truck cabs. Up-to-date anthropometric information of the U.S. truck driver population is needed for the design of safe and ergonomically efficient truck cabs. We collected 35 anthropometric dimensions for 1,950 truck drivers (1,779 males and 171 females) across the continental United States using a sampling plan designed to capture the appropriate ethnic, gender, and age distributions of the truck driver population. Truck drivers are heavier than the U.S.general population, with a difference in mean body weight of 13.5 kg for males and 15.4 kg for females. They are also different in physique from the U.S. general population. In addition, the current truck drivers are heavier and different in physique compared to their counterparts of 25 to 30 years ago. The data obtained in this study provide more accurate anthropometric information for cab designs than do the current U.S. general population data or truck driver data collected 25 to 30 years ago. Multivariate anthropometric models, spanning 95% of the current truck driver population on the basis of a set of 12 anthropometric measurements, have been developed to facilitate future cab designs. The up-to-date truck driver anthropometric data and multivariate anthropometric models will benefit the design of future truck cabs which, in turn, will help promote the safety and health of the U.S. truck drivers.

The architecture of the spliceosomal U4/U6.U5 tri-snRNP

PubMed Central

Nguyen, Thi Hoang Duong; Galej, Wojciech P.; Bai, Xiao-chen; Savva, Christos G.; Newman, Andrew J.; Scheres, Sjors H. W.; Nagai, Kiyoshi

2015-01-01

U4/U6.U5 tri-snRNP is a 1.5 MDa pre-assembled spliceosomal complex comprising U5 snRNA, extensively base-paired U4/U6 snRNAs and >30 proteins, including the key components Prp8, Brr2 and Snu114. The tri-snRNP combines with a pre-mRNA substrate bound to U1 and U2 snRNPs and transforms into a catalytically active spliceosome following extensive compositional and conformational changes triggered by unwinding of the U4/U6 snRNAs. CryoEM single-particle reconstruction of yeast tri-snRNP at 5.9Å resolution reveals the essentially complete organization of its RNA and protein components. The single-stranded region of U4 snRNA between its 3′-stem-loop and the U4/U6 snRNA stem I is loaded into the Brr2 helicase active site ready for unwinding. Snu114 and the N-terminal domain of Prp8 position U5 snRNA to insert its Loop I, which aligns the exons for splicing, into the Prp8 active site cavity. The structure provides crucial insights into the activation process and the active site of the spliceosome. PMID:26106855

The postmodern turn in group therapy.

PubMed

O'Leary, J V

2001-10-01

The postmodern critique, often referred to as social constructionism, has influenced nearly all disciplines, including recently the domain of psychology--and most particularly psychoanalysis. This article presents an exposition of the "postmodern turn," including some historical perspective, a description of its theoretical elements as related to psychological practice, as well as standard objections to its theories. This author believes that many of the concepts inherent to a social constructionist approach are compelling for theory and practice in group therapy. Clinical case studies are cited in describing how postmodern theories present a natural fit for group therapy. Furthermore, specific implications of this model are delineated for the arduous task of leading groups.

Method And Apparatus For Reducing Sample Dispersion In Turns And Junctions Of Micro-Channel Systems

DOEpatents

Griffiths, Stewart K. , Nilson, Robert H.

2004-05-11

What is disclosed pertains to improvement in the performance of microchannel devices by providing turns, wyes, tees, and other junctions that produce little dispersion of a sample as it traverses the turn or junction. The reduced dispersion results from contraction and expansion regions that reduce the cross-sectional area over some portion of the turn or junction. By carefully designing the geometries of these regions, sample dispersion in turns and junctions is reduced to levels comparable to the effects of ordinary diffusion. The low dispersion features are particularly suited for microfluidic devices and systems using either electromotive force, pressure, or combinations thereof as the principle of fluid transport. Such microfluidic devices and systems are useful for separation of components, sample transport, reaction, mixing, dilution or synthesis, or combinations thereof.

Development of a 1000V, 200A, low-loss, fast-switching, gate-assisted turn-off thyristor

NASA Technical Reports Server (NTRS)

Schlegel, E. S.; Lowry, L. R.

1975-01-01

Feasibility was demonstrated for a thyristor that blocks 1000V forward and reverse, conducts 200A, and turns on in little more than 2 microsec with only 2A of gate drive. Its features include a turn-off time of 3 microsec achieved with 2A of gate assist current of a few microseconds duration and an energy dissipation of only 12 mJ per pulse for a 20 microsec half sine wave, 200A pulse. Extensive theoretical and experimental study of the electrical behavior of thyristors having a fast turn-off time have significantly improved the understanding of the physics of turning thyristor off. Thyristors of two new designs were fabricated and evaluated. The high speed and low power were achieved by a combination of gate amplification, cathode shunting, and gate-assisted turn-off. Two techniques for making this combination practical are described.

Hatching success of ostrich eggs in relation to setting, turning and angle of rotation.

PubMed

van Schalkwyk, S J; Cloete, S W; Brown, C R; Brand, Z

2000-03-01

1. Three trials were designed to study the effects of axis of setting, turning frequency and axis and angle of rotation on the hatching success of ostrich eggs. The joint effects of axis of setting and angle of rotation were investigated in a fourth trial. 2. The hatchability of fertile ostrich eggs artificially incubated in electronic incubators (turned through 60 degrees hourly) was improved substantially in eggs set in horizontal positions for 2 or 3 weeks and vertically for the rest of the time. 3. The hatchability of fertile eggs set in the horizontal position without any turning was very low (27%). It was improved to approximately 60% by manual turning through 180 degrees around the short axis and through 60 degrees around the long axis at 08.00 and 16.00 h. A further improvement to approximately 80% was obtained in eggs automatically turned through 60 degrees around the long axis in the incubator. Additional turning through 180 degrees around the short axis twice daily at 08.00 and 16.00 h resulted in no further improvement. 4. The hatchability of fertile eggs set vertically in electronic incubators and rotated hourly through angles ranging from 60 degrees to 90 degrees around the short axis increased linearly over the range studied. The response amounted to 1.83% for an increase of 10 (R2=0.96). 5. The detrimental effect of rotation through the smaller angle of 60 degrees around the short axis could be compensated for by setting ostrich eggs in the horizontal position for 2 weeks before putting them in the vertical position.

Leveraging finances for public health system improvement: results from the Turning Point initiative.

PubMed

Bekemeier, Betty; Riley, Catharine M; Berkowitz, Bobbie

2007-01-01

Reforming the public health infrastructure requires substantial system changes at the state level; state health agencies, however, often lack the resources and support for strategic planning and systemwide improvement. The Turning Point Initiative provided support for states to focus on large-scale system changes that resulted in increased funding for public health capacity and infrastructure development. Turning Point provides a test case for obtaining financial and institutional resources focused on systems change and infrastructure development-areas for which it has been historically difficult to obtain long-term support. The purpose of this exploratory, descriptive survey research was to enumerate the actual resources leveraged toward public health system improvement through the partnerships, planning, and implementation activities funded by the Robert Wood Johnson Foundation as a part of the Turning Point Initiative.

Right-Turn Traffic Volume Adjustments in Traffic Signal Warrant Analysis

DOT National Transportation Integrated Search

2015-01-01

To accomplish this research, a comprehensive literature review of existing guidelines and findings based on national and local studies was conducted. Ultimately, guidelines for consistent application for adjusting right-turn traffic volumes were deve...

Burnishing rolling process of the surface prepared in the turning process

NASA Astrophysics Data System (ADS)

Kulakowska, Agnieszka; Kukielka, Leon; Kaldunski, Pawel; Bohdal, Lukasz; Patyk, Radoslaw; Chodor, Jaroslaw; Kukielka, Krzysztof

2018-05-01

The aim of this article is to demonstrate the possibility of using burnishing rolling process as the technology of product development. The experimental researches were carried out, showing the ability to form the surface layer of the product with the desired properties. First, during turning rolling the surfaces of the samples were prepared. Then, the surfaces were burnished. The influence of turning process on the state of the surface layer parameters of C45 steel shafts are shown. Among the examined aspects the surface roughness, nano-roughness, material bearing, surface microstructure, metallographic structure were considered. Numerical simulation were conducted. Conclusions from the experiments and simulation were given.

Landing Gear/Soil Interaction Development of Criteria for Aircraft Operation on Soil During Turning and High Speed Straight Roll

DTIC Science & Technology

1974-01-01

system and does not permit differential thrust during turning. Turning Geometry and Force Analysis An aircraft with a castered -steerable nose wheel ...instantaneous radius of turn S= caster angle of nose wheel The definition of the turning angle and the development of side loads and longitudinal drag...pneumatic trail distance will vary with the turning angle, 0. It is alao possible that for a castered wheel , that the caster axis is displaced from the

A Rhetoric of Turns: Signs and Symbols in Education

ERIC Educational Resources Information Center

Rutten, Kris; Soetaert, Ronald

2014-01-01

In our research and teaching we explore the value and the place of rhetoric in education. From a theoretical perspective we situate our work in different disciplines, inspired by major "turns": linguistic, cultural, anthropological/ethnographic, interpretive, semiotic, narrative, literary, rhetorical etc. In this article we engage in the…

Birds and dolphins flock to turn basin in feeding frenzy.

NASA Technical Reports Server (NTRS)

2000-01-01