Science.gov

Sample records for 12-kilovolt kv overhead

  1. Final joint environmental assessment for the construction and routine operation of a 12-kilovolt (KV) overhead powerline right-of-way, and formal authorization for a 10-inch and 8-inch fresh water pipeline right-of-way, Naval Petroleum Reserve No. 1, Kern County, California

    SciTech Connect

    Not Available

    1994-10-01

    The purpose and need of the proposed action, which is the installation of an overhead powerline extension from an Naval Petroleum Reserve No. 1 (NPR-1) power source to the WKWD Station A, is to significantly reduce NPR-1`s overall utility costs. While the proposed action is independently justified on its own merits and is not tied to the proposed NPR-1 Cogeneration Facility, the proposed action would enable DOE to tie the NPR-1 fresh water pumps at Station A into the existing NPR-1 electrical distribution system. With the completion of the cogeneration facility in late 1994 or early 1995, the proposed action would save additional utility costs. This report deals with the environmental impacts of the construction of the powerline and the water pipeline. In addition, information is given about property rights and attaining permission to cross the property of proposed affected owners.

  2. Increasing the reliability of the shutdown of 500 - 750-kV overhead lines equipped with shunt reactors in an unsuccessful three-phase automatic repeated closure cycle

    SciTech Connect

    Kuz'micheva, K. I.; Merzlyakov, A. S.; Fokin, G. G.

    2013-05-15

    The reasons for circuit-breaker failures during repeated disconnection of 500 - 750 kV overhead lines with shunt reactors in a cycle of unsuccessful three-phase automatic reconnection (TARC) are analyzed. Recommendations are made for increasing the operating reliability of power transmission lines with shunt reactors when there is unsuccessful reconnection.

  3. a Distance Protection Strategic Spare Relay for 132/66 kv Overhead Lines

    NASA Astrophysics Data System (ADS)

    Harris, R. T.; Roberts, A. G.; Marks, A.; Phipps, W.

    2010-06-01

    The South African electrical supply utility (Eskom) has been experiencing problems in the field of protection, maintenance and in-service breakdowns which influence the quality of electrical supply to the consumer, an important and integral component of the utility business. As a result, further development of the generic relay, implemented as a strategic spare relay for the replacement of several schemes operating within Eskom's southern region has been initiated. These include the electromechanical, solid state and numerical distance protection relays and scheme failures on the 132/66 kV feeder network. The research considers the development, testing and configuration of the strategic spare relay in terms of software and peripheral hardware for the input and output terminal connections, generic equations and settings, for the purpose of scheme replacements. The various schemes are assessed for stepped distance and permissive intertripping for three and single pole operation. This is done in conjunction with the internal and external circuit diagrams to understand the detailed operation of the scheme and to ensure the effective implementation of the strategic spare relay. The generic relay is configured for the emergency replacement of the various schemes during in-service breakdowns. This constitutes a temporary installation and therefore the downtime of all the distance protection schemes that require replacement, is limited to a minimum.

  4. Power System Reliability Assessment by Analysing Voltage Dips on the Blue Horizon Bay 22KV Overhead Line in the Nelson Mandela Bay Municipality

    NASA Astrophysics Data System (ADS)

    Lamour, B. G.; Harris, R. T.; Roberts, A. G.

    2010-06-01

    Power system reliability problems are very difficult to solve because the power systems are complex and geographically widely distributed and influenced by numerous unexpected events. It is therefore imperative to employ the most efficient optimization methods in solving the problems relating to reliability of the power system. This paper presents a reliability analysis and study of the power interruptions resulting from severe power outages in the Nelson Mandela Bay Municipality (NMBM), South Africa and includes an overview of the important factors influencing reliability, and methods to improve the reliability. The Blue Horizon Bay 22 kV overhead line, supplying a 6.6 kV residential sector has been selected. It has been established that 70% of the outages, recorded at the source, originate on this feeder.

  5. OVERHEAD PROJECTION.

    ERIC Educational Resources Information Center

    HARTSELL, HORACE C.; VEENENDAAL, W.L.

    THE OVERHEAD PROJECTOR WAS DESIGNED TO FILL A RECOGNIZED NEED IN VISUAL COMMUNICATION. IT IS A TRANSPARENT, STILL PROJECTOR CAPABLE OF ENLARGING UP TO 10" X 10" TRANSPARENCIES. BY LOCATING THE PROJECTOR AT THE FRONT OF THE CLASSROOM ITS USE MAY BE MULTIPLIED. THE SIZE OF THE MATERIAL CAN BE EASILY AND QUICKLY CHANGED, SHAPES CAN BE…

  6. Overhead Projector Demonstrations.

    ERIC Educational Resources Information Center

    Hambly, Gordon F.; Goldsmith, Robert H.

    1988-01-01

    Presented is a method of demonstrating the optical activity of glucose using an overhead projector and easily obtainable materials. Explores the difference between reflected and transmitted light (Tyndall Effect) using sodium thiosulfate, hydrochloric acid, and an overhead projector. (ML)

  7. Overhead Projector Demonstrations.

    ERIC Educational Resources Information Center

    Kolb, Doris, Ed.

    1989-01-01

    Described are two demonstrations for teaching chemistry using the overhead projector. Included are "Oxidation of Cyclohexanol--An Amoebalike Reaction," and "A Diels-Alder Reaction for the Overhead Projector." Materials and procedures are detailed. (CW)

  8. Overhead Projector Demonstrations.

    ERIC Educational Resources Information Center

    Hambly, Gordon F.; Goldsmith, Robert H.

    1988-01-01

    Presented is a method of demonstrating the optical activity of glucose using an overhead projector and easily obtainable materials. Explores the difference between reflected and transmitted light (Tyndall Effect) using sodium thiosulfate, hydrochloric acid, and an overhead projector. (ML)

  9. Overhead Image Statistics

    SciTech Connect

    Vijayaraj, Veeraraghavan; Cheriyadat, Anil M; Bhaduri, Budhendra L; Vatsavai, Raju; Bright, Eddie A

    2008-01-01

    Statistical properties of high-resolution overhead images representing different land use categories are analyzed using various local and global statistical image properties based on the shape of the power spectrum, image gradient distributions, edge co-occurrence, and inter-scale wavelet coefficient distributions. The analysis was performed on a database of high-resolution (1 meter) overhead images representing a multitude of different downtown, suburban, commercial, agricultural and wooded exemplars. Various statistical properties relating to these image categories and their relationship are discussed. The categorical variations in power spectrum contour shapes, the unique gradient distribution characteristics of wooded categories, the similarity in edge co-occurrence statistics for overhead and natural images, and the unique edge co-occurrence statistics of downtown categories are presented in this work. Though previous work on natural image statistics has showed some of the unique characteristics for different categories, the relationships for overhead images are not well understood. The statistical properties of natural images were used in previous studies to develop prior image models, to predict and index objects in a scene and to improve computer vision models. The results from our research findings can be used to augment and adapt computer vision algorithms that rely on prior image statistics to process overhead images, calibrate the performance of overhead image analysis algorithms, and derive features for better discrimination of overhead image categories.

  10. Overhead Projector Demonstrations.

    ERIC Educational Resources Information Center

    Kolb, Doris, Ed.

    1987-01-01

    Describes several chemistry demonstrations that use an overhead projector. Some of the demonstrations deal with electrochemistry, and another deals with the reactions of nonvolatile immiscible liquid in water. (TW)

  11. Anania Shirakatsi's Overheads System

    NASA Astrophysics Data System (ADS)

    Eynatyan, Julieta

    2014-10-01

    A review of Anania Shirakatsi's overheads system is given based on his chronological works. Lunar, solar and lunisolar calendars are discussed. Anania Shirakatsi is presented as having an important role in the establishment of the Armenian unique chronology.

  12. Overhead Projector Demonstrations.

    ERIC Educational Resources Information Center

    Kolb, Doris, Ed.

    1989-01-01

    Described are demonstrations of the optical activity of two sugar solutions, and the effects of various substituents on acid strength using an overhead projector. Materials and procedures for each demonstration are discussed. (CW)

  13. Kv5, Kv6, Kv8, and Kv9 subunits: No simple silent bystanders

    PubMed Central

    2016-01-01

    Members of the electrically silent voltage-gated K+ (Kv) subfamilies (Kv5, Kv6, Kv8, and Kv9, collectively identified as electrically silent voltage-gated K+ channel [KvS] subunits) do not form functional homotetrameric channels but assemble with Kv2 subunits into heterotetrameric Kv2/KvS channels with unique biophysical properties. Unlike the ubiquitously expressed Kv2 subunits, KvS subunits show a more restricted expression. This raises the possibility that Kv2/KvS heterotetramers have tissue-specific functions, making them potential targets for the development of novel therapeutic strategies. Here, I provide an overview of the expression of KvS subunits in different tissues and discuss their proposed role in various physiological and pathophysiological processes. This overview demonstrates the importance of KvS subunits and Kv2/KvS heterotetramers in vivo and the importance of considering KvS subunits and Kv2/KvS heterotetramers in the development of novel treatments. PMID:26755771

  14. Overhead Projector Demonstrations.

    ERIC Educational Resources Information Center

    Kolb, Doris, Ed.

    1988-01-01

    Details two demonstrations for use with an overhead projector in a chemistry lecture. Includes "A Very Rapidly Growing Silicate Crystal" and "A Colorful Demonstration to Simulate Orbital Hybridization." The materials and directions for each demonstration are included as well as a brief explanation of the essential learning involved. (CW)

  15. 15. INTERIOR, INSPECTION PITS, OVERHEAD CATWALKS AND OVERHEAD CRANE SUPPORT, ...

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

    15. INTERIOR, INSPECTION PITS, OVERHEAD CATWALKS AND OVERHEAD CRANE SUPPORT, FACING WEST - Delaware, Lackawanna & Western Railroad Freight & Rail Yard, Multiple Unit Light Inspection Shed, New Jersey Transit Hoboken Terminal Rail Yard, Hoboken, Hudson County, NJ

  16. Manipulator system for constructing overhead distribution lines

    SciTech Connect

    Ohnishi, H.; Tsuchihashi, H.; Waki, S.; Mochizuki, K. ); Yamamoto, T.; Watanabe, H. ); Furukawa, H. )

    1993-04-01

    This paper describes the manipulator for live-line construction of high-voltage overhead power transmission lines (line voltage 6.6 kV) that is being jointly developed by Tokyo Electric Power and other companies. It describes this system's development concept, makeup, functions, and design, as well as operability tests using actual-scale transmission line poles. In this research, development began in 1984. As the first step, a prototype model of a ground-mounted twin-arm manipulator was trial-manufactured in 1985. As the second step, in 1988 a truck-mounted system was developed in which the twin-arm manipulator was mounted on a cherrypicker vehicle. As the third step, a practical system was developed based on these results.

  17. Overhead camshaft engine

    SciTech Connect

    Honma, M.

    1987-07-21

    This patent describes an overhead camshaft engine comprising: a cylinder block; a cylinder head; a fastening member for fastening the cylinder head to the cylinder block; a valve reciprocally mounted in the cylinder head; and a camshaft rotatably mounted over the cylinder head to control reciprocation of the valve; the camshaft being so arranged, with respect to a plan view, as to lap in part over the fastening member and formed with a peripheral cut at a portion where it laps over the fastening member to facilitate insertion and removal of the fastening member.

  18. Overhead-valve engine

    SciTech Connect

    Tamba, S.; Miyake, H.; Fukui, N.

    1987-05-05

    An overhead valve engine is described comprising: push rod receiving bores, at least one of the push rod receiving bores being maintained in communication at one end with a crank chamber and at an opposite end with a rocker arm chamber and at least one other push rod receiving bore being maintained in communication with the rocker arm chamber; push rods contained within push rod receiving bores; and a breather chamber in communication with at least one other push rod receiving bore in the vicinity of a camshaft.

  19. Electrical and mechanical design criteria for EHV and UHV: overhead transmission lines

    SciTech Connect

    Not Available

    1980-06-01

    The results are presented of a program devoted to the selection of electrical and mechanical design criteria and parameters for overhead power transmission lines for ac systems rated at from 345 to 1100 kV and for dc systems rated at from 600 to 1200 kV. Information is included on the environmental effects, i.e., audible noise and electric fields, of the lines, mechanical and economic requirements, safety, failures, grounding, and lightning protection. (LCL)

  20. First structure on MoronytoRainbow 100kV Transmission Line below Morony Dam ...

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

    First structure on Morony-to-Rainbow 100kV Transmission Line below Morony Dam and Power House. Three-pole H-frame structure with historic porcelain suspension insulators, jumper supports insulators, overhead ground wires, and pole stubs. View to east-northeast - Morony Hydroelectric Facility, Morony-to-Rainbow 100 kV Transmission Line, West bank of the Missouri River, Great Falls, Cascade County, MT

  1. Measurement of SIFT operating system overhead

    NASA Technical Reports Server (NTRS)

    Palumbo, D. L.; Butler, R. W.

    1985-01-01

    The overhead of the software implemented fault tolerance (SIFT) operating system was measured. Several versions of the operating system evolved. Each version represents different strategies employed to improve the measured performance. Three of these versions are analyzed. The internal data structures of the operating systems are discussed. The overhead of the SIFT operating system was found to be of two types: vote overhead and executive task overhead. Both types of overhead were found to be significant in all versions of the system. Improvements substantially reduced this overhead; even with these improvements, the operating system consumed well over 50% of the available processing time.

  2. Spectroscopy on the Overhead Projector.

    ERIC Educational Resources Information Center

    Solomon, Sally; And Others

    1994-01-01

    Any overhead projector easily can be converted into a simple spectrometer by placing a piece of diffraction grating over the projecting lens. A detailed description of the apparatus and suggested spectroscopy experiments are included. Demonstrations can utilize solutions of cobalt chloride, potassium permanganate, potassium dichromate, or…

  3. Creating Great Overheads with Computers.

    ERIC Educational Resources Information Center

    Gribas, Cyndy; And Others

    1996-01-01

    Steps in preparing effective overhead projector transparencies for college instruction are outlined, using the PowerPoint program for Windows. They include thinking analogically in translating from concept to visual form; using the features of the presentation program to create a polished product; and assuring readability (visibility, typeface…

  4. Spectroscopy on the Overhead Projector.

    ERIC Educational Resources Information Center

    Solomon, Sally; And Others

    1994-01-01

    Any overhead projector easily can be converted into a simple spectrometer by placing a piece of diffraction grating over the projecting lens. A detailed description of the apparatus and suggested spectroscopy experiments are included. Demonstrations can utilize solutions of cobalt chloride, potassium permanganate, potassium dichromate, or…

  5. Creating Great Overheads with Computers.

    ERIC Educational Resources Information Center

    Gribas, Cyndy; And Others

    1996-01-01

    Steps in preparing effective overhead projector transparencies for college instruction are outlined, using the PowerPoint program for Windows. They include thinking analogically in translating from concept to visual form; using the features of the presentation program to create a polished product; and assuring readability (visibility, typeface…

  6. Remote Overhead Video Extendable Robot

    SciTech Connect

    Heckendorn, F.M.; Ward, C.R.

    1989-01-01

    The Savannah River Plant (SRP) production of nuclear materials utilizes a waste storage farm, for radioactive waste products. The operation of the waste farm requires manipulation of piping and vessels within below ground pump pits, by overhead crane. A resultant potential exists for personnel exposure to radiation when any direct viewing is used to control crane operations. The Savannah River Laboratory (SRL) has developed a Remote Overhead Video Extendable Robot (ROVER) as a means of reducing the exposure of personnel to nuclear radiation in the waste storage farm. ROVER has been developed, and turned over to the plant area for usage over the pump pits. All operation and control of ROVER are from a remotely located Video Van, located well away from the potentially hazardous operations. 4 figs.

  7. Quantum compiling with low overhead

    NASA Astrophysics Data System (ADS)

    Duclos-Cianci, Guillaume; Poulin, David

    2014-03-01

    I will present a scheme to compile complex quantum gates that uses significantly fewer resources than existing schemes. In standard fault-tolerant protocols, a magic state is distilled from noisy resources, and copies of this magic state are then assembled into produced complex gates using the Solovay-Kitaev theorem or variants thereof. In our approach, we instead directly distill magic states associated to complex gates from noisy resources, leading to a reduction of the compiling overhead of several orders of magnitude.

  8. Proximal Biceps in Overhead Athletes.

    PubMed

    Chalmers, Peter N; Verma, Nikhil N

    2016-01-01

    The proximal long head of the biceps tendon and its attachment at the superior glenoid tubercle and labrum are subject to a spectrum of disorders in overhead athletes. Biceps disorders are commonly characterized by intermittent anterior or deep-seated shoulder pain exacerbated by activity. Diagnosis is reached via various physical examination maneuvers; MRI can be uncertain. Nonsteroidal anti-inflammatory medications, targeted ultrasound-guided corticosteroid injections, and supervised physical therapy are the mainstays of nonoperative treatment. Operative treatment, which remains controversial, provides reliable pain relief, restoration of function for activities of daily living, and low complication rates, but return to play can be unpredictable.

  9. 30 CFR 1220.012 - Overhead allowance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... OIL AND GAS LEASES § 1220.012 Overhead allowance. (a) During the capital recovery period the overhead... allocable joint costs charged to the NPSL capital account, exclusive of costs specified in paragraph (c) of... joint costs charged to the NPSL capital account, exclusive of costs specified in paragraph (c) of this...

  10. Overhead tray for cable test system

    NASA Technical Reports Server (NTRS)

    Saltz, K. T.

    1976-01-01

    System consists of overhead slotted tray, series of compatible adapter cables, and automatic test set which consists of control console and cable-switching console. System reduces hookup time and also reduces cost of fabricating and storing test cables.

  11. Overhead Door Company of Charleston Information Sheet

    EPA Pesticide Factsheets

    Overhead Door Company of Charleston (the Company) is located in North Charleston, South Carolina. The settlement involves renovation activities conducted at a property constructed prior to 1978, located in Isle of Palms, South Carolina.

  12. Mechanosensitive gating of Kv channels.

    PubMed

    Morris, Catherine E; Prikryl, Emil A; Joós, Béla

    2015-01-01

    K-selective voltage-gated channels (Kv) are multi-conformation bilayer-embedded proteins whose mechanosensitive (MS) Popen(V) implies that at least one conformational transition requires the restructuring of the channel-bilayer interface. Unlike Morris and colleagues, who attributed MS-Kv responses to a cooperative V-dependent closed-closed expansion↔compaction transition near the open state, Mackinnon and colleagues invoke expansion during a V-independent closed↔open transition. With increasing membrane tension, they suggest, the closed↔open equilibrium constant, L, can increase >100-fold, thereby taking steady-state Popen from 0→1; "exquisite sensitivity to small…mechanical perturbations", they state, makes a Kv "as much a mechanosensitive…as…a voltage-dependent channel". Devised to explain successive gK(V) curves in excised patches where tension spontaneously increased until lysis, their L-based model falters in part because of an overlooked IK feature; with recovery from slow inactivation factored in, their g(V) datasets are fully explained by the earlier model (a MS V-dependent closed-closed transition, invariant L≥4). An L-based MS-Kv predicts neither known Kv time courses nor the distinctive MS responses of Kv-ILT. It predicts Kv densities (hence gating charge per V-sensor) several-fold different from established values. If opening depended on elevated tension (L-based model), standard gK(V) operation would be compromised by animal cells' membrane flaccidity. A MS V-dependent transition is, by contrast, unproblematic on all counts. Since these issues bear directly on recent findings that mechanically-modulated Kv channels subtly tune pain-related excitability in peripheral mechanoreceptor neurons we undertook excitability modeling (evoked action potentials). Kvs with MS V-dependent closed-closed transitions produce nuanced mechanically-modulated excitability whereas an L-based MS-Kv yields extreme, possibly excessive (physiologically

  13. Overhead-Aware-Best-Fit (OABF) Resource Allocation Algorithm for Minimizing VM Launching Overhead

    SciTech Connect

    Wu, Hao; Garzoglio, Gabriele; Ren, Shangping; Timm, Steven; Noh, Seo Young

    2014-11-11

    FermiCloud is a private cloud developed in Fermi National Accelerator Laboratory to provide elastic and on-demand resources for different scientific research experiments. The design goal of the FermiCloud is to automatically allocate resources for different scientific applications so that the QoS required by these applications is met and the operational cost of the FermiCloud is minimized. Our earlier research shows that VM launching overhead has large variations. If such variations are not taken into consideration when making resource allocation decisions, it may lead to poor performance and resource waste. In this paper, we show how we may use an VM launching overhead reference model to minimize VM launching overhead. In particular, we first present a training algorithm that automatically tunes a given refer- ence model to accurately reflect FermiCloud environment. Based on the tuned reference model for virtual machine launching overhead, we develop an overhead-aware-best-fit resource allocation algorithm that decides where and when to allocate resources so that the average virtual machine launching overhead is minimized. The experimental results indicate that the developed overhead-aware-best-fit resource allocation algorithm can significantly improved the VM launching time when large number of VMs are simultaneously launched.

  14. 30 CFR 56.12045 - Overhead powerlines.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Overhead powerlines. 56.12045 Section 56.12045 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity §...

  15. 30 CFR 56.12045 - Overhead powerlines.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Overhead powerlines. 56.12045 Section 56.12045 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity §...

  16. 30 CFR 56.12045 - Overhead powerlines.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Overhead powerlines. 56.12045 Section 56.12045 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity §...

  17. 30 CFR 56.12045 - Overhead powerlines.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Overhead powerlines. 56.12045 Section 56.12045 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity §...

  18. 30 CFR 56.12045 - Overhead powerlines.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Overhead powerlines. 56.12045 Section 56.12045 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity §...

  19. The Overhead Projector in the Mathematics Classroom.

    ERIC Educational Resources Information Center

    Lenchner, George

    The first section of this pamphlet illustrates and describes the overhead projector, and discusses several of its advantages over other projection devises, including its simplicity of operation, conservation of class time, dynamic effects, image size, etc. The second section describes in some detail materials and methods used to make visuals, then…

  20. 29 CFR 1926.955 - Overhead lines.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Power Transmission and Distribution § 1926.955 Overhead... event of high wind or other adverse weather conditions which would make the work hazardous. (v... procedures, work from structures shall be discontinued when adverse weather (such as high wind or ice...

  1. 29 CFR 1926.955 - Overhead lines.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Power Transmission and Distribution § 1926.955 Overhead... event of high wind or other adverse weather conditions which would make the work hazardous. (v... procedures, work from structures shall be discontinued when adverse weather (such as high wind or ice...

  2. Viewing Vertical Objects with an Overhead Projector.

    ERIC Educational Resources Information Center

    Wild, R. L.

    1988-01-01

    Discusses the use of an overhead projector for the deflection of a vertical image to a screen. Describes three demonstrations: magnetizing of a steel ball bearing and paper clip; convection currents of a hot liquid within a cold liquid; and oscillation of concentrated salt solution into fresh water. (YP)

  3. The Overhead Projector in the Mathematics Classroom.

    ERIC Educational Resources Information Center

    Lenchner, George

    The first section of this pamphlet illustrates and describes the overhead projector, and discusses several of its advantages over other projection devises, including its simplicity of operation, conservation of class time, dynamic effects, image size, etc. The second section describes in some detail materials and methods used to make visuals, then…

  4. Centripetal Force on an Overhead Projector.

    ERIC Educational Resources Information Center

    Rheam, Harry

    1995-01-01

    Describes two simple demonstrations of an object moving in a straight line tangent to the circle if centripetal force is removed. Demonstrations use a pie plate and petri dish with ball bearings to illustrate the phenomena on an overhead projector. (LZ)

  5. Viewing Vertical Objects with an Overhead Projector.

    ERIC Educational Resources Information Center

    Wild, R. L.

    1988-01-01

    Discusses the use of an overhead projector for the deflection of a vertical image to a screen. Describes three demonstrations: magnetizing of a steel ball bearing and paper clip; convection currents of a hot liquid within a cold liquid; and oscillation of concentrated salt solution into fresh water. (YP)

  6. Centripetal Force on an Overhead Projector.

    ERIC Educational Resources Information Center

    Rheam, Harry

    1995-01-01

    Describes two simple demonstrations of an object moving in a straight line tangent to the circle if centripetal force is removed. Demonstrations use a pie plate and petri dish with ball bearings to illustrate the phenomena on an overhead projector. (LZ)

  7. Overhead Projection Cell for Streamline Flow

    ERIC Educational Resources Information Center

    Waage, Harold M.

    1969-01-01

    Describes the construction and operation of an overhead projection apparatus designed to demonstrate streamline flow of a liquid. The apparatus consists of a Plexiglass tank containing water in which plates forming the cell are submerged, a constant level reservoir, an overflow device and a system for marking the flow lines with a dye. (LC)

  8. Kv7 and Kv11 channels in myometrial regulation

    PubMed Central

    Greenwood, Iain A; Tribe, Rachel M

    2014-01-01

    Ion channels play a key role in defining myometrial contractility. Modulation of ion channel populations is proposed to underpin gestational changes in uterine contractility associated with the transition from uterine quiescence to active labour. Of the myriad ion channels present in the uterus, this article will focus upon potassium channels encoded by the KCNQ genes and ether-à-go-go-related (ERG) genes. Voltage-gated potassium channels encoded by KCNQ and ERG (termed Kv7 and Kv11, respectively) are accepted as major determinants of neuronal excitability and the duration of the cardiac action potential. However, there is now growing appreciation that these ion channels have a major functional impact in vascular and non-vascular smooth muscle. Moreover, Kv7 channels may be potential therapeutic targets for the treatment of preterm labour. PMID:24121285

  9. Mechanosensitive Gating of Kv Channels

    PubMed Central

    Morris, Catherine E.; Prikryl, Emil A.; Joós, Béla

    2015-01-01

    K-selective voltage-gated channels (Kv) are multi-conformation bilayer-embedded proteins whose mechanosensitive (MS) Popen(V) implies that at least one conformational transition requires the restructuring of the channel-bilayer interface. Unlike Morris and colleagues, who attributed MS-Kv responses to a cooperative V-dependent closed-closed expansion↔compaction transition near the open state, Mackinnon and colleagues invoke expansion during a V-independent closed↔open transition. With increasing membrane tension, they suggest, the closed↔open equilibrium constant, L, can increase >100-fold, thereby taking steady-state Popen from 0→1; “exquisite sensitivity to small…mechanical perturbations”, they state, makes a Kv “as much a mechanosensitive…as…a voltage-dependent channel”. Devised to explain successive gK(V) curves in excised patches where tension spontaneously increased until lysis, their L-based model falters in part because of an overlooked IK feature; with recovery from slow inactivation factored in, their g(V) datasets are fully explained by the earlier model (a MS V-dependent closed-closed transition, invariant L≥4). An L-based MS-Kv predicts neither known Kv time courses nor the distinctive MS responses of Kv-ILT. It predicts Kv densities (hence gating charge per V-sensor) several-fold different from established values. If opening depended on elevated tension (L-based model), standard gK(V) operation would be compromised by animal cells’ membrane flaccidity. A MS V-dependent transition is, by contrast, unproblematic on all counts. Since these issues bear directly on recent findings that mechanically-modulated Kv channels subtly tune pain-related excitability in peripheral mechanoreceptor neurons we undertook excitability modeling (evoked action potentials). Kvs with MS V-dependent closed-closed transitions produce nuanced mechanically-modulated excitability whereas an L-based MS-Kv yields extreme, possibly excessive

  10. 29 CFR 1926.1438 - Overhead & gantry cranes.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 8 2013-07-01 2013-07-01 false Overhead & gantry cranes. 1926.1438 Section 1926.1438 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Cranes and Derricks in Construction § 1926.1438 Overhead & gantry cranes. (a) Permanently installed overhead and gantry cranes. The requirements of § 1910...

  11. 30 CFR 56.16014 - Operator-carrying overhead cranes.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Operator-carrying overhead cranes. 56.16014 Section 56.16014 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Storage and Handling § 56.16014 Operator-carrying overhead cranes. Operator-carrying overhead cranes shall...

  12. 30 CFR 56.16014 - Operator-carrying overhead cranes.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Operator-carrying overhead cranes. 56.16014 Section 56.16014 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Storage and Handling § 56.16014 Operator-carrying overhead cranes. Operator-carrying overhead cranes shall...

  13. 29 CFR 1926.1438 - Overhead & gantry cranes.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 8 2014-07-01 2014-07-01 false Overhead & gantry cranes. 1926.1438 Section 1926.1438 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Cranes and Derricks in Construction § 1926.1438 Overhead & gantry cranes. (a) Permanently installed overhead and gantry cranes. The requirements of § 1910...

  14. 30 CFR 57.16014 - Operator-carrying overhead cranes.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Operator-carrying overhead cranes. 57.16014 Section 57.16014 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Storage and Handling § 57.16014 Operator-carrying overhead cranes. Operator-carrying overhead cranes shall...

  15. 30 CFR 57.16014 - Operator-carrying overhead cranes.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Operator-carrying overhead cranes. 57.16014 Section 57.16014 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Storage and Handling § 57.16014 Operator-carrying overhead cranes. Operator-carrying overhead cranes shall...

  16. 30 CFR 57.16014 - Operator-carrying overhead cranes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Operator-carrying overhead cranes. 57.16014 Section 57.16014 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Storage and Handling § 57.16014 Operator-carrying overhead cranes. Operator-carrying overhead cranes shall...

  17. 30 CFR 57.16014 - Operator-carrying overhead cranes.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Operator-carrying overhead cranes. 57.16014 Section 57.16014 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Storage and Handling § 57.16014 Operator-carrying overhead cranes. Operator-carrying overhead cranes shall...

  18. 30 CFR 56.16014 - Operator-carrying overhead cranes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Operator-carrying overhead cranes. 56.16014 Section 56.16014 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Storage and Handling § 56.16014 Operator-carrying overhead cranes. Operator-carrying overhead cranes shall...

  19. 30 CFR 57.16014 - Operator-carrying overhead cranes.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Operator-carrying overhead cranes. 57.16014 Section 57.16014 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Storage and Handling § 57.16014 Operator-carrying overhead cranes. Operator-carrying overhead cranes shall...

  20. 29 CFR 1926.1438 - Overhead & gantry cranes.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 8 2012-07-01 2012-07-01 false Overhead & gantry cranes. 1926.1438 Section 1926.1438 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Cranes and Derricks in Construction § 1926.1438 Overhead & gantry cranes. (a) Permanently installed overhead and gantry cranes. The requirements of § 1910...

  1. 30 CFR 56.16014 - Operator-carrying overhead cranes.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Operator-carrying overhead cranes. 56.16014 Section 56.16014 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Storage and Handling § 56.16014 Operator-carrying overhead cranes. Operator-carrying overhead cranes shall...

  2. 30 CFR 56.16014 - Operator-carrying overhead cranes.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Operator-carrying overhead cranes. 56.16014 Section 56.16014 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Storage and Handling § 56.16014 Operator-carrying overhead cranes. Operator-carrying overhead cranes shall...

  3. 19 CFR 24.21 - Administrative overhead charges.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... THE TREASURY CUSTOMS FINANCIAL AND ACCOUNTING PROCEDURE § 24.21 Administrative overhead charges. (a) Reimbursable and overtime services. An additional charge for administrative overhead costs shall be collected....17 and 24.16, respectively, of this part. The cost of the charge for administrative overhead shall be...

  4. 23 CFR 140.907 - Overhead and indirect construction costs.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... which assure proper control and distribution of the overhead and indirect construction costs. ... 23 Highways 1 2012-04-01 2012-04-01 false Overhead and indirect construction costs. 140.907... REIMBURSEMENT Reimbursement for Railroad Work § 140.907 Overhead and indirect construction costs. (a) A...

  5. 30 CFR 56.14108 - Overhead drive belts.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Overhead drive belts. 56.14108 Section 56.14108 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Safety Devices and Maintenance Requirements § 56.14108 Overhead drive belts. Overhead drive belts...

  6. 30 CFR 57.14108 - Overhead drive belts.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Overhead drive belts. 57.14108 Section 57.14108 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Equipment Safety Devices and Maintenance Requirements § 57.14108 Overhead drive belts. Overhead drive...

  7. 30 CFR 56.14108 - Overhead drive belts.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Overhead drive belts. 56.14108 Section 56.14108 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Safety Devices and Maintenance Requirements § 56.14108 Overhead drive belts. Overhead drive belts...

  8. 30 CFR 56.14108 - Overhead drive belts.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Overhead drive belts. 56.14108 Section 56.14108 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Safety Devices and Maintenance Requirements § 56.14108 Overhead drive belts. Overhead drive belts...

  9. 30 CFR 57.14108 - Overhead drive belts.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Overhead drive belts. 57.14108 Section 57.14108 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Equipment Safety Devices and Maintenance Requirements § 57.14108 Overhead drive belts. Overhead drive...

  10. 30 CFR 56.14108 - Overhead drive belts.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Overhead drive belts. 56.14108 Section 56.14108 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Safety Devices and Maintenance Requirements § 56.14108 Overhead drive belts. Overhead drive belts...

  11. 30 CFR 57.14108 - Overhead drive belts.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Overhead drive belts. 57.14108 Section 57.14108 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Equipment Safety Devices and Maintenance Requirements § 57.14108 Overhead drive belts. Overhead drive...

  12. 30 CFR 57.14108 - Overhead drive belts.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Overhead drive belts. 57.14108 Section 57.14108 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Equipment Safety Devices and Maintenance Requirements § 57.14108 Overhead drive belts. Overhead drive...

  13. 30 CFR 57.14108 - Overhead drive belts.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Overhead drive belts. 57.14108 Section 57.14108 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Equipment Safety Devices and Maintenance Requirements § 57.14108 Overhead drive belts. Overhead drive...

  14. 30 CFR 56.14108 - Overhead drive belts.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Overhead drive belts. 56.14108 Section 56.14108 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Safety Devices and Maintenance Requirements § 56.14108 Overhead drive belts. Overhead drive belts...

  15. A new method for overhead drilling.

    PubMed

    Rempel, David; Star, Demetra; Barr, Alan; Gibbons, Billy; Janowitz, Ira

    2009-12-01

    In the construction sector, overhead drilling into concrete or metal ceilings is a strenuous task associated with shoulder, neck and back musculoskeletal disorders due to the large applied forces and awkward arm postures. Two intervention devices, an inverted drill press and a foot lever design, were developed then compared to the usual method by construction workers performing their normal overhead drilling activities (n = 14). While the intervention devices were rated as less fatiguing than the usual method, their ratings on usability measures were worse than the usual method. The study demonstrates that the intervention devices can reduce fatigue; however, additional modifications are necessary in order to improve usability and productivity. Devices designed to improve workplace safety may need to undergo several rounds of field testing and modification prior to implementation.

  16. Shoulder Injuries in the Overhead Throwing Athlete.

    PubMed

    Mlynarek, Ryan A; Lee, Simon; Bedi, Asheesh

    2017-02-01

    The overhead pitching motion is a coordinated sequence of movements that subjects the shoulder to extreme forces. The ultimate goal of this complex, dynamic activity is to generate high ball velocity and accuracy. In doing so, repetitive throwing can cause adaptive and pathologic changes in the thrower's shoulder. This article reviews the relevant shoulder anatomy, the kinetic chain, and throwing mechanics, as well as common shoulder injuries and surgical options for the treating orthopedic surgeon.

  17. Human Factors Engineering Guidelines for Overhead Cranes

    NASA Technical Reports Server (NTRS)

    Chandler, Faith; Delgado, H. (Technical Monitor)

    2001-01-01

    This guideline provides standards for overhead crane cabs that can be applied to the design and modification of crane cabs to reduce the potential for human error due to design. This guideline serves as an aid during the development of a specification for purchases of cranes or for an engineering support request for crane design modification. It aids human factors engineers in evaluating existing cranes during accident investigations or safety reviews.

  18. Predictive model of avian electrocution risk on overhead power lines.

    PubMed

    Dwyer, J F; Harness, R E; Donohue, K

    2014-02-01

    Electrocution on overhead power structures negatively affects avian populations in diverse ecosystems worldwide, contributes to the endangerment of raptor populations in Europe and Africa, and is a major driver of legal action against electric utilities in North America. We investigated factors associated with avian electrocutions so poles that are likely to electrocute a bird can be identified and retrofitted prior to causing avian mortality. We used historical data from southern California to identify patterns of avian electrocution by voltage, month, and year to identify species most often killed by electrocution in our study area and to develop a predictive model that compared poles where an avian electrocution was known to have occurred (electrocution poles) with poles where no known electrocution occurred (comparison poles). We chose variables that could be quantified by personnel with little training in ornithology or electric systems. Electrocutions were more common at distribution voltages (≤ 33 kV) and during breeding seasons and were more commonly reported after a retrofitting program began. Red-tailed Hawks (Buteo jamaicensis) (n = 265) and American Crows (Corvus brachyrhynchos) (n = 258) were the most commonly electrocuted species. In the predictive model, 4 of 14 candidate variables were required to distinguish electrocution poles from comparison poles: number of jumpers (short wires connecting energized equipment), number of primary conductors, presence of grounding, and presence of unforested unpaved areas as the dominant nearby land cover. When tested against a sample of poles not used to build the model, our model distributed poles relatively normally across electrocution-risk values and identified the average risk as higher for electrocution poles relative to comparison poles. Our model can be used to reduce avian electrocutions through proactive identification and targeting of high-risk poles for retrofitting. © 2013 Society for Conservation

  19. Kv1.3/Kv1.5 heteromeric channels compromise pharmacological responses in macrophages

    SciTech Connect

    Villalonga, Nuria; Escalada, Artur; Vicente, Ruben; Sanchez-Tillo, Ester; Celada, Antonio; Solsona, Carles; Felipe, Antonio . E-mail: afelipe@ub.edu

    2007-01-26

    Voltage-dependent K{sup +} (Kv) channels are involved in the immune response. Kv1.3 is highly expressed in activated macrophages and T-effector memory cells of autoimmune disease patients. Macrophages are actively involved in T-cell activation by cytokine production and antigen presentation. However, unlike T-cells, macrophages express Kv1.5, which is resistant to Kv1.3-drugs. We demonstrate that mononuclear phagocytes express different Kv1.3/Kv1.5 ratios, leading to biophysically and pharmacologically distinct channels. Therefore, Kv1.3-based treatments to alter physiological responses, such as proliferation and activation, are impaired by Kv1.5 expression. The presence of Kv1.5 in the macrophagic lineage should be taken into account when designing Kv1.3-based therapies.

  20. Claims for Unabsorbed Overhead on Defense Contracts.

    DTIC Science & Technology

    1985-09-01

    increase overhead costs" (7:20). In a concurring opinion, Administrative Judge Lieblich makes a couple of points very clear: (1) as far as this Board is...method of calculating these coats C7:13. Judge Lieblich than goes on to qualify his seemingly strong words about the "Eichleay" formula. He states...BCA, 83-2: 1-32 and (1-2 of Concurring opinio-f Judge Lieblich ) (17 February 1983). 8. Capital Electric co. vs. The United States, No. 83-965, CAFC: 1

  1. Sidney-North Yuma 230-kV Transmission Line Project, Colorado and Nebraska

    SciTech Connect

    Not Available

    1991-06-01

    This report describes the need for a 230-kV overhead transmission line to supply power from Sidney, Nebraska to eastern Colorado. The alternative scenario compared to construction of the line is No Action. Rejected alternatives include underground lines and different routing paths, with a possible extension to the Sterling area. Both scenarios are evaluated for environmental effects, cost, and consequences for the eastern Colorado region. The proposed route is determined to be the environmentally preferred choice. 120 refs., 6 figs., 13 tabs. (MHB)

  2. Shoulder Pain in the Overhead Throwing Athlete

    PubMed Central

    Seroyer, Shane T.; Nho, Shane J.; Bach, Bernard R.; Bush-Joseph, Charles A.; Nicholson, Gregory P.; Romeo, Anthony A.

    2009-01-01

    Treatment of the overhead throwing athlete is among the more challenging aspects of orthopaedic sports medicine. Awareness and understanding of the throwing motion and the supraphysiologic forces to which the structures of the shoulder are subjected are essential to diagnosis and treatment. Pain and dysfunction in the throwing shoulder may be attributed to numerous etiologies, including scapular dysfunction, intrinsic glenohumeral pathology (capsulolabral structures), extrinsic musculature (rotator cuff), or neurovascular structures. Attention to throwing mechanics and appropriate stretching, strength, and conditioning programs may reduce the risk of injury in this highly demanding activity. Early discovery of symptoms, followed by conservative management with rest and rehabilitation with special attention to retraining mechanics may mitigate the need for surgical intervention. Prevention of injury is always more beneficial to the long-term health of the thrower than is surgical repair. An anatomic approach is used in this report, focusing on common etiologies of pain in the overhead thrower and emphasizing the clinical presentation and treatment. PMID:23015861

  3. Troubleshooting crude vacuum tower overhead ejector systems

    SciTech Connect

    Lines, J.R.; Frens, L.L. )

    1995-03-01

    Routinely surveying tower overhead vacuum systems can improve performance and product quality. These vacuum systems normally provide reliable and consistent operation. However, process conditions, supplied utilities, corrosion, erosion and fouling all have an impact on ejector system performance. Refinery vacuum distillation towers use ejector systems to maintain tower top pressure and remove overhead gases. However, as with virtually all refinery equipment, performance may be affected by a number of variables. These variables may act independently or concurrently. It is important to understand basic operating principles of vacuum systems and how performance is affected by: utilities, corrosion and erosion, fouling, and process conditions. Reputable vacuum-system suppliers have service engineers that will come to a refinery to survey the system and troubleshoot performance or offer suggestions for improvement. A skilled vacuum-system engineer may be needed to diagnose and remedy system problems. The affect of these variables on performance is discussed. A case history is described of a vacuum system on a crude tower in a South American refinery.

  4. Overhead analysis of universal concatenated quantum codes

    NASA Astrophysics Data System (ADS)

    Chamberland, Christopher; Jochym-O'Connor, Tomas; Laflamme, Raymond

    2017-02-01

    We analyze the resource overhead of recently proposed methods for universal fault-tolerant quantum computation using concatenated codes. Namely, we examine the concatenation of the 7-qubit Steane code with the 15-qubit Reed-Muller code, which allows for the construction of the 49- and 105-qubit codes that do not require the need for magic state distillation for universality. We compute a lower bound for the adversarial noise threshold of the 105-qubit code and find it to be 8.33 ×10-6. We obtain a depolarizing noise threshold for the 49-qubit code of 9.69 ×10-4 which is competitive with the 105-qubit threshold result of 1.28 ×10-3 . We then provide lower bounds on the resource requirements of the 49- and 105-qubit codes and compare them with the surface code implementation of a logical T gate using magic state distillation. For the sampled input error rates and noise model, we find that the surface code achieves a smaller overhead compared to our concatenated schemes.

  5. Mechanics and pathomechanics in the overhead athlete.

    PubMed

    Kibler, W Ben; Wilkes, Trevor; Sciascia, Aaron

    2013-10-01

    Optimal performance of the overhead throwing task requires precise mechanics that involve coordinated kinetic and kinematic chains to develop, transfer, and regulate the forces the body needs to withstand the inherent demands of the task and to allow optimal performance. These chains have been evaluated and the basic components, called nodes, have been identified. Impaired performance and/or injury, the DTS, is associated with alterations in the mechanics that are called pathomechanics. They can occur at multiple locations throughout the kinetic chain. They must be evaluated and treated as part of the overall problem. Observational analysis of the mechanics and pathomechanics using the node analysis method can be useful in highlighting areas of alteration that can be evaluated for anatomic injury or altered physiology. The comprehensive kinetic chain examination can evaluate sites of kinetic chain breakage, and a detailed shoulder examination can assess joint internal derangement of altered physiology that may contribute to the pathomechanics. Treatment of the DTS should be comprehensive, directed toward restoring physiology and mechanics and optimizing anatomy. This maximizes the body’s ability to develop normal mechanics to accomplish the overhead throwing task.

  6. Conceptual design of 275 kV class high-Tc superconducting cable

    NASA Astrophysics Data System (ADS)

    Mukoyama, S.; Yagi, M.; Fujiwara, N.; Ichikawa, H.

    2010-11-01

    High-temperature superconducting (HTS) cables are expected to be next generation transmission line because of the compact, lightweight, large capacity, and low loss features. Especially, since the YBa2Cu3Ox (YBCO) tape has a high critical current, high magnetic-field property, low AC loss, and low cost, using YBCO tapes for a HTS cable seems to be one of the most promising ways to make the HTS cable attractive. Therefore, YBCO HTS cables have been studied extensively in Japan, the United States, Korea, and many other countries. We now believe that 275 kV class HTS cables will be used for future large capacity lines based on the needs of Japanese transmission networks for bulk transmission power in overhead transmission lines or gas insulated transmission lines (GIL). We started to develop the 275 kV class HTS cable for the new energy and industrial technology development organization (NEDO) project at 2008, and we have studied the applicability and the environmental and economic advantages of the 275 kV cable. This paper will introduce advantages and a conceptual design of the 275 kV HTS cable.

  7. Obstacle negotiation control for a mobile robot suspended on overhead ground wires by optoelectronic sensors

    NASA Astrophysics Data System (ADS)

    Zheng, Li; Yi, Ruan

    2009-11-01

    Power line inspection and maintenance already benefit from developments in mobile robotics. This paper presents mobile robots capable of crossing obstacles on overhead ground wires. A teleoperated robot realizes inspection and maintenance tasks on power transmission line equipment. The inspection robot is driven by 11 motor with two arms, two wheels and two claws. The inspection robot is designed to realize the function of observation, grasp, walk, rolling, turn, rise, and decline. This paper is oriented toward 100% reliable obstacle detection and identification, and sensor fusion to increase the autonomy level. An embedded computer based on PC/104 bus is chosen as the core of control system. Visible light camera and thermal infrared Camera are both installed in a programmable pan-and-tilt camera (PPTC) unit. High-quality visual feedback rapidly becomes crucial for human-in-the-loop control and effective teleoperation. The communication system between the robot and the ground station is based on Mesh wireless networks by 700 MHz bands. An expert system programmed with Visual C++ is developed to implement the automatic control. Optoelectronic laser sensors and laser range scanner were installed in robot for obstacle-navigation control to grasp the overhead ground wires. A novel prototype with careful considerations on mobility was designed to inspect the 500KV power transmission lines. Results of experiments demonstrate that the robot can be applied to execute the navigation and inspection tasks.

  8. 23. OVERALL OVERHEAD VIEW OF MARISCAL WORKS LOOKING NORTH, NORTHEAST. ...

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

    23. OVERALL OVERHEAD VIEW OF MARISCAL WORKS LOOKING NORTH, NORTHEAST. NOTICE REDWOOD TANK PLATFORM LOWER RIGHT FOREGROUND. - Mariscal Quicksilver Mine & Reduction Works, Terlingua, Brewster County, TX

  9. 9. Interior view, overhead line shafting and lathe workbench, east ...

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

    9. Interior view, overhead line shafting and lathe workbench, east shop, ground floor, looking northwest. - Larrabee & Hingston Company, Main Shop Building, 19 Howley Street, Peabody, Essex County, MA

  10. 19. DETAIL, OVERHEAD CATWALK Delaware, Lackawanna & Western Railroad ...

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

    19. DETAIL, OVERHEAD CATWALK - Delaware, Lackawanna & Western Railroad Freight & Rail Yard, Multiple Unit Light Inspection Shed, New Jersey Transit Hoboken Terminal Rail Yard, Hoboken, Hudson County, NJ

  11. Reducing space overhead for independendent checkpointing

    NASA Technical Reports Server (NTRS)

    Wang, Yi-Min; Chung, Pi-Yu; Lin, In-Jen; Fuchs, W. Kent

    1992-01-01

    The main disadvantages of independent checkpointing are the possible domino effect and the associated storage space overhead for maintaining multiple checkpoints. In most previous work, it has been assumed that only the checkpoints older than the current global recovery line can be discarded. Here, we generalize a notion of recovery line to potential recovery line. Only the checkpoints belonging to at least one of the potential recovery lines cannot be discarded. By using the model of maximum-sized antichains on a partially ordered set, an efficient algorithm is developed for finding all non-discardable checkpoints, and we show that the number of non-discardable checkpoints cannot exceed N(N+1)/2, where N is the number of processors. Communication trace driven simulation for several hypercube programs is performed to show the benefit of the proposed algorithm for real applications.

  12. Low-overhead accrual failure detector.

    PubMed

    Ren, Xiao; Dong, Jian; Liu, Hongwei; Li, Yang; Yang, Xiaozong

    2012-01-01

    Failure detectors are one of the fundamental components for building a distributed system with high availability. In order to maintain the efficiency and scalability of failure detection in a complicated large-scale distributed system, accrual failure detectors that can adapt to multiple applications have been studied extensively. In this paper, an new accrual failure detector--LA-FD with low system overhead has been proposed specifically for current mobile network equipment on the Internet whose processing power, memory space and power supply are all constrained. It does not rely on the probability distribution of message transmission time, or on the maintenance of a history message window. By simple calculation, LA-FD provides adaptive failure detection service with high accuracy to multiple upper applications. The related experiments and results have also been presented.

  13. Physical examination of the overhead athlete's shoulder.

    PubMed

    Sewick, Amy; Kelly, John D; Rubin, Ben

    2012-03-01

    Overhead athletes seek the services of an orthopedic surgeon because of pain and/or dysfunction. It is important to address the cause of the symptoms more so than the source of the patient's pain, so that treatment will eliminate the problem rather than merely ameliorate symptoms temporarily. In order to accomplish a thorough assessment of shoulder function, the examiner must expand his/her view from isolated assessment of the glenohumeral joint range of motion, stability, assessment of rotator cuff strength, palpation and provocative maneuvers, and add assessment of the shoulder in the context of the kinetic chain. The examination of the thrower's shoulder, coupled with a thorough history, will usually provide a solid functional diagnosis and provide a good idea as to the presence of structural damage. As a result, the value of rehabilitation and the benefit of surgical intervention are made more predictable.

  14. Geography via the Overhead Projector: Do It This Way, 7.

    ERIC Educational Resources Information Center

    Best, Thomas D.

    This booklet is designed to assist teachers in their use of overhead projectors when teaching geography. With the overhead technique, relationships among patterns can be suggested bit by bit on inexpensive, easily prepared overlays that are projected to sizes appropriate for a particular instructional situation. A general discussion of the…

  15. 1. EAST SIDE OF OVERHEAD BOMB TRANSPORT RACK, WITH BUILDING ...

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

    1. EAST SIDE OF OVERHEAD BOMB TRANSPORT RACK, WITH BUILDING 343 AT LEFT AND BUILDING 328 AT RIGHT. VIEW TO WEST. - Rocky Mountain Arsenal, Overhead Bomb Transport Rack, 1580 feet South of December Seventh Avenue; 860 feet West of D Street, Commerce City, Adams County, CO

  16. 78 FR 77027 - Overhead Clearance (Air-Draft) Accidents

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-20

    ... SECURITY Coast Guard 33 CFR Parts 117, 161, and 164 46 CFR Part 4 Overhead Clearance (Air-Draft) Accidents... address the problem of overhead clearance (air-draft) accidents. In its petition, which calls for vessel masters to be provided with accurate vertical air draft information, a maritime organization has...

  17. Independent movement of the voltage sensors in KV2.1/KV6.4 heterotetramers

    PubMed Central

    Bocksteins, Elke; Snyders, Dirk J.; Holmgren, Miguel

    2017-01-01

    Heterotetramer voltage-gated K+ (KV) channels KV2.1/KV6.4 display a gating charge-voltage (QV) distribution composed by two separate components. We use state dependent chemical accessibility to cysteines substituted in either KV2.1 or KV6.4 to assess the voltage sensor movements of each subunit. By comparing the voltage dependences of chemical modification and gating charge displacement, here we show that each gating charge component corresponds to a specific subunit forming the heterotetramer. The voltage sensors from KV6.4 subunits move at more negative potentials than the voltage sensors belonging to KV2.1 subunits. These results indicate that the voltage sensors from the tetrameric channels move independently. In addition, our data shows that 75% of the total charge is attributed to KV2.1, while 25% to KV6.4. Thus, the most parsimonious model for KV2.1/KV6.4 channels’ stoichiometry is 3:1. PMID:28139741

  18. Big George to Carter Mountain 115-kV transmission line project, Park and Hot Springs Counties, Wyoming. Environmental Assessment

    SciTech Connect

    Not Available

    1994-02-01

    The Western Area Power Administration (Western) is proposing to rebuild, operate, and maintain a 115-kilovolt (kV) transmission line between the Big George and Carter Mountain Substations in northwest Wyoming (Park and Hot Springs Counties). This environmental assessment (EA) was prepared in compliance with the National Environmental Policy Act (NEPA) and the regulations of the Council on Environmental Quality (CEQ) and the Department of Energy (DOE). The existing Big George to Carter Mountain 69-kV transmission line was constructed in 1941 by the US Department of Interior, Bureau of Reclamation, with 1/0 copper conductor on wood-pole H-frame structures without an overhead ground wire. The line should be replaced because of the deteriorated condition of the wood-pole H-frame structures. Because the line lacks an overhead ground wire, it is subject to numerous outages caused by lightning. The line will be 54 years old in 1995, which is the target date for line replacement. The normal service life of a wood-pole line is 45 years. Under the No Action Alternative, no new transmission lines would be built in the project area. The existing 69-kV transmission line would continue to operate with routine maintenance, with no provisions made for replacement.

  19. Overhead View of Pathfinder Landing Site

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Planimetric (overhead view) map of the landing site, to a distance of 20 meters from the spacecraft. North is at the top in this and Plates 3-5. To produce this map, images were geometrically projected onto an assumed mean surface representing the ground. Features above the ground plane (primarily rocks) therefore appear displaced radially outward; the amount of distortion increases systematically with distance. The upper surfaces of the lander and rover also appear enlarged and displaced because of their height. Primary grid (white) is based on the Landing Site Cartographic (LSC) coordinate system, defined with X eastward, Y north, and Z up, and origin located at the mean ground surface immediately beneath the deployed position of the IMP camera gimbal center. Secondary ticks (cyan) are based on the Mars local level (LL) frame, which has X north, Y east, Z down, with origin in the center of the lander baseplate. Rover positions (including APXS measurements) are commonly reported in the LL frame. Yellow grid shows polar coordinates based on the LSC system. Cartographic image processing by U.S. Geological Survey.

    NOTE: original caption as published in Science Magazine

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology (Caltech).

  20. A Study of Electromagnetic Radiation of Corona Discharge Near 500-Kv Electric Installations

    SciTech Connect

    Korzhov, A. V.; Okrainskaya, I. S.; Sidorov, A. I.; Kufel'd, V. D.

    2004-01-15

    Data on the spectral composition and intensity of electromagnetic radiation of corona discharge are obtained in an experimental study performed on the outdoor switchgear of the Shagol 500-kV substation of the Chelyabinsk Enterprise of Trunk Transmission Grids and under a 500-kV Shagol - Kozyrevo overhead transmission line. The electromagnetic environment on the territory of the 500-kV outdoor switchgear is shown to be determined by narrow-band radiations (harmonics of the frequency of electric supply) and wide-band radiations due to corona discharges of high-voltage sources. This means that the personnel experience the action of a commercial-frequency electric field and electromagnetic radiation of a quite wide range, which is not allowed for by the existing guidelines. It is recommended to continue the study in cooperation with medical institutions in order to create guidelines that would allow for the joint action of commercial-frequency electric field and electromagnetic radiation and for the voltage in the line, the current load, the meteorological situation, and other factors.

  1. Overhead View of Area Surrounding Pathfinder

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Overhead view of the area surrounding the Pathfinder lander illustrating the Sojourner traverse. Red rectangles are rover positions at the end of sols 1-30. Locations of soil mechanics experiments, wheel abrasion experiments, and APXS measurements are shown. The A numbers refer to APXS measurements as discussed in the paper by Rieder et al. (p. 1770, Science Magazine, see image note). Coordinates are given in the LL frame.

    The photorealistic, interactive, three-dimensional virtual reality (VR) terrain models were created from IMP images using a software package developed for Pathfinder by C. Stoker et al. as a participating science project. By matching features in the left and right camera, an automated machine vision algorithm produced dense range maps of the nearfield, which were projected into a three-dimensional model as a connected polygonal mesh. Distance and angle measurements can be made on features viewed in the model using a mouse-driven three-dimensional cursor and a point-and-click interface. The VR model also incorporates graphical representations of the lander and rover and the sequence and spatial locations at which rover data were taken. As the rover moved, graphical models of the rover were added for each position that could be uniquely determined using stereo images of the rover taken by the IMP. Images taken by the rover were projected into the model as two-dimensional 'billboards' to show the proper perspective of these images.

    NOTE: original caption as published in Science Magazine

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology (Caltech).

  2. Overhead View of Area Surrounding Pathfinder

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Overhead view of the area surrounding the Pathfinder lander illustrating the Sojourner traverse. Red rectangles are rover positions at the end of sols 1-30. Locations of soil mechanics experiments, wheel abrasion experiments, and APXS measurements are shown. The A numbers refer to APXS measurements as discussed in the paper by Rieder et al. (p. 1770, Science Magazine, see image note). Coordinates are given in the LL frame.

    The photorealistic, interactive, three-dimensional virtual reality (VR) terrain models were created from IMP images using a software package developed for Pathfinder by C. Stoker et al. as a participating science project. By matching features in the left and right camera, an automated machine vision algorithm produced dense range maps of the nearfield, which were projected into a three-dimensional model as a connected polygonal mesh. Distance and angle measurements can be made on features viewed in the model using a mouse-driven three-dimensional cursor and a point-and-click interface. The VR model also incorporates graphical representations of the lander and rover and the sequence and spatial locations at which rover data were taken. As the rover moved, graphical models of the rover were added for each position that could be uniquely determined using stereo images of the rover taken by the IMP. Images taken by the rover were projected into the model as two-dimensional 'billboards' to show the proper perspective of these images.

    NOTE: original caption as published in Science Magazine

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology (Caltech).

  3. 2. OVERHEAD CHEMICAL PROCESS PIPING BETWEEN BUILDINGS 422, ON RIGHT, ...

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

    2. OVERHEAD CHEMICAL PROCESS PIPING BETWEEN BUILDINGS 422, ON RIGHT, AND 431, ON LEFT. - Rocky Mountain Arsenal, Crude Mustard & Aldrin Manufacturing, 1200 feet South of December Seventh Avenue; 600 feet East of D Street, Commerce City, Adams County, CO

  4. Overhead Projector Demonstrations: Tilted TOPS: Inclined Plane Projection.

    ERIC Educational Resources Information Center

    Alyea, Hubert N.

    1989-01-01

    The construction and uses of a device to facilitate the use of an overhead projector to show chemical reactions is presented. Materials and instructions for construction as well as reactor vessels are discussed. (CW)

  5. Childhood cancer and overhead powerlines: a case-control study.

    PubMed Central

    Myers, A.; Clayden, A. D.; Cartwright, R. A.; Cartwright, S. C.

    1990-01-01

    A case-control study has been carried out to examine the occurrence of childhood cancer in relation to the proximity of overhead power lines to a child's home address at birth and to the calculated magnetic field at the address. The study included 374 cases diagnosed in the Yorkshire Health Region between 1970 and 1979, together with 588 matched controls. Magnetic-field strengths at the birth addresses due to the load currents of overhead power lines were calculated on the basis of line-network maps and load records. The results indicate no association between the occurrence of childhood malignancies and either the proximity or the magnetic fields of overhead lines, although the statistical power of the study was limited by the small numbers of children living close to overhead power lines. PMID:2257204

  6. New rain shed (Building No. 241), overhead pipeline and raw ...

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

    New rain shed (Building No. 241), overhead pipeline and raw water tank T4. Distribution pump house can be seen at the center of building. - Hawaii Volcanoes National Park Water Collection System, Hawaii Volcanoes National Park, Volcano, Hawaii County, HI

  7. Overhead Projector Demonstrations: A Classroom Demonstration of Aliphatic Substitution.

    ERIC Educational Resources Information Center

    Perina, Ivo; Mihanovic, Branka

    1989-01-01

    Presents a halogen substitution of an alkane using a compartmentalized Petri dish or Conway dish on an overhead projector. Provides methodology and several modifications for different reactions. Uses hexane, methyl orange, bromine, and silver nitrate. (MVL)

  8. OVERHEAD VIEW OF VIVIANNA WORKS ORE BIN LOOKING NORTHEAST. GENERATOR ...

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

    OVERHEAD VIEW OF VIVIANNA WORKS ORE BIN LOOKING NORTHEAST. GENERATOR BUILDING TOP LEFT, OFFICE AND STOREROOM TOP CENTER, ROTARY KILN AND CONDENSER PLATFORM RIGHT. - Mariscal Quicksilver Mine & Reduction Works, Terlingua, Brewster County, TX

  9. 24. OVERHEAD VIEW OF MARISCAL WORKS ORE BIN FOUNDATION AND ...

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

    24. OVERHEAD VIEW OF MARISCAL WORKS ORE BIN FOUNDATION AND CONDENSERS, TOWARD WHERE ORE DELIVERY TRACK WOULD HAVE RUN, LOOKING NORTHEAST. - Mariscal Quicksilver Mine & Reduction Works, Terlingua, Brewster County, TX

  10. OVERHEAD VIEW OF MARISCAL WORKS ORE BIN FOUNDATION AND CONDENSERS, ...

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

    OVERHEAD VIEW OF MARISCAL WORKS ORE BIN FOUNDATION AND CONDENSERS, TOWARD WHERE ORE DELIVERY TRACK WOULD HAVE RUN, LOOKING NORTHEAST. - Mariscal Quicksilver Mine & Reduction Works, Terlingua, Brewster County, TX

  11. 22. GENERAL OVERHEAD VIEW OF MARISCAL WORKS, SHOWING ORE BIN, ...

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

    22. GENERAL OVERHEAD VIEW OF MARISCAL WORKS, SHOWING ORE BIN, LEFT, CONDENSERS, CENTER, AND CIRCULAR REDWOOD TANK PLATFORMS, RIGHT, LOOKING EAST, NORTHEAST. - Mariscal Quicksilver Mine & Reduction Works, Terlingua, Brewster County, TX

  12. GENERAL OVERHEAD VIEW OF MARISCAL WORKS, SHOWING ORE BIN, LEFT, ...

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

    GENERAL OVERHEAD VIEW OF MARISCAL WORKS, SHOWING ORE BIN, LEFT, CONDENSERS, CENTER, AND CIRCULAR REDWOOD TANK PLATFORMS, RIGHT, LOOKING EAST, NORTHEAST. - Mariscal Quicksilver Mine & Reduction Works, Terlingua, Brewster County, TX

  13. 35. OVERHEAD VIEW OF VIVIANNA WORKS ORE BIN LOOKING NORTHEAST. ...

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

    35. OVERHEAD VIEW OF VIVIANNA WORKS ORE BIN LOOKING NORTHEAST. GENERATOR BUILDING TOP LEFT, OFFICE AND STOREROOM TOP CENTER, ROTARY KILN AND CONDENSER PLATFORM RIGHT. - Mariscal Quicksilver Mine & Reduction Works, Terlingua, Brewster County, TX

  14. 16. VIEW OF OVERHEAD DOOR TO HOP DRYER NO. 3. ...

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

    16. VIEW OF OVERHEAD DOOR TO HOP DRYER NO. 3. ALL EIGHT HOP DRYERS ARE ON THE SECOND FLOOR. - James W. Seavey Hop Driers, 0.6 mile East from junction of Highway 99 & Alexander Avenue, Corvallis, Benton County, OR

  15. 59. SECOND FLOOR, STEEL OVERHEAD CONVEYOR SUPPORT FRAMEWORK ABUTTING FOOTBRIDGE, ...

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

    59. SECOND FLOOR, STEEL OVERHEAD CONVEYOR SUPPORT FRAMEWORK ABUTTING FOOTBRIDGE, BAY 18, TO SOUTHEAST - Ford Motor Company Edgewater Assembly Plant, Assembly Building, 309 River Road, Edgewater, Bergen County, NJ

  16. Southeast corner with overhead crane in foreground Bureau of ...

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

    Southeast corner with overhead crane in foreground - Bureau of Mines Boulder City Experimental Station, Titanium Development Plant, Date Street north of U.S. Highway 93, Boulder City, Clark County, NV

  17. 9. VIEW SOUTH OF TURBINE ROOM INTERIOR, WITH OVERHEAD CRANE; ...

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

    9. VIEW SOUTH OF TURBINE ROOM INTERIOR, WITH OVERHEAD CRANE; ABANDONED ARMATURES IN CENTER FOREGROUND; BUS PANEL REMAINS AT LOWER RIGHT CENTER - Turners Falls Power & Electric Company, Hampden Station, East bank of Connecticut River, Chicopee, Hampden County, MA

  18. 7. VIEW SHOWING EAST ELEVATION OF OVERHEAD BRIDGE CONNECTING NAPPING ...

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

    7. VIEW SHOWING EAST ELEVATION OF OVERHEAD BRIDGE CONNECTING NAPPING BUILDING (LEFT) WITH CLOTH ROOM (RIGHT), LOOKING WEST - Massachusetts Mills, Cloth Room-Section 15, 95 Bridge Street, Lowell, Middlesex County, MA

  19. 12. Interior view, grain tanks (bins). Profile view of overhead ...

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

    12. Interior view, grain tanks (bins). Profile view of overhead (fill) conveyor gallery bridge extending through tops of tanks just below roofs. - Saint Anthony Elevator No. 3, 620 Malcom Avenue, Southeast, Minneapolis, Hennepin County, MN

  20. Detail, east side, north end, showing door and overhead rail ...

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

    Detail, east side, north end, showing door and overhead rail for refrigeration room. - Fitzsimons General Hospital, Ice Plant, Southwest Corner of East I Avenue & North Thirteenth Street, Aurora, Adams County, CO

  1. INTERIOR VIEW OF THE OVERHEAD GARAGE DOOR. SHOWING THE LARGE ...

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

    INTERIOR VIEW OF THE OVERHEAD GARAGE DOOR. SHOWING THE LARGE OPENING WITH CAST STONE SILL IN THE EXTERIOR GARAGE WALL AT LEFT. VIEW FACING NORTHWEST. - Hickam Field, Officers' Housing Type F, 602 Beard Avenue, Honolulu, Honolulu County, HI

  2. 28. SHOWER AND URINALS, OVERHEAD TOILET STRUCTURE ABOVE ROOF PANEL ...

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

    28. SHOWER AND URINALS, OVERHEAD TOILET STRUCTURE ABOVE ROOF PANEL STORAGE AREA. VIEW TO SOUTH-SOUTHWEST. - Ford Motor Company Long Beach Assembly Plant, Assembly Building, 700 Henry Ford Avenue, Long Beach, Los Angeles County, CA

  3. 27. OVERHEAD TOILET, SHOWER, CHANGE ROOM STRUCTURE. VIEW TO NORTHNORTHEAST. ...

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

    27. OVERHEAD TOILET, SHOWER, CHANGE ROOM STRUCTURE. VIEW TO NORTH-NORTHEAST. - Ford Motor Company Long Beach Assembly Plant, Assembly Building, 700 Henry Ford Avenue, Long Beach, Los Angeles County, CA

  4. INTERIOR VIEW, SETTING LARGE CORE WITH ASSISTANCE FROM THE OVERHEAD ...

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

    INTERIOR VIEW, SETTING LARGE CORE WITH ASSISTANCE FROM THE OVERHEAD RAIL CRANE IN BOX FLOOR MOLD AREA (WORKERS: DAN T. WELLS AND TRUMAN CARLISLE). - Stockham Pipe & Fittings Company, Ductile Iron Foundry, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  5. Overhead Projector Demonstrations: Tilted TOPS: Inclined Plane Projection.

    ERIC Educational Resources Information Center

    Alyea, Hubert N.

    1989-01-01

    The construction and uses of a device to facilitate the use of an overhead projector to show chemical reactions is presented. Materials and instructions for construction as well as reactor vessels are discussed. (CW)

  6. 161. BLACKSMITH SHOP, OVERHEAD SHAFT. BELT ON LEFT CONNECTS TO ...

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

    161. BLACKSMITH SHOP, OVERHEAD SHAFT. BELT ON LEFT CONNECTS TO SHAFTS WHICH RUN POWER PRESS AND HYDRAULIC TIRE SETTER. - Gruber Wagon Works, Pennsylvania Route 183 & State Hill Road at Red Bridge Park, Bernville, Berks County, PA

  7. Overhead Projector Demonstrations: A Classroom Demonstration of Aliphatic Substitution.

    ERIC Educational Resources Information Center

    Perina, Ivo; Mihanovic, Branka

    1989-01-01

    Presents a halogen substitution of an alkane using a compartmentalized Petri dish or Conway dish on an overhead projector. Provides methodology and several modifications for different reactions. Uses hexane, methyl orange, bromine, and silver nitrate. (MVL)

  8. Looking north toward unit 1 pump motor, overhead crane, and ...

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

    Looking north toward unit 1 pump motor, overhead crane, and double folding doors on the north side of the building - Wellton-Mohawk Irrigation System, Pumping Plant No. 2, Bounded by Interstate 8 to south, Wellton, Yuma County, AZ

  9. 2. TYPICAL OVERHEAD WIRE CONSTRUCTION CURVE GUY WIRE ARRANGEMENT ...

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

    2. TYPICAL OVERHEAD WIRE CONSTRUCTION - CURVE GUY WIRE ARRANGEMENT (ABANDONED WEST LEG OF WYE AT SIXTH AVENUE AND PINE STREET) - Yakima Valley Transportation Company Interurban Railroad, Trackage, Yakima, Yakima County, WA

  10. 14. INTERIOR, INSPECTION PITS AND OVERHEAD CATWALKS, FACING WEST ...

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

    14. INTERIOR, INSPECTION PITS AND OVERHEAD CATWALKS, FACING WEST - Delaware, Lackawanna & Western Railroad Freight & Rail Yard, Multiple Unit Light Inspection Shed, New Jersey Transit Hoboken Terminal Rail Yard, Hoboken, Hudson County, NJ

  11. 13. DETAIL, LATERAL BRACING FOR INTERIOR OVERHEAD CRANE Delaware, ...

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

    13. DETAIL, LATERAL BRACING FOR INTERIOR OVERHEAD CRANE - Delaware, Lackawanna & Western Railroad Freight & Rail Yard, Multiple Unit Light Inspection Shed, New Jersey Transit Hoboken Terminal Rail Yard, Hoboken, Hudson County, NJ

  12. 17. INTERIOR, INSPECTION PITS, OVERHEAD CRANE SUPPORT AND CAR JACKING ...

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

    17. INTERIOR, INSPECTION PITS, OVERHEAD CRANE SUPPORT AND CAR JACKING PADS, FACING EAST - Delaware, Lackawanna & Western Railroad Freight & Rail Yard, Multiple Unit Light Inspection Shed, New Jersey Transit Hoboken Terminal Rail Yard, Hoboken, Hudson County, NJ

  13. INTERIOR VIEW OF SHED, SHOWING STRUCTURAL SYSTEM AND OVERHEAD DOOR ...

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

    INTERIOR VIEW OF SHED, SHOWING STRUCTURAL SYSTEM AND OVERHEAD DOOR MOUNTING, LOOKING NORTHEAST - Marvine Colliery, Shed, West side Boulevard Avenue, between East Parker Street & Route 380, Scranton, Lackawanna County, PA

  14. WEST ELEVATION, CAMERA FACING EAST. THE OVERHEAD PIPES ARE FOR ...

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

    WEST ELEVATION, CAMERA FACING EAST. THE OVERHEAD PIPES ARE FOR DISTRIBUTING STEAM FROM THE NEARBY HEATING PLANT TO VARIOUS PARTS OF THE COMPLEX. - New Haven Rail Yard, Oil Storage Building, Vicinity of Union Avenue, New Haven, New Haven County, CT

  15. Interior view of main section of milk barn. Opening overhead ...

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

    Interior view of main section of milk barn. Opening overhead leads to attic crawl space. Camera is pointed SW. - Kosai Farm, Milk Barn, B Street north of Northwest Twenty-ninth Street, Auburn, King County, WA

  16. 13. TURNING DEVICE SUSPENDED FROM, AND LIFTED BY THE OVERHEAD ...

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

    13. TURNING DEVICE SUSPENDED FROM, AND LIFTED BY THE OVERHEAD CRANE SYSTEM EAST OF No. 1 PRESS. - U.S. Steel Homestead Works, Press Shop No. 1, Along Monongahela River, Homestead, Allegheny County, PA

  17. 7. Ball mill area and second level entry with overhead ...

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

    7. Ball mill area and second level entry with overhead crane in background - Bureau of Mines Boulder City Experimental Station, Ore Dressing Pilot Plant, Date Street north of U.S. Highway 93, Boulder City, Clark County, NV

  18. 4. SOUTHWARD OVERHEAD VIEW OF INGOT TRANSFER TRACKS AND INGOT ...

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

    4. SOUTHWARD OVERHEAD VIEW OF INGOT TRANSFER TRACKS AND INGOT BUGGY ADJACENT TO SOAKING PITS ON RIGHT, IN THE PRIMARY MILL BUILDING. - U.S. Steel Duquesne Works, Primary Mill, Along Monongahela River, Duquesne, Allegheny County, PA

  19. TOWER SECOND FLOOR INTERIOR, LOOKING WEST, SHOWING OVERHEAD TRACK DIAGRAM, ...

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

    TOWER SECOND FLOOR INTERIOR, LOOKING WEST, SHOWING OVERHEAD TRACK DIAGRAM, OPERATING LEVERS (BEING PULLED BY OPERATOR TOM HARTMAN), AND AUXILIARY TRACK DIAGRAM ABOVE DESK AT LEFT. - Baltimore & Ohio Railroad, Z Tower, State Route 46, Keyser, Mineral County, WV

  20. The voltage-dependent K+ channels Kv1.3 and Kv1.5 in human cancer

    PubMed Central

    Comes, Núria; Bielanska, Joanna; Vallejo-Gracia, Albert; Serrano-Albarrás, Antonio; Marruecos, Laura; Gómez, Diana; Soler, Concepció; Condom, Enric; Ramón y Cajal, Santiago; Hernández-Losa, Javier; Ferreres, Joan C.; Felipe, Antonio

    2013-01-01

    Voltage-dependent K+ channels (Kv) are involved in a number of physiological processes, including immunomodulation, cell volume regulation, apoptosis as well as differentiation. Some Kv channels participate in the proliferation and migration of normal and tumor cells, contributing to metastasis. Altered expression of Kv1.3 and Kv1.5 channels has been found in several types of tumors and cancer cells. In general, while the expression of Kv1.3 apparently exhibits no clear pattern, Kv1.5 is induced in many of the analyzed metastatic tissues. Interestingly, evidence indicates that Kv1.5 channel shows inversed correlation with malignancy in some gliomas and non-Hodgkin's lymphomas. However, Kv1.3 and Kv1.5 are similarly remodeled in some cancers. For instance, expression of Kv1.3 and Kv1.5 correlates with a certain grade of tumorigenicity in muscle sarcomas. Differential remodeling of Kv1.3 and Kv1.5 expression in human cancers may indicate their role in tumor growth and their importance as potential tumor markers. However, despite of this increasing body of information, which considers Kv1.3 and Kv1.5 as emerging tumoral markers, further research must be performed to reach any conclusion. In this review, we summarize what it has been lately documented about Kv1.3 and Kv1.5 channels in human cancer. PMID:24133455

  1. The voltage-dependent K(+) channels Kv1.3 and Kv1.5 in human cancer.

    PubMed

    Comes, Núria; Bielanska, Joanna; Vallejo-Gracia, Albert; Serrano-Albarrás, Antonio; Marruecos, Laura; Gómez, Diana; Soler, Concepció; Condom, Enric; Ramón Y Cajal, Santiago; Hernández-Losa, Javier; Ferreres, Joan C; Felipe, Antonio

    2013-10-10

    Voltage-dependent K(+) channels (Kv) are involved in a number of physiological processes, including immunomodulation, cell volume regulation, apoptosis as well as differentiation. Some Kv channels participate in the proliferation and migration of normal and tumor cells, contributing to metastasis. Altered expression of Kv1.3 and Kv1.5 channels has been found in several types of tumors and cancer cells. In general, while the expression of Kv1.3 apparently exhibits no clear pattern, Kv1.5 is induced in many of the analyzed metastatic tissues. Interestingly, evidence indicates that Kv1.5 channel shows inversed correlation with malignancy in some gliomas and non-Hodgkin's lymphomas. However, Kv1.3 and Kv1.5 are similarly remodeled in some cancers. For instance, expression of Kv1.3 and Kv1.5 correlates with a certain grade of tumorigenicity in muscle sarcomas. Differential remodeling of Kv1.3 and Kv1.5 expression in human cancers may indicate their role in tumor growth and their importance as potential tumor markers. However, despite of this increasing body of information, which considers Kv1.3 and Kv1.5 as emerging tumoral markers, further research must be performed to reach any conclusion. In this review, we summarize what it has been lately documented about Kv1.3 and Kv1.5 channels in human cancer.

  2. Shoulder problems in overhead sports. Part I - biomechanics of throwing.

    PubMed

    Kaczmarek, Piotr Krzysztof; Lubiatowski, Przemysław; Cisowski, Paweł; Grygorowicz, Monika; Łepski, Marcin; Długosz, Jan; Ogrodowicz, Piotr; Dudziński, Witold; Nowak, Maciej; Romanowski, Leszek

    2014-05-15

    The article discusses the biomechanical processes that occur during an overhead throw. This activity is highly specialized and requires full and proper function from the shoulder joint. It consists of active and passive stabilization and synchronous work of the accelerating and decelerating muscles. The process of the overhead throw can be divided into several phases that differ from each other in biomechanical parameters and involvement of specific muscles.

  3. 16. THE INSTALLATION OF CONVEYORS AND OVERHEAD RAILS ELIMINATED THE ...

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

    16. THE INSTALLATION OF CONVEYORS AND OVERHEAD RAILS ELIMINATED THE NEED TO LAY MOLDS OUT ON FLOORS AND HAND-POUR THEM. INSTEAD, WORKERS PULLED LARGE LADLES ALONG OVERHEAD RAILS AND FILLED CONVEYOR-DRIVEN MOLDS WHILE THEY STOOD ON A MOVING PLATFORM THAT TRAVELED AT THE SAME SPEED AS THE MOLD CONVEYOR, CA. 1950. - Stockham Pipe & Fittings Company, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  4. Computer-based mechanical design of overhead lines

    NASA Astrophysics Data System (ADS)

    Rusinaru, D.; Bratu, C.; Dinu, R. C.; Manescu, L. G.

    2016-02-01

    Beside the performance, the safety level according to the actual standards is a compulsory condition for distribution grids’ operation. Some of the measures leading to improvement of the overhead lines reliability ask for installations’ modernization. The constraints imposed to the new lines components refer to the technical aspects as thermal stress or voltage drop, and look for economic efficiency, too. The mechanical sizing of the overhead lines is after all an optimization problem. More precisely, the task in designing of the overhead line profile is to size poles, cross-arms and stays and locate poles along a line route so that the total costs of the line's structure to be minimized and the technical and safety constraints to be fulfilled.The authors present in this paper an application for the Computer-Based Mechanical Design of the Overhead Lines and the features of the corresponding Visual Basic program, adjusted to the distribution lines. The constraints of the optimization problem are adjusted to the existing weather and loading conditions of Romania. The outputs of the software application for mechanical design of overhead lines are: the list of components chosen for the line: poles, cross-arms, stays; the list of conductor tension and forces for each pole, cross-arm and stay for different weather conditions; the line profile drawings.The main features of the mechanical overhead lines design software are interactivity, local optimization function and high-level user-interface

  5. Clouds Sailing Overhead on Mars, Unenhanced

    NASA Image and Video Library

    2017-08-09

    Wispy clouds float across the Martian sky in this accelerated sequence of images from NASA's Curiosity Mars rover. The rover's Navigation Camera (Navcam) took these eight images over a span of four minutes early in the morning of the mission's 1,758th Martian day, or sol (July 17, 2017), aiming nearly straight overhead. This sequence uses raw images, which include a bright ring around the center of the frame that is an artifact of sunlight striking the camera lens even though the Sun is not in the shot. A processed version removing that artifact and emphasizing changes between images is also available. The clouds resemble Earth's cirrus clouds, which are ice crystals at high altitudes. These Martian clouds are likely composed of crystals of water ice that condense onto dust grains in the cold Martian atmosphere. Cirrus wisps appear as ice crystals fall and evaporate in patterns known as "fall streaks" or "mare's tails." Such patterns have been seen before at high latitudes on Mars, for instance by the Phoenix Mars Lander in 2008, and seasonally nearer the equator, for instance by the Opportunity rover. However, Curiosity has not previously observed such clouds so clearly visible from the rover's study area about five degrees south of the equator. The Hubble Space Telescope and spacecraft orbiting Mars have observed a band of clouds to appear near the Martian equator around the time of the Martian year when the planet is farthest from the Sun. With a more elliptical orbit than Earth's, Mars experiences more annual variation than Earth in its distance from the Sun. The most distant point in an orbit around the Sun is called the aphelion. The near-equatorial Martian cloud pattern observed at that time of year is called the "aphelion cloud belt." These new images from Curiosity were taken about two months before aphelion, but the morning clouds observed may be an early stage of the aphelion cloud belt. An animation is available at https

  6. Clouds Sailing Overhead on Mars, Enhanced

    NASA Image and Video Library

    2017-08-09

    Wispy clouds float across the Martian sky in this accelerated sequence of enhanced images from NASA's Curiosity Mars rover. The rover's Navigation Camera (Navcam) took these eight images over a span of four minutes early in the morning of the mission's 1,758th Martian day, or sol (July 17, 2017), aiming nearly straight overhead. They have been processed by first making a "flat field' adjustment for known differences in sensitivity among pixels and correcting for camera artifacts due to light reflecting within the camera, and then generating an "average" of all the frames and subtracting that average from each frame. This subtraction results in emphasizing any changes due to movement or lighting. The clouds are also visible, though fainter, in a raw image sequence from these same observations. On the same Martian morning, Curiosity also observed clouds near the southern horizon. The clouds resemble Earth's cirrus clouds, which are ice crystals at high altitudes. These Martian clouds are likely composed of crystals of water ice that condense onto dust grains in the cold Martian atmosphere. Cirrus wisps appear as ice crystals fall and evaporate in patterns known as "fall streaks" or "mare's tails." Such patterns have been seen before at high latitudes on Mars, for instance by the Phoenix Mars Lander in 2008, and seasonally nearer the equator, for instance by the Opportunity rover. However, Curiosity has not previously observed such clouds so clearly visible from the rover's study area about five degrees south of the equator. The Hubble Space Telescope and spacecraft orbiting Mars have observed a band of clouds to appear near the Martian equator around the time of the Martian year when the planet is farthest from the Sun. With a more elliptical orbit than Earth's, Mars experiences more annual variation than Earth in its distance from the Sun. The most distant point in an orbit around the Sun is called the aphelion. The near-equatorial Martian cloud pattern observed at

  7. Conserved Negative Charges in the N-terminal Tetramerization Domain Mediate Efficient Assembly of Kv2.1 and Kv2.1/Kv6.4 Channels*

    PubMed Central

    Bocksteins, Elke; Labro, Alain J.; Mayeur, Evy; Bruyns, Tine; Timmermans, Jean-Pierre; Adriaensen, Dirk; Snyders, Dirk J.

    2009-01-01

    Voltage-gated potassium (Kv) channels are transmembrane tetramers of individual α-subunits. Eight different Shaker-related Kv subfamilies have been identified in which the tetramerization domain T1, located on the intracellular N terminus, facilitates and controls the assembly of both homo- and heterotetrameric channels. Only the Kv2 α-subunits are able to form heterotetramers with members of the silent Kv subfamilies (Kv5, Kv6, Kv8, and Kv9). The T1 domain contains two subdomains, A and B box, which presumably determine subfamily specificity by preventing incompatible subunits to assemble. In contrast, little is known about the involvement of the A/B linker sequence. Both Kv2 and silent Kv subfamilies contain a fully conserved and negatively charged sequence (CDD) in this linker that is lacking in the other subfamilies. Neutralizing these aspartates in Kv2.1 by mutating them to alanines did not affect the gating properties, but reduced the current density moderately. However, charge reversal arginine substitutions strongly reduced the current density of these homotetrameric mutant Kv2.1 channels and immunocytochemistry confirmed the reduced expression at the plasma membrane. Förster resonance energy transfer measurements using confocal microscopy showed that the latter was not due to impaired trafficking, but to a failure to assemble the tetramer. This was further confirmed with co-immunoprecipitation experiments. The corresponding arginine substitution in Kv6.4 prevented its heterotetrameric interaction with Kv2.1. These results indicate that these aspartates (especially the first one) in the A/B box linker of the T1 domain are required for efficient assembly of both homotetrameric Kv2.1 and heterotetrameric Kv2.1/silent Kv6.4 channels. PMID:19717558

  8. Functional assembly of Kv7.1/Kv7.5 channels with emerging properties on vascular muscle physiology.

    PubMed

    Oliveras, Anna; Roura-Ferrer, Meritxell; Solé, Laura; de la Cruz, Alicia; Prieto, Angela; Etxebarria, Ainhoa; Manils, Joan; Morales-Cano, Daniel; Condom, Enric; Soler, Concepció; Cogolludo, Angel; Valenzuela, Carmen; Villarroel, Alvaro; Comes, Núria; Felipe, Antonio

    2014-07-01

    Voltage-dependent K(+) (Kv) channels from the Kv7 family are expressed in blood vessels and contribute to cardiovascular physiology. Although Kv7 channel blockers trigger muscle contractions, Kv7 activators act as vasorelaxants. Kv7.1 and Kv7.5 are expressed in many vessels. Kv7.1 is under intense investigation because Kv7.1 blockers fail to modulate smooth muscle reactivity. In this study, we analyzed whether Kv7.1 and Kv7.5 may form functional heterotetrameric channels increasing the channel diversity in vascular smooth muscles. Kv7.1 and Kv7.5 currents elicited in arterial myocytes, oocyte, and mammalian expression systems suggest the formation of heterotetrameric complexes. Kv7.1/Kv7.5 heteromers, exhibiting different pharmacological characteristics, participate in the arterial tone. Kv7.1/Kv7.5 associations were confirmed by coimmunoprecipitation, fluorescence resonance energy transfer, and fluorescence recovery after photobleaching experiments. Kv7.1/Kv7.5 heterotetramers were highly retained at the endoplasmic reticulum. Studies in HEK-293 cells, heart, brain, and smooth and skeletal muscles demonstrated that the predominant presence of Kv7.5 stimulates release of Kv7.1/Kv7.5 oligomers out of lipid raft microdomains. Electrophysiological studies supported that KCNE1 and KCNE3 regulatory subunits further increased the channel diversity. Finally, the analysis of rat isolated myocytes and human blood vessels demonstrated that Kv7.1 and Kv7.5 exhibited a differential expression, which may lead to channel diversity. Kv7.1 and Kv7.5 form heterotetrameric channels increasing the diversity of structures which fine-tune blood vessel reactivity. Because the lipid raft localization of ion channels is crucial for cardiovascular physiology, Kv7.1/Kv7.5 heteromers provide efficient spatial and temporal regulation of smooth muscle function. Our results shed light on the debate about the contribution of Kv7 channels to vasoconstriction and hypertension. © 2014 American

  9. Asymmetric resting scapular posture in healthy overhead athletes.

    PubMed

    Oyama, Sakiko; Myers, Joseph B; Wassinger, Craig A; Daniel Ricci, R; Lephart, Scott M

    2008-01-01

    Observation of the scapular posture is one of the most important components of the physical examination in overhead athletes. Postural asymmetry is typically considered to be associated with injuries. However, asymmetry in the overhead athlete's scapula may be normal due to the dominant use of the limb. To quantify the differences in resting scapular posture between the dominant and nondominant sides in 3 groups of healthy overhead athletes (baseball pitchers, volleyball players, and tennis players) using an electromagnetic tracking device. Cross-sectional design. University-based biomechanics laboratory. A total of 43 players participated, including 15 baseball pitchers, 15 volleyball players, and 13 tennis players. All participants were healthy college-aged men. Bilateral 3-dimensional scapular kinematics with the arm at rest were measured using an electromagnetic tracking device. Bilateral scapular position and orientation were measured. Between-groups and between-sides differences in each variable were analyzed using separate analyses of variance. In tennis players, the scapula was more protracted on the dominant side than on the nondominant side (P < .05). In all overhead athletes, the dominant-side scapula was more internally rotated (P = .001) and anteriorly tilted (P = .001) than the nondominant-side scapula was. The dominant-side scapula of the overhead athletes was more internally rotated and anteriorly tilted than the nondominant-side scapula. The dominant-side scapula of the tennis players was more protracted than that on the nondominant side. Clinicians evaluating overhead athletes need to recognize that scapular posture asymmetry in unilateral overhead athletes may be normal. Our results emphasize the importance of the baseline evaluation in this population in order to accurately assess pathologic change in bilateral scapular positions and orientations after injury.

  10. Asymmetric Resting Scapular Posture in Healthy Overhead Athletes

    PubMed Central

    Oyama, Sakiko; Myers, Joseph B; Wassinger, Craig A; Daniel Ricci, R; Lephart, Scott M

    2008-01-01

    Context: Observation of the scapular posture is one of the most important components of the physical examination in overhead athletes. Postural asymmetry is typically considered to be associated with injuries. However, asymmetry in the overhead athlete's scapula may be normal due to the dominant use of the limb. Objective: To quantify the differences in resting scapular posture between the dominant and nondominant sides in 3 groups of healthy overhead athletes (baseball pitchers, volleyball players, and tennis players) using an electromagnetic tracking device. Design: Cross-sectional design. Setting: University-based biomechanics laboratory. Patients or Other Participants: A total of 43 players participated, including 15 baseball pitchers, 15 volleyball players, and 13 tennis players. All participants were healthy college-aged men. Intervention(s): Bilateral 3-dimensional scapular kinematics with the arm at rest were measured using an electromagnetic tracking device. Main Outcome Measure(s): Bilateral scapular position and orientation were measured. Between-groups and between-sides differences in each variable were analyzed using separate analyses of variance. Results: In tennis players, the scapula was more protracted on the dominant side than on the nondominant side (P < .05). In all overhead athletes, the dominant-side scapula was more internally rotated (P  =  .001) and anteriorly tilted (P  =  .001) than the nondominant-side scapula was. Conclusions: The dominant-side scapula of the overhead athletes was more internally rotated and anteriorly tilted than the nondominant-side scapula. The dominant-side scapula of the tennis players was more protracted than that on the nondominant side. Clinicians evaluating overhead athletes need to recognize that scapular posture asymmetry in unilateral overhead athletes may be normal. Our results emphasize the importance of the baseline evaluation in this population in order to accurately assess pathologic change in

  11. Functional analysis of Kv1.2 and paddle chimera Kv channels in planar lipid bilayers

    PubMed Central

    Tao, Xiao; MacKinnon, Roderick

    2010-01-01

    Summary Voltage-dependent K+ channels play key roles in shaping electrical signaling in both excitable as well as non-excitable cells. These channels open and close in response to the voltage changes across the cell membrane. Many studies have been carried out in order to understand the voltage sensing mechanism. Our laboratory recently determined the atomic structures of a mammalian voltage-dependent K+ channel Kv1.2 and a mutant of Kv1.2 named the ‘paddle-chimera’ channel, in which the voltage sensor paddle was transferred from Kv2.1 to Kv1.2. These two structures provide atomic descriptions of voltage-dependent channels with unprecedented clarity. Until now the functional integrity of these two channels biosynthesized in yeast cells have not been assessed. Here we report the electrophysiological and pharmacological properties of Kv1.2 and the paddle chimera channels in planar lipid bilayers. We demonstrate that Pichia yeast produce ‘normally functioning’ mammalian voltage-dependent K+ channels with qualitatively similar features to the Shaker K+ channel in the absence of the N-terminal inactivation gate, and that the paddle chimera mutant channel functions as well as Kv1.2. We find, however, that in several respects the Kv1.2 channel exhibits functional properties that are distinct from Kv1.2 channels reported in the literature. PMID:18638484

  12. Redistribution of Kv1 and Kv7 enhances neuronal excitability during structural axon initial segment plasticity

    PubMed Central

    Kuba, Hiroshi; Yamada, Rei; Ishiguro, Go; Adachi, Ryota

    2015-01-01

    Structural plasticity of the axon initial segment (AIS), the trigger zone of neurons, is a powerful means for regulating neuronal activity. Here, we show that AIS plasticity is not limited to structural changes; it also occurs as changes in ion-channel expression, which substantially augments the efficacy of regulation. In the avian cochlear nucleus, depriving afferent inputs by removing cochlea elongated the AIS, and simultaneously switched the dominant Kv channels at the AIS from Kv1.1 to Kv7.2. Due to the slow activation kinetics of Kv7.2, the redistribution of the Kv channels reduced the shunting conductance at the elongated AIS during the initiation of action potentials and effectively enhanced the excitability of the deprived neurons. The results indicate that the functional plasticity of the AIS works cooperatively with the structural plasticity and compensates for the loss of afferent inputs to maintain the homeostasis of auditory circuits after hearing loss by cochlea removal. PMID:26581625

  13. Redistribution of Kv1 and Kv7 enhances neuronal excitability during structural axon initial segment plasticity.

    PubMed

    Kuba, Hiroshi; Yamada, Rei; Ishiguro, Go; Adachi, Ryota

    2015-11-19

    Structural plasticity of the axon initial segment (AIS), the trigger zone of neurons, is a powerful means for regulating neuronal activity. Here, we show that AIS plasticity is not limited to structural changes; it also occurs as changes in ion-channel expression, which substantially augments the efficacy of regulation. In the avian cochlear nucleus, depriving afferent inputs by removing cochlea elongated the AIS, and simultaneously switched the dominant Kv channels at the AIS from Kv1.1 to Kv7.2. Due to the slow activation kinetics of Kv7.2, the redistribution of the Kv channels reduced the shunting conductance at the elongated AIS during the initiation of action potentials and effectively enhanced the excitability of the deprived neurons. The results indicate that the functional plasticity of the AIS works cooperatively with the structural plasticity and compensates for the loss of afferent inputs to maintain the homeostasis of auditory circuits after hearing loss by cochlea removal.

  14. CURRENT CONCEPTS IN SHOULDER EXAMINATION OF THE OVERHEAD ATHLETE

    PubMed Central

    Ellenbecker, Todd

    2013-01-01

    Examination of the shoulder complex has long been described as challenging. This is particularly true in the examination of the overhead athlete who has structural differences when compared to a shoulder patient who is a non‐athlete. Complexity with the examination is due to unique biomechanical and structural changes, multiple joint articulations, multiple pain patterns, and the potential of injury to structures both inside (intra‐articular) and outside (extra‐articular) the glenohumeral joint. Repetitive stresses placed on the shoulders of overhead athletes may affect range of motion, strength, scapular position, and ultimately, the integrity of soft tissue and bony structures in any of the joints that comprise the shoulder complex. Furthermore, many shoulder examination tests thought to be unique to a single structure, joint, or condition can be positive in multiple conditions. The examination of the overhead athletes shoulder, coupled with a thorough medical history will provide a solid foundation to allow a functional physical therapy diagnosis and provide clues as to the presence of the lesion (s) causing disability. The purpose of this clinical commentary is to assist the reader to understand the unique physical characteristics of the overhead athlete, which will lead to a more accurate and reproducible evaluation of athletes who sustain injuries while participating in overhead sports. Level of Evidence: 5 PMID:24175138

  15. A Reference Model for Virtual Machine Launching Overhead

    SciTech Connect

    Wu, Hao; Ren, Shangping; Garzoglio, Gabriele; Timm, Steven; Bernabeu, Gerard; Chadwick, Keith; Noh, Seo-Young

    2016-07-01

    Cloud bursting is one of the key research topics in the cloud computing communities. A well designed cloud bursting module enables private clouds to automatically launch virtual machines (VMs) to public clouds when more resources are needed. One of the main challenges in developing a cloud bursting module is to decide when and where to launch a VM so that all resources are most effectively and efficiently utilized and the system performance is optimized. However, based on system operational data obtained from FermiCloud, a private cloud developed by the Fermi National Accelerator Laboratory for scientific workflows, the VM launching overhead is not a constant. It varies with physical resource utilization, such as CPU and I/O device utilizations, at the time when a VM is launched. Hence, to make judicious decisions as to when and where a VM should be launched, a VM launching overhead reference model is needed. In this paper, we first develop a VM launching overhead reference model based on operational data we have obtained on FermiCloud. Second, we apply the developed reference model on FermiCloud and compare calculated VM launching overhead values based on the model with measured overhead values on FermiCloud. Our empirical results on FermiCloud indicate that the developed reference model is accurate. We believe, with the guidance of the developed reference model, efficient resource allocation algorithms can be developed for cloud bursting process to minimize the operational cost and resource waste.

  16. Report on Analyses of WAC Samples of Evaporator Overheads - 2004

    SciTech Connect

    Oji, L

    2005-03-18

    In November and December of 2004, the Tank Farm submitted annual samples from 2F, 2H and 3H Evaporator Overhead streams for characterization to verify compliance with the new Effluent Treatment Facility (ETF) Waste Acceptance Criteria (WAC) and to look for organic species. With the exception of slightly high ammonia in the 2F evaporator overheads and high radiation control guide number for the 3H and 2F evaporator overhead samples, all the overheads samples were found to be in compliance with the Effluent Treatment Facility WAC. The ammonium concentration in the 2F-evaporator overhead, at 33 mg/L, was above the ETF waste water collection tank (WWCT) limits of 28 mg/L. The RCG Number for the 3H and 2F evaporator samples at, respectively, 1.38E-02 and 8.24E-03 were higher than the WWCT limit of 7.69E-03. The analytical detection limits for americium-241 and radium-226 in the evaporator samples were not consistently met because of low WWCT detection limits and insufficient evaporator samples.

  17. Ergonomic Assessment of Floor-based and Overhead Lifts

    PubMed Central

    Waters, Thomas R.; Dick, Robert; Lowe, Brian; Werren, Dwight; Parsons, Kelley

    2015-01-01

    Manual full-body vertical lifts of patients have high risk for developing musculoskeletal disorders. Two primary types of battery-powered lift assist devices are available for these tasks: floor-based and overhead-mounted devices. Studies suggest that the operation of floor-based devices may require excessive pushing and pulling forces and that overhead-mounted devices are safer and require lower operating forces. This study evaluated required operating hand forces and resulting biomechanical spinal loading for overhead-mounted lifts versus floor-based lifts across various floor surfaces and patient weight conditions. We did not examine differences in how operators performed the tasks, but rather focused on differences in required operating forces and estimated biomechanical loads across various exposure conditions for a typical operator. Findings show that the floor-based lifts exceeded recommended exposure limits for pushing and pulling for many of the floor/weight conditions and that the overhead-mounted lifts did not. As expected, forces and spinal loads were greater for nonlinoleum floor surfaces compared with linoleum floors. Based on these findings, it is suggested that overhead-mounted devices be used whenever possible, particularly in instances where carpeted floors would be encountered. PMID:26550545

  18. Biceps instability and Slap type II tear in overhead athletes

    PubMed Central

    Osti, Leonardo; Soldati, Francesco; Cheli, Andrea; Pari, Carlotta; Massari, Leo; Maffulli, Nicola

    2012-01-01

    Summary Type II lesions are common lesions encountered in overhead athletes with controversies arising in term of timing for treatment, surgical approach, rehabilitation and functional results. The aim of our study was to evaluate the outcomes of arthroscopic repair of type II SLAP tears in overhead athletes, focusing on the time elapsed from diagnosis and treatment, time needed to return to sport, rate of return to sport and to previous level of performance, providing an overview concerning evidence for the effectiveness of different surgical approaches to type II SLAP tears in overhead athletes. A internet search on peer reviewed Journal from 1990, first descriprion of this pathology, to 2012, have been conducted evaluating the outcomes for both isolated Slap II tear overhead athletes and those who presented associated lesions treated. The results have been analyzed according to the scale reported focusing on return to sport and level of activity. Apart from a single study, non prospective level I and II studies were detected. Return to play at the same level ranged form 22% to 94% with different range of technique utilized with the majority of the authors recommending the fixation of these lesions but biceps tenodesis can lead to higher satisfaction racte when directly compated to the anchor fixation. Associated pathologies such as partial or full tickness rotator cuff tear did not clearly affect the outcomes and complications rate. There is no consensus regarding timing and treatment for type II SLAP, especially in overhead athletes who need to regain a high level of performance. PMID:23738307

  19. Biceps instability and Slap type II tear in overhead athletes.

    PubMed

    Osti, Leonardo; Soldati, Francesco; Cheli, Andrea; Pari, Carlotta; Massari, Leo; Maffulli, Nicola

    2012-10-01

    Type II lesions are common lesions encountered in overhead athletes with controversies arising in term of timing for treatment, surgical approach, rehabilitation and functional results. The aim of our study was to evaluate the outcomes of arthroscopic repair of type II SLAP tears in overhead athletes, focusing on the time elapsed from diagnosis and treatment, time needed to return to sport, rate of return to sport and to previous level of performance, providing an overview concerning evidence for the effectiveness of different surgical approaches to type II SLAP tears in overhead athletes. A internet search on peer reviewed Journal from 1990, first descriprion of this pathology, to 2012, have been conducted evaluating the outcomes for both isolated Slap II tear overhead athletes and those who presented associated lesions treated. The results have been analyzed according to the scale reported focusing on return to sport and level of activity. Apart from a single study, non prospective level I and II studies were detected. Return to play at the same level ranged form 22% to 94% with different range of technique utilized with the majority of the authors recommending the fixation of these lesions but biceps tenodesis can lead to higher satisfaction racte when directly compated to the anchor fixation. Associated pathologies such as partial or full tickness rotator cuff tear did not clearly affect the outcomes and complications rate. There is no consensus regarding timing and treatment for type II SLAP, especially in overhead athletes who need to regain a high level of performance.

  20. Modeling Spatial Dependencies in High-Resolution Overhead Imagery

    SciTech Connect

    Cheriyadat, Anil M; Bright, Eddie A; Vatsavai, Raju

    2011-01-01

    Human settlement regions with different physical and socio-economic attributes exhibit unique spatial characteristics that are often illustrated in high-resolution overhead imageries. For example- size, shape and spatial arrangements of man-made structures are key attributes that vary with respect to the socioeconomic profile of the neighborhood. Successfully modeling these attributes is crucial in developing advanced image understanding systems for interpreting complex aerial scenes. In this paper we present three different approaches to model the spatial context in the overhead imagery. First, we show that the frequency domain of the image can be used to model the spatial context [1]. The shape of the spectral energy contours characterize the scene context and can be exploited as global features. Secondly, we explore a discriminative framework based on the Conditional Random Fields (CRF) [2] to model the spatial context in the overhead imagery. The features derived from the edge orientation distribution calculated for a neighborhood and the associated class labels are used as input features to model the spatial context. Our third approach is based on grouping spatially connected pixels based on the low-level edge primitives to form support-regions [3]. The statistical parameters generated from the support-region feature distributions characterize different geospatial neighborhoods. We apply our approaches on high-resolution overhead imageries. We show that proposed approaches characterize the spatial context in overhead imageries.

  1. The neuronal Kv4 channel complex.

    PubMed

    Covarrubias, Manuel; Bhattacharji, Aditya; De Santiago-Castillo, Jose A; Dougherty, Kevin; Kaulin, Yuri A; Na-Phuket, Thanawath Ratanadilok; Wang, Guangyu

    2008-08-01

    Kv4 channel complexes mediate the neuronal somatodendritic A-type K(+) current (I(SA)), which plays pivotal roles in dendritic signal integration. These complexes are composed of pore-forming voltage-gated alpha-subunits (Shal/Kv4) and at least two classes of auxiliary beta-subunits: KChIPs (K(+)-Channel-Interacting-Proteins) and DPLPs (Dipeptidyl-Peptidase-Like-Proteins). Here, we review our investigations of Kv4 gating mechanisms and functional remodeling by specific auxiliary beta-subunits. Namely, we have concluded that: (1) the Kv4 channel complex employs novel alternative mechanisms of closed-state inactivation; (2) the intracellular Zn(2+) site in the T1 domain undergoes a conformational change tightly coupled to voltage-dependent gating and is targeted by nitrosative modulation; and (3) discrete and specific interactions mediate the effects of KChIPs and DPLPs on activation, inactivation and permeation of Kv4 channels. These studies are shedding new light on the molecular bases of I(SA) function and regulation.

  2. Ulnar collateral ligament in the overhead athlete: a current review.

    PubMed

    Dugas, Jeffrey; Chronister, Justin; Cain, E Lyle; Andrews, James R

    2014-09-01

    Ulnar collateral ligament (UCL) injuries are most commonly reported in baseball players (particularly in pitchers) but have also been observed in other overhead athletes including javelin, softball, tennis, volleyball, water polo, and gymnastics. Partial injuries have been successfully treated with appropriate nonoperative measures but complete tears and chronic injuries have shown less benefit from conservative measures. In these cases, surgical reconstruction has become the treatment modality for overhead athlete who wishes to continue to play. This article discusses the functional anatomy and biomechanics of the UCL as related to the pathophysiology of overhead throwing, as well as the important clinical methods needed to make accurate and timely diagnosis. It also gives an updated review of the current clinical outcomes and complications of surgical reconstruction.

  3. Assessment of electromagnetic field levels from surrounding high-tension overhead power lines for proposed land use.

    PubMed

    Al-Bassam, E; Elumalai, A; Khan, A; Al-Awadi, L

    2016-05-01

    The surrounding outdoor environment for new development has a big effect on the indoor quality of life. The main aim of this work was to determine the suitability of the area for building new schools with reference to electromagnetic field (EMF) effects. The specific objective of this study was to detect the safe distance from the EMF posed by the high-tension overhead power lines in the vicinity of the specified area. The measurements were taken for both the electric and magnetic fields in different months in order to detect the highest EMF levels during the peak power load season. EMDEX II with E-probe and EMDEX II with Linda were used for the measurements. These instruments were all calibrated by ENERTECH Company in USA. The EMF associated with high tension transmission lines that surrounded the proposed site has to be below 0.2 μT (Italian EMF regulations are the most suitable regulations for the establishment of schools in Kuwait). The safety clearance distance from the existing 300-kV high-tension power line has been assigned as 200 m and from other existing 132-kV high-tension power line was 50 m. The proposed site with its predefined boundaries has a magnetic field below the Italian EMF regulations for the establishment of new schools.

  4. KV1 and KV3 Potassium Channels Identified at Presynaptic Terminals of the Corticostriatal Synapses in Rat.

    PubMed

    Meneses, David; Vega, Ana V; Torres-Cruz, Francisco Miguel; Barral, Jaime

    2016-01-01

    In the last years it has been increasingly clear that KV-channel activity modulates neurotransmitter release. The subcellular localization and composition of potassium channels are crucial to understanding its influence on neurotransmitter release. To investigate the role of KV in corticostriatal synapses modulation, we combined extracellular recording of population-spike and pharmacological blockage with specific and nonspecific blockers to identify several families of KV channels. We induced paired-pulse facilitation (PPF) and studied the changes in paired-pulse ratio (PPR) before and after the addition of specific KV blockers to determine whether particular KV subtypes were located pre- or postsynaptically. Initially, the presence of KV channels was tested by exposing brain slices to tetraethylammonium or 4-aminopyridine; in both cases we observed a decrease in PPR that was dose dependent. Further experiments with tityustoxin, margatoxin, hongotoxin, agitoxin, dendrotoxin, and BDS-I toxins all rendered a reduction in PPR. In contrast heteropodatoxin and phrixotoxin had no effect. Our results reveal that corticostriatal presynaptic KV channels have a complex stoichiometry, including heterologous combinations KV1.1, KV1.2, KV1.3, and KV1.6 isoforms, as well as KV3.4, but not KV4 channels. The variety of KV channels offers a wide spectrum of possibilities to regulate neurotransmitter release, providing fine-tuning mechanisms to modulate synaptic strength.

  5. KV1 and KV3 Potassium Channels Identified at Presynaptic Terminals of the Corticostriatal Synapses in Rat

    PubMed Central

    Meneses, David; Vega, Ana V.; Torres-Cruz, Francisco Miguel; Barral, Jaime

    2016-01-01

    In the last years it has been increasingly clear that KV-channel activity modulates neurotransmitter release. The subcellular localization and composition of potassium channels are crucial to understanding its influence on neurotransmitter release. To investigate the role of KV in corticostriatal synapses modulation, we combined extracellular recording of population-spike and pharmacological blockage with specific and nonspecific blockers to identify several families of KV channels. We induced paired-pulse facilitation (PPF) and studied the changes in paired-pulse ratio (PPR) before and after the addition of specific KV blockers to determine whether particular KV subtypes were located pre- or postsynaptically. Initially, the presence of KV channels was tested by exposing brain slices to tetraethylammonium or 4-aminopyridine; in both cases we observed a decrease in PPR that was dose dependent. Further experiments with tityustoxin, margatoxin, hongotoxin, agitoxin, dendrotoxin, and BDS-I toxins all rendered a reduction in PPR. In contrast heteropodatoxin and phrixotoxin had no effect. Our results reveal that corticostriatal presynaptic KV channels have a complex stoichiometry, including heterologous combinations KV1.1, KV1.2, KV1.3, and KV1.6 isoforms, as well as KV3.4, but not KV4 channels. The variety of KV channels offers a wide spectrum of possibilities to regulate neurotransmitter release, providing fine-tuning mechanisms to modulate synaptic strength. PMID:27379187

  6. Loss of 115 kV Power

    SciTech Connect

    Smith, J.A.

    2001-08-22

    This report discusses the postulated loss of 115 kV power. Continuous electrical power to Savannah River Plant reactors is necessary to maintain water flow for heat removal and essential monitoring and control. Should power supplied to the plant 115 kV system from offsite be lost, on-site generation is sufficient to maintain all reactors in a safe shutdown mode for an indefinite period. Should on-site generators for the 115 kV grid also be lost, diesel-electric generators within each reactor building are also sufficient to maintain safe shutdown for a finite period. In all cases DC power for necessary monitoring and control would be available from battery systems with AC converter backup.

  7. 18. PRIOR TO THE USE OF CONVEYORS AND OVERHEAD RAILS, ...

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

    18. PRIOR TO THE USE OF CONVEYORS AND OVERHEAD RAILS, MOLDERS, USUALLY AFRICAN-AMERICAN, HAD TO INDIVIDUALLY HAND FILL MOLDS LAID OUT ON THE FLOOR, SUCH AS THESE IN THE MALLEABLE FOUNDRY IN 1923. - Stockham Pipe & Fittings Company, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  8. DEVELOPMENT AND EVALUATION OF A NEW DEVICE FOR OVERHEAD DRILLING

    PubMed Central

    Rempel, David M.; Star, Demetra; Gibbons, Billy; Barr, Alan; Janowitz, Ira

    2008-01-01

    Drilling overhead into concrete is a strenuous task that is associated with shoulder, arm, neck and back musculoskeletal disorders due to the forceful and awkward aspects of the work. This common task is done to hang pipes, ducts and trays and is performed by construction workers in the electrical, pipe fitting, sheet metal, ironwork and carpentry trades. In this project, alternative devices for overhead drilling were developed in order to reduce the high shoulder loads. The design premise for the alternative devices was adopted from interventions developed on construction sites. These devices were evaluated for usability, productivity, and fatigue in two rounds of testing by 30 construction workers performing their usual overhead drilling. After each round of testing the device designs were modified based on feedback. The final design was associated with much less arm fatigue but similar productivity compared to the usual method for overhead drilling. The feedback, design suggestions and field testing by experienced construction workers was vital to the successful development of these devices. Field testing were done with real tasks, in diverse field settings, with subjects familiar with the task. Multiple rounds of field testing and redesign can significantly improve the safety and usability of new tools. Having experienced workers accessing the new tools can help with determining if and how a new tool is compatible and beneficial to current work practices. PMID:19079737

  9. A Simple Polarimeter and Experiments Utilizing an Overhead Projector.

    ERIC Educational Resources Information Center

    Dorn, H. C.; And Others

    1984-01-01

    Although polarimeters that illustrate rotation of plane-polarized light by chiral solutions have been previously described, the polarimeter described in this paper has certain advantages when used in conjunction with an overhead projector. Instructions for constructing this polarimeter and its use in demonstrating the optical activity of sugars…

  10. Phase Sensitive Cueing for 3D Objects in Overhead Images

    SciTech Connect

    Paglieroni, D

    2005-02-04

    Locating specific 3D objects in overhead images is an important problem in many remote sensing applications. 3D objects may contain either one connected component or multiple disconnected components. Solutions must accommodate images acquired with diverse sensors at various times of the day, in various seasons of the year, or under various weather conditions. Moreover, the physical manifestation of a 3D object with fixed physical dimensions in an overhead image is highly dependent on object physical dimensions, object position/orientation, image spatial resolution, and imaging geometry (e.g., obliqueness). This paper describes a two-stage computer-assisted approach for locating 3D objects in overhead images. In the matching stage, the computer matches models of 3D objects to overhead images. The strongest degree of match over all object orientations is computed at each pixel. Unambiguous local maxima in the degree of match as a function of pixel location are then found. In the cueing stage, the computer sorts image thumbnails in descending order of figure-of-merit and presents them to human analysts for visual inspection and interpretation. The figure-of-merit associated with an image thumbnail is computed from the degrees of match to a 3D object model associated with unambiguous local maxima that lie within the thumbnail. This form of computer assistance is invaluable when most of the relevant thumbnails are highly ranked, and the amount of inspection time needed is much less for the highly ranked thumbnails than for images as a whole.

  11. Overhead Projector Spectrum of Polymethine Dye: A Physical Chemistry Demonstration.

    ERIC Educational Resources Information Center

    Solomon, Sally; Hur, Chinhyu

    1995-01-01

    Encourages the incorporation into lecture of live experiments that can be predicted or interpreted with abstract models. A demonstration is described where the position of the predominant peak of 1,1'-diethyl-4,4'-cyanine iodide is measured in class using an overhead projector spectrometer, then predicted using the model of a particle in a…

  12. 12. OVERHEAD VIEW OF THE EVISCERATION AREA; LOOKING NORTH FROM ...

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

    12. OVERHEAD VIEW OF THE EVISCERATION AREA; LOOKING NORTH FROM THE VISITORS' GALLERY; NOTE THE RAISED CONCRETE PLATFORMS FOR WORKERS; VISCERA TABLE HAS BEEN REMOVED - Rath Packing Company, Beef Killing Building, Sycamore Street between Elm & Eighteenth Streets, Waterloo, Black Hawk County, IA

  13. STOCK YARD LOOKING SOUTHEAST SHOWING OVERHEAD YARD CRANE RAIL, THE ...

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

    STOCK YARD LOOKING SOUTHEAST SHOWING OVERHEAD YARD CRANE RAIL, THE MALLEABLE CUPOLAS AND EMISSION RECOVERY SYSTEM, OLD SHED ROOF THAT COVERED THE EARLIER MALLEABLE CUPOLA CHARGING CRANE, MALLEABLE FOUNDRY, AND POLLUTION CONTROL BAGHOUSE. - Stockham Pipe & Fittings Company, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  14. 5. OVERHEAD VIEW OF GENE CAMP LOOKING SOUTH. GENE PUMP ...

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

    5. OVERHEAD VIEW OF GENE CAMP LOOKING SOUTH. GENE PUMP PLANT IS AT CENTER WITH ADMINISTRATIVE COMPLEX IN FOREGROUND AND RESIDENTIAL AREA BEYOND PLANT. - Gene Pump Plant, South of Gene Wash Reservoir, 2 miles west of Whitsett Pump Plant, Parker Dam, San Bernardino County, CA

  15. Dissolving Carboxylic Acids and Primary Amines on the Overhead Projector

    ERIC Educational Resources Information Center

    Solomon, Sally D.; Rutkowsky, Susan A.

    2010-01-01

    Liquid carboxylic acids (or primary amines) with limited solubility in water are dissolved by addition of aqueous sodium hydroxide (or hydrochloric acid) on the stage of an overhead projector using simple glassware and very small quantities of chemicals. This effective and colorful demonstration can be used to accompany discussions of the…

  16. 19. Interior view showing flight simulator partition and rear overhead ...

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

    19. Interior view showing flight simulator partition and rear overhead door, dock no. 493. View to south. - Offutt Air Force Base, Looking Glass Airborne Command Post, Nose Docks, On either side of Hangar Access Apron at Northwest end of Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  17. Swing-out rail system separates overhead crane rails

    NASA Technical Reports Server (NTRS)

    Pitkin, R. G.

    1966-01-01

    Swing-out rail system separates and reconnects the overhead traveling crane rails of a building to provide for the passage of a thick concrete radiation shield sliding door through the rails. In the swing-out position, the rail cantilevered from an axial shaft.

  18. 29 CFR 1926.1438 - Overhead & gantry cranes.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Cranes and Derricks in Construction § 1926.1438... equipment when used in construction and permanently installed in a facility: overhead and gantry cranes, including semigantry, cantilever gantry, wall cranes, storage bridge cranes, and others having the same...

  19. Orbiter View of Curiosity From Nearly Straight Overhead

    NASA Image and Video Library

    2012-08-31

    Details such as the shadow of the mast on NASA Mars rover Curiosity appear in an image taken Aug. 17, 2012, by the HiRISE camera on NASA Mars Reconnaissance Orbiter, from more directly overhead than previous HiRISE images of Curiosity.

  20. 13. Emplacement no. 2, overhead view of counterweight well, showing ...

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

    13. Emplacement no. 2, overhead view of counterweight well, showing channel for gun motor cable and bolt plates upon which base ring of gun carriage was mounted - Fort Wadsworth Battery Romeyn B. Ayers, South side of Ayers Road, Staten Island, Rosebank, Richmond County, NY

  1. Simulation of Centrifugal Forces on an Overhead Projector

    ERIC Educational Resources Information Center

    Buvari, A.

    1977-01-01

    Describes the use of images on an overhead projector to explain concepts like centrifugal force and Cariolis force in such a way that students can realize that they are pseudo-forces, i.e., observations arising only from referring phenomena to an accelerating reference system. (MLH)

  2. A Simple Polarimeter and Experiments Utilizing an Overhead Projector.

    ERIC Educational Resources Information Center

    Dorn, H. C.; And Others

    1984-01-01

    Although polarimeters that illustrate rotation of plane-polarized light by chiral solutions have been previously described, the polarimeter described in this paper has certain advantages when used in conjunction with an overhead projector. Instructions for constructing this polarimeter and its use in demonstrating the optical activity of sugars…

  3. DEVELOPMENT AND EVALUATION OF A NEW DEVICE FOR OVERHEAD DRILLING.

    PubMed

    Rempel, David M; Star, Demetra; Gibbons, Billy; Barr, Alan; Janowitz, Ira

    2007-11-01

    Drilling overhead into concrete is a strenuous task that is associated with shoulder, arm, neck and back musculoskeletal disorders due to the forceful and awkward aspects of the work. This common task is done to hang pipes, ducts and trays and is performed by construction workers in the electrical, pipe fitting, sheet metal, ironwork and carpentry trades. In this project, alternative devices for overhead drilling were developed in order to reduce the high shoulder loads. The design premise for the alternative devices was adopted from interventions developed on construction sites. These devices were evaluated for usability, productivity, and fatigue in two rounds of testing by 30 construction workers performing their usual overhead drilling. After each round of testing the device designs were modified based on feedback. The final design was associated with much less arm fatigue but similar productivity compared to the usual method for overhead drilling. The feedback, design suggestions and field testing by experienced construction workers was vital to the successful development of these devices. Field testing were done with real tasks, in diverse field settings, with subjects familiar with the task. Multiple rounds of field testing and redesign can significantly improve the safety and usability of new tools. Having experienced workers accessing the new tools can help with determining if and how a new tool is compatible and beneficial to current work practices.

  4. The Overhead System: Production, Implementation and Utilization. 2nd Edition.

    ERIC Educational Resources Information Center

    Smith, Richard E.; Pearson, Jerry D.

    This handbook is designed to help three groups: the administrator who does not have the services of a media specialist, the media specialist who wishes to expand his knowledge or skills, and the classroom teacher who recognizes the value of the overhead as a teaching tool and is looking for practical assistance. Guidelines are provided in 11…

  5. GRINDING ROOM, LOOKING EAST. NOTE OVERHEAD BRIDGE CRANE RIDING ON ...

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

    GRINDING ROOM, LOOKING EAST. NOTE OVERHEAD BRIDGE CRANE RIDING ON STEEL RAILS SUPPORTED BY WOODEN BEAMS AND CYCLONE CLASSIFIER IN CENTER. AT RIGHT IS TOP PORTION OF FLASH FLOTATION CELL. - Shenandoah-Dives Mill, 135 County Road 2, Silverton, San Juan County, CO

  6. MOBILE LADLES, ATTACHED TO OVERHEAD RAILS, ARE FILLED AT EITHER ...

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

    MOBILE LADLES, ATTACHED TO OVERHEAD RAILS, ARE FILLED AT EITHER THE MALLEABLE FOUNDRY BULL LADLE OR ELECTRIC FURNACE BEFORE THEY TRANSPORT MOLTEN IRON TO MOLDS PREPARED BY DISAMATIC MOLDMAKING MACHINE OR ON ONE OF THE CONVEYORS. - Stockham Pipe & Fittings Company, Malleable Foundry, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  7. The Overhead Projector and the Teacher of English in Brazil.

    ERIC Educational Resources Information Center

    Funck, Elvio Antonio

    This paper presents arguments for the consistent use of modern audiovisual aids in English classes, not as a complementary device, but as a fundamental aid. The intention of the thesis is to: (1) show that the overhead projector can be used to help students develop the four language skills; and (2) encourage English teachers, particularly in…

  8. Dissolving Carboxylic Acids and Primary Amines on the Overhead Projector

    ERIC Educational Resources Information Center

    Solomon, Sally D.; Rutkowsky, Susan A.

    2010-01-01

    Liquid carboxylic acids (or primary amines) with limited solubility in water are dissolved by addition of aqueous sodium hydroxide (or hydrochloric acid) on the stage of an overhead projector using simple glassware and very small quantities of chemicals. This effective and colorful demonstration can be used to accompany discussions of the…

  9. DETAIL OVERHEAD VIEW OF SECONDARY ORE BIN, CONVEYOR PLATFORM TRAM ...

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

    DETAIL OVERHEAD VIEW OF SECONDARY ORE BIN, CONVEYOR PLATFORM TRAM TRESTLE, AND LOADING PLATFORM, LOOKING SOUTHWEST. THE HOLE IN THE ORE BIN FLOOR CAN BE SEEN, AND BALL MILL FOUNDATION AT LOWER LEFT CORNER. SEE CA-291-13 FOR IDENTICAL B&W NEGATIVE. - Keane Wonder Mine, Park Route 4 (Daylight Pass Cutoff), Death Valley Junction, Inyo County, CA

  10. View, from south showing verticals, diagonals, and overhead bracing of ...

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

    View, from south showing verticals, diagonals, and overhead bracing of south span Pratt through trusses, south portal of north span, pipe rails and posts, and concrete deck with bituminous wearing surface - Castle Garden Bridge, Township Route 343 over Bennetts Branch of Sinnemahoning Creek, Driftwood, Cameron County, PA

  11. Oblique view to the northwest detailing four overhead rolling doors ...

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

    Oblique view to the northwest detailing four overhead rolling doors on the northeast elevation - Over-the-Horizon Backscatter Radar Network, Mountain Home Air Force Operations Building, On Desert Street at 9th Avenue Mountain Home Air Force Base, Mountain Home, Elmore County, ID

  12. Overhead Projector Demonstrations: Some Ideas from the Past.

    ERIC Educational Resources Information Center

    Kolb, Doris

    1987-01-01

    Describes nine chemistry demonstrations that can be done using an overhead projector. Includes demonstrations on common ion effect, crystal formation from supersaturated solutions, making iron positive with nitric acid, optical activity, carbon dioxide in human breath, amphoteric hydroxides, the surface tension of mercury, and natural acid-base…

  13. 13. Interior view, grain tanks (bins). Barrel view of overhead ...

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

    13. Interior view, grain tanks (bins). Barrel view of overhead (fill) conveyor gallery bridge extending through tops of tanks just below roofs. Grain tripper straddles belt conveyor at mid-view. - Saint Anthony Elevator No. 3, 620 Malcom Avenue, Southeast, Minneapolis, Hennepin County, MN

  14. 5. Overhead trackandpulley system used to haul materials stored in ...

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

    5. Overhead track-and-pulley system used to haul materials stored in stock bins under Jones Street to the Tender Frame Shop. - Central of Georgia Railway, Savannah Repair Shops & Terminal Facilities, Tender Frame Shop, Bounded by West Broad, Jones, West Boundary & Hull Streets, Savannah, Chatham County, GA

  15. Communication overhead on the Intel iPSC-860 hypercube

    NASA Technical Reports Server (NTRS)

    Bokhari, Shahid H.

    1990-01-01

    Experiments were conducted on the Intel iPSC-860 hypercube in order to evaluate the overhead of interprocessor communication. It is demonstrated that: (1) contrary to popular belief, the distance between two communicating processors has a significant impact on communication time, (2) edge contention can increase communication time by a factor of more than 7, and (3) node contention has no measurable impact.

  16. Prevalence of Scapular Dyskinesis in Overhead and Nonoverhead Athletes

    PubMed Central

    Burn, Matthew B.; McCulloch, Patrick C.; Lintner, David M.; Liberman, Shari R.; Harris, Joshua D.

    2016-01-01

    Background: Scapular dyskinesis, or abnormal dynamic scapular control, is a condition that is commonly associated with shoulder pathology but is also present in asymptomatic individuals. Literature varies on whether it represents a cause or symptom of shoulder pathology, but it is believed to be a risk factor for further injury. Clinical identification focuses on visual observation and examination maneuvers. Treatment of altered scapular motion has been shown to improve shoulder symptoms. It is thought to be more common in overhead athletes due to their reliance on unilateral upper extremity function but the incidence within nonoverhead athletes is unknown. Hypothesis: Overhead athletes will have a greater prevalence of scapular dyskinesis when compared with nonoverhead athletes. Study Design: Systematic review; Level of evidence, 3. Methods: After PROSPERO registration, a systematic review was performed using PRISMA guidelines through the PubMed database looking for studies published before October 2014. All studies containing the search terms scapular, scapulothoracic, dyskinesis, dyskinesia, shoulder athlete, or overhead athlete were included. Studies that did not include prevalence data for scapular dyskinesis were excluded. Study methodological quality was evaluated using the modified Coleman methodology score. Descriptive statistics and 2-proportion 2-tailed z-tests were used to compare the reported prevalence of scapular dyskinesis between overhead and nonoverhead athletes. Results: Twelve studies were analyzed including 1401 athletes (1257 overhead and 144 nonoverhead; mean age, 24.4 ± 7.1 years; 78% men). All the studies were evidence level 2 (33%) or level 3 (67%). The reported prevalence of scapular dyskinesis was significantly (P < .0001) higher in overhead athletes (61%) compared with nonoverhead athletes (33%). Conclusion: Scapular dyskinesis was found to have a greater reported prevalence (61%) in overhead athletes compared with nonoverhead athletes

  17. Kv1.1 and Kv1.2: similar channels, different seizure models.

    PubMed

    Robbins, Carol A; Tempel, Bruce L

    2012-06-01

    Voltage-gated K(+) channels (Kv) represent the largest family of genes in the K(+) channel family. The Kv1 subfamily plays an essential role in the initiation and shaping of action potentials, influencing action potential firing patterns and controlling neuronal excitability. Overlapping patterns with differential expression and precise localization of Kv1.1 and Kv1.2 channels targeted to specialized subcellular compartments contribute to distinctive patterns of neuronal excitability. Dynamic regulation of the components in these subcellular domains help to finely tune the cellular and regional networks. Disruption of the expression, distribution, and density of these channels through deletion or mutation of the genes encoding these channels, Kcna1 and Kcna2, is associated with neurologic pathologies including epilepsy and ataxia in humans and in rodent models. Kv1.1 and Kv1.2 knockout mice both have seizures beginning early in development; however, each express a different seizure type (pathway), although the channels are from the same subfamily and are abundantly coexpressed. Voltage-gated ion channels clustered in specific locations may present a novel therapeutic target for influencing excitability in neurologic disorders associated with some channelopathies. Wiley Periodicals, Inc. © 2012 International League Against Epilepsy.

  18. Moeglichkeiten individualisierter Arbeit mit Hilfe des Overhead-Projektors (Possibilities for Individualized Work with the Aid of the Overhead Projector)

    ERIC Educational Resources Information Center

    Budde, Ulrich

    1975-01-01

    Individualized work in teaching English is highly desirable, and the overhead projector is particularly useful in such work. Three examples of its possibilities are given: Dialog treatment, working with basic ("kernel") texts, and comparison of the simple present, simple past and present perfect tenses. (Text is in German.) (IFS/WGA)

  19. Living near overhead high voltage transmission power lines as a risk factor for childhood acute lymphoblastic leukemia: a case-control study.

    PubMed

    Sohrabi, Mohammad-Reza; Tarjoman, Termeh; Abadi, Alireza; Yavari, Parvin

    2010-01-01

    This study aimed to investigate association of living near high voltage power lines with occurrence of childhood acute lymphoblastic leukemia (ALL). Through a case-control study 300 children aged 1-18 years with confirmed ALL were selected from all referral teaching centers for cancer. They interviewed for history of living near overhead high voltage power lines during at least past two years and compared with 300 controls which were individually matched for sex and approximate age. Logistic regression, chi square and paired t-tests were used for analysis when appropriate. The case group were living significantly closer to power lines (P<0.001). More than half of the cases were exposed to two or three types of power lines (P<0.02). Using logistic regression, odds ratio of 2.61 (95%CI: 1.73 to 3.94) calculated for less than 600 meters far from the nearest lines against more than 600 meters. This ratio estimated as 9.93 (95%CI: 3.47 to 28.5) for 123 KV, 10.78 (95%CI: 3.75 to 31) for 230 KV and 2.98 (95%CI: 0.93 to 9.54) for 400 KV lines. Odds of ALL decreased 0.61 for every 600 meters from the nearest power line. This study emphasizes that living close to high voltage power lines is a risk for ALL.

  20. Dihydropyridine Ca2+ channel antagonists and agonists block Kv4.2, Kv4.3 and Kv1.4 K+ channels expressed in HEK293 cells.

    PubMed

    Hatano, Noriyuki; Ohya, Susumu; Muraki, Katsuhiko; Giles, Wayne; Imaizumi, Yuji

    2003-06-01

    (1) We have determined the molecular basis of nicardipine-induced block of cardiac transient outward K(+) currents (I(to)). Inhibition of I(to) was studied using cloned voltage-dependent K(+) channels (Kv) channels, rat Kv4.3L, Kv4.2, and Kv1.4, expressed in human embryonic kidney cell line 293 (HEK293) cells. (2) Application of the dihydropyridine Ca(2+) channel antagonist, nicardipine, accelerated the inactivation rate and reduced the peak amplitude of Kv4.3L currents in a concentration-dependent manner (IC(50): 0.42 micro M). The dihydropyridine (DHP) Ca(2+) channel agonist, Bay K 8644, also blocked this K(+) current (IC(50): 1.74 micro M). (3) Nicardipine (1 micro M) slightly, but significantly, shifted the voltage dependence of activation and steady-state inactivation to more negative potentials, and also slowed markedly the recovery from inactivation of Kv4.3L currents. (4) Coexpression of K(+) channel-interacting protein 2 (KChIP2) significantly slowed the inactivation of Kv4.3L currents as expected. However, the features of DHP-induced block of K(+) current were not substantially altered. (5) Nicardipine exhibited similar block of Kv1.4 and Kv4.2 channels stably expressed in HEK293 cells; IC(50)'s were 0.80 and 0.62 micro M, respectively. (6) Thus, at submicromolar concentrations, DHP Ca(2+) antagonist and agonist inhibit Kv4.3L and have similar inhibiting effects on other components of cardiac I(to), Kv4.2 and Kv1.4.

  1. A Kv1.5 to Kv1.3 switch in endogenous hippocampal microglia and a role in proliferation.

    PubMed

    Kotecha, S A; Schlichter, L C

    1999-12-15

    The proliferation of microglia is a normal process in CNS development and in the defense against pathological insults, although, paradoxically, it contributes to several brain diseases. We have examined the types of voltage-activated K(+) currents (Kv) and their roles in microglial proliferation. Microglia were tissue-printed directly from the hippocampal region using brain slices from 5- to 14-d-old rats. Immediately after tissue prints were prepared, unipolar and bipolar microglia expressed a large Kv current, and the cells were not proliferating. Surprisingly, this current was biophysically and pharmacologically distinct from Kv1.3, which has been found in dissociated, cultured microglia, but it was very similar to Kv1.5. After several days in culture the microglia became highly proliferative, and although the Kv prevalence and current density decreased, many cells exhibited a prominent Kv that was indistinguishable from Kv1.3. The Kv1.5-like current was present in nonproliferating cells, whereas proliferating cells expressed the Kv1.3-like current. Immunocytochemical staining showed a dramatic shift in expression and localization of Kv1.3 and Kv1.5 proteins in microglia: Kv1.5 moving away from the surface and Kv1.3 moving to the surface as the cells were cultured. K(+) channel blockers inhibited proliferation, and the pharmacology of this inhibition correlated with the type of Kv current expressed. Our study, which introduces a method for the physiological examination of microglia from identified brain regions, demonstrates the differential expression of two functional Kv subunits and shows that a functional delayed rectifier current is necessary for microglia proliferation.

  2. Ten Suggestions and One Commandment: Using Overhead Projectors in Geography Classrooms.

    ERIC Educational Resources Information Center

    Gersmehl, Philip J.

    1985-01-01

    Suggestions for effective use of overhead projectors include making images large, preparing standard base maps, making lettering clear, presenting only one idea per overhead, keeping things simple, using only half a page for each image, using the overhead as a chalkboard, using color thoughtfully, making symbols bold, and anticipating emergencies.…

  3. 30 CFR 56.16015 - Work or travel on overhead crane bridges.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Work or travel on overhead crane bridges. 56... Materials Storage and Handling § 56.16015 Work or travel on overhead crane bridges. No person shall work from or travel on the bridge of an overhead crane unless the bridge is provided with substantial...

  4. 30 CFR 57.16015 - Work or travel on overhead crane bridges.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Work or travel on overhead crane bridges. 57... MINES Materials Storage and Handling § 57.16015 Work or travel on overhead crane bridges. No person shall work from or travel on the bridge of an overhead crane unless the bridge is provided with...

  5. 30 CFR 56.16015 - Work or travel on overhead crane bridges.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Work or travel on overhead crane bridges. 56... Materials Storage and Handling § 56.16015 Work or travel on overhead crane bridges. No person shall work from or travel on the bridge of an overhead crane unless the bridge is provided with substantial...

  6. 30 CFR 57.16015 - Work or travel on overhead crane bridges.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Work or travel on overhead crane bridges. 57... MINES Materials Storage and Handling § 57.16015 Work or travel on overhead crane bridges. No person shall work from or travel on the bridge of an overhead crane unless the bridge is provided with...

  7. 30 CFR 56.16015 - Work or travel on overhead crane bridges.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Work or travel on overhead crane bridges. 56... Materials Storage and Handling § 56.16015 Work or travel on overhead crane bridges. No person shall work from or travel on the bridge of an overhead crane unless the bridge is provided with substantial...

  8. 30 CFR 57.16015 - Work or travel on overhead crane bridges.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Work or travel on overhead crane bridges. 57... MINES Materials Storage and Handling § 57.16015 Work or travel on overhead crane bridges. No person shall work from or travel on the bridge of an overhead crane unless the bridge is provided with...

  9. 30 CFR 56.16015 - Work or travel on overhead crane bridges.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Work or travel on overhead crane bridges. 56... Materials Storage and Handling § 56.16015 Work or travel on overhead crane bridges. No person shall work from or travel on the bridge of an overhead crane unless the bridge is provided with substantial...

  10. 30 CFR 57.16015 - Work or travel on overhead crane bridges.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Work or travel on overhead crane bridges. 57... MINES Materials Storage and Handling § 57.16015 Work or travel on overhead crane bridges. No person shall work from or travel on the bridge of an overhead crane unless the bridge is provided with...

  11. 30 CFR 57.16015 - Work or travel on overhead crane bridges.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Work or travel on overhead crane bridges. 57... MINES Materials Storage and Handling § 57.16015 Work or travel on overhead crane bridges. No person shall work from or travel on the bridge of an overhead crane unless the bridge is provided with...

  12. 30 CFR 56.16015 - Work or travel on overhead crane bridges.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Work or travel on overhead crane bridges. 56... Materials Storage and Handling § 56.16015 Work or travel on overhead crane bridges. No person shall work from or travel on the bridge of an overhead crane unless the bridge is provided with substantial...

  13. Electromyographic analysis of an ergonomic risk factor: overhead work.

    PubMed

    Kinali, Gulsah; Kara, Sadık; Yıldırım, Mustafa Selman

    2016-06-01

    [Purpose] Repetitive upper extremity exercises result in overuse injuries. However, it is challenging to identify the specific causative movements. This study evaluated the effects of different shoulder positions on grip and electrophysiological activity of upper extremity muscles. [Subjects and Methods] Forty subjects ranging from 18 and 30 years of age were analyzed. Surface electromyography and hand grip strength were measured during a range of shoulder exercises and numerous signal processing methods were applied. [Results] The maximum electromyographic activity intensity was observed in the wrist extensors at various angles. Deltoid activity rose significantly during shoulder flexion. [Conclusion] Overhead work causes shoulder muscle fatigue and prevents effective hand function, which affects occupational health and efficiency. Overhead work involves a hazardous position and decreases efficiency. Ergonomic solutions should be developed to prevent muscle fatigue and decreased grip force.

  14. Electromyographic analysis of an ergonomic risk factor: overhead work

    PubMed Central

    Kinali, Gulsah; Kara, Sadık; Yıldırım, Mustafa Selman

    2016-01-01

    [Purpose] Repetitive upper extremity exercises result in overuse injuries. However, it is challenging to identify the specific causative movements. This study evaluated the effects of different shoulder positions on grip and electrophysiological activity of upper extremity muscles. [Subjects and Methods] Forty subjects ranging from 18 and 30 years of age were analyzed. Surface electromyography and hand grip strength were measured during a range of shoulder exercises and numerous signal processing methods were applied. [Results] The maximum electromyographic activity intensity was observed in the wrist extensors at various angles. Deltoid activity rose significantly during shoulder flexion. [Conclusion] Overhead work causes shoulder muscle fatigue and prevents effective hand function, which affects occupational health and efficiency. Overhead work involves a hazardous position and decreases efficiency. Ergonomic solutions should be developed to prevent muscle fatigue and decreased grip force. PMID:27390448

  15. On-line corrosion control in refinery overhead systems

    SciTech Connect

    Correa, L.A.

    1995-11-01

    Corrosion is one of the great causes of accidents and economic losses in petroleum and petrochemical industries. Crude unit overheads are one of the most corrosion affected parts and large amounts of work and money has been spent on its control and prevention. Thus, new materials, inhibitors and monitoring techniques are constantly under testing in order to improve corrosion prevention and plant reliability. Expert Systems are a rising technology in industrial process monitoring and problem diagnosing. This sort of computer program is developed trying to simulate the human expert intelligent behavior in the task of solving a specific problem. The crude units overhead corrosion control is a hard and time consuming task that seems to be a fruitful field to expert systems application.

  16. Reducing the overhead for quantum computation when noise is biased

    NASA Astrophysics Data System (ADS)

    Webster, Paul; Bartlett, Stephen D.; Poulin, David

    2015-12-01

    We analyze a model for fault-tolerant quantum computation with low overhead suitable for situations where the noise is biased. The basis for this scheme is a gadget for the fault-tolerant preparation of magic states that enable universal fault-tolerant quantum computation using only Clifford gates that preserve the noise bias. We analyze the distillation of |T > -type magic states using this gadget at the physical level, followed by concatenation with the 15-qubit quantum Reed-Muller code, and comparing our results with standard constructions. In the regime where the noise bias (rate of Pauli Z errors relative to other single-qubit errors) is greater than a factor of 10, our scheme has lower overhead across a broad range of relevant noise rates.

  17. MICROINSTABILITY OF THE SHOULDER IN THE OVERHEAD ATHLETE

    PubMed Central

    Curtis, Alan S.

    2013-01-01

    The overhead throwing athlete is an extremely challenging patient in sports medicine. The repetitive microtraumatic stresses and extreme ranges of motion observed within the athlete’s shoulder joint complex during the throwing motion constantly place the athlete at risk for injury. While gross instability of the shoulder is possible, microinstability is seen far more frequently and is associated with a variety of different pathologies, including rotator cuff tendonitis, internal impingement, and labral lesions. Treatment of the overhead athlete requires the understanding of several principles based on the unique physical characteristics of this type of athlete and the demands placed upon the static stabilizing structures during the act of throwing. The purpose of this paper is to describe these principles and incorporate them into in a multi‐phase progressive rehabilitation program designed to prevent injuries and rehabilitate the injured athlete, both non‐operatively and postoperatively. PMID:24175140

  18. Limiting electric fields of HVDC overhead power lines.

    PubMed

    Leitgeb, N

    2014-05-01

    As a consequence of the increased use of renewable energy and the now long distances between energy generation and consumption, in Europe, electric power transfer by high-voltage (HV) direct current (DC) overhead power lines gains increasing importance. Thousands of kilometers of them are going to be built within the next years. However, existing guidelines and regulations do not yet contain recommendations to limit static electric fields, which are one of the most important criteria for HVDC overhead power lines in terms of tower design, span width and ground clearance. Based on theoretical and experimental data, in this article, static electric fields associated with adverse health effects are analysed and various criteria are derived for limiting static electric field strengths.

  19. 4. Overhead view showing the 1927 bridge (narrow bridgeleft side) ...

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

    4. Overhead view showing the 1927 bridge (narrow bridge-left side) and 1959 bridge (right side) across Carquinez Strait. Town of Crockett is on south bank (bottom of image). C&H sugar factory is along the strait to the east (right) side of the 1959 bridge. The toll plaza is at the top of the image on the 1959 bridge side. - Carquinez Bridge, Spanning Carquinez Strait at Interstate 80, Vallejo, Solano County, CA

  20. Glutinous Water. Protecting Vertical and Overhead Surfaces from Fire Spread

    DTIC Science & Technology

    1994-02-28

    DISTRIBUTION CODE Approved for public release; distribution unlimited. 13. ABSTRACT (Maximum 200 words ) Most of the water used in firefighting is not only...Naval Research Laboratory AD-A277 280 Washington, DC 20375-5320 NRL/MR/6180--94-7431 DTIC S ELECTE MAR 24 19941 Glutinous Water F Protecting Vertical...TYPE AND DATES COVERED February 28, 1994 4. TITLE AND SUBTITLE 5. FUNDING NUMBERS Glutinous Water Protecting Vertical and Overhead Surfaces From Fire

  1. Overhead-Performance Tradeoffs in Distributed Wireless Networks

    DTIC Science & Technology

    2015-06-26

    comparison, we have included a trendline for the rate distortion function plus a bit. Key Publications & Abstracts • B. D. Boyle , J. M. Walsh, and S. Weber...IID. • Jie Ren, Bradford Boyle , Gwanmo Ku, Steven Weber, John MacLaren Walsh, Overhead Performance Tradeoffs A Resource Allocation Perspective, IEEE...Bradford D. Boyle , Jie Ren, John MacLaren Walsh, and Steven Weber, Interactive Scalar Quantization for Distributed Extremization, IEEE Trans. Signal

  2. Passive optical sensor for lightning detection on overhead power lines

    NASA Astrophysics Data System (ADS)

    Rosolem, J. B.; Barbosa, C. F.; Florídia, C.; Bezerra, E. L.

    2009-10-01

    In this work we present the results of a passive optical sensor for monitoring lightning strikes on overhead power lines, which can also be used for several other applications. The optic sensor is very simple and cheap and basically consists in the use of an antenna connected directly to a semiconductor laser. No batteries and solar panels are necessary to implement this sensing system in power lines towers. It was tested in laboratory and showed a good performance.

  3. An estimation of lightning insulation level of overhead distribution lines

    SciTech Connect

    Jacob, P.B.; Grzybowski, S. . Dept. of Electrical Engineering); Ross, E.R. )

    1991-01-01

    This paper develops a practical procedure for determining the total insulation strength of multiple or composite insulations most commonly used in the design of overhead distribution lines. Laboratory test data were obtained on a wide range of combinations and configurations utilizing porcelain, polymer and fiberglass insulators as well as wood poles and wood crossarms. Data were obtained for both dry and wet conditions with positive and negative polarities of the impulses.

  4. Contract Overhead Reduction Across the Department of Defense

    DTIC Science & Technology

    2016-02-16

    strategy, a business adds a portion or representative share of overhead costs to the sales price of items or overall price of services in order to...exceeding specified standards or goals.”5 There are two broad category types of contracts – fixed price and cost reimbursement contracts. In the first...category, in the cases of a product having stable build characteristics, well-known supply chains, or a longer history of product pricing , then the

  5. Modeling the Virtual Machine Launching Overhead under Fermicloud

    SciTech Connect

    Garzoglio, Gabriele; Wu, Hao; Ren, Shangping; Timm, Steven; Bernabeu, Gerard; Noh, Seo-Young

    2014-11-12

    FermiCloud is a private cloud developed by the Fermi National Accelerator Laboratory for scientific workflows. The Cloud Bursting module of the FermiCloud enables the FermiCloud, when more computational resources are needed, to automatically launch virtual machines to available resources such as public clouds. One of the main challenges in developing the cloud bursting module is to decide when and where to launch a VM so that all resources are most effectively and efficiently utilized and the system performance is optimized. However, based on FermiCloud’s system operational data, the VM launching overhead is not a constant. It varies with physical resource (CPU, memory, I/O device) utilization at the time when a VM is launched. Hence, to make judicious decisions as to when and where a VM should be launched, a VM launch overhead reference model is needed. The paper is to develop a VM launch overhead reference model based on operational data we have obtained on FermiCloud and uses the reference model to guide the cloud bursting process.

  6. Life cycle assessment of overhead and underground primary power distribution.

    PubMed

    Bumby, Sarah; Druzhinina, Ekaterina; Feraldi, Rebe; Werthmann, Danae; Geyer, Roland; Sahl, Jack

    2010-07-15

    Electrical power can be distributed in overhead or underground systems, both of which generate a variety of environmental impacts at all stages of their life cycles. While there is considerable literature discussing the trade-offs between both systems in terms of aesthetics, safety, cost, and reliability, environmental assessments are relatively rare and limited to power cable production and end-of-life management. This paper assesses environmental impacts from overhead and underground medium voltage power distribution systems as they are currently built and managed by Southern California Edison (SCE). It uses process-based life cycle assessment (LCA) according to ISO 14044 (2006) and SCE-specific primary data to the extent possible. Potential environmental impacts have been calculated using a wide range of midpoint indicators, and robustness of the results has been investigated through sensitivity analysis of the most uncertain and potentially significant parameters. The studied underground system has higher environmental impacts in all indicators and for all parameter values, mostly due to its higher material intensity. For both systems and all indicators the majority of impact occurs during cable production. Promising strategies for impact reduction are thus cable failure rate reduction for overhead and cable lifetime extension for underground systems.

  7. Functional characterization of Kv channel beta-subunits from rat brain.

    PubMed Central

    Heinemann, S H; Rettig, J; Graack, H R; Pongs, O

    1996-01-01

    1. The potassium channel beta-subunit from rat brain, Kv beta 1.1, is known to induce inactivation of the delayed rectifier channel Kv1.1 and Kv1.4 delta 1-110. 2. Kv beta 1.1 was co-expressed in Xenopus oocytes with various other potassium channel alpha-subunits. Kv beta 1.1 induced inactivation in members of the Kv1 subfamily with the exception of Kv 1.6; no inactivation of Kv 2.1, Kv 3.4 delta 2-28 and Kv4.1 channels could be observed. 3. The second member of the beta-subunit subfamily, Kv beta 2, had a shorter N-terminal end, accelerated inactivation of the A-type channel Kv 1.4, but did not induce inactivation when co-expressed with delayed rectifiers of the Kv1 channel family. 4. To test whether this subunit co-assembles with Kv alpha-subunits, the N-terminal inactivating domains of Kv beta 1.1 and Kv beta 3 were spliced to the N-terminus of Kv beta 2. The chimaeric beta-subunits (beta 1/ beta 2 and beta 3/ beta 2) induced fast inactivation of several Kv1 channels, indicating that Kv beta 2 associates with these alpha-subunits. No inactivation was induced in Kv 1.3, Kv 1.6, Kv2.1 and Kv3.4 delta 2-28 channels. 5. Kv beta 2 caused a voltage shift in the activation threshold of Kv1.5 of about -10 mV, indicating a putative physiological role. Kv beta 2 had a smaller effect on Kv 1.1 channels. 6. Kv beta 2 accelerated the activation time course of Kv1.5 but had no marked effect on channel deactivation. PMID:8799886

  8. Functional characterization of Kv channel beta-subunits from rat brain.

    PubMed

    Heinemann, S H; Rettig, J; Graack, H R; Pongs, O

    1996-06-15

    1. The potassium channel beta-subunit from rat brain, Kv beta 1.1, is known to induce inactivation of the delayed rectifier channel Kv1.1 and Kv1.4 delta 1-110. 2. Kv beta 1.1 was co-expressed in Xenopus oocytes with various other potassium channel alpha-subunits. Kv beta 1.1 induced inactivation in members of the Kv1 subfamily with the exception of Kv 1.6; no inactivation of Kv 2.1, Kv 3.4 delta 2-28 and Kv4.1 channels could be observed. 3. The second member of the beta-subunit subfamily, Kv beta 2, had a shorter N-terminal end, accelerated inactivation of the A-type channel Kv 1.4, but did not induce inactivation when co-expressed with delayed rectifiers of the Kv1 channel family. 4. To test whether this subunit co-assembles with Kv alpha-subunits, the N-terminal inactivating domains of Kv beta 1.1 and Kv beta 3 were spliced to the N-terminus of Kv beta 2. The chimaeric beta-subunits (beta 1/ beta 2 and beta 3/ beta 2) induced fast inactivation of several Kv1 channels, indicating that Kv beta 2 associates with these alpha-subunits. No inactivation was induced in Kv 1.3, Kv 1.6, Kv2.1 and Kv3.4 delta 2-28 channels. 5. Kv beta 2 caused a voltage shift in the activation threshold of Kv1.5 of about -10 mV, indicating a putative physiological role. Kv beta 2 had a smaller effect on Kv 1.1 channels. 6. Kv beta 2 accelerated the activation time course of Kv1.5 but had no marked effect on channel deactivation.

  9. Open channel block of A-type, kv4.3, and delayed rectifier K+ channels, Kv1.3 and Kv3.1, by sibutramine.

    PubMed

    Kim, Sung Eun; Ahn, Hye Sook; Choi, Bok Hee; Jang, Hyun-Jong; Kim, Myung-Jun; Rhie, Duck-Joo; Yoon, Shin-Hee; Jo, Yang-Hyeok; Kim, Myung-Suk; Sung, Ki-Wug; Hahn, Sang June

    2007-05-01

    The effects of sibutramine on voltage-gated K+ channel (Kv)4.3, Kv1.3, and Kv3.1, stably expressed in Chinese hamster ovary cells, were investigated using the whole-cell patch-clamp technique. Sibutramine did not significantly decrease the peak Kv4.3 currents, but it accelerated the rate of decay of current inactivation in a concentration-dependent manner. This phenomenon was effectively characterized by integrating the total current over the duration of a depolarizing pulse to +40 mV. The IC50 value for the sibutramine block of Kv4.3 was 17.3 microM. Under control conditions, the inactivation of Kv4.3 currents could be fit to a biexponential function, and the time constants for the fast and slow components were significantly decreased after the application of sibutramine. The association (k+1) and dissociation (k-1) rate constants for the sibutramine block of Kv 4.3 were 1.51 microM-1s-1 and 27.35 s-1, respectively. The theoretical KD value, derived from k-1/k+1, yielded a value of 18.11 microM. The block of Kv4.3 by sibutramine displayed a weak voltage dependence, increasing at more positive potentials, and it was use-dependent at 2 Hz. Sibutramine did not affect the time course for the deactivating tail currents. Neither steady-state activation and inactivation nor the recovery from inactivation was affected by sibutramine. Sibutramine caused the concentration-dependent block of the Kv1.3 and Kv3.1 currents with an IC50 value of 3.7 and 32.7 microM, respectively. In addition, sibutramine reduced the tail current amplitude and slowed the deactivation of the tail currents of Kv1.3 and Kv3.1, resulting in a crossover phenomenon. These results indicate that sibutramine acts on Kv4.3, Kv1.3, and Kv3.1 as an open channel blocker.

  10. Subunit composition of Kv1 channels in human CNS.

    PubMed

    Coleman, S K; Newcombe, J; Pryke, J; Dolly, J O

    1999-08-01

    The alpha subunits of Shaker-related K+ channels (Kv1.X) show characteristic distributions in mammalian brain and restricted coassembly. Despite the functional importance of these voltage-sensitive K+ channels and involvement in a number of diseases, little progress has been achieved in deciphering the subunit composition of the (alpha)4(beta)4 oligomers occurring in human CNS. Thus, the association of alpha and beta subunits was investigated in cerebral grey and white matter and spinal cord from autopsy samples. Immunoblotting established the presence of Kv1.1, 1.2, and 1.4 in all the tissues, with varying abundance. Sequential immunoprecipitations identified the subunits coassembled. A putative tetramer of Kv1.3/1.4/1.1/1.2 was found in grey matter. Both cerebral white matter and spinal cord contained the heterooligomers Kv1.1/1.4 and Kv1.1/1.2, similar to grey matter, but both lacked Kv1.3 and the Kv1.4/1.2 combination. An apparent Kv1.4 homooligomer was detected in all the samples, whereas only the brain tissue possessed a putative Kv1.2 homomer. In grey matter, Kvbeta2.1 was coassociated with the Kv1.1/1.2 combination and Kv1.2 homooligomer. In white matter, Kvbeta2.1 was associated with Kv1.2 only, whereas Kvbeta1.1 coprecipitated with all the alpha subunits present. This represents the first description of Kv1 subunit complexes in the human CNS and demonstrates regional variations, indicative of functional specialisation.

  11. Inhibition of Kv4.3 potassium channels by trazodone.

    PubMed

    Chae, Yun Ju; Choi, Jin-Sung; Hahn, Sang June

    2013-08-01

    Trazodone, a triazolopyridine antidepressant, is commonly used in the treatment of depression and insomnia. Kv4.3 channels are transiently, and rapidly, inactivating Kv channels that are highly expressed in cardiac myocytes and neurons. To determine the electrophysiological basis for the cardiac and neuronal actions of trazodone, we studied the effects of trazodone on Kv4.3 currents stably expressed in Chinese hamster ovary cells using the whole-cell patch-clamp technique. Trazodone decreased the peak amplitude of Kv4.3 in a concentration-dependent manner with an IC50 of 55.4 μM. Under control conditions, the time course of inactivation of Kv4.3 at +40 mV was fitted to a double exponential function. Trazodone produced a concentration-dependent slowing of the fast and slow components of Kv4.3 inactivation during a voltage step to +40 mV. The inhibition of Kv4.3 by trazodone was voltage independent over the entire voltage range tested. Trazodone shifted the voltage dependence of the steady-state inactivation of Kv4.3 to a hyperpolarizing direction. However, the slope factor of the steady-state inactivation was not affected by trazodone. Under control conditions, the closed-state inactivation of Kv4.3 was fitted to a single exponential function. Trazodone significantly accelerated the closed-state inactivation of Kv4.3. Trazodone produced a weak use-dependent inhibition of Kv4.3 at frequencies of 1 and 2 Hz. m-Chlorophenylpiperazine (m-CPP), a major metabolite of trazodone, inhibited Kv4.3 less potently than trazodone, with an IC50 of 118.6 μM. These results suggest that trazodone preferentially inhibited Kv4.3 by both binding to the closed state and accelerating the closed-state inactivation of the channel.

  12. Modulation of Closed-State Inactivation in Kv2.1/Kv6.4 Heterotetramers as Mechanism for 4-AP Induced Potentiation.

    PubMed

    Stas, Jeroen I; Bocksteins, Elke; Labro, Alain J; Snyders, Dirk J

    2015-01-01

    The voltage-gated K+ (Kv) channel subunits Kv2.1 and Kv2.2 are expressed in almost every tissue. The diversity of Kv2 current is increased by interacting with the electrically silent Kv (KvS) subunits Kv5-Kv6 and Kv8-Kv9, into functional heterotetrameric Kv2/KvS channels. These Kv2/KvS channels possess unique biophysical properties and display a more tissue-specific expression pattern, making them more desirable pharmacological and therapeutic targets. However, little is known about the pharmacological properties of these heterotetrameric complexes. We demonstrate that Kv5.1, Kv8.1 and Kv9.3 currents were inhibited differently by the channel blocker 4-aminopyridine (4-AP) compared to Kv2.1 homotetramers. In contrast, Kv6.4 currents were potentiated by 4-AP while displaying moderately increased affinities for the channel pore blockers quinidine and flecainide. We found that the 4-AP induced potentiation of Kv6.4 currents was caused by modulation of the Kv6.4-mediated closed-state inactivation: suppression by 4-AP of the Kv2.1/Kv6.4 closed-state inactivation recovered a population of Kv2.1/Kv6.4 channels that was inactivated at resting conditions, i.e. at a holding potential of -80 mV. This modulation also resulted in a slower initiation and faster recovery from closed-state inactivation. Using chimeric substitutions between Kv6.4 and Kv9.3 subunits, we demonstrated that the lower half of the S6 domain (S6c) plays a crucial role in the 4-AP induced potentiation. These results demonstrate that KvS subunits modify the pharmacological response of Kv2 subunits when assembled in heterotetramers and illustrate the potential of KvS subunits to provide unique pharmacological properties to the heterotetramers, as is the case for 4-AP on Kv2.1/Kv6.4 channels.

  13. Visual experience regulates Kv3.1b and Kv3.2 expression in developing rat visual cortex.

    PubMed

    Grabert, J; Wahle, P

    2009-01-23

    Among the GABAergic neocortical interneurons, parvalbumin-containing fast-spiking (FS) basket cells are essential mediators of feed-forward inhibition, network synchrony and oscillations, and timing of the critical period for sensory plasticity. The FS phenotype matures after birth. It depends on the expression of the voltage-gated potassium channels Kv3.1b/3.2 which mediate the fast membrane repolarization necessary for firing fast action potentials at high frequencies. We have now tested in rat visual cortex if visual deprivation affects the Kv3 expression. During normal development, Kv3.1b/3.2 mRNA and protein expression increased in rat visual cortex reaching adult levels around P20. Dark rearing from birth neither prevented nor delayed the upregulation. Rather unexpectedly, the expression of Kv3.1b protein and Kv3.2 mRNA and protein increased to higher levels from the third postnatal week onwards. Triple-labeling revealed that in dark-reared visual cortex Kv3.2 was upregulated in parvalbuminergic interneurons in supragranular layers which in normal animals rarely display Kv3.2 expression. Recovery from dark rearing normalized Kv3.2 expression. This showed that visual experience influences the Kv3 expression. The results suggest that an altered expression of Kv3 channels affects the functional properties of FS neurons, and may contribute to the deficits in inhibition observed in the sensory-deprived cortex.

  14. Effect of tyrphostin AG879 on Kv4.2 and Kv4.3 potassium channels

    PubMed Central

    Yu, Haibo; Zou, Beiyan; Wang, Xiaoliang; Li, Min

    2015-01-01

    Background and Purpose A-type potassium channels (IA) are important proteins for modulating neuronal membrane excitability. The expression and activity of Kv4.2 channels are critical for neurological functions and pharmacological inhibitors of Kv4.2 channels may have therapeutic potential for Fragile X syndrome. While screening various compounds, we identified tyrphostin AG879, a tyrosine kinase inhibitor, as a Kv4.2 inhibitor from. In the present study we characterized the effect of AG879 on cloned Kv4.2/Kv channel-interacting protein 2 (KChIP2) channels. Experimental Approach To screen the library of pharmacologically active compounds, the thallium flux assay was performed on HEK-293 cells transiently-transfected with Kv4.2 cDNA using the Maxcyte transfection system. The effects of AG879 were further examined on CHO-K1 cells expressing Kv4.2/KChIP2 channels using a whole-cell patch-clamp technique. Key Results Tyrphostin AG879 selectively and dose-dependently inhibited Kv4.2 and Kv4.3 channels. In Kv4.2/KChIP2 channels, AG879 induced prominent acceleration of the inactivation rate, use-dependent block and slowed the recovery from inactivation. AG879 induced a hyperpolarizing shift in the voltage-dependence of the steady-state inactivation of Kv4.2 channels without apparent effect on the V1/2 of the voltage-dependent activation. The blocking effect of AG879 was enhanced as channel inactivation increased. Furthermore, AG879 significantly inhibited the A-type potassium currents in the cultured hippocampus neurons. Conclusion and Implications AG879 was identified as a selective and potent inhibitor the Kv4.2 channel. AG879 inhibited Kv4.2 channels by preferentially interacting with the open state and further accelerating their inactivation. PMID:25752739

  15. Quantitative analysis of neurons with Kv3 potassium channel subunits, Kv3.1b and Kv3.2, in macaque primary visual cortex.

    PubMed

    Constantinople, Christine M; Disney, Anita A; Maffie, Jonathan; Rudy, Bernardo; Hawken, Michael J

    2009-10-01

    Voltage-gated potassium channels that are composed of Kv3 subunits exhibit distinct electrophysiological properties: activation at more depolarized potentials than other voltage-gated K+ channels and fast kinetics. These channels have been shown to contribute to the high-frequency firing of fast-spiking (FS) GABAergic interneurons in the rat and mouse brain. In the rodent neocortex there are distinct patterns of expression for the Kv3.1b and Kv3.2 channel subunits and of coexpression of these subunits with neurochemical markers, such as the calcium-binding proteins parvalbumin (PV) and calbindin D-28K (CB). The distribution of Kv3 channels and interrelationship with calcium-binding protein expression has not been investigated in primate cortex. We used immunoperoxidase and immunofluorescent labeling and stereological counting techniques to characterize the laminar and cell-type distributions of Kv3-immunoreactive (ir) neurons in macaque V1. We found that across the cortical layers approximately 25% of both Kv3.1b- and Kv3.2-ir neurons are non-GABAergic. In contrast, all Kv3-ir neurons in rodent cortex are GABAergic (Chow et al. [1999] J Neurosci. 19:9332-9345). The putatively excitatory Kv3-ir neurons were mostly located in layers 2, 3, and 4b. Further, the proportion of Kv3-ir neurons that express PV or CB also differs between macaque V1 and rodent cortex. These data indicate that, within the population of cortical neurons, a broader population of neurons, encompassing cells of a wider range of morphological classes may be capable of sustaining high-frequency firing in macaque V1.

  16. Development of extruded dielectric underground transmission cables rated 138 kV, 230 kV, and 345 kV. Final report

    SciTech Connect

    Bahder, G.; Bopp, L.A.; Eager, G.S.; Katz, C.; Knott, A.; Schmidt, G.A.

    1982-02-01

    This report covers the continuation of the work to develop technology to manufacture chemically crosslinked polyethylene insulated power cables in the ac voltage range of 138 kV to 345 kV having insulation thicknesses approximately equal to that of oil impregnated paper insulated cables. It also incorporates the development of field molded splices and terminations for new high voltage stress 138 kV cables. After reviewing the main equipment elements, incorporated in the pilot extrusion line, the special features of this system are noted and a step-by-step description of the cable extrusion process is given. Optimization of the process and introduction of modifications in the equipment culminated with the production of 138 kV cables. Results of laboratory tests to demonstrate the high quality of the cables are given. The development of molded splices and molded stress control cones was initiated with the work on model cables and followed by the making of splices and terminations on 138 kV cables. The molded components are made with the same purified insulating compound as used in the manufacture of the cables. Both the molded splices and the molded stress control cones have been fully tested in the laboratory. Following the completion of the development of the 138 kV cable a high stress 230 kV crosslinked polyethylene cable was developed and optimized. A full evaluation program similar to the one utilized on the 138 kV cable was carried out. Subsequently, work to develop a 345 kV high voltage stress cable, having insulation thickness of 1.02'' was undertaken. 345 kV cables were successfully manufactured and tested. However, additional work is required to further optimize the quality of this cable.

  17. Adult cancers near high-voltage overhead power lines.

    PubMed

    Elliott, Paul; Shaddick, Gavin; Douglass, Margaret; de Hoogh, Kees; Briggs, David J; Toledano, Mireille B

    2013-03-01

    Extremely low-frequency magnetic fields are designated as possibly carcinogenic in humans, based on an epidemiologic association with childhood leukemia. Evidence for associations with adult cancers is weaker and inconsistent. We conducted a case-control study to investigate risks of adult cancers in relation to distance and extremely low-frequency magnetic fields from high-voltage overhead power lines using National Cancer Registry Data in England and Wales, 1974-2008. The study included 7823 leukemia, 6781 brain/central nervous system cancers, 9153 malignant melanoma, 29,202 female breast cancer cases, and 79,507 controls frequency-matched on year and region (three controls per case except for female breast cancer, one control per case) 15-74 years of age living within 1000 m of a high-voltage overhead power line. There were no clear patterns of excess risk with distance from power lines. After adjustment for confounders (age, sex [except breast cancer], deprivation, rurality), for distances closest to the power lines (0-49 m) compared with distances 600-1000 m, odds ratios (ORs) ranged from 0.82 (95% confidence interval = 0.61-1.11; 66 cases) for malignant melanoma to 1.22 (0.88-1.69) for brain/central nervous system cancer. We observed no meaningful excess risks and no trends of risk with magnetic field strength for the four cancers examined. In adjusted analyses at the highest estimated field strength, ≥1000 nanotesla (nT), compared with <100 nT, ORs ranged from 0.68 (0.39-1.17) for malignant melanoma to 1.08 (0.77-1.51) for female breast cancer. Our results do not support an epidemiologic association of adult cancers with residential magnetic fields in proximity to high-voltage overhead power lines.

  18. Contributions of Kv3 channels to neuronal excitability.

    PubMed

    Rudy, B; Chow, A; Lau, D; Amarillo, Y; Ozaita, A; Saganich, M; Moreno, H; Nadal, M S; Hernandez-Pineda, R; Hernandez-Cruz, A; Erisir, A; Leonard, C; Vega-Saenz de Miera, E

    1999-04-30

    Four mammalian Kv3 genes have been identified, each of which generates, by alternative splicing, multiple protein products differing in their C-terminal sequence. Products of the Kv3.1 and Kv3.2 genes express similar delayed-rectifier type currents in heterologous expression systems, while Kv3.3 and Kv3.4 proteins express A-type currents. All Kv3 currents activate relatively fast at voltages more positive than -10 mV, and deactivate very fast. The distribution of Kv3 mRNAs in the rodent CNS was studied by in situ hybridization, and the localization of Kv3.1 and Kv3.2 proteins has been studied by immunohistochemistry. Most Kv3.2 mRNAs (approximately 90%) are present in thalamic-relay neurons throughout the dorsal thalamus. The protein is expressed mainly in the axons and terminals of these neurons. Kv3.2 channels are thought to be important for thalamocortical signal transmission. Kv3.1 and Kv3.2 proteins are coexpressed in some neuronal populations such as in fast-spiking interneurons of the cortex and hippocampus, and neurons in the globus pallidus. Coprecipitation studies suggest that in these cells the two types of protein form heteromeric channels. Kv3 proteins appear to mediate, in native neurons, similar currents to those seen in heterologous expression systems. The activation voltage and fast deactivation rates are believed to allow these channels to help repolarize action potentials fast without affecting the threshold for action potential generation. The fast deactivating current generates a quickly recovering after hyperpolarization, thus maximizing the rate of recovery of Na+ channel inactivation without contributing to an increase in the duration of the refractory period. These properties are believed to contribute to the ability of neurons to fire at high frequencies and to help regulate the fidelity of synaptic transmission. Experimental evidence has now become available showing that Kv3.1-Kv3.2 channels play critical roles in the generation of fast

  19. The anticonvulsant retigabine suppresses neuronal KV2-mediated currents

    PubMed Central

    Stas, Jeroen I.; Bocksteins, Elke; Jensen, Camilla S.; Schmitt, Nicole; Snyders, Dirk J.

    2016-01-01

    Enhancement of neuronal M-currents, generated through KV7.2-KV7.5 channels, has gained much interest for its potential in developing treatments for hyperexcitability-related disorders such as epilepsy. Retigabine, a KV7 channel opener, has proven to be an effective anticonvulsant and has recently also gained attention due to its neuroprotective properties. In the present study, we found that the auxiliary KCNE2 subunit reduced the KV7.2-KV7.3 retigabine sensitivity approximately 5-fold. In addition, using both mammalian expression systems and cultured hippocampal neurons we determined that low μM retigabine concentrations had ‘off-target’ effects on KV2.1 channels which have recently been implicated in apoptosis. Clinical retigabine concentrations (0.3–3 μM) inhibited KV2.1 channel function upon prolonged exposure. The suppression of the KV2.1 conductance was only partially reversible. Our results identified KV2.1 as a new molecular target for retigabine, thus giving a potential explanation for retigabine’s neuroprotective properties. PMID:27734968

  20. Improved Overhead Accounting in the NLC Main Linac

    SciTech Connect

    Tenenbaum, P.

    2004-06-10

    The NLC main linac contains 1,116 RF power units, of which 5% are considered ''spares'' for replacement of failed power units, make-up of the energy gain during an RF breakdown, and energy feedback. A more careful accounting for the effects of beam loading indicates that the NLC can operate with less BNS overhead and a smaller mean phase offset than was originally specified, and that as a consequence the total number of spares is actually about 7.9% of the total.

  1. Path-sensitive analysis for reducing rollback overheads

    DOEpatents

    O'Brien, John K.P.; Wang, Kai-Ting Amy; Yamashita, Mark; Zhuang, Xiaotong

    2014-07-22

    A mechanism is provided for path-sensitive analysis for reducing rollback overheads. The mechanism receives, in a compiler, program code to be compiled to form compiled code. The mechanism divides the code into basic blocks. The mechanism then determines a restore register set for each of the one or more basic blocks to form one or more restore register sets. The mechanism then stores the one or more register sets such that responsive to a rollback during execution of the compiled code. A rollback routine identifies a restore register set from the one or more restore register sets and restores registers identified in the identified restore register set.

  2. SHOULDER MUSCLE IMBALANCE AND SUBACROMIAL IMPINGEMENT SYNDROME IN OVERHEAD ATHLETES

    PubMed Central

    2011-01-01

    Subacromial impingement is a frequent and painful condition among athletes, particularly those involved in overhead sports such as baseball and swimming. There are generally two types of subacromial impingement: structural and functional. While structural impingement is caused by a physical loss of area in the subacromial space due to bony growth or inflammation, functional impingement is a relative loss of subacromial space secondary to altered scapulohumeral mechanics resulting from glenohumeral instability and muscle imbalance. The purpose of this review is to describe the role of muscle imbalance in subacromial impingement in order to guide sports physical therapy evaluation and interventions. PMID:21655457

  3. 88. Overhead view of clear air station site at early ...

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

    88. Overhead view of clear air station site at early stage of construction. View is from south 30 degrees west showing DR 3 in foreground with DR 2 in middle and DR 1 out of view. Official photograph BMEWS Project by unknown photographer, 5 October, 1959, Photographic Services, Riverton, NJ, BMEWS, clear as negative no. A-27. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

  4. Field evaluation of a modified intervention for overhead drilling.

    PubMed

    Rempel, David; Star, Demetra; Barr, Alan; Blanco, Marco Mendoza; Janowitz, Ira

    2010-04-01

    Drilling holes into concrete or metal ceilings is one of the most physically demanding tasks performed in construction. The work is done overhead with rotary impact hammer drills that weigh up to 40 N. The task is associated with pain and musculoskeletal disorders at the wrist, forearm, shoulder, and back. The mechanism of injury is thought to be the high forces and non-neutral shoulder and wrist postures applied during drilling. Previously, we described a field study of a foot lever and inverted drill press intervention devices that received poor usability ratings compared with the usual method for overhead drilling based on problems with mobility and productivity. Using a participatory intervention model, feedback from construction workers (N = 13) was used to develop a new intervention design that incorporated a wheeled tripod base and a unique method of aligning the drilling column to vertical. A different group of construction workers (N = 23) evaluated usability and fatigue of the new device during their regular overhead drilling in comparison with the usual method. Four of 12 usability ratings were significantly better with the intervention device compared with the usual method. Subjective shoulder fatigue was less with the new intervention (1.1 vs. 3.3; scale 0 to 5; p < 0.001). This difference was supported by objective outcome measures; the mean hand forces during drilling were 26 N with the intervention compared with 245 N with the usual method. The percentage of time with the shoulder flexed or abducted to more than 60 degrees was less with the intervention compared with the usual method (21 vs. 40%; p = 0.007). There was significantly less head extension with the intervention compared with the usual method. There were no significant differences in overall productivity between the two methods. This study demonstrates that a new intervention device for overhead drilling has improved usability and subjective fatigue ratings compared with the usual method

  5. The impact of overhead lines for employees with stents

    NASA Astrophysics Data System (ADS)

    Syrek, P.; Skowron, M.

    2017-05-01

    The aim of article is to discuss interaction between stents implanted in the body of worker and harmonic magnetic field in the vicinity of electric wires. In last decades, a growing proportion of people has any devices implanted, to list: cardiac pacemakers, cardioverter - defibrillators. Recommendations of International Commision on Non-ionizing Radiation Protection (ICNIRP), and resctrictions imposed in different states, may exlude specific individuals from their duties. The autors focused on the situation, when the employee with stent, works in the immediate vicinity of overhead electric wires, cleaning with dry ice the electric insulators.

  6. Evaluation of Impingement Syndromes in the Overhead-Throwing Athlete

    PubMed Central

    Jobe, Christopher M.; Coen, Michael J.; Screnar, Pat

    2000-01-01

    Objective: We outline impingement entities, describe the history and physical examination, and provide an overview of treatment beyond that routinely used in glenohumeral and scapulothoracic dysfunction. Background: In the athlete, pain and dysfunction due to excessive overhead use or abnormal positioning of the shoulder is common and can result from multiple etiologies, including impingement syndromes. Primary, secondary, internal, and coracoid impingement have all been described. Description: These entities will be discussed, including pathology, evaluation, and treatment. Clinical Advantages: Incorporating a systematic evaluation and treatment of impingement syndromes optimizes care for the patient with shoulder pain. PMID:16558643

  7. Combined MV + kV inverse treatment planning for optimal kV dose incorporation in IGRT

    NASA Astrophysics Data System (ADS)

    Grelewicz, Zachary; Wiersma, Rodney D.

    2014-04-01

    Despite the existence of real-time kV intra-fractional tumor tracking strategies for many years, clinical adoption has been held back by concern over the excess kV imaging dose cost to the patient when imaging in continuous fluoroscopic mode. This work aims to solve this problem by investigating, for the first time, the use of convex optimization tools to optimally integrate this excess kV imaging dose into the MV therapeutic dose in order to make real-time kV tracking clinically feasible. Phase space files modeling both a 6 MV treatment beam and a kV on-board-imaging beam of a commercial LINAC were generated with BEAMnrc, and used to generate dose influence matrices in DOSXYZnrc for ten previously treated lung cancer patients. The dose optimization problem for IMRT, formulated as a quadratic problem, was modified to include additional constraints as required for real-time kV intra-fractional tracking. An interior point optimizer was used to solve the modified optimization problem. It was found that when using large kV imaging apertures during fluoroscopic tracking, combined MV + kV optimization lead to a 0.5%-5.17% reduction in the total number of monitor units assigned to the MV beam due to inclusion of the kV dose over the ten patients. This was accompanied by a reduction of up to 42% of the excess kV dose compared to standard MV IMRT with kV tracking. For all kV field sizes considered, combined MV + kV optimization provided prescription dose to the treatment volume coverage equal to the no-imaging case, yet superior to standard MV IMRT with non-optimized kV fluoroscopic tracking. With combined MV + kV optimization, it is possible to quantify in a patient specific way the dosimetric effect of real-time imaging on the patient. Such information is necessary when substantial kV imaging is performed.

  8. 220-kV combined optical transformer

    NASA Astrophysics Data System (ADS)

    Cui, Ying; Ye, Miaoyuan; Zhu, Yong; Xu, Yan; Luo, Sunan

    2000-10-01

    The magneto-optic current and electro-optic voltage sensing technologies were combined into a single phase unit which provides a new solution for combined current and voltage sensing and relaying applications. It senses voltage and current by making utilities of Pockels electro-optic effect of a BGO(Bi4Ge3O12) crystal and Faraday magneto-optic effect of a close-loop flint. The 220 kV high voltage is directly applied on the BGO crystal without capacitive dividers. This design permits true optical voltage measurement to be performed for the highest possible accuracy and stability. In the current sensor, a light beam circles around the current carrying conductor. The effect of the location movement of the conductor and external magnetic field are reduced. It has superior advantages of compact size, light- weight and better performance compared with conventional current and voltage transformers. Composite bushing consisting of a fiberglass tube support and silicone rubber that is filled with SF6 gas is employed for HV insulation. Connections between the Combined Optical Transformers in the substation and the metering and protecting unit in the control house are via optical fiber cable. The fundamental principal, system design and test result of this new 220 kV Combined Optical Transformer will be introduced in this paper.

  9. Constitutive Activation of the Shaker Kv Channel

    PubMed Central

    Sukhareva, Manana; Hackos, David H.; Swartz, Kenton J.

    2003-01-01

    In different types of K+ channels the primary activation gate is thought to reside near the intracellular entrance to the ion conduction pore. In the Shaker Kv channel the gate is closed at negative membrane voltages, but can be opened with membrane depolarization. In a previous study of the S6 activation gate in Shaker (Hackos, D.H., T.H. Chang, and K.J. Swartz. 2002. J. Gen. Physiol. 119:521–532.), we found that mutation of Pro 475 to Asp results in a channel that displays a large macroscopic conductance at negative membrane voltages, with only small increases in conductance with membrane depolarization. In the present study we explore the mechanism underlying this constitutively conducting phenotype using both macroscopic and single-channel recordings, and probes that interact with the voltage sensors or the intracellular entrance to the ion conduction pore. Our results suggest that constitutive conduction results from a dramatic perturbation of the closed-open equilibrium, enabling opening of the activation gate without voltage-sensor activation. This mechanism is discussed in the context of allosteric models for activation of Kv channels and what is known about the structure of this critical region in K+ channels. PMID:14557403

  10. Steal Tree: Low-Overhead Tracing of Work Stealing Schedulers

    SciTech Connect

    Lifflander, Jonathan; Krishnamoorthy, Sriram; Kale, Laxmikant

    2013-06-16

    Work stealing is a popular approach to scheduling task-parallel programs. The flexibility inherent in work stealing when dealing with load imbalance results in seemingly irregular computation structures, complicating the study of its runtime behavior. In this paper, we present an approach to efficiently trace async-finish parallel programs scheduled using work stealing. We identify key properties that allow us to trace the execution of tasks with low time and space overheads. We also study the usefulness of the proposed schemes in supporting algorithms for data-race detection and retentive steal- ing presented in the literature. We demonstrate that the perturbation due to tracing is within the variation in the execution time with 99% confidence and the traces are concise, amounting to a few tens of kilobytes per thread in most cases. We also demonstrate that the traces enable significant reductions in the cost of detecting data races and result in low, stable space overheads in supporting retentive stealing for async-finish programs.

  11. Overhead cam shaft type V-engine cylinder block

    SciTech Connect

    Tominaga, N.; Kurai, N.; Ueno, H.; Suzuki, S.

    1987-01-06

    This patent describes an overhead camshaft type V-engine having V-shaped cylinders equipped with and overhead camshaft drive by a timing chain disposed and arranged on either side of the cylinders at a right angle to a crankshaft. The improvement comprises: a cylinder block; a timing chain passage in the cylinder block, the passage housing the timing chain movement in a plane of the chain. The passage includes a spacing on each side of a pair of runs of the chain, and in the plane, the spacing on each side of a pair of runs of the chain being substantially the same; the block further including a wall at least partially bounding the spacings and intersecting the plane. The wall has symmetrical wall openings therethrough symmetrically disposed on opposite sides of the chain and its plane, and opening into a respective substantially same spacing; a plurality of chain guide means, each mounted in a respective substantially same spacing; and tensioning means resiliently biasing one of the chain guide means toward and against a run of the chain to place the chain in tension, at least a portion of the tensioning means being mounted in one of the symmetrical wall openings adjacent to the respective run. The symmetry of the symmetrical wall openings enable the tensioning means to be positioned adjacent to either run, whereby the cylinder block may be used for diametrically opposite cylinders.

  12. Gamma-ray dose from an overhead plume

    DOE PAGES

    McNaughton, Michael W.; Gillis, Jessica McDonnel; Ruedig, Elizabeth; ...

    2017-05-01

    Standard plume models can underestimate the gamma-ray dose when most of the radioactive material is above the heads of the receptors. Typically, a model is used to calculate the air concentration at the height of the receptor, and the dose is calculated by multiplying the air concentration by a concentration-to-dose conversion factor. Models indicate that if the plume is emitted from a stack during stable atmospheric conditions, the lower edges of the plume may not reach the ground, in which case both the ground-level concentration and the dose are usually reported as zero. However, in such cases, the dose frommore » overhead gamma-emitting radionuclides may be substantial. Such underestimates could impact decision making in emergency situations. The Monte Carlo N-Particle code, MCNP, was used to calculate the overhead shine dose and to compare with standard plume models. At long distances and during unstable atmospheric conditions, the MCNP results agree with the standard models. As a result, at short distances, where many models calculate zero, the true dose (as modeled by MCNP) can be estimated with simple equations.« less

  13. Vertical Jump Biomechanics Altered With Virtual Overhead Goal.

    PubMed

    Ford, Kevin R; Nguyen, Anh-Dung; Hegedus, Eric J; Taylor, Jeffrey B

    2017-04-01

    Virtual environments with real-time feedback can simulate extrinsic goals that mimic real life conditions. The purpose was to compare jump performance and biomechanics with a physical overhead goal (POG) and with a virtual overhead goal (VOG). Fourteen female subjects participated (age: 18.8 ± 1.1 years, height: 163.2 ± 8.1 cm, weight 63.0 ± 7.9 kg). Sagittal plane trunk, hip, and knee biomechanics were calculated during the landing and take-off phases of drop vertical jump with different goal conditions. Repeated-measures ANOVAs determined differences between goal conditions. Vertical jump height displacement was not different during VOG compared with POG. Greater hip extensor moment (P < .001*) and hip angular impulse (P < .004*) were found during VOG compared with POG. Subjects landed more erect with less magnitude of trunk flexion (P = .002*) during POG compared with VOG. A virtual target can optimize jump height and promote increased hip moments and trunk flexion. This may be a useful alternative to physical targets to improve performance during certain biomechanical testing, screening, and training conditions.

  14. Rehabilitation of the Overhead Athlete’s Elbow

    PubMed Central

    Wilk, Kevin E.; Macrina, Leonard C.; Cain, E. Lyle; Dugas, Jeffrey R.; Andrews, James R.

    2012-01-01

    The activities required during overhead sports, particularly during baseball pitching, produce large forces at the elbow joint. Injuries to the elbow joint frequently occur in the overhead athlete because of the large amount of forces observed during the act of throwing, playing tennis, or playing golf. Injuries may result because of repetitive overuse, leading to tissue failure. Rehabilitation following injury or surgery to the throwing elbow is vital to fully restore normal function and return the athlete to competition as quickly and safely as possible. Rehabilitation of the elbow, whether following injury or postsurgical, must follow a progressive and sequential order, building on the previous phase, to ensure that healing tissues are not compromised. Emphasis is placed on restoring full motion, muscular strength, and neuromuscular control while gradually applying loads to healing tissue. In addition, when one is creating a rehabilitation plan for athletes, it is imperative to treat the entire upper extremity, core, and legs to create and dissipate the forces generated at each joint. PMID:23016113

  15. TAUOVERSUPERMON: LOW-OVERHEAD ONLINE PARALLEL PERFORMANCE MONITORING

    SciTech Connect

    SOTTILE, MATTHEW JOSEPH; NATARAJ, AROON; MALONY, ALLEN; MORRIS, ALAN; SHENDE, SAMEER

    2007-01-30

    Online or Real-time application performance monitoring allows tracking performance characteristics during execution as opposed to doing so post-mortem. This opens up several possibilities otherwise unavailable such as real-time visualization and application performance steering that can be useful in the context of long-running applications. Two fundamental components that constitute such a performance monitor are the measurement and transport systems. The former captures performance metrics of individual contexts (processes, threads). The latter enables querying the parallel/distributed state from the different contexts and also allows measurement control. As HPC systems grow in size and complexity, the key challenge is to keep the online performance monitor scalable and low overhead while still providing a useful performance reporting capability. We adapt and combine two existing, mature systems - Tuning and Analysis Utility (TAU) and Supermon - to address this problem. Tau performs the measurement while Supermon is used to collect the distributed measurement state. Our experiments show that this novel approach of using a cluster-monitor, Supermon, as the transport for online performance data from Tau leads to very low-overhead application monitoring as well as other beneits unavailable from using a traditional transport such as NFS.

  16. Output gating performance overhead elimination for scan test

    NASA Astrophysics Data System (ADS)

    Suhag, Ashok Kumar; Ahlawat, Satdev; Shrivastava, Vivek; Choudhary, Rahul Raj

    2015-07-01

    Switching activity is much higher in test mode as compared to normal mode of operation which causes higher power dissipation, and this leads to several reliability issues. Output gating is proposed as a very effective low-power test technique, which is used to eliminate redundant switching activity in the combinational logic of circuit under test (CUT) during the shifting of test vectors in a scan chain. This method reduces the average power significantly, but it introduces performance overhead in normal mode of operation. In this work, a new output gating technique is proposed which eliminates redundant switching activity in combinational logic of CUT during shifting of test vectors without any negative impact on performance as compared to earlier proposed output gating techniques. The proposed design also improves the performance of the scan flop in functional mode with negligible area overhead incurred due to extra transistors. Experimental results show that our design has a more robust performance over wide range of capacitive load as compared to earlier designs.

  17. Effect of NIP-142 on potassium channel alpha-subunits Kv1.5, Kv4.2 and Kv4.3, and mouse atrial repolarization.

    PubMed

    Tanaka, Hikaru; Namekata, Iyuki; Hamaguchi, Shogo; Kawamura, Taro; Masuda, Hiroyuki; Tanaka, Yoshio; Iida-Tanaka, Naoko; Takahara, Akira

    2010-01-01

    Effects of NIP-142, a benzopyran compound which terminates experimental atrial arrhythmia, on potassium channel alpha-subunits and mouse atrial repolarization were examined. NIP-142 concentration-dependently blocked the outward current through potassium channel alpha subunits Kv1.5, Kv4.2 and Kv4.3 expressed in Xenopus oocytes. In isolated mouse atrial myocardia, NIP-142 prolonged the action potential duration and effective refractory period, and increased the contractile force. These results suggest that NIP-142 blocks the potassium channels underlying the transient and sustained outward currents, which may contribute to its antiarrhythmic activity.

  18. Evaluation of Instrumentation and Dynamic Thermal Ratings for Overhead Lines

    SciTech Connect

    Phillips, A.

    2013-01-31

    In 2010, a project was initiated through a partnership between the Department of Energy (DOE) and the New York Power Authority (NYPA) to evaluate EPRI's rating technology and instrumentation that can be used to monitor the thermal states of transmission lines and provide the required real-time data for real-time rating calculations. The project included the installation and maintenance of various instruments at three 230 kV line sites in northern New York. The instruments were monitored, and data collection and rating calculations were performed for about a three year period.

  19. Development of sensorless easy-to-use overhead crane system via simulation based control

    NASA Astrophysics Data System (ADS)

    Tagawa, Yasutaka; Mori, Yoshihito; Wada, Masaomi; Kawajiri, Eisaku; Nouzuka, Kazuma

    2016-09-01

    This paper describes the newly developed overhead crane which has a sensorless vibration control system. Generally, loads which are carried by the overhead cranes are easy to vibrate and only skilled people can operate the cranes. Therefore, a lot of studies have been done to solve this problem by using feedback control with vibration sensors. However vibration sensors often break down in severe industrial environment and more reliable control systems are required. For this reason, we have been developing sensorless control system for overhead cranes. In this paper, we firstly introduce basic idea of simulation based control which is called IDCS, then overview and modeling of the overhead crane is presented. Next, the control system design of the overhead crane is discussed, and experimental results are shown for real overhead crane with 2 axes.

  20. Kv1.1 and Kv1.3 channels contribute to the degeneration of retinal ganglion cells after optic nerve transection in vivo.

    PubMed

    Koeberle, P D; Wang, Y; Schlichter, L C

    2010-01-01

    Degeneration of retinal ganglion cells (RGCs) - an important cause of visual impairment - is often modeled by optic nerve transection, which leads to apoptotic death of these central nervous system neurons. With this model, we show that specific voltage-gated K(+) channels (Kv1 family) contribute to the degeneration of rat RGCs and expression of apoptosis-related molecules in vivo. Retinal expression of Kv1.1, Kv1.2, Kv1.3 and Kv1.5 was examined by quantitative real-time reverse transcriptase-PCR and immunohistochemistry. Kv channel blockers and channel-specific short-interfering RNAs (siRNAs) were used to assess their roles in RGC degeneration. We found that (i) rat RGCs express Kv1.1, Kv1.2 and Kv1.3 (but not Kv1.5); (ii) intraocular injection of agitoxin-2 or margatoxin, potent blockers of Kv1.1, Kv1.2 and Kv1.3 channels, dose-dependently reduced the RGC degeneration; (iii) siRNAs applied to the cut optic nerve were rapidly transported throughout RGCs only, in which they reduced the expression of the cognate channel only. Our results show differential roles of the channels; siRNAs directed against Kv1.1 or Kv1.3 channels greatly reduced RGC death, whereas Kv1.2-targeted siRNAs had only a small effect, and siRNAs against Kv1.5 were without effect. (iv) Kv1.1 and Kv1.3 channels apparently contribute to cell-autonomous death of RGCs through different components of the apoptotic machinery. Kv1.1 depletion increased the antiapoptotic gene, Bcl-X(L), whereas Kv1.3 depletion reduced the proapoptotic genes, caspase-3, caspase-9 and Bad.

  1. Implementation of a novel double-side technique for partial discharge detection and location in covered conductor overhead distribution networks

    NASA Astrophysics Data System (ADS)

    He, Weisheng; Li, Hongjie; Liang, Deliang; Sun, Haojie; Yang, Chenbo; Wei, Jinqu; Yuan, Zhijian

    2015-12-01

    Partial discharge (PD) detection has proven to be one of the most acceptable techniques for on-line condition monitoring and predictive maintenance of power apparatus. A powerful tool for detecting PD in covered-conductor (CC) lines is urgently needed to improve the asset management of CC overhead distribution lines. In this paper, an appropriate, portable and simple system designed to detect PD activity in CC lines and ultimately pinpoint the PD source is developed and tested. The system is based on a novel double-side synchronised PD measurement technique driven by pulse injection. Emphasis is placed on the proposed PD-location mechanism and hardware structure, with descriptions of the pulse-injection process, detection device, synchronisation principle and PD-location algorithm. The system is simulated using ATP-EMTP, and the simulated results are found to be consistent with the actual simulation layout. For further validation, the capability of the system is tested in a high-voltage laboratory experiment using a 10-kV CC line with cross-linked polyethylene insulation.

  2. Software in the DOE: The Hidden Overhead of''The Build''

    SciTech Connect

    Kumfert, G; Epperly, T

    2002-02-28

    ''The Build'' is the infrastructure needed to convert software from source code to usable form. It is intimately tied to the software it supports, knowing about every file and automating every transformation needed to produce a working program. Every developer knows that a project spends some labor overhead on ''the build.'' How big is this hidden overhead? According to 34 scientific software developers we surveyed at Lawrence Livermore National Labs, among colleagues at other DOE labs, and a handful of academics the ''perceived'' overhead averages around 12%. Individual cases of 20% to 30% were not uncommon. In one project claiming a 20% overhead, we found supporting evidence by combing through their CVS repository.

  3. Modulation of Kv7 channels and excitability in the brain.

    PubMed

    Greene, Derek L; Hoshi, Naoto

    2017-02-01

    Neuronal Kv7 channels underlie a voltage-gated non-inactivating potassium current known as the M-current. Due to its particular characteristics, Kv7 channels show pronounced control over the excitability of neurons. We will discuss various factors that have been shown to drastically alter the activity of this channel such as protein and phospholipid interactions, phosphorylation, calcium, and numerous neurotransmitters. Kv7 channels locate to key areas for the control of action potential initiation and propagation. Moreover, we will explore the dynamic surface expression of the channel modulated by neurotransmitters and neural activity. We will also focus on known principle functions of neural Kv7 channels: control of resting membrane potential and spiking threshold, setting the firing frequency, afterhyperpolarization after burst firing, theta resonance, and transient hyperexcitability from neurotransmitter-induced suppression of the M-current. Finally, we will discuss the contribution of altered Kv7 activity to pathologies such as epilepsy and cognitive deficits.

  4. Interactions between the C-terminus of Kv1.5 and Kvβ regulate pyridine nucleotide-dependent changes in channel gating

    PubMed Central

    Tipparaju, Srinivas M.; Li, Xiao-Ping; Kilfoil, Peter J.; Xue, Bin; Uversky, Vladimir N.; Bhatnagar, Aruni; Barski, Oleg A.

    2012-01-01

    Voltage-gated potassium (Kv) channels are tetrameric assemblies of transmembrane Kv proteins with cytosolic N- and C-termini. The N-terminal domain of Kv1 proteins binds to β-subunits, but the role of the C-terminus is less clear. Therefore, we studied the role of the C-terminus in regulating Kv1.5 channel and its interactions with Kvβ-subunits. When expressed in COS-7 cells, deletion of the C-terminal domain of Kv1.5 did not affect channel gating or kinetics. Co-expression of Kv1.5 with Kvβ3 increased current inactivation, whereas Kvβ2 caused a hyperpolarizing shift in the voltage-dependence of current activation. Inclusion of NADPH in the patch pipette solution accelerated the inactivation of Kv1.5-Kvβ3 currents. In contrast, NADP+ decreased the rate and the extent of Kvβ3-induced inactivation and reversed the hyperpolarizing shift in the voltage-dependence of activation induced by Kvβ2. Currents generated by Kv1.5ΔC+Kvβ3 or Kv1.5ΔC+Kvβ2 complexes did not respond to changes in intracellular pyridine nucleotide concentration, indicating that the C-terminus is required for pyridine nucleotide-dependent interactions between Kvβ and Kv1.5. A glutathione-S-transferase (GST) fusion protein containing the C-terminal peptide of Kv1.5 did not bind to apoKvβ2, but displayed higher affinity for Kvβ2:NADPH than Kvβ2:NADP+. The GST fusion protein also precipitated Kvβ proteins from mouse brain lysates. Pull-down experiments, structural analysis and electrophysiological data indicated that a specific region of the C-terminus (Arg543-Val583) is required for Kvβ binding. These results suggest that the C-terminal domain of Kv1.5 interacts with β-subunits and that this interaction is essential for the differential regulation of Kv currents by oxidized and reduced nucleotides. PMID:22426702

  5. Wearable IMU for Shoulder Injury Prevention in Overhead Sports

    PubMed Central

    Rawashdeh, Samir A.; Rafeldt, Derek A.; Uhl, Timothy L.

    2016-01-01

    Body-worn inertial sensors have enabled motion capture outside of the laboratory setting. In this work, an inertial measurement unit was attached to the upper arm to track and discriminate between shoulder motion gestures in order to help prevent shoulder over-use injuries in athletics through real-time preventative feedback. We present a detection and classification approach that can be used to count the number of times certain motion gestures occur. The application presented involves tracking baseball throws and volleyball serves, which are common overhead movements that can lead to shoulder and elbow overuse injuries. Eleven subjects are recruited to collect training, testing, and randomized validation data, which include throws, serves, and seven other exercises that serve as a large null class of similar movements, which is analogous to a realistic usage scenario and requires a robust estimator. PMID:27827880

  6. Hydro-mechanical overhead for internal combustion engine

    SciTech Connect

    Meistrick, Z.S.; Price, R.B.

    1987-05-12

    This patent describes a hydro-mechanical overhead for a multi-cylinder four-cycle internal combustion engine having a camshaft, intake valve pushtube means driven by the camshaft, exhaust valve pushtube means driven by the camshaft, at least one intake and exhaust valve for each cylinder of the multi-cylinder internal combustion engines and a piston for each cylinder of the engine. The process comprises an intake valve master piston means for each engine cylinder. Each intake valve master piston means is driven by one of the intake valve pushtube means. There is an exhaust valve master piston means for each engine cylinder, and each exhaust valve master piston means is driven by one of the exhaust valve pushtube means.

  7. Reducing the quantum-computing overhead with complex gate distillation

    NASA Astrophysics Data System (ADS)

    Duclos-Cianci, Guillaume; Poulin, David

    2015-04-01

    In leading fault-tolerant quantum-computing schemes, accurate transformations are obtained by a two-stage process. In a first stage, a discrete universal set of fault-tolerant operations is obtained by error-correcting noisy transformations and distilling resource states. In a second stage, arbitrary transformations are synthesized to desired accuracy by combining elements of this set into a circuit. Here we present a scheme that merges these two stages into a single one, directly distilling complex transformations. We find that our scheme can reduce the total overhead to realize certain gates by up to a few orders of magnitude. In contrast to other schemes, this efficient gate synthesis does not require computationally intensive compilation algorithms and a straightforward generalization of our scheme circumvents compilation and synthesis altogether.

  8. Wearable IMU for Shoulder Injury Prevention in Overhead Sports.

    PubMed

    Rawashdeh, Samir A; Rafeldt, Derek A; Uhl, Timothy L

    2016-11-03

    Body-worn inertial sensors have enabled motion capture outside of the laboratory setting. In this work, an inertial measurement unit was attached to the upper arm to track and discriminate between shoulder motion gestures in order to help prevent shoulder over-use injuries in athletics through real-time preventative feedback. We present a detection and classification approach that can be used to count the number of times certain motion gestures occur. The application presented involves tracking baseball throws and volleyball serves, which are common overhead movements that can lead to shoulder and elbow overuse injuries. Eleven subjects are recruited to collect training, testing, and randomized validation data, which include throws, serves, and seven other exercises that serve as a large null class of similar movements, which is analogous to a realistic usage scenario and requires a robust estimator.

  9. Phase Sensitive Cueing for 3D Objects in Overhead Images

    SciTech Connect

    Paglieroni, D W; Eppler, W G; Poland, D N

    2005-02-18

    A 3D solid model-aided object cueing method that matches phase angles of directional derivative vectors at image pixels to phase angles of vectors normal to projected model edges is described. It is intended for finding specific types of objects at arbitrary position and orientation in overhead images, independent of spatial resolution, obliqueness, acquisition conditions, and type of imaging sensor. It is shown that the phase similarity measure can be efficiently evaluated over all combinations of model position and orientation using the FFT. The highest degree of similarity over all model orientations is captured in a match surface of similarity values vs. model position. Unambiguous peaks in this surface are sorted in descending order of similarity value, and the small image thumbnails that contain them are presented to human analysts for inspection in sorted order.

  10. 138 kV 12-phase as an alternative to 345 kV 3-phase

    SciTech Connect

    Stewart, J.R.; Hudson, T.L.

    1988-04-01

    Recent high phase order reserch has resulted in a 138 kV (phase-to-ground) 12-phase line design which is a realistic alternatice to 345 kV 3-phase transmission. This paper presnts the results of an experimental and analytical program which included construction of a 12-phase steel lattice portal tower special insulators, consttruction of a 12-phase substation, and subsequent energization of the world's first 12-phase power transmission line. Impedences, electrical environmental effects (radio noise, audible noise, and electric fields) are among the parameters measured and evaluated. This 12-phase design is compared with sevral existing 345 kV 3-phase lines for thermal and surge impedance loading, electrical environmental effects and physical size requirements. The 12-phase design offers comparable loading in less space with reduced electrical environmental impact. This is illustrative of the possibilities of high phase order as a replacement for 3-phase at other voltage levels. 9 refs., 13 figs., 2 tabs.

  11. COMPARISON OF SCAPULAR MUSCLE ACTIVATIONS DURING THREE OVERHEAD THROWING EXERCISES.

    PubMed

    Henning, Lisa; Plummer, Hillary; Oliver, Gretchen D

    2016-02-01

    With shoulder pain and injury on the rise in overhead athletes, clinicians are often examining preventative exercises to address functional abnormalities. Because shoulder impingement is prevalent in overhead athletes, much focus is on scapular stability and the function of the stabilizing force couple of the upper and lower trapezius and serratus anterior. The purpose of this study was to examine scapular muscle activation during a series of throws and holds (throwing without releasing) with two different ball weights (7oz and 12oz). It was hypothesized that the holds exercises would elicit greater activation of the scapular musculature than the throw, irrespective of ball weight. Case control laboratory study. Twenty-two NCAA Division I, right hand dominant, softball players (19.91 + 1.04 years; 169.24 + 7.36 cm; 72.09 + 10.61 kg) volunteered to participate. Surface EMG was utilized to measure muscle activity in the upper, middle and lower trapezius and serratus anterior muscles during three different throwing activities. MANOVA results revealed no significant differences in muscle activity between throwing conditions, F(16,82) = 1.02, p = 0.446, Wilks' Λ = 0.696, Cohen's d = 0.44 (7oz holds), 0.24 (12oz holds), power = 0.625. The results may provide some clinical insight in advocating the use of holds with different ball weights. The holds throw may be an effective step in shoulder strengthening that can more closely mimic the functional movement of throwing without the element of ball release. Level 3.

  12. Arrangement of Kv1 alpha subunits dictates sensitivity to tetraethylammonium.

    PubMed

    Al-Sabi, Ahmed; Shamotienko, Oleg; Dhochartaigh, Sorcha Ni; Muniyappa, Nagesh; Le Berre, Marie; Shaban, Hamdy; Wang, Jiafu; Sack, Jon T; Dolly, J Oliver

    2010-09-01

    Shaker-related Kv1 channels contain four channel-forming alpha subunits. Subfamily member Kv1.1 often occurs oligomerized with Kv1.2 alpha subunits in synaptic membranes, and so information was sought on the influence of their positions within tetramers on the channels' properties. Kv1.1 and 1.2 alpha genes were tandem linked in various arrangements, followed by expression as single-chain proteins in mammalian cells. As some concatenations reported previously seemed not to reliably position Kv1 subunits in their assemblies, the identity of expressed channels was methodically evaluated. Surface protein, isolated by biotinylation of intact transiently transfected HEK-293 cells, gave Kv1.1/1.2 reactivity on immunoblots with electrophoretic mobilities corresponding to full-length concatenated tetramers. There was no evidence of protein degradation, indicating that concatemers were delivered intact to the plasmalemma. Constructs with like genes adjacent (Kv1.1-1.1-1.2-1.2 or Kv1.2-1.2-1.1-1.1) yielded delayed-rectifying, voltage-dependent K(+) currents with activation parameters and inactivation kinetics slightly different from the diagonally positioned genes (Kv1.1-1.2-1.1-1.2 or 1.2-1.1-1.2-1.1). Pore-blocking petidergic toxins, alpha dendrotoxin, agitoxin-1, tityustoxin-Kalpha, and kaliotoxin, were unable to distinguish between the adjacent and diagonal concatamers. Unprecedentedly, external application of the pore-blocker tetraethylammonium (TEA) differentially inhibited the adjacent versus diagonal subunit arrangements, with diagonal constructs having enhanced susceptibility. Concatenation did not directly alter the sensitivities of homomeric Kv1.1 or 1.2 channels to TEA or the toxins. TEA inhibition of currents generated by channels made up from dimers (Kv1.1-1.2 and/or Kv1.2-1.1) was similar to the adjacently arranged constructs. These collective findings indicate that assembly of alpha subunits can be directed by this optimized concatenation, and that subunit

  13. Structural Insight into KCNQ (Kv7) Channel Assembly and Channelopathy

    PubMed Central

    Howard, Rebecca J.; Clark, Kimberly A.; Holton, James M.; Minor, Daniel L.

    2010-01-01

    Summary Kv7.x (KCNQ) voltage-gated potassium channels form the cardiac and auditory IKs current and the neuronal M-current. The five Kv7 subtypes have distinct assembly preferences encoded by a C-terminal cytoplasmic assembly domain, the A-domain Tail. Here, we present the high-resolution structure of the Kv7.4 A-domain Tail together with biochemical experiments that show that the domain is a self-assembling, parallel, four-stranded coiled coil. Structural analysis and biochemical studies indicate conservation of the coiled coil in all Kv7 subtypes and that a limited set of interactions encode assembly specificity determinants. Kv7 mutations have prominent roles in arrhythmias, deafness, and epilepsy. The structure together with biochemical data indicate that A-domain Tail arrhythmia mutations cluster on the solvent-accessible surface of the subunit interface at a likely site of action for modulatory proteins. Together, the data provide a framework for understanding Kv7 assembly specificity and the molecular basis of a distinct set of Kv7 channelopathies. PMID:17329207

  14. Assessment of 69 kV Underground Cable Thermal Ratings using Distributed Temperature Sensing

    NASA Astrophysics Data System (ADS)

    Stowers, Travis

    Underground transmission cables in power systems are less likely to experience electrical faults, however, resulting outage times are much greater in the event that a failure does occur. Unlike overhead lines, underground cables are not self-healing from flashover events. The faulted section must be located and repaired before the line can be put back into service. Since this will often require excavation of the underground duct bank, the procedure to repair the faulted section is both costly and time consuming. These added complications are the prime motivators for developing accurate and reliable ratings for underground cable circuits. This work will review the methods by which power ratings, or ampacity, for underground cables are determined and then evaluate those ratings by making comparison with measured data taken from an underground 69 kV cable, which is part of the Salt River Project (SRP) power subtransmission system. The process of acquiring, installing, and commissioning the temperature monitoring system is covered in detail as well. The collected data are also used to evaluate typical assumptions made when determining underground cable ratings such as cable hot-spot location and ambient temperatures. Analysis results show that the commonly made assumption that the deepest portion of an underground power cable installation will be the hot-spot location does not always hold true. It is shown that distributed cable temperature measurements can be used to locate the proper line segment to be used for cable ampacity calculations.

  15. 31 CFR Appendix I(f) to Part 13 - Estimated Overhead and Administrative Costs

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance: Treasury 1 2012-07-01 2012-07-01 false Estimated Overhead and Administrative Costs I(F) Appendix I(F) to Part 13 Money and Finance: Treasury Office of the Secretary of the Treasury... Pt. 13, App. I(F) Appendix I(F) to Part 13—Estimated Overhead and Administrative Costs Date:...

  16. 31 CFR Appendix I(f) to Part 13 - Estimated Overhead and Administrative Costs

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance: Treasury 1 2013-07-01 2013-07-01 false Estimated Overhead and Administrative Costs I(F) Appendix I(F) to Part 13 Money and Finance: Treasury Office of the Secretary of the Treasury... Pt. 13, App. I(F) Appendix I(F) to Part 13—Estimated Overhead and Administrative Costs Date:...

  17. 31 CFR Appendix II(f) to Part 13 - Overhead and Administrative Costs

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Overhead and Administrative Costs II(F) Appendix II(F) to Part 13 Money and Finance: Treasury Office of the Secretary of the Treasury... Pt. 13, App. II(F) Appendix II(F) to Part 13—Overhead and Administrative Costs Date: Select Only...

  18. 31 CFR Appendix II(f) to Part 13 - Overhead and Administrative Costs

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance: Treasury 1 2011-07-01 2011-07-01 false Overhead and Administrative Costs II(F) Appendix II(F) to Part 13 Money and Finance: Treasury Office of the Secretary of the Treasury... Pt. 13, App. II(F) Appendix II(F) to Part 13—Overhead and Administrative Costs Date: Select Only...

  19. 31 CFR Appendix I(f) to Part 13 - Estimated Overhead and Administrative Costs

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance: Treasury 1 2011-07-01 2011-07-01 false Estimated Overhead and Administrative Costs I(F) Appendix I(F) to Part 13 Money and Finance: Treasury Office of the Secretary of the Treasury... Pt. 13, App. I(F) Appendix I(F) to Part 13—Estimated Overhead and Administrative Costs Date:...

  20. 31 CFR Appendix I(f) to Part 13 - Estimated Overhead and Administrative Costs

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Estimated Overhead and Administrative Costs I(F) Appendix I(F) to Part 13 Money and Finance: Treasury Office of the Secretary of the Treasury... Pt. 13, App. I(F) Appendix I(F) to Part 13—Estimated Overhead and Administrative Costs Date:...

  1. A Guide to the Use of the Overhead Projector. Teaching and Learning in Higher Education, 14.

    ERIC Educational Resources Information Center

    Ellington, Henry

    A sequel to the booklet "A Review of the Different Types of Instructional Materials Available to Teachers and Lecturers," this booklet begins by discussing the main educational uses of the overhead projector and its various strengths and weaknesses. Basic guidelines for using the overhead projector effectively are then offered, which include ways…

  2. 75 FR 81661 - Agency Information Collection Activities; Submission for OMB Review; Comment Request; Overhead...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-28

    ...; Overhead and Gantry Cranes Standard ACTION: Notice. SUMMARY: The Department of Labor (DOL) hereby announces... collection request (ICR) titled, ``Overhead and Gantry Cranes Standard,'' to the Office of Management and... cranes standard specify requirements for: Marking the rated load of cranes; preparing certification...

  3. 30 CFR 57.19110 - Overhead protection for shaft deepening work.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Overhead protection for shaft deepening work... NONMETAL MINES Personnel Hoisting Shafts § 57.19110 Overhead protection for shaft deepening work. A substantial bulkhead or equivalent protection shall be provided above persons at work deepening a shaft....

  4. 30 CFR 56.19110 - Overhead protection for shaft deepening work.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Overhead protection for shaft deepening work... MINES Personnel Hoisting Shafts § 56.19110 Overhead protection for shaft deepening work. A substantial bulkhead or equivalent protection shall be provided above persons at work deepening a shaft....

  5. How To Prepare Effective Overhead Projector Presentations: One Picture Is Worth a Thousand Words.

    ERIC Educational Resources Information Center

    National Audio-Visual Supply, East Rutherford, NJ.

    Designed to help create effective presentations, this guide describes the basic techniques and provides hints for producing professional, attention-getting overhead transparencies in a step-by-step procedure format. Eight topics are addressed in the guide: (1) eight steps to a successful meeting presentation; (2) advantages of overhead projection;…

  6. Kv3.4 channel function and dysfunction in nociceptors

    PubMed Central

    Ritter, David M; Zemel, Benjamin M; Lepore, Angelo C; Covarrubias, Manuel

    2015-01-01

    Recently, we reported the isolation of the Kv3.4 current in dorsal root ganglion (DRG) neurons and described dysregulation of this current in a spinal cord injury (SCI) model of chronic pain. These studies strongly suggest that rat Kv3.4 channels are major regulators of excitability in DRG neurons from pups and adult females, where they help determine action potential (AP) repolarization and spiking properties. Here, we characterized the Kv3.4 current in rat DRG neurons from adult males and show that it transfers 40–70% of the total repolarizing charge during the AP across all ages and sexes. Following SCI, we also found remodeling of the repolarizing currents during the AP. In the light of these studies, homomeric Kv3.4 channels expressed in DRG nociceptors are emerging novel targets that may help develop new approaches to treat neuropathic pain. PMID:26039360

  7. Kv3.4 channel function and dysfunction in nociceptors.

    PubMed

    Ritter, David M; Zemel, Benjamin M; Lepore, Angelo C; Covarrubias, Manuel

    2015-01-01

    Recently, we reported the isolation of the Kv3.4 current in dorsal root ganglion (DRG) neurons and described dysregulation of this current in a spinal cord injury (SCI) model of chronic pain. These studies strongly suggest that rat Kv3.4 channels are major regulators of excitability in DRG neurons from pups and adult females, where they help determine action potential (AP) repolarization and spiking properties. Here, we characterized the Kv3.4 current in rat DRG neurons from adult males and show that it transfers 40-70% of the total repolarizing charge during the AP across all ages and sexes. Following SCI, we also found remodeling of the repolarizing currents during the AP. In the light of these studies, homomeric Kv3.4 channels expressed in DRG nociceptors are emerging novel targets that may help develop new approaches to treat neuropathic pain.

  8. [The story of K.V. Tjellesen].

    PubMed

    Clemmensen, Peter

    2005-01-01

    This is the story about a Danish pharmaceutical wholesaler. The story begins in 1909 in some basement rooms located in Vester Boulevard 42 (which was later to become the Boulevard of H.C. Andersen) in Copenhagen. The founder of the company, pharmacist Knud Valdemar Tjellesen, lived in the very same building. In the beginning, the company mainly sold chemicals and produced and sold chemical-technical products. In 1930, K.V. Tjellesen became the proprietor of the pharmacy Sct. Johannes Apotek situated in Fredensgade 5, Nørrebro in Copenhagen. The company then moved into some offices that were located just behind the pharmacy. Already in 1918, K.V. Tjellesen traded pharmaceutical specialties, which were imported, to a certain extent, from Germany through a purchasing office in Hamburg. In 1938, the son of Knud Valdemar Tjellesen, pharmacist Paul Tjellesen, joined the wholesale company charged with the primary task of intensifying the sale of the company's international agency products. At the same time, the general partnership K.V. Tjellesen was founded. In the time leading up to the Second World War and during this time, business was of course complicated by currency and import restrictions, and it was very difficult to make deliveries to the pharmacies. In Copenhagen, the articles were delivered by 10-12 bicycle delivery boys. In the beginning, the wholesale company mainly catered for Copenhagen and Zealand, but due to the excellent performance of Paul Tjellesen, more and more customers emerged in the rest of the country. In 1954, the company moved to Niels Ebbesens Vej 29 in Frederiksberg given the need for larger facilities. In 1963, an increased space requirement, once again, forced the company to buy one of the neighbouring buildings on Niels Ebbesens Vej and H.C. Orsteds Vej. For many years after, H.C. Orsteds Vej 22 was the official address of the company. After more than 45 years in the company, Paul Tjellesen agreed with his son-in-law Peter Sch

  9. Motor dysfunction and altered synaptic transmission at the parallel fiber-Purkinje cell synapse in mice lacking potassium channels Kv3.1 and Kv3.3.

    PubMed

    Matsukawa, Hiroshi; Wolf, Alexander M; Matsushita, Shinichi; Joho, Rolf H; Knöpfel, Thomas

    2003-08-20

    Micelacking both Kv3.1 and both Kv3.3 K+ channel alleles display severe motor deficits such as tremor, myoclonus, and ataxic gait. Micelacking one to three alleles at the Kv3.1 and Kv3.3 loci exhibit in an allele dose-dependent manner a modest degree of ataxia. Cerebellar granule cells coexpress Kv3.1 and Kv3.3 K+ channels and are therefore candidate neurons that might be involved in these behavioral deficits. Hence, we investigated the synaptic mechanisms of transmission in the parallel fiber-Purkinje cell system. Action potentials of parallel fibers were broader in mice lacking both Kv3.1 and both Kv3.3 alleles and in mice lacking both Kv3.1 and a single Kv3.3 allele compared with those of wild-type mice. The transmission of high-frequency trains of action potentials was only impaired at 200 Hz but not at 100 Hz in mice lacking both Kv3.1 and Kv3.3 genes. However, paired-pulse facilitation (PPF) at parallel fiber-Purkinje cell synapses was dramatically reduced in a gene dose-dependent manner in mice lacking Kv3.1 or Kv3.3 alleles. Normal PPF could be restored by reducing the extracellular Ca2+ concentration indicating that increased activity-dependent presynaptic Ca2+ influx, at least in part caused the altered PPF in mutant mice. Induction of metabotropic glutamate receptor-mediated EPSCs was facilitated, whereas longterm depression was not impaired but rather facilitated in Kv3.1/Kv3.3 double-knockout mice. These results demonstrate the importance of Kv3 potassium channels in regulating the dynamics of synaptic transmission at the parallel fiber-Purkinje cell synapse and suggest a correlation between short-term plasticity at the parallel fiber-Purkinje cell synapse and motor performance.

  10. Allele-dependent changes of olivocerebellar circuit properties in the absence of the voltage-gated potassium channels Kv3.1 and Kv3.3.

    PubMed

    McMahon, Anne; Fowler, Stephen C; Perney, Teresa M; Akemann, Walther; Knöpfel, Thomas; Joho, Rolf H

    2004-06-01

    Double-mutant mice (DKO) lacking the two voltage-gated K(+) channels Kv3.1 and Kv3.3 display a series of phenotypic alterations that include ataxia, myoclonus, tremor and alcohol hypersensitivity. The prominent cerebellar expression of mRNAs encoding Kv3.1 and Kv3.3 subunits raised the question as to whether altered electrical activity resulting from the lack of these K(+) channels might be related to the dramatic motor changes. We used the tremorogenic agent harmaline to probe mutant mice lacking different K(+) channel alleles for altered olivocerebellar circuit properties. Harmaline induced the characteristic 13-Hz tremor in wildtype mice (WT); however, no tremor was observed in DKO suggesting that the ensemble properties of the olivocerebellar circuitry are altered in the absence of Kv3.1 and Kv3.3 subunits. Harmaline induced tremor in Kv3.1-single mutants, but it was of smaller amplitude and at a lower frequency indicating the participation of Kv3.1 subunits in normal olivocerebellar system function. In contrast, harmaline tremor was virtually absent in Kv3.3-single mutants indicating an essential role for Kv3.3 subunits in tremor induction by harmaline. Immunohistochemical staining for Kv3.3 showed clear expression in the somata and proximal dendrites of Purkinje cells and in their axonal projections to the deep cerebellar nuclei (DCN). In DCN, both Kv3.1 and Kv3.3 subunits are expressed. Action potential duration is increased by approximately 100% in Purkinje cells from Kv3.3-single mutants compared to WT or Kv3.1-single mutants. We conclude that Kv3.3 channel subunits are essential for the olivocerebellar system to generate and sustain normal harmaline tremor whereas Kv3.1 subunits influence tremor amplitude and frequency.

  11. Kv7.5 Potassium Channel Subunits Are the Primary Targets for PKA-Dependent Enhancement of Vascular Smooth Muscle Kv7 Currents

    PubMed Central

    Mani, Bharath K.; Robakowski, Christina; Brueggemann, Lyubov I.; Cribbs, Leanne L.; Tripathi, Abhishek; Majetschak, Matthias

    2016-01-01

    Kv7 (KCNQ) channels, formed as homo- or heterotetramers of Kv7.4 and Kv7.5 α-subunits, are important regulators of vascular smooth muscle cell (VSMC) membrane voltage. Recent studies demonstrate that direct pharmacological modulation of VSMC Kv7 channel activity can influence blood vessel contractility and diameter. However, the physiologic regulation of Kv7 channel activity is still poorly understood. Here, we study the effect of cAMP/protein kinase A (PKA) activation on whole cell K+ currents through endogenous Kv7.5 channels in A7r5 rat aortic smooth muscle cells or through Kv7.4/Kv7.5 heteromeric channels natively expressed in rat mesenteric artery smooth muscle cells. The contributions of specific α-subunits are further dissected using exogenously expressed human Kv7.4 and Kv7.5 homo- or heterotetrameric channels in A7r5 cells. Stimulation of Gαs-coupled β-adrenergic receptors with isoproterenol induced PKA-dependent activation of endogenous Kv7.5 currents in A7r5 cells. The receptor-mediated enhancement of Kv7.5 currents was mimicked by pharmacological agents that increase [cAMP] (forskolin, rolipram, 3-isobutyl-1-methylxanthine, and papaverine) or mimic cAMP (8-bromo-cAMP); the 2- to 4-fold PKA-dependent enhancement of currents was also observed with exogenously expressed Kv7.5 channels. In contrast, exogenously-expressed heterotetrameric Kv7.4/7.5 channels in A7r5 cells or native mesenteric artery smooth muscle Kv7.4/7.5 channels were only modestly enhanced, and homo-tetrameric Kv7.4 channels were insensitive to this regulatory pathway. Correspondingly, proximity ligation assays indicated that isoproterenol induced PKA-dependent phosphorylation of exogenously expressed Kv7.5 channel subunits, but not of Kv7.4 subunits. These results suggest that signal transduction-mediated responsiveness of vascular smooth muscle Kv7 channel subunits to cAMP/PKA activation follows the order of Kv7.5 >> Kv7.4/Kv7.5 > Kv7.4. PMID:26700561

  12. Overhead camshaft engine valve train with slack take up means

    SciTech Connect

    Hayashi, Y.

    1987-03-03

    A valve train of an overhead camshaft engine is described comprising: a valve stem; a valve operating cam; a rocker arm operatively engaged with the valve stem and the cam for transferring motion from the cam to the valve stem and having at a part where it is operatively engaged with the cam a hole; a tappet reciprocatingly mounted in the hole in a manner to define an oil pressure chamber variable in volume in accordance with actual movement of the tappet and having an end protruding from the rocker arm to contact the cam; a source of pressurized oil; passageway means for providing communication between the source of pressurized oil and the oil pressure chamber; check valve means operatively connected with the passageway means for preventing a return flow out of the oil pressure chamber; a spring disposed in the oil pressure chamber to urge the tappet in the direction causing the oil pressure chamber to increase in volume to thereby take up slack in the valve train; and an oil releasing passageway having one end opening directly into the uppermost part of the oil pressure chamber and another end opening to the outside of the rocker arm.

  13. Soft-light overhead illumination systems improve laparoscopic task performance.

    PubMed

    Takai, Akihiro; Takada, Yasutsugu; Motomura, Hideki; Teramukai, Satoshi

    2014-02-01

    The aim of this study was to evaluate the impact of attached shadow cues for laparoscopic task performance. We developed a soft-light overhead illumination system (SOIS) that produced attached shadows on objects. We compared results using the SOIS with those using a conventional illumination system with regard to laparoscopic experience and laparoscope-to-target distances (LTDs). Forty-two medical students and 23 surgeons participated in the study. A peg transfer task (LTD, 120 mm) for students and surgeons, and a suture removal task (LTD, 30 mm) for students were performed. Illumination systems were randomly assigned to each task. Endpoints were: total number of peg transfers; percentage of peg-dropping errors; and total execution time for suture removal. After the task, participants filled out a questionnaire on their preference for a particular illumination system. Total number of peg transfers was greater with the SOIS for both students and surgeons. Percentage of peg-dropping errors for surgeons was lower with the SOIS. Total execution time for suture removal was shorter with the SOIS. Forty-five participants (69% in total) evaluated the SOIS for easier task performance. The present results confirm that the SOIS improves laparoscopic task performance, regardless of previous laparoscopic experience or LTD.

  14. Kv1.5 in the Immune System: the Good, the Bad, or the Ugly?

    PubMed Central

    Felipe, Antonio; Soler, Concepció; Comes, Núria

    2010-01-01

    For the last 20 years, knowledge of the physiological role of voltage-dependent potassium channels (Kv) in the immune system has grown exponentially. Leukocytes express a limited repertoire of Kv channels, which contribute to the membrane potential. These proteins are involved in the immune response and are therefore considered good pharmacological targets. Although there is a clear consensus about the physiological relevance of Kv1.3, the expression and the role of Kv1.5 are controversial. However, recent reports indicate that certain heteromeric Kv1.3/Kv1.5 associations may provide insight on Kv1.5. Here, we summarize what is known about this issue and highlight the role of Kv1.5 partnership interactions that could be responsible for this debate. The Kv1.3/Kv1.5 heterotetrameric composition of the channel and their possible differential associations with accessory regulatory proteins warrant further investigation. PMID:21423392

  15. Fatigue during prolonged intermittent overhead work: reliability of measures and effects of working height.

    PubMed

    Sood, Deepti; Nussbaum, Maury A; Hager, Kris

    2007-04-01

    Shoulder pain is prevalent among industrial workers and existing evidence supports that overhead work is an important specific risk factor. Existing guidelines are limited, with overhead work typically recommended to be avoided, and research on overhead work has been mixed in terms of the effects of increasing arm reach. A laboratory-based simulation of overhead work was conducted, at three working heights, in order to facilitate improved guidelines and to identify potential non-linear effects of overhead work height. Several indicators of shoulder fatigue served as outcome measures and a preliminary study was performed to assess the reliability of several of these measures. Fatigue measures based on electromyography (EMG) generally had low reliability, whereas excellent reliability was exhibited for ratings of perceived discomfort (RPD). Consistent with this, no effects of overhead work height were found on EMG-based measures, yet clear non-linear effects were found on RPD and task performance. The source of the effects of work height appeared to be related to a combination of muscle activation levels and demands on precision/control at the highest location. These results support the utility of subjective measures for relatively low-level intermittent exertions and demonstrate increasingly detrimental fatigue and performance effects at extremes in reach during overhead work.

  16. 29 CFR 1926.1003 - Overhead protection for operators of agricultural and industrial tractors used in construction.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... REGULATIONS FOR CONSTRUCTION Rollover Protective Structures; Overhead Protection § 1926.1003 Overhead...) Purpose. When overhead protection is provided on wheel-type agricultural and industrial tractors, the... accidental upset. (2) Applicability. This standard applies to wheel-type agricultural and industrial...

  17. 29 CFR 1926.1003 - Overhead protection for operators of agricultural and industrial tractors used in construction.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... REGULATIONS FOR CONSTRUCTION Rollover Protective Structures; Overhead Protection § 1926.1003 Overhead...) Purpose. When overhead protection is provided on wheel-type agricultural and industrial tractors, the... accidental upset. (2) Applicability. This standard applies to wheel-type agricultural and industrial...

  18. 29 CFR 1926.1003 - Overhead protection for operators of agricultural and industrial tractors used in construction.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... REGULATIONS FOR CONSTRUCTION Rollover Protective Structures; Overhead Protection § 1926.1003 Overhead...) Purpose. When overhead protection is provided on wheel-type agricultural and industrial tractors, the... accidental upset. (2) Applicability. This standard applies to wheel-type agricultural and industrial...

  19. 29 CFR 1926.1003 - Overhead protection for operators of agricultural and industrial tractors used in construction.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... REGULATIONS FOR CONSTRUCTION Rollover Protective Structures; Overhead Protection § 1926.1003 Overhead...) Purpose. When overhead protection is provided on wheel-type agricultural and industrial tractors, the... accidental upset. (2) Applicability. This standard applies to wheel-type agricultural and industrial...

  20. 78 FR 68477 - Overhead and Gantry Cranes; Extension of the Office of Management and Budget's (OMB) Approval of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-14

    ... Occupational Safety and Health Administration Overhead and Gantry Cranes; Extension of the Office of Management...) approval of the information collection requirements specified in the Standard on Overhead and Gantry Cranes... Standard on Overhead and Gantry Cranes specify requirements for: Marking the rated load of cranes; and...

  1. Kv3.1b and Kv3.3 channel subunit expression in murine spinal dorsal horn GABAergic interneurones.

    PubMed

    Nowak, A; Mathieson, H R; Chapman, R J; Janzsó, G; Yanagawa, Y; Obata, K; Szabo, G; King, A E

    2011-09-01

    GABAergic interneurones, including those within spinal dorsal horn, contain one of the two isoforms of the synthesizing enzyme glutamate decarboxylase (GAD), either GAD65 or GAD67. The physiological significance of these two GABAergic phenotypes is unknown but a more detailed anatomical and functional characterization may help resolve this issue. In this study, two transgenic Green Fluorescent Protein (GFP) knock-in murine lines, namely GAD65-GFP and GAD67-GFP (Δneo) mice, were used to profile expression of Shaw-related Kv3.1b and Kv3.3 K(+)-channel subunits in dorsal horn interneurones. Neuronal expression of these subunits confers specific biophysical characteristic referred to as 'fast-spiking'. Immuno-labelling for Kv3.1b or Kv3.3 revealed the presence of both of these subunits across the dorsal horn, most abundantly in laminae I-III. Co-localization studies in transgenic mice indicated that Kv3.1b but not Kv3.3 was associated with GAD65-GFP and GAD67-GFP immunopositive neurones. For comparison the distributions of Kv4.2 and Kv4.3 K(+)-channel subunits which are linked to an excitatory neuronal phenotype were characterized. No co-localization was found between GAD-GFP +ve neurones and Kv4.2 or Kv4.3. In functional studies to evaluate whether either GABAergic population is activated by noxious stimulation, hindpaw intradermal injection of capsaicin followed by c-fos quantification in dorsal horn revealed co-expression c-fos and GAD65-GFP (quantified as 20-30% of GFP +ve population). Co-expression was also detected for GAD67-GFP +ve neurones and capsaicin-induced c-fos but at a much reduced level of 4-5%. These data suggest that whilst both GAD65-GFP and GAD67-GFP +ve neurones express Kv3.1b and therefore may share certain biophysical traits, their responses to peripheral noxious stimulation are distinct.

  2. Postnatal development of A-type and Kv1- and Kv2-mediated potassium channel currents in neocortical pyramidal neurons

    PubMed Central

    Guan, Dongxu; Horton, Leslie R.; Armstrong, William E.

    2011-01-01

    Potassium channels regulate numerous aspects of neuronal excitability, and several voltage-gated K+ channel subunits have been identified in pyramidal neurons of rat neocortex. Previous studies have either considered the development of outward current as a whole or divided currents into transient, A-type and persistent, delayed rectifier components but did not differentiate between current components defined by α-subunit type. To facilitate comparisons of studies reporting K+ currents from animals of different ages and to understand the functional roles of specific current components, we characterized the postnatal development of identified Kv channel-mediated currents in pyramidal neurons from layers II/III from rat somatosensory cortex. Both the persistent/slowly inactivating and transient components of the total K+ current increased in density with postnatal age. We used specific pharmacological agents to test the relative contributions of putative Kv1- and Kv2-mediated currents (100 nM α-dendrotoxin and 600 nM stromatoxin, respectively). A combination of voltage protocol, pharmacology, and curve fitting was used to isolate the rapidly inactivating A-type current. We found that the density of all identified current components increased with postnatal age, approaching a plateau at 3–5 wk. We found no significant changes in the relative proportions or kinetics of any component between postnatal weeks 1 and 5, except that the activation time constant for A-type current was longer at 1 wk. The putative Kv2-mediated component was the largest at all ages. Immunocytochemistry indicated that protein expression for Kv4.2, Kv4.3, Kv1.4, and Kv2.1 increased between 1 wk and 4–5 wk of age. PMID:21451062

  3. Current Concepts in the Evaluation and Treatment of the Shoulder in Overhead Throwing Athletes, Part 2

    PubMed Central

    Reinold, Michael M.; Gill, Thomas J.; Wilk, Kevin E.; Andrews, James R.

    2010-01-01

    The overhead throwing athlete is an extremely challenging patient in sports medicine. The repetitive microtraumatic stresses imposed on the athlete’s shoulder joint complex during the throwing motion constantly place the athlete at risk for injury. Treatment of the overhead athlete requires the understanding of several principles based on the unique physical characteristics of the overhead athlete and the demands endured during the act of throwing. These principles are described and incorporated in a multiphase progressive rehabilitation program designed to prevent injuries and rehabilitate the injured athlete, both nonoperatively and postoperatively. PMID:23015928

  4. Novel Kv3 glycoforms differentially expressed in adult mammalian brain contain sialylated N-glycans.

    PubMed

    Schwalbe, Ruth A; Corey, Melissa J; Cartwright, Tara A

    2008-02-01

    The N-glycan pool of mammalian brain contains remarkably high levels of sialylated N-glycans. This study provides the first evidence that voltage-gated K+ channels Kv3.1, Kv3.3, and Kv3.4, possess distinct sialylated N-glycan structures throughout the central nervous system of the adult rat. Electrophoretic migration patterns of Kv3.1, Kv3.3, and Kv3.4 glycoproteins from spinal cord, hypothalamus, thalamus, cerebral cortex, hippocampus, and cerebellum membranes digested with glycosidases were used to identify the various glycoforms. Differences in the migration of Kv3 proteins were attributed to the desialylated N-glycans. Expression levels of the Kv3 proteins were highest in cerebellum, whereas those of Kv3.1 and Kv3.3 were much lower in the other 5 regions. The lowest level of Kv3.1 was expressed in the hypothalamus, whereas the lowest levels of Kv3.3 were expressed in both thalamus and hypothalamus. The other regions expressed intermediate levels of Kv3.3, with spinal cord expressing the highest. The expression level of Kv3.4 in the hippocampus was slightly lower than that in cerebellum, and was closely followed by the other 4 regions, with spinal cord expressing the lowest level. We suggest that novel Kv3 glycoforms may endow differences in channel function and expression among regions throughout the central nervous system.

  5. Protein Kinase C (PKC) Activity Regulates Functional Effects of Kvβ1.3 Subunit on KV1.5 Channels

    PubMed Central

    David, Miren; Macías, Álvaro; Moreno, Cristina; Prieto, Ángela; Martínez-Mármol, Ramón; Vicente, Rubén; González, Teresa; Felipe, Antonio; Tamkun, Michael M.; Valenzuela, Carmen

    2012-01-01

    Kv1.5 channels are the primary channels contributing to the ultrarapid outward potassium current (IKur). The regulatory Kvβ1.3 subunit converts Kv1.5 channels from delayed rectifiers with a modest degree of slow inactivation to channels with both fast and slow inactivation components. Previous studies have shown that inhibition of PKC with calphostin C abolishes the fast inactivation induced by Kvβ1.3. In this study, we investigated the mechanisms underlying this phenomenon using electrophysiological, biochemical, and confocal microscopy approaches. To achieve this, we used HEK293 cells (which lack Kvβ subunits) transiently cotransfected with Kv1.5+Kvβ1.3 and also rat ventricular and atrial tissue to study native α-β subunit interactions. Immunocytochemistry assays demonstrated that these channel subunits colocalize in control conditions and after calphostin C treatment. Moreover, coimmunoprecipitation studies showed that Kv1.5 and Kvβ1.3 remain associated after PKC inhibition. After knocking down all PKC isoforms by siRNA or inhibiting PKC with calphostin C, Kvβ1.3-induced fast inactivation at +60 mV was abolished. However, depolarization to +100 mV revealed Kvβ1.3-induced inactivation, indicating that PKC inhibition causes a dramatic positive shift of the inactivation curve. Our results demonstrate that calphostin C-mediated abolishment of fast inactivation is not due to the dissociation of Kv1.5 and Kvβ1.3. Finally, immunoprecipitation and immunocytochemistry experiments revealed an association between Kv1.5, Kvβ1.3, the receptor for activated C kinase (RACK1), PKCβI, PKCβII, and PKCθ in HEK293 cells. A very similar Kv1.5 channelosome was found in rat ventricular tissue but not in atrial tissue. PMID:22547057

  6. MinK, MiRP1, and MiRP2 diversify Kv3.1 and Kv3.2 potassium channel gating.

    PubMed

    Lewis, Anthony; McCrossan, Zoe A; Abbott, Geoffrey W

    2004-02-27

    High frequency firing in mammalian neurons requires ultra-rapid delayed rectifier potassium currents generated by homomeric or heteromeric assemblies of Kv3.1 and Kv3.2 potassium channel alpha subunits. Kv3.1 alpha subunits can also form slower activating channels by coassembling with MinK-related peptide 2 (MiRP2), a single transmembrane domain potassium channel ancillary subunit. Here, using channel subunits cloned from rat and expressed in Chinese hamster ovary cells, we show that modulation by MinK, MiRP1, and MiRP2 is a general mechanism for slowing of Kv3.1 and Kv3.2 channel activation and deactivation and acceleration of inactivation, creating a functionally diverse range of channel complexes. MiRP1 also negatively shifts the voltage dependence of Kv3.1 and Kv3.2 channel activation. Furthermore, MinK, MiRP1, and MiRP2 each form channels with Kv3.1-Kv3.2 heteromers that are kinetically distinct from one another and from MiRP/homomeric Kv3 channels. The findings illustrate a mechanism for dynamic expansion of the functional repertoire of Kv3.1 and Kv3.2 potassium currents and suggest roles for these alpha subunits outside the scope of sustained rapid neuronal firing.

  7. Headgear Accessories Classification Using an Overhead Depth Sensor

    PubMed Central

    Luna, Carlos A.; Marron-Romera, Marta; Mazo, Manuel; Luengo-Sanchez, Sara; Macho-Pedroso, Roberto

    2017-01-01

    In this paper, we address the generation of semantic labels describing the headgear accessories carried out by people in a scene under surveillance, only using depth information obtained from a Time-of-Flight (ToF) camera placed in an overhead position. We propose a new method for headgear accessories classification based on the design of a robust processing strategy that includes the estimation of a meaningful feature vector that provides the relevant information about the people’s head and shoulder areas. This paper includes a detailed description of the proposed algorithmic approach, and the results obtained in tests with persons with and without headgear accessories, and with different types of hats and caps. In order to evaluate the proposal, a wide experimental validation has been carried out on a fully labeled database (that has been made available to the scientific community), including a broad variety of people and headgear accessories. For the validation, three different levels of detail have been defined, considering a different number of classes: the first level only includes two classes (hat/cap, and no hat/cap), the second one considers three classes (hat, cap and no hat/cap), and the last one includes the full class set with the five classes (no hat/cap, cap, small size hat, medium size hat, and large size hat). The achieved performance is satisfactory in every case: the average classification rates for the first level reaches 95.25%, for the second one is 92.34%, and for the full class set equals 84.60%. In addition, the online stage processing time is 5.75 ms per frame in a standard PC, thus allowing for real-time operation. PMID:28796177

  8. Structural health monitoring of compression connectors for overhead transmission lines

    SciTech Connect

    Wang, Hong; Wang, Jy-An John; Swindeman, Joseph P; Ren, Fei; Chan, John

    2017-01-01

    Two-stage aluminum conductor steel-reinforced (ACSR) compression connectors are extensively used in US overhead transmission lines. The connectors are made by crimping a steel sleeve onto a steel core and an aluminum sleeve over aluminum conductive strands. The connectors are designed to operate at temperatures up to 125 C, but their performance is increasingly degrading because of overloading of lines. Currently, electric utilities conduct routine line inspections using thermal and electrical measurements. However, information about the structural integrity of connectors cannot be obtained. In this work, structural health monitoring (SHM) of compression connectors was studied using electromechanical impedance (EMI) analysis. Lead zirconate titanate (PZT)-5A was identified as a smart material for SHM. A flexible high-temperature bonding layer was used to address challenges in PZT integration due to a significant difference in the coefficients of thermal expansion of PZT and the aluminum substrate. The steel joint on the steel core was investigated because it is responsible for the ultimate tensile strength of the connector. Tensile testing was used to create structural damage to the joint, or steel core pullout, and thermal cycling introduced additional structural perturbations. EMI measurements were conducted between the tests. The root mean square deviation (RMSD) of EMI was identified as a damage index. The use of steel joints has been shown to enable SHM under simulated conditions. The EMI signature is sensitive to variations in structural conditions. RMSD can be correlated to the structural health of a connector and has potential for use in the SHM and structural integrity evaluation.

  9. Predicting ice accretion and alleviating galloping on overhead power lines

    NASA Astrophysics Data System (ADS)

    Lu, Mingliang

    2002-04-01

    Both the static and dynamic effects of an ice storm on an overhead power line are investigated fairly comprehensively in this thesis. To determine the static, extreme ice load as well as the combined ice and wind load, a systematic procedure is established based on extensive freezing rain experiments and a Monte Carlo simulation. On the other hand, a dynamic effect---galloping---is examined quite extensively with the objective of better understanding its behavior. A novel add-on device---the hybrid nutation damper (HND)---is proposed to control galloping. Its effectiveness is assessed numerically by using a modified, 3DOF based, galloping software. The present investigations lead to the following findings. (i) Goodwin's simple theoretical model surprisingly predicts, quite accurately, the temporally changing weight of not only a dry ice growth but also a wet ice growth for a fixed, unheated conductor sample. (ii) The maximum ice loading may vary significantly over a power line's planned lifetime because of the randomness of an ice storm and its characteristics as well as the uncertainty involved in identifying the extreme probability distribution of the ice loading. Consequently, backup protection is presently essential for a power line in an ice prone area. (iii) A conductor's torsional flexibility does not appear to affect the growth of the accreted ice weight but it modifies the ice shape significantly. (iv) Three representative ice shapes (a crescent, D-like and icicle pendant) can initiate galloping so that galloping may occur in any icing condition. (v) A noticeable swingback or twist appears to develop only when their respective natural frequencies coincide with the plunge's natural frequency. (vi) A hydraulic jump is the major source of energy dissipation in a nutation damper. A properly induced rotation can significantly enhance a nutation damper's performance. (vii) A hybrid nutation damper has been demonstrated to be a promising means of alleviating

  10. Structural health monitoring of compression connectors for overhead transmission lines

    NASA Astrophysics Data System (ADS)

    Wang, Hong; Wang, Jy-An John; Swindeman, Joseph P.; Ren, Fei; Chan, John

    2017-04-01

    Two-stage aluminum conductor steel-reinforced (ACSR) compression connectors are extensively used in US overhead transmission lines. The connectors are made by crimping a steel sleeve onto a steel core and an aluminum sleeve over electrical conducting aluminum strands. The connectors are designed to operate at temperatures up to 125°C, but their performance is increasingly degrading because of overloading of lines. Currently, electric utilities conduct routine line inspections using thermal and electrical measurements, but these methods do not provide information about the structural integrity of connectors. In this work, structural health monitoring (SHM) of compression connectors was studied using electromechanical impedance (EMI) analysis. Lead zirconate titanate (PZT)-5A was identified as a smart material for SHM. A flexible high-temperature bonding layer was used to address challenges in PZT integration due to a significant difference in the coefficients of thermal expansion of PZT and the aluminum substrate. The steel joint on the steel core was investigated because it is responsible for the ultimate tensile strength of the connector. Tensile testing was used to induce structural damage to the joint, or steel core pullout, and thermal cycling introduced additional structural perturbations. EMI measurements were conducted between the tests. The root mean square deviation (RMSD) of EMI was identified as a damage index. The use of steel joints has been shown to enable SHM under simulated conditions. The EMI signature is sensitive to variations in structural conditions. RMSD can be correlated to the structural health of a connector and has potential for use in the SHM and structural integrity evaluation.

  11. Headgear Accessories Classification Using an Overhead Depth Sensor.

    PubMed

    Luna, Carlos A; Macias-Guarasa, Javier; Losada-Gutierrez, Cristina; Marron-Romera, Marta; Mazo, Manuel; Luengo-Sanchez, Sara; Macho-Pedroso, Roberto

    2017-08-10

    In this paper, we address the generation of semantic labels describing the headgear accessories carried out by people in a scene under surveillance, only using depth information obtained from a Time-of-Flight (ToF) camera placed in an overhead position. We propose a new method for headgear accessories classification based on the design of a robust processing strategy that includes the estimation of a meaningful feature vector that provides the relevant information about the people's head and shoulder areas. This paper includes a detailed description of the proposed algorithmic approach, and the results obtained in tests with persons with and without headgear accessories, and with different types of hats and caps. In order to evaluate the proposal, a wide experimental validation has been carried out on a fully labeled database (that has been made available to the scientific community), including a broad variety of people and headgear accessories. For the validation, three different levels of detail have been defined, considering a different number of classes: the first level only includes two classes (hat/cap, and no hat/cap), the second one considers three classes (hat, cap and no hat/cap), and the last one includes the full class set with the five classes (no hat/cap, cap, small size hat, medium size hat, and large size hat). The achieved performance is satisfactory in every case: the average classification rates for the first level reaches 95.25%, for the second one is 92.34%, and for the full class set equals 84.60%. In addition, the online stage processing time is 5.75 ms per frame in a standard PC, thus allowing for real-time operation.

  12. Kv2 subunits underlie slowly inactivating potassium current in rat neocortical pyramidal neurons

    PubMed Central

    Guan, D; Tkatch, T; Surmeier, D J; Armstrong, W E; Foehring, R C

    2007-01-01

    We determined the expression of Kv2 channel subunits in rat somatosensory and motor cortex and tested for the contributions of Kv2 subunits to slowly inactivating K+ currents in supragranular pyramidal neurons. Single cell RT-PCR showed that virtually all pyramidal cells expressed Kv2.1 mRNA and ∼80% expressed Kv2.2 mRNA. Immunocytochemistry revealed striking differences in the distribution of Kv2.1 and Kv2.2 subunits. Kv2.1 subunits were clustered and located on somata and proximal dendrites of all pyramidal cells. Kv2.2 subunits were primarily distributed on large apical dendrites of a subset of pyramidal cells from deep layers. We used two methods for isolating currents through Kv2 channels after excluding contributions from Kv1 subunits: intracellular diffusion of Kv2.1 antibodies through the recording pipette and extracellular application of rStromatoxin-1 (ScTx). The Kv2.1 antibody specifically blocked the slowly inactivating K+ current by 25–50% (at 8 min), demonstrating that Kv2.1 subunits underlie much of this current in neocortical pyramidal neurons. ScTx (300 nm) also inhibited ∼40% of the slowly inactivating K+ current. We observed occlusion between the actions of Kv2.1 antibody and ScTx. In addition, Kv2.1 antibody- and ScTx-sensitive currents demonstrated similar recovery from inactivation and voltage dependence and kinetics of activation and inactivation. These data indicate that both agents targeted the same channels. Considering the localization of Kv2.1 and 2.2 subunits, currents from truncated dissociated cells are probably dominated by Kv2.1 subunits. Compared with Kv2.1 currents in expression systems, the Kv2.1 current in neocortical pyramidal cells activated and inactivated at relatively negative potentials and was very sensitive to holding potential. PMID:17379638

  13. Steel tanks T5 and T4 with overhead pipeline between. Redwood ...

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

    Steel tanks T5 and T4 with overhead pipeline between. Redwood tanks seen in background - Hawaii Volcanoes National Park Water Collection System, Hawaii Volcanoes National Park, Volcano, Hawaii County, HI

  14. DETAIL OVERHEAD VIEW OF SECONDARY ORE BIN, CONVEYOR PLATFORM,TRAM TRESTLE, ...

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

    DETAIL OVERHEAD VIEW OF SECONDARY ORE BIN, CONVEYOR PLATFORM,TRAM TRESTLE, LOADING PLATFORM, AND BOILER, LOOKING SOUTHEAST. - Keane Wonder Mine, Park Route 4 (Daylight Pass Cutoff), Death Valley Junction, Inyo County, CA

  15. Detail, cyclops 15ton overhead traveling crane and rails running the ...

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

    Detail, cyclops 15-ton overhead traveling crane and rails running the length of the building - Wellton-Mohawk Irrigation System, Pumping Plant No. 1, Bounded by Gila River & Union Pacific Railroad, Wellton, Yuma County, AZ

  16. 15. VIEW OF THE ORIGINAL 10TON OVERHEAD NILES TRAVELING CRANE. ...

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

    15. VIEW OF THE ORIGINAL 10-TON OVERHEAD NILES TRAVELING CRANE. - Washington Water Power Company Post Falls Power Plant, Middle Channel Powerhouse & Dam, West of intersection of Spokane & Fourth Streets, Post Falls, Kootenai County, ID

  17. Detail, 25ton overhead traveling crane built by The Craneveyor Corporation, ...

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

    Detail, 25-ton overhead traveling crane built by The Craneveyor Corporation, Los Angeles, California - Wellton-Mohawk Irrigation System, Pumping Plant No. 3, South of Interstate 8, Wellton, Yuma County, AZ

  18. Skeletal muscle Kv7 (KCNQ) channels in myoblast differentiation and proliferation

    SciTech Connect

    Roura-Ferrer, Meritxell; Sole, Laura; Martinez-Marmol, Ramon; Villalonga, Nuria; Felipe, Antonio

    2008-05-16

    Voltage-dependent K{sup +} channels (Kv) are involved in myocyte proliferation and differentiation by triggering changes in membrane potential and regulating cell volume. Since Kv7 channels may participate in these events, the purpose of this study was to investigate whether skeletal muscle Kv7.1 and Kv7.5 were involved during proliferation and myogenesis. Here we report that, while myotube formation did not regulate Kv7 channels, Kv7.5 was up-regulated during cell cycle progression. Although, Kv7.1 mRNA also increased during the G{sub 1}-phase, pharmacological evidence mainly involves Kv7.5 in myoblast growth. Our results indicate that the cell cycle-dependent expression of Kv7.5 is involved in skeletal muscle cell proliferation.

  19. Calculation of induced voltages on overhead lines caused by inclined lightning strokes

    SciTech Connect

    Sakakibara, A.

    1989-01-01

    Equations to calculate the inducing scalar and vector potentials produced by inclined return strokes are shown. Equations are also shown for calculating the induced voltages on overhead lines where horizontal components of inducing vector potential exist. The adequacy of the calculation method is demonstrated by field experiments. Using these equations, induced voltages on overhead lines are calculated for a variety of directions of return strokes.

  20. [Current concepts in the diagnosis and rehabilitation of the shoulder in overhead athletes].

    PubMed

    Gokeler, A; Lehmann, M; Knopf, E; Freiwald, J

    2003-03-01

    The purpose of this paper is to present the general guidelines, including implementation of principles of motor learning in the course of the rehabilitation of the shoulder in overhead athletes. The focus is on treating the most common injury pattern of overhead athletes being rotator cuff pathology with secondary bursitis and finally microtraumatic instability. Specific criteria are discussed to determine when the athlete can return to unrestricted sport participation.

  1. Comparison of Civilian and Military Overhead Spending: Three Case Studies. Revision.

    DTIC Science & Technology

    1984-09-17

    aDesignations used by the Defense Housing Management Systems Office. TABLE 4 CIVILIAN HOUSING MAINTENANCE SPENDING VS. AGEa (Single unit, owner occupied...I-t9 ONCOMlPARISON OF CIVILIRN iND MILITARY OVERHEAD SPENDING : ,l THREE CASE STUDIES.. (U) CENTER FOR NAVAL ANALYSES RLEXADRIA YR NAVAL PLRNNING RND...ftFL RESEARCH MEMORANDUM 0 COMPARISON OF CIVILIAN AND MILITARY OVERHEAD SPENDING : I THREE CASE STUDIES Daniel B. Levine Colin P. Hammon DTIC ELECTE K

  2. Kv3.3 potassium channels and spinocerebellar ataxia.

    PubMed

    Zhang, Yalan; Kaczmarek, Leonard K

    2016-08-15

    The voltage-dependent potassium channel subunit Kv3.3 is expressed at high levels in cerebellar Purkinje cells, in auditory brainstem nuclei and in many other neurons capable of firing at high rates. In the cerebellum, it helps to shape the very characteristic complex spike of Purkinje cells. Kv3.3 differs from other closely related channels in that human mutations in the gene encoding Kv3.3 (KCNC3) result in a unique neurodegenerative disease termed spinocerebellar ataxia type 13 (SCA13). This primarily affects the cerebellum, but also results in extracerebellar symptoms. Different mutations produce either early onset SCA13, associated with delayed motor and impaired cognitive skill acquisition, or late onset SCA13, which typically produces cerebellar degeneration in middle age. This review covers the localization and physiological function of Kv3.3 in the central nervous system and how the normal function of the channel is altered by the disease-causing mutations. It also describes experimental approaches that are being used to understand how Kv3.3 mutations are linked to neuronal survival, and to develop strategies for treatment.

  3. A New Kv1.2 Channelopathy Underlying Cerebellar Ataxia*

    PubMed Central

    Xie, Gang; Harrison, John; Clapcote, Steven J.; Huang, Yun; Zhang, Jin-Yi; Wang, Lu-Yang; Roder, John C.

    2010-01-01

    A forward genetic screen of mice treated with the mutagen ENU identified a mutant mouse with chronic motor incoordination. This mutant, named Pingu (Pgu), carries a missense mutation, an I402T substitution in the S6 segment of the voltage-gated potassium channel Kcna2. The gene Kcna2 encodes the voltage-gated potassium channel α-subunit Kv1.2, which is abundantly expressed in the large axon terminals of basket cells that make powerful axo-somatic synapses onto Purkinje cells. Patch clamp recordings from cerebellar slices revealed an increased frequency and amplitude of spontaneous GABAergic inhibitory postsynaptic currents and reduced action potential firing frequency in Purkinje cells, suggesting that an increase in GABA release from basket cells is involved in the motor incoordination in Pgu mice. In line with immunochemical analyses showing a significant reduction in the expression of Kv1 channels in the basket cell terminals of Pgu mice, expression of homomeric and heteromeric channels containing the Kv1.2(I402T) α-subunit in cultured CHO cells revealed subtle changes in biophysical properties but a dramatic decrease in the amount of functional Kv1 channels. Pharmacological treatment with acetazolamide or transgenic complementation with wild-type Kcna2 cDNA partially rescued the motor incoordination in Pgu mice. These results suggest that independent of known mutations in Kcna1 encoding Kv1.1, Kcna2 mutations may be important molecular correlates underlying human cerebellar ataxic disease. PMID:20696761

  4. A new Kv1.2 channelopathy underlying cerebellar ataxia.

    PubMed

    Xie, Gang; Harrison, John; Clapcote, Steven J; Huang, Yun; Zhang, Jin-Yi; Wang, Lu-Yang; Roder, John C

    2010-10-15

    A forward genetic screen of mice treated with the mutagen ENU identified a mutant mouse with chronic motor incoordination. This mutant, named Pingu (Pgu), carries a missense mutation, an I402T substitution in the S6 segment of the voltage-gated potassium channel Kcna2. The gene Kcna2 encodes the voltage-gated potassium channel α-subunit Kv1.2, which is abundantly expressed in the large axon terminals of basket cells that make powerful axo-somatic synapses onto Purkinje cells. Patch clamp recordings from cerebellar slices revealed an increased frequency and amplitude of spontaneous GABAergic inhibitory postsynaptic currents and reduced action potential firing frequency in Purkinje cells, suggesting that an increase in GABA release from basket cells is involved in the motor incoordination in Pgu mice. In line with immunochemical analyses showing a significant reduction in the expression of Kv1 channels in the basket cell terminals of Pgu mice, expression of homomeric and heteromeric channels containing the Kv1.2(I402T) α-subunit in cultured CHO cells revealed subtle changes in biophysical properties but a dramatic decrease in the amount of functional Kv1 channels. Pharmacological treatment with acetazolamide or transgenic complementation with wild-type Kcna2 cDNA partially rescued the motor incoordination in Pgu mice. These results suggest that independent of known mutations in Kcna1 encoding Kv1.1, Kcna2 mutations may be important molecular correlates underlying human cerebellar ataxic disease.

  5. Functional Multijoint Position Reproduction Acuity in Overhead-Throwing Athletes

    PubMed Central

    Tripp, Brady L; Uhl, Timothy L; Mattacola, Carl G; Srinivasan, Cidambi; Shapiro, Robert

    2006-01-01

    Context: Baseball players rely on the sensorimotor system to uphold the balance between upper extremity stability and mobility while maintaining athletic performance. However, few researchers have studied functional multijoint measures of sensorimotor acuity in overhead-throwing athletes. Objective: To compare sensorimotor acuity between 2 high-demand functional positions and among planes of motion within individual joints and to describe a novel method of measuring sensorimotor function. Design: Single-session, repeated-measures design. Setting: University musculoskeletal research laboratory. Patients or Other Participants: Twenty-one National Collegiate Athletic Association Division I baseball players (age = 20.8 ± 1.5 years, height = 181.3 ± 5.1 cm, mass = 87.8 ± 9.1 kg) with no history of upper extremity injury or central nervous system disorder. Main Outcome Measure(s): We measured active multijoint position reproduction acuity in multiple planes using an electromagnetic tracking device. Subjects reproduced 2 positions: arm cock and ball release. We calculated absolute and variable error for individual motions at the scapulothoracic, glenohumeral, elbow, and wrist joints and calculated overall joint acuity with 3-dimensional variable error. Results: Acuity was significantly better in the arm-cock position compared with ball release at the scapulothoracic and glenohumeral joints. We observed significant differences among planes of motion within the scapulothoracic and glenohumeral joints at ball release. Scapulothoracic internal rotation and glenohumeral horizontal abduction and rotation displayed less acuity than other motions. Conclusions: We established the reliability of a functional measure of upper extremity sensorimotor system acuity in baseball players. Using this technique, we observed differences in acuity between 2 test positions and among planes of motion within the glenohumeral and scapulothoracic joints. Clinicians may consider these

  6. Adaptations of the Shoulder to Overhead Throwing in Youth Athletes

    PubMed Central

    Astolfi, Matthew Michael; Struminger, Aaron H.; Royer, Todd D.; Kaminski, Thomas W.; Swanik,, Charles B.

    2015-01-01

    Context The high number of repetitions and high forces associated with overhead throwing lead to anatomical adaptations, such as humeral retrotorsion and posterior-capsule thickness, in elite and professional baseball athletes. However, little is known about the origin and progression of these changes that may account for the increasing trend of chronic shoulder injuries in youth baseball and precipitate subsequent pathologic conditions throughout a young athlete's lifetime. Objective To investigate the relationship of age and upper extremity dominance on humeral retrotorsion, posterior-capsule thickness, and glenohumeral range of motion. Design Cross-sectional study. Setting Research laboratory, local baseball fields, and training facilities. Patients or Other Participants Thirty-six boys (mean age = 10.94 ± 1.34 years, height = 151.31 ± 12.17 cm, mass = 42.51 ± 10.32 kg) ranging in age from 8 to 12 years and involved in organized youth baseball. Main Outcome Measure(s) Diagnostic ultrasound was used to determine humeral retrotorsion and posterior-capsule thickness. Glenohumeral internal rotation and external rotation were measured using a handheld inclinometer. We used 2 × 2 mixed-model analyses of variance to compare the influence of limb dominance and age on the dependent variables of humeral retrotorsion, posterior-capsule thickness, internal rotation, and external rotation. Results The dominant shoulders of youth throwers exhibited less glenohumeral internal rotation but greater humeral retrotorsion, posterior-capsule thickness, and glenohumeral external rotation than the nondominant shoulders. Dominant internal rotation was greater in the 8- to 10-year-old group than in the 11- to 12-year-old group, and results trended toward a difference (F1,33 = 4.12, P = .05). Correlations existed between humeral retrotorsion and range of motion (P < .05). Conclusions The structural adaptations in the dominant shoulders of younger baseball players were similar to

  7. Ablation of Kv3.1 and Kv3.3 potassium channels disrupts thalamocortical oscillations in vitro and in vivo.

    PubMed

    Espinosa, Felipe; Torres-Vega, Miguel A; Marks, Gerald A; Joho, Rolf H

    2008-05-21

    The genes Kcnc1 and Kcnc3 encode the subunits for the fast-activating/fast-deactivating, voltage-gated potassium channels Kv3.1 and Kv3.3, which are expressed in several brain regions known to be involved in the regulation of the sleep-wake cycle. When these genes are genetically eliminated, Kv3.1/Kv3.3-deficient mice display severe sleep loss as a result of unstable slow-wave sleep. Within the thalamocortical circuitry, Kv3.1 and Kv3.3 subunits are highly expressed in the thalamic reticular nucleus (TRN), which is thought to act as a pacemaker at sleep onset and to be involved in slow oscillatory activity (spindle waves) during slow-wave sleep. We showed that in cortical electroencephalographic recordings of freely moving Kv3.1/Kv3.3-deficient mice, spectral power is reduced up to 70% at frequencies <15 Hz. In addition, the number of sleep spindles in vivo as well as rhythmic rebound firing of TRN neurons in vitro is diminished in mutant mice. Kv3.1/Kv3.3-deficient TRN neurons studied in vitro show approximately 60% increase in action potential duration and a reduction in high-frequency firing after depolarizing current injections and during rebound burst firing. The results support the hypothesis that altered electrophysiological properties of TRN neurons contribute to the reduced EEG power at slow frequencies in the thalamocortical network of Kv3-deficient mice.

  8. The Anomaly Power Transmission and Analysis at a 500kV GIS Substation

    NASA Astrophysics Data System (ADS)

    Qi, Geqing; Wu, Gang; Qi, Zhuang; Meng, Fanlong; Jin, Daxin; Zhang, Wei; Zhang, Nan; Wang, Lulu

    2017-07-01

    In view of the extension which steps up from 220kV to 500kV at the switching station, induced the flashover of insulation spacer in gas chamber from 500kV line side, the voltage fault of 500kV bus, the discharge of junction which between oil-gas casing of 500kV main transformer from 220kV bus side and GIS branch bus, due to improper installation. The paper analyzes connection diagram, graph of fault recorder and repair with disassembly point for point. It also suggests the recommendations for improvement, to avoid the appearance.

  9. The role of Kv3-type potassium channels in cerebellar physiology and behavior.

    PubMed

    Joho, Rolf H; Hurlock, Edward C

    2009-09-01

    Different subunits of the Kv3 subfamily of voltage-gated potassium (Kv) channels (Kv3.1-Kv3.4) are expressed in distinct neuronal subpopulations in the cerebellum. Behavioral phenotypes in Kv3-null mutant mice such as ataxia with prominent hypermetria and heightened alcohol sensitivity are characteristic of cerebellar dysfunction. Here, we review how the unique biophysical properties of Kv3-type potassium channels, fast activation and fast deactivation that enable cerebellar neurons to generate brief action potentials at high frequencies, affect firing patterns and influence cerebellum-mediated behavior.

  10. Comparison of a 250 kV single-stage accelerator mass spectrometer with a 5 MV tandem accelerator mass spectrometer--fitness for purpose in bioanalysis.

    PubMed

    Young, G C; Corless, S; Felgate, C C; Colthup, P V

    2008-12-01

    The introduction of 'compact' accelerator mass spectrometers into biomedical science, including use in drug metabolism and bioanalytical applications, is an exciting recent development. Comparisons are presented here between a more established and relatively large tandem accelerator which operates at up to 5 MV and a conventional laboratory-sized 250 kV single-stage accelerator mass spectrometer. Biological samples were enriched with low levels of radiocarbon, then converted into graphite prior to analysis on each of the two instruments. The data obtained showed the single-stage instrument to be capable of delivering comparable results, and thus able to provide similar study support, with that provided by the 5 MV instrument, without the significant overheads and complexities which are inherent to the operation of the larger instrument. We believe that the advent of these laboratory-sized accelerator mass spectrometry (AMS) instruments represents a real turning point in the potential for application of AMS by a wider user group.

  11. Kv3.4 subunits enhance the repolarizing efficiency of Kv3.1 channels in fast-spiking neurons.

    PubMed

    Baranauskas, Gytis; Tkatch, Tatiana; Nagata, Keiichi; Yeh, Jay Z; Surmeier, D James

    2003-03-01

    Neurons with the capacity to discharge at high rates--'fast-spiking' (FS) neurons--are critical participants in central motor and sensory circuits. It is widely accepted that K+ channels with Kv3.1 or Kv3.2 subunits underlie fast, delayed-rectifier (DR) currents that endow neurons with this FS ability. Expression of these subunits in heterologous systems, however, yields channels that open at more depolarized potentials than do native Kv3 family channels, suggesting that they differ. One possibility is that native channels incorporate a subunit that modifies gating. Molecular, electrophysiological and pharmacological studies reported here suggest that a splice variant of the Kv3.4 subunit coassembles with Kv3.1 subunits in rat brain FS neurons. Coassembly enhances the spike repolarizing efficiency of the channels, thereby reducing spike duration and enabling higher repetitive spike rates. These results suggest that manipulation of K3.4 subunit expression could be a useful means of controlling the dynamic range of FS neurons.

  12. Position-dependent attenuation by Kv1.6 of N-type inactivation of Kv1.4-containing channels.

    PubMed

    Al-Sabi, Ahmed; Kaza, Seshu; Le Berre, Marie; O'Hara, Liam; Bodeker, MacDara; Wang, Jiafu; Dolly, J Oliver

    2011-09-01

    Assembly of distinct α subunits of Kv1 (voltage-gated K(+) channels) into tetramers underlies the diversity of their outward currents in neurons. Kv1.4-containing channels normally exhibit N-type rapid inactivation, mediated through an NIB (N-terminal inactivation ball); this can be over-ridden if associated with a Kv1.6 α subunit, via its NIP (N-type inactivation prevention) domain. Herein, NIP function was shown to require positioning of Kv1.6 adjacent to the Kv1.4 subunit. Using a recently devised gene concatenation, heterotetrameric Kv1 channels were expressed as single-chain proteins on the plasmalemma of HEK (human embryonic kidney)-293 cells, so their constituents could be arranged in different positions. Placing the Kv1.4 and 1.6 genes together, followed by two copies of Kv1.2, yielded a K(+) current devoid of fast inactivation. Mutation of critical glutamates within the NIP endowed rapid inactivation. Moreover, separating Kv1.4 and 1.6 with a copy of Kv1.2 gave a fast-inactivating K(+) current with steady-state inactivation shifted to more negative potentials and exhibiting slower recovery, correlating with similar inactivation kinetics seen for Kv1.4-(1.2)(3). Alternatively, separating Kv1.4 and 1.6 with two copies of Kv1.2 yielded slow-inactivating currents, because in this concatamer Kv1.4 and 1.6 should be together. These findings also confirm that the gene concatenation can generate K(+) channels with α subunits in pre-determined positions.

  13. Behavioral motor dysfunction in Kv3-type potassium channel-deficient mice.

    PubMed

    Joho, R H; Street, C; Matsushita, S; Knöpfel, T

    2006-08-01

    The voltage-gated potassium channels Kv3.1 and Kv3.3 are expressed in several distinct neuronal subpopulations in brain areas known to be involved in motor control such as cortex, basal ganglia and cerebellum. Depending on the lack of Kv3.1 or Kv3.3 channel subunits, mutant mice show different Kv3-null allele-dependent behavioral alterations that include constitutive hyperactivity, sleep loss, impaired motor performance and, in the case of the Kv3.1/Kv3.3 double mutant, also severe ataxia, tremor and myoclonus (Espinosa et al. 2001, J Neurosci 21, 6657-6665, Genes, Brain Behav 3, 90-100). The lack of Kv3.1 channel subunits is mainly responsible for the constitutively increased locomotor activity and for sleep loss, whereas the absence of Kv3.3 subunits affects cerebellar function, in particular Purkinje cell discharges and olivocerebellar system properties (McMahon et al. 2004, Eur J Neurosci 19, 3317-3327). Here, we describe two sensitive and non-invasive tests to reliably quantify normal and abnormal motor functions, and we apply these tests to characterize motor dysfunction in Kv3-mutant mice. In contrast to wildtype and Kv3.1-single mutants, Kv3.3-single mutants and Kv3 mutants lacking three and four Kv3 alleles display Kv3-null allele-dependent gait alterations. Although the Kv3-null allele-dependent gait changes correlate with reduced motor performance, they appear to not affect the training-induced improvement of motor performance. These findings suggest that altered cerebellar physiology in the absence of Kv3.3 channels is responsible for impaired motor task execution but not motor task learning.

  14. Alternative splicing regulates kv3.1 polarized targeting to adjust maximal spiking frequency.

    PubMed

    Gu, Yuanzheng; Barry, Joshua; McDougel, Robert; Terman, David; Gu, Chen

    2012-01-13

    Synaptic inputs received at dendrites are converted into digital outputs encoded by action potentials generated at the axon initial segment in most neurons. Here, we report that alternative splicing regulates polarized targeting of Kv3.1 voltage-gated potassium (Kv) channels to adjust the input-output relationship. The spiking frequency of cultured hippocampal neurons correlated with the level of endogenous Kv3 channels. Expression of axonal Kv3.1b, the longer form of Kv3.1 splice variants, effectively converted slow-spiking young neurons to fast-spiking ones; this was not the case for Kv1.2 or Kv4.2 channel constructs. Despite having identical biophysical properties as Kv3.1b, dendritic Kv3.1a was significantly less effective at increasing the maximal firing frequency. This suggests a possible role of channel targeting in regulating spiking frequency. Mutagenesis studies suggest the electrostatic repulsion between the Kv3.1b N/C termini, created by its C-terminal splice domain, unmasks the Kv3.1b axonal targeting motif. Kv3.1b axonal targeting increased the maximal spiking frequency in response to prolonged depolarization. This finding was further supported by the results of local application of channel blockers and computer simulations. Taken together, our studies have demonstrated that alternative splicing controls neuronal firing rates by regulating the polarized targeting of Kv3.1 channels.

  15. Increased motor drive and sleep loss in mice lacking Kv3-type potassium channels.

    PubMed

    Espinosa, F; Marks, G; Heintz, N; Joho, R H

    2004-04-01

    The voltage-gated potassium channels Kv3.1 and Kv3.3 are widely expressed in the brain, including areas implicated in the control of motor activity and in areas thought to regulate arousal states. Although Kv3.1 and Kv3.3-single mutants show some physiological changes, previous studies revealed relatively subtle behavioral alterations suggesting that Kv3.1 and Kv3.3 channel subunits may be encoded by a pair of redundant genes. In agreement with this hypothesis, Kv3.1/Kv3.3-deficient mice display a 'strong' mutant phenotype that includes motor dysfunction (ataxia, myoclonus, tremor) and hyperactivity when exposed to a novel environment. In this paper we report that Kv3.1/Kv3.3-deficient mice are also constitutively hyperactive. Compared to wildtype mice, double mutants display 'restlessness' that is particularly prominent during the light period, when mice are normally at rest, characterized by more than a doubling of ambulatory and stereotypic activity, and accompanied by a 40% sleep reduction. When we reinvestigated both single mutants, we observed constitutive increases of ambulatory and stereotypic activity in conjunction with sleep loss in Kv3.1-single mutants but not in Kv3.3-single mutants. These findings indicate that the absence of Kv3.1-channel subunits is primarily responsible for the increased motor drive and the reduction in sleep time.

  16. Participation of KCNQ (Kv7) potassium channels in myogenic control of cerebral arterial diameter

    PubMed Central

    Zhong, Xi Zoë; Harhun, Maksym I; Olesen, Soren P; Ohya, Susumu; Moffatt, James D; Cole, William C; Greenwood, Iain A

    2010-01-01

    KCNQ gene expression was previously shown in various rodent blood vessels, where the products of KCNQ4 and KCNQ5, Kv7.4 and Kv7.5 potassium channel subunits, respectively, have an influence on vascular reactivity. The aim of this study was to determine if small cerebral resistance arteries of the rat express KCNQ genes and whether Kv7 channels participate in the regulation of myogenic control of diameter. Quantitative reverse transcription polymerase chain reaction (QPCR) was undertaken using RNA isolated from rat middle cerebral arteries (RMCAs) and immunocytochemistry was performed using Kv7 subunit-specific antibodies and freshly isolated RMCA myocytes. KCNQ4 message was more abundant than KCNQ5=KCNQ1, but KCNQ2 and KCNQ3 message levels were negligible. Kv7.1, Kv7.4 and Kv7.5 immunoreactivity was present at the sarcolemma of freshly isolated RMCA myocytes. Linopirdine (1 μm) partially depressed, whereas the Kv7 activator S-1 (3 and/or 20 μm) enhanced whole-cell Kv7.4 (in HEK 293 cells), as well as native RMCA myocyte Kv current amplitude. The effects of S-1 were voltage-dependent, with progressive loss of stimulation at potentials of >−15 mV. At the concentrations employed linopirdine and S-1 did not alter currents due to recombinant Kv1.2/Kv1.5 or Kv2.1/Kv9.3 channels (in HEK 293 cells) that are also expressed by RMCA myocytes. In contrast, another widely used Kv7 blocker, XE991 (10 μm), significantly attenuated native Kv current and also reduced Kv1.2/Kv1.5 and Kv2.1/Kv9.3 currents. Pressurized arterial myography was performed using RMCAs exposed to intravascular pressures of 10–100 mmHg. Linopirdine (1 μm) enhanced the myogenic response at ≥20 mmHg, whereas the activation of Kv7 channels with S-1 (20 μm) inhibited myogenic constriction at >20 mmHg and reversed the increased myogenic response produced by suppression of Kv2-containing channels with 30 nm stromatoxin (ScTx1). These data reveal a novel contribution of KCNQ gene products to the

  17. Isokinetic Scapular Muscle Performance in Overhead Athletes With and Without Impingement Symptoms.

    PubMed

    Cools, Ann M; Witvrouw, Erik E; Mahieu, Nele N; Danneels, Lieven A

    2005-06-01

    Context: Overhead activities such as throwing, tennis, or volleyball place athletes at considerable risk for overuse injuries. A relationship between scapulothoracic muscle imbalance and shoulder pain has been suggested.Objective: To compare the isokinetic muscle performance of the scapular muscles between overhead athletes with impingement symptoms and uninjured overhead athletes and to identify strength deficits in the patient population.Design: A repeated-measures analysis of variance with 1 within-subjects factor (side) and 1 between-subjects factor (group) was used to compare strength values and agonist:antagonist ratios across sides and across groups.Setting: University laboratory.Patients or Other Participants: Thirty overhead athletes with chronic shoulder impingement symptoms and 30 overhead athletes without a history of shoulder pain.Intervention(s): A linear protraction-retraction movement in the scapular plane at 2 velocities (12.2 cm/s and 36.6 cm/s).Main Outcome Measure(s): Isokinetic strength values and protraction:retraction ratios for both velocities.Results: Overhead athletes with impingement symptoms showed decreased force output:body weight at both velocities in the protractor muscles on the injured side compared with the uninjured side (-13.7% at slow velocity, -15.5% at high velocity) and compared with the control group at high velocity (-20.7%). On both sides, the patient group had significantly lower protraction:retraction ratios than the control group, measured at slow velocity (nondominant = -11%, dominant = -13.7%).Conclusions: Overhead athletes with impingement symptoms demonstrated strength deficits and muscular imbalance in the scapular muscles compared with uninjured athletes.

  18. The use of polymer horizontal vee arms for 120kV to 230kV conversion

    SciTech Connect

    Doubley, D. )

    1991-01-01

    This paper reports on Detroit Edison which is using the horizontal-vee configuration to convert 120 kV tower lines to 230 kV. This approach is an improvement over previous methods of existing line conversion. The design provides reduced construction costs; both in labor and material. It also provides improvement in line structure strength as well. The all polymer horizontal-vees as replacement for crossarms on existing towers make a substantial improvement in productivity. They are lighter, easier to handle, and less likely to break than their porcelain equivalents.

  19. Selective underexpression of Kv3.2 and Kv3.4 channels in the cortex of rats exposed to ethanol during early postnatal life.

    PubMed

    Tavian, Daniela; De Giorgio, Andrea; Granato, Alberto

    2011-08-01

    The expression of voltage-gated potassium channels belonging to the Kv3 family has been studied in the sensori-motor cortex of rats exposed to alcohol inhalation during the first postnatal week (P2-P6). The study was carried out using comparative RT-PCR. At P9, a significant reduction of the expression of Kv3.2 and Kv3.4 subunits occurred in alcohol-treated animals, as compared with controls. The expression of the Kv3.4a splicing variant, which is thought to be critically involved in the high-frequency firing of some cortical interneurons, was also correspondingly reduced. The downregulation of Kv3.2 and Kv3.4a subunits represented a long-lasting effect of alcohol exposure, since it was also observed in P24 animals. The expression of both Kv3.1 and Kv3.3 channels appeared to be not significantly affected by alcohol exposure. An increased susceptibility to apoptotic neuronal death after early postnatal exposure to ethanol was confirmed by the lower bcl-2/bax ratio observed in alcohol-treated animals. Although Kv3.4 subunits are thought to trigger apoptosis, the lack of upregulation in our model argues against their involvement in the mechanism leading to alcohol-induced apoptosis. The possible consequences of the selective downregulation of Kv3 subunits on the cortical function, as well as their relevance for the genesis of fetal alcohol effects, are discussed.

  20. Distribution of Kv3.3 potassium channel subunits in distinct neuronal populations of mouse brain.

    PubMed

    Chang, Su Ying; Zagha, Edward; Kwon, Elaine S; Ozaita, Andres; Bobik, Marketta; Martone, Maryann E; Ellisman, Mark H; Heintz, Nathaniel; Rudy, Bernardo

    2007-06-20

    Kv3.3 proteins are pore-forming subunits of voltage-dependent potassium channels, and mutations in the gene encoding for Kv3.3 have recently been linked to human disease, spinocerebellar ataxia 13, with cerebellar and extracerebellar symptoms. To understand better the functions of Kv3.3 subunits in brain, we developed highly specific antibodies to Kv3.3 and analyzed immunoreactivity throughout mouse brain. We found that Kv3.3 subunits are widely expressed, present in important forebrain structures but particularly prominent in brainstem and cerebellum. In forebrain and midbrain, Kv3.3 expression was often found colocalized with parvalbumin and other Kv3 subunits in inhibitory neurons. In brainstem, Kv3.3 was strongly expressed in auditory and other sensory nuclei. In cerebellar cortex, Kv3.3 expression was found in Purkinje and granule cells. Kv3.3 proteins were observed in axons, terminals, somas, and, unlike other Kv3 proteins, also in distal dendrites, although precise subcellular localization depended on cell type. For example, hippocampal dentate granule cells expressed Kv3.3 subunits specifically in their mossy fiber axons, whereas Purkinje cells of the cerebellar cortex strongly expressed Kv3.3 subunits in axons, somas, and proximal and distal, but not second- and third-order, dendrites. Expression in Purkinje cell dendrites was confirmed by immunoelectron microscopy. Kv3 channels have been demonstrated to rapidly repolarize action potentials and support high-frequency firing in various neuronal populations. In this study, we identified additional populations and subcellular compartments that are likely to sustain high-frequency firing because of the expression of Kv3.3 and other Kv3 subunits.

  1. Kv4.2 Knockout Mice Have Hippocampal-Dependent Learning and Memory Deficits

    ERIC Educational Resources Information Center

    Lugo, Joaquin N.; Brewster, Amy L.; Spencer, Corinne M.; Anderson, Anne E.

    2012-01-01

    Kv4.2 channels contribute to the transient, outward K[superscript +] current (A-type current) in hippocampal dendrites, and modulation of this current substantially alters dendritic excitability. Using Kv4.2 knockout (KO) mice, we examined the role of Kv4.2 in hippocampal-dependent learning and memory. We found that Kv4.2 KO mice showed a deficit…

  2. Kv4.2 Knockout Mice Have Hippocampal-Dependent Learning and Memory Deficits

    ERIC Educational Resources Information Center

    Lugo, Joaquin N.; Brewster, Amy L.; Spencer, Corinne M.; Anderson, Anne E.

    2012-01-01

    Kv4.2 channels contribute to the transient, outward K[superscript +] current (A-type current) in hippocampal dendrites, and modulation of this current substantially alters dendritic excitability. Using Kv4.2 knockout (KO) mice, we examined the role of Kv4.2 in hippocampal-dependent learning and memory. We found that Kv4.2 KO mice showed a deficit…

  3. Molecular and functional characterization of Kv7 K+ channel in murine gastrointestinal smooth muscles.

    PubMed

    Jepps, Thomas A; Greenwood, Iain A; Moffatt, James D; Sanders, Kenton M; Ohya, Susumu

    2009-07-01

    Members of the K(v)7 voltage-gated K(+) channel family are important determinants of cardiac and neuronal membrane excitability. Recently, we and others have shown that K(v)7 channels are also crucial regulators of smooth muscle activity. The aim of the present study was to assess the K(v)7 expression in different parts of the murine gastrointestinal (GI) tract and to assess their functional roles by use of pharmacological agents. Of KCNQ/K(v)7 members, both KCNQ4/K(v)7.4 and KCNQ5/K(v)7.5 genes and proteins were the most abundantly expressed K(v)7 channels in smooth muscles throughout the GI tract. Immunohistochemical staining also revealed that K(v)7.4 and K(v)7.5 but not K(v)7.1 were expressed in the circular muscle layer of the colon. In segments of distal colon circular muscle exhibiting spontaneous phasic contractions, the nonselective K(v)7 blockers XE991 and linopirdine increased the integral of tension. Increases in the integral of tension were also observed under conditions of neuronal blockade. Similar effects, although less marked, were observed in the proximal colon. As expected, the K(v)7.1-selective blocker chromanol 293B had no effect in either type of segment. These data show that K(v)7.x especially K(v)7.4 and K(v)7.5 are expressed in different regions of the murine gastrointestinal tract and blockers of K(v)7 channels augment inherent contractile activity. Drugs that selectively block K(v)7.4/7.5 might be promising therapeutics for the treatment of motility disorders such as constipation associated with irritable bowel syndrome.

  4. At 1200 Gallery, Block 63, looking west, showing 230 kv ...

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

    At 1200 Gallery, Block 63, looking west, showing 230 kv cables. These lines were installed in the 1960s and are no longer used. - Columbia Basin Project, Grand Coulee Dam & Franklin D. Roosevelt Lake, Across Columbia River, Southeast of Town of Grand Coulee, Grand Coulee, Grant County, WA

  5. Buffalo Flat Service 115-KV Transmission Project : Environmental Assessment.

    SciTech Connect

    United States. Bonneville Power Administration.

    1987-07-01

    The US Air Force has sited a radar transmitter at Buffalo Flat, near Christmas Valley, Oregon. This report discusses the environmental impacts of providing the electrical service for the installation. A 115 kV power transmission line will be built between LaPine and Buffalo Flat. Route alternatives as well as design alternatives are discussed. (ACR)

  6. ACUTE EFFECTS OF DIFFERENT SELF‐MASSAGE VOLUMES ON THE FMS™ OVERHEAD DEEP SQUAT PERFORMANCE

    PubMed Central

    Škarabot, Jakob; Vigotsky, Andrew D; Brown, Amanda Fernandes; Gomes, Thiago Matassoli; Novaes, Jefferson da Silva

    2017-01-01

    Background The Functional Movement Screen (FMS™) is a battery of tests designed to assess movement competency; the overhead deep squat test, specifically, has been shown to be an accurate predictor of overall FMS™ scores. Self‐massage (SM) is a ubiquitous warm‐up utilized to increase joint range of motion and, therefore, may be effective for improving performance of the overhead deep squat test. Purpose To examine how different doses (30, 60, 90, and 120 seconds) of SM of different areas of the body (plantar fascia, latissimus dorsi, and lateral thigh) affects the score obtained on an overhead deep squat test. Methods Twenty recreationally active females were recruited to be tested on four occasions: sessions one and two consisted of baseline testing, session three consisted of SM applied to the lateral thigh, and session four consisted of SM applied to the lateral torso and plantar fascia. Results In all SM conditions, at least 90 seconds was required for a change in deep squat score from baseline; therefore, it is concluded that SM the lateral torso, plantar fascia, and lateral thigh for 90 seconds or more are effective interventions for acutely improving overhead deep squat scores. Conclusion Self‐massage appears to be an effective modality for inducing acute improvements in the performance of the FMS™ overhead deep squat in all conditions tested. Level of evidence 2b PMID:28217420

  7. Overhead drilling: comparing three bases for aligning a drilling jig to vertical.

    PubMed

    Rempel, David; Star, Demetra; Barr, Alan; Janowitz, Ira

    2010-06-01

    Drilling overhead into concrete or metal ceilings is a strenuous task done by construction workers to hang ductwork, piping, and electrical equipment. The task is associated with upper body pain and musculoskeletal disorders. Previously, we described a field usability evaluation of a foot lever and inverted drill press intervention devices that were compared to the usual method for overhead drilling. Both interventions were rated as inferior to the usual method based on poor setup time and mobility. Three new interventions, which differed on the design used for aligning the drilling column to vertical, were compared to the usual method for overhead drilling by commercial construction workers (n=16). The usual method was associated with the highest levels of regional body fatigue and the poorest usability ratings when compared to the three interventions. Overall, the 'Collar Base' intervention design received the best usability ratings. Intervention designs developed for overhead drilling may reduce shoulder fatigue and prevent subsequent musculoskeletal disorders. These designs may also be useful for other overhead work such as lifting and supporting materials (e.g., piping, ducts) that are installed near the ceiling. Workplace health and safety interventions may require multiple rounds of field-testing prior to achieving acceptable usability ratings by the end users. (c) 2010 Elsevier Ltd. All rights reserved.

  8. Overhead drilling: Comparing three bases for aligning a drilling jig to vertical

    PubMed Central

    Rempel, David; Star, Demetra; Barr, Alan; Janowitz, Ira

    2010-01-01

    Problem Drilling overhead into concrete or metal ceilings is a strenuous task done by construction workers to hang ductwork, piping, and electrical equipment. The task is associated with upper body pain and musculoskeletal disorders. Previously, we described a field usability evaluation of a foot lever and inverted drill press intervention devices that were compared to the usual method for overhead drilling. Both interventions were rated as inferior to the usual method based on poor setup time and mobility. Method Three new interventions, which differed on the design used for aligning the drilling column to vertical, were compared to the usual method for overhead drilling by commercial construction workers (n=16). Results The usual method was associated with the highest levels of regional body fatigue and the poorest usability ratings when compared to the three interventions. Conclusion Overall, the ‘Collar Base’ intervention design received the best usability ratings. Impact on Industry Intervention designs developed for overhead drilling may reduce shoulder fatigue and prevent subsequent musculoskeletal disorders. These designs may also be useful for other overhead work such as lifting and supporting materials (e.g., piping, ducts) that are installed near the ceiling. Workplace health and safety interventions may require multiple rounds of field-testing prior to achieving acceptable usability ratings by the end users. PMID:20630276

  9. Two-Level Incremental Checkpoint Recovery Scheme for Reducing System Total Overheads

    PubMed Central

    Li, Huixian; Pang, Liaojun; Wang, Zhangquan

    2014-01-01

    Long-running applications are often subject to failures. Once failures occur, it will lead to unacceptable system overheads. The checkpoint technology is used to reduce the losses in the event of a failure. For the two-level checkpoint recovery scheme used in the long-running tasks, it is unavoidable for the system to periodically transfer huge memory context to a remote stable storage. Therefore, the overheads of setting checkpoints and the re-computing time become a critical issue which directly impacts the system total overheads. Motivated by these concerns, this paper presents a new model by introducing i-checkpoints into the existing two-level checkpoint recovery scheme to deal with the more probable failures with the smaller cost and the faster speed. The proposed scheme is independent of the specific failure distribution type and can be applied to different failure distribution types. We respectively make analyses between the two-level incremental and two-level checkpoint recovery schemes with the Weibull distribution and exponential distribution, both of which fit with the actual failure distribution best. The comparison results show that the total overheads of setting checkpoints, the total re-computing time and the system total overheads in the two-level incremental checkpoint recovery scheme are all significantly smaller than those in the two-level checkpoint recovery scheme. At last, limitations of our study are discussed, and at the same time, open questions and possible future work are given. PMID:25111048

  10. ACUTE EFFECTS OF DIFFERENT SELF-MASSAGE VOLUMES ON THE FMS™ OVERHEAD DEEP SQUAT PERFORMANCE.

    PubMed

    Monteiro, Estêvão Rios; Škarabot, Jakob; Vigotsky, Andrew D; Brown, Amanda Fernandes; Gomes, Thiago Matassoli; Novaes, Jefferson da Silva

    2017-02-01

    The Functional Movement Screen (FMS™) is a battery of tests designed to assess movement competency; the overhead deep squat test, specifically, has been shown to be an accurate predictor of overall FMS™ scores. Self-massage (SM) is a ubiquitous warm-up utilized to increase joint range of motion and, therefore, may be effective for improving performance of the overhead deep squat test. To examine how different doses (30, 60, 90, and 120 seconds) of SM of different areas of the body (plantar fascia, latissimus dorsi, and lateral thigh) affects the score obtained on an overhead deep squat test. Twenty recreationally active females were recruited to be tested on four occasions: sessions one and two consisted of baseline testing, session three consisted of SM applied to the lateral thigh, and session four consisted of SM applied to the lateral torso and plantar fascia. In all SM conditions, at least 90 seconds was required for a change in deep squat score from baseline; therefore, it is concluded that SM the lateral torso, plantar fascia, and lateral thigh for 90 seconds or more are effective interventions for acutely improving overhead deep squat scores. Self-massage appears to be an effective modality for inducing acute improvements in the performance of the FMS™ overhead deep squat in all conditions tested. 2b.

  11. Effects of overhead work configuration on muscle activity during a simulated drilling task.

    PubMed

    Maciukiewicz, Jacquelyn M; Cudlip, Alan C; Chopp-Hurley, Jaclyn N; Dickerson, Clark R

    2016-03-01

    Overhead work is a known catalyst for occupational shoulder injury. Industrial workers must often adopt awkward overhead postures and loading profiles to complete required tasks, potentially elevating injury risk. This research examined the combined influence of multiple overhead working parameters on upper extremity muscular demands for an industrial drilling application. Twenty-two right-handed males completed 24 unilateral and bilateral overhead work exertions stratified by direction (upward, forward), point of force application (15, 30 and 45 cm in front of the body), and whole-body posture (seated, standing). The dependency of electromyographic (EMG) activity on several factors was established. Significant two-way interactions existed between point of force application and direction (p < 0.0001) and direction and whole body posture (p < 0.0001). An average increase in muscular activity of 6.5% maximal voluntary contraction (MVC) occurred for the contralateral limb when the bilateral task was completed, compared to unilateral tasks, with less than a 1% MVC increase for the active limb. These findings assist evidence-based approaches to overhead tasks, specifically in the construction industry. A bilateral task configuration is recommended to reduce glenohumeral stability demands. As well, particularly for tasks with a far reach distance, design tasks to promote a forward directed exertion. The considerable inter-subject variability suggests that fixed heights are not ideal, and should be avoided, and where this is not possible reaches should be reduced.

  12. Kv1.1 null mice have enlarged hippocampus and ventral cortex

    PubMed Central

    Persson, Ann-Sophie; Westman, Eric; Wang, Fu-Hua; Khan, Firoj Hossain; Spenger, Christian; Lavebratt, Catharina

    2007-01-01

    Background Mutations in the Shaker-like voltage-gated potassium channel Kv1.1 are known to cause episodic ataxia type 1 and temporal lobe epilepsy. Mice that express a malfunctional, truncated Kv1.1 (BALB/cByJ-Kv1.1mceph/mceph) show a markedly enlarged hippocampus and ventral cortex in adulthood. Results To determine if mice lacking Kv1.1 also develop a brain enlargement similar to mceph/mceph, we transferred Kv1.1 null alleles to the BALB/cByJ background. Hippocampus and ventral cortex was then studied using in vivo 3D-magnetic resonance imaging and volume segmentation in adult Kv1.1 null mice, BALB/cByJ-Kv1.1mceph/mceph, BALB/cByJ-Kv1.1mceph/+, BALB.C3HeB -Kv1.1-/+ and wild type littermates. The Kv1.1 null brains had dramatically enlarged hippocampus and ventral cortex. Mice heterozygous for either the null allele or the mceph allele had normal-sized hippocampus and ventral cortex. Conclusion Total absence of Kv1.1 can induce excessive overgrowth of hippocampus and ventral cortex in mice with a BALB/cByJ background, while mice with one wild type Kv1.1 allele develop normal-sized brains. PMID:17250763

  13. Kv1 channels and neural processing in vestibular calyx afferents

    PubMed Central

    Meredith, Frances L.; Kirk, Matthew E.; Rennie, Katherine J.

    2015-01-01

    Potassium-selective ion channels are important for accurate transmission of signals from auditory and vestibular sensory end organs to their targets in the central nervous system. During different gravity conditions, astronauts experience altered input signals from the peripheral vestibular system resulting in sensorimotor dysfunction. Adaptation to altered sensory input occurs, but it is not explicitly known whether this involves synaptic modifications within the vestibular epithelia. Future investigations of such potential plasticity require a better understanding of the electrophysiological mechanisms underlying the known heterogeneity of afferent discharge under normal conditions. This study advances this understanding by examining the role of the Kv1 potassium channel family in mediating action potentials in specialized vestibular afferent calyx endings in the gerbil crista and utricle. Pharmacological agents selective for different sub-types of Kv1 channels were tested on membrane responses in whole cell recordings in the crista. Kv1 channels sensitive to α-dendrotoxin and dendrotoxin-K were found to prevail in the central regions, whereas K+ channels sensitive to margatoxin, which blocks Kv1.3 and 1.6 channels, were more prominent in peripheral regions. Margatoxin-sensitive currents showed voltage-dependent inactivation. Dendrotoxin-sensitive currents showed no inactivation and dampened excitability in calyces in central neuroepithelial regions. The differential distribution of Kv1 potassium channels in vestibular afferents supports their importance in accurately relaying gravitational and head movement signals through specialized lines to the central nervous system. Pharmacological modulation of specific groups of K+ channels could help alleviate vestibular dysfunction on earth and in space. PMID:26082693

  14. The contribution of Kv2.2-mediated currents decreases during the postnatal development of mouse dorsal root ganglion neurons.

    PubMed

    Regnier, Glenn; Bocksteins, Elke; Van de Vijver, Gerda; Snyders, Dirk J; van Bogaert, Pierre-Paul

    2016-03-01

    Delayed rectifier voltage-gated K(+)(Kv) channels play an important role in the regulation of the electrophysiological properties of neurons. In mouse dorsal root ganglion (DRG) neurons, a large fraction of the delayed rectifier current is carried by both homotetrameric Kv2 channels and heterotetrameric channels consisting of Kv2 and silent Kv (KvS) subunits (i.e., Kv5-Kv6 and Kv8-Kv9). However, little is known about the contribution of Kv2-mediated currents during the postnatal development ofDRGneurons. Here, we report that the Stromatoxin-1 (ScTx)-sensitive fraction of the total outward K(+)current (IK) from mouseDRGneurons gradually decreased (~13%,P < 0.05) during the first month of postnatal development. Because ScTx inhibits both Kv2.1- and Kv2.2-mediated currents, this gradual decrease may reflect a decrease in currents containing either subunit. However, the fraction of Kv2.1 antibody-sensitive current that only reflects the Kv2.1-mediated currents remained constant during that same period. These results suggested that the fractional contribution of Kv2.2-mediated currents relative toIKdecreased with postnatal age. SemiquantitativeRT-PCRanalysis indicated that this decrease can be attributed to developmental changes in Kv2.2 expression as themRNAlevels of the Kv2.2 subunit decreased gradually between 1 and 4 weeks of age. In addition, we observed age-dependent fluctuations in themRNAlevels of the Kv6.3, Kv8.1, Kv9.1, and Kv9.3 subunits. These results support an important role of both Kv2 and KvS subunits in the postnatal maturation ofDRGneurons.

  15. Survey of Magnetic Fields Near BPA 230-kV and 500-kV Transmission Lines.

    SciTech Connect

    Perrin, Nancy; Aggarwal, Rajinder Pal; Bracken, T. Daniel

    1991-05-20

    The purpose of this study was to characterize typical levels and variability of 60Hz magnetic fields at the centerline and edge of right-of-way of Bonneville Power Administration (BPA) 230-kV and 500-kV transmission lines. This was accomplished by taking magnetic field measurements at over 800 spans in Oregon and Washington. The spans were sampled using a stratified random sampling procedure with region (East vs. West), voltage (230-kV vs 500-kV), and circuit configuration as strata. There were five different circuit configuration groups for each region/voltage category requiring a total of 200 strata. Magnetic field measurements were taken at 13 locations under each span using an EMDEX-C as a survey meter. Additional information recorded for each span included conductor height (at 10 locations), right-of-way width, longitudinal and lateral slope, time of day, vegetation, terrain, weather conditions, temperature, wind speed, span length and presence of other lines in the corridor. 9 refs., 17 figs., 26 tabs.

  16. Lazy Checkpointing : Exploiting Temporal Locality in Failures to Mitigate Checkpointing Overheads on Extreme-Scale Systems

    SciTech Connect

    Tiwari, Devesh; Gupta, Saurabh; Vazhkudai, Sudharshan S

    2014-01-01

    Continuing increase in the computational power of supercomputers has enabled large-scale scientific applications in the areas of astrophysics, fusion, climate and combustion to run larger and longer-running simulations, facilitating deeper scientific insights. However, these long-running simulations are often interrupted by multiple system failures. Therefore, these applications rely on ``checkpointing'' as a resilience mechanism to store application state to permanent storage and recover from failures. \\\\ \\indent Unfortunately, checkpointing incurs excessive I/O overhead on supercomputers due to large size of checkpoints, resulting in a sub-optimal performance and resource utilization. In this paper, we devise novel mechanisms to show how checkpointing overhead can be mitigated significantly by exploiting the temporal characteristics of system failures. We provide new insights and detailed quantitative understanding of the checkpointing overheads and trade-offs on large-scale machines. Our prototype implementation shows the viability of our approach on extreme-scale machines.

  17. Communication overhead on the Intel Paragon, IBM SP2 and Meiko CS-2

    NASA Technical Reports Server (NTRS)

    Bokhari, Shahid H.

    1995-01-01

    Interprocessor communication overhead is a crucial measure of the power of parallel computing systems-its impact can severely limit the performance of parallel programs. This report presents measurements of communication overhead on three contemporary commercial multicomputer systems: the Intel Paragon, the IBM SP2 and the Meiko CS-2. In each case the time to communicate between processors is presented as a function of message length. The time for global synchronization and memory access is discussed. The performance of these machines in emulating hypercubes and executing random pairwise exchanges is also investigated. It is shown that the interprocessor communication time depends heavily on the specific communication pattern required. These observations contradict the commonly held belief that communication overhead on contemporary machines is independent of the placement of tasks on processors. The information presented in this report permits the evaluation of the efficiency of parallel algorithm implementations against standard baselines.

  18. Functional differences of a Kv2.1 channel and a Kv2.1/Kv1.2S4-chimera are confined to a concerted voltage shift of various gating parameters.

    PubMed

    Koopmann, R; Benndorf, K; Lorra, C; Pongs, O

    1997-01-01

    When expressed in Xenopus oocytes, the voltage-dependent K+ channels Kv1.2 and Kv2.1 have similar steady state parameters of activation but the kinetics of activation is significantly faster in the Kv1.2 channels. Activation results from intramolecular arrangements which start with the movement of the voltage sensor and end with the opening of the pore. The S4-segment and the H5-loop comprise at least part of the respective involved structural elements. The molecular mechanism of coupling between sensing of voltage and opening of the pore is less well understood. We have measured whole cell and single channel ionic currents in the rapidly activating Kv1.2 channel of the rat, the slowly activating Kv2.1 channel of the human, and in an S4-chimera Kv2.1/Kv1.2S4. With respect to the Kv2.1 channel, steady state activation and steady state C-type inactivation of the chimeric channel are shifted by more than 50 mV in the depolarizing direction. The property of rapid activation in Kv1.2 channels was not transferred to the Kv2.1 channels with the transplanted S4-region. Instead, the kinetics of activation, deactivation, and recovery from C-type inactivation as well as the voltage sensitivity of the 4-aminopyridine block are similar to the corresponding processes in Kv2.1 channels if they are related to the steady state activation and inactivation, respectively. The unitary current and the mean open time of single channel openings of the S4-chimeric channels resemble the respective values of Kv2.1 channels. It is concluded that the insertion of the S4-segment of Kv1.2 channels into Kv2.1 channels modifies the gating at the early steps of activation leaving all properties associated with the open state(s) of the Kv2.1 channels unaffected.

  19. Nitrate leaching beneath a containerized nursery crop receiving trickle or overhead irrigation.

    PubMed

    Colangelo, D J; Brand, M H

    2001-01-01

    Container production of nursery crops is intensive and a potential source of nitrogen release to the environment. This study was conducted to determine if trickle irrigation could be used by container nursery producers as an alternative to standard overhead irrigation to reduce nitrogen release into the environment. The effect of overhead irrigation and trickle irrigation on leachate nitrate N concentration, flow-weighted nitrate N concentration, leachate volume, and plant growth was investigated using containerized rhododendron (Rhododendron catawbiense Michx. 'Album') supplied with a controlled-release fertilizer and grown outdoors on top of soil-monolith lysimeters. Leachate was collected over two growing seasons and overwinter periods, and natural precipitation was allowed as a component of the system. Precipitation accounted for 69% of the water entering the overhead-irrigated system and 80% of the water entering the trickle-irrigated system. Leachate from fertilized plants exceeded the USEPA limit of 10 mg L(-1) at several times and reached a maximum of 26 mg L(-1) with trickle irrigation. Average annual loss of nitrate N in leachate for fertilized treatments was 51.8 and 60.5 kg ha(-1) for the overhead and trickle treatments, respectively. Average annual flow-weighted concentration of nitrate N in leachate of fertilized plants was 7.2 mg L(-1) for overhead irrigation and 12.7 mg L(-1) for trickle irrigation. Trickle irrigation did not reduce the amount of nitrate N leached from nursery containers when compared with overhead irrigation because precipitation nullified the potential benefits of reduced leaching fractions and irrigation inputs provided under trickle irrigation.

  20. Vertical jumping height and horizontal overhead throwing velocity in young male athletes.

    PubMed

    Viitasalo, J T; Rahkila, P; Osterback, L; Alén, M

    1992-10-01

    The purpose of this study was to examine the effects of calendar and skeletal age, anthropometric dimensions, training history and their interactions on vertical jumping height and horizontal overhead throwing velocity in a cross-section of 318 young male athletes (age range 9-16 years) participating in cross-country skiing (n = 70), basketball (n = 40), apparatus gymnastics (n = 19), ice hockey (n = 50), track and field (n = 89) and wrestling (n = 50). Vertical jumping height was measured with four different loads held on the shoulders and then interpolated for loads representing 0 and 40% body mass. Horizontal overhead throwing velocity using both hands was determined for seven balls of different weights and then interpolated for weights representing 1 and 5% body mass. Both vertical jumping height and overhead throwing velocity were found to increase (P < 0.01) from the skeletally youngest to the oldest cohort when the effects of body height and mass were controlled. The inter-event comparisons did not reveal statistically significant differences in respect of vertical jumping height. Also in the overhead throwing tests, the inter-event differences were small, although the analysis of variance revealed statistically significant (P < 0.001) differences for the skeletal age cohorts of 13 and 14 years. While the quantity of training had no effect on vertical jumping height, it explained the results in the overhead throwing test. The effects of training on vertical jumping and horizontal overhead throwing among adolescent athletes were considered to be small, while maturational processes and anthropometric development followed by increase in calendar age were deemed to be of greater importance.

  1. Complexes of Peptide Blockers with Kv1.6 Pore Domain: Molecular Modeling and Studies with KcsA-Kv1.6 Channel.

    PubMed

    Nekrasova, O V; Volyntseva, A D; Kudryashova, K S; Novoseletsky, V N; Lyapina, E A; Illarionova, A V; Yakimov, S A; Korolkova, Yu V; Shaitan, K V; Kirpichnikov, M P; Feofanov, A V

    2016-09-17

    Potassium voltage-gated Kv1.6 channel, which is distributed primarily in neurons of central and peripheral nervous systems, is of significant physiological importance. To date, several high-affinity Kv1.6-channel blockers are known, but the lack of selective ones among them hampers the studies of tissue localization and functioning of Kv1.6 channels. Here we present an approach to advanced understanding of interactions of peptide toxin blockers with a Kv1.6 pore. It combines molecular modeling studies and an application of a new bioengineering system based on a KcsA-Kv1.6 hybrid channel for the quantitative fluorescent analysis of blocker-channel interactions. Using this system we demonstrate that peptide toxins agitoxin 2, kaliotoxin1 and OSK1 have similar high affinity to the extracellular vestibule of the K(+)-conducting pore of Kv1.6, hetlaxin is a low-affinity ligand, whereas margatoxin and scyllatoxin do not bind to Kv1.6 pore. Binding of toxins to Kv1.6 pore has considerable inverse dependence on the ionic strength. Model structures of KcsA-Kv1.6 and Kv1.6 complexes with agitoxin 2, kaliotoxin 1 and OSK1 were obtained using homology modeling and molecular dynamics simulation. Interaction interfaces, which are formed by 15-19 toxin residues and 10 channel residues, are described and compared. Specific sites of Kv1.6 pore recognition are identified for targeting of peptide blockers. Analysis of interactions between agitoxin 2 derivatives with point mutations (S7K, S11G, L19S, R31G) and KcsA-Kv1.6 confirms reliability of the calculated complex structure.

  2. Overhead Allocation and Marginal Cost in U.S. and Brazilian Defense Contracting

    DTIC Science & Technology

    1993-12-01

    r - A𔃽 ZAC• 3 / 0U S , "shot-une and-long-ru’nd ahr- u verages and marginalcoture.I Figure 6, we can see that LRAC and LRMC are long-run average and...NAVAL POSTGRADUATE SCHOOL Monterey, California DTIC At)"’ S EL~ECTE A~r.~AAPR 1 2 1994U THESIS OVERHEAD ALLOCATION AND MARGINAL COST IN U.S. AND...Master~ s Thesis 4. TITLE AND SUBTITLE OVERHEAD ALLOCATION AND S . FUNDING NUMBERS M’ARG[NAL COST IN U.S. AND BRAZILIAN DEFENSE CONTRACTING 6. AUTHOR

  3. The transient outward current in mice lacking the potassium channel gene Kv1.4

    PubMed Central

    London, Barry; Wang, Dao W; Hill, Joseph A; Bennett, Paul B

    1998-01-01

    The transient outward current (Ito) plays a prominent role in the repolarization phase of the cardiac action potential. Several K+ channel genes, including Kv1.4, are expressed in the heart, produce rapidly inactivating currents when heterologously expressed, and may be the molecular basis of Ito.We engineered mice homozygous for a targeted disruption of the K+ channel gene Kv1.4 and compared Ito in wild-type (Kv1.4+/+), heterozygous (Kv1.4+/-) and homozygous ‘knockout’ (Kv1.4−/−) mice. Kv1.4 RNA was truncated in Kv1.4−/− mice and protein expression was absent.Adult myocytes isolated from Kv1.4+/+, Kv1.4+/− and Kv1.4−/− mice had large rapidly inactivating outward currents. The peak current densities at 60 mV (normalized by cellular capacitance, in pA pF−1; means ± s.e.m.) were 53.8 ± 5.3, 45.3 ± 2.2 and 44.4 ± 2.8 in cells from Kv1.4+/+, Kv1.4+/− and Kv1.4−/− mice, respectively (P < 0.02 for Kv1.4+/+ vs. Kv1.4−/−). The steady-state values (800 ms after the voltage clamp step) were 30.9 ± 2.9, 26.9 ± 3.8 and 23.5 ± 2.2, respectively (P < 0.02 for Kv1.4+/+ vs. Kv1.4−/−). The inactivating portion of the current was unchanged in the targeted mice.The voltage dependence and time course of inactivation were not changed by targeted disruption of Kv1.4. The mean best-fitting V½ (membrane potential at 50 % inactivation) values for myocytes from Kv1.4 +/+, Kv1.4+/− and Kv1.4−/− mice were -53.5 ± 3.7, -51.1 ± 2.6 and -54.2 ± 2.4 mV, respectively. The slope factors (k) were -10.1 ± 1.4, -8.8 ± 1.4 and -9.5 ± 1.2 mV, respectively. The fast time constants for development of inactivation at -30 mV were 27.8 ± 2.2, 26.2 ± 5.1 and 19.6 ± 2.1 ms in Kv1.4+/+, Kv1.4+/− and Kv1.4−/− myocytes, respectively. At +30 mV, they were 35.5 ± 2.6, 30.0 ± 2.1 and 28.7 ± 1.6 ms, respectively. The time constants for the rapid phase of recovery from inactivation at -80 mV were 32.5 ± 8.2, 23.3 ± 1.8 and 39.0 ± 3.7 ms, respectively

  4. Differential expression of Kv3.1b and Kv3.2 potassium channel subunits in interneurons of the basolateral amygdala.

    PubMed

    McDonald, A J; Mascagni, F

    2006-01-01

    The expression of Kv3.1 and Kv3.2 voltage-gated potassium channel subunits appears to be critical for high-frequency firing of many neuronal populations. In the cortex these subunits are mainly associated with fast-firing GABAergic interneurons containing parvalbumin or somatostatin. Since the basolateral nuclear complex of the amygdala contains similar interneurons, it is of interest to determine if these potassium channel subunits are expressed in these same interneuronal subpopulations. To investigate this issue, peroxidase and dual-labeling fluorescence immunohistochemistry combined with confocal laser scanning microscopy was used to determine which interneuronal subpopulations in the basolateral nuclear complex of the rat amygdala express Kv3.1b and Kv3.2 subunits. Antibodies to parvalbumin, somatostatin, calretinin, and cholecystokinin were used to label separate subsets of basolateral amygdalar interneurons. Examination of immunoperoxidase preparations suggested that the expression of both channels was restricted to nonpyramidal interneurons in the basolateral amygdala. Somata and proximal dendrites were intensely-stained, and axon terminals arising from presumptive basket cells and chandelier cells were lightly stained. Immunofluorescence observations revealed that parvalbumin+ neurons were the main interneuronal subpopulation expressing the Kv3.1b potassium channel subunit in the basolateral amygdala. More than 92-96% of parvalbumin+ neurons were Kv3.1b+, depending on the nucleus. These parvalbumin+/Kv3.1b+ double-labeled cells constituted 90-99% of all Kv3.1b+ neurons. Parvalbumin+ neurons were also the main interneuronal subpopulation expressing the Kv3.2 potassium channel subunit. More than 67-78% of parvalbumin+ neurons were Kv3.2+, depending on the nucleus. However, these parvalbumin+/Kv3.2+ double-labeled cells constituted only 71-81% of all Kv3.2+ neurons. Most of the remaining neurons with significant levels of the Kv3.2 subunit were somatostatin

  5. Kv3.1b is a novel component of CNS nodes.

    PubMed

    Devaux, Jérôme; Alcaraz, Gisèle; Grinspan, Judith; Bennett, Vann; Joho, Rolf; Crest, Marcel; Scherer, Steven S

    2003-06-01

    We herein demonstrate that Kv3.1b subunits are present at nodes of Ranvier in the CNS of both rats and mice. Kv3.1b colocalizes with voltage-gated Na+ channels in a subset of nodes in the spinal cord, particularly those of large myelinated axons. Kv3.1b is abundantly expressed in the gray matter of the spinal cord, but does not colocalize with Na+ channels in initial segments. In the PNS, few nodes are Kv3.1b-positive. During the development of the CNS, Kv3.1b clustering at nodes occurs later than that of Na+ channels, but precedes the juxtaparanodal clustering of Kv1.2. Moreover, in myelin-deficient rats, which have severe CNS dysmyelination, node-like clusters of Kv3.1b and Na+ channels are observed even in regions devoid of oligodendrocytes. Ankyrin G coimmunoprecipitates Kv3.1b in vivo, indicating that these two proteins may interact in the CNS at nodes. 4-Aminopyridine, a K+ channel blocker, broadened the compound action potential recorded from adult rat optic nerve and spinal cord, but not from the sciatic nerve. These effects were also observed in Kv3.1-deficient mice. In conclusion, Kv3.1b is the first K+ channel subunit to be identified in CNS nodes; but Kv3.1b does not account for the effects of 4-aminopyridine on central myelinated tracts.

  6. Src regulates membrane trafficking of the Kv3.1b channel.

    PubMed

    Bae, Seong Han; Kim, Dong Hyun; Shin, Seok Kyo; Choi, Jin Sung; Park, Kang-Sik

    2014-01-03

    The Kv3.1 channel plays a crucial role in regulating the high-frequency firing properties of neurons. Here, we determined whether Src regulates the subcellular distributions of the Kv3.1b channel. Co-expression of active Src induced a dramatic redistribution of Kv3.1b to the endoplasmic reticulum. Furthermore, co-expression of the Kv3.1b channel with active Src induced a remarkable decrease in the pool of Kv3.1b at the cell surface. Moreover, the co-expression of active Src results in a significant decrease in the peak current densities of the Kv3.1b channel, and a substantial alteration in the voltage dependence of its steady-state inactivation. Taken together, these results indicate that Src kinase may play an important role in regulating membrane trafficking of Kv3.1b channels.

  7. β Subunits Functionally Differentiate Human Kv4.3 Potassium Channel Splice Variants

    PubMed Central

    Abbott, Geoffrey W.

    2017-01-01

    The human ventricular cardiomyocyte transient outward K+ current (Ito) mediates the initial phase of myocyte repolarization and its disruption is implicated in Brugada Syndrome and heart failure (HF). Human cardiac Ito is generated primarily by two Kv4.3 splice variants (Kv4.3L and Kv4.3S, diverging only by a C-terminal, S6-proximal, 19-residue stretch unique to Kv4.3L), which are differentially remodeled in HF, but considered functionally alike at baseline. Kv4.3 is regulated in human heart by β subunits including KChIP2b and KCNEs, but their effects were previously assumed to be Kv4.3 isoform-independent. Here, this assumption was tested experimentally using two-electrode voltage-clamp analysis of human subunits co-expressed in Xenopus laevis oocytes. Unexpectedly, Kv4.3L-KChIP2b channels exhibited up to 8-fold lower current augmentation, 40% slower inactivation, and 5 mV-shifted steady-state inactivation compared to Kv4.3S-KChIP2b. A synthetic peptide mimicking the 19-residue stretch diminished these differences, reinforcing the importance of this segment in mediating Kv4.3 regulation by KChIP2b. KCNE subunits induced further functional divergence, including a 7-fold increase in Kv4.3S-KCNE4-KChIP2b current compared to Kv4.3L-KCNE4-KChIP2b. The discovery of β-subunit-dependent functional divergence in human Kv4.3 splice variants suggests a C-terminal signaling hub is crucial to governing β-subunit effects upon Kv4.3, and demonstrates the potential significance of differential Kv4.3 gene-splicing and β subunit expression in myocyte physiology and pathobiology. PMID:28228734

  8. Regulation of Kv2.1 K+ conductance by cell surface channel density

    PubMed Central

    Fox, Philip D.; Loftus, Rob J.; Tamkun, Michael M.

    2013-01-01

    The Kv2.1 voltage-gated K+ channel is found both freely diffusing over the plasma membrane and concentrated in micron-sized clusters localized to the soma, proximal dendrites and axon initial segment of hippocampal neurons. In transfected HEK cells, Kv2.1 channels within cluster microdomains are non-conducting. Using TIRF microscopy the number of GFP-tagged Kv2.1 channels on the HEK cell surface was compared to K+ channel conductance measured by whole-cell voltage-clamp of the same cell. This approach indicated that as channel density increases non-clustered channels cease conducting. At the highest density observed, only 4% of all channels were conducting. Mutant Kv2.1 channels that fail to cluster also possessed the non-conducting state with 17% conducting K+ at higher surface densities. The non-conducting state was specific to Kv2.1 as Kv1.4 was always conducting regardless of the cell-surface expression level. Anti-Kv2.1 immuno-fluorescence intensity, standardized to Kv2.1 surface density in transfected HEK cells, was used to determine the expression levels of endogenous Kv2.1 in cultured rat hippocampal neurons. Endogenous Kv2.1 levels were compared to the number of conducting channels determined by whole-cell voltage clamp. Only 13 and 27% of the endogenous Kv2.1 was conducting in neurons cultured for 14 and 20 days, respectively. Together these data indicate that the non-conducting state depends primarily on surface density as opposed to cluster location and that this non-conducting state also exists for native Kv2.1 found in cultured hippocampal neurons. This excess of Kv2.1 protein relative to K+ conductance further supports a non-conducting role for Kv2.1 in excitable tissues. PMID:23325261

  9. Neuronal activity and TrkB ligands influence Kv3.1b and Kv3.2 expression in developing cortical interneurons.

    PubMed

    Grabert, J; Wahle, P

    2008-10-15

    Among the GABAergic neocortical interneurons, fast-spiking (FS) basket and chandelier cells are essential mediators for feed-forward inhibition, network synchrony and oscillations. The FS properties are in part mediated by the voltage-gated potassium channels Kv3.1b/3.2 which allow the fast repolarization of the membrane necessary for firing non-adapting action potentials at high frequencies. It has been recently reported that the FS phenotype fails to mature in BDNF knockout mice suggesting a role for neurotrophins. We now describe the role of neuronal activity and neurotrophins for Kv3.1b/3.2 expression using organotypic cultures of rat visual cortex as model system. Chronic activity deprivation from 2 days in vitro (DIV) prevented the postnatal developmental increase of Kv3.2, but not Kv3.1b mRNA expression. However, chronic activity deprivation failed to alter Kv3.1b and marginally delayed Kv3.2 protein expression. Activity deprivation by glutamate receptor blockade from 10 to 20 DIV reduced both mRNAs, whereas deprivation with tetrodotoxin (TTX) reduced both mRNAs and the Kv3.2 protein. Thalamic and cortical afferents in cocultures failed to alter the expression. BDNF and NT4 supplemented from 2 DIV onwards increased the expression of Kv3.1b, but not Kv3.2 mRNA in young cultures. Only NT4 increased the expression of both mRNAs later in development. Kv3 protein levels were not changed by exogenous tropomyosin-related kinase B (TrkB) ligands, but the levels decreased upon inhibiting the MAPK signaling suggesting a role for endogenous factors and in particular MEK2 signaling for translation. The results show that Kv3.1b/3.2 expression is differentially controlled by neuronal activity and neurotrophic factors.

  10. Feasibility of Dose Reduction Using Novel Denoising Techniques for Low kV (80 kV) CT Enterography: Optimization and Validation

    PubMed Central

    Guimarães, Luís S; Fletcher, Joel G; Yu, Lifeng; Huprich, James E; Fidler, Jeff L.; Manduca, Armando; Ramirez-Giraldo, Juan Carlos; Holmes, David R.; McCollough, Cynthia H

    2010-01-01

    Rational and Objectives To optimize and validate projection space denoising (PSDN) strategies for application to 80 kV computed tomography (CT) data to achieve 50% dose reduction. Materials and Methods This retrospective HIPAA-compliant study had IRB approval. We utilized 80 kV image data (mean CTDIvol 7.9 mGy) obtained from dual-source dual-energy CTE exams in 42 patients. For each exam, nine 80 kV image datasets were reconstructed using PSDN (3 levels of intensity) ± image-based denoising and compared to commercial reconstruction kernels. For optimization, qualitative analysis selected optimal denoising strategies, with quantitative analysis measuring image contrast, noise and sharpness (FWHM bowel wall thickness, maximum CT number gradient). For validation, two radiologists examined image quality, comparing low-dose 80 kV optimally denoised images to full dose mixed kV images. Results PSDN algorithms generated the best 80 kV image quality (41/42 patients), while the commercial kernels produced the worst (39/42, p < 0.001). Overall 80 kV PSDN approaches resulted in higher contrast (mean 332 HU vs. 290 HU), slightly less noise (mean 20 HU vs. 26 HU), but slightly decreased images sharpness (relative bowel wall thickness, 1.069 vs. 1.000) compared to full-dose mixed kV images. Mean image quality scores for full-dose CTE images was 4.9 compared to 4.5 for optimally-denoised half-dose 80 kV CTE images, and 3.1 for non-denoised 80 kV CTE images (p<0.001). Conclusion Optimized denoising strategies improve the quality of 80 kV CT enterography images such that CT data obtained at 50% of routine dose levels approaches the image quality of full-dose exams. PMID:20832023

  11. Nervous system KV7 disorders: breakdown of a subthreshold brake.

    PubMed

    Maljevic, Snezana; Wuttke, Thomas V; Lerche, Holger

    2008-04-01

    Voltage-gated K+channels of the K(V)7 (KCNQ) family have been identified in the last 10-15 years by discovering the causative genes for three autosomal dominant diseases: cardiac arrhythmia (long QT syndrome) with or without congenital deafness (KCNQ1), a neonatal epilepsy (KCNQ2 and KCNQ3) and progressive deafness alone (KCNQ4). A fifth member of this gene family (KCNQ5) is not affected in a disease so far. Four genes (KCNQ2-5) are expressed in the nervous system. This review is focused on recent findings on the neuronal K(V)7 channelopathies, in particular on benign familial neonatal seizures (BFNS) and peripheral nerve hyperexcitability (PNH, neuromyotonia, myokymia) caused by KCNQ2 mutations. The phenotypic spectrum associated with KCNQ2 mutations is probably broader than initially thought, as patients with severe epilepsies and developmental delay, or with Rolando epilepsy have been described. With regard to the underlying molecular pathophysiology, it has been shown that mutations with very subtle changes restricted to subthreshold voltages can cause BFNS thereby proving in a human disease model that this is the relevant voltage range for these channels to modulate neuronal firing. The two mutations associated with PNH induce much more severe channel dysfunction with a dominant negative effect on wild type (WT) channels. Finally, K(V)7 channels present interesting targets for new therapeutic approaches to diseases caused by neuronal hyperexcitability, such as epilepsy, neuropathic pain, and migraine. The molecular mechanism of K(V)7 activation by retigabine, which is in phase III clinical testing to treat pharmacoresistant focal epilepsies, has been recently elucidated as a stabilization of the open conformation by binding to the pore region.

  12. Demonstrating Heat Changes on the Overhead Projector with a Projecting Thermometer.

    ERIC Educational Resources Information Center

    Hur, Chinhyu; Solomon, Sally; Wetzel, Christy

    1998-01-01

    Heat changes in a lecture setting can be safely shown on an overhead projector using a simple and inexpensive apparatus. Heat evolution can be observed on a projector with adapted digital thermometers or by illuminating the red fluid in nonmercury thermometers. Describes a setup for doing this as well as a collection of demonstrations involving…

  13. Marangoni Flowers and the Evil Eye: Overhead Presentations of Marangoni Flow

    ERIC Educational Resources Information Center

    Mundell, Donald W.

    2009-01-01

    Intermolecular forces and surface tension gradients in solutions lead to remarkable flows, known as Marangoni flows, where liquid flows from a region of low surface tension towards higher surface tension. Details of these flows, not visible to the naked eye, are made visible on an overhead projector owing to variation in the index of refraction.…

  14. 75 FR 75 - Special Conditions: Boeing Model 787-8 Airplane; Overhead Crew Rest Compartment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-04

    ... jet transport airplane with a two-aisle cabin. The maximum takeoff weight will be 476,000 pounds, with... Staff, Transport Airplane Directorate, Aircraft Certification Service, 1601 Lind Avenue, SW., Renton...-8 airplanes with an overhead crew rest (OCR) compartment installed above the main passenger...

  15. How To Set Up Your Own Small Business. Volumes I-II and Overhead Transparencies.

    ERIC Educational Resources Information Center

    Fallek, Max

    This two-volume textbook and collection of overhead transparency masters is intended for use in a course in setting up a small business. The following topics are covered in the first volume: getting off to a good start, doing market research, forecasting sales, financing a small business, understanding the different legal needs of different types…

  16. 48 CFR 3452.216-71 - Negotiated overhead rates-fixed.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 7 2010-10-01 2010-10-01 false Negotiated overhead rates-fixed. 3452.216-71 Section 3452.216-71 Federal Acquisition Regulations System DEPARTMENT OF EDUCATION ACQUISITION REGULATION CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Texts of Provisions...

  17. Apparatus for positioning modular components on a vertical or overhead surface

    NASA Technical Reports Server (NTRS)

    Haynig, C. C.; Messineo, S. V. (Inventor)

    1976-01-01

    An apparatus is disclosed for holding a plurality of modular components against a surface. A fixture prepositions the components and a vacuum develops a uniform pressure which presses and holds the fixture and objects against a surface. The surface may be curved, vertical, or overhead and since local load concentrations are avoided, fragile ceramic tiles may be installed using the apparatus.

  18. Early field performance of Acacia koa seedlings grown under subirrigation and overhead irrigation

    Treesearch

    Anthony S. Davis; Jeremiah R. Pinto; Douglass F. Jacobs

    2011-01-01

    Koa (Acacia koa A. Gray [Fabaceae]) seedlings were grown with subirrigation and overhead irrigation systems in an effort to characterize post-nursery field performance. One year following outplanting, we found no differences in seedling height or survival, but root-collar diameter was significantly larger for subirrigated seedlings. This indicates that koa seedlings,...

  19. Marangoni Flowers and the Evil Eye: Overhead Presentations of Marangoni Flow

    ERIC Educational Resources Information Center

    Mundell, Donald W.

    2009-01-01

    Intermolecular forces and surface tension gradients in solutions lead to remarkable flows, known as Marangoni flows, where liquid flows from a region of low surface tension towards higher surface tension. Details of these flows, not visible to the naked eye, are made visible on an overhead projector owing to variation in the index of refraction.…

  20. Redesigning the rural health center: high tech, high touch, and low overhead.

    PubMed

    Crane, Steven

    2011-01-01

    To attract new physicians to rural primary care, new models of care are needed that are more effective, more sustainable, and replicable in smaller communities. This commentary provides a brief description of preliminary findings associated with a radically redesigned, low-overhead patient-centered medical-home practice model in North Carolina.

  1. Self-actuating grapple automatically engages and releases loads from overhead cranes

    NASA Technical Reports Server (NTRS)

    Froehlich, J. A.; Karastas, G. A.

    1966-01-01

    Two-piece grapple mechanism consisting of a lift knob secured to the load and a grapple member connected to the crane or lift automatically disengages the load from the overhead lifting device when the load contacts the ground. The key feature is the sliding collar under the lift knob which enables the grapple latch to be stripped off over the lift knob.

  2. 45. MACHINE SHOP NORTH/NORTHEAST INCLUDING OVERHEAD LINE SHAFTING. MOSTLY BELT ...

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

    45. MACHINE SHOP NORTH/NORTHEAST INCLUDING OVERHEAD LINE SHAFTING. MOSTLY BELT DRIVEN WITH ONE ROPE DRIVEN LATHE IN MIDDLE GROUND. POWER COMES FROM KNIGHT TURBINE ON FAR WALL SHOWN IN K-77, 78 (42') - Knight Foundry, 13 Eureka Street, Sutter Creek, Amador County, CA

  3. 45. DETAIL OF OVERHEAD SERVICE CRANE (5TON CRANE MANUFACTURED BY ...

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

    45. DETAIL OF OVERHEAD SERVICE CRANE (5-TON CRANE MANUFACTURED BY ARMINGTON CARRIAGE; 3-TON HOIST MANUFACTURED BY WRIGHT HOIST COMPANY) IN VALVEHOUSE FOR NEEDLE VALVE OUTLET WORKS ON GALLERY 2. VIEW TO EAST. - Owyhee Dam, Across Owyhee River, Nyssa, Malheur County, OR

  4. Four limb amputations due to electrical burn caused by TV antenna contact with overhead electric cables.

    PubMed

    Celiköz, B; Sengezer, M; Selmanpakoğlu, N

    1997-02-01

    A 22-year-old man who sustained four limb amputations due to an electrical burn caused by contact of a TV receiver antenna with overhead electric cables is presented. The indications for limb amputation and the necessary preventive measures for such injuries are discussed.

  5. Using the Overhead Projector as a Light Source for Physics Demonstrations

    ERIC Educational Resources Information Center

    Mak, Se-Yuen

    2006-01-01

    This article illustrates how the overhead projector can be used as a light source in some peculiar ways for physics demonstrations. Five examples are included: (1) Study of chromatic aberration; (2) Making giant Newton's rings; (3) Comparison of the rate of heat absorption by different surfaces; (4) Demonstration of greenhouse effect; and (5)…

  6. Protection of the pediatric surgeon from heat stress caused by the overhead radiant heater during surgery.

    PubMed

    Bar-Maor, J A; Shitzer, A

    1988-09-01

    To protect the pediatric surgeon from heat stress while operating on premature infants under an overhead radiant heater, we propose covering the surgeon's head with an ordinary straw hat wrapped with heavy-duty kitchen aluminum foil. The temperature under such a straw hat is approximately 37 degrees C, versus 52 degrees C under a surgical cotton cap.

  7. Design and Application of Cables and Overhead Lines in Wind Power Plants

    SciTech Connect

    Behnke, M. R.; Bellei, T.A.; Bloethe, W.G.; Bradt, M.; Brooks, C.; Camm, E H; Dilling, W.; Goltz, B.; Hermanson, J.; Li, J.; Loy, P.; McLean, K.; Niemira, J.; Nuckles, K.; Patino, J.; Reza, M; Richardson, B.; Samaan, N.; Schoene, Jens; Smith, Travis M; Snyder, Isabelle B; Starke, Michael R; Tesch, M.; Walling, R.; Zahalka, G.

    2010-01-01

    This paper presents a summary of the most impor- tant considerations for wind power plant collection system un- derground and overhead cable designs. Various considerations, including conductor selection, soil thermal properties, installa- tion methods, splicing, concentric grounding, and NESC/NEC requirements are discussed.

  8. Demonstrating Biological Principles Efficiently and Effectively: The Overhead Is More than Just a Lighted Chalkboard

    ERIC Educational Resources Information Center

    Barden-Gabbei, Laura M.

    2006-01-01

    The overhead projector is an excellent tool for teachers at both the high school and college level. Teachers often use it to display class notes as they monitor students' actions and reactions to the concepts being presented and discussed, to display diagrams and figures too complex to draw on the chalkboard, and more recently to display computer…

  9. A Dynamic Duo: LCD Overhead Displays and Laptops as Instructional Aids in Introductory Psychology.

    ERIC Educational Resources Information Center

    Ransdell, Sarah

    1989-01-01

    Describes simulation software that was used with an LCD overhead display and laptop computers for large introductory psychology courses. The use of experiment simulators to increase student interest and activity is discussed, hardware is explained, and interaction between students, instructor, and the simulation is described. (14 references) (LRW)

  10. Water surface level profile estimation by image analysis with varying overhead camera posture angle

    NASA Astrophysics Data System (ADS)

    Hwung, H. H.; Kuo, C. A.; Chien, C. H.

    2009-07-01

    A digital CCD camera was used to capture and record the positions of the water surface at the sidewall of a wave flume by various angles of overhead posture. The wave image data were obtained using spatial transformation, image reconstruction and image detection processes. Two wave detection algorithms, which were the threshold method (TM) and the hyperbolic tangent function (HTF), were used to detect the water surface, and the detected results of the wave were compared with the measurement by a wave gauge. The results show that the wave surface detected by the HTF algorithm is better than that detected by the TM algorithm. The wave periods analyzed by the image data agreed very well with those of the wave gauges and the effect of variation of the overhead posture angle (θ) on wave period measurement was small. Since the pixel resolution increases with the overhead posture angle, however, the mean error of wave height measurement, which was analyzed by the TM algorithm, increased from 1.5% to 2.7% as θ changed from 15° to 45°. When θ was increased to 60°, the mean error of wave height rose to 4.7%. The mean error of wave height measurement, which was analyzed by the HTF algorithm, increased as the overhead posture angle increased, but the deviation was lower than that of the TM algorithm.

  11. Growth, nitrogen use efficiency, and leachate comparison of subirrigated and overhead irrigated pale purple coneflower seedlings

    Treesearch

    Jeremy R. Pinto; Rhiannon A. Chandler; R. Kasten Dumroese

    2008-01-01

    Pale purple coneflower [Echinacea pallida (Nutt.) Nutt.] was grown within three container volumes (90, 105, and 340 cm3) under subirrigation and overhead irrigation treatments. Subirrigated coneflowers showed increased seedling quality with more biomass (14%), better nitrogen use efficiency (13%), greater nitrogen content (N; 11%), more height (15...

  12. DETAIL OVERHEAD VIEW OF SECONDARY ORE BIN. CONVEYOR PLATFORM,TRAM TRESTLE, ...

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

    DETAIL OVERHEAD VIEW OF SECONDARY ORE BIN. CONVEYOR PLATFORM,TRAM TRESTLE, AND LOADING PLATFORM. LOOKING SOUTHWEST. THE HOLE IN THE ORE BIN FLOOR CAN BE SEEN, AND BALL MILL FOUNDATION AT LOWER LEFT CORNER. SEE CA-291-47(CT) FOR IDENTICAL COLOR TRANSPARENCY. - Keane Wonder Mine, Park Route 4 (Daylight Pass Cutoff), Death Valley Junction, Inyo County, CA

  13. Demonstrating Biological Principles Efficiently and Effectively: The Overhead Is More than Just a Lighted Chalkboard

    ERIC Educational Resources Information Center

    Barden-Gabbei, Laura M.

    2006-01-01

    The overhead projector is an excellent tool for teachers at both the high school and college level. Teachers often use it to display class notes as they monitor students' actions and reactions to the concepts being presented and discussed, to display diagrams and figures too complex to draw on the chalkboard, and more recently to display computer…

  14. Demonstrating Heat Changes on the Overhead Projector with a Projecting Thermometer.

    ERIC Educational Resources Information Center

    Hur, Chinhyu; Solomon, Sally; Wetzel, Christy

    1998-01-01

    Heat changes in a lecture setting can be safely shown on an overhead projector using a simple and inexpensive apparatus. Heat evolution can be observed on a projector with adapted digital thermometers or by illuminating the red fluid in nonmercury thermometers. Describes a setup for doing this as well as a collection of demonstrations involving…

  15. Using the Overhead Projector as a Light Source for Physics Demonstrations

    ERIC Educational Resources Information Center

    Mak, Se-Yuen

    2006-01-01

    This article illustrates how the overhead projector can be used as a light source in some peculiar ways for physics demonstrations. Five examples are included: (1) Study of chromatic aberration; (2) Making giant Newton's rings; (3) Comparison of the rate of heat absorption by different surfaces; (4) Demonstration of greenhouse effect; and (5)…

  16. 49 CFR 214.515 - Overhead covers for existing on-track roadway maintenance machines.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... maintenance machines. 214.515 Section 214.515 Transportation Other Regulations Relating to Transportation... Roadway Maintenance Machines and Hi-Rail Vehicles § 214.515 Overhead covers for existing on-track roadway maintenance machines. (a) For those existing on-track roadway maintenance machines either currently...

  17. 49 CFR 214.515 - Overhead covers for existing on-track roadway maintenance machines.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... maintenance machines. 214.515 Section 214.515 Transportation Other Regulations Relating to Transportation... Roadway Maintenance Machines and Hi-Rail Vehicles § 214.515 Overhead covers for existing on-track roadway maintenance machines. (a) For those existing on-track roadway maintenance machines either currently...

  18. 49 CFR 214.515 - Overhead covers for existing on-track roadway maintenance machines.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... maintenance machines. 214.515 Section 214.515 Transportation Other Regulations Relating to Transportation... Roadway Maintenance Machines and Hi-Rail Vehicles § 214.515 Overhead covers for existing on-track roadway maintenance machines. (a) For those existing on-track roadway maintenance machines either currently...

  19. 49 CFR 214.515 - Overhead covers for existing on-track roadway maintenance machines.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... maintenance machines. 214.515 Section 214.515 Transportation Other Regulations Relating to Transportation... Roadway Maintenance Machines and Hi-Rail Vehicles § 214.515 Overhead covers for existing on-track roadway maintenance machines. (a) For those existing on-track roadway maintenance machines either currently...

  20. 49 CFR 214.515 - Overhead covers for existing on-track roadway maintenance machines.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... maintenance machines. 214.515 Section 214.515 Transportation Other Regulations Relating to Transportation... Roadway Maintenance Machines and Hi-Rail Vehicles § 214.515 Overhead covers for existing on-track roadway maintenance machines. (a) For those existing on-track roadway maintenance machines either currently...

  1. 93. 22'X34' original blueprint, VariableAngle Launcher, 'OVERHEAD CAMERA SUSPENSION SYSTEM, ...

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

    93. 22'X34' original blueprint, Variable-Angle Launcher, 'OVERHEAD CAMERA SUSPENSION SYSTEM, TOWER STAY CABLES' drawn at 3/4'=1'-0'. (BUORD Sketch # 208783). - Variable Angle Launcher Complex, Variable Angle Launcher, CA State Highway 39 at Morris Reservior, Azusa, Los Angeles County, CA

  2. 76 FR 10476 - Special Conditions: Boeing Model 787-8 Airplane; Overhead Crew-Rest Compartment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-25

    ... Crew- Rest Compartment AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final special... will have novel or unusual design features associated with installation of an overhead crew-rest (OCR... Sec. 21.101. Novel or Unusual Design Features Crew-rest compartments have been installed...

  3. 77 FR 71697 - Safety Zone; Overhead Cable Replacement, Maumee River, Toledo, OH

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-04

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA08 Safety Zone; Overhead Cable Replacement, Maumee River... establishing a temporary Safety Zone on the waters of Maumee River, Toledo, Ohio, from 8:30 a.m. on November 27, 2012 until 6:30 p.m. on December 7, 2012. This safety zone will encompass all waters of Maumee River...

  4. Foam Overhead Cover Support (FOCOS) System for Dismounted and Mounted TOW Positions

    DTIC Science & Technology

    1979-08-01

    17 Decoy Positions Bouyancy /Hasty Pontoon Shelters 6 CONCLUSIONS ............................................. 17 FIGURES AND TABLES...the 1 INTRODUCTION U.S. Army Construction Engineering Research Laboratory (CERL) to provide a low- weight , low- Background volume overhead TOW cover...construction material for the TOW fighting positions is necessary to prevent simple and fast construction of low- weight , low- TOW weapons and crews

  5. 75 FR 44288 - Overhead and Gantry Cranes; Extension of the Office of Management and Budget's (OMB) Approval of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-28

    ... Occupational Safety and Health Administration Overhead and Gantry Cranes; Extension of the Office of Management...) approval of the information collection requirements specified in the Standard on Overhead and Gantry Cranes... paperwork provisions of the Standard specify requirements for: Marking the rated load of cranes; preparing...

  6. 77 FR 53914 - Horton Automatics, Inc., a Subsidiary of Overhead Door Corporation Including On-Site Leased...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-04

    ... Employment and Training Administration Horton Automatics, Inc., a Subsidiary of Overhead Door Corporation... Automatics, Inc., a subsidiary of Overhead Door Corporation, including on-site leased workers from Remedy... of automatic sliding, swinging, and revolving doors. The notice was published in the Federal Register...

  7. Methylation analysis of KvDMR1 in human oocytes

    PubMed Central

    Geuns, Elke; Hilven, Pierre; Van Steirteghem, André; Liebaers, Inge

    2007-01-01

    Recently, several reports have been published that showed a higher incidence of assisted reproductive technologies (ART) in patients with Beckwith–Wiedemann syndrome compared with the general population, and in most of these patients, aberrant methylation imprints of KvDMR1 have been found. This has led to the concern that ART might increase the incidence of imprinting syndromes such as Beckwith–Wiedemann syndrome. Not much is known on environmental or genetic factors that may interfere with the processes of imprint maintenance or resetting. A methylation analysis of KvDMR1 was performed in human oocytes at different stages of nuclear maturity and in sperm cells. The results indicate that the maternal methylation imprints were already established at the germinal vesicle stage, whereas all sperm cells were unmethylated, thereby showing that the KvDMR1 carries a germline methylation imprint. For one of the oocytes analysed, an unmethylated pattern was found, which highlights the need for further molecular studies that consider the safety of ART. PMID:16950814

  8. State-dependent inactivation of the Kv3 potassium channel.

    PubMed Central

    Marom, S; Levitan, I B

    1994-01-01

    Inactivation of Kv3 (Kv1.3) delayed rectifier potassium channels was studied in the Xenopus oocyte expression system. These channels inactivate slowly during a long depolarizing pulse. In addition, inactivation accumulates in response to a series of short depolarizing pulses (cumulative inactivation), although no significant inactivation occurs within each short pulse. The extent of cumulative inactivation does not depend on the voltage during the depolarizing pulse, but it does vary in a biphasic manner as a function of the interpulse duration. Furthermore, the rate of cumulative inactivation is influenced by changing the rate of deactivation. These data are consistent with a model in which Kv3 channel inactivation is a state-dependent and voltage-independent process. Macroscopic and single channel experiments indicate that inactivation can occur from a closed (silent) state before channel opening. That is, channels need not open to inactivate. The transition that leads to the inactivated state from the silent state is, in fact, severalfold faster then the observed inactivation of current during long depolarizing pulses. Long pulse-induced inactivation appears to be slow, because its rate is limited by the probability that channels are in the open state, rather than in the silent state from which they can inactivate. External potassium and external calcium ions alter the rates of cumulative and long pulse-induced inactivation, suggesting that antagonistic potassium and calcium binding steps are involved in the normal gating of the channel. PMID:7948675

  9. Return to Preinjury Levels of Participation After Superior Labral Repair in Overhead Athletes: A Systematic Review

    PubMed Central

    Sciascia, Aaron; Myers, Natalie; Kibler, W. Ben; Uhl, Timothy L.

    2015-01-01

    Context Athletes often preoperatively weigh the risks and benefits of electing to undergo an orthopaedic procedure to repair damaged tissue. A common concern for athletes is being able to return to their maximum levels of competition after shoulder surgery, whereas clinicians struggle with the ability to provide a consistent prognosis of successful return to participation after surgery. The variation in study details and rates of return in the existing literature have not supplied clinicians with enough evidence to give overhead athletes adequate information regarding successful return to participation when deciding to undergo shoulder surgery. Objective To investigate the odds of overhead athletes returning to preinjury levels of participation after arthroscopic superior labral repair. Data Sources The CINAHL, MEDLINE, and SPORTDiscus databases from 1972 to 2013. Study Selection The criteria for article selection were (1) The study was written in English. (2) The study reported surgical repair of an isolated superior labral injury or a superior labral injury with soft tissue debridement. (3) The study involved overhead athletes equal to or less than 40 years of age. (4) The study assessed return to the preinjury level of participation. Data Extraction We critically reviewed articles for quality and bias and calculated and compared odds ratios for return to full participation for dichotomous populations or surgical procedures. Data Synthesis Of 215 identified articles, 11 were retained: 5 articles about isolated superior labral repair and 6 articles about labral repair with soft tissue debridement. The quality range was 11 to 17 (42% to 70%) of a possible 24 points. Odds ratios could be generated for 8 of 11 studies. Nonbaseball, nonoverhead, and nonthrowing athletes had a 2.3 to 5.8 times greater chance of full return to participation than overhead/throwing athletes after isolated superior labral repair. Similarly, nonoverhead athletes had 1.5 to 3.5 times greater

  10. Extracellular chloride regulation of Kv2.1, contributor to the major outward Kv current in mammalian outer hair cells

    PubMed Central

    Li, Xiantao; Surguchev, Alexei; Bian, Shumin; Navaratnam, Dhasakumar

    2012-01-01

    Outer hair cells (OHC) function as both receptors and effectors in providing a boost to auditory reception. Amplification is driven by the motor protein prestin, which is under anionic control. Interestingly, we now find that the major, 4-AP-sensitive, outward K+ current of the OHC (IK) is also sensitive to Cl−, although, in contrast to prestin, extracellularly. IK is inhibited by reducing extracellular Cl− levels, with a linear dependence of 0.4%/mM. Other voltage-dependent K+ (Kv) channel conductances in supporting cells, such as Hensen and Deiters' cells, are not affected by reduced extracellular Cl−. To elucidate the molecular basis of this Cl−-sensitive IK, we looked at potential molecular candidates based on Cl− sensitivity and/or similarities in kinetics. For IK, we identified three different Ca2+-independent components of IK based on the time constant of inactivation: a fast, transient outward current, a rapidly activating, slowly inactivating current (Ik1), and a slowly inactivating current (Ik2). Extracellular Cl− differentially affects these components. Because the inactivation time constants of Ik1 and Ik2 are similar to those of Kv1.5 and Kv2.1, we transiently transfected these constructs into CHO cells and found that low extracellular Cl− inhibited both channels with linear current reductions of 0.38%/mM and 0.49%/mM, respectively. We also tested heterologously expressed Slick and Slack conductances, two intracellularly Cl−-sensitive K+ channels, but found no extracellular Cl− sensitivity. The Cl− sensitivity of Kv2.1 and its robust expression within OHCs verified by single-cell RT-PCR indicate that these channels underlie the OHC's extracellular Cl− sensitivity. PMID:21940671

  11. Coronary computed tomography angiography at 140 kV versus 120 kV: assessment of image quality and radiation exposure in overweight and moderately obese patients.

    PubMed

    Lee, Ashley M; Engel, Leif-Christopher; Hui, Gladwin C; Liew, Gary; Ferencik, Maros; Sidhu, Manavjot S; Hoffmann, Udo; Ghoshhajra, Brian B

    2014-06-01

    Although a tube potential of 140 kV is available on most computed tomography (CT) scanners, its incremental diagnostic value versus 120 kV has been controversial. To retrospectively evaluate the image quality and radiation exposure of cardiac computed tomography angiography (CCTA) performed at 140 kV in comparison to CCTA at 120 kV in overweight and moderately obese patients. Eighty-eight patients who were referred for CCTA between January 2010 and May 2012 were included. Forty-four patients who were overweight or moderately obese (body mass index [BMI], 25-35 kg/m(2)) underwent CCTA with dual-source CT (DSCT) scanner at 140 kV. Forty-four match controls who underwent CCTA with DSCT at 120 kV were identified per BMI, average heart rate, scan indication, and scan acquisition mode. All scans were performed per routine protocols with direct physician supervision. Quantitative image metrics (CT attenuation, image noise, contrast-to-noise ratio [CNR], and signal-to-noise ratio [SNR] of left main [LM] and proximal right coronary artery [RCA]) were assessed. Effective radiation dose was compared between the two groups. Overall, all scans were diagnostic without any non-evaluable coronary segment per clinical report. 140 kV had a lower attenuation and image noise versus 120 kV (P<0.01). Both SNR and CNR of proximal coronary arteries were similar between 140 kV and 120 kV (SNR, LM P=0.93, RCA P=0.62; CNR, LM P=0.57, RCA P=0.77). 140 kV was associated with a 35.3% increase in effective radiation dose as compared with 120 kV (5.1 [3.6-8.2] vs. 3.3 [2.0-5.1] mSv, respectively; P<0.01). 140 kV CCTA resulted in similar image quality but a higher effective radiation dose in comparison to 120 kV CCTA. Therefore, in overweight and moderately obese patients, a tube potential of 120 kV may be sufficient for CCTA with diagnostic image quality. © The Foundation Acta Radiologica 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  12. Properties and expression of Kv3 channels in cerebellar Purkinje cells.

    PubMed

    Sacco, Tiziana; De Luca, Annarita; Tempia, Filippo

    2006-10-01

    In cerebellar Purkinje cells, Kv3 potassium channels are indispensable for firing at high frequencies. In Purkinje cells from young mice (P4-P7), Kv3 currents, recorded in whole-cell in slices, activated at -30 mV, with rapid activation and deactivation kinetics, and they were partially blocked by blood depressing substance-I (BDS-I, 1 microM). At positive potentials, Kv3 currents were slowly but completely inactivating, while the recovery from inactivation was about eightfold slower, suggesting that a previous firing activity or a small change of the resting potential could in principle accumulate inactivated Kv3 channels, thereby finely tuning Kv3 current availability for subsequent action potentials. Single-cell RT-PCR analysis showed the expression by all Purkinje cells (n=10 for each subunit) of Kv3.1, Kv3.3 and Kv3.4 mRNA, while Kv3.2 was not expressed. These results add to the framework for interpreting the physiological function and the molecular determinants of Kv3 currents in cerebellar Purkinje cells.

  13. The Role of KV7.3 in Regulating Osteoblast Maturation and Mineralization

    PubMed Central

    Yang, Ji Eun; Song, Min Seok; Shen, Yiming; Ryu, Pan Dong; Lee, So Yeong

    2016-01-01

    KCNQ (KV7) channels are voltage-gated potassium (KV) channels, and the function of KV7 channels in muscles, neurons, and sensory cells is well established. We confirmed that overall blockade of KV channels with tetraethylammonium augmented the mineralization of bone-marrow-derived human mesenchymal stem cells during osteogenic differentiation, and we determined that KV7.3 was expressed in MG-63 and Saos-2 cells at the mRNA and protein levels. In addition, functional KV7 currents were detected in MG-63 cells. Inhibition of KV7.3 by linopirdine or XE991 increased the matrix mineralization during osteoblast differentiation. This was confirmed by alkaline phosphatase, osteocalcin, and osterix in MG-63 cells, whereas the expression of Runx2 showed no significant change. The extracellular glutamate secreted by osteoblasts was also measured to investigate its effect on MG-63 osteoblast differentiation. Blockade of KV7.3 promoted the release of glutamate via the phosphorylation of extracellular signal-regulated kinase 1/2-mediated upregulation of synapsin, and induced the deposition of type 1 collagen. However, activation of KV7.3 by flupirtine did not produce notable changes in matrix mineralization during osteoblast differentiation. These results suggest that KV7.3 could be a novel regulator in osteoblast differentiation. PMID:26999128

  14. Inhibition of Kv7/M Channel Currents by the Local Anesthetic Chloroprocaine.

    PubMed

    Zhang, Fan; Cheng, Yanxin; Li, Hong; Jia, Qingzhong; Zhang, Hailin; Zhao, Senming

    2015-01-01

    Chloroprocaine is a local ester anesthetic, producing excellent sensory block in clinical use. The Kv7/M potassium channel plays an important role in the control of neuronal excitability. In this study, we investigated the effects of the local anesthetic chloroprocaine on Kv7/M channels as well as the effect of retigabine on chloroprocaine-induced seizures. A perforated whole-cell patch technique was used to record Kv7 currents from HEK293 cells and M-type currents from rat dorsal root ganglion (DRG) neurons. Chloroprocaine produced a number of effects on Kv7.2/Kv7.3 currents, including a lowering of current amplitudes, a rightward shift in the voltage-dependent activation curves, and a slowing of channel activation. Chloroprocaine had a more selective inhibitory effect on the homomeric Kv7.3 and heteromeric Kv7.2/Kv7.3 channels than on the homomeric Kv7.2 channel. Chloroprocaine also inhibited native M channel currents and induced a depolarization of the DRG neuron membrane potential. Taken together, the findings indicate that chloroprocaine concentration dependently inhibited Kv7/M channel currents. © 2015 S. Karger AG, Basel.

  15. Dromedary immune response and specific Kv2.1 antibody generation using a specific immunization approach.

    PubMed

    Hassiki, Rym; Labro, Alain J; Benlasfar, Zakaria; Vincke, Cécile; Somia, Mahmoud; El Ayeb, Mohamed; Muyldermans, Serge; Snyders, Dirk J; Bouhaouala-Zahar, Balkiss

    2016-12-01

    Voltage-gated potassium (Kv) channels form cells repolarizing power and are commonly expressed in excitable cells. In non-excitable cells, Kv channels such as Kv2.1 are involved in cell differentiation and growth. Due to the involvement of Kv2.1 in several physiological processes, these channels are promising therapeutic targets. To develop Kv2.1 specific antibody-based channel modulators, we applied a novel approach and immunized a dromedary with heterologous Ltk- cells that overexpress the mouse Kv2.1 channel instead of immunizing with channel protein fragments. The advantage of this approach is that the channel is presented in its native tetrameric configuration. Using a Cell-ELISA, we demonstrated the ability of the immune serum to detect Kv2.1 channels on the surface of cells that express the channel. Then, using a Patch Clamp electrophysiology assay we explored the capability of the dromedary serum in modulating Kv2.1 currents. Cells that were incubated for 3h with serum taken at Day 51 from the start of the immunization displayed a statistically significant 2-fold reduction in current density compared to control conditions as well as cells incubated with serum from Day 0. Here we show that an immunization approach with cells overexpressing the Kv2.1 channel yields immune serum with Kv2.1 specific antibodies.

  16. Disruption of Kv1.3 Channel Forward Vesicular Trafficking by Hypoxia in Human T Lymphocytes*

    PubMed Central

    Chimote, Ameet A.; Kuras, Zerrin; Conforti, Laura

    2012-01-01

    Hypoxia in solid tumors contributes to decreased immunosurveillance via down-regulation of Kv1.3 channels in T lymphocytes and associated T cell function inhibition. However, the mechanisms responsible for Kv1.3 down-regulation are not understood. We hypothesized that chronic hypoxia reduces Kv1.3 surface expression via alterations in membrane trafficking. Chronic hypoxia decreased Kv1.3 surface expression and current density in Jurkat T cells. Inhibition of either protein synthesis or degradation and endocytosis did not prevent this effect. Instead, blockade of clathrin-coated vesicle formation and forward trafficking prevented the Kv1.3 surface expression decrease in hypoxia. Confocal microscopy revealed an increased retention of Kv1.3 in the trans-Golgi during hypoxia. Expression of adaptor protein-1 (AP1), responsible for clathrin-coated vesicle formation at the trans-Golgi, was selectively down-regulated by hypoxia. Furthermore, AP1 down-regulation increased Kv1.3 retention in the trans-Golgi and reduced Kv1.3 currents. Our results indicate that hypoxia disrupts AP1/clathrin-mediated forward trafficking of Kv1.3 from the trans-Golgi to the plasma membrane thus contributing to decreased Kv1.3 surface expression in T lymphocytes. PMID:22134923

  17. Developmental Expression of Kv Potassium Channels at the Axon Initial Segment of Cultured Hippocampal Neurons

    PubMed Central

    Sánchez-Ponce, Diana; DeFelipe, Javier; Garrido, Juan José; Muñoz, Alberto

    2012-01-01

    Axonal outgrowth and the formation of the axon initial segment (AIS) are early events in the acquisition of neuronal polarity. The AIS is characterized by a high concentration of voltage-dependent sodium and potassium channels. However, the specific ion channel subunits present and their precise localization in this axonal subdomain vary both during development and among the types of neurons, probably determining their firing characteristics in response to stimulation. Here, we characterize the developmental expression of different subfamilies of voltage-gated potassium channels in the AISs of cultured mouse hippocampal neurons, including subunits Kv1.2, Kv2.2 and Kv7.2. In contrast to the early appearance of voltage-gated sodium channels and the Kv7.2 subunit at the AIS, Kv1.2 and Kv2.2 subunits were tethered at the AIS only after 10 days in vitro. Interestingly, we observed different patterns of Kv1.2 and Kv2.2 subunit expression, with each confined to distinct neuronal populations. The accumulation of Kv1.2 and Kv2.2 subunits at the AIS was dependent on ankyrin G tethering, it was not affected by disruption of the actin cytoskeleton and it was resistant to detergent extraction, as described previously for other AIS proteins. This distribution of potassium channels in the AIS further emphasizes the heterogeneity of this structure in different neuronal populations, as proposed previously, and suggests corresponding differences in action potential regulation. PMID:23119056

  18. The Importance of Immunohistochemical Analyses in Evaluating the Phenotype of Kv Channel Knockout Mice

    PubMed Central

    Menegola, Milena; Clark, Eliana; Trimmer, James S.

    2012-01-01

    Summary To gain insights into the phenotype of Kv1.1 and Kv4.2 knockout mice, we used immunohistochemistry to analyze expression of component principal or α subunits and auxiliary subunits of neuronal Kv channels in knockout mouse brains. Genetic ablation of the Kv1.1 α subunit did not result in compensatory changes in the expression levels or subcellular distribution of related ion channel subunits in hippocampal medial perforant path and mossy fiber nerve terminals, where high levels of Kv1.1 are normally expressed. Genetic ablation of the Kv4.2 α subunit did not result in altered neuronal cytoarchitecture of the hippocampus. While Kv4.2 knockout mice did not exhibit compensatory changes in the expression levels or subcellular distribution of the related Kv4.3 α subunit, we found dramatic decreases in the cellular and subcellular expression of specific KChIPs that reflected their degree of association and colocalization with Kv4.2 in wild-type mouse and rat brains. These studies highlight the insights that can be gained by performing detailed immunohistochemical analyses of Kv channel knockout mouse brains. PMID:22612819

  19. Unconventional EGF-induced ERK1/2-mediated Kv1.3 endocytosis.

    PubMed

    Martínez-Mármol, Ramón; Comes, Núria; Styrczewska, Katarzyna; Pérez-Verdaguer, Mireia; Vicente, Rubén; Pujadas, Lluís; Soriano, Eduardo; Sorkin, Alexander; Felipe, Antonio

    2016-04-01

    The potassium channel Kv1.3 plays roles in immunity, neuronal development and sensory discrimination. Regulation of Kv1.3 by kinase signaling has been studied. In this context, EGF binds to specific receptors (EGFR) and triggers tyrosine kinase-dependent signaling, which down-regulates Kv1.3 currents. We show that Kv1.3 undergoes EGF-dependent endocytosis. This EGF-mediated mechanism is relevant because is involved in adult neural stem cell fate determination. We demonstrated that changes in Kv1.3 subcellular distribution upon EGFR activation were due to Kv1.3 clathrin-dependent endocytosis, which targets the Kv1.3 channels to the lysosomal degradative pathway. Interestingly, our results further revealed that relevant tyrosines and other interacting motifs, such as PDZ and SH3 domains, were not involved in the EGF-dependent Kv1.3 internalization. However, a new, and yet undescribed mechanism, of ERK1/2-mediated threonine phosphorylation is crucial for the EGF-mediated Kv1.3 endocytosis. Our results demonstrate that EGF triggers the down-regulation of Kv1.3 activity and its expression at the cell surface, which is important for the development and migration of adult neural progenitors.

  20. An engineered scorpion toxin analogue with improved Kv1.3 selectivity displays reduced conformational flexibility

    PubMed Central

    Bartok, Adam; Fehér, Krisztina; Bodor, Andrea; Rákosi, Kinga; Tóth, Gábor K.; Kövér, Katalin E.; Panyi, Gyorgy; Varga, Zoltan

    2015-01-01

    The voltage-gated Kv1.3 K+ channel plays a key role in the activation of T lymphocytes. Kv1.3 blockers selectively suppress immune responses mediated by effector memory T cells, which indicates the great potential of selective Kv1.3 inhibitors in the therapy of certain autoimmune diseases. Anuroctoxin (AnTx), a 35-amino-acid scorpion toxin is a high affinity blocker of Kv1.3, but also blocks Kv1.2 with similar potency. We designed and produced three AnTx variants: ([F32T]-AnTx, [N17A]-AnTx, [N17A/F32T]-AnTx) using solid-phase synthesis with the goal of improving the selectivity of the toxin for Kv1.3 over Kv1.2 while keeping the high affinity for Kv1.3. We used the patch-clamp technique to determine the blocking potency of the synthetic toxins on hKv1.3, mKv1.1, hKv1.2 and hKCa3.1 channels. Of the three variants [N17A/F32T]-AnTx maintained the high affinity of the natural peptide for Kv1.3 but became more than 16000-fold selective over Kv1.2. NMR data and molecular dynamics simulations suggest that the more rigid structure with restricted conformational space of the double substituted toxin compared to the flexible wild-type one is an important determinant of toxin selectivity. Our results provide the foundation for the possibility of the production and future therapeutic application of additional, even more selective toxins targeting various ion channels. PMID:26689143

  1. Developmental changes in the expression of calbindin and potassium-channel subunits Kv3.1b and Kv3.2 in mouse Renshaw cells.

    PubMed

    Song, Z-M; Hu, J; Rudy, B; Redman, S J

    2006-05-12

    One class of spinal interneurons, the Renshaw cells, is able to discharge at very high frequencies in adult mammals. Neuronal firing at such high frequencies requires voltage-gated potassium channels to rapidly repolarize the membrane potential after each action potential. We sought to establish the pattern of expression of calbindin and potassium channels with Kv3.1b and Kv3.2 subunits in Renshaw cells at different developmental stages of postnatal mice. The pattern of expression of calbindin changed dramatically during early postnatal development. An adult pattern of calbindin reactive neurons started to emerge from postnatal day 10 to postnatal day 14, with cells in laminae I and II of superficial dorsal horn and the ventral lamina VII. Renshaw cells were identified immunohistochemically by their expression of calbindin and their location in the ventral horn of the spinal cord. Western blot results of the lumbar spinal cord showed that Kv3.1b expression became faintly evident from postnatal day 10, reached a maximum at postnatal day 21 and was maintained through postnatal day 49. Double labeling results showed that all Renshaw cells expressed Kv3.1b weakly from postnatal day 14, and strongly at postnatal day 21. Western blot results showed that Kv3.2 expression became detectable in the lumbar cord from postnatal day 12, and increased steadily until reaching an adult level at postnatal day 28. In contrast to the Kv3.1b results, Kv3.2 was not expressed in Renshaw cells, although some neurons located at laminae VIII and VI expressed Kv3.2. We conclude that Renshaw cells express Kv3.1b but not Kv3.2 from postnatal day 14.

  2. Kv3.1/Kv3.2 channel positive modulators enable faster activating kinetics and increase firing frequency in fast-spiking GABAergic interneurons.

    PubMed

    Boddum, Kim; Hougaard, Charlotte; Xiao-Ying Lin, Julie; von Schoubye, Nadia Lybøl; Jensen, Henrik Sindal; Grunnet, Morten; Jespersen, Thomas

    2017-02-24

    Due to their fast kinetic properties, Kv3.1 voltage gated potassium channels are important in setting and controlling firing frequency in neurons and pivotal in generating high frequency firing of interneurons. Pharmacological activation of Kv3.1 channels may possess therapeutic potential for treatment of epilepsy, hearing disorders, schizophrenia and cognitive impairments. Here we thoroughly investigate the selectivity and positive modulation of the two small molecules, EX15 and RE01, on Kv3 channels. Selectivity studies, conducted in Xenopus laevis oocytes confirmed a positive modulatory effect of the two compounds on Kv3.1 and to a minor extent on Kv3.2 channels. RE01 had no effect on the Kv3.3 and Kv3.4 channels, whereas EX15 had an inhibitory impact on the Kv3.4 mediated current. Voltage-clamp experiments in monoclonal hKv3.1b/HEK293 cells (34 °C) revealed that the two compounds indeed induced larger currents and faster activation kinetics. They also decrease the speed of deactivation and shifted the voltage dependence of activation, to a more negative activation threshold. Application of action potential clamping and repetitive stimulation protocols of hKv3.1b expressing HEK293 cells revealed that EX15 and RE01 significantly increased peak amplitude, half width and decay time of Kv3.1 mediated currents, even during high-frequency action potential clamping (250 Hz). In rat hippocampal slices, EX15 and RE01 increased neuronal excitability in fast-spiking interneurons in dentate gyrus. Action potential frequency was prominently increased at minor depolarizing steps, whereas more marginal effects of EX15 and RE01 were observed after stronger depolarizations. In conclusion, our results suggest that EX15 and RE01 positive modulation of Kv3.1 and Kv3.2 currents facilitate increased firing frequency in fast-spiking GABAergic interneurons.

  3. Kv1 channels selectively prevent dendritic hyperexcitability in rat Purkinje cells

    PubMed Central

    Khavandgar, Simin; Walter, Joy T; Sageser, Kristin; Khodakhah, Kamran

    2005-01-01

    Purkinje cells, the sole output of the cerebellar cortex, encode the timing signals required for motor coordination in their firing rate and activity pattern. Dendrites of Purkinje cells express a high density of P/Q-type voltage-gated calcium channels and fire dendritic calcium spikes. Here we show that dendritic subthreshold Kv1.2 subunit-containing Kv1 potassium channels prevent generation of random spontaneous calcium spikes. With Kv1 channels blocked, dendritic calcium spikes drive bursts of somatic sodium spikes and prevent the cell from faithfully encoding motor timing signals. The selective dendritic function of Kv1 channels in Purkinje cells allows them to effectively suppress dendritic hyperexcitability without hindering the generation of somatic action potentials. Further, we show that Kv1 channels also contribute to dendritic integration of parallel fibre synaptic input. Kv1 channels are often targeted to soma and axon and the data presented support a major dendritic function for these channels. PMID:16210348

  4. KV7 channels in the human detrusor: channel modulator effects and gene and protein expression.

    PubMed

    Bientinesi, Riccardo; Mancuso, Cesare; Martire, Maria; Bassi, Pier Francesco; Sacco, Emilio; Currò, Diego

    2017-02-01

    Voltage-gated type 7 K(+) (KV7 or KCNQ) channels regulate the contractility of various smooth muscles. With this study, we aimed to assess the role of KV7 channels in the regulation of human detrusor contractility, as well as the gene and protein expression of KV7 channels in this tissue. For these purposes, the isolated organ technique, RT-qPCR, and Western blot were used, respectively. XE-991, a selective KV7 channel blocker, concentration-dependently contracted the human detrusor; mean EC50 and Emax of XE-991-induced concentration-response curve were 14.1 μM and 28.8 % of the maximal bethanechol-induced contraction, respectively. Flupirtine and retigabine, selective KV7.2-7.5 channel activators, induced concentration-dependent relaxations of bethanechol-precontracted strips, with maximal relaxations of 51.6 and 51.8 % of the precontraction, respectively. XE-991 blocked the relaxations induced by flupirtine and retigabine. All five KCNQ genes were found to be expressed in the detrusor with KCNQ4 being the most expressed among them. Different bands, having sizes similar to some of reported KV7.1, 7.4, and 7.5 channel subunit isoforms, were detected in the detrusor by Western blot with the KV7.4 band being the most intense among them. In conclusion, KV7 channels contribute to set the basal tone of the human detrusor. In addition, KV7 channel activators significantly relax the detrusor. The KV7.4 channels are probably the most important KV7 channels expressed in the human detrusor. These data suggest that selective KV7.4 channel activators might represent new pharmacological tools for inducing therapeutic relaxation of the detrusor.

  5. Cellular mechanisms and behavioral consequences of Kv1.2 regulation in the rat cerebellum

    PubMed Central

    Williams, Michael R; Fuchs, Jason R; Green, John T; Morielli, Anthony D

    2012-01-01

    The potassium channel Kv1.2 alpha-subunit is expressed in cerebellar Purkinje cell (PC) dendrites where its pharmacological inhibition increases excitability (Khavandgar et al., 2005). Kv1.2 is also expressed in cerebellar basket cell (BC) axon terminals (Sheng et al., 1994), where its blockade increases BC inhibition of PCs (Southan and Robertson, 1998a). Secretin receptors are also expressed both in PC dendrites and BC axon terminals (reviewed in (Yuan et al.). The effect of secretin on PC excitability is not yet known, but, like Kv1.2 inhibitors, secretin potently increases inhibitory input to PCs (Yung et al., 2001). This suggests secretin may act in part by suppressing Kv1.2. Receptor-mediated endocytosis is a mechanism of Kv1.2 suppression (Nesti et al., 2004). This process can be regulated by protein kinase A (PKA) (Connors et al., 2008). Since secretin receptors activate PKA (Wessels-Reiker et al., 1993), we tested the hypothesis that secretin regulates Kv1.2 trafficking in the cerebellum. Using cell surface protein biotinylation of rat cerebellar slices, we found secretin decreased cell-surface Kv1.2 levels by modulating Kv1.2 endocytic trafficking. This effect was mimicked by activating adenylate cyclase (AC) with forskolin, and was blocked by pharmacological inhibitors of AC or PKA. Imaging studies identified the BC axon terminal and Purkinje cell dendrites as loci of AC-dependent Kv1.2 trafficking. The physiological significance of secretin regulated Kv1.2 endocytosis is supported by our finding that infusion into the cerebellar cortex of either the Kv1.2 inhibitor Tityustoxin-Kα, or of the Kv1.2 regulator secretin, significantly enhances acquisition of eyeblink conditioning in rats. PMID:22764231

  6. Kv4.2 knockout mice demonstrate increased susceptibility to convulsant stimulation

    PubMed Central

    Barnwell, L. Forbes S.; Lugo, Joaquin N.; Lee, Wai Ling; Willis, Sarah E.; Gertz, Shira J.; Hrachovy, Richard A.; Anderson, Anne E.

    2010-01-01

    Purpose Kv4.2 subunits contribute to the pore-forming region of channels that express a transient, A-type K+ current (A-current) in hippocampal CA1 pyramidal cell dendrites. Here, the A-current plays an important role in signal processing and synaptic integration. Kv4.2 knockout mice show a near elimination of the A-current in area CA1 dendrites producing increased excitability in this region. In these studies, we evaluated young adult Kv4.2 knockout mice for spontaneous seizures and the response to convulsant stimulation in the whole animal in vivo and in hippocampal slices in vitro. Methods Electroencephalogram electrode-implanted Kv4.2 knockout and wildtype mice were observed for spontaneous behavioral and electrographic seizures. The latency to seizure and status epilepticus onset in Kv4.2 knockout and wildtype mice was assessed following intraperitoneal injection of kainate. Extracellular field potential recordings were performed in hippocampal slices from Kv4.2 knockout and wildtype mice following the bath application of bicuculline. Results No spontaneous behavioral or electrographic seizures were observed in Kv4.2 knockout mice. Following kainate, Kv4.2 knockout mice demonstrated a decreased seizure and status epilepticus latency as well as increased mortality compared to wildtype littermates. The background strain modified the seizure susceptibility phenotype in Kv4.2 knockout mice. In response to bicuculline, slices from Kv4.2 knockout mice exhibited an increase in epileptiform bursting in area CA1 as compared to wildtype littermates. Discussion These studies show that loss of Kv4.2 channels is associated with enhanced susceptibility to convulsant stimulation, supporting the concept that Kv4.2 deficiency may contribute to aberrant network excitability and regulate seizure threshold. PMID:19453702

  7. Mapping the Interaction Anatomy of BmP02 on Kv1.3 Channel

    PubMed Central

    Wu, B.; Wu, B. F.; Feng, Y. J.; Tao, J.; Ji, Y. H.

    2016-01-01

    The potassium channel Kv 1.3 plays a vital part in the activation of T lymphocytes and is an attractive pharmacological target for autoimmune diseases. BmP02, a 28-residue peptide isolated from Chinese scorpion (Buthus martensi Karsch) venom, is a potent and selective Kv1.3 channel blocker. However, the mechanism through which BmP02 recognizes and inhibits the Kv1.3 channel is still unclear. In the present study, a complex molecular model of Kv1.3-BmP02 was developed by docking analysis and molecular dynamics simulations. From these simulations, it appears the large β-turn (residues 10–16) of BmP02 might be the binding interface with Kv 1.3. These results were confirmed by scanning alanine mutagenesis of BmP02, which identified His9, Lys11 and Lys13, which lie within BmP02’s β-turn, as key residues for interacting with Kv1.3. Based on these results and molecular modeling, two negatively charged residues of Kv1.3, D421 and D422, located in turret region, were predicted to act as the binding site for BmP02. Mutation of these residues reduced sensitivity of Kv 1.3 to BmP02 inhibition, suggesting that electrostatic interactions play a crucial role in Kv1.3-BmP02 interaction. This study revealed the molecular basis of Kv 1.3 recognition by BmP02 venom, and provides a novel interaction model for Kv channel-specific blocker complex, which may help guide future drug-design for Kv1.3-related channelopathies. PMID:27403813

  8. Mapping the Interaction Anatomy of BmP02 on Kv1.3 Channel

    NASA Astrophysics Data System (ADS)

    Wu, B.; Wu, B. F.; Feng, Y. J.; Tao, J.; Ji, Y. H.

    2016-07-01

    The potassium channel Kv 1.3 plays a vital part in the activation of T lymphocytes and is an attractive pharmacological target for autoimmune diseases. BmP02, a 28-residue peptide isolated from Chinese scorpion (Buthus martensi Karsch) venom, is a potent and selective Kv1.3 channel blocker. However, the mechanism through which BmP02 recognizes and inhibits the Kv1.3 channel is still unclear. In the present study, a complex molecular model of Kv1.3-BmP02 was developed by docking analysis and molecular dynamics simulations. From these simulations, it appears the large β-turn (residues 10–16) of BmP02 might be the binding interface with Kv 1.3. These results were confirmed by scanning alanine mutagenesis of BmP02, which identified His9, Lys11 and Lys13, which lie within BmP02’s β-turn, as key residues for interacting with Kv1.3. Based on these results and molecular modeling, two negatively charged residues of Kv1.3, D421 and D422, located in turret region, were predicted to act as the binding site for BmP02. Mutation of these residues reduced sensitivity of Kv 1.3 to BmP02 inhibition, suggesting that electrostatic interactions play a crucial role in Kv1.3-BmP02 interaction. This study revealed the molecular basis of Kv 1.3 recognition by BmP02 venom, and provides a novel interaction model for Kv channel-specific blocker complex, which may help guide future drug-design for Kv1.3-related channelopathies.

  9. Expression and function of K(V)2-containing channels in human urinary bladder smooth muscle.

    PubMed

    Hristov, Kiril L; Chen, Muyan; Afeli, Serge A Y; Cheng, Qiuping; Rovner, Eric S; Petkov, Georgi V

    2012-06-01

    The functional role of the voltage-gated K(+) (K(V)) channels in human detrusor smooth muscle (DSM) is largely unexplored. Here, we provide molecular, electrophysiological, and functional evidence for the expression of K(V)2.1, K(V)2.2, and the electrically silent K(V)9.3 subunits in human DSM. Stromatoxin-1 (ScTx1), a selective inhibitor of K(V)2.1, K(V)2.2, and K(V)4.2 homotetrameric channels and of K(V)2.1/9.3 heterotetrameric channels, was used to examine the role of these channels in human DSM function. Human DSM tissues were obtained during open bladder surgeries from patients without a history of overactive bladder. Freshly isolated human DSM cells were studied using RT-PCR, immunocytochemistry, live-cell Ca(2+) imaging, and the perforated whole cell patch-clamp technique. Isometric DSM tension recordings of human DSM isolated strips were conducted using tissue baths. RT-PCR experiments showed mRNA expression of K(V)2.1, K(V)2.2, and K(V)9.3 (but not K(V)4.2) channel subunits in human isolated DSM cells. K(V)2.1 and K(V)2.2 protein expression was confirmed by Western blot analysis and immunocytochemistry. Perforated whole cell patch-clamp experiments revealed that ScTx1 (100 nM) inhibited the amplitude of the voltage step-induced K(V) current in freshly isolated human DSM cells. ScTx1 (100 nM) significantly increased the intracellular Ca(2+) level in DSM cells. In human DSM isolated strips, ScTx1 (100 nM) increased the spontaneous phasic contraction amplitude and muscle force, and enhanced the amplitude of the electrical field stimulation-induced contractions within the range of 3.5-30 Hz stimulation frequencies. These findings reveal that ScTx1-sensitive K(V)2-containing channels are key regulators of human DSM excitability and contractility and may represent new targets for pharmacological or genetic intervention for bladder dysfunction.

  10. Localization of Kv1.3 channels in presynaptic terminals of brainstem auditory neurons

    PubMed Central

    Gazula, Valeswara-Rao; Strumbos, John G.; Mei, Xiaofeng; Chen, Haijun; Rahner, Christoph; Kaczmarek, Leonard K.

    2010-01-01

    Elimination of the Kv1.3 voltage-dependent potassium channel gene produces striking changes in the function of the olfactory bulb, raising the possibility that this channel also influences other sensory systems. We have examined the cellular and subcellular localization of Kv1.3 in the Medial Nucleus of the Trapezoid Body (MNTB) in the auditory brainstem, a nucleus in which neurons fire at high rates with high temporal precision. A clear gradient of Kv1.3 immunostaining along the lateral to medial tonotopic axis of the MNTB was detected. Highest levels were found in the lateral region of the MNTB, which corresponds to neurons that respond selectively to low frequency auditory stimuli. Previous studies have demonstrated that MNTB neurons and their afferent inputs from the cochlear nucleus express three other members of the Kv1 family, Kv1.1, Kv1.2 and Kv1.6. Nevertheless, confocal microscopy of MNTB sections co-immunostained for Kv1.3 with these subunits revealed that the distribution of Kv1.3 differed significantly from other Kv1 family subunits. In particular, no axonal staining of Kv1.3 was detected and most prominent labeling was in structures surrounding the somata of the principal neurons, suggesting specific localization to the large calyx of Held presynaptic endings that envelop the principal cells. The presence of Kv1.3 in presynaptic terminals was confirmed by co-immunolocalization with the synaptic markers synaptophysin, syntaxin, and synaptotagmin and by immunogold electron microscopy. Kv1.3 immunogold particles in the terminals were arrayed along the plasma membrane and on internal vesicular structures. To confirm these patterns of staining, we carried out immunolabeling on sections from Kv1.3−/− mice. No immunoreactivity could be detected in Kv1.3−/− mice either at the light level or in immunogold experiments. The finding of a tonotopic gradient in presynaptic terminals suggests that Kv1.3 may regulate neurotransmitter release differentially in

  11. Bab Eshtar Substation 11 kV Feeder Cable. Mosul, Iraq

    DTIC Science & Technology

    2006-10-17

    Item Unit QTY U price Total in US$ 3x150mm2 , 11kv , XLPE insulated cable M 10,000 43 430000 Straight outdoor heat shrinkable splice kit for 3x150mm2...11kv, XLPE cable Ea 15 325 4875 Indoor Heat shrinkable termination kit for 3x150mm2, 11kv XLPE cable Ea 9 250 2250 Outdoor Heat shrinkable...termination kit for 3x150mm2, 11kv XLPE cable Ea 5 275 1375 2 Ring-main feeders with cabinet Ea 2 18000 36000 Excavated sand m3 550 30 16500 Fine soil m3 350

  12. The C-terminus of Kv7 channels: a multifunctional module.

    PubMed

    Haitin, Yoni; Attali, Bernard

    2008-04-01

    Kv7 channels (KCNQ) represent a family of voltage-gated K(+) channels which plays a prominent role in brain and cardiac excitability. Their physiological importance is underscored by the existence of mutations in human Kv7 genes, leading to severe cardiovascular and neurological disorders such as the cardiac long QT syndrome and neonatal epilepsy. Kv7 channels exhibit some structural and functional features that are distinct from other Kv channels. Notably, the Kv7 C-terminus is long compared to other K(+) channels and is endowed with characteristic structural domains, including coiled-coils, amphipatic alpha helices containing calmodulin-binding motifs and basic amino acid clusters. Here we provide a brief overview of current insights and as yet unsettled issues about the structural and functional attributes of the C-terminus of Kv7 channels. Recent data indicate that the proximal half of the Kv7 C-terminus associates with one calmodulin constitutively bound to each subunit. Epilepsy and long QT mutations located in this proximal region impair calmodulin binding and can affect channel gating, folding and trafficking. The distal half of the Kv7 C-terminus directs tetramerization, employing tandem coiled-coils. Together, the data indicate that the Kv7 C-terminal domain is a multimodular structure playing a crucial role in channel gating, assembly and trafficking as well as in scaffolding the channel complex with signalling proteins.

  13. Potassium channel Kv1.3 is highly expressed by microglia in human Alzheimer's disease.

    PubMed

    Rangaraju, Srikant; Gearing, Marla; Jin, Lee-Way; Levey, Allan

    2015-01-01

    Recent genetic studies suggest a central role for innate immunity in Alzheimer's disease (AD) pathogenesis, wherein microglia orchestrate neuroinflammation. Kv1.3, a voltage-gated potassium channel of therapeutic relevance in autoimmunity, is upregulated by activated microglia and mediates amyloid-mediated microglial priming and reactive oxygen species production in vitro. We hypothesized that Kv1.3 channel expression is increased in human AD brain tissue. In a blinded postmortem immunohistochemical semi-quantitative analysis performed on ten AD patients and ten non-disease controls, we observed a significantly higher Kv1.3 staining intensity (p = 0.03) and Kv1.3-positive cell density (p = 0.03) in the frontal cortex of AD brains, compared to controls. This paralleled an increased number of Iba1-positive microglia in AD brains. Kv1.3-positive cells had microglial morphology and were associated with amyloid-β plaques. In immunofluorescence studies, Kv1.3 channels co-localized primarily with Iba1 but not with astrocyte marker GFAP, confirming that elevated Kv1.3 expression is limited to microglia. Higher Kv1.3 expression in AD brains was also confirmed by western blot analysis. Our findings support that Kv1.3 channels are biologically relevant and microglia-specific targets in human AD.

  14. Activation of KV7 channels stimulates vasodilatation of human placental chorionic plate arteries.

    PubMed

    Mills, T A; Greenwood, S L; Devlin, G; Shweikh, Y; Robinson, M; Cowley, E; Hayward, C E; Cottrell, E C; Tropea, T; Brereton, M F; Dalby-Brown, W; Wareing, M

    2015-06-01

    Potassium (K(+)) channels are key regulators of vascular smooth muscle cell (VSMC) excitability. In systemic small arteries, Kv7 channel expression/activity has been noted and a role in vascular tone regulation demonstrated. We aimed to demonstrate functional Kv7 channels in human fetoplacental small arteries. Human placental chorionic plate arteries (CPAs) were obtained at term. CPA responses to Kv7 channel modulators was determined by wire myography. Presence of Kv7 channel mRNA (encoded by KCNQ1-5) and protein expression were assessed by RT-PCR and immunohistochemistry/immunofluorescence, respectively. Kv7 channel blockade with linopirdine increased CPA basal tone and AVP-induced contraction. Pre-contracted CPAs (AVP; 80 mM K(+) depolarization solution) exhibited significant relaxation to flupirtine, retigabine, the acrylamide (S)-1, and (S) BMS-204352, differential activators of Kv7.1 - Kv7.5 channels. All CPAs assessed expressed KCNQ1 and KCNQ3-5 mRNA; KCNQ2 was expressed only in a subset of CPAs. Kv7 protein expression was confirmed in intact CPAs and isolated VSMCs. Kv7 channels are present and active in fetoplacental vessels, contributing to vascular tone regulation in normal pregnancy. Targeting these channels may represent a therapeutic intervention in pregnancies complicated by increased vascular resistance. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Measuring Occupational Exposure to Extremely Low-Frequency Electric Fields at 220 kV Substations.

    PubMed

    Pirkkalainen, Herkko; Heiskanen, Timo; Tonteri, Juhani; Elovaara, Jarmo; Mika, Penttilä; Korpinen, Leena

    2017-03-03

    Earlier studies conducted at 400 and 110 kV substations in Finland have shown that the occupational exposure to electric fields can exceed the action levels (ALs) set by Directive 2013/35/EU. This is a case study investigating the level of occupational exposure experienced by workers at 220 kV substations in order to determine if the actions levels are being exceeded. The measurements were conducted at two old 220 kV substations in Finland. The higher AL of 20 kV m-1 was exceeded at both substations.

  16. 30-kV proton injector for PIGMI

    SciTech Connect

    Hamm, R.W.; Mueller, D.W.; Sturgess, R.G.

    1981-01-01

    A 30-kV proton injector designed for matching a 31-mA proton beam into the radio-frequency quadrupole (RFQ) section of the PIGMI accelerator has been constructed and tested. This injector uses a small efficient duoplasmatron ion source and a single-gap extraction system for creating a convergent ion beam, and a three-element unipotential einzel lens for focusing the ion beam into the RFQ. A description of this prototype injector is presented, along with the experimental data obtained during the testing of this system.

  17. Pollution performance of 110 kV metal oxide arresters

    SciTech Connect

    Chrzan, K.; Pohl, Z.; Grzybowski, S.; Koehler, W.

    1997-04-01

    Pollution test results of single unit 110 kV metal oxide surge arresters with porcelain housing according to the solid layer and salt fog methods are presented. During 6 hours of testing, the internal and external charge and maximum temperature along the varistor column were measured. The formation of single stable dry bands on the housing was often observed, especially during salt fog tests. In such cases, the varistor temperature can reach about 70 C. The simple electrical model of the arrester enabling calculations of voltages and currents as a function of arrester and pollution parameters is shown.

  18. 10-Joule 200 kV Mini Marx

    DTIC Science & Technology

    1985-06-01

    A low-energy Marx generator was designed at Los Alamos as a spark gap trigger. Since the initial report1 the design has been improved and is now...manufactured commercially. The Mini Marx has a risetime of less than 2 ns to over 200 kV measured in to a 23 omega load. The power output approaches one...gigawatt. The Mini Marx can multichannel field distortion gaps or fire a number of gaps with little gap-to-gap isolation. It has also been used to

  19. V4641 Sgr and KV UMa. Two black hole candidates

    NASA Astrophysics Data System (ADS)

    Chuprikov, A.; Guirin, I.

    We have analized the results of processing of the NRAO archive VLA and VLBA data for two star objects titled V4641 Sgr (J1819-2524) and KV UMa (X1118+4802). Some radio images of both sources for some frequency ranges are presented. Data have been processed with the software project titled 'Astro Space Locator' (ASL for Windows). The Multi Frequency Synthesis (MFS) method has been used for reconstruction of radio maps. Images of both sources are presented. Any polarization phenomena are not taken into account. We present results of processing of data of RR polarization for all the observational sessions.

  20. Evaluation of Audible Noise from Surface Processing Conductors for AC Overhead Transmission Line

    NASA Astrophysics Data System (ADS)

    Miyajima, Kiyotomi; Tanabe, Kazuo

    Corona discharge may cause audible noise, and it is frequently generated from wet conductors of high-voltage AC overhead transmission lines. Audible noise arises more easily from new conductors that have lubricating oil on their surface than from aged conductors. In this paper, the corona characteristics, particularly audible noise, of conductors having various wetting properties is presented developing a corona-free conductor for AC overhead transmission lines. It was found that a conductor having a super-hydrophobic surface exhibited a minimized audible noise level, but it does not have sufficient durability for practical application. Furthermore, a conductor having a super-hydrophilic surface made by thermal spraying of TiO2 showed good performance regarding the suppression of audible noise. The thermal spraying of TiO2 seems to be an effective processing technique that has sufficient durability for practical application.

  1. A fuzzy-logic antiswing controller for three-dimensional overhead cranes.

    PubMed

    Cho, Sung-Kun; Lee, Ho-Hoon

    2002-04-01

    In this paper, a new fuzzy antiswing control scheme is proposed for a three-dimensional overhead crane. The proposed control consists of a position servo control and a fuzzy-logic control. The position servo control is used to control crane position and rope length, and the fuzzy-logic control is used to suppress load swing. The proposed control guarantees not only prompt suppression of load swing but also accurate control of crane position and rope length for simultaneous travel, traverse, and hoisting motions of the crane. Furthermore, the proposed control provides practical gain tuning criteria for easy application. The effectiveness of the proposed control is shown by experiments with a three-dimensional prototype overhead crane.

  2. Partial feedback linearization control for 3-D underactuated overhead crane systems.

    PubMed

    Wu, Xianqing; He, Xiongxiong

    2016-11-01

    In this paper, a novel anti-swing control method is proposed for 3-dimensional (3-D) underactuated overhead crane systems, which guarantees fast transportation and efficient swing suppression. Specifically, to increase the performance of the payload swing suppression, a swing-suppressing element is introduced, based on which a novel positioning error signal is constructed. Then, a new control method is developed, and the overall system is divided into two subsystems. The stability analysis of the two subsystems and the overall system is given. In addition, the convergence of the system states is proved. Simulation results are provided to demonstrate the superior performance of the proposed controller over the existing controllers. Meanwhile, the practical performance of the proposed controller is experimentally validated on a portable overhead crane test-bed. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  3. A low overhead load balancing router for network-on-chip

    NASA Astrophysics Data System (ADS)

    Xiaofeng, Zhou; Lu, Liu; Zhangming, Zhu; Duan, Zhou

    2016-11-01

    The design of a router in a network-on-chip (NoC) system has an important impact on some performance criteria. In this paper, we propose a low overhead load balancing router (LOLBR) for 2D mesh NoC to enhance routing performance criteria with low hardware overhead. The proposed LOLBR employs a balance toggle identifier to control the initial routing direction of X or Y for flit injection. The simplified demultiplexers and multiplexers are used to handle output ports allocation and contention, which provide a guarantee of deadlock avoidance. Simulation results show that the proposed LOLBR yields an improvement of routing performance over the reported routing schemes in average packet latency by 26.5%. The layout area and power consumption of the network compared with the reported routing schemes are 15.3% and 11.6% less respectively. Project supported by the National Natural Science Foundation of China (Nos. 61474087, 61322405, 61376039).

  4. 3-D Object Recognition Using Combined Overhead And Robot Eye-In-Hand Vision System

    NASA Astrophysics Data System (ADS)

    Luc, Ren C.; Lin, Min-Hsiung

    1987-10-01

    A new approach for recognizing 3-D objects using a combined overhead and eye-in-hand vision system is presented. A novel eye-in-hand vision system using a fiber-optic image array is described. The significance of this approach is the fast and accurate recognition of 3-D object information compared to traditional stereo image processing. For the recognition of 3-D objects, the over-head vision system will take 2-D top view image and the eye-in-hand vision system will take side view images orthogonal to the top view image plane. We have developed and demonstrated a unique approach to integrate this 2-D information into a 3-D representation based on a new approach called "3-D Volumetric Descrip-tion from 2-D Orthogonal Projections". The Unimate PUMA 560 and TRAPIX 5500 real-time image processor have been used to test the success of the entire system.

  5. Do overhead sports increase risk for rotator cuff tears in wheelchair users?

    PubMed

    Akbar, Michael; Brunner, Manuela; Ewerbeck, Volker; Wiedenhöfer, Bernd; Grieser, Thomas; Bruckner, Thomas; Loew, Markus; Raiss, Patric

    2015-03-01

    To analyze whether frequent overhead-sports activity increases the risk for rotator cuff disease in patients with spinal cord injuries (SCIs) who are wheelchair dependent. Cross-sectional study, risk analysis. Department of Orthopaedic Surgery, Trauma Surgery and Spinal Cord Injury. Patients (N=296) with SCI requiring the full-time use of a manual wheelchair were recruited for this study. The total population was divided into 2 groups (sports vs no sports), among them 103 patients playing overhead sports on a regular basis (at least 1-2 times/wk) and 193 patients involved in overhead sports less than once a week or in no sports activity at all. The mean age of the sports group was 49.1 years. The mean duration of wheelchair dependence was 26.5 years. The mean age of the no-sports group was 48 years. The mean duration of wheelchair dependence was 25.2 years. Each individual completed a questionnaire designed to identify overhead-sports activity on a regular basis and was asked about shoulder problems. Magnetic resonance imaging scans of both shoulders were performed in each patient and analyzed in a standardized fashion. None. Possible differences in continuous data between patients with and without rotator cuff tear were evaluated. The relative risk of suffering from a rotator cuff tear between patients playing overhead sports and those not playing overhead sports was calculated. One hundred three patients played overhead sports regularly and 193 did not. There was no difference between groups regarding age, sex, level of SCI, and duration of wheelchair dependence. The body mass index was significantly lower in the sports group than in the no-sports group (P<.0001). A rotator cuff tear was present in 75.7% of the patients in the sports group and in 36.3% of the patients in the no-sports group (P<.0001). Rotator cuff tears were symptomatic in 92.6% of the patients. The estimated risk increase for the sports group to develop rotator cuff tears was twice as high as

  6. A Full Overhead Cost Model for the U.S. Coast Guard Yard, Curtis Bay, Maryland.

    DTIC Science & Technology

    1982-06-01

    AD-AI19 337 NAVAL POSTGRADUATE SCHOOL TONTZRME CA F/G 5/1 A FULL OVERHEAD COST MODEL FOR THE U.S. COAST WARD YARD, CURTI--ETC( U ) U N C L A S S IF I E...ment, social security (FICA), life insurance (FEGLIA), and health insurance (FEHBA). J Overhead is charged to customers as a percentage of direct...I U C4 1 c 4co0 0N.-4 Y4 AO (E1 t9 0 ’, 0 r4I~ i ’ 0 1* .o -0 r- M 0 ,-e- df nj H- S Ln A (I 0 _5 r 41 . 5 .. ’n "’n ! ji fn Ci53 -W a %0 l. M a;W

  7. A Hybrid Method for Evaluating of Lightning Performance of Overhead Lines based on Monte Carlo Procedure

    NASA Astrophysics Data System (ADS)

    Shariatinasab, Reza; Tadayon, Pooya; Ametani, Akihiro

    2016-07-01

    This paper proposes a hybrid method for calculating lightning performance of overhead lines caused by direct strokes by combining Lattice diagram together with the Monte Carlo method. In order to go through this, firstly, the proper analytical relations for overvoltages calculation are established based on Lattice diagram. Then, the Monte Carlo procedure is applied to the obtained analytical relations. The aim of the presented method that will be called `ML method' is simply estimation of the lightning performance of the overhead lines and performing the risk analysis of power apparatus with retaining the acceptable accuracy. To confirm the accuracy, the calculated results of the presented ML method are compared with those calculated by the EMTP/ATP simulation.

  8. Evaluation of overhead guide sign sheeting materials to increase visibility and safety for drivers.

    PubMed

    Obeidat, Mohammed Said; Rys, Malgorzata J; Rys, Andrew; Du, Juan

    2016-09-01

    Overhead guide sign visibility must increase to improve driver safety on roadways. Two methods increase overhead guide sign visibility: sign illumination and use of retroreflective sheeting materials. This paper compares three types of retroreflective sheeting: Engineering Grade (type I), Diamond Grade (type XI), and High Intensity (type IV). A field experiment was conducted at night using licensed drivers to determine the optimum retroreflective sheeting material that increases sign visibility and legibility. Results showed that, of the three types of retroreflective sheeting, Diamond Grade (type XI) sheeting requires minimum illuminance to be visible, followed by High Intensity (type IV) sheeting. Cost analysis, including labor, maintenance, and material cost components of the three retroreflective sheeting materials, showed that High Intensity (type IV) could increase sign visibility and legibility at night for Departments of Transportation with limited budgets, consequently increasing driver safety on roadways. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Allocating physicians' overhead costs to services: an econometric/accounting-activity based-approach.

    PubMed

    Peden, Al; Baker, Judith J

    2002-01-01

    Using the optimizing properties of econometric analysis, this study analyzes how physician overhead costs (OC) can be allocated to multiple activities to maximize precision in reimbursing the costs of services. Drawing on work by Leibenstein and Friedman, the analysis also shows that allocating OC to multiple activities unbiased by revenue requires controlling for revenue when making the estimates. Further econometric analysis shows that it is possible to save about 10 percent of OC by paying only for those that are necessary.

  10. Characterization results for the October 2015-Tank for farm 3H evaporator overhead examples

    SciTech Connect

    Nicholson, J. C.

    2016-01-28

    This report contains the radioanalytical results of the 3H evaporator overhead sample received at SRNL on October 13, 2015. Specifically, concentrations of 137Cs, 90Sr, and 129I are reported and compared to the corresponding Waste Acceptance Criteria (WAC) limits of the Effluent Treatment Project (ETP) Waste Water Collection Tank (WWCT) (rev. 6). All of the radionuclide concentrations in the sample were found to be in compliance with the ETP WAC limits.

  11. The relation between maternal phenotype and offspring size, explained by overhead material costs of reproduction.

    PubMed

    Filin, Ido

    2015-01-07

    Variation in offspring size with female size and other aspects of the maternal phenotype is commonly observed and taxonomically widespread. However, life history theory predicts that optimal offspring size should not depend on maternal size or total reproductive effort. This incongruity persists despite various modifications to theory, that nonetheless, either are limited in their applicability or fail to alter the prediction of fixed offspring size. I demonstrate that the persistence of this theoretical outcome stems from an ideal assumption that reproductive effort relates only to direct material costs, and therefore, equal or proportional to clutch mass or the product of offspring size and number. A major innovation in my study is to explicitly distinguish between direct and overhead components of the costs of reproduction. When overhead energetic costs of reproduction are explicitly incorporated, I readily obtain variation in optimal offspring size with maternal phenotype. This consequence of overhead costs of reproduction has not been demonstrated before. I identify functional forms of such overhead costs that facilitate variation in optimal offspring size. In particular, costs that are more sensitive to offspring size than to offspring number are most effective in causing variation in offspring size. The novelty of the model lies in succeeding to resolve the above incongruity both within the framework of traditional models of optimal offspring size and within more dynamic description of the lifecycle (addressing simultaneously both offspring and maternal performance), including stochastic effects, difference between reserves and structural components of size, and distinction between starvation and extrinsic mortality. My predictions explain several patterns of variation in size and body composition of offspring, with respect to both environmental conditions and maternal phenotype. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Characterization Results for the March 2016 H-Tank Farm 2H Evaporator Overhead Samples

    SciTech Connect

    Nicholson, J. C.

    2016-05-09

    This report contains the radioanalytical results of the 2H evaporator overhead sample received at SRNL on March 16, 2016. Specifically, concentrations of 137Cs, 90Sr, and 129I are reported and compared to the corresponding Waste Acceptance Criteria (WAC) limits of the Effluent Treatment Project (ETP) Waste Water Collection Tank (WWCT) (rev. 6). All of the radionuclide concentrations in the sample were found to be in compliance with the ETP WAC limits.

  13. STS-30 aft flight deck onboard view of overhead window, Earth limb, cow photo

    NASA Technical Reports Server (NTRS)

    1989-01-01

    Since the beginning of manned space travel, astronauts have taken onboard with them items of person sentiment. During STS-30 onboard Atlantis, Orbiter Vehicle (OV) 104, Mission Specialist Mark C. Lee brought along a photograph of a cow. The photo testifies to his background as one reared on a Wisconsin farm and is displayed on aft flight deck alongside an overhead window. Outside the window, some 160 nautical miles away, is the cloud-covered Earth surface.

  14. Characterization Results For The 2013 HTF 3H Evaporator Overhead Samples

    SciTech Connect

    Washington, A. L. II

    2013-12-04

    This report tabulates the radiochemical analysis of the 3H evaporator overhead sample for {sup 137}Cs, {sup 90}Sr, and {sup 129}I to meet the requirements in the Effluent Treatment Project (ETP) Waste Acceptance Criteria (WAC) (rev. 6). This report identifies the sample receipt date, preparation method, and analysis performed in the accumulation of the listed values. All data was found to be within the ETP WAC (rev. 6) specification for the Waste Water Collection Tanks (WWCT).

  15. GAMMA FACILITY, TRA611, INTERIOR. WITH HELP OF OVERHEAD CHAIN AND ...

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

    GAMMA FACILITY, TRA-611, INTERIOR. WITH HELP OF OVERHEAD CHAIN AND HOOK, SCIENTIST GUIDES METAL CONTAINER (HOLDING POTATOES, IN THIS CASE) INTO RECEIVING "COLUMN" IN THE GAMMA CANAL. NOTE OTHER COLUMNS AT RIGHT AND LEFT WALLS OF CANAL. NEAR BOTTOM OF CANAL, SPENT MTR FUEL WILL IRRADIATE POTATOES. INL NEGATIVE NO. 56-439. R.G. Larsen, Photographer, 2/8/1956 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  16. Estimation of the maximal voltage induced on an overhead line due to the nearby lightning

    SciTech Connect

    Jankov, V.

    1997-01-01

    Determination of the maximal voltages induced on the overhead power lines by nearby lightning stroke is a complex problem. The scope of this paper is to recognize the parameters that affect the maximal voltages and to present an equation for their estimation. This equation gives an opportunity to calculate the maximal voltage with the reasonable accuracy avoiding complex electromagnetic field calculus. It may be very useful in the estimation of flashover and outage rates due to the nearby strokes.

  17. CDR Cockrell, PLT Polansky, and MS Ivins peer through AFD overhead windows

    NASA Image and Video Library

    2001-02-07

    STS098-335-0028 (7-20 February 2001) --- From the aft flight deck of the Space Shuttle Atlantis, astronaut Marsha S. Ivins, STS-98 mission specialist, looks through an overhead window toward her space walking colleagues, who exposed this 35mm frame. Also visible in the window are astronauts Kenneth D. Cockrell and Mark L. Polansky, commander and pilot for the STS-98/5a mission.

  18. The effects of overhead transparency design on retention, recall, and application of data analysis content.

    PubMed

    Van Hoozer, H; Brink, P J; Oppliger, R

    1989-04-01

    This experimental study tested the effects of overhead transparency design in conjunction with live lecture on retention, recall, and application of data analysis content over three occasions using a Solomon Four-Group, pretest-posttest design. Pretested subjects showed significant (p less than .001) gains in test scores from pre to posttest. No significant differences were found in pretest scores between control and experimental treatment groups or among the posttest scores of either the experimental or control groups.

  19. Scapular bracing and alteration of posture and muscle activity in overhead athletes with poor posture.

    PubMed

    Cole, Ashley K; McGrath, Melanie L; Harrington, Shana E; Padua, Darin A; Rucinski, Terri J; Prentice, William E

    2013-01-01

    Overhead athletes commonly have poor posture. Commercial braces are used to improve posture and function, but few researchers have examined the effects of shoulder or scapular bracing on posture and scapular muscle activity. To examine whether a scapular stabilization brace acutely alters posture and scapular muscle activity in healthy overhead athletes with forward-head, rounded-shoulder posture (FHRSP). Randomized controlled clinical trial. Applied biomechanics laboratory. Thirty-eight healthy overhead athletes with FHRSP. Participants were assigned randomly to 2 groups: compression shirt with no strap tension (S) and compression shirt with the straps fully tensioned (S + T). Posture was measured using lateral-view photography with retroreflective markers. Electromyography (EMG) of the upper trapezius (UT), middle trapezius (MT), lower trapezius (LT), and serratus anterior (SA) in the dominant upper extremity was measured during 4 exercises (scapular punches, W's, Y's, T's) and 2 glenohumeral motions (forward flexion, shoulder extension). Posture and exercise EMG measurements were taken with and without the brace applied. Head and shoulder angles were measured from lateral-view digital photographs. Normalized surface EMG was used to assess mean muscle activation of the UT, MT, LT, and SA. Application of the brace decreased forward shoulder angle in the S + T condition. Brace application also caused a small increase in LT EMG during forward flexion and Y's and a small decrease in UT and MT EMG during shoulder extension. Brace application in the S + T group decreased UT EMG during W's, whereas UT EMG increased during W's in the S group. Application of the scapular brace improved shoulder posture and scapular muscle activity, but EMG changes were highly variable. Use of a scapular brace might improve shoulder posture and muscle activity in overhead athletes with poor posture.

  20. A Formula for Use in Unabsorbed Overhead Claims in Government Contracts.

    DTIC Science & Technology

    1986-09-01

    31868 Contract 2 Direct Labor $ 7360 Overhead @ 178.57% 13143 Subtotal $20503 Profit--10% 2050 Total $22553 Replacement Work Direct Labor $ 360...Work Days (@ $40 per day) 9 days 1Average Replacement Work Direct Labor $ 24 (for the 15 day delay period) Average Direct Labor--Delay Period $ 88...Replacement Work Days (@ $40 per day) 9 days Average Replacement Work Direct Labor $ 24 (for the 15 day delay period) U Average Direct Labor--Delay Period $ 88

  1. STS-30 aft flight deck onboard view of overhead window, Earth limb, cow photo

    NASA Technical Reports Server (NTRS)

    1989-01-01

    Since the beginning of manned space travel, astronauts have taken onboard with them items of person sentiment. During STS-30 onboard Atlantis, Orbiter Vehicle (OV) 104, Mission Specialist Mark C. Lee brought along a photograph of a cow. The photo testifies to his background as one reared on a Wisconsin farm and is displayed on aft flight deck alongside an overhead window. Outside the window, some 160 nautical miles away, is the cloud-covered Earth surface.

  2. Optical Jitter Effects on Target Detection and Tracking of Overhead Persistent Infrared Systems

    DTIC Science & Technology

    2015-12-01

    demonstrated the jitter blur’s effects on spatial resolution and intensity, which significantly decreased the system’s ability to detect and track ... EFFECTS ON TARGET DETECTION AND TRACKING OF OVERHEAD PERSISTENT INFRARED SYSTEMS by Christopher R. Flores December 2015 Thesis Advisor...December 2015 3. REPORT TYPE AND DATES COVERED Master’s thesis 4. TITLE AND SUBTITLE OPTICAL JITTER EFFECTS ON TARGET DETECTION AND TRACKING OF

  3. Exercise prescription for overhead athletes with shoulder pathology: a systematic review with best evidence synthesis.

    PubMed

    Wright, Alexis A; Hegedus, Eric J; Tarara, Daniel T; Ray, Samantha C; Dischiavi, Steven L

    2017-04-12

    To produce a best evidence synthesis of exercise prescription used when treating shoulder pathology in the overhead athlete. A systematic review of exercises used in overhead athletes including case studies and clinical commentaries. MEDLINE, PubMed, SPORTDiscus and CINAHL from database inception through July 8, 2016. We examined data from randomised controlled trials and prospective cohort (level I-IV evidence) studies that addressed exercise intervention in the rehabilitation of the overhead athlete with shoulder pathology. Case studies and clinical commentaries (level V evidence) were examined to account for expert opinion-based research. Data were combined using best evidence synthesis and graded (A-F) recommendations (Centre for Evidence-Based Medicine). There were 33 unique exercises in six level I-IV studies that met our inclusion criteria. Most exercises were single-plane, upper extremity exercises performed below 90(o) of elevation. There were 102 unique exercises in 33 level V studies that met our inclusion criteria. These exercises emphasised plyometrics, kinetic chain and sport-specific training. Overall, evidence for exercise interventions in overhead athletes with shoulder pathology is dominated by expert opinion (grade D). There is great variability between exercise approaches suggested by experts and those investigated in research studies and the overall level of evidence is low. The strongest available evidence (level B) supports the use of single-plane, open chain upper extremity exercises performed below 90° of elevation and closed chain upper extremity exercises. Clinical expert pieces support a more advanced, global treatment approach consistent with the complex, multidimensional nature of sport. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  4. Scapular Bracing and Alteration of Posture and Muscle Activity in Overhead Athletes With Poor Posture

    PubMed Central

    Cole, Ashley K; McGrath, Melanie L; Harrington, Shana E; Padua, Darin A; Rucinski, Terri J; Prentice, William E

    2013-01-01

    Context Overhead athletes commonly have poor posture. Commercial braces are used to improve posture and function, but few researchers have examined the effects of shoulder or scapular bracing on posture and scapular muscle activity. Objective To examine whether a scapular stabilization brace acutely alters posture and scapular muscle activity in healthy overhead athletes with forward-head, rounded-shoulder posture (FHRSP). Design Randomized controlled clinical trial. Setting Applied biomechanics laboratory. Patients or Other Participants Thirty-eight healthy overhead athletes with FHRSP. Intervention(s) Participants were assigned randomly to 2 groups: compression shirt with no strap tension (S) and compression shirt with the straps fully tensioned (S + T). Posture was measured using lateral-view photography with retroreflective markers. Electromyography (EMG) of the upper trapezius (UT), middle trapezius (MT), lower trapezius (LT), and serratus anterior (SA) in the dominant upper extremity was measured during 4 exercises (scapular punches, W's, Y's, T's) and 2 glenohumeral motions (forward flexion, shoulder extension). Posture and exercise EMG measurements were taken with and without the brace applied. Main Outcome Measure(s) Head and shoulder angles were measured from lateral-view digital photographs. Normalized surface EMG was used to assess mean muscle activation of the UT, MT, LT, and SA. Results Application of the brace decreased forward shoulder angle in the S + T condition. Brace application also caused a small increase in LT EMG during forward flexion and Y's and a small decrease in UT and MT EMG during shoulder extension. Brace application in the S + T group decreased UT EMG during W's, whereas UT EMG increased during W's in the S group. Conclusions Application of the scapular brace improved shoulder posture and scapular muscle activity, but EMG changes were highly variable. Use of a scapular brace might improve shoulder posture and muscle activity in

  5. High power thyristors with 5 kV blocking voltage. Volume 1: Development of high-voltage-thyristors (4.5 kV) with good dynamic properties

    NASA Technical Reports Server (NTRS)

    Lock, K.; Patalong, H.; Platzoeder, K.

    1979-01-01

    Using neutron irradiated silicon with considerably lower spread in resistivity as compared to conventionally doped silicon it was possible to produce power thyristors with breakdown voltages between 3.5 kV and 5.5 kV. The thyristor pellets have a diameter of 50 mm. Maximum average on-state currents of 600 to 800 A can be reached with these elements. The dynamic properties of the thryistors could be improved to allow standard applications up to maximum repetitive voltages of 4.5 kV.

  6. Comparison of the NIST and NPL Air Kerma Standards Used for X-Ray Measurements Between 10 kV and 80 kV.

    PubMed

    O'Brien, M; Lamperti, P; Williams, T; Sander, T

    2000-01-01

    A direct comparison was made between the air kerma primary standards used for the measurements of low-energy x rays at the National Institute of Standards and Technology (NIST) and the National Physical Laboratory (NPL). The comparison was conducted at the NPL using NPL reference radiation qualities between 10 kV and 80 kV. The results show the primary air-kerma standards to agree within 0.6 % of their values for beam qualities up to 80 kV.

  7. A Novel Transient Fault Current Sensor Based on the PCB Rogowski Coil for Overhead Transmission Lines.

    PubMed

    Liu, Yadong; Xie, Xiaolei; Hu, Yue; Qian, Yong; Sheng, Gehao; Jiang, Xiuchen

    2016-05-21

    The accurate detection of high-frequency transient fault currents in overhead transmission lines is the basis of malfunction detection and diagnosis. This paper proposes a novel differential winding printed circuit board (PCB) Rogowski coil for the detection of transient fault currents in overhead transmission lines. The interference mechanism of the sensor surrounding the overhead transmission line is analyzed and the guideline for the interference elimination is obtained, and then a differential winding printed circuit board (PCB) Rogowski coil is proposed, where the branch and return line of the PCB coil were designed to be strictly symmetrical by using a joining structure of two semi-rings and collinear twisted pair differential windings in each semi-ring. A serial test is conducted, including the frequency response, linearity, and anti-interference performance as well as a comparison with commercial sensors. Results show that a PCB Rogowski coil has good linearity and resistance to various external magnetic field interferences, thus enabling it to be widely applied in fault-current-collecting devices.

  8. The Quantitative Overhead Analysis for Effective Task Migration in Biosensor Networks

    PubMed Central

    Kim, Tae-Kyung; Eom, Jung-Ho; Chung, Tai-Myoung

    2013-01-01

    We present a quantitative overhead analysis for effective task migration in biosensor networks. A biosensor network is the key technology which can automatically provide accurate and specific parameters of a human in real time. Biosensor nodes are typically very small devices, so the use of computing resources is restricted. Due to the limitation of nodes, the biosensor network is vulnerable to an external attack against a system for exhausting system availability. Since biosensor nodes generally deal with sensitive and privacy data, their malfunction can bring unexpected damage to system. Therefore, we have to use a task migration process to avoid the malfunction of particular biosensor nodes. Also, it is essential to accurately analyze overhead to apply a proper migration process. In this paper, we calculated task processing time of nodes to analyze system overhead and compared the task processing time applied to a migration process and a general method. We focused on a cluster ratio and different processing time between biosensor nodes in our simulation environment. The results of performance evaluation show that task execution time is greatly influenced by a cluster ratio and different processing time of biosensor nodes. In the results, the proposed algorithm reduces total task execution time in a migration process. PMID:24187668

  9. Comparison of charged nanoparticle concentrations near busy roads and overhead high-voltage power lines.

    PubMed

    Jayaratne, E R; Ling, X; Morawska, L

    2015-09-01

    Overhead high-voltage power lines are known sources of corona ions. These ions rapidly attach to aerosols to form charged particles in the environment. Although the effect of ions and charged particles on human health is largely unknown, much attention has focused on the increasing exposure as a result of the expanding power network in urban residential areas. However, it is not widely known that a large number of charged particles in urban environments originate from motor vehicle emissions. In this study, for the first time, we compare the concentrations of charged nanoparticles near busy roads and overhead power lines. We show that large concentrations of both positive and negative charged nanoparticles are present near busy roadways and that these concentrations commonly exceed those under high-voltage power lines. We estimate that the concentration of charged nanoparticles found near two freeways carrying around 120 vehicles per minute exceeded the corresponding maximum concentrations under two corona-emitting overhead power lines by as much as a factor of 5. The difference was most pronounced when a significant fraction of traffic consisted of heavy-duty diesel vehicles which typically have high particle and charge emission rates. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. A Novel Transient Fault Current Sensor Based on the PCB Rogowski Coil for Overhead Transmission Lines

    PubMed Central

    Liu, Yadong; Xie, Xiaolei; Hu, Yue; Qian, Yong; Sheng, Gehao; Jiang, Xiuchen

    2016-01-01

    The accurate detection of high-frequency transient fault currents in overhead transmission lines is the basis of malfunction detection and diagnosis. This paper proposes a novel differential winding printed circuit board (PCB) Rogowski coil for the detection of transient fault currents in overhead transmission lines. The interference mechanism of the sensor surrounding the overhead transmission line is analyzed and the guideline for the interference elimination is obtained, and then a differential winding printed circuit board (PCB) Rogowski coil is proposed, where the branch and return line of the PCB coil were designed to be strictly symmetrical by using a joining structure of two semi-rings and collinear twisted pair differential windings in each semi-ring. A serial test is conducted, including the frequency response, linearity, and anti-interference performance as well as a comparison with commercial sensors. Results show that a PCB Rogowski coil has good linearity and resistance to various external magnetic field interferences, thus enabling it to be widely applied in fault-current-collecting devices. PMID:27213402

  11. [Analysis of the shoulder joint mobility in overhead sports before and after experimental treatment].

    PubMed

    Kaćanski, Ivana; Gava, Branka Protić; Soldatović, Srdan

    2011-01-01

    "Overhead" sports, characterized by predominant movements of the hands above the head, are associated with very dynamic, often acyclic movements and require strong muscles of humero-scapular regions with high mobility of the shoulder joint as well as flexibility and ability to relax these muscles. This study was aimed at analyzing the shoulder joint mobility before and after conducting kinesiology treatment for a period of 6 months. The research included two complex exercises. The study included 100 "overhead" sports male athletes, who were randomly divided into the experimental and control group, aged 14 to 18 years. The range of motion was measured in degrees by goniometer. We calculated the central and depression parameter. There was a statistically significant difference inflexion, extension, abduction, adduction, external and internal rotation at the final measure in favor of the experimental group at the level of significance p<0.001, and some positive effects of the applied exercises were observed. Kinesitherapy had positive effects on the elasticity of the connective tissue capsule, ligaments and tendons. Changes in the shoulder area f the "overhead" sports athletes can be reduced to the same extent and at the same time by stretching and strength exercises. The authors of this paper have given their modest contribution by suggesting a more appropriate planning of training and performance of players at training and matches. This paper tries to emphasize the importance of proper incorporation of the corrective exercises in training.

  12. Uptake and Accumulation of Pharmaceuticals in Lettuce Under Surface and Overhead Irrigations

    NASA Astrophysics Data System (ADS)

    Bhalsod, G.; Chuang, Y. H.; Jeon, S.; Gui, W.; Li, H.; Guber, A.; Zhang, W.

    2015-12-01

    Pharmaceuticals and personal care products are being widely detected in wastewater and surface waters. As fresh water becomes scarcer, interests in using reclaimed water for crop irrigation is intensified. Since reclaimed waters often carry trace levels of pharmaceuticals, accumulation of pharmaceuticals in food crops could increase the risk of human exposure. This study aims to investigate uptake and accumulations of pharmaceuticals in greenhouse-grown lettuce under contrasting irrigation practices (i.e., overhead and surface irrigations). Lettuce was irrigated with water spiked with 11 commonly used pharmaceuticals (acetaminophen, caffeine, carbamazepine, sulfadiazine, sulfamethoxazole, carbadox, trimethoprim, lincomycin hydrochloride, oxytetracycline hydrochloride, monensin sodium, and tylosin). Weekly sampling of lettuce roots, shoots, and soils were continued for 5 weeks, and the samples were freeze dried, extracted for pharmaceuticals and analyzed by LC-MS/MS. Preliminary results indicate that higher concentrations of pharmaceuticals were found in overhead irrigated lettuce compared to surface irrigated lettuce. For carbamezapine, sulfadiazine, trimethoprim, oxytetracycline, and monensin sodium, their concentrations generally increased in lettuce shoots in the overhead treatment over time. However, acetaminophen was found at higher concentrations in both shoots and roots, indicating that acetaminophen can be easily transported in the plant system. This study provides insight on developing better strategies for using reclaimed water for crop irrigations, while minimizing the potential risks of pharmaceutical contamination of vegetables.

  13. Corona performance of a compact 230-kV line

    SciTech Connect

    Chartier, V.L.; Blair, D.E.; Easley, M.D.; Raczkowski, R.T.

    1995-01-01

    Permitting requirements and the acquisition of new rights-of-way for transmission facilities has in recent years become increasingly difficult for most utilities, including Puget Sound Power and Light Company. In order to maintain a high degree of reliability of service while being responsive to public concerns regarding the siting of high voltage (HV) transmission facilities, Puget Power has found it necessary to more heavily rely upon the use of compact lines in franchise corridors. Compaction does, however, precipitate increased levels of audible noise (AN) and radio and TV interference (RI and TVI) due to corona on the conductors and insulator assemblies. Puget Power relies upon the Bonneville Power Administration (BPA) Corona and Field Effects computer program to calculate AN and RI for new lines. Since there was some question of the program`s ability to accurately represent quiet 230-kV compact designs, a joint project was undertaken with BPA to verify the program`s algorithms. Long-term measurements made on an operating Puget Power 230-kV compact line confirmed the accuracy of BPA`s AN model; however, the RI measurements were much lower than predicted by the BPA and other programs. This paper also describes how the BPA computer program can be used to calculate the voltage needed to expose insulator assemblies to the correct electric field in single test setups in HV laboratories.

  14. Corona performance of a compact 230-kV line

    SciTech Connect

    Chartier, V.L.; Blair, D.E.; Easley, M.D.; Raczkowski, R.T.

    1994-12-31

    Permitting requirements and the acquisition of new rights-of-way for transmission facilities has in recent years become increasingly difficult for most utilities, including Puget Sound Power and Light Company. In order to maintain a high degree of reliability of service while being responsive to public concerns regarding the siting of high voltage (HV) transmission facilities, Puget Power has found it necessary to more heavily rely upon the use of compact lines in franchise corridors. Compaction does, however, precipitant increased levels of audible noise (AN) and radio and TV interference (RI and TVI) due to corona on the conductors and insulator assemblies. Puget Power relies upon the Bonneville Power Administration (BPA) Corona and Field Effects computer program to calculate AN and RI for new lines. Since there was some question of the program`s ability to accurately represent quiet 230-kV compact designs, a joint project was undertaken with BPA to verify the program`s algorithms. Long-term measurements made on an operating Puget Power 230-kV compact line confirmed the accuracy of BPA`s AN model; however, the RI measurements were much lower than predicted by the BPA computer and other programs. This paper also describes how the BPA computer program can be used to calculate the voltage needed to expose insulator assemblies to the correct electric field in single test setups in HV laboratories.

  15. Wild Horse 69-kV transmission line environmental assessment

    SciTech Connect

    1996-12-01

    Hill County Electric Cooperative Inc. (Hill County) proposes to construct and operate a 69-kV transmission line from its North Gildford Substation in Montana north to the Canadian border. A vicinity project area map is enclosed as a figure. TransCanada Power Corporation (TCP), a Canadian power-marketing company, will own and construct the connecting 69-kV line from the international border to Express Pipeline`s pump station at Wild Horse, Alberta. This Environmental Assessment is prepared for the Department of Energy (DOE) as lead federal agency to comply with the requirements of the National Environmental Policy Act (NEPA), as part of DOE`s review and approval process of the applications filed by Hill County for a DOE Presidential Permit and License to Export Electricity to a foreign country. The purpose of the proposed line is to supply electric energy to a crude oil pump station in Canada, owned by Express Pipeline Ltd. (Express). The pipeline would transport Canadian-produced oil from Hardisty, Alberta, Canada, to Caster, Wyoming. The Express Pipeline is scheduled to be constructed in 1996--97 and will supply crude oil to refineries in Wyoming and the midwest.

  16. Stichodactyla helianthus peptide, a pharmacological tool for studying Kv3.2 channels.

    PubMed

    Yan, Lizhen; Herrington, James; Goldberg, Ethan; Dulski, Paula M; Bugianesi, Randal M; Slaughter, Robert S; Banerjee, Priya; Brochu, Richard M; Priest, Birgit T; Kaczorowski, Gregory J; Rudy, Bernardo; Garcia, Maria L

    2005-05-01

    Voltage-gated potassium (Kv) channels regulate many physiological functions and represent important therapeutic targets in the treatment of several clinical disorders. Although some of these channels have been well-characterized, the study of others, such as Kv3 channels, has been hindered because of limited pharmacological tools. The current study was initiated to identify potent blockers of the Kv3.2 channel. Chinese hamster ovary (CHO)-K1 cells stably expressing human Kv3.2b (CHO-K1.hKv3.2b) were established and characterized. Stichodactyla helianthus peptide (ShK), isolated from S. helianthus venom and a known high-affinity blocker of Kv1.1 and Kv1.3 channels, was found to potently inhibit 86Rb+ efflux from CHO-K1.hKv3.2b (IC50 approximately 0.6 nM). In electrophysiological recordings of Kv3.2b channels expressed in Xenopus laevis oocytes or in planar patch-clamp studies, ShK inhibited hKv3.2b channels with IC50 values of approximately 0.3 and 6 nM, respectively. Despite the presence of Kv3.2 protein in human pancreatic beta cells, ShK has no effect on the Kv current of these cells, suggesting that it is unlikely that homotetrameric Kv3.2 channels contribute significantly to the delayed rectifier current of insulin-secreting cells. In mouse cortical GABAergic fast-spiking interneurons, however, application of ShK produced effects consistent with the blockade of Kv3 channels (i.e., an increase in action potential half-width, a decrease in the amplitude of the action potential after hyperpolarization, and a decrease in maximal firing frequency in response to depolarizing current injections). Taken together, these results indicate that ShK is a potent inhibitor of Kv3.2 channels and may serve as a useful pharmacological probe for studying these channels in native preparations.

  17. Kv3 voltage-gated potassium channels regulate neurotransmitter release from mouse motor nerve terminals.

    PubMed

    Brooke, Ruth E; Moores, Thomas S; Morris, Neil P; Parson, Simon H; Deuchars, Jim

    2004-12-01

    Voltage-gated potassium (Kv) channels are critical to regulation of neurotransmitter release throughout the nervous system but the roles and identity of the subtypes involved remain unclear. Here we show that Kv3 channels regulate transmitter release at the mouse neuromuscular junction (NMJ). Light- and electron-microscopic immunohistochemistry revealed Kv3.3 and Kv3.4 subunits within all motor nerve terminals of muscles examined [transversus abdominus, lumbrical and flexor digitorum brevis (FDB)]. To determine the roles of these Kv3 subunits, intracellular recordings were made of end-plate potentials (EPPs) in FDB muscle fibres evoked by electrical stimulation of tibial nerve. Tetraethylammonium (TEA) applied at low concentrations (0.05-0.5 mM), which blocks only a few known potassium channels including Kv3 channels, did not affect muscle fibre resting potential but significantly increased the amplitude of all EPPs tested. Significantly, this effect of TEA was still observed in the presence of the large-conductance calcium-activated potassium channel blockers iberiotoxin (25-150 nM) and Penitrem A (100 nM), suggesting a selective action on Kv3 subunits. Consistent with this, 15-microM 4-aminopyridine, which blocks Kv3 but not large-conductance calcium-activated potassium channels, enhanced evoked EPP amplitude. Unexpectedly, blood-depressing substance-I, a toxin selective for Kv3.4 subunits, had no effect at 0.05-1 microM. The combined presynaptic localization of Kv3 subunits and pharmacological enhancement of EPP amplitude indicate that Kv3 channels regulate neurotransmitter release from presynaptic terminals at the NMJ.

  18. Sites and Functional Consequence of Alkylphenol Anesthetic Binding to Kv1.2 Channels.

    PubMed

    Bu, Weiming; Liang, Qiansheng; Zhi, Lianteng; Maciunas, Lina; Loll, Patrick J; Eckenhoff, Roderic G; Covarrubias, Manuel

    2017-02-15

    Inhalational general anesthetics, such as sevoflurane and isoflurane, modulate a subset of brain Kv1 potassium channels. However, the Kv1.2 channel is resistant to propofol, a commonly used intravenous alkylphenol anesthetic. We hypothesize that propofol binds to a presumed pocket involving the channel's S4-S5 linker, but functional transduction is poor and, therefore, propofol efficacy is low. To test this hypothesis, we used a photoactive propofol analog (meta-aziPropofol = AziPm) to directly probe binding and electrophysiological and mutational analyses in Xenopus oocytes to probe function. We find that AziPm photolabels L321 in the S4-S5 linker of both the wild-type Kv1.2 and a mutant Kv1.2 (G329 T) with a novel gating phenotype. Furthermore, whereas propofol does not significantly modulate Kv1.2 WT but robustly potentiates Kv1.2 G329T, AziPm inhibits Kv1.2 WT and also potentiates Kv1.2 G329T. Kv1.2 modulation by AziPm was abolished by two mutations that decreased hydrophobicity at L321 (L321A and L321F), confirming the specific significance of the S4-S5 linker in the mechanism of general anesthetic modulation. Since AziPm binds to Kv1.2 G329T and shares the propofol ability to potentiate this mutant, the parent propofol likely also binds to the Kv1.2 channel. However, binding and alkylphenol-induced transduction are seemingly sensitive to the conformation of the S4-S5 linker site (altered by G329T) and subtle differences in the chemical structures of propofol and AziPm. Overall, the results are consistent with a mechanism of general anesthetic modulation that depends on the complementarity of necessary ligand binding and permissive ion channel conformations that dictate modulation and efficacy.

  19. Kv4 potassium channels modulate hippocampal EPSP-spike potentiation and spatial memory in rats.

    PubMed

    Truchet, Bruno; Manrique, Christine; Sreng, Leam; Chaillan, Franck A; Roman, François S; Mourre, Christiane

    2012-06-14

    Kv4 channels regulate the backpropagation of action potentials (b-AP) and have been implicated in the modulation of long-term potentiation (LTP). Here we showed that blockade of Kv4 channels by the scorpion toxin AmmTX3 impaired reference memory in a radial maze task. In vivo, AmmTX3 intracerebroventricular (i.c.v.) infusion increased and stabilized the EPSP-spike (E-S) component of LTP in the dentate gyrus (DG), with no effect on basal transmission or short-term plasticity. This increase in E-S potentiation duration could result from the combination of an increase in excitability of DG granular cells with a reduction of GABAergic inhibition, leading to a strong reduction of input specificity. Radioactive in situ hybridization (ISH) was used to evaluate the amounts of Kv4.2 and Kv4.3 mRNA in brain structures at different stages of a spatial learning task in naive, pseudoconditioned, and conditioned rats. Significant differences in Kv4.2 and Kv4.3 mRNA levels were observed between conditioned and pseudoconditioned rats. Kv4.2 and Kv4.3 mRNA levels were transiently up-regulated in the striatum, nucleus accumbens, retrosplenial, and cingulate cortices during early stages of learning, suggesting an involvement in the switch from egocentric to allocentric strategies. Spatial learning performance was positively correlated with the levels of Kv4.2 and Kv4.3 mRNAs in several of these brain structures. Altogether our findings suggest that Kv4 channels could increase the signal-to-noise ratio during information acquisition, thereby allowing a better encoding of the memory trace.

  20. Synthesis of psoralen derivatives and their blocking effect of hKv1.5 channel.

    PubMed

    Eun, Jae Soon; Kim, Kwang Sik; Kim, Han Na; Park, Seon Ah; Ma, Tian-Ze; Lee, Kyung A; Kim, Dae Keun; Kim, Hyung Kyo; Kim, In Su; Jung, Young Hoon; Zee, Ok Pyo; Yoo, Dong Jin; Kwak, Yong Geun

    2007-02-01

    Previously, we found that a furocoumarin derivative, psoralen (7H-furo[3,2-g][1]benzopyran-7-one), blocked a human Kv1.5 potassium channel (hKv1.5) and has a potential antiarrhythmic effect. In the present study, to develop more potent hKv1.5 blockers or antiarrhythmic drugs, we synthesized ten psoralen derivatives and examined their blocking effects on hKv1.5 stably expressed in Ltk cells. Among the newly synthesized psoralen derivatives, three derivatives (Compounds 5, 9 and 10) showed the open channel-blocking effect. Compound 9 among them was the most potent in blocking hKv1.5. We found that compound 9, one of the psoralen derivatives, inhibited the hKv1.5 current in a concentration-, use- and voltage-dependent manner with an IC50 value of 27.4 +/- 5.1 nM at +60 mV. Compound 9 accelerated the inactivation kinetics of the hKv1.5 channel, slowed the deactivation kinetics of hKv1.5 current resulting in a tail crossover phenomenon. Compound 9 inhibited hKv1.5 current in a use-dependent manner. These results indicate that compound 9, one of psoralen derivatives, acts on hKv1.5 channel as an open channel blocker and is much more potent than psoralen in blocking hKv1.5 channel. If further studies were done, compound 9 might be an ideal antiarrhythmic drug for atrial fibrillation.

  1. Clinical and radiological outcomes of type 2 superior labral anterior posterior repairs in elite overhead athletes.

    PubMed

    Park, Jin-Young; Chung, Seok-Won; Jeon, Seung-Hyub; Lee, Jun-Gyu; Oh, Kyung-Soo

    2013-06-01

    Although there are multiple reports on surgical outcomes of type 2 superior labral anterior posterior (SLAP) repairs, a literature review noted a paucity of data on clinical and radiological outcomes in elite overhead athletes. To determine midterm clinical outcomes of type 2 SLAP repairs in elite overhead athletes and whether labral integrity provides consistent return to play. Case series; Level of evidence, 4. Medical records were retrospectively reviewed of 24 elite overhead athletes who underwent arthroscopic type 2 SLAP repairs. There were 18 men and 6 women, and their mean age was 22.7 years (range, 19-30 years); the majority of them (16/24) were baseball players. Four outcome measures were used: visual analog scale (VAS) for pain and satisfaction, American Shoulder and Elbow Surgeons (ASES) score, subjective feeling of recovery, and return to play. Multidetector computed tomographic arthrography was performed to evaluate labral integrity after surgery. At a mean follow-up of 45.8 months (range, 24-68 months), overall pain and function improved significantly. The VAS for pain was 5.7 preoperatively and 2.0 postoperatively (P < .01), and VAS for satisfaction was 8.6. The ASES score was 55.8 preoperatively and 87.1 postoperatively (P < .01). The overall mean value of subjective feeling of recovery was approximately 76%. Twelve of 24 athletes (50%) returned to play after the operation. Although there was a trend toward higher return rate in the other overhead athletes (75%) compared with the baseball players (38%), this trend did not reach statistical significance (P = .097). Labral retear with clinical significance was noted in 2 athletes who failed to return to play. Osteolysis was observed in 2 athletes, 1 of whom had a retear. A statistical relation between the integrity of the repair and return to play was not found (P > .05). Arthroscopic SLAP repairs show favorable clinical and radiological outcomes; however, the study findings raise a concern that

  2. Acromiohumeral Distance and 3-Dimensional Scapular Position Change After Overhead Muscle Fatigue

    PubMed Central

    Maenhout, Annelies; Dhooge, Famke; Van Herzeele, Maarten; Palmans, Tanneke; Cools, Ann

    2015-01-01

    Context: Muscle fatigue due to repetitive and prolonged overhead sports activity is considered an important factor contributing to impingement-related rotator cuff pathologic conditions in overhead athletes. The evidence on scapular and glenohumeral kinematic changes after fatigue is contradicting and prohibits conclusions about how shoulder muscle fatigue affects acromiohumeral distance. Objective: To investigate the effect of a fatigue protocol resembling overhead sports activity on acromiohumeral distance and 3-dimensional scapular position in overhead athletes. Design: Cross-sectional study. Setting: Institutional laboratory. Patients or Other Participants: A total of 29 healthy recreational overhead athletes (14 men, 15 women; age = 22.23 ± 2.82 years, height = 178.3 ± 7.8 cm, mass = 71.6 ± 9.5 kg). Intervention(s) The athletes were tested before and after a shoulder muscle-fatiguing protocol. Main Outcome Measure(s) Acromiohumeral distance was measured using ultrasound, and scapular position was determined with an electromagnetic motion-tracking system. Both measurements were performed at 3 elevation positions (0°, 45°, and 60° of abduction). We used a 3-factor mixed model for data analysis. Results: After fatigue, the acromiohumeral distance increased when the upper extremity was actively positioned at 45° (Δ = 0.78 ± 0.24 mm, P = .002) or 60° (Δ = 0.58 ± 0.23 mm, P = .02) of abduction. Scapular position changed after fatigue to a more externally rotated position at 45° (Δ = 4.97° ± 1.13°, P < .001) and 60° (Δ = 4.61° ± 1.90°, P = .001) of abduction, a more upwardly rotated position at 45° (Δ = 6.10° ± 1.30°, P < .001) and 60° (Δ = 7.20° ± 1.65°, P < .001) of abduction, and a more posteriorly tilted position at 0°, 45°, and 60° of abduction (Δ = 1.98° ± 0.41°, P < .001). Conclusions: After a fatiguing protocol, we found changes in acromiohumeral distance and scapular position that corresponded with an impingement

  3. A computer program to perform dynamic thermal analysis for bare overhead conductors during short-time overload conditions

    SciTech Connect

    Shrestha, P.; Pham, K.

    1995-12-31

    Under emergency conditions, a bare overhead conductor can carry an increased amount of current that is well in excess of its normal rating. When there is this increase in current flow on a bare overhead conductor, the temperature does not rise instantaneously. but increases along a curve determined by the current, the conductor properties and the ambient conditions. The conductor temperature at the end of a short-time overload period must be restricted to its maximum design value. This paper presents a simplified approach in analyzing the dynamic performance for bare overhead conductors during short-time overload condition. A computer program was developed to calculate the short-time ratings for bare overhead conductors. The following parameters: current induced heating. solar load, convective/conductive cooling, radiative cooling, altitude, wind velocity and ampacity of the bare conductor were considered. Several sample graphical output lots are included with the paper.

  4. Dynamic Stiffness of a Railway Overhead Wire System and its Effect on Pantograph-Catenary System Dynamics

    NASA Astrophysics Data System (ADS)

    Wu, T. X.; Brennan, M. J.

    1999-01-01

    For an electrical railway overhead wire system there are two main factors which crucially affect the quality of current collection. One is the spatial stiffness variation of the overhead wire along each span and the other is the flexural wave motion in the wire. In this paper a periodically excited single-degree-of-freedom (SDOF) model of a combined pantograph-catenary system is introduced and its basic dynamic behaviour is discussed. To investigate the effect of wave propagation in the overhead wire on vibration of the pantograph the dynamic stiffness of the catenary is introduced into the model. The dynamic stiffness of the catenary is determined by representing the overhead wire system as an infinite periodically spring-supported string. The results show that the dynamic stiffness of the catenary varies with train speed and its effect on the performance of the pantograph-catenary system is discussed.

  5. Dynamic Stiffness of a Railway Overhead Wire System and its Effect on PANTOGRAPH-CATENARY System Dynamics

    NASA Astrophysics Data System (ADS)

    Wu, T. X.; Brennan, M. J.

    1999-01-01

    For an electrical railway overhead wire system there are two main factors which crucially affect the quality of current collection. One is the spatial stiffness variation of the overhead wire along each span and the other is the flexural wave motion in the wire. In this paper a periodically excited single-degree-of-freedom (SDOF) model of a combined pantograph-catenary system is introduced and its basic dynamic behaviour is discussed. To investigate the effect of wave propagation in the overhead wire on vibration of the pantograph the dynamic stiffness of the catenary is introduced into the model. The dynamic stiffness of the catenary is determined by representing the overhead wire system as an infinite periodically spring-supported string. The results show that the dynamic stiffness of the catenary varies with train speed and its effect on the performance of the pantograph-catenary system is discussed.

  6. An assessment of GafChromic film for measuring 50 kV and 100 kV percentage depth dose curves.

    PubMed

    Fletcher, Claire Lesley; Mills, John A

    2008-06-07

    Percentage depth dose (PDD) curves were obtained for 50 kV and 100 kV x-rays on a Gulmay Medical D3000 DXR unit. Different dosimetry systems were compared including a Scanditronix Wellhofer small volume cylindrical ion chamber, a Wellhofer photon PFD diode, a PTW soft x-ray parallel plate chamber (N23342) and two types of radiochromic film: GafChromic EBT and GafChromic MD55. The PDD curves were also compared to BEAMnrc Monte Carlo predictions. GafChromic film was found to be a valid choice of dosimeter for measuring percentage depth dose curves at 100 kV and 50 kV. All the dosimeters showed agreement with predictions at depths greater than 10 mm, while near the surface GafChromic film and PFD diodes give the best agreement to Monte Carlo values.

  7. Current Concepts in the Evaluation and Treatment of the Shoulder in Overhead-Throwing Athletes, Part 1

    PubMed Central

    Reinold, Michael M.; Gill, Thomas J.

    2010-01-01

    The overhead-throwing athlete is a challenging sports medicine patient. The repetitive microtraumatic stresses imposed on the athlete’s shoulder joint complex during the throwing motion constantly places the athlete at risk for injury. These stresses may effect several adaptations to normal shoulder range of motion, strength, and scapula position. The clinician should therefore appreciate the unique physical characteristics of the overhead-throwing athlete to accurately evaluate and treat throwing-related injuries. PMID:23015922

  8. U.S. Army Corps of Engineers: Building Overhead Costs into Projects and Customers’ Views on Information Provided

    DTIC Science & Technology

    2013-06-01

    contact Anne-Marie Fennell at (202) 512-3841 or fennella@gao.gov. Page i GAO-13-528 Army Corps Overhead Process Letter 1...listed in appendix III. Sincerely yours, Anne-Marie Fennell Director, Natural Resources and Environment Agency Comments and Our Evaluation...Acknowledgments Page 31 GAO-13-528 Army Corps Overhead Process Anne-Marie Fennell , (202) 512-3841 or fennella@gao.gov In addition to the

  9. Kv4.3 is not required for the generation of functional Ito,f channels in adult mouse ventricles

    PubMed Central

    Niwa, Noriko; Wang, Wei; Sha, Qun; Marionneau, Céline; Nerbonne, Jeanne M.

    2008-01-01

    Accumulated evidence suggests that the heteromeric assembly of Kv4.2 and Kv4.3 α subunits underlies the fast transient Kv current (Ito,f) in rodent ventricles. Recent studies, however, demonstrated that the targeted deletion of Kv4.2 results in the complete elimination of Ito,f in adult mouse ventricles, revealing an essential role for the Kv4.2 α subunit in the generation of mouse ventricular Ito,f channels. The present study was undertaken to investigate directly the functional role of Kv4.3 by examining the effects of the targeted disruption of the KCND3 (Kv4.3) locus. Mice lacking Kv4.3 (Kv4.3−/−) appear indistinguishable from wild type control animals, and no structural or functional abnormalities were evident in Kv4.3−/− hearts. Voltage-clamp recordings revealed that functional Ito,f channels are expressed in Kv4.3−/− ventricular myocytes, and that mean Ito,f densities are similar to those recorded from wild type cells. In addition, Ito,f properties (inactivation rates, voltage-dependences of inactivation and rates of recovery from inactivation) in Kv4.3−/− and wild type mouse ventricular myocytes were indistinguishable. Quantitative RT-PCR and Western blot analyses did not reveal any measurable changes in the expression of Kv4.2 or the Kv channel interacting protein (KChIP2) in Kv4.3−/−ventricles. Taken together, the results presented here suggest that, in contrast with Kv4.2, Kv4.3 is not required for the generation of functional mouse ventricular Ito,f channels. PMID:18045613

  10. Brain expression of Kv3 subunits during development, adulthood and aging and in a murine model of Alzheimer's disease.

    PubMed

    Boda, Enrica; Hoxha, Eriola; Pini, Alessandro; Montarolo, Francesca; Tempia, Filippo

    2012-03-01

    In neurons, voltage-dependent Kv3 potassium channels are essential for the generation of action potentials at high frequency. A dysregulation of the Kv3.1 and Kv3.4 channel subunits has been suggested to contribute to neuronal and glial alterations in Alzheimer's disease, but a quantitative evaluation of these subunits in a mouse model of the pathology is still lacking. We analysed the profile of expression of the four Kv3 subunits by quantitative reverse transcription PCR and Western blot in the whole mouse brain and in dissected brain regions (olfactory bulb, septum, neocortex, hippocampus, brainstem and cerebellum) from 14 days after conception to 18 months after birth. In addition, we measured the levels of Kv3.1 and Kv3.4 messenger RNAs (mRNAs) and proteins in neocortex and hippocampus of APPPS1 mice, a transgenic model of Alzheimer's disease. Although all Kv3 transcripts were significantly expressed in embryonic age in whole brain extracts, only Kv3.1, Kv3.2 and Kv3.4 subunit proteins were present, suggesting a novel role for Kv3 channels at this developmental stage. With the exception of Kv3.4, during postnatal development, Kv3 transcripts and proteins showed a progressive increase in expression and reached an asymptote in adulthood, suggesting that the increase in Kv3 expression during development might contribute to the maturation of the electrical activity of neurons. During aging, Kv3 expression was rather stable. In contrast, in the neocortex of aged APPPS1 mice, Kv3.1 mRNA and protein levels were significantly lower compared to wild type, suggesting that a decrease in Kv3 currents could play a role in the cognitive symptoms of Alzheimer's disease.

  11. Deletion of the Kv2.1 delayed rectifier potassium channel leads to neuronal and behavioral hyperexcitability

    PubMed Central

    Speca, David J.; Ogata, Genki; Mandikian, Danielle; Bishop, Hannah I.; Wiler, Steve W.; Eum, Kenneth; Wenzel, H. Jürgen; Doisy, Emily T.; Matt, Lucas; Campi, Katharine L.; Golub, Mari S.; Nerbonne, Jeanne M.; Hell, Johannes W.; Trainor, Brian C.; Sack, Jon T.; Schwartzkroin, Philip A.; Trimmer, James S.

    2014-01-01

    The Kv2.1 delayed rectifier potassium channel exhibits high-level expression in both principal and inhibitory neurons throughout the central nervous system, including prominent expression in hippocampal neurons. Studies of in vitro preparations suggest that Kv2.1 is a key yet conditional regulator of intrinsic neuronal excitability, mediated by changes in Kv2.1 expression, localization and function via activity-dependent regulation of Kv2.1 phosphorylation. Here we identify neurological and behavioral deficits in mutant (Kv2.1−/−) mice lacking this channel. Kv2.1−/− mice have grossly normal characteristics. No impairment in vision or motor coordination was apparent, although Kv2.1−/− mice exhibit reduced body weight. The anatomic structure and expression of related Kv channels in the brains of Kv2.1−/− mice appears unchanged. Delayed rectifier potassium current is diminished in hippocampal neurons cultured from Kv2.1−/− animals. Field recordings from hippocampal slices of Kv2.1−/− mice reveal hyperexcitability in response to the convulsant bicuculline, and epileptiform activity in response to stimulation. In Kv2.1−/− mice, long-term potentiation at the Schaffer collateral – CA1 synapse is decreased. Kv2.1−/− mice are strikingly hyperactive, and exhibit defects in spatial learning, failing to improve performance in a Morris Water Maze task. Kv2.1−/− mice are hypersensitive to the effects of the convulsants flurothyl and pilocarpine, consistent with a role for Kv2.1 as a conditional suppressor of neuronal activity. Although not prone to spontaneous seizures, Kv2.1−/− mice exhibit accelerated seizure progression. Together, these findings suggest homeostatic suppression of elevated neuronal activity by Kv2.1 plays a central role in regulating neuronal network function. PMID:24494598

  12. VizieR Online Data Catalog: KV Vel and TW Crv JHK light curves (Ribeiro+, 2011)

    NASA Astrophysics Data System (ADS)

    Ribeiro, T.; Baptista, R.

    2010-11-01

    Near-infrared time resolved photometric observations of KV Vel and TW Crv. KV Vel was observed quasi-simultaneously in JHK bands while TW Crv was observed on the H and K bands. Table contains the flux calibrated photometric measurements for each object on each band and consists of phase, flux and flux error. (1 data file).

  13. The Link between Ion Permeation and Inactivation Gating of Kv4 Potassium Channels

    PubMed Central

    Shahidullah, Mohammad; Covarrubias, Manuel

    2003-01-01

    Kv4 potassium channels undergo rapid inactivation but do not seem to exhibit the classical N-type and C-type mechanisms present in other Kv channels. We have previously hypothesized that Kv4 channels preferentially inactivate from the preopen closed state, which involves regions of the channel that contribute to the internal vestibule of the pore. To further test this hypothesis, we have examined the effects of permeant ions on gating of three Kv4 channels (Kv4.1, Kv4.2, and Kv4.3) expressed in Xenopus oocytes. Rb+ is an excellent tool for this purpose because its prolonged residency time in the pore delays K+ channel closing. The data showed that, only when Rb+ carried the current, both channel closing and the development of macroscopic inactivation are slowed (1.5- to 4-fold, relative to the K+ current). Furthermore, macroscopic Rb+ currents were larger than K+ currents (1.2- to 3-fold) as the result of a more stable open state, which increases the maximum open probability. These results demonstrate that pore occupancy can influence inactivation gating in a manner that depends on how channel closing impacts inactivation from the preopen closed state. By examining possible changes in ionic selectivity and the influence of elevating the external K+ concentration, additional experiments did not support the presence of C-type inactivation in Kv4 channels. PMID:12547775

  14. Context view of RyantoRainbow 100kv Transmission Line showing copper wire ...

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

    Context view of Ryan-to-Rainbow 100kv Transmission Line showing copper wire conductors leaving roof of Ryan Powerhouse. View to east - Ryan Hydroelectric Facility, Ryan-to-Rainbow 100 kV Transmission Line, West bank of Missouri River, northeast of Great Falls, Great Falls, Cascade County, MT

  15. AMIGO-Kv2.1 Potassium Channel Complex Is Associated With Schizophrenia-Related Phenotypes

    PubMed Central

    Peltola, Marjaana A.; Kuja-Panula, Juha; Liuhanen, Johanna; Võikar, Vootele; Piepponen, Petteri; Hiekkalinna, Tero; Taira, Tomi; Lauri, Sari E.; Suvisaari, Jaana; Kulesskaya, Natalia; Paunio, Tiina; Rauvala, Heikki

    2016-01-01

    The enormous variability in electrical properties of neurons is largely affected by a multitude of potassium channel subunits. Kv2.1 is a widely expressed voltage-dependent potassium channel and an important regulator of neuronal excitability. The Kv2.1 auxiliary subunit AMIGO constitutes an integral part of the Kv2.1 channel complex in brain and regulates the activity of the channel. AMIGO and Kv2.1 localize to the distinct somatodendritic clusters at the neuronal plasma membrane. Here we have created and characterized a mouse line lacking the AMIGO gene. Absence of AMIGO clearly reduced the amount of the Kv2.1 channel protein in mouse brain and altered the electrophysiological properties of neurons. These changes were accompanied by behavioral and pharmacological abnormalities reminiscent of those identified in schizophrenia. Concomitantly, we have detected an association of a rare, population-specific polymorphism of KV2.1 (KCNB1) with human schizophrenia in a genetic isolate enriched with schizophrenia. Our study demonstrates the involvement of AMIGO-Kv2.1 channel complex in schizophrenia-related behavioral domains in mice and identifies KV2.1 (KCNB1) as a strong susceptibility gene for schizophrenia spectrum disorders in humans. PMID:26240432

  16. Potentiation of the Kv1 family K+ channel by cortisone analogs

    PubMed Central

    Pan, Yaping; Levin, Elena J.; Quick, Matthias; Zhou, Ming

    2013-01-01

    The Kv1 family voltage-dependent K+ channels are essential for termination of action potentials in neurons and myocytes. These channels form a stable complex with their beta subunits (Kvβ), some of which inhibit channel activity. Cortisone potentiates Kv1 channel by binding to Kvβ and promoting its dissociation from the channel, but its half-maximum effective concentration is ~46 μM. To identify corticosteroids that are more efficient than cortisone, we examined 25 cortisone analogs and found that fluticasone propionate potentiates channel current with a half-maximum effective concentration (EC50) of 37 ± 1.1 nM. Further studies showed that fluticasone propionate potentiates channel current by inducing dissociation of Kvβ, and docking of fluticasone propionate into the cortisone binding site reveals potential interactions that enhance the EC50 value. Thus, fluticasone propionate provides a starting point for rational design of more efficient small-molecule compounds that increase Kv1 activity and affect the integrity of the Kv1-Kvβ complex. PMID:22803826

  17. Potentiation of the Kv1 family K(+) channel by cortisone analogues.

    PubMed

    Pan, Yaping; Levin, Elena J; Quick, Matthias; Zhou, Ming

    2012-10-19

    The Kv1 family voltage-dependent K(+) channels are essential for termination of action potentials in neurons and myocytes. These channels form a stable complex with their beta subunits (Kvβ), some of which inhibit channel activity. Cortisone potentiates Kv1 channel by binding to Kvβ and promoting its dissociation from the channel, but its half-maximum effective concentration is ∼46 μM. To identify corticosteroids that are more efficient than cortisone, we examined 25 cortisone analogues and found that fluticasone propionate potentiates channel current with a half-maximum effective concentration (EC(50)) of 37 ± 1.1 nM. Further studies showed that fluticasone propionate potentiates channel current by inducing dissociation of Kvβ, and docking of fluticasone propionate into the cortisone binding site reveals potential interactions that enhance the EC(50) value. Thus, fluticasone propionate provides a starting point for rational design of more efficient small-molecule compounds that increase Kv1 activity and affect the integrity of the Kv1-Kvβ complex.

  18. Anti-voltage-gated potassium channel Kv1.4 antibodies in myasthenia gravis.

    PubMed

    Romi, Fredrik; Suzuki, Shigeaki; Suzuki, Norihiro; Petzold, Axel; Plant, Gordon T; Gilhus, Nils Erik

    2012-07-01

    Myasthenia gravis (MG) is an autoimmune disease characterized by skeletal muscle weakness mainly caused by acetylcholine receptor antibodies. MG can be divided into generalized and ocular, and into early-onset (<50 years of age) and late-onset (≥50 years of age). Anti-Kv1.4 antibodies targeting α-subunits (Kv1.4) of the voltage-gated potassium K(+) channel occurs frequently among patients with severe MG, accounting for 18% of a Japanese MG population. The aim of this study was to characterize the clinical features and serological associations of anti-Kv1.4 antibodies in a Caucasian MG population with mild and localized MG. Serum samples from 129 Caucasian MG patients with mainly ocular symptoms were tested for the presence of anti-Kv1.4 antibodies and compared to clinical and serological parameters. There were 22 (17%) anti-Kv1.4 antibody-positive patients, most of them women with late-onset MG, and all of them with mild MG. This contrasts to the Japanese anti-Kv1.4 antibody-positive patients who suffered from severe MG with bulbar symptoms, myasthenic crisis, thymoma, myocarditis and prolonged QT time on electrocardiography, despite equal anti-Kv1.4 antibody occurrence in both populations. No other clinical or serological parameters influenced anti-Kv1.4 antibody occurrence.

  19. Kv4 Potassium Channels Modulate Hippocampal EPSP-Spike Potentiation and Spatial Memory in Rats

    ERIC Educational Resources Information Center

    Truchet, Bruno; Manrique, Christine; Sreng, Leam; Chaillan, Franck A.; Roman, Francois S.; Mourre, Christiane

    2012-01-01

    Kv4 channels regulate the backpropagation of action potentials (b-AP) and have been implicated in the modulation of long-term potentiation (LTP). Here we showed that blockade of Kv4 channels by the scorpion toxin AmmTX3 impaired reference memory in a radial maze task. In vivo, AmmTX3 intracerebroventricular (i.c.v.) infusion increased and…

  20. The beneficial effect of blocking Kv1.3 in the psoriasiform SCID mouse model.

    PubMed

    Gilhar, Amos; Bergman, Reuven; Assay, Bedia; Ullmann, Yehuda; Etzioni, Amos

    2011-01-01

    The Kv1.3 channel is important in the activation and function of effector memory T cells. Recently, specific blockers of the Kv1.3 channel have been developed as a potential therapeutic option for diverse autoimmune diseases. In psoriatic lesions, most lymphocytes are memory effector T cells. The aim of the present study was to detect the expression of Kv1.3 channels in these cells in psoriatic lesions as well as in human psoriasiform skin grafts using the severe combined immunodeficient (SCID) mouse model. Histological and immunohistochemical staining for Kv1.3 expression and various inflammatory markers was performed in sections obtained from six psoriatic patients and 18 beige-SCID mice with psoriasiform human skin grafts. Six grafted mice were treated with Stichodactyla helianthus neurotoxin (ShK), a known Kv1.3 blocker. The results showed an increased number of Kv1.3+ cells in the psoriatic skin as well as in the psoriasiform skin grafts as compared with normal skin and normal skin grafts. Injections of ShK showed a marked therapeutic effect in three of six psoriasiform skin grafts. A significantly decreased number of Kv1.3+ cells was observed in the responders compared with the control grafts. This pilot study, although performed in a small number of mice, reveals the possible beneficial effect of Kv1.3 blockers in psoriasis patients.