Experimental Studies on Grooved Double Pipe Heat Exchanger with Different Groove Space

Science.gov (United States)

Sunu, P. W.; Arsawan, I. M.; Anakottapary, D. S.; Santosa, I. D. M. C.; Yasa, I. K. A.

2018-01-01

Experimental studies were performed on grooved double pipe heat exchanger (DPHE) with different groove space. The objective of this work is to determine optimal heat transfer parameter especially logarithmic mean temperature difference (LMTD). The document in this paper also provides the total heat observed by the cold fluid. The rectangular grooves were incised on outer surface of tube side with circumferential pattern and two different grooves space, namely 1 mm and 2 mm. The distance between grooves and the grooves high were kept constant, 8 mm and 0.3 mm respectively. The tube diameter is 20 mm and its made of aluminium. The shell is made of acrylic which has 28 mm in diameter. Water is used as the working fluid. Using counter flow scheme, the cold fluid flows in the annulus room of DPHE. The volume flowrate of hot fluid remains constant at 15 lpm. The volume flowrate of cold fluid were varied from 11 lpm to 15 lpm. Based on logarithmic mean temperature difference analysis, the LMTD of 1 mm grooves space was higher compared to that of 2 mm grooves space. The smaller grooves space has more advantage since the recirculating region are increased which essentially cause larger heat transfer enhancement.

PROBABILISTIC MODEL FOR AIRPORT RUNWAY SAFETY AREAS

Directory of Open Access Journals (Sweden)

Stanislav SZABO

2017-06-01

Full Text Available The Laboratory of Aviation Safety and Security at CTU in Prague has recently started a project aimed at runway protection zones. The probability of exceeding by a certain distance from the runway in common incident/accident scenarios (take-off/landing overrun/veer-off, landing undershoot is being identified relative to the runway for any airport. As a result, the size and position of safety areas around runways are defined for the chosen probability. The basis for probability calculation is a probabilistic model using statistics from more than 1400 real-world cases where jet airplanes have been involved over the last few decades. Other scientific studies have contributed to understanding the issue and supported the model’s application to different conditions.

Current status of Joint FAA/NASA Runway Friction Program

Science.gov (United States)

Yager, Thomas J.; Vogler, William A.

1989-01-01

Tests with specially instrumented NASA B-737 and FAA B-727 aircraft together with several different ground friction measuring devices have been conducted for a variety of runway surface types and wetness conditions. This effort is part of the Joint FAA/NASA Aircraft Ground Vehicle Runway Friction Program aimed at obaining a better understanding of aircraft ground handling performance under adverse weather conditions and defining relationships between aircraft and ground vehicle tire friction measurements. Aircraft braking performance on dry, wet, snow-, and ice-covered runway conditions is discussed together with ground vehicle friction data obtained under similar runway conditions. For the wet, compacted snow- and ice-covered runway conditions, the relationship between ground vehicles and aircraft friction data is identified. The influence of major test parameters on friction measurements such as speed, test tire characteristics, and surface contaminant type are discussed. The test results indicate that use of properly maintained and calibrated ground vehicles for monitoring runway friction conditions should be encouraged particularly under adverse weather conditions. The current status of the runway friction program is summarized and future test plans are identified.

Performance optimization of grooved slippers for aero hydraulic pumps

Directory of Open Access Journals (Sweden)

Juan Chen

2016-06-01

Full Text Available A computational fluid dynamics (CFD simulation method based on 3-D Navier–Stokes equation and Arbitrary Lagrangian–Eulerian (ALE method is presented to analyze the grooved slipper performance of piston pump. The moving domain of grooved slipper is transformed into a fixed reference domain by the ALE method, which makes it convenient to take the effects of rotate speed, body force, temperature, and oil viscosity into account. A geometric model to express the complex structure, which covers the orifice of piston and slipper, vented groove and the oil film, is constructed. Corresponding to different oil film thicknesses calculated in light of hydrostatic equilibrium theory and boundary conditions, a set of simulations is conducted in COMSOL to analyze the pump characteristics and effects of geometry (groove width and radius, orifice size on these characteristics. Furthermore, the mechanics and hydraulics analyses are employed to validate the CFD model, and there is an excellent agreement between simulation and analytical results. The simulation results show that the sealing land radius, orifice size and groove width all dramatically affect the slipper behavior, and an optimum tradeoff among these factors is conducive to optimizing the pump design.

Differential diagnosis of groove pancreatic carcinomas vs. groove pancreatitis: Usefulness of the portal venous phase

International Nuclear Information System (INIS)

Ishigami, Kousei; Tajima, Tsuyoshi; Nishie, Akihiro; Kakihara, Daisuke; Fujita, Nobuhiro; Asayama, Yoshiki; Ushijima, Yasuhiro; Irie, Hiroyuki; Nakamura, Masafumi; Takahata, Shunichi; Ito, Tetsuhide; Honda, Hiroshi

2010-01-01

Purpose: To clarify if the portal venous phase is helpful for the differential diagnosis of groove pancreatic carcinomas and groove pancreatitis. Materials and methods: MDCT and MRI of groove pancreatic carcinomas (n = 7) and groove pancreatitis (n = 15) were retrospectively reviewed by two radiologists independently. The signal intensity on T2-weighted images was subjectively assessed. The presence or absence of common bile duct (CBD) and main pancreatic duct (MPD) strictures, calcifications, and cystic lesions was evaluated. Additionally, the appearance of groove pancreatic carcinoma and that of groove pancreatitis in the portal venous phase on dynamic MDCT and MRI were compared. Results: There were no significant differences in the signal intensity on T2-weighted images and in the presence or absence of CBD and MPD strictures, calcifications, and cystic lesions between groove pancreatic carcinomas and groove pancreatitis. However, patchy focal enhancement in the portal venous phase was more commonly observed in groove pancreatitis than groove pancreatic carcinoma (Reviewers 1 and 2: 14/15 [93.3%] vs. 1/7 [14.3%], P < 0.0001). In addition, peripheral enhancement was only seen in groove pancreatic carcinomas (Reviewer 1: 4/7 [57.1%] vs. 0/15 [0%], P < 0.005, and Reviewer 2: 3/7 [42.9%] vs. 0/15 [0%], P < 0.05). Conclusion: The portal venous phase may be helpful for the differential diagnosis of groove pancreatic carcinomas and groove pancreatitis.

Economic utilization of general aviation airport runways

Science.gov (United States)

Piper, R. R.

1971-01-01

The urban general aviation airport economics is studied in detail. The demand for airport services is discussed, and the different types of users are identified. The direct cost characteristics of the airport are summarized; costs to the airport owner are largely fixed, and, except at certain large airports, weight is not a significant factor in airport costs. The efficient use of an existing airport facility is explored, with the focus on the social cost of runway congestion as traffic density at the airport build up and queues form. The tradeoff between aircraft operating costs and airport costs is analyzed in terms of runway length. The transition from theory to practice is treated, and the policy of charging prices only on aircraft storage and fuel is felt likely to continue. Implications of the study from the standpoint of public policy include pricing that spreads traffic peaks to improve runway utilization, and pricing that discriminates against aircraft requiring long runways and causes owners to adopt V/STOL equipment.

Final Environmental Assessment for the Runway Extension and New Parking Apron at Tyndall Air Force Base, Florida

National Research Council Canada - National Science Library

2004-01-01

The Air Force prepared an Environmental Assessment (EA) of the potential environmental consequences of constructing a new heavy parking apron and runway extension at Tyndall Air Force Base (AFB), Florida...

System-Oriented Runway Management Concept of Operations

Science.gov (United States)

Lohr, Gary W.; Atkins, Stephen

2015-01-01

This document describes a concept for runway management that maximizes the overall efficiency of arrival and departure operations at an airport or group of airports. Specifically, by planning airport runway configurations/usage, it focuses on the efficiency with which arrival flights reach their parking gates from their arrival fixes and departure flights exit the terminal airspace from their parking gates. In the future, the concept could be expanded to include the management of other limited airport resources. While most easily described in the context of a single airport, the concept applies equally well to a group of airports that comprise a metroplex (i.e., airports in close proximity that share resources such that operations at the airports are at least partially dependent) by including the coordination of runway usage decisions between the airports. In fact, the potential benefit of the concept is expected to be larger in future metroplex environments due to the increasing need to coordinate the operations at proximate airports to more efficiently share limited airspace resources. This concept, called System-Oriented Runway Management (SORM), is further broken down into a set of airport traffic management functions that share the principle that operational performance must be measured over the complete surface and airborne trajectories of the airport's arrivals and departures. The "system-oriented" term derives from the belief that the traffic management objective must consider the efficiency of operations over a wide range of aircraft movements and National Airspace System (NAS) dynamics. The SORM concept is comprised of three primary elements: strategic airport capacity planning, airport configuration management, and combined arrival/departure runway planning. Some aspects of the SORM concept, such as using airport configuration management1 as a mechanism for improving aircraft efficiency, are novel. Other elements (e.g., runway scheduling, which is a part

Grooved cold moderator tests

International Nuclear Information System (INIS)

Inoue, K.; Kiyanagi, Y.; Iwasa, H.; Watanabe, N.; Ikeda, S.; Carpenter, J.M.; Ishikawa, Y.

1983-01-01

We performed some grooved cold moderator experiments for methane at 20 K by using the Hokkaido University linac to obtain information to be used in the planning of the KENS-I' project. Cold neutron gains, spatial distribution of emitted beams and time distribution of the neutrons in the grooved cold moderator were measured. Furthermore, we assessed the effects of the grooved cold moderator on the performances of the spectrometers presently installed at the KENS-I cold source. We concluded that the grooved cold moderator benefited appreciably the performances of the spectrometers

NASA tire/runway friction projects

Science.gov (United States)

Yager, Thomas J.

1995-01-01

The paper reviews several aspects of NASA Langley Research Center's tire/runway friction evaluations directed towards improving the safety and economy of aircraft ground operations. The facilities and test equipment used in implementing different aircraft tire friction studies and other related aircraft ground performance investigations are described together with recent workshop activities at NASA Wallops Flight Facility. An overview of the pending Joint NASA/Transport Canada/FM Winter Runway Friction Program is given. Other NASA ongoing studies and on-site field tests are discussed including tire wear performance and new surface treatments. The paper concludes with a description of future research plans.

Capacity Analysis for Parallel Runway through Agent-Based Simulation

Directory of Open Access Journals (Sweden)

Yang Peng

2013-01-01

Full Text Available Parallel runway is the mainstream structure of China hub airport, runway is often the bottleneck of an airport, and the evaluation of its capacity is of great importance to airport management. This study outlines a model, multiagent architecture, implementation approach, and software prototype of a simulation system for evaluating runway capacity. Agent Unified Modeling Language (AUML is applied to illustrate the inbound and departing procedure of planes and design the agent-based model. The model is evaluated experimentally, and the quality is studied in comparison with models, created by SIMMOD and Arena. The results seem to be highly efficient, so the method can be applied to parallel runway capacity evaluation and the model propose favorable flexibility and extensibility.

Aircraft and ground vehicle friction measurements obtained under winter runway conditions

Science.gov (United States)

Yager, Thomas J.

1989-01-01

Tests with specially instrumented NASA B-737 and B-727 aircraft together with several different ground friction measuring devices have been conducted for a variety of runway surface types and wetness conditions. This effort is part of the Joint FAA/NASA Aircraft/Ground Vehicle Runway Friction Program aimed at obtaining a better understanding of aircraft ground handling performance under adverse weather conditions, and defining relationships between aircraft and ground vehicle tire friction measurements. Aircraft braking performance on dry, wet, snow-, and ice-covered runway conditions is discussed together with ground vehicle friction data obtained under similar runway conditions. For the wet, compacted snow- and ice-covered runway conditions, the relationship between ground vehicles and aircraft friction data is identified. The influence of major test parameters on friction measurements such as speed, test tire characteristics, and surface contaminant-type are discussed. The test results indicate that use of properly maintained and calibrated ground vehicles for monitoring runway friction conditions should be encouraged particularly under adverse weather conditions.

Shuttle landing runway modification to improve tire spin-up wear performance

Science.gov (United States)

Daugherty, Robert H.; Yager, Thomas J.; Stubbs, Sandy M.

1988-01-01

This paper presents the results of a series of tire spin-up wear tests on a simulated Kennedy Space Center (KSC) runway that were carried out to investigate the tire wear problem for Space Shuttle landings on the KSC runway and to test several modifications of the runway surface designed to alleviate the problem. It was found that the runway surface produced by a concrete smoothing machine using cutters spaced one and three-quarters blades per centimeter provided adequate wet cornering while limiting spin-up wear. Based on the test results, the KSC runway was smoothed for about 1066 m at each end, leaving the original high friction surface, for better wet steering and braking, in the 2438-m central section.

Optics of multiple grooves in metal

DEFF Research Database (Denmark)

Skjølstrup, Enok Johannes Haahr; Søndergaard, Thomas; Pedersen, Kjeld

2017-01-01

This paper theoretically studies how the optics of multiple grooves in a metal change as the number of grooves gradually increased from a single groove to infinitely many arranged in a periodic array. In the case of a single groove, the out-of-plane scattering (OUP) cross section at resonance can...

Optics of multiple grooves in metal

DEFF Research Database (Denmark)

Skjølstrup, Enok Johannes Haahr; Søndergaard, Thomas; Pedersen, Kjeld

2017-01-01

This paper studies theoretically how the optics of multiple grooves in a metal change as the number of grooves is increased gradually from a single groove to innitely many arranged in a periodic array. In the case of a single groove the out-of-plane scattering (OUP) cross section at resonance can...

Local-scale stratigraphy of grooved terrain on Ganymede

Science.gov (United States)

Murchie, Scott L.; Head, James W.; Helfenstein, Paul; Plescia, Jeffrey B.

1987-01-01

The surface of the Jovian satellite, Ganymede, is divided into two main units, dark terrain cut by arcuate and subradial furrows, and light terrain consisting largely of areas with pervasive U-shaped grooves. The grooved terrain may be subdivided on the basis of pervasive morphology of groove domains into four terrain types: (1) elongate bands of parallel grooves (groove lanes); (2) polygonal domains of parallel grooves (grooved polygons); (3) polygonal domains of two orthogonal groove sets (reticulate terrain); and (4) polygons having two to several complexly cross-cutting groove sets (complex grooved terrain). Reticulate terrain is frequently dark and not extensively resurfaced, and grades to a more hummocky terrain type. The other three grooved terrain types have almost universally been resurfaced by light material during their emplacement. The sequence of events during grooved terrain emplacement has been investigated. An attempt is made to integrate observed geologic and tectonic patterns to better constrain the relative ages and styles of emplacement of grooved terrain types. A revised model of grooved terrain emplacement is proposed and is tested using detailed geologic mapping and measurement of crater density.

Endosonography of groove pancreatitis

NARCIS (Netherlands)

Tio, T. L.; Luiken, G. J.; Tytgat, G. N.

1991-01-01

Groove pancreatitis is a rare form of chronic pancreatitis. Distinction between pancreatitis and pancreatic carcinoma is often difficult. Two cases of groove pancreatitis diagnosed by endosonography are described. A hypoechoic pattern between the duodenal wall and pancreas was clearly imaged in both

Optics of multiple ultrasharp grooves in metal

DEFF Research Database (Denmark)

Skjølstrup, Enok Johannes Haahr; Søndergaard, Thomas

2017-01-01

. When the multiple-groove array is illuminated by a plane wave the out-of-plane scattering is found to be extraordinarily large compared with the expected maximum from a geometric-optics estimate even for array widths of many wavelengths. The out-of-plane scattering is even higher per groove compared......The optics of multiple ultrasharp sub-wavelength grooves in metal is studied theoretically. Focus is on the transition from a single groove, where the scattering cross section is significant and can exceed the groove width, to infinitely many grooves in a periodic array with very low reflectance...

Development and Execution of the RUNSAFE Runway Safety Bayesian Belief Network Model

Science.gov (United States)

Green, Lawrence L.

2015-01-01

One focus area of the National Aeronautics and Space Administration (NASA) is to improve aviation safety. Runway safety is one such thrust of investigation and research. The two primary components of this runway safety research are in runway incursion (RI) and runway excursion (RE) events. These are adverse ground-based aviation incidents that endanger crew, passengers, aircraft and perhaps other nearby people or property. A runway incursion is the incorrect presence of an aircraft, vehicle or person on the protected area of a surface designated for the landing and take-off of aircraft; one class of RI events simultaneously involves two aircraft, such as one aircraft incorrectly landing on a runway while another aircraft is taking off from the same runway. A runway excursion is an incident involving only a single aircraft defined as a veer-off or overrun off the runway surface. Within the scope of this effort at NASA Langley Research Center (LaRC), generic RI, RE and combined (RI plus RE, or RUNSAFE) event models have each been developed and implemented as a Bayesian Belief Network (BBN). Descriptions of runway safety issues from the literature searches have been used to develop the BBN models. Numerous considerations surrounding the process of developing the event models have been documented in this report. The event models were then thoroughly reviewed by a Subject Matter Expert (SME) panel through multiple knowledge elicitation sessions. Numerous improvements to the model structure (definitions, node names, node states and the connecting link topology) were made by the SME panel. Sample executions of the final RUNSAFE model have been presented herein for baseline and worst-case scenarios. Finally, a parameter sensitivity analysis for a given scenario was performed to show the risk drivers. The NASA and LaRC research in runway safety event modeling through the use of BBN technology is important for several reasons. These include: 1) providing a means to clearly

Runway Safety: It's Everybody's Business. We Want You to Put the Brakes on Runway Incursions

National Research Council Canada - National Science Library

Cardosi, Kim

2001-01-01

This booklet tell pilots and controllers what they can do to help prevent runway incursions by helping them to avoid situations that induce errors and alerting them to them to situations as extra vigilance is required...

Dielectric image line groove antennas for millimeterwaves

Science.gov (United States)

Solbach, K.; Wolff, I.

Grooves in the ground plane of dielectric image lines are proposed as a new radiating structure. A figure is included showing the proposed groove structure as a discontinuity in a dielectric image line. A wave incident on the dielectric image line is partly reflected by the discontinuity, partly transmitted across the groove, and partly radiated into space above the line. In a travelling-wave antenna, a number of grooves are arranged below a dielectric guide, with spacings around one guide wavelength to produce a beam in the upper half space. A prescribed aperture distribution can be effected by tapering the series radiation resistance of the grooves. This can be done by adjusting the depths of the grooves with a constant width or by varying the widths of the grooves with a constant depth. Attention is also given to circular grooves. Here, the widths of the holes are chosen so that they can be considered as waveguides operating far below the cut-off frequency of the fundamental circular waveguide mode.

Benefits Assessment for Single-Airport Tactical Runway Configuration Management Tool (TRCM)

Science.gov (United States)

Oseguera-Lohr, Rosa; Phojanamonogkolkij, Nipa; Lohr, Gary W.

2015-01-01

The System-Oriented Runway Management (SORM) concept was developed as part of the Airspace Systems Program (ASP) Concepts and Technology Development (CTD) Project, and is composed of two basic capabilities: Runway Configuration Management (RCM), and Combined Arrival/Departure Runway Scheduling (CADRS). RCM is the process of designating active runways, monitoring the active runway configuration for suitability given existing factors, and predicting future configuration changes; CADRS is the process of distributing arrivals and departures across active runways based on local airport and National Airspace System (NAS) goals. The central component in the SORM concept is a tool for taking into account all the various factors and producing a recommendation for what would be the optimal runway configuration, runway use strategy, and aircraft sequence, considering as many of the relevant factors required in making this type of decision, and user preferences, if feasible. Three separate tools were initially envisioned for this research area, corresponding to the time scale in which they would operate: Strategic RCM (SRCM), with a planning horizon on the order of several hours, Tactical RCM (TRCM), with a planning horizon on the order of 90 minutes, and CADRS, with a planning horizon on the order of 15-30 minutes[1]. Algorithm development was initiated in all three of these areas, but the most fully developed to date is the TRCM algorithm. Earlier studies took a high-level approach to benefits, estimating aggregate benefits across most of the major airports in the National Airspace Systems (NAS), for both RCM and CADRS [2]. Other studies estimated the benefit of RCM and CADRS using various methods of re-sequencing arrivals to reduce delays3,4, or better balancing of arrival fixes5,6. Additional studies looked at different methods for performing the optimization involved in selecting the best Runway Configuration Plan (RCP) to use7-10. Most of these previous studies were high

Airports and Airfields, Airports within Johnson County as well as runway depicted with attribute information of both airport and runway., Published in Not Provided, Johnson County Government.

Data.gov (United States)

NSGIC Local Govt | GIS Inventory — Airports and Airfields dataset current as of unknown. Airports within Johnson County as well as runway depicted with attribute information of both airport and runway..

A surface embossing technique to create micro-grooves on an aluminum fin stock for drainage enhancement

International Nuclear Information System (INIS)

Liu Liping; Jacobi, Anthony M; Chvedov, Dmitri

2009-01-01

Recent advances using a surface embossing technique allow us to inexpensively impart micro-scale surface features on heat exchanger construction material, which we exploit to reduce condensate retention. The retention of condensate is important to the performance of heat exchangers in a broad range of air-cooling and dehumidification applications. We report a study of wetting behavior and drainage performance on a series of embossed surfaces with different micro-groove dimensions. Static contact angles, critical sliding angles, droplet aspect ratios, etc, are reported with detailed surface topographical information. Our results show that unless the spacing between grooves is very large (>100 µm), the parallel-grooved surface feature normally increases the apparent contact angle of a droplet on the surface. The micro-groove structure causes anisotropic wetting behavior of the droplets, and apparent contact angles measured by viewing along with the micro-grooves (θ p erpendicular) were found to be larger than those measured from the other direction (θ || ) (by viewing perpendicular to the grooves). A consistent reduction of a critical sliding angle was observed on surfaces after embossing (the micro-grooves are aligned to be parallel with gravity). This may be due to contact line discontinuities and contact-line pinning induced by a groove structure of the surface. Water droplets exhibit an elongated shape along the micro-grooves, which is in contrast to the nearly circular base contour observed on an isotropic surface. Smaller groove spacing, larger depth and steeper sidewalls are observed to be favorable for drainage enhancement and recommended as design guidelines in the future

Weather and forecasting at Wilkins ice runway, Antarctica

International Nuclear Information System (INIS)

Carpentier, Scott

2010-01-01

Aviation forecasts for Wilkins ice runway in East Antarctica are developed within the conceptual framework of flow against a single dome shaped hill. Forecast challenges include the sudden onset of blizzards associated with the formation of an internal gravity wave; frontal weather; transient wake vortices and mesoscale lows; temperature limitations on runway use; and snow and fog events. These key weather aspects are presented within the context of synoptic to local scale climatologies and numerical weather prediction models.

Erosion of a grooved surface caused by impact of particle-laden flow

Science.gov (United States)

Jung, Sohyun; Yang, Eunjin; Kim, Ho-Young

2016-11-01

Solid erosion can be a life-limiting process for mechanical elements in erosive environments, thus it is of practical importance in many industries such as construction, mining, and coal conversion. Erosion caused by particle-laden flow occurs through diverse mechanisms, such as cutting, plastic deformation, brittle fracture, fatigue and melting, depending on particle velocity, total particle mass and impingement angle. Among a variety of attempts to lessen erosion, here we investigate the effectiveness of millimeter-sized grooves on the surface. By experimentally measuring the erosion rates of smooth and triangular-grooved surfaces under various impingement angles, we find that erosion can be significantly reduced within a finite range of impingement angles. We show that such erosion resistance is attributed to the swirls of air within grooves and the differences in erosive strength of normal and slanted impact. In particular, erosion is mitigated when we increase the effective area under normal impact causing plastic deformation and fracture while decreasing the area under slanted impact that cuts the surface to a large degree. Our quantitative model for the erosion rate of grooved surfaces considering the foregoing effects agrees with the measurement results.

Investigation of innovative steel runway beam in industrial building

Indian Academy of Sciences (India)

The design of a runway beam for overhead cranes is of great importance ... The weight of the crane bridge and wheel spacing for the specific crane .... Name of model h (mm) b (mm) t (mm) s (mm) L (mm). Simple. 500. 300. 12. 6 ... load is 10.59 kN, crane runway beam span is 6,160 mm, and crane wheel base is 1,200 mm.

DNA minor groove alkylating agents.

Science.gov (United States)

Denny, W A

2001-04-01

Recent work on a number of different classes of anticancer agents that alkylate DNA in the minor groove is reviewed. There has been much work with nitrogen mustards, where attachment of the mustard unit to carrier molecules can change the normal patterns of both regio- and sequence-selectivity, from reaction primarily at most guanine N7 sites in the major groove to a few adenine N3 sites at the 3'-end of poly(A/T) sequences in the minor groove. Carrier molecules discussed for mustards are intercalators, polypyrroles, polyimidazoles, bis(benzimidazoles), polybenzamides and anilinoquinolinium salts. In contrast, similar targeting of pyrrolizidine alkylators by a variety of carriers has little effect of their patterns of alkylation (at the 2-amino group of guanine). Recent work on the pyrrolobenzodiazepine and cyclopropaindolone classes of natural product minor groove binders is also reviewed.

Influence of musical groove on postural sway.

Science.gov (United States)

Ross, Jessica M; Warlaumont, Anne S; Abney, Drew H; Rigoli, Lillian M; Balasubramaniam, Ramesh

2016-03-01

Timescales of postural fluctuation reflect underlying neuromuscular processes in balance control that are influenced by sensory information and the performance of concurrent cognitive and motor tasks. An open question is how postural fluctuations entrain to complex environmental rhythms, such as in music, which also vary on multiple timescales. Musical groove describes the property of music that encourages auditory-motor synchronization and is used to study voluntary motor entrainment to rhythmic sounds. The influence of groove on balance control mechanisms remains unexplored. We recorded fluctuations in center of pressure (CoP) of standing participants (N = 40) listening to low and high groove music and during quiet stance. We found an effect of musical groove on radial sway variability, with the least amount of variability in the high groove condition. In addition, we observed that groove influenced postural sway entrainment at various temporal scales. For example, with increasing levels of groove, we observed more entrainment to shorter, local timescale rhythmic musical occurrences. In contrast, we observed more entrainment to longer, global timescale features of the music, such as periodicity, with decreasing levels of groove. Finally, musical experience influenced the amount of postural variability and entrainment at local and global timescales. We conclude that groove in music and musical experience can influence the neural mechanisms that govern balance control, and discuss implications of our findings in terms of multiscale sensorimotor coupling. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

A Runway Surface Monitor using Internet of Things

Science.gov (United States)

Troiano, Amedeo; Pasero, Eros

2014-05-01

The monitoring of runway surfaces, for the detection of ice formation or presence of water, is an important issue for reducing maintenance costs and improving traffic safety. An innovative sensor was developed to detect the presence of ice or water on its surface, and its repeatability, stability and reliability were assessed in different simulations and experiments, performed both in laboratory and in the field. Three sensors were embedded in the runway of the Turin-Caselle airport, in the north-west of Italy, to check the state of its surface. Each sensor was connected to a GPRS modem to send the collected data to a common database. The entire system was installed about three years ago, and up to now it shows correct work and automatic reactivation after malfunctions without any external help. The state of the runway surface is virtual represented in an internet website, using the Internet of Things features and opening new scenarios.

Spot and Runway Departure Advisor

Science.gov (United States)

Jung, Yoon Chul

2013-01-01

The Spot and Runway Departure Advisor (SARDA) is a research prototype of a decision support tool for ATC tower controllers to assist in manging and controlling traffic on the surface of an airport. SARDA employs a scheduler to generate an optimal runway schedule and gate push-back - spot release sequence and schedule that improves efficiency of surface operations. The advisories for ATC tower controllers are displayed on an Electronic Flight Strip (EFS) system. The human-in-the-loop simulation of the SARDA tool was conducted for east operations of Dallas-Ft. Worth International Airport (DFW) to evaluate performance of the SARDA tool and human factors, such as situational awareness and workload. The results indicates noticeable taxi delay reduction and fuel savings by using the SARDA tool. Reduction in controller workload were also observed throughout the scenario runs. The future plan includes modeling and simulation of the ramp operations of the Charlotte International Airport, and develop a decision support tool for the ramp controllers.

Dual-phase CT findings of groove pancreatitis

Energy Technology Data Exchange (ETDEWEB)

Zaheer, Atif, E-mail: azaheer1@jhmi.edu [The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, Baltimore, MD 21231 (United States); Pancreatitis Center, Division of Gastroenterology, Department of Medicine, Johns Hopkins Medical Institutions, Baltimore, MD 21231 (United States); Haider, Maera, E-mail: mhaider3@jhmi.edu [The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, Baltimore, MD 21231 (United States); Kawamoto, Satomi, E-mail: skawamo1@jhmi.edu [The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, Baltimore, MD 21231 (United States); Hruban, Ralph H., E-mail: rhruban1@jhmi.edu [Department of Pathology, The Sol Goldman Pancreatic Cancer Research Center, the Johns Hopkins University School of Medicine, Baltimore, MD 21231 (United States); Fishman, Elliot K., E-mail: efishma1@jhmi.edu [The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, Baltimore, MD 21231 (United States)

2014-08-15

Purpose: Groove pancreatitis is a rare focal form of chronic pancreatitis that occurs in the pancreaticoduodenal groove between the major and minor papillae, duodenum and pancreatic head. Radiologic appearance and clinical presentation can result in suspicion of malignancy rendering pancreaticoduodenectomy inevitable. This study reports dual phase CT findings in a series of 12 patients with pathology proven groove pancreatitis. Materials and methods: Retrospective review of preoperative CT findings in 12 patients with histologically proven groove pancreatitis after pancreaticoduodenectomy. Size, location, attenuation, presence of mass or cystic components in the pancreas, groove and duodenum, calcifications, duodenal stenosis and ductal changes were recorded. Clinical data, laboratory values, endoscopic ultrasonographic and histopathological findings were collected. Results: Soft tissue thickening in the groove was seen in all patients. Pancreatic head, groove and duodenum were all involved in 75% patients. A discrete lesion in the pancreatic head was seen in half of the patients, most of which appeared hypodense on both arterial and venous phases. Cystic changes in pancreatic head were seen in 75% patients. Duodenal involvement was seen in 92% patients including wall thickening and cyst formation. The main pancreatic duct was dilated in 7 patients, with an abrupt cut off in 3 and a smooth tapering stricture in 4. Five patients had evidence of chronic pancreatitis with parenchymal calcifications. Conclusion: Presence of mass or soft tissue thickening in the groove with cystic duodenal thickening is highly suggestive of groove pancreatitis. Recognizing common radiological features may help in diagnosis and reduce suspicion of malignancy.

First branchial groove anomaly.

Science.gov (United States)

Kumar, M; Hickey, S; Joseph, G

2000-06-01

First branchial groove anomalies are very rare. We report a case of a first branchial groove anomaly presented as an infected cyst in an 11-month-old child. Management of such lesions is complicated because of their close association with the facial nerve. Surgical management must include identification and protection of the facial nerve. Embryology and facial nerve disposition in relation to the anomaly are reviewed.

An assessment of predominant causal factors of pilot deviations that contribute to runway incursions

Science.gov (United States)

Campbell, Denado M.

The aim of this study was to identify predominant causal factors of pilot deviations in runway incursions over a two-year period. Runway incursion reports were obtained from NASA's Aviation Safety Reporting System (ASRS), and a qualitative method was used by classifying and coding each report to a specific causal factor(s). The causal factors that were used were substantiated by research from the Aircraft Owner's and Pilot's Association that found that these causal factors were the most common in runway incursion incidents and accidents. An additional causal factor was also utilized to determine the significance of pilot training in relation to runway incursions. From the reports examined, it was found that miscommunication and situational awareness have the greatest impact on pilots and are most often the major causes of runway incursions. This data can be used to assist airports, airlines, and the FAA to understand trends in pilot deviations, and to find solutions for specific problem areas in runway incursion incidents.

Numerical analysis of flow in a centrifugal compressor with circumferential grooves: influence of groove location and number on flow instability

Science.gov (United States)

Chen, X.; Qin, G.; Ai, Z.; Ji, Y.

2017-08-01

As an effective and economic method for flow range enhancement, circumferential groove casing treatment (CGCT) is widely used to increase the stall margin of compressors. Different from traditional grooved casing treatments, in which the grooves are always located over the rotor in both axial and radial compressors, one or several circumferential grooves are located along the shroud side of the diffuser passage in this paper. Numerical investigations were conducted to predict the performance of a low flow rate centrifugal compressor with CGCT in diffuser. Computational fluid dynamics (CFD) analysis is performed under stage environment in order to find the optimum location of the circumferential casing groove in consideration of stall margin enhancement and efficiency gain at design point, and the impact of groove number to the effect of this grooved casing treatment configuration in enhancing the stall margin of the compressor stage is studied. The results indicate that the centrifugal compressor with circumferential groove in vaned diffuser can obtain obvious improvement in the stall margin with sacrificing design efficiency a little. Efforts were made to study blade level flow mechanisms to determine how the CGCT impacts the compressor’s stall margin (SM) and performance. The flow structures in the passage, the tip gap, and the grooves as well as their mutual interactions were plotted and analysed.

Formation of grooves during the breakdown of a coal block by a water jet

Energy Technology Data Exchange (ETDEWEB)

Shavlovskii, S.S.

1979-02-01

A description is given of a method of coal excavation which provides for the initial formation of a grooved slit along the width of the opening equal in height to the diameter of the sinkhole. The formation of a groove in the coal block and the excavation of coal by water jets using the grooved crater method are illustrated in diagrams. Data are given on changes in the performance of the hydraulic jet in coal excavation in relation to the distance between the nozzle and the face and at given pressures in front of the nozzle. Functional relationships were mathematically constructed for the performance of the water jet in dimensionless coordinates. Data are also given on the comparative performance of a water jet when coal is excavated by the grooved funnel method and by hydraulic fracturing. The analytical computations indicate that the hydraulic fracturing of a coal block by water jets is economical with respect to the consumption of electric power and the unit rate of coal extraction, in addition to being a safe method. 4 references, 4 figures, 2 tables.

Laser grooving of surface cracks on hot work tool steel

Directory of Open Access Journals (Sweden)

D. Klobčar

2011-10-01

Full Text Available The paper presents the analysis of laser grooving of 1.2343 tool steel hardened to 46 HRC. The effect of laser power and grooving speed on groove shape (i.e. depth and width, the material removal rate and the purity of produced groove as a measure of groove quality was investigated and analyzed using response surface methodology. Optimal parameters of laser grooving were found, which enables pure grooves suitable for laser welding.

EDM Electrode for Internal Grooves

Science.gov (United States)

Ramani, V.; Werner, A.

1985-01-01

Electroerosive process inexpensive alternative to broaching. Hollow brass electrodes, soldered at one end to stainless-steel holding ring, held in grooves in mandrel. These electrodes used to machine grooves electrically in stainless-steel tube three-eights inch (9.5 millimeters) in diameter. Tool used on tubes already in place in equipment.

Wetting morphologies and their transitions in grooved substrates

Energy Technology Data Exchange (ETDEWEB)

Seemann, Ralf; Bommer, Stefan; Herrmann, Carsten; Michler, Dominik [Experimental Physics, Saarland University, D-66123 Saarbruecken (Germany); Brinkmann, Martin; Herminghaus, Stephan; Khare, Krishnacharya; Kostourou, Konstantina; Gurevich, Evgeny [Max Planck Institute for Dynamics and Self-Organization, D-37073 Goettingen (Germany); Law, Bruce M; McBride, Sean, E-mail: r.seemann@physik.uni-saarland.de [Department of Physics, Kansas State University, Manhattan, KS 66506 (United States)

2011-05-11

When exposed to a partially wetting liquid, many natural and artificial surfaces equipped with complex topographies display a rich variety of liquid interfacial morphologies. In the present article, we focus on a few simple paradigmatic surface topographies and elaborate on the statics and dynamics of the resulting wetting morphologies. It is demonstrated that the spectrum of wetting morphologies increases with increasing complexity of the groove structure. On elastically deformable substrates, additional structures in the liquid morphologies can be observed, which are caused by deformations of the groove geometry in the presence of capillary forces. The emergence of certain liquid morphologies in grooves can be actively controlled by changes in wettability and geometry. For electrically conducting solid substrates, the apparent contact angle can be varied by electrowetting. This allows, depending on groove geometry, a reversible or irreversible transport of liquid along surface grooves. In the case of irreversible liquid transport in triangular grooves, the dynamics of the emerging instability is sensitive to the apparent hydrodynamic slip at the substrate. On elastic substrates, the geometry can be varied in a straightforward manner by stretching or relaxing the sample. The imbibition velocity in deformable grooves is significantly reduced compared to solid grooves, which is a result of the microscopic deformation of the elastic groove material close to the three phase contact line.

Strengthening air traffic safety management by moving from outcome-based towards risk-based evaluation of runway incursions

International Nuclear Information System (INIS)

Stroeve, Sybert H.; Som, Pradip; Doorn, Bas A. van; Bakker, G.J.

2016-01-01

Current safety management of aerodrome operations uses judgements of severity categories to evaluate runway incursions. Incident data show a small minority of severe incursions and a large majority of less severe incursions. We show that these severity judgements are mainly based upon the outcomes of runway incursions, in particular on the closest distances attained. As such, the severity-based evaluation leads to coincidental safety management feedback, wherein causes and risk implications of runway incursions are not well considered. In this paper we present a new framework for the evaluation of runway incursions, which effectively uses all runway incursions, which judges same types of causes similarly, and which structures causes and risk implications. The framework is based on risks of scenarios associated with the initiation of runway incursions. As a basis an inventory of scenarios is provided, which can represent almost all runway incursions involving a conflict with an aircraft. A main step in the framework is the assessment of the conditional probability of a collision given a runway incursion scenario. This can be effectively achieved for large sets of scenarios by agent-based dynamic risk modelling. The results provide detailed feedback on risks of runway incursion scenarios, thus enabling effective safety management. - Highlights: • Current evaluation of runway incursions is primarily based on their outcomes. • A new framework assesses collision risk given initiation of runway incursions. • Agent-based dynamic risk modelling can evaluate the risks of many scenarios. • A developed scenario inventory can represent almost all runway incursions. • The framework provides detailed feedback to safety management.

Exploration of the Theoretical Physical Capacity of the John F. Kennedy International Airport Runway System

Science.gov (United States)

Neitzke, Kurt W.; Guerreiro, Nelson M.

2014-01-01

A design study was completed to explore the theoretical physical capacity (TPC) of the John F. Kennedy International Airport (KJFK) runway system for a northflow configuration assuming impedance-free (to throughput) air traffic control functionality. Individual runways were modeled using an agent-based, airspace simulation tool, the Airspace Concept Evaluation System (ACES), with all runways conducting both departures and arrivals on a first-come first-served (FCFS) scheduling basis. A realistic future flight schedule was expanded to 3.5 times the traffic level of a selected baseline day, September 26, 2006, to provide a steady overdemand state for KJFK runways. Rules constraining departure and arrival operations were defined to reflect physical limits beyond which safe operations could no longer be assumed. Safety buffers to account for all sources of operational variability were not included in the TPC estimate. Visual approaches were assumed for all arrivals to minimize inter-arrival spacing. Parallel runway operations were assumed to be independent based on lateral spacing distances. Resulting time intervals between successive airport operations were primarily constrained by same-runway and then by intersecting-runway spacing requirements. The resulting physical runway capacity approximates a theoretical limit that cannot be exceeded without modifying runway interaction assumptions. Comparison with current KJFK operational limits for a north-flow runway configuration indicates a substantial throughput gap of approximately 48%. This gap may be further analyzed to determine which part may be feasibly bridged through the deployment of advanced systems and procedures, and which part cannot, because it is either impossible or not cost-effective to control. Advanced systems for bridging the throughput gap may be conceptualized and simulated using this same experimental setup to estimate the level of gap closure achieved.

A Robust Vision-based Runway Detection and Tracking Algorithm for Automatic UAV Landing

KAUST Repository

Abu Jbara, Khaled F.

2015-05-01

This work presents a novel real-time algorithm for runway detection and tracking applied to the automatic takeoff and landing of Unmanned Aerial Vehicles (UAVs). The algorithm is based on a combination of segmentation based region competition and the minimization of a specific energy function to detect and identify the runway edges from streaming video data. The resulting video-based runway position estimates are updated using a Kalman Filter, which can integrate other sensory information such as position and attitude angle estimates to allow a more robust tracking of the runway under turbulence. We illustrate the performance of the proposed lane detection and tracking scheme on various experimental UAV flights conducted by the Saudi Aerospace Research Center. Results show an accurate tracking of the runway edges during the landing phase under various lighting conditions. Also, it suggests that such positional estimates would greatly improve the positional accuracy of the UAV during takeoff and landing phases. The robustness of the proposed algorithm is further validated using Hardware in the Loop simulations with diverse takeoff and landing videos generated using a commercial flight simulator.

Anisotropic wetting properties on a precision-ground micro-V-grooved Si surface related to their micro-characterized variables

International Nuclear Information System (INIS)

Li, P; Xie, J; Cheng, J; Wu, K K

2014-01-01

Micro-characterized variables are proposed to precisely characterize a micro-V-grooved Si surface through the 3D measured topography rather than the designed one. In this study, level and gradient micro-grooved surfaces with depth of 25–80 µm were precisely and smoothly fabricated using a new micro-grinding process rather than laser machining and chemical etching. The objective is to investigate how these accurate micro-characterized variables systematically influence anisotropic wetting and droplet self-movement on such regular micro-structured surfaces without surface chemical modification. First, the anisotropic wetting, droplet sliding, pinning effect and droplet impact were experimentally investigated; then, theoretical anisotropic wetting models were constructed to predict and design the anisotropic wetting. The experiments show that the level micro-V-grooved surface produces the anisotropic wetting and pinning effects. It not only approximates superhydrophobicity but also produces high surface free energy. Moreover, the gradient micro-V-grooved surface with large pitch may lead to much easier droplet sliding than the level one along the micro-groove. The droplet self-movement trend increases with increasing the micro-groove gradient and micro-V-groove ratio. The micro-groove pitch and depth also influence the droplet impact. Theoretical analyses show that the wetting anisotropy and the droplet anisotropy both reach their largest value and disappear for a sharp micro-groove top when the micro-V-groove ratio is equal to 0.70 and 2.58, respectively, which may change the wetting between the composite state and the non-composite state. It is confirmed that the wetting behavior may be designed and predicted by the accurate micro-characterized variables of a regular micro-structured surface. (paper)

Anisotropic wetting properties on a precision-ground micro-V-grooved Si surface related to their micro-characterized variables

Science.gov (United States)

Li, P.; Xie, J.; Cheng, J.; Wu, K. K.

2014-07-01

Micro-characterized variables are proposed to precisely characterize a micro-V-grooved Si surface through the 3D measured topography rather than the designed one. In this study, level and gradient micro-grooved surfaces with depth of 25-80 µm were precisely and smoothly fabricated using a new micro-grinding process rather than laser machining and chemical etching. The objective is to investigate how these accurate micro-characterized variables systematically influence anisotropic wetting and droplet self-movement on such regular micro-structured surfaces without surface chemical modification. First, the anisotropic wetting, droplet sliding, pinning effect and droplet impact were experimentally investigated; then, theoretical anisotropic wetting models were constructed to predict and design the anisotropic wetting. The experiments show that the level micro-V-grooved surface produces the anisotropic wetting and pinning effects. It not only approximates superhydrophobicity but also produces high surface free energy. Moreover, the gradient micro-V-grooved surface with large pitch may lead to much easier droplet sliding than the level one along the micro-groove. The droplet self-movement trend increases with increasing the micro-groove gradient and micro-V-groove ratio. The micro-groove pitch and depth also influence the droplet impact. Theoretical analyses show that the wetting anisotropy and the droplet anisotropy both reach their largest value and disappear for a sharp micro-groove top when the micro-V-groove ratio is equal to 0.70 and 2.58, respectively, which may change the wetting between the composite state and the non-composite state. It is confirmed that the wetting behavior may be designed and predicted by the accurate micro-characterized variables of a regular micro-structured surface.

Double-grooved nanofibre surfaces with enhanced anisotropic hydrophobicity.

Science.gov (United States)

Liang, Meimei; Chen, Xin; Xu, Yang; Zhu, Lei; Jin, Xiangyu; Huang, Chen

2017-11-02

This study reports a facile method for fabricating double-grooved fibrous surfaces. The primary grooves of the surface are formed by aligned fibres, while the secondary grooves are achieved by oriented nanogrooves on the fibre surface. Investigation into the formation mechanism reveals that the nanogrooves can be readily tailored through adjusting the solvent ratio and relative humidity. With this understanding, a variety of polymers have been successfully electrospun into fibres having the same nanogrooved feature. These fibres show high resemblance to natural hierarchical structures, and thereby endowing the corresponding double-grooved surface with enhanced anisotropic hydrophobicity. A water droplet at a parallel direction to the grooves exhibits a much higher contact angle and a lower roll-off angle than the droplet at a perpendicular direction. The application potential of such anisotropic hydrophobicity has been demonstrated via a fog collection experiment, in which the double-grooved surface can harvest the largest amount of water. Moreover, the fabrication method requires neither post-treatment nor sophisticated equipment, making us anticipate that the double-grooved surface would be competitive in areas where a highly ordered surface, a large surface area and an anisotropic hydrophobicity are preferred.

Thermal Bridge Effects in Window Grooves

DEFF Research Database (Denmark)

Rose, Jørgen

1997-01-01

In this report thermal bridge effects in window grooves are analyzed. The analysis is performed using different thicknesses of the window groove insulation, to evaluate what the optimal solution is.All analysis in the report is performed using both 2- and 3-dimensional numerical analysis....

Runway Wake Vortex, Crosswind, and Visibility Detection with a Scintillometer at Schiphol Airport

NARCIS (Netherlands)

Dinther, van D.; Hartogensis, O.K.; Holtslag, A.A.M.

2015-01-01

We evaluate the performance and investigate the capability of a scintillometer to detect wake vortices, crosswind and visibility near an airport runway. An experiment is carried out at Schiphol airport (Amsterdam, The Netherlands), where an optical scintillometer is positioned alongside a runway. An

Predictor of Airport Runway Capacity (PARC), Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Estimates of arrival and departure capacities of individual airport runways are used to predict occurrences of demand-capacity imbalance, and to meter arrivals and...

Graphical User Interface Development and Design to Support Airport Runway Configuration Management

Science.gov (United States)

Jones, Debra G.; Lenox, Michelle; Onal, Emrah; Latorella, Kara A.; Lohr, Gary W.; Le Vie, Lisa

2015-01-01

The objective of this effort was to develop a graphical user interface (GUI) for the National Aeronautics and Space Administration's (NASA) System Oriented Runway Management (SORM) decision support tool to support runway management. This tool is expected to be used by traffic flow managers and supervisors in the Airport Traffic Control Tower (ATCT) and Terminal Radar Approach Control (TRACON) facilities.

Runway exit designs for capacity improvement demonstrations. Phase 2: Computer model development

Science.gov (United States)

Trani, A. A.; Hobeika, A. G.; Kim, B. J.; Nunna, V.; Zhong, C.

1992-01-01

The development is described of a computer simulation/optimization model to: (1) estimate the optimal locations of existing and proposed runway turnoffs; and (2) estimate the geometric design requirements associated with newly developed high speed turnoffs. The model described, named REDIM 2.0, represents a stand alone application to be used by airport planners, designers, and researchers alike to estimate optimal turnoff locations. The main procedures are described in detail which are implemented in the software package and possible applications are illustrated when using 6 major runway scenarios. The main output of the computer program is the estimation of the weighted average runway occupancy time for a user defined aircraft population. Also, the location and geometric characteristics of each turnoff are provided to the user.

Intentional replantation: A viable alternative for management of palatogingival groove

Directory of Open Access Journals (Sweden)

Vijay Kumar

2013-01-01

Full Text Available Radicular groove is an anatomical malformation that often leads to combined endodontic-periodontic lesions. Treatment of complex groove presents a clinical challenge to the operator. A case of type III palatogingival groove is successfully treated with intentional replantation. With the understanding of the procedure and strict adherence to guidelines improves, practitioners can use intentional replantation as an easy and cost-effective alternative for the management of radicular groove. The paper presents a brief review of palatogingival groove and highlights an easy and predictable alternative for its management.

Benefits Assessment for Tactical Runway Configuration Management Tool

Science.gov (United States)

Oseguera-Lohr, Rosa; Phojanamongkolkij, Nipa; Lohr, Gary; Fenbert, James W.

2013-01-01

The Tactical Runway Configuration Management (TRCM) software tool was developed to provide air traffic flow managers and supervisors with recommendations for airport configuration changes and runway usage. The objective for this study is to conduct a benefits assessment at Memphis (MEM), Dallas Fort-Worth (DFW) and New York's John F. Kennedy (JFK) airports using the TRCM tool. Results from simulations using the TRCM-generated runway configuration schedule are compared with results using historical schedules. For the 12 days of data used in this analysis, the transit time (arrival fix to spot on airport movement area for arrivals, or spot to departure fix for departures) for MEM departures is greater (7%) than for arrivals (3%); for JFK, there is a benefit for arrivals (9%) but not for departures (-2%); for DFW, arrivals show a slight benefit (1%), but this is offset by departures (-2%). Departure queue length benefits show fewer aircraft in queue for JFK (29%) and MEM (11%), but not for DFW (-13%). Fuel savings for surface operations at MEM are seen for both arrivals and departures. At JFK there are fuel savings for arrivals, but these are offset by increased fuel use for departures. In this study, no surface fuel benefits resulted for DFW. Results suggest that the TRCM algorithm requires modifications for complex surface traffic operations that can cause taxi delays. For all three airports, the average number of changes in flow direction (runway configuration) recommended by TRCM was many times greater than the historical data; TRCM would need to be adapted to a particular airport's needs, to limit the number of changes to acceptable levels. The results from this analysis indicate the TRCM tool can provide benefits at some high-capacity airports. The magnitude of these benefits depends on many airport-specific factors and would require adaptation of the TRCM tool; a detailed assessment is needed prior to determining suitability for a particular airport.

Mitigation of low-frequency groundnoise from runways

NARCIS (Netherlands)

Eerden, F.J.M. van der; Salomons, E.M.; Beeks, A.A.F.M.

2007-01-01

With the extra runway at Amsterdam Schiphol Airport, introduced in 2003, the noise nuisance for local residents increased due to increased groundnoise. In a case study the effect of enhanced ground absorption on the propagation of low-frequency noise from aircraft ground operations, e.g. departing

Spiral groove seal. [for rotating shaft

Science.gov (United States)

Ludwig, L. P.; Strom, T. N. (Inventor)

1974-01-01

Mating flat surfaces inhibit leakage of a fluid around a stationary shaft. A spiral groove produces a pumping action toward the fluid when the shaft rotates. This prevents leakage while a generated hydraulic lifting force separates the mating surfaces to minimize wear. Provision is made for placing these spiral grooves in communication with the fluid to accelerate the generation of the hydraulic lifting force.

Intentional replantation: A viable alternative for management of palatogingival groove

OpenAIRE

Vijay Kumar; Ajay Logani; Naseem Shah

2013-01-01

Radicular groove is an anatomical malformation that often leads to combined endodontic-periodontic lesions. Treatment of complex groove presents a clinical challenge to the operator. A case of type III palatogingival groove is successfully treated with intentional replantation. With the understanding of the procedure and strict adherence to guidelines improves, practitioners can use intentional replantation as an easy and cost-effective alternative for the management of radicular groove. The ...

Syncopation, body-movement and pleasure in groove music.

OpenAIRE

Witek, MA; Clarke, EF; Wallentin, M; Kringelbach, ML; Vuust, P

2014-01-01

Moving to music is an essential human pleasure particularly related to musical groove. Structurally, music associated with groove is often characterised by rhythmic complexity in the form of syncopation, frequently observed in musical styles such as funk, hip-hop and electronic dance music. Structural complexity has been related to positive affect in music more broadly, but the function of syncopation in eliciting pleasure and body-movement in groove is unknown. Here we report results from a ...

Plasma interaction with emmissive surface with Debye-scale grooves

Science.gov (United States)

Schweigert, Irina; Burton, Thomas S.; Thompson, Gregory B.; Langendorf, Samuel; Walker, Mitchell L. R.; Keidar, Michael

2018-04-01

The sheath development over emissive grooved surface in dc discharge plasma controlled by an electron beam is studied in the experiment and in 2D kinetic simulations. Grooved hexagonal boron nitride surfaces with different aspect ratios, designed to mimic the erosion channels, were exposed to an argon plasma. The characteristic size of the grooves (1 mm and 5 mm) is about of the Debye length. The secondary electrons emission from the grooved surfaces is provided by the bombardment with energetic electrons originated from the heated powered cathode. The transition between a developed and a collapsed sheaths near emissive surface takes place with an increase of the beam electron energy. For grooved emissive surfaces, the sheath transition happens at essentially higher voltage compared to the planar one. This phenomenon is analyzed in the terms of the electron energy distribution function.

Mixed convection in a baffled grooved channel

Indian Academy of Sciences (India)

MS received 16 May 2014; revised 19 October 2014; accepted 06 November 2014. Abstract. In the present numerical work, flow structure and heat transfer charac- teristics are investigated in a baffled grooved channel, differentially heated from the sides. The baffle is placed vertically downward from the top wall of grooved ...

Research on performance of upstream pumping mechanical seal with different deep spiral groove

International Nuclear Information System (INIS)

Wang, Q; Chen, H L; Liu, T; Liu, Y H; Liu, Z B; Liu, D H

2012-01-01

As one new type of mechanical seal, Upstream Pumping Mechanical Seal has been widely used in fluid machinery. In this paper, structure of spiral groove is innovatively optimized to improve performance of Upstream Pumping Mechanical Seal with Spiral Groove: keeping the dam zone and the weir zone not changed, changing the bottom shape of spiral groove only, substituting different deep spiral groove for equal deep spiral groove. The simulation on Upstream Pumping Mechanical Seal with different deep spiral grooves is done using FVM method. According to calculation, the performances of opening force and pressure distribution on seals face are obtained. Five types of spiral grooves are analyzed, namely equal deep spiral groove, circumferential convergent ladder-like different deep spiral groove, circumferential divergent ladder-like different deep spiral groove, radial convergent ladder-like different deep spiral groove and radial divergent ladder-like different deep spiral groove. This paper works on twenty-five working conditions. The results indicate the performances of circumferential divergent 2-ladder different deep spiral groove are better than the others, with more opening force and better stabilization, while with the same leakage. The outcome provides theoretical support for application of Upstream Pumping Mechanical Seal with circumferential convergent ladder-like different deep spiral groove.

Research on performance of upstream pumping mechanical seal with different deep spiral groove

Science.gov (United States)

Wang, Q.; Chen, H. L.; Liu, T.; Liu, Y. H.; Liu, Z. B.; Liu, D. H.

2012-11-01

As one new type of mechanical seal, Upstream Pumping Mechanical Seal has been widely used in fluid machinery. In this paper, structure of spiral groove is innovatively optimized to improve performance of Upstream Pumping Mechanical Seal with Spiral Groove: keeping the dam zone and the weir zone not changed, changing the bottom shape of spiral groove only, substituting different deep spiral groove for equal deep spiral groove. The simulation on Upstream Pumping Mechanical Seal with different deep spiral grooves is done using FVM method. According to calculation, the performances of opening force and pressure distribution on seals face are obtained. Five types of spiral grooves are analyzed, namely equal deep spiral groove, circumferential convergent ladder-like different deep spiral groove, circumferential divergent ladder-like different deep spiral groove, radial convergent ladder-like different deep spiral groove and radial divergent ladder-like different deep spiral groove. This paper works on twenty-five working conditions. The results indicate the performances of circumferential divergent 2-ladder different deep spiral groove are better than the others, with more opening force and better stabilization, while with the same leakage. The outcome provides theoretical support for application of Upstream Pumping Mechanical Seal with circumferential convergent ladder-like different deep spiral groove.

V-groove plasmonic waveguides fabricated by nanoimprint lithography

DEFF Research Database (Denmark)

Fernandez-Cuesta, I.; Nielsen, R.B.; Boltasseva, Alexandra

2007-01-01

Propagation of channel plasmon-polariton modes in the bottom of a metal V groove has been recently demonstrated. It provides a unique way of manipulating light at nanometer length scale. In this work, we present a method based on nanoimprint lithography that allows parallel fabrication of integra...... of integrated optical devices composed of metal V grooves. This method represents an improvement with respect to previous works, where the V grooves were fabricated by direct milling of the metal, in terms of robustness and throughput. © 2007 American Vacuum Society......Propagation of channel plasmon-polariton modes in the bottom of a metal V groove has been recently demonstrated. It provides a unique way of manipulating light at nanometer length scale. In this work, we present a method based on nanoimprint lithography that allows parallel fabrication...

Reassessing the Function of Grooves in Mycenaean Tombs

Directory of Open Access Journals (Sweden)

Constantina Katsari

2001-11-01

Full Text Available Normal 0 0 2 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} Among the Chamber and Tholos Tombs that were built in Greece during the Late Helladic period are some that show a particular feature: a pair of grooves that are carved on the floor of the 'stomion '(a short corridor that leads inside the tomb, leading from the 'dromos '(a long road that leads towards the tomb itself into the chamber. Archaeologists have suggested a number of explanations regarding their function; however, none of these seems entirely plausible. In this article, we offer a different kind of hypothesis mostly based on architectural evidence. We will suggest that, rather than being related to ritual practices, the grooves were mainly used to facilitate the construction of the graves.

76 FR 67018 - Notice to Manufacturers of Airport In-Pavement Stationary Runway Weather Information Systems

Science.gov (United States)

2011-10-28

...-Pavement Stationary Runway Weather Information Systems AGENCY: Federal Aviation Administration (FAA), U.S. DOT. ACTION: Notice to Manufacturers of In-Pavement Stationary Runway Weather Information Systems... Operations. This notice requests information from manufacturers of systems meeting the technical requirements...

Comprehensive and Highly Accurate Measurements of Crane Runways, Profiles and Fastenings.

Science.gov (United States)

Dennig, Dirk; Bureick, Johannes; Link, Johannes; Diener, Dmitri; Hesse, Christian; Neumann, Ingo

2017-05-13

The process of surveying crane runways has been continually refined due to the competitive situation, modern surveying instruments, additional sensors, accessories and evaluation procedures. Guidelines, such as the International Organization for Standardization (ISO) 12488-1, define target values that must be determined by survey. For a crane runway these are for example the span, the position and height of the rails. The process has to be objective and reproducible. However, common processes of surveying crane runways do not meet these requirements sufficiently. The evaluation of the protocols, ideally by an expert, requires many years of experience. Additionally, the recording of crucial parameters, e.g., the wear of the rail, or the condition of the rail fastening and rail joints, is not regulated and for that reason are often not considered during the measurement. To solve this deficit the Advanced Rail Track Inspection System (ARTIS) was developed. ARTIS is used to measure the 3D position of crane rails, the cross-section of the crane rails, joints and, for the first time, the (crane-rail) fastenings. The system consists of a monitoring vehicle and an external tracking sensor. It makes kinematic observations with the tracking sensor from outside the rail run, e.g., the floor of an overhead crane runway, possible. In this paper we present stages of the development process of ARTIS, new target values, calibration of sensors and results of a test measurement.

Grooved Fuel Rings for Nuclear Thermal Rocket Engines

Science.gov (United States)

Emrich, William

2009-01-01

An alternative design concept for nuclear thermal rocket engines for interplanetary spacecraft calls for the use of grooved-ring fuel elements. Beyond spacecraft rocket engines, this concept also has potential for the design of terrestrial and spacecraft nuclear electric-power plants. The grooved ring fuel design attempts to retain the best features of the particle bed fuel element while eliminating most of its design deficiencies. In the grooved ring design, the hydrogen propellant enters the fuel element in a manner similar to that of the Particle Bed Reactor (PBR) fuel element.

Fractures of the proximal humerus involving the intertubercular groove

International Nuclear Information System (INIS)

Ahovuo, J.; Paavolainen, P.; Bjoerkenheim, J.M.; Helsinki Univ. Central Hospital

1989-01-01

The purpose of this study was to analyse the involvement of the gliding surface of the biceps tendon in fractures of the proximal humerus. Fifteen patients had a fracture of the proximal humerus verified with antero-posterior and axillary radiographs. Tangential radiographs of the intertubercular groove, obtained from the shoulder joint, showed involvement of the intertubercular groove in 13 patients (87%), which could not be shown with other projections. Groove radiographs revealed in 3 patients a dislocation of the fragments of the greater tuberosity large enough to require surgical treatment, but which had not been found using conventional techniques. Therefore, a groove radiograph should be used to precise fractures of the proximal humerus. (orig.)

Joint Rapid Airfield Construction (JRAC) 2007 Technology Demonstration

National Research Council Canada - National Science Library

Anderton, Gary L; Berney, IV, Ernest S; Mann, Travis A; Newman, J. K; Baylot, E. A; Miller, Daniel K; Mason, Quint

2008-01-01

...) unsurfaced runway and two 45,480-ft2 (4,225-m2) aircraft parking aprons with associated connector taxiways, all using JRAC technologies focused on rapid construction with reduced logistics and increased system reliability...

Evaluation of J-groove weld residual stress and crack growth rate of PWSCC in reactor pressure vessel closure head

Energy Technology Data Exchange (ETDEWEB)

Oh, Seung Hyuk; Ryu, Tae Young; Park, Seung Hyun; Won, Min Gu; Kang, Seok Jun; Kim, Moon Ki; Choi, Jae Boong [Sungkyunkwan University, Suwon (Korea, Republic of); Lee, Kyoung Soo; Lee, Sung Ho [Korea Hydro and Nuclear Power, Daejeon (Korea, Republic of)

2015-03-15

Over the last decade, primary water stress corrosion cracking (PWSCC) has been frequently found in pressurized water reactor (PWR) applications. Especially, PWSCC has occurred in long-term operated PWRs. As this phenomenon leads to serious accidents, we must be beforehand with the anticipated problems. A typical PWR consists of J-groove welded components such as reactor pressure vessel closure head and nozzles. Reactor pressure vessel closure head is made of SA508 and it is covered by cladding. Alloy 600 is used for nozzles. And J-groove weld is conducted with alloy 82/182. Different material properties of these metals lead to residual stress and PWSCC consequentially. In this study, J-groove weld residual stress was investigated by a three-dimensional finite element analysis with an actual asymmetric J-groove weld model and process of construction. Also crack growth rate of PWSCC was evaluated from cracks applied on the penetration nozzles. Based on these two values, one cannot only improve the structural integrity of PWR, but also explain PWSCC behavior such that high residual stress at the J-groove weld area causes crack initiation and propagation through the surface of nozzles. In addition, crack behavior was predicted at the various points around the nozzle.

Evaluation of J-groove weld residual stress and crack growth rate of PWSCC in reactor pressure vessel closure head

International Nuclear Information System (INIS)

Oh, Seung Hyuk; Ryu, Tae Young; Park, Seung Hyun; Won, Min Gu; Kang, Seok Jun; Kim, Moon Ki; Choi, Jae Boong; Lee, Kyoung Soo; Lee, Sung Ho

2015-01-01

Over the last decade, primary water stress corrosion cracking (PWSCC) has been frequently found in pressurized water reactor (PWR) applications. Especially, PWSCC has occurred in long-term operated PWRs. As this phenomenon leads to serious accidents, we must be beforehand with the anticipated problems. A typical PWR consists of J-groove welded components such as reactor pressure vessel closure head and nozzles. Reactor pressure vessel closure head is made of SA508 and it is covered by cladding. Alloy 600 is used for nozzles. And J-groove weld is conducted with alloy 82/182. Different material properties of these metals lead to residual stress and PWSCC consequentially. In this study, J-groove weld residual stress was investigated by a three-dimensional finite element analysis with an actual asymmetric J-groove weld model and process of construction. Also crack growth rate of PWSCC was evaluated from cracks applied on the penetration nozzles. Based on these two values, one cannot only improve the structural integrity of PWR, but also explain PWSCC behavior such that high residual stress at the J-groove weld area causes crack initiation and propagation through the surface of nozzles. In addition, crack behavior was predicted at the various points around the nozzle.

Computer-aided system for detecting runway incursions

Science.gov (United States)

Sridhar, Banavar; Chatterji, Gano B.

1994-07-01

A synthetic vision system for enhancing the pilot's ability to navigate and control the aircraft on the ground is described. The system uses the onboard airport database and images acquired by external sensors. Additional navigation information needed by the system is provided by the Inertial Navigation System and the Global Positioning System. The various functions of the system, such as image enhancement, map generation, obstacle detection, collision avoidance, guidance, etc., are identified. The available technologies, some of which were developed at NASA, that are applicable to the aircraft ground navigation problem are noted. Example images of a truck crossing the runway while the aircraft flies close to the runway centerline are described. These images are from a sequence of images acquired during one of the several flight experiments conducted by NASA to acquire data to be used for the development and verification of the synthetic vision concepts. These experiments provide a realistic database including video and infrared images, motion states from the Inertial Navigation System and the Global Positioning System, and camera parameters.

Runway Incursion Prevention System: Demonstration and Testing at the Dallas/Fort Worth International Airport

Science.gov (United States)

Jones, Denise R.; Quach, Cuong C.; Young, Steven D.

2007-01-01

A Runway Incursion Prevention System (RIPS) was tested at the Dallas-Ft. Worth International Airport (DFW) in October 2000. The system integrated airborne and ground components to provide both pilots and controllers with enhanced situational awareness, supplemental guidance cues, a real-time display of traffic information, and warning of runway incursions in order to prevent runway incidents while also improving operational capability. A series of test runs was conducted using NASA s Boeing 757 research aircraft and a test van equipped to emulate an incurring aircraft. The system was also demonstrated to over 100 visitors from the aviation community. This paper gives an overview of the RIPS, DFW flight test activities, and quantitative and qualitative results of the testing.

Experimental and Numerical Investigation on Tribological Performance of Grooved Texture

Directory of Open Access Journals (Sweden)

CHEN Ping

2016-06-01

Full Text Available In order to study the influence of the angle and arrangement forms of micro-grooves on the tribological performance of the contact surface, the finite element analysis software was used to simulate the grooved textures with different angles and arrangements. The YLP-20 laser processing system was used to process grooved texture on stainless steel disk surfaces, and the Tribometer (UMT-2 was also used to conduct tribological test under the condition of rotation. The results show that the numerical simulation values are basically consistent with experimental results of grooved textures, and the tribological performance of the friction pairs with textures is also improved. The grooved textures with different angles and arrangement forms have different influence on tribological performance of friction pairs. When the friction velocity is less than 300r/min, the parallel texture with 0° has smaller friction coefficients. While the friction velocity is larger than 300r/min, the parallel texture with 90° has a better ability of reducing friction. Therefore, different grooved textures should be chosen according to operation conditions.

A stereological approach for measuring the groove angles of intergranular corrosion

International Nuclear Information System (INIS)

Gwinner, B.; Borgard, J.-M.; Dumonteil, E.; Zoia, A.

2017-01-01

Highlights: • The ICG morphology has been characterized in 3D by X-ray μ-tomography. • The measurement of the angles of the IGC groove on 2D cross sections induces a bias. • A methodology is proposed to estimate the true value of the IGC groove angles in 3D. - Abstract: Non-sensitized austenitic stainless steels can be prone to intergranular corrosion when they are in contact with an oxidizing medium like nitric acid. Intergranular corrosion is characterized by the formation of grooves along the grain boundaries. The angle of these grooves is a key parameter, which directly informs of the intergranular corrosion kinetics. Most of the time, the angles of the grooves are experimentally measured on 2-dimensional cross sections of the corroded samples. This study discusses the relationship between the groove angle measured on 2-dimensional sections and the true groove angle in 3-dimensional space. This approach could also be easily extended to the study of crack angle in the domains of corrosion-fatigue, stress corrosion cracking or mechanical fracture.

Grooves on the occipital lobe of Indian brains.

OpenAIRE

Bisaria, K K

1984-01-01

The existence of a groove on the occipital lobe formed by the dural venous sinus or ridge has only rarely been described in the past. As observed in this study such grooves are either unilateral or bilateral and their incidence is very high in Indian brains.

Interproximal grooving in the Atapuerca-SH hominid dentitions.

Science.gov (United States)

Bermúdez de Castro, J M; Arsuaga, J L; Pérez, P J

1997-03-01

The dental sample recovered from the Sima de los Huesos (SH) Middle Pleistocene cave site of the Sierra de Atapuerca (Spain) includes 296 specimens. Interproximal wear grooves have been observed in 20 maxillary and mandibular posterior teeth belonging to at least five of the 32 individuals identified so far in the SH hypodigm. Interproximal grooving affected only the adults, and at an age between 25 and 40 years. The appearance, morphology, and location pattern of the SH wear grooves are similar to those reported in other fossil hominids and in more recent human populations. Two alternative proposals, the toothpicking and the fiber or sinew processing hypotheses, compete for explaining the formation of this anomalous wear. The characteristics observed in the wear grooves of the SH teeth are compatible only with the habitual probing of interdental spaces by means of hard and inflexible objects. Dietary grit may also have contributed to the abrasion of the root walls during the motion of the dental probes.

Soil settlement analysis in soft soil by using preloading system and prefabricated vertical draining runway of Kualanamu Airport

Science.gov (United States)

Roesyanto; Iskandar, R.; Silalahi, S. A.; Fadliansyah

2018-02-01

The method of soil improvement, using the combination of prefabricated vertical drain (PVD) and preloading, was used to accelerate the process of consolidation and the consolidation settlement in the runway of Kualanamu International Airport, which was constructed on the soft soil sediment like silty clay. In this research, the investigated area was the runway of Kualanamu International Airport zone I which had 11 meter-thickness of soft soil. Geotechnic instruments surveyed was settlement plate. Monitoring was done toward the behavior of landfill such as basic soil settlement. The result were compared with the analysis of finite element method of full scale in Mohr-Coulomb model by verifying the vertical drain of asymmetric unit cell and equivalent plane strain unit cell condition. The results of the research showed that there were an interesting behavior between the data in field observation and finite element of Mohr-Coulomb model. It was also found that the result of soil settlement of finite element method of Mohr-Coulomb model was closed to the result of settlement plate monitoring.

The MLC tongue-and-groove effect on IMRT dose distributions

Energy Technology Data Exchange (ETDEWEB)

Deng Jun [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305 (United States). E-mail: jun@reyes.stanford.edu; Pawlicki, Todd; Chen Yan; Li Jinsheng; Jiang, Steve B.; Ma, C.-M. [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305 (United States)

2001-04-01

We have investigated the tongue-and-groove effect on the IMRT dose distributions for a Varian MLC. We have compared the dose distributions calculated using the intensity maps with and without the tongue-and-groove effect. Our results showed that, for one intensity-modulated treatment field, the maximum tongue-and-groove effect could be up to 10% of the maximum dose in the dose distributions. For an IMRT treatment with multiple gantry angles ({>=} 5), the difference between the dose distributions with and without the tongue-and-groove effect was hardly visible, less than 1.6% for the two typical clinical cases studied. After considering the patient setup errors, the dose distributions were smoothed with reduced and insignificant differences between plans with and without the tongue-and-groove effect. Therefore, for a multiple-field IMRT plan ({>=} 5), the tongue-and-groove effect on the IMRT dose distributions will be generally clinically insignificant due to the smearing effect of individual fields. The tongue-and-groove effect on an IMRT plan with small number of fields (<5) will vary depending on the number of fields in a plan (coplanar or non-coplanar), the MLC leaf sequences and the patient setup uncertainty, and may be significant (>5% of maximum dose) in some cases, especially when the patient setup uncertainty is small ({<=} 2 mm). (author)

Vacuum sealing with a spiral grooved gas dynamic seal

International Nuclear Information System (INIS)

Sawada, Tadashi

1979-01-01

Gas dynamic seals with rectangular spiral grooves are studied theoretically taking the effects of sidewalls of the grooves and the effects of gas compressibility into account, and slip boundary conditions are employed. The results are compared with the existing experimental data and the validity of the theory is confirmed over a wide pressure range except for the extremely low pressures. Suggestions are made regarding the choice of the geometrical dimensions, i.e., aspect ratio, helix angle, clearance parameter and groove width ratio. (author)

Grooved windows for scintillation crystals and light pipes of high refractive index

International Nuclear Information System (INIS)

Swinehart, C.F.

1975-01-01

Scintillation crystals are disclosed which have improved resolution and pulse height. An improved crystal has shallow grooves or spot depressions cut in the window, usually an end surface. Typical grooves are about 1.5 mm wide and about .1 mm deep. The grooves may be either horizontal, generally parallel grooves in spaced apart relationship, or concentric rings in radially spaced apart relationship. A light pipe of high refractive index, such as a crystal of pure sodium iodide, may also be improved with shallow grooves or spot depressions cut in an end surface

Models for estimating runway landing capacity with Microwave Landing System (MLS)

Science.gov (United States)

Tosic, V.; Horonjeff, R.

1975-01-01

A model is developed which is capable of computing the ultimate landing runway capacity, under ILS and MLS conditions, when aircraft population characteristics and air traffic control separation rules are given. This model can be applied in situations when only a horizontal separation between aircraft approaching a runway is allowed, as well as when both vertical and horizontal separations are possible. It is assumed that the system is free of errors, that is that aircraft arrive at specified points along the prescribed flight path precisely when the controllers intend for them to arrive at these points. Although in the real world there is no such thing as an error-free system, the assumption is adequate for a qualitative comparison of MLS with ILS. Results suggest that an increase in runway landing capacity, caused by introducing the MLS multiple approach paths, is to be expected only when an aircraft population consists of aircraft with significantly differing approach speeds and particularly in situations when vertical separation can be applied. Vertical separation can only be applied if one of the types of aircraft in the mix has a very steep descent angle.

Appraisal of transverse nasal groove: a study.

Science.gov (United States)

Sathyanarayana, Belagola D; Basavaraj, Halevoor B; Nischal, Kuchangi C; Swaroop, Mukunda R; Umashankar, Puttagangu N; Agrawal, Dhruv P; Swamy, Suchetha S; Okram, Sarda

2012-01-01

Transverse nasal groove is a condition of cosmetic concern which awaits due recognition and has been widely described as a shallow groove that extends transversely over the dorsum of nose. However, we observed variations in the clinical presentations of this entity, hitherto undescribed in literature. We conducted a clinicoepidemiological study of transverse nasal lesions in patients attending our outpatient department. We conducted a prospective observational study. We screened all patients attending our out-patient department for presence of transverse nasal lesions, signs of any dermatosis and associated other skin conditions. One hundred patients were recruited in the study. Females (80%) predominated over males. Most patients were of 15-45 years age group (70%). Majority of the transverse nasal lesions were classical transverse nasal groove (39%) and others included transverse nasal line (28%), strip (28%), ridge (4%) and loop (1%). Seborrhoeic diathesis was the most common condition associated with transverse nasal lesion. Occurrence of transverse nasal line, strip, ridge and loop, in addition to classical transverse nasal groove implies that latter is actually a subset of transverse nasal lesions. Common association of this entity with seborrheic dermatitis, seborrhea and dandruff raises a possibility of whether transverse nasal lesion is a manifestation of seborrheic diathesis.

Characteristics of Multiplexed Grooved Nozzles for High Flow Rate Electrospray

International Nuclear Information System (INIS)

Kim, Kyoung Tae; Kim, Woo Jin; Kim, Sang Soo

2007-01-01

The electrospray operated in the cone-jet mode can generate highly charged micro droplets in an almost uniform size at flow rates. Therefore, the multiplexing system which can retain the characteristics of the cone-jet mode is inevitable for the electrospray application. This experiment reports the multiplexed grooved nozzle system with the extractor. The effects of the grooves and the extractor on the performance of the electrospray were evaluated through experiments. Using the grooved nozzle, the stable cone-jet mode can be achieved at the each groove in the grooved mode. Furthermore, the number of nozzles per unit area is increased by the extractor. The multiplexing density is 12 jets per cm 2 at 30 mm distance from the nozzle tip to the ground plate. The multiplexing system for the high flow rate electrospray is realized with the extractor which can diminish the space charge effect without sacrificing characteristics of the cone-jet mode

Grooves on the occipital lobe of Indian brains.

Science.gov (United States)

Bisaria, K K

1984-01-01

The existence of a groove on the occipital lobe formed by the dural venous sinus or ridge has only rarely been described in the past. As observed in this study such grooves are either unilateral or bilateral and their incidence is very high in Indian brains. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:6490537

Nanoscale Plasmonic V-Groove Waveguides for the Interrogation of Single Fluorescent Bacterial Cells.

Science.gov (United States)

Lotan, Oren; Bar-David, Jonathan; Smith, Cameron L C; Yagur-Kroll, Sharon; Belkin, Shimshon; Kristensen, Anders; Levy, Uriel

2017-09-13

We experimentally demonstrate the interrogation of an individual Escherichia coli cell using a nanoscale plasmonic V-groove waveguide. Several different configurations were studied. The first involved the excitation of the cell in a liquid environment because it flows on top of the waveguide nanocoupler, while the obtained fluorescence is coupled into the waveguide and collected at the other nanocoupler. The other two configurations involved the positioning of the bacterium within the nanoscale waveguide and its excitation in a dry environment either directly from the top or through waveguide modes. This is achieved by taking advantage of the waveguide properties not only for light guiding but also as a mechanical tool for trapping the bacteria within the V-grooves. The obtained results are supported by a set of numerical simulations, shedding more light on the mechanism of excitation. This demonstration paves the way for the construction of an efficient bioplasmonic chip for diverse cell-based sensing applications.

Enhanced heat transfer performances of molten salt receiver with spirally grooved pipe

International Nuclear Information System (INIS)

Lu, Jianfeng; Ding, Jing; Yu, Tao; Shen, Xiangyang

2015-01-01

The enhanced heat transfer performances of solar receiver with spirally grooved pipe were theoretically investigated. The physical model of heat absorption process was proposed using the general heat transfer correlation of molten salt in smooth and spirally grooved pipe. According to the calculation results, the convective heat transfer inside the receiver can remarkably enhance the heat absorption process, and the absorption efficiency increased with the flow velocity and groove height, while the wall temperature dropped. As the groove height increased, the heat losses of convection and radiation dropped with the decrease of wall temperature, and the average absorption efficiency of the heat receiver can be increased. Compared with the heat receiver with smooth pipe, the heat absorption efficiency of heat receiver with spirally grooved pipe e/d = 0.0475 can rise for 0.7%, and the maximum bulk fluid temperature can be increased for 31.1 °C. As a conclusion, spirally grooved pipe can be a very effective way for heat absorption enhancement of solar receiver, and it can also increase the operating temperature of molten salt. - Highlights: • Spirally grooved tube is a very effective way for solar receiver enhancement. • Heat absorption model of receiver is proposed with general heat transfer correlation. • Spirally groove tube increases absorption efficiency and reduces wall temperature. • Operating temperature of molten salt remarkably increases with groove height. • Heat absorption performance is promoted for first and second thermodynamics laws

Side-coupled cavity model for surface plasmon-polariton transmission across a groove

International Nuclear Information System (INIS)

Liu, J.S.Q.

2010-01-01

We demonstrate that the transmission properties of surface plasmon-polaritons (SPPs) across a rectangular groove in a metallic film can be described by an analytical model that treats the groove as a side-coupled cavity to propagating SPPs on the metal surface. The coupling efficiency to the groove is quantified by treating it as a truncated metal-dielectric-metal (MDM) waveguide. Finite-difference frequency-domain (FDFD) simulations and mode orthogonality relations are employed to derive the basic scattering coefficients that describe the interaction between the relevant modes in the system. The modeled SPP transmission and reflection intensities show excellent agreement with full-field simulations over a wide range of groove dimensions, validating this intuitive model. The model predicts the sharp transmission minima that occur whenever an incident SPP resonantly couples to the groove. We also for the first time show the importance of evanescent, reactive MDM SPP modes to the transmission behavior. SPPs that couple to this mode are resonantly enhanced upon reflection from the bottom of the groove, leading to high field intensities and sharp transmission minima across the groove. The resonant behavior exhibited by the grooves has a number of important device applications, including SPP mirrors, filters, and modulators.

Effect of groove on socket welds under the condition of vibration fatigue

International Nuclear Information System (INIS)

Xiu, Junjie; Jing, Hongyang; Han, Yongdian; Zhao, Lei; Xu, Lianyong

2013-01-01

Root failures of socket welds in small bore piping caused by vibration mainly occur at nuclear power plants (NPPs). It was observed that at higher stress level failures tended to originate at the toe while for the case of lower stress failures tended to occur at the root. The groove can increase the penetration depth (PD) of root, which is beneficial to the fatigue life. The effect of groove was also investigated by finite element method (FEM). The simulation results show that groove can decline the stress distribution, stress triaxiality and maximum principal plastic strain in the weld root, and the 5 mm groove suffering σ max (the highest stress of root failure) is almost same as no groove subjecting to σ f (fatigue limit). The test results show that the socket weld with groove can increase the natural frequency and damping of specimen, which make the system more difficult to vibrate. Moreover, the groove can also improve the fatigue property of specimen which do not exist the root failure even under high cycle fatigue (HCF)

Cold test of deep groove plarizer for 170 GHz ECCD system

International Nuclear Information System (INIS)

Saigusa, M.; Ookouti, K.; Sazawa, S.; Yuasa, S.; Takei, N.; Takahashi, K.; Sakamoto, K.; Imai, T.

2001-01-01

The single deep groove mirror was proposed as a new concept polarizer instead of the conventional two mirror polarizers for producing ordinary (or extraordinary) wave with high mode purity at an arbitrary injection angle in electron cyclotron current drive (ECCD) experiments. The estimated mode purity of O and X waves on the plasma surface is expected to be higher than about 93% for reasonable ECCD experimental conditions. The three types of deep groove mirrors, which are the rectangular groove mirror and the non-rectangular one, are manufactured and tested at the frequency range from 140 GHz to 170 GHz and the power level of 30 mW. The groove parameters are the period of 0.9-1 mm, the ridge width of 0.45-0.5 mm, and the groove depth of 1.98 mm, which is deeper than a wavelength at 170 GHz. The measured results of deep groove polarizers agree with the theoretical predictions, qualitatively. Those prove the feasibility of a single mirror polarizer for ECCD system

Heat transfer and thermal stress analysis in grooved tubes

Indian Academy of Sciences (India)

Heat transfer and thermal stresses, induced by temperature differencesin the internally grooved tubes of heat transfer equipment, have been analysed numerically. The analysis has been conducted for four different kinds of internally grooved tubes and three different mean inlet water velocities. Constant temperature was ...

Continuous blood fractionation using an array of slanted grooves

Science.gov (United States)

Bernate, Jorge A.; Chengxun, Liu; Lagae, Liesbet; Drazer, German

2011-11-01

Blood is a complex fluid having different specialized biological functions and containing a plethora of clinical information. The separation of different blood components is a crucial step in many research and clinical applications. In this work we take advantage of the flow characteristics in microfluidic devices in which the bottom surface is patterned with slanted rectangular grooves to continuously fractionate blood. We exploit the flow in the vicinity of the patterned surface when the dimensions of the grooves are much smaller than the dimensions of the main channel. In these devices, we observed that the grooves act as open channels guiding flow along them with the flow over them being in the direction of the main channel. We present experiments in which the different blood components are deflected laterally to a different extent by the flow along the grooves depending on their sedimentation velocity, which allows their continuous fractionation. In particular, the heavier red blood cells experience the largest deflection while the lighter white blood cells deflect the least, allowing their passive and minimally invasive isolation. In addition, this fluidic platform can also be used to separate magnetically labeled circulating cancer cells which can be retained in the flow along the grooves using a sufficiently strong magnetic force.

Design of pellet surface grooves for fission gas plenum

International Nuclear Information System (INIS)

Carter, T.J.; Jones, L.R.; Macici, N.; Miller, G.C.

1986-01-01

In the Canada deuterium uranium pressurized heavy water reactor, short (50-cm) Zircaloy-4 clad bundles are fueled on-power. Although internal void volume within the fuel rods is adequate for the present once-through natural uranium cycle, the authors have investigated methods for increasing the internal gas storage volume needed in high-power, high-burnup, experimental ceramic fuels. This present work sought to prove the methodology for design of gas storage volume within the fuel pellets - specifically the use of grooves pressed or machined into the relatively cool pellet/cladding interface. Preanalysis and design of pellet groove shape and volume was accomplished using the TRUMP heat transfer code. Postirradiation examination (PIE) was used to check the initial design and heat transfer assumptions. Fission gas release was found to be higher for the grooved pellet rods than for the comparison rods with hollow or unmodified pellets. This had been expected from the initial TRUMP thermal analyses. The ELESIM fuel modeling code was used to check in-reactor performance, but some modifications were necessary to accommodate the loss of heat transfer surface to the grooves. It was concluded that for plenum design purposes, circumferential pellet grooves could be adequately modeled by the codes TRUMP and ELESIM

Application of Artificial Neural Network to Predict the use of Runway at Juanda International Airport

Science.gov (United States)

Putra, J. C. P.; Safrilah

2017-06-01

Artificial neural network approaches are useful to solve many complicated problems. It solves a number of problems in various areas such as engineering, medicine, business, manufacturing, etc. This paper presents an application of artificial neural network to predict a runway capacity at Juanda International Airport. An artificial neural network model of backpropagation and multi-layer perceptron is adopted to this research to learning process of runway capacity at Juanda International Airport. The results indicate that the training data is successfully recognizing the certain pattern of runway use at Juanda International Airport. Whereas, testing data indicate vice versa. Finally, it can be concluded that the approach of uniformity data and network architecture is the critical part to determine the accuracy of prediction results.

V-groove SnO2 nanowire sensors: fabrication and Pt-nanoparticle decoration

International Nuclear Information System (INIS)

Sun, Gun-Joo; Choi, Sun-Woo; Jung, Sung-Hyun; Katoch, Akash; Kim, Sang Sub

2013-01-01

Networked SnO 2 nanowire sensors were achieved using the selective growth of SnO 2 nanowires and their tangling ability, particularly on on-chip V-groove structures, in an effort to overcome the disadvantages imposed on the conventional trench-structured SnO 2 nanowire sensors. The sensing performance of the V-groove-structured SnO 2 nanowire sensors was highly dependent on the geometrical dimension of the groove, being superior to those of their conventional trench-structured counterparts. Pt nanoparticles were decorated on the surface of the networked SnO 2 nanowires via γ-ray radiolysis to enhance the sensing performances of the V-groove sensors whose V-groove widths had been optimized. The V-groove-structured Pt-nanoparticle-decorated SnO 2 nanowire sensors exhibited outstanding and reliable sensing capabilities towards toluene and nitrogen dioxide gases, indicating their potential for use as a platform for chemical gas sensors. (paper)

Observations of secondary oscillations in thermal grain boundary grooves

International Nuclear Information System (INIS)

Sachenko, P.P.; Schneibel, J.H.; Zhang, W.

2004-01-01

Thermal grain boundary grooving by surface diffusion is accompanied not only by main maxima on either side of a groove, but also by secondary maxima and minima. We measure these oscillations in tungsten and give reasons why the observed secondary maxima and minima are larger than predicted

Numerical investigation of the effects of geometric parameters on transverse motion with slanted-groove micro-mixers

Energy Technology Data Exchange (ETDEWEB)

Baik, Seung Joo; Cho, Jae Yong; Choi, Se Bin; Lee, Joon Sang [School of Mechanical Engineering, Yonsei University, Seoul (Korea, Republic of)

2016-08-15

We investigated hydrodynamic phenomena inside several passive microfluidic mixers using a Lattice Boltzmann method (LBM) based on particle mesoscopic kinetic equations. Mixing processes were simulated in a Slanted grooved micro-mixer (SGM), a Staggered herringbone grooved micro-mixer (SHM), and a Bi-layered staggered herringbone grooved micro-mixer (BSHM). Then, the effects of six geometric mixer parameters (i.e., groove height to channel height ratio, groove width to groove pitch length ratio, groove pitch to groove height ratio, groove intersection angle, herringbone groove asymmetric ratio and bi-layered groove asymmetric ratio) on mixing were investigated using computed cross-flow velocity and helicity density distributions in the flow cross-section. We demonstrated that helicity density provides sufficient information to analyze micro helical motion within a micro-mixer, allowing for micro-mixer design optimization.

Grooved surface topography alters matrix-metalloproteinase production by human fibroblasts

Energy Technology Data Exchange (ETDEWEB)

Brydone, Alistair S; Dominic Meek, R M [Department of Orthopaedics, Southern General Hospital, 1345 Govan Road, Glasgow G51 4TF (United Kingdom); Dalby, Matthew J; Berry, Catherine C; McNamara, Laura E, E-mail: alibrydone@gmail.com [Centre for Cell Engineering, Joseph Black Building, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ (United Kingdom)

2011-06-15

Extracellular matrix (ECM) remodelling is an essential physiological process in which matrix-metalloproteinases (MMPs) have a key role. Manipulating the manner in which cells produce MMPs and ECMs may enable the creation of a desired tissue type, i.e. effect repair, or the prevention of tissue invasion (e.g. metastasis). The aim of this project was to determine if culturing fibroblasts on grooved topography altered collagen deposition or MMP production. Human fibroblasts were seeded on planar or grooved polycaprolactone substrates (grooves were 12.5 {mu}m wide with varying depths of 240 nm, 540 nm or 2300 nm). Cell behaviour and collagen production were studied using fluorescence microscopy and the spent culture medium was assessed using gel zymography to detect MMPs. Total collagen deposition was high on the 240 nm deep grooves, but decreased as the groove depth increased, i.e. as cell contact guidance decreased. There was an increase in gelatinase on the 2300 nm deep grooved topography and there was a difference in the temporal expression of MMP-3 observed on the planar surface compared to the 540 nm and 2300 nm topographies. These results show that topography can alter collagen and MMP production. A fuller understanding of these processes may permit the design of surfaces tailored to tissue regeneration e.g. tendon repair.

Grooved surface topography alters matrix-metalloproteinase production by human fibroblasts

International Nuclear Information System (INIS)

Brydone, Alistair S; Dominic Meek, R M; Dalby, Matthew J; Berry, Catherine C; McNamara, Laura E

2011-01-01

Extracellular matrix (ECM) remodelling is an essential physiological process in which matrix-metalloproteinases (MMPs) have a key role. Manipulating the manner in which cells produce MMPs and ECMs may enable the creation of a desired tissue type, i.e. effect repair, or the prevention of tissue invasion (e.g. metastasis). The aim of this project was to determine if culturing fibroblasts on grooved topography altered collagen deposition or MMP production. Human fibroblasts were seeded on planar or grooved polycaprolactone substrates (grooves were 12.5 μm wide with varying depths of 240 nm, 540 nm or 2300 nm). Cell behaviour and collagen production were studied using fluorescence microscopy and the spent culture medium was assessed using gel zymography to detect MMPs. Total collagen deposition was high on the 240 nm deep grooves, but decreased as the groove depth increased, i.e. as cell contact guidance decreased. There was an increase in gelatinase on the 2300 nm deep grooved topography and there was a difference in the temporal expression of MMP-3 observed on the planar surface compared to the 540 nm and 2300 nm topographies. These results show that topography can alter collagen and MMP production. A fuller understanding of these processes may permit the design of surfaces tailored to tissue regeneration e.g. tendon repair.

Novel scaffold design with multi-grooved PLA fibers

International Nuclear Information System (INIS)

Chung, Sangwon; King, Martin W; Gamcsik, Mike P

2011-01-01

A novel prototype nonwoven textile structure containing polylactide (PLA) multigrooved fibers has been proposed as a possible scaffold material for superior cell attachment and proliferation. Grooved cross-sectional fibers with larger surface area were obtained by a bi-component spinning system and the complete removal of the sacrificial component was confirmed by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and x-ray photon spectroscopy (XPS) analysis. These PLA nonwoven scaffolds containing the grooved fibers exhibited enhanced wettability, greater flexibility and tensile properties, and a larger surface area compared to a traditional PLA nonwoven fabric containing round fibers. To evaluate cellular attachment on the two types of PLA nonwoven scaffolds, NIH 3T3 fibroblasts were cultured for up to 12 days. It was evident that the initial cellular attachment was superior on the scaffold with grooved fibers, which was confirmed by MTT viability assay (p < 0.01) and SEM analysis. In the future, by modulating the size of the grooves on the fibers, such a scaffold material with a large surface area could serve as an alternative matrix for culturing different types of cells.

Syncopation, body-movement and pleasure in groove music.

Science.gov (United States)

Witek, Maria A G; Clarke, Eric F; Wallentin, Mikkel; Kringelbach, Morten L; Vuust, Peter

2014-01-01

Moving to music is an essential human pleasure particularly related to musical groove. Structurally, music associated with groove is often characterised by rhythmic complexity in the form of syncopation, frequently observed in musical styles such as funk, hip-hop and electronic dance music. Structural complexity has been related to positive affect in music more broadly, but the function of syncopation in eliciting pleasure and body-movement in groove is unknown. Here we report results from a web-based survey which investigated the relationship between syncopation and ratings of wanting to move and experienced pleasure. Participants heard funk drum-breaks with varying degrees of syncopation and audio entropy, and rated the extent to which the drum-breaks made them want to move and how much pleasure they experienced. While entropy was found to be a poor predictor of wanting to move and pleasure, the results showed that medium degrees of syncopation elicited the most desire to move and the most pleasure, particularly for participants who enjoy dancing to music. Hence, there is an inverted U-shaped relationship between syncopation, body-movement and pleasure, and syncopation seems to be an important structural factor in embodied and affective responses to groove.

Ion implantation planar in targets with semi-cylindrical grooves

International Nuclear Information System (INIS)

Filiz, Y.; Demokan, O.

2002-01-01

The experimental and numerical investigations suggest that the ion-matrix phase of the sheath evolution plays a crucial role in determining the ion flux to the target surfaces . It can easily be realized that conformal mapping of the target's surface by the sheath is questionable, or even inapplicable in the case of surfaces with fine irregularities or this continuities. The theoretical analysis of such cases is evidently quite complicated. On the other hand, most actual targets fall into this category, and hence, the understanding of the corresponding sheath behavior remains vital for accomplishing uniform implantation. The ion- matrix sheaths have been treated analytically by Conrad for planar, cylindrical and spherical targets successfully. Similar y, Sheridan and Zang et al. have investigated the ion matrix sheath in cylindrical bores, without and with axial electrodes, respectively. All these works assumed targets with infinite areas or length, Zeng et al. and Kwok et al. have started studying implantation into grooves, by carrying out simulations for the inner and outer races of bearings, which are modeled as semi- cylinders of infinite length. Finally, Demokan has presented the first analytic treatment of on matrix sheaths in two- dimensions, by considering targets with rectangular grooves of infinite length, representing a broad range of industrial items. In this work, ion-matrix sheath near infinite length are theoretically analysed. Understanding the sheath formation near such targets is essential for achieving successful ion implantation on the surfaces of a broad range of industrial products, including all types of bearings. The potential profiles both inside and outside the groove are derived and the consequent ion velocity higher plasma densities may improve the uniformity of implantation on the surfaces of such grooves. Furthermore, the sheath edge deformation due to the grooves, the variation of the angle of incidence on the surface of the groove

Labiogingival groove: A rare developmental tooth anomaly

Directory of Open Access Journals (Sweden)

Shiva Chauhan

2017-01-01

Full Text Available Labiogingival groove is a congenital morphologic dental anomaly, in which an infolding of the inner enamel epithelium and Hertwig's epithelial root sheath create a groove extending varying depth into root. Epithelial attachment can be breached by gingival irritation secondary to plaque accumulation creating a periodontal defect that spreads to the pulp causing primary periodontal/secondary endodontic. A 12-year-old boy reported with the complaint of painful tooth with pus discharge from labial gingival surface in the maxillary right lateral incisor for 4 months. Intraoral examination revealed bluish red gingiva with loss of contour in relation to maxillary right lateral incisor and purulent discharge in relation to it. A provisional diagnosis of localized gingival abscess in relation to maxillary right incisor (primary periodontic and secondary endodontic involvement was given, and required treatment was carried out. On exposure of the involved tooth, a labiogingival groove was noticed which could have been a contributing factor for the progression of the condition.

Modified Kelvin Equations for Capillary Condensation in Narrow and Wide Grooves

Science.gov (United States)

Malijevský, Alexandr; Parry, Andrew O.

2018-03-01

We consider the location and order of capillary condensation transitions occurring in deep grooves of width L and depth D . For walls that are completely wet by liquid (contact angle θ =0 ) the transition is continuous and its location is not sensitive to the depth of the groove. However, for walls that are partially wet by liquid, where the transition is first order, we show that the pressure at which it occurs is determined by a modified Kelvin equation characterized by an edge contact angle θE describing the shape of the meniscus formed at the top of the groove. The dependence of θE on the groove depth D relies, in turn, on whether corner menisci are formed at the bottom of the groove in the low density gaslike phase. While for macroscopically wide grooves these are always present when θ condensation transition is different depending on whether the contact angle is greater or less than a universal value θ*≈31 °. Our arguments are supported by detailed microscopic density functional theory calculations that show that the modified Kelvin equation remains highly accurate even when L and D are of the order of tens of molecular diameters.

Analysis of Runway Incursion Data

Science.gov (United States)

Green, Lawrence L.

2013-01-01

A statistical analysis of runway incursion (RI) events was conducted to ascertain relevance to the top ten challenges of the National Aeronautics and Space Administration Aviation Safety Program (AvSP). The information contained in the RI database was found to contain data that may be relevant to several of the AvSP top ten challenges. When combined with other data from the FAA documenting air traffic volume from calendar year 2000 through 2011, the structure of a predictive model emerges that can be used to forecast the frequency of RI events at various airports for various classes of aircraft and under various environmental conditions.

Resistance to minor groove binders.

Science.gov (United States)

Colmegna, Benedetta; Uboldi, Sarah; Erba, Eugenio; D'Incalci, Maurizio

2014-03-01

In this paper multiple resistance mechanisms to minor groove binders (MGBs) are overviewed. MGBs with antitumor properties are natural products or their derivatives and, as expected, they are all substrates of P-glycoprotein (P-gp). However, a moderate expression of P-gp does not appear to reduce the sensitivity to trabectedin, the only MGB so far approved for clinical use. Resistance to this drug is often related to transcriptional mechanisms and to DNA repair pathways, particularly defects in transcription-coupled nucleotide excision repair (TC-NER). Therefore tumors resistant to trabectedin may become hypersensitive to UV rays and other DNA damaging agents acting in the major groove, such as Platinum (Pt) complexes. If this is confirmed in clinic, that will provide the rationale to combine trabectedin sequentially with Pt derivates.

Aircraft performance in slippery runway conditions : a simulation study of the accuracy and limitations of real-time runway friction estimation based on airplane onboard data.

Science.gov (United States)

2015-04-01

Runway overrun accidents occurring during landings in slippery conditions continue to occur frequently worldwide. After a : number of specific landing overrun accidents in the U.S., the National Transportation Safety Board (NTSB) issued a safety : re...

Champagne Groove Lipectomy: A Safe Technique to Contour the Upper Abdomen in Abdominoplasty.

Science.gov (United States)

Brooks, Ron; Nguyen, Jonathan; Chowdhry, Saeed; Tutela, John Paul; Kelishadi, Sean; Yonick, David; Choo, Joshua; Wilhelmi, Bradon J

2017-01-01

Objective: Combined liposuction and abdominoplasty, or lipoabdominoplasty, is particularly helpful in sculpting a more aesthetically pleasing abdominal contour, particularly in the supraumbilical midline groove. This groove, coined the "champagne groove" by one of our patients, is a frequently sought-after attribute by patients. However, liposuction adds time and cost to an already costly abdominoplasty. We sought to create this groove without the addition of liposuction, utilizing what we call a champagne groove lipectomy. This study reports on our champagne groove lipectomy technique and compares our complication rates with those reported in the literature for standard abdominoplasty techniques. Methods: This is a retrospective review of a single surgeon's experience at our institution over a 6-year period (2007-2012). A total of 74 patients undergoing consecutive abdominoplasty were studied, all female nonsmokers. Two groups were recognized: 64 of 74 patients underwent abdominoplasty, partial belt lipectomy, and champagne groove lipectomy, while 10 of 74 patients underwent fleur-de-lis abdominoplasty without champagne groove lipectomy. Results: Overall, 10 of 74 patients (13.5%) suffered some type of complication, which compares favorably with reported rates in the literature. The majority of complications were related to delayed wound healing or superficial wound dehiscence. Among those patients who underwent champagne groove lipectomy, complications occurred in 6 of 64 patients (9.3%), versus 4 of 10 (40%) patients undergoing fleur-de-lis abdominoplasty. Conclusions: Champagne groove lipectomy is a cost-effective alternative to lipoabdominoplasty for achieving an aesthetically pleasing upper midline abdominal contour, with complication rates comparing favorably with those reported in the literature.

Functional Analysis for an Integrated Capability of Arrival/Departure/Surface Management with Tactical Runway Management

Science.gov (United States)

Phojanamongkolkij, Nipa; Okuniek, Nikolai; Lohr, Gary W.; Schaper, Meilin; Christoffels, Lothar; Latorella, Kara A.

2014-01-01

The runway is a critical resource of any air transport system. It is used for arrivals, departures, and for taxiing aircraft and is universally acknowledged as a constraining factor to capacity for both surface and airspace operations. It follows that investigation of the effective use of runways, both in terms of selection and assignment as well as the timing and sequencing of the traffic is paramount to the efficient traffic flows. Both the German Aerospace Center (DLR) and NASA have developed concepts and tools to improve atomic aspects of coordinated arrival/departure/surface management operations and runway configuration management. In December 2012, NASA entered into a Collaborative Agreement with DLR. Four collaborative work areas were identified, one of which is called "Runway Management." As part of collaborative research in the "Runway Management" area, which is conducted with the DLR Institute of Flight Guidance, located in Braunschweig, the goal is to develop an integrated system comprised of the three DLR tools - arrival, departure, and surface management (collectively referred to as A/D/S-MAN) - and NASA's tactical runway configuration management (TRCM) tool. To achieve this goal, it is critical to prepare a concept of operations (ConOps) detailing how the NASA runway management and DLR arrival, departure, and surface management tools will function together to the benefit of each. To assist with the preparation of the ConOps, the integrated NASA and DLR tools are assessed through a functional analysis method described in this report. The report first provides the highlevel operational environments for air traffic management (ATM) in Germany and in the U.S., and the descriptions of the DLR's A/D/S-MAN and NASA's TRCM tools at the level of details necessary to compliment the purpose of the study. Functional analyses of each tool and a completed functional analysis of an integrated system design are presented next in the report. Future efforts to fully

Documentation of roller-bearing effect on butterfly inspired grooves

Science.gov (United States)

Gautam, Sashank; Lang, Amy

2017-11-01

Butterfly wings are covered with scales in a roof shingle pattern which align together to form grooves. The increase or decrease of laminar friction drag depends on the flow orientation to the scales. Flow in the longitudinal direction to the grooves encounters increased surface area which increases the friction drag. However, in the transverse direction, for low Re laminar flow, a single vortex is formed inside each groove and is predicted to remain stable due to the very low Re of the flow in each cavity. These embedded vortices act as roller bearings to the flow above, such that the fluid from the outer boundary layer does not mix with fluid inside the cavities. This leads to a reduction of skin friction drag when compared to a smooth surface. When the cavity flow Re is increased beyond a critical point, the vortex becomes unstable and the low-momentum fluid in the grooves mixes with the outer boundary layer flow, increasing the drag. The objective of this experiment is to determine the critical Re where the embedded vortex transitions from a stable to an unstable state using DPIV. Subsequently, for steady vortex conditions, a comparison of skin friction drag between the grooved and flat plate can show that the butterfly scaled surface can result in sub-laminar friction drag. The National Science Foundation (Grant No. 1335848).

Statistical Decision Support Tools for System-Oriented Runway Management, Phase II

Data.gov (United States)

National Aeronautics and Space Administration — The feasibility of developing a statistical decision support system for traffic flow management in the terminal area and runway load balancing was demonstrated in...

Formation Mechanisms for Spur and Groove Features on Fringing Reefs

Science.gov (United States)

Bramante, J. F.; Ashton, A. D.; Perron, J. T.

2016-12-01

Spur and groove systems (SAGs) are ubiquitous morphological features found on fore-reef slopes globally. SAGs consist of parallel, roughly shore-normal ridges of actively growing coral and coralline algae (spurs) separated by offshore-sloping depressions typically carpeted by a veneer of sediment (grooves). Although anecdotal observations and recent statistical analyses have reported correlations between wave exposure and the distribution of SAGs on fore-reef slopes, the physical mechanisms driving SAG formation remain poorly understood. For example, there remains significant debate regarding the importance of coral growth versus bed erosion for SAG formation. Here we investigate a hypothesis that SAG formation is controlled by feedbacks between sediment production and diffusion and coral growth. Using linear stability analysis, we find that sediment production, coral growth, and the feedbacks between them are unable to produce stable periodic structures without a sediment sink. However, if incipient grooves act as conduits for sediment transport offshore, a positive feedback can develop as the groove bed erodes through wave-driven abrasion during offshore transport. Eventually a negative feedback slows groove deepening when the groove bed is armored by sediment, and the groove bed relaxes to a sediment-veneered equilibrium profile analogous to sediment-rich shorefaces. To test this hypothesis, we apply a numerical model that incorporates coral growth and sediment production, sediment diffusion, non-linear wave-driven abrasion, and sediment advection offshore. This model produces the periodic, linear features characteristic of SAG morphology. The relative magnitude of growth, production, diffusion, abrasion, and advection rates affect periodic spacing or wavelength of the modeled SAGs. Finally, we evaluate the ability of the model to replicate geographical variability in SAG characteristics using previously published datasets and reanalysis wave data.

Combined endodontic-periodontic treatment of a palatal groove: a case report.

Science.gov (United States)

Schwartz, Scott A; Koch, Michael A; Deas, David E; Powell, Charles A

2006-06-01

The palatal groove is a developmental anomaly that predisposes the tooth involved to a severe periodontal defect. When further complicated by pulp necrosis, these grooves often present a diagnostic and treatment planning challenge that requires an interdisciplinary treatment approach. This case report describes the successful collaborative management of a maxillary lateral incisor with an extensive palatal groove using a combination of nonsurgical endodontic therapy, odontoplasty, and periodontal regenerative techniques.

Graphene Plasmons in Triangular Wedges and Grooves

DEFF Research Database (Denmark)

Gonçalves, P. A. D.; Dias, E. J. C.; Xiao, Sanshui

2016-01-01

and tunability of graphene plasmons guided along the apex of a graphene-covered dielectric wedge or groove. In particular, we present a quasi-analytic model to describe the plasmonic eigenmodes in such a system, including the complete determination of their spectrum and corresponding induced potential...... and electric-field distributions. We have found that the dispersion of wedge/groove graphene plasmons follows the same functional dependence as their flat-graphene plasmon counterparts, but now scaled by a (purely) geometric factor in which all the information about the system’s geometry is contained. We...

Syncopation, body-movement and pleasure in groove music.

Directory of Open Access Journals (Sweden)

Maria A G Witek

Full Text Available Moving to music is an essential human pleasure particularly related to musical groove. Structurally, music associated with groove is often characterised by rhythmic complexity in the form of syncopation, frequently observed in musical styles such as funk, hip-hop and electronic dance music. Structural complexity has been related to positive affect in music more broadly, but the function of syncopation in eliciting pleasure and body-movement in groove is unknown. Here we report results from a web-based survey which investigated the relationship between syncopation and ratings of wanting to move and experienced pleasure. Participants heard funk drum-breaks with varying degrees of syncopation and audio entropy, and rated the extent to which the drum-breaks made them want to move and how much pleasure they experienced. While entropy was found to be a poor predictor of wanting to move and pleasure, the results showed that medium degrees of syncopation elicited the most desire to move and the most pleasure, particularly for participants who enjoy dancing to music. Hence, there is an inverted U-shaped relationship between syncopation, body-movement and pleasure, and syncopation seems to be an important structural factor in embodied and affective responses to groove.

Effect of heat treatment on the grooving corrosion resistance of ERW pipes

International Nuclear Information System (INIS)

Lee, Jong Kwon; Lee, Jae Young; Lim, Soo Hyun; Park, Ji Hwan; Seo, Bo Min; Kim, Seon Hwa

2002-01-01

The v-sharp grooving corrosion of ERW(electrical resistance welding) steel pipes limited their wide application in the industry in spite of their high productivity and efficiency. The grooving corrosion is caused mainly by the different microstructures between the matrix and weld that is formed during the rapid heating and cooling cycle in welding. By this localized corrosion reaction of pipes, it evolves economic problems such as the early damage of industrial facilities and pipe lines of apartment, and water pollution. Even though the diminishing of sulfur content is most effective to decrease the susceptibility of grooving corrosion, it requires costly process. In this study, improvement of grooving corrosion resistance was pursuited by post weld heat treatment in the temperature range between 650 .deg. C and 950 .deg. C. Also, the effect of heat input in the welding was investigated. By employing chromnoamperometry and potentiodynamic experiment, the corrosion rate and grooving corrosion index(α) were obtained. It was found that heat treatment could improve the grooving corrosion resistance. Among them, the heat treated at 900 .deg. C and 950 .deg. C had excellent grooving corrosion resistance. The index of heat treated specimen at 900 .deg. C and 950 .deg. C were 1.0, 1.2, respectively, which are almost immune to the grooving corrosion. Potential difference after the heat treatment, between base and weld metal was decreased considerably. While the as-received one measured 61∼71 mV, that of the 900 .deg. C heat treated steel pipe measured only 10mV. The results were explained and discussed

Design, construction and validation of the UST-1 modular stellarator

Energy Technology Data Exchange (ETDEWEB)

Queral, V., E-mail: vicentemanuel.queral@ciemat.es

2016-11-15

Highlights: • A small and simple low cost two period modular stellarator is reviewed. • It is defined as a monolithic circular surface torus with carved grooves. • The grooves are accurately mechanised by a new toroidal milling machine. • A very simple e-beam field mapping system has been built and utilized. - Abstract: Stellarator advancement is hindered, among others, by the requirement of geometric complexity at high accuracy and the still scarce universities and research centres following the stellarator line. In this framework, the objectives of the small UST-1 stellarator development were to: (i) explore and test the performance of one possible accurate construction method for stellarators (ii) encourage universities and small fusion research centres to build simple and economical stellarators (iii) educative purpose. Therefore, UST-1 was properly designed to be easily built by a milling machine working on toroidal coordinates, being the winding surface circular poloidally and toroidally. The coil frame is a sole monolithic toroidal thick surface equipped with grooves mechanised by the toroidal milling machine. Only one double pancake is wound in each groove so as to compress the conductor on the laterals of the groove in order to speed up and simplify the winding process. The physics design, the conceptual engineering design and the construction process of UST-1 is presented. The toroidal milling machine is described. The e-beam field line mapping experiments carried out to validate the resulting magnetic configuration are reported. The developed construction method has been proved for the small UST-1 stellarator. Small stellarators are valuable for quick tests of diagnostics, educative purposes, assessment of new confinement concepts, turbulence studies and other applications.

Design, construction and validation of the UST-1 modular stellarator

International Nuclear Information System (INIS)

Queral, V.

2016-01-01

Highlights: • A small and simple low cost two period modular stellarator is reviewed. • It is defined as a monolithic circular surface torus with carved grooves. • The grooves are accurately mechanised by a new toroidal milling machine. • A very simple e-beam field mapping system has been built and utilized. - Abstract: Stellarator advancement is hindered, among others, by the requirement of geometric complexity at high accuracy and the still scarce universities and research centres following the stellarator line. In this framework, the objectives of the small UST-1 stellarator development were to: (i) explore and test the performance of one possible accurate construction method for stellarators (ii) encourage universities and small fusion research centres to build simple and economical stellarators (iii) educative purpose. Therefore, UST-1 was properly designed to be easily built by a milling machine working on toroidal coordinates, being the winding surface circular poloidally and toroidally. The coil frame is a sole monolithic toroidal thick surface equipped with grooves mechanised by the toroidal milling machine. Only one double pancake is wound in each groove so as to compress the conductor on the laterals of the groove in order to speed up and simplify the winding process. The physics design, the conceptual engineering design and the construction process of UST-1 is presented. The toroidal milling machine is described. The e-beam field line mapping experiments carried out to validate the resulting magnetic configuration are reported. The developed construction method has been proved for the small UST-1 stellarator. Small stellarators are valuable for quick tests of diagnostics, educative purposes, assessment of new confinement concepts, turbulence studies and other applications.

Study of mastoid canals and grooves in north karnataka human skulls.

Science.gov (United States)

Hadimani, Gavishiddappa Andanappa; Bagoji, Ishwar Basavantappa

2013-08-01

This study was undertaken to observe the frequency of mastoid canals and grooves in north Karnataka dry human skulls. 100 dry human skulls of unknown age and sex from the department of Anatomy were selected and observed for the present study. The mastoid regions of dry skulls were observed for the presence of mastoid canals and grooves, if any. A metallic wire was passed through the canal for its confirmation and then the length was measured. The Mastoid canals were present in 53% of the total 100 skulls observed either bilaterally or unilaterally. Mastoid grooves were present in 18% of the total skulls (100) observed. Double mastoid canal was found in 01% of total skull studied and both Mastoid canals & Mastoid grooves together were present in 02% of the total skulls (100) observed. The knowledge of mastoid canals and grooves is very important for otolaryngologists and neurosurgeons. Because they contain an arterial branch of occipital artery with its accompanying vein which is liable to injury resulting into severe bleeding.

Palatal radicular groove: Clinical implications of early diagnosis and surgical sealing

Directory of Open Access Journals (Sweden)

P Corrêa-Faria

2011-01-01

Full Text Available Palatal radicular groove is a discreet alteration in tooth morphology, characterized by an invagination that begins near the cingulum of the tooth and moves in an apical direction. Clinically, palatal radicular groove may be associated with periodontal and/or endodontic problems. This paper describes a clinical case of a young patient with palatal radicular groove with no signs of periodontal disease or endodontic impairment. An early diagnosis was made and treatment consisted of surgical sealing of the defect. After a 2-year period, reexaminations demonstrated adequate hygiene, maintenance of tooth vitality and periodontal health. The early diagnosis and sealing of the groove observed surgically made the root surface smooth, avoiding subgingival bacterial plaque buildup, and preventing possible periodontal and/or pulp impairment stemming from the defect.

Study of a Tricarbide Grooved Ring Fuel Element for Nuclear Thermal Propulsion

Science.gov (United States)

Taylor, Brian; Emrich, Bill; Tucker, Dennis; Barnes, Marvin; Donders, Nicolas; Benensky, Kelsa

2018-01-01

Deep space exploration, especially that of Mars, is on the horizon as the next big challenge for space exploration. Nuclear propulsion, through which high thrust and efficiency can be achieved, is a promising option for decreasing the cost and logistics of such a mission. Work on nuclear thermal engines goes back to the days of the NERVA program. Currently, nuclear thermal propulsion is under development again in various forms to provide a superior propulsion system for deep space exploration. The authors have been working to develop a concept nuclear thermal engine that uses a grooved ring fuel element as an alternative to the traditional hexagonal rod design. The authors are also studying the use of carbide fuels. The concept was developed in order to increase surface area and heat transfer to the propellant. The use of carbides would also raise the operating temperature of the reactor. It is hoped that this could lead to a higher thrust to weight nuclear thermal engine. This paper describes the modeling of neutronics, heat transfer, and fluid dynamics of this alternative nuclear fuel element geometry. Fabrication experiments of grooved rings from carbide refractory metals are also presented along with material characterization and interactions with a hot hydrogen environment. Results of experiments and associated analysis are discussed. The authors demonstrated success in reaching desired densities with some success in material distribution and reaching a solid solution. Future work is needed to improve distribution of material, minimize oxidation during the milling process, and define a fabrication process that will serve for constructing grooved ring fuel rods for large system tests.

Effects of groove shape of notch on the flow characteristics of spool valve

International Nuclear Information System (INIS)

Ye, Yi; Yin, Chen-Bo; Li, Xing-Dong; Zhou, Wei-jin; Yuan, Feng-feng

2014-01-01

Highlights: • Flow characteristics of notches are studied using CFD simulation and experiment. • Test data is fitted by least square method to analyze discharge coefficient. • The stable value of discharge coefficient is deduced. • Effects of groove shape on steady flow force and throttling stiffness are performed. • The groove shape has significant effects on the flow characteristics. - Abstract: The grooves of notches of hydraulic spool valves are usually designed into various shapes for their desired flow characteristics. The aim of this paper is to clarify the effects of the groove shape on the flow characteristics through computational fluid dynamics (CFD) and experimental investigations. The RNG k–ε turbulence model is used to simulate the pressure distributions of the flow fields inside three notches with their corresponding typical structural grooves in order to analyze the changes of restricted locations along with the openings and, furthermore, to calculate the flow areas of the notches. The accuracy of the employed model is demonstrated by comparing the computational results with the experimental data. Additionally, the flow rate vs. pressure drop data obtained from the experiment is fitted by least square method. On this basis, the discharge coefficient as a function of groove geometry, flow condition, fitting coefficients and its stable value is deduced, proving to be quite consistent with the experimental result. Thanks to the jet flow angles estimated by CFD simulation, the steady flow forces are calculated, which show good agreement with the experimental results except for some small differences. Finally, the throttling stiffness of the three notches is investigated, with that of divergent U-shape groove falls between spheroid-shape groove and triangle-shape groove. Similar results are found for steady flow force. The results indicate that the groove shape has significant effects on the flow characteristics (flow area, discharge

Gap and channeled plasmons in tapered grooves: a review

DEFF Research Database (Denmark)

Smith, C. L. C.; Stenger, Nicolas; Kristensen, Anders

2015-01-01

Tapered metallic grooves have been shown to support plasmons - electromagnetically coupled oscillations of free electrons at metal-dielectric interfaces - across a variety of configurations and V-like profiles. Such plasmons may be divided into two categories: gap-surface plasmons (GSPs) that are......Tapered metallic grooves have been shown to support plasmons - electromagnetically coupled oscillations of free electrons at metal-dielectric interfaces - across a variety of configurations and V-like profiles. Such plasmons may be divided into two categories: gap-surface plasmons (GSPs...... platform to explore the fundamental science of plasmon excitations and their interactions. In this Review, we provide a research status update of plasmons in tapered grooves, starting with a presentation of the theory and important features of GSPs and CPPs, and follow with an overview of the broad range...

Dispersion characteristics of planar grating with arbitrary grooves for terahertz Smith-Purcell radiation

International Nuclear Information System (INIS)

Cao, Miaomiao; Li, Ke; Liu, Wenxin; Wang, Yong

2015-01-01

In this paper, a novel method of getting the dispersion relations in planar grating with arbitrary grooves for terahertz Smith-Purcell radiation is investigated analytically. The continuous profile of the groove is approximately replaced by a series of rectangular steps. By making use of field matches method and the continuity of transverse admittance, the universal dispersion equation for grating with arbitrarily shaped grooves is derived. By solving the dispersion equation in presence of electron beam, the growth rate is obtained directly and the dependence on beam parameters is analyzed. Comparisons of the dispersion characteristics among some special groove shapes have been made by numerical calculation. The results show that the rectangular-step approximation method provides a novel approach to obtain the universal dispersion relation for grating with arbitrary grooves for Smith-Purcell radiation

Evaluasi Kekuatan Perkerasan Sisi Udara (Runway,Taxiway,Apron Bandara Juanda Dengan Metode Perbandingan ACN-PCN

Directory of Open Access Journals (Sweden)

R. Haryo Triharso Seno

2015-03-01

Full Text Available Fasilitas sisi udara merupakan fasilitas pergerakan pesawat. Fasilitas ini harus memenuhi kekuatan struktur untuk melayani pergerakan pesawat-pesawat yang beroperasi sesuai dengan perencanaan. Tujuan dari penyusunan makalah ini adalah untuk menganalisis apakah perkerasan fasilitas sisi udara di Bandar Udara Juanda saat ini sudah memenuhi batas PCN yang dipersyaratkan atau belum. Analisis dilakukan dengan cara mengevaluasi kekuatan perkerasan runway, taxiway, dan apron eksisting menggunakan metode perbandingan PCN–ACN yang didapat dari pabrik pembuat pesawat, perhitungan dengan software COMFAA dan perhitungan dari Canadian Department of Transportation. Data yang digunakan adalah data pergerakan pesawat termasuk jumlah pergerakan tahunan dan tipe pesawat. Data kekuatan perkerasan sisi udara diperlukan untuk proses analisis. Hasil dari evaluasi menunjukkan B773 memiliki nilai ACN yang melebihi nilai PCN sebesar 50% untuk apron dan 25% untuk runway/taxiway. Besar kelebihan nilai ACN ini tidak mempengaruhi kekuatan struktural karena frekuensi pergerakan yang hanya 45 pergerakan per tahun. Dampak lain adalah pada fungsional perkerasan yang menunjukkan berkurangnya kekesatan runway dari hasil sand patch test.

Long term performance of the reef runway at Honolulu International Airport

CSIR Research Space (South Africa)

Magoon, OT

2007-07-01

Full Text Available Completed in 1977, the Reef Runway embankment at Honolulu International Airport was created by placing and compacting millions of cubic meters of dredged coral fill material over an existing coral reef. The wave protection structure on the deeper...

Runway Detection From Map, Video and Aircraft Navigational Data

Science.gov (United States)

2016-03-01

3 Figure 4. Pinhole Camera Model to Project 3D Coordinates onto 2D...xii THIS PAGE INTENTIONALLY LEFT BLANK xiii LIST OF ACRONYMS AND ABBREVIATIONS 2D Two-dimensional 3D Three-dimensional HFOV Horizontal field of...algorithm [2], which selects runway-useful features, such as image intensity and gradient or Zernike Moments, and extracts them on a set of 57

Flow characterization in periodic microchannels containing asymmetric grooves

Energy Technology Data Exchange (ETDEWEB)

Osorio-Nesme, A; Delgado, A, E-mail: anuhar.nesme@fau.de [Institute of Fluid Mechanics, Friedrich-Alexander Erlangen-Nuremberg University, Cauerstrasse 4, D-91058 Erlangen (Germany)

2017-10-15

Characterization of two-dimensional flows in microchannels with anisotropic periodic grooves is numerically carried out by using the lattice Boltzmann method. Periodically placed microstructures, consisting of novel nozzle-diffuser-like grooves are deliberately designed to introduce a flow-direction dependent resistance. Simulations were conducted for a low-to-moderate Reynolds number in the laminar-transition flow regime. Different channel geometries, defined by the half-angle ϕ of the periodic grooves are considered. The influence of the half-angle on both the flow field and the onset of oscillatory flow regime at different driving body forces is analyzed. At a low Reynolds number, the flow is observed stationary and fully reversible, regardless of the groove geometry. In this regime, higher Reynolds numbers were observed when the geometry acts as a diffuser (negative flow) than as a nozzle (positive flow) for a given driving body force. At sufficiently high Reynolds number the flow turns from a steady state to a time-dependent oscillatory regime through a Hopf bifurcation. Successive flow bifurcations lead the flow structure from a periodic regime to a quasi-chaotic regime with three-dimensional structures. The onset of unsteady flow occurs earlier for positive flows and geometries with small half-angles. For higher driving forces, there is a reduction in the volume flow rate due to the advected material in the transversal direction, causing consequently a decrease in the Reynolds number. (paper)

Individual Differences in Beat Perception Affect Gait Responses to Low- and High-Groove Music

Science.gov (United States)

Leow, Li-Ann; Parrott, Taylor; Grahn, Jessica A.

2014-01-01

Slowed gait in patients with Parkinson’s disease (PD) can be improved when patients synchronize footsteps to isochronous metronome cues, but limited retention of such improvements suggest that permanent cueing regimes are needed for long-term improvements. If so, music might make permanent cueing regimes more pleasant, improving adherence; however, music cueing requires patients to synchronize movements to the “beat,” which might be difficult for patients with PD who tend to show weak beat perception. One solution may be to use high-groove music, which has high beat salience that may facilitate synchronization, and affective properties, which may improve motivation to move. As a first step to understanding how beat perception affects gait in complex neurological disorders, we examined how beat perception ability affected gait in neurotypical adults. Synchronization performance and gait parameters were assessed as healthy young adults with strong or weak beat perception synchronized to low-groove music, high-groove music, and metronome cues. High-groove music was predicted to elicit better synchronization than low-groove music, due to its higher beat salience. Two musical tempi, or rates, were used: (1) preferred tempo: beat rate matched to preferred step rate and (2) faster tempo: beat rate adjusted to 22.5% faster than preferred step rate. For both strong and weak beat-perceivers, synchronization performance was best with metronome cues, followed by high-groove music, and worst with low-groove music. In addition, high-groove music elicited longer and faster steps than low-groove music, both at preferred tempo and at faster tempo. Low-groove music was particularly detrimental to gait in weak beat-perceivers, who showed slower and shorter steps compared to uncued walking. The findings show that individual differences in beat perception affect gait when synchronizing footsteps to music, and have implications for using music in gait rehabilitation. PMID:25374521

Individual differences in beat perception affect gait responses to low- and high-groove music.

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Li-Ann eLeow

2014-10-01

Full Text Available Slowed gait in Parkinson’s disease (PD patients can be improved when patients synchronize footsteps to isochronous metronome cues, but limited retention of such improvements suggest that permanent cueing regimes are needed for long-term improvements. If so, music might make permanent cueing regimes more pleasant, improving adherence; however, music cueing requires patients to synchronize movements to the beat, which might be difficult for PD patients who tend to show weak beat perception. One solution may be to use high groove music, which has high beat salience that may facilitate synchronization, and affective properties which may improve motivation to move. As a first step in understanding how beat perception affects gait in complex neurological disorders, we examined how beat perception ability affected gait in neurotypical adults. Synchronization performance and gait parameters were assessed as healthy young adults with strong or weak beat perception synchronized to low groove music, high groove music, and metronome cues. High groove music was predicted to elicit better synchronization than low groove music, due to its higher beat salience. Two musical tempi, or rates, were used: (1 preferred tempo: beat rate matched to preferred step rate and (2 faster tempo: beat rate adjusted to 22.5% faster than preferred step rate. For both strong and weak beat-perceivers, synchronization performance was best with metronome cues, followed by high groove music, and worst with low groove music. In addition, high groove music elicited longer and faster steps than low groove music, both at preferred tempo and at faster tempo. Low groove music was particularly detrimental to gait in weak beat-perceivers, who showed slower and shorter steps compared to uncued walking. The findings show that individual differences in beat perception affect gait when synchronizing footsteps to music, and have implications for using music in gait rehabilitation.

Management of endodontic-periodontic lesion of a maxillary lateral incisor with palatoradicular groove

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Jayshree Ramakrishna Vishwas

2014-01-01

Full Text Available Presence of palatal radicular grooves are considered to be an important contributing factor to the development of localized periodontitis, as it favored the accumulation and proliferation of bacterial plaque deep into the periodontium. Pulp involvement could result due to the introduction of bacterial toxins through channels that existed between the root canal system and the groove. Early diagnosis, elimination of inflammation and correction of anatomic complications are the key to a favorable outcome for managing palatoradicular groove. Present report describes successful management with an interdisciplinary approach of maxillary lateral incisor with combined endodontic periodontic lesion associated with palatoradicular groove.

Correcting groove error in gratings ruled on a 500-mm ruling engine using interferometric control.

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Mi, Xiaotao; Yu, Haili; Yu, Hongzhu; Zhang, Shanwen; Li, Xiaotian; Yao, Xuefeng; Qi, Xiangdong; Bayinhedhig; Wan, Qiuhua

2017-07-20

Groove error is one of the most important factors affecting grating quality and spectral performance. To reduce groove error, we propose a new ruling-tool carriage system based on aerostatic guideways. We design a new blank carriage system with double piezoelectric actuators. We also propose a completely closed-loop servo-control system with a new optical measurement system that can control the position of the diamond relative to the blank. To evaluate our proposed methods, we produced several gratings, including an echelle grating with 79  grooves/mm, a grating with 768  grooves/mm, and a high-density grating with 6000  grooves/mm. The results show that our methods effectively reduce groove error in ruled gratings.

Laser melting of groove defect repair on high thermal conductivity steel (HTCS-150)

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Norhafzan, B.; Aqida, S. N.; Fazliana, F.; Reza, M. S.; Ismail, I.; Khairil, C. M.

2018-02-01

This paper presents laser melting repair of groove defect on HTCS-150 surface using Nd:YAG laser system. Laser melting process was conducted using JK300HPS Nd:YAG twin lamp laser source with 1064 nm wavelength and pulsed mode. The parameters are pulse repetition frequency (PRF) that is set from 70 to 100 Hz, average power ( P A) of 50-70 W, and laser spot size of 0.7 mm. HTCS-150 samples were prepared with groove dimension of 0.3 mm width and depths of 0.5 mm using EDM wire cut. Groove defect repaired using laser melting process on groove surface area with various parameters' process. The melted surface within the groove was characterized for subsurface hardness profile, roughness, phase identification, chemical composition, and metallographic study. The roughness analysis indicates high PRF at large spot size caused high surface roughness and low surface hardness. Grain refinement of repaired layer was analyzed within the groove as a result of rapid heating and cooling. The hardness properties of modified HTCS inside the groove and the bulk surface increased two times from as received HTCS due to grain refinement which is in agreement with Hall-Petch equation. These findings are significant to parameter design of die repair for optimum surface integrity and potential for repairing crack depth and width of less than 0.5 and 0.3 mm, respectively.

Microcirculation within Grooved Substrates regulates Cell Positioning and Cell Docking inside Microfluidic Channels

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Manbachi, Amir; Shrivastava, Shamit; Cioffi, Margherita; Chung, Bong Geun; Moretti, Matteo; Demirci, Utkan; Yliperttula, Marjo; Khademhosseini, Ali

2009-01-01

Immobilization of cells inside microfluidic devices is a promising approach for enabling studies related to drug screening and cell biology. Despite extensive studies in using grooved substrates for immobilizing cells inside channels, a systematic study of the effects of various parameters that influence cell docking and retention within grooved substrates has not been performed. We demonstrate using computational simulations that the fluid dynamic environment within microgrooves significantly varies with groove width, generating micro-circulation areas in smaller microgrooves. Wall shear stress simulation predicted that shear stresses were in opposite direction in smaller grooves (25 and 50 μm wide) in comparison to those in wider grooves (75 and 100 μm wide). To validate the simulations, cells were seeded within microfluidic devices, where microgrooves of different widths were aligned perpendicularly to the direction of the flow. Experimental results showed that, as predicted, the inversion of the local direction of shear stress within the smaller grooves resulted in alignment of cells on two opposite sides of the grooves under the same flow conditions. Also, the amplitude of shear stress within microgrooved channels significantly influenced cell retainment in the channels. Therefore, our studies suggest that microscale shear stresses greatly influence cellular docking, immobilization, and retention in fluidic systems and should be considered for the design of cell-based microdevices. PMID:18432345

Grooving of grain boundaries in multicrystalline silicon: Effect on solar cell performance

International Nuclear Information System (INIS)

Dimassi, W.; Bouaicha, M.; Nouri, H.; Boujmil, M.F.; Ben Nasrallah, S.; Bessais, B.

2006-01-01

In this work, we investigate the effect of grooving of grain boundaries (GB) in multicrystalline silicon using chemical etching in HF/HNO 3 solutions. The grain boundaries were grooved in order to reduce the area of these highly recombining regions. Using optimized conditions, grooved GBs enable deep phosphorus diffusion and deep metallic contacts. As a result, the internal quantum efficiency (IQE), and the I-V characteristics under the dark and AM1.5 illumination were improved. It was also observed a reduction of the GB recombination velocity, which was deduced from light-beam-induced-current (LBIC) measurements. Such grooving in multicrystalline silicon enables passivation of GB-related defects. These results are discussed and compared to solar cells based on untreated multicrystalline silicon wafers

From the Bandstand to the Classroom: Thinking and Playing Grooves

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Baxter, Marsha; Santantasio, Christopher

2012-01-01

In this article, narratives of a salsa concert and a lesson with a Native American flute performer provide openings for exploring grooves and their application in the music classroom. The term "groove" is examined, along with some non-Western ideas about time as represented in the music of the West African Kpelle people. A sixth-grade…

The complex radicular groove: interdisciplinary management with mineral trioxide aggregate and bone substitute.

Science.gov (United States)

Narmatha, V J; Thakur, Sophia; Shetty, Sheetal; Bali, Praveen Kumar

2014-11-01

This article is a case report of the successful interdisciplinary management of a maxillary lateral incisor with a deep palatogingival groove. The tooth presented with severe periodontal destruction owing to the deep extension of the groove up to the root apex. The groove was meticulously diagnosed and treated by endodontic and subsequent periodontal surgery leading to complete resolution of the pathological process.

[Developmental radicular groove as a cause of endodontic failure].

Science.gov (United States)

Fabra Campos, H; Millet Part, J

1989-01-01

A clinical case of apical injury on an upper lateral incisor with endodontical and surgical failures in its treatment is presented. Extraction of the incisor and its study at the stereoscopic microscope showed the existence of a developmental groove running from the cingulum to the end of the root, establishing a communication between the crevice and the apical part of the tooth. Bacterial infection through the groove could provide an explanation for treatment failure.

An overview of the joint FAA/NASA aircraft/ground runway friction program

Science.gov (United States)

Yager, Thomas J.

1989-01-01

There is a need for information on runways which may become slippery due to various forms and types of contaminants. Experience has shown that since the beginning of all weather aircraft operations, there have been landing and aborted takeoff incidents and/or accidents each year where aircraft have either run off the end or veered off the shoulder of low friction runways. NASA Langley's Landing and Impact Dynamics Branch is involved in several research programs directed towards obtaining a better understanding of how different tire properties interact with varying pavement surface characteristics to produce acceptable performance for aircraft ground handling requirements. One such effort, which was jointly supported by not only NASA and the FAA but by several aviation industry groups including the Flight Safety Foundation, is described.

Schwann cell interactions with polymer films are affected by groove geometry and film hydrophilicity

International Nuclear Information System (INIS)

Mobasseri, S A; Downes, S; Terenghi, G

2014-01-01

We have developed a biodegradable polymer scaffold made of a polycaprolactone/polylactic acid (PCL/PLA) film. Surface properties such as topography and chemistry have a vital influence on cell–material interactions. Surface modifications of PCL/PLA films were performed using topographical cues and UV–ozone treatment to improve Schwann cell organisation and behaviour. Schwann cell attachment, alignment and proliferation were evaluated on the grooved UV–ozone treated and non-treated films. Solvent casting of the polymer solution on patterned silicon substrates resulted in films with different groove shapes: V (V), sloped (SL) and square (SQ) shapes. Pitted films, with no grooves, were prepared as a negative control. The UV–ozone treatment was performed to increase hydrophilicity. The process specifications for UV–ozone treatment were evaluated and 5 min radiation time and 6 cm distance to the UV source were suggested as the optimal practise. When cultured on grooved films, Schwann cells elongated on the V and SL shape grooves without crossing over, and grew in the direction of the grooves. However, there was less elongation with more crossing over on the SQ shape grooves. The maximum cell length (511 μm) was observed on the treated V-grooved films. The cells cultured on pitted UV–ozone treated surfaces showed random arrangements with no increase in length. We have demonstrated that the synergic effects of physical cues combined with UV–ozone treatment have the potential to enhance Schwann cell morphology and alignment. (paper)

Treatment of a Developmental Groove and Supernumerary Root Using Guided Tissue Regeneration Technique

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Zahra Alizadeh Tabari

2016-01-01

Full Text Available Introduction. The radicular groove is a developmental groove which is usually found on the palatal or lateral aspects of the maxillary incisor teeth. The present case is a maxillary lateral incisor with a small second root and a deep radicular groove. The developmental groove caused a combined periodontal-endodontic lesion. Methods. Case was managed using a combined treatment procedure involving nonsurgical root canal therapy and surgical periodontal treatment. After completion of root canal treatment, guided tissue regeneration (GTR was carried out using decalcified freeze dried bone allograft (DFDBA and a bioabsorbable collagenous membrane. Tooth also was splinted for two months. Results. After 12 months the tooth was asymptomatic. The periapical radiolucency disappeared and probing depth did not exceed 3 mm. Conclusion. Combined treatment procedure involving nonsurgical root canal therapy and surgical periodontal regenerative treatment can be a predictable technique in treating combined endodontic-periodontal lesions caused by radicular groove.

Large eddy simulation of the subcritical flow over a V grooved circular cylinder

International Nuclear Information System (INIS)

Alonzo-García, A.; Gutiérrez-Torres, C. del C.; Jiménez-Bernal, J.A.

2015-01-01

Highlights: • We compared numerically the turbulent flow over a smooth circular cylinder and a V grooved cylinder in the subcritical regime. • Turbulence intensities in both streamwise and normal direction suffered attenuations. • The swirls structures on grooves peaks seemed to have a cyclic behavior. • The evolution of the flow inside grooves showed that swirls structures located in peaks suffered elongations in the normal direction. • The secondary vortex structures formed in the grooved cylinder near wake were smaller in comparison of the smooth cylinder flow. - Abstract: In this paper, a comparative numerical study of the subcritical flow over a smooth cylinder and a cylinder with V grooves (Re = 140,000) is presented. The implemented technique was the Large Eddy Simulation (LES), which according to Kolmogorov's theory, resolves directly the most energetic largest eddies and models the smallest and considered universal high frequency ones. The Navier-Stokes (N-S) equations were solved using the commercial software ANSYS FLUENT V.12.1, which applied the finite volume method (FVM) to discretize these equations in their unsteady and incompressible forms. The grid densities were 2.6 million cells and 13.5 million cells for the smooth and V grooved cylinder, respectively. Both meshes were composed of structured hexahedral cells and close to the wall of the cylinders, additional refinements were employed in order to obtain y +<5 values. All cases were simulated during at least 15 vortex shedding cycles with the aim of obtaining significant statistical data. Results: showed that for both cases (smooth and V grooved cylinder flow), the numerical code was capable of reproducing the most important physical quantities of the subcritical regime. Velocity distribution and turbulence intensity in the flow direction suffered a slight attenuation along the wake, as a consequence of grooves perturbation, which also caused an increase in the pressure coefficient

'Tongue-and-groove' effect in intensity modulated radiotherapy with static multileaf collimator fields

International Nuclear Information System (INIS)

Que, W; Kung, J; Dai, J

2004-01-01

The 'tongue-and-groove problem' in step-and-shoot delivery of intensity modulated radiotherapy is investigated. A 'tongue-and-groove' index (TGI) is introduced to quantify the 'tongue-and-groove' effect in step-and-shoot delivery. Four different types of leaf sequencing methods are compared. The sliding window method and the reducing level method use the same number of field segments to deliver the same intensity map, but the TGI is much less for the reducing level method. The leaf synchronization method of Van Santvoort and Heijmen fails in step-and-shoot delivery, but a new method inspired by the method of Van Santvoort and Heijmen is shown to eliminate 'tongue-and-groove' underdosage completely

Experiment Description and Results for Arrival Operations Using Interval Management with Spacing to Parallel Dependent Runways (IMSPiDR)

Science.gov (United States)

Baxley, Brian T.; Murdoch, Jennifer L.; Swieringa, Kurt A.; Barmore, Bryan E.; Capron, William R.; Hubbs, Clay E.; Shay, Richard F.; Abbott, Terence S.

2013-01-01

The predicted increase in the number of commercial aircraft operations creates a need for improved operational efficiency. Two areas believed to offer increases in aircraft efficiency are optimized profile descents and dependent parallel runway operations. Using Flight deck Interval Management (FIM) software and procedures during these operations, flight crews can achieve by the runway threshold an interval assigned by air traffic control (ATC) behind the preceding aircraft that maximizes runway throughput while minimizing additional fuel consumption and pilot workload. This document describes an experiment where 24 pilots flew arrivals into the Dallas Fort-Worth terminal environment using one of three simulators at NASA?s Langley Research Center. Results indicate that pilots delivered their aircraft to the runway threshold within +/- 3.5 seconds of their assigned time interval, and reported low workload levels. In general, pilots found the FIM concept, procedures, speeds, and interface acceptable. Analysis of the time error and FIM speed changes as a function of arrival stream position suggest the spacing algorithm generates stable behavior while in the presence of continuous (wind) or impulse (offset) error. Concerns reported included multiple speed changes within a short time period, and an airspeed increase followed shortly by an airspeed decrease.

Experimental Investigation of Concrete Runway Snow Melting Utilizing Heat Pipe Technology

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Fengchen Chen

2018-01-01

Full Text Available A full scale snow melting system with heat pipe technology is built in this work, which avoids the negative effects on concrete structure and environment caused by traditional deicing chemicals. The snow melting, ice-freezing performance and temperature distribution characteristics of heat pipe concrete runway were discussed by the outdoor experiments. The results show that the temperature of the concrete pavement is greatly improved with the heat pipe system. The environment temperature and embedded depth of heat pipe play a dominant role among the decision variables of the snow melting system. Heat pipe snow melting pavement melts the snow completely and avoids freezing at any time when the environment temperature is below freezing point, which is secure enough for planes take-off and landing. Besides, the exportation and recovery of geothermal energy indicate that this system can run for a long time. This paper will be useful for the design and application of the heat pipe used in the runway snow melting.

Experimental Investigation of Concrete Runway Snow Melting Utilizing Heat Pipe Technology.

Science.gov (United States)

Chen, Fengchen; Su, Xin; Ye, Qing; Fu, Jianfeng

2018-01-01

A full scale snow melting system with heat pipe technology is built in this work, which avoids the negative effects on concrete structure and environment caused by traditional deicing chemicals. The snow melting, ice-freezing performance and temperature distribution characteristics of heat pipe concrete runway were discussed by the outdoor experiments. The results show that the temperature of the concrete pavement is greatly improved with the heat pipe system. The environment temperature and embedded depth of heat pipe play a dominant role among the decision variables of the snow melting system. Heat pipe snow melting pavement melts the snow completely and avoids freezing at any time when the environment temperature is below freezing point, which is secure enough for planes take-off and landing. Besides, the exportation and recovery of geothermal energy indicate that this system can run for a long time. This paper will be useful for the design and application of the heat pipe used in the runway snow melting.

NMR studies of DNA oligomers and their interactions with minor groove binding ligands

Energy Technology Data Exchange (ETDEWEB)

Fagan, Patricia A. [Univ. of California, Berkeley, CA (United States). Dept. of Chemistry

1996-05-01

The cationic peptide ligands distamycin and netropsin bind noncovalently to the minor groove of DNA. The binding site, orientation, stoichiometry, and qualitative affinity of distamycin binding to several short DNA oligomers were investigated by NMR spectroscopy. The oligomers studied contain A,T-rich or I,C-rich binding sites, where I = 2-desaminodeoxyguanosine. I•C base pairs are functional analogs of A•T base pairs in the minor groove. The different behaviors exhibited by distamycin and netropsin binding to various DNA sequences suggested that these ligands are sensitive probes of DNA structure. For sites of five or more base pairs, distamycin can form 1:1 or 2:1 ligand:DNA complexes. Cooperativity in distamycin binding is low in sites such as AAAAA which has narrow minor grooves, and is higher in sites with wider minor grooves such as ATATAT. The distamycin binding and base pair opening lifetimes of I,C-containing DNA oligomers suggest that the I,C minor groove is structurally different from the A,T minor groove. Molecules which direct chemistry to a specific DNA sequence could be used as antiviral compounds, diagnostic probes, or molecular biology tools. The author studied two ligands in which reactive groups were tethered to a distamycin to increase the sequence specificity of the reactive agent.

Tunable THz notch filter with a single groove inside parallel-plate waveguides.

Science.gov (United States)

Lee, Eui Su; Jeon, Tae-In

2012-12-31

A single groove in a parallel-plate waveguide (PPWG) has been applied to a tunable terahertz (THz) notch filter with a transverse-electromagnetic (TEM) mode. When the air gap between the metal plates of the PPWG is controlled from 60 to 240 μm using a motor controlled translation stage or a piezo-actuator, the resonant frequency of the notch filter is changed from 1.75 up to 0.62 THz, respectively. Therefore, the measured tunable sensitivity of the notch filter increases to 6.28 GHz/μm. The measured resonant frequencies were found to be in good agreement with the calculation using an effective groove depth. Using a finite-difference time-domain (FDTD) simulation, we also demonstrate that the sensitivity of a THz microfluidic sensor can be increased via a small air gap, a narrow groove width, and a deep groove depth.

Study on the Correlation Between Dynamical Behavior and Friction/Wear Mechanism Under the Effect of Grooves

Science.gov (United States)

Zhu, Z. Y.; Mo, J. L.; Wang, D. W.; Zhao, J.; Zhu, M. H.; Zhou, Z. R.

2018-04-01

In this work, the interfacial friction and wear and vibration characteristics are studied by sliding a chromium bearing steel ball (AISI 52100) over both multi-grooved and single-grooved forged steel disks (20CrMnMo) at low and high rotating speeds in order to reveal the effect mechanism of groove-textured surface on tribological behaviors. The results show that the grooves modify the contact state of the ball and the disk at the contact interface. This consequently causes variations in the normal displacement, normal force, and friction force signals. The changes in these three signals become more pronounced with increasing groove width at a low speed. The collision behavior between the ball and the groove increase the amplitude of vibration acceleration at a high speed. The test results suggest that grooves with appropriate widths could trap wear debris on the ball surface while avoiding a strong collision between the disk and the ball, resulting in an improvement in the wear states.

Effect of longitudinal grooves of the scallop surface on aerodynamic performance

International Nuclear Information System (INIS)

Kim, Tae Hun; Choi, Hae Cheon

2008-01-01

Some of the scallops like Amesium balloti have an excellent level-swimming ability, i.e. they can swim about 20m by single level swimming with a maximum swimming velocity of about 1.6m/s in the sea. On the other hand, some species like Patinopecten yessoensis have longitudinal grooves on the upper and lower surfaces and others do not. Therefore, in the present study, we measure the lift and drag forces on a real scallop model (Patinopecten yessoensis) in a wind tunnel. Experiments are performed at the Reynolds number of 75,000 based on the maximum chord length, which is within the swimming condition of real scallop (Re=30,000∼300,000). To see the effect of longitudinal grooves, we measure the aerodynamic forces on a scallop model by removing the grooves. With the grooves, the lift force increases at low angles of attack (α<10 .deg.). The drag force increases slightly at all the attack angles considered. The lift-to-drag ratio is increased by about 10% at α<10 .deg.

Laboratory and On-Site Tests for Rapid Runway Repair

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Federico Leonelli

2017-11-01

Full Text Available The attention to rapid pavement repair has grown fast in recent decades: this topic is strategic for the airport management process for civil purposes and peacekeeping missions. This work presents the results of laboratory and on-site tests for rapid runway repair, in order to analyse and compare technical and mechanical performances of 12 different materials currently used in airport. The study focuses on site repairs, a technique adopted most frequently than repairs with modular elements. After describing mechanical and physical properties of the examined materials (2 bituminous emulsions, 5 cement mortars, 4 cold bituminous mixtures and 1 expanding resin, the study presents the results of carried out mechanical tests. The results demonstrate that the best performing material is a one-component fast setting and hardening cement mortar with graded aggregates. This material allows the runway reopening 6 h after the work. A cold bituminous mixture (bicomponent premixed cold asphalt with water as catalyst and the ordinary cement concrete allow the reopening to traffic after 18 h, but both ensure a lower service life (1000 coverages than the cement mortar (10,000 coverages. The obtained results include important information both laboratory level and field, and they could be used by airport management bodies and road agencies when scheduling and evaluating pavement repairs.

Optimal Tempo for Groove: Its Relation to Directions of Body Movement and Japanese nori

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Takahide Etani

2018-04-01

Full Text Available The tendency for groove-based music to induce body movements has been linked to multiple acoustical factors. However, it is unclear how or whether tempo affects groove, although tempo significantly affects other aspects of music perception. To address this issue, the present study investigated effects of tempo, specific rhythmic organizations of patterns, and syncopation on groove and the induction of the sensation of wanting to move. We focused on the directions of body movement in particular by taking into account nori, which is an indigenous Japanese musical term used not only synonymously with groove, but also as a spatial metaphor indicating vertical or horizontal movement directions. Thus, the present study explored how groove was felt and defined, as well as how musical factors induced the sensation of wanting to move in cross-cultural context. A listening experiment was conducted using drum breaks as stimuli. Stimuli consisted of various rhythm patterns at six tempi from 60 to 200 BPM. The main findings are that: (1 an optimal tempo for groove existed for drum breaks at around 100–120 BPM, (2 an optimal tempo existed for the sensation of wanting to move the body in specific directions (i.e., back-and-forth and side-to-side, (3 groove and nori shared a similar concept of wanting to move but differed on several points (i.e., association with sense of pulse and fast tempo. Overall, the present study suggests that there is an optimal tempo for body movement related to groove. This finding has implications for the use of music or rhythmic stimuli to induce smooth motion in rehabilitation, therapy, or dance.

Optimal Tempo for Groove: Its Relation to Directions of Body Movement and Japanese nori.

Science.gov (United States)

Etani, Takahide; Marui, Atsushi; Kawase, Satoshi; Keller, Peter E

2018-01-01

The tendency for groove-based music to induce body movements has been linked to multiple acoustical factors. However, it is unclear how or whether tempo affects groove, although tempo significantly affects other aspects of music perception. To address this issue, the present study investigated effects of tempo, specific rhythmic organizations of patterns, and syncopation on groove and the induction of the sensation of wanting to move. We focused on the directions of body movement in particular by taking into account nori , which is an indigenous Japanese musical term used not only synonymously with groove, but also as a spatial metaphor indicating vertical or horizontal movement directions. Thus, the present study explored how groove was felt and defined, as well as how musical factors induced the sensation of wanting to move in cross-cultural context. A listening experiment was conducted using drum breaks as stimuli. Stimuli consisted of various rhythm patterns at six tempi from 60 to 200 BPM. The main findings are that: (1) an optimal tempo for groove existed for drum breaks at around 100-120 BPM, (2) an optimal tempo existed for the sensation of wanting to move the body in specific directions (i.e., back-and-forth and side-to-side), (3) groove and nori shared a similar concept of wanting to move but differed on several points (i.e., association with sense of pulse and fast tempo). Overall, the present study suggests that there is an optimal tempo for body movement related to groove. This finding has implications for the use of music or rhythmic stimuli to induce smooth motion in rehabilitation, therapy, or dance.

Optimal leaf sequencing with elimination of tongue-and-groove underdosage

Energy Technology Data Exchange (ETDEWEB)

Kamath, Srijit [Department of Computer and Information Science and Engineering, University of Florida, Gainesville, FL (United States); Sahni, Sartaj [Department of Computer and Information Science and Engineering, University of Florida, Gainesville, FL (United States); Palta, Jatinder [Department of Radiation Oncology, University of Florida, Gainesville, FL (United States); Ranka, Sanjay [Department of Computer and Information Science and Engineering, University of Florida, Gainesville, FL (United States); Li, Jonathan [Department of Radiation Oncology, University of Florida, Gainesville, FL (United States)

2004-02-07

The individual leaves of a multileaf collimator (MLC) have a tongue-and-groove or stepped-edge design to minimize leakage radiation between adjacent leaves. This design element has a drawback in that it creates areas of underdosages in intensity-modulated photon beams unless a leaf trajectory is specifically designed such that for any two adjacent leaf pairs, the direct exposure under the tongue-and-groove is equal to the lower of the direct exposures of the leaf pairs. In this work, we present a systematic study of the optimization of a leaf sequencing algorithm for segmental multileaf collimator beam delivery that completely eliminates areas of underdosages due to tongue-and-groove or stepped-edge design of the MLC. Simultaneous elimination of tongue-and-groove effect and leaf interdigitation is also studied. This is an extension of our previous work (Kamath et al 2003a Phys. Med. Biol. 48 307) in which we described a leaf sequencing algorithm that is optimal for monitor unit (MU) efficiency under most common leaf movement constraints that include minimum leaf separation. Compared to our previously published algorithm (without constraints), the new algorithms increase the number of sub-fields by approximately 21% and 25%, respectively, but are optimal in MU efficiency for unidirectional schedules. (note)

Optimal leaf sequencing with elimination of tongue-and-groove underdosage

International Nuclear Information System (INIS)

Kamath, Srijit; Sahni, Sartaj; Palta, Jatinder; Ranka, Sanjay; Li, Jonathan

2004-01-01

The individual leaves of a multileaf collimator (MLC) have a tongue-and-groove or stepped-edge design to minimize leakage radiation between adjacent leaves. This design element has a drawback in that it creates areas of underdosages in intensity-modulated photon beams unless a leaf trajectory is specifically designed such that for any two adjacent leaf pairs, the direct exposure under the tongue-and-groove is equal to the lower of the direct exposures of the leaf pairs. In this work, we present a systematic study of the optimization of a leaf sequencing algorithm for segmental multileaf collimator beam delivery that completely eliminates areas of underdosages due to tongue-and-groove or stepped-edge design of the MLC. Simultaneous elimination of tongue-and-groove effect and leaf interdigitation is also studied. This is an extension of our previous work (Kamath et al 2003a Phys. Med. Biol. 48 307) in which we described a leaf sequencing algorithm that is optimal for monitor unit (MU) efficiency under most common leaf movement constraints that include minimum leaf separation. Compared to our previously published algorithm (without constraints), the new algorithms increase the number of sub-fields by approximately 21% and 25%, respectively, but are optimal in MU efficiency for unidirectional schedules. (note)

Investigation of enhanced condensation heat transfer outside vertical titanium circularly-grooved tube

International Nuclear Information System (INIS)

Zhaorigetu; Huang Weitang; Lv Xiangbo; Liu Feng

2005-01-01

The investigation of enhanced condensation heat transfer had been conducted on the outside vertical Titanium circularly-grooved tube. The experimental result indicates that the Titanium circularly-grooved tube is fairly efficient in enhancing the heat transfer. Within the experimental scope, the total heat transfer coefficient of the optimum circularly-grooved tube is 1.12 to 1.36 times of that of the Titanium smooth tube. Through regression analysis on the experimental data, the experimental correlations for the inside heat transfer coefficient, the condensation heat transfer coefficient on film condensation and the friction coefficient were achieved. (authors)

Mathematical modeling of photovoltaic thermal PV/T system with v-groove collector

Science.gov (United States)

Zohri, M.; Fudholi, A.; Ruslan, M. H.; Sopian, K.

2017-07-01

The use of v-groove in solar collector has a higher thermal efficiency in references. Dropping the working heat of photovoltaic panel was able to raise the electrical efficiency performance. Electrical and thermal efficiency were produced by photovoltaic thermal (PV/T) system concurrently. Mathematical modeling based on steady-state thermal analysis of PV/T system with v-groove was conducted. With matrix inversion method, the energy balance equations are explained by means of the investigative method. The comparison results show that in the PV/T system with the V-groove collector is higher temperature, thermal and electrical efficiency than other collectors.

Raphides with barbs and grooves in Xanthosoma sagittifolium (Araceae).

Science.gov (United States)

Sakai, W S; Hanson, M; Jones, R C

1972-10-20

Raphides in petioles of Xanthosoma sagittifolium are needlelike crystals about 50 micrometers long. The rectangular cross sections have maximum dimensions of approximately 850 by 250 nanometers. The raphides have two distinct end structures. One end is narrow, acute, and tapered to a point; the other is broad, acute, and abruptly pointed. Barbs, about 750 angstroms long with tips oriented away from the narrow end, occur along the length of the raphide on ridges on either side of two longitudinal grooves. These grooves, located opposite each other, give the raphide cross section an H-shape.

The effect of expert performance microtiming on listeners’ experience of groove in swing or funk music

Directory of Open Access Journals (Sweden)

Olivier Senn

2016-10-01

Full Text Available This study tested the influence of expert performance microtiming on listeners' groove experience. Two professional rhythm section (bass/drums performances in swing and funk style were recorded, and the performances' original microtemporal deviations from a regular metronomic grid were scaled to several magnitude levels. Music expert (n=79 and non-expert (n=81 listeners rated the groove qualities of stimuli using a newly developed questionnaire that measures three dimensions of the groove experience (Entrainment, Enjoyment, and the absence of Irritation. Findings show that music expert listeners were more sensitive to microtiming manipulations than non-experts. Across both expertise groups and for both styles, groove ratings were high for microtiming magnitudes equal or smaller than those originally performed and decreased for exaggerated microtiming magnitudes. In particular, both the fully quantized music and the music with the originally performed microtiming pattern were rated equally high on groove. This means that neither the claims of PD theory (that microtiming deviations are necessary for groove nor the opposing exactitude hypothesis (that microtiming deviations are detrimental to groove were supported by the data.

Sequence specificity and biological consequences of drugs that bind covalently in the minor groove of DNA

International Nuclear Information System (INIS)

Hurley, L.H.; Needham-VanDevanter, D.R.

1986-01-01

DNA ligands which bind within the minor groove of DNA exhibit varying degrees of sequence selectivity. Factors which contribute to nucleotide sequence recognition by minor groove ligands have been extensively investigated. Electrostatic interactions, ligand and DNA dehydration energies, hydrophobic interactions and steric factors all play significant roles in sequence selectivity in the minor groove. Interestingly, ligand recognition of nucleotide sequence in the minor groove does not involve significant hydrogen bonding. This is in sharp contrast to cellular enzyme and protein recognition of nucleotide sequence, which is achieved in the major groove via specific hydrogen bond formation between individual bases and the ligand. The ability to read nucleotide sequence via hydrogen bonding allows precise binding of proteins to specific DNA sequences. Minor groove ligands examined to date exhibit a much lower sequence specificity, generally binding to a subset of possible sequences, rather than a single sequence. 19 refs., 7 figs

Vertical Temperature Simulation of Pegasus Runway, McMurdo Station, Antarctica

Science.gov (United States)

2015-01-01

Polar Programs PSP Precision Spectral Pyranometer SPAWAR Space and Naval Warfare Systems Command ERDC/CRREL TR-15-2 ix Unit Conversion Factors...site was measured (M. Knuth*, pers. comm.) in 15-minute intervals from 29 October 2010 until 5 February 2011. Two broadband pyranometers (Eppley...Precision Spectral Pyranometer ) were mounted on a mast immediately adjacent to the runway. One measured downwelling radiation and the other upwelling

Uncertainty Analysis for the Evaluation of a Passive Runway Arresting System

Science.gov (United States)

Deloach, Richard; Marlowe, Jill M.; Yager, Thomas J.

2009-01-01

This paper considers the stopping distance of an aircraft involved in a runway overrun incident when the runway has been provided with an extension comprised of a material engineered to induce high levels of rolling friction and drag. A formula for stopping distance is derived that is shown to be the product of a known formula for the case of friction without drag, and a dimensionless constant between 0 and 1 that quantifies the further reduction in stopping distance when drag is introduced. This additional quantity, identified as the Drag Reduction Factor, D, is shown to depend on the ratio of drag force to friction force experienced by the aircraft as it enters the overrun area. The specific functional form of D is shown to depend on how drag varies with speed. A detailed uncertainty analysis is presented which reveals how the uncertainty in estimates of stopping distance are influenced by experimental error in the force measurements that are acquired in a typical evaluation experiment conducted to assess candidate overrun materials.

U-shaped micro-groove fiber based on femtosecond laser processing for humidity sensing

Science.gov (United States)

Fu, Gui; Ma, Li-li; Su, Fu-fang; Shi, Meng

2018-05-01

A novel optical fiber sensor with a U-shaped micro-groove structure ablated by femtosecond laser on single-mode fiber for measuring air relative humidity (RH) is reported in this paper. In order to improve the accuracy of sensor, a graphene oxide (GO)/polyvinyl alcohol (PVA) composite film is coated on the surface of micro-groove structure. In the U-shaped micro-groove structure, the remaining core and micro-cavity in the micro-groove make up two major optical propagation paths, forming a Mach-Zehnder interferometer (MZI). The sensor has a good linear response within the RH range of 30%—85%, and the maximum sensitivity can reach 0.638 1 nm/%RH. The effect of temperature on the overall performance of the humidity sensor is also investigated. As a new type of all-fiber device, the sensor shows excellent sensitivity and stability.

Trabectedin – the DNA minor groove binder

Directory of Open Access Journals (Sweden)

G. A. Belitsky

2015-01-01

Full Text Available Trabectedin (ET-743, Yondelis is an alkaloid that was originally isolated from the Caribbean Sea squirt, Ecteinascidia turbinata and is now produced synthetically. Its chemical structure consists in three fused tetrahydroisoquinoline rings. Two of them, A and B, binds covalently to guanine residues in the minor groove of the DNA double helix to bend the molecule toward the major groove and the third ring C protrudes from the DNA duplex, apparently allowing interactions with several nuclear proteins. Binding to the minor groove of DNA, trabectedin trigger a cascade of events that interfere with several transcription factors, DNA binding proteins, and DNA repair pathways in particular nucleotide excision repair. It acts both as a DNA-alkylating drug and topoisomerase poison. Trabectedin-DNA adduct traps the nucleotide excision repair proteins repairing the DNA damage in transcribing genes and induces DNA strand breaks. Cells deficient in homologous recombination pathway which repairs these double-strand breaks show increased sensitivity to trabectedin. The most sensitive of them were myxoid liposarcomas. Trabectedin is also effective in chemotherapy-experienced patients with advanced, recurrent liposarcoma or leiomyosarcoma as well as in women with ovarian cancer and breast cancer with BRCAness phenotype. Besides of tumor cells Trabectedin inhibits inflammatory cells by affecting directly monocytes and tumorassociated macrophages and indirectly by inhibiting production of inflammatory mediators, the cytokines and chemokines. It inhibits also the MDR-1 gene, which is responsible for the resistance of cancer cells to chemotherapeutic agents and strikes tumor angiogenesis.

Los Angeles International Airport Runway Incursion Studies: Phase III--Center-Taxiway Simulation

Science.gov (United States)

Madson, Michael D.

2004-01-01

Phase III of the Los Angeles International Airport Runway Incursion Studies was conducted, under an agreement with HNTB Corporation, at the NASA Ames FutureFlight Central (FFC) facility in June 2003. The objective of the study was the evaluation of a new center-taxiway concept at LAX. This study is an extension of the Phase I and Phase II studies previously conducted at FFC. This report presents results from Phase III of the study, in which a center-taxiway concept between runways 25L and 25R was simulated and evaluated. Phase III data were compared objectively against the Baseline data. Subjective evaluations by participating LAX controllers were obtained with regard to workload, efficiency, and safety criteria. To facilitate a valid comparison between Baseline and Phase III data, the same scenarios were used for Phase III that were tested during Phases I and II. This required briefing participating controllers on differences in airport and airline operations between 2001 and today.

A Robust Vision-based Runway Detection and Tracking Algorithm for Automatic UAV Landing

KAUST Repository

Abu Jbara, Khaled F.

2015-01-01

and attitude angle estimates to allow a more robust tracking of the runway under turbulence. We illustrate the performance of the proposed lane detection and tracking scheme on various experimental UAV flights conducted by the Saudi Aerospace Research Center

Atypical olfactory groove meningioma associated with uterine fibromatosis; case report

Directory of Open Access Journals (Sweden)

Toma I. Papacocea

2016-11-01

Full Text Available The concomitant presence of the olfactory groove meningioma with uterine fibrosis is very rare. Our report presents the case of a giant olfactory groove meningioma revealed after a uterine fibroma resection in a 44 years-old female, due to a generalized seizure 10 days after operation. Cranial CT-scan identified the tumor as an olfactory groove meningioma. The tumor was operated with a macroscopically complete resection; the endothermal coagulation of the dura attachment was performed (Simpson II with a good postoperative evolution. Laboratory results showed the presence of receptors for steroid hormones both in meningioma and uterine tumor, and the histopathological examination revealed an atypical meningioma with 17% proliferation markers. Our findings suggest that even though meningiomas are benign tumors and a complete resection usually indicates a good prognosis, the association with uterine fibromatosis and the presence of high percentage of steroid receptors creates a higher risk to relapse, imposing therefore a good monitoring.

Comparative evaluation of three heat transfer enhancement strategies in a grooved channel

Energy Technology Data Exchange (ETDEWEB)

Herman, C.; Kang, E. [Dept. of Mechanical Engineering, Johns Hopkins Univ., Baltimore, MD (United States)

2001-09-01

Results of a comparative evaluation of three heat transfer enhancement strategies for forced convection cooling of a parallel plate channel populated with heated blocks, representing electronic components mounted on printed circuit boards, are reported. Heat transfer in the reference geometry, the asymmetrically heated parallel plate channel, is compared with that for the basic grooved channel, and the same geometry enhanced by cylinders and vanes placed above the downstream edge of each heated block. In addition to conventional heat transfer and pressure drop measurements, holographic interferometry combined with high-speed cinematography was used to visualize the unsteady temperature fields in the self-sustained oscillatory flow. The locations of increased heat transfer within one channel periodicity depend on the enhancement technique applied, and were identified by analyzing the unsteady temperature distributions visualized by holographic interferometry. This approach allowed gaining insight into the mechanisms responsible for heat transfer enhancement. Experiments were conducted at moderate flow velocities in the laminar, transitional and turbulent flow regimes. Reynolds numbers were varied in the range Re = 200-6500, corresponding to flow velocities from 0.076 to 2.36 m/s. Flow oscillations were first observed between Re = 1050 and 1320 for the basic grooved channel, and around Re = 350 and 450 for the grooved channels equipped with cylinders and vanes, respectively. At Reynolds numbers above the onset of oscillations and in the transitional flow regime, heat transfer rates in the investigated grooved channels exceeded the performance of the reference geometry, the asymmetrically heated parallel plate channel. Heat transfer in the grooved channels enhanced with cylinders and vanes showed an increase by a factor of 1.2-1.8 and 1.5-3.5, respectively, when compared to data obtained for the basic grooved channel; however, the accompanying pressure drop penalties

Influence of edge conditions on material ejection from periodic grooves in laser shock-loaded tin

Energy Technology Data Exchange (ETDEWEB)

Rességuier, T. de; Roland, C. [Institut PPRIME, UPR 3346, CNRS, ENSMA, Université de Poitiers, 1 ave. Clément Ader, 86961 Futuroscope Cedex (France); Prudhomme, G.; Lescoute, E.; Mercier, P. [CEA, DAM, DIF, 91297 Arpajon (France); Loison, D. [Institut de Physique de Rennes, CNRS, Université de Rennes 1, 35042 Rennes (France)

2016-05-14

In a material subjected to high dynamic compression, the breakout of a shock wave at a rough free surface can lead to the ejection of high velocity debris. Anticipating the ballistic properties of such debris is a key safety issue in many applications involving shock loading, including pyrotechnics and inertial confinement fusion experiments. In this paper, we use laser driven shocks to investigate particle ejection from calibrated grooves of micrometric dimensions and approximately sinusoidal profile in tin samples, with various boundary conditions at the groove edges, including single groove and periodic patterns. Fast transverse shadowgraphy provides ejection velocities after shock breakout. They are found to depend not only on the groove depth and wavelength, as predicted theoretically and already observed in the past, but also, unexpectedly, on the edge conditions, with a jet tip velocity significantly lower in the case of a single groove than behind a periodic pattern.

Trial design and manufacture of double spiral grooved vacuum pump; Double neji mizoshiki shinku pump no shisaku

Energy Technology Data Exchange (ETDEWEB)

Iguchi, M.; Sawada, T.; Sugiyama, W. [Akita University, Akita (Japan). Faculty of Mining; Watanabe, M.

1997-04-25

A spiral grooved vacuum pump and a compound molecular pump (the combination of a spiral grooved pump and a turbomolecular pump) are widely used in the thin-film industry for processes such as semiconductor production. Pumping performance is high at pressures below 1 000 Pa and low at pressures above 1000 Pa when the clearance between rotor and stator is on the order of 0.1 mm, which is the practical value for industrial use. The double spiral grooved vacuum pump is thought to have better pumping performance at such high pressures than the conventional spiral grooved vacuum pump. The aim of this study is to investigate the feasibility of use of the double spiral grooved vacuum pump at pressures above 1000 Pa. A double spiral grooved vacuum pump with a rotor of 150 mm diameter and 190 mm length has been designed and manufactured. Its pumping performance has been tested by experiments. The test results show the improvement in the performance at pressures above 1000 Pa compared to the conventional spiral grooved vacuum pump. 2 refs., 12 figs., 2 tabs.

Spiral groove seal. [for hydraulic rotating shaft

Science.gov (United States)

Ludwig, L. P. (Inventor)

1973-01-01

Mating flat surfaces inhibit leakage of a fluid around a stationary shaft. A spiral groove pattern produces a pumping action toward the fluid when the shaft rotates which prevents leakage while a generated hydraulic lifting force separates the mating surfaces to minimize wear.

Ancient schwannoma at the olfactory groove mimicking meningioma: A case report

Energy Technology Data Exchange (ETDEWEB)

Heo, Young Jin; Jeong, Hae Woong [Dept. of Radiology, Busan Paik Hospital, Inje University College of Medicine, Busan (Korea, Republic of)

2015-12-15

Schwannomas are benign slow-growing nerve sheath tumors, which can develop in any peripheral or central nerve that contains Schwann cells. Schwannomas located near the olfactory groove are extremely rare and radiological diagnosis can be difficult. Moreover, ancient schwannoma is an uncommon variant, and radiologic findings are rarely reported. Herein, we reported a surgically confirmed case of ancient schwannoma at the olfactory groove in a 44-year-old woman presenting with headache and visual disturbance. Brain magnetic resonance imaging (MRI) showed a solid and cystic extra-axial mass located in the subfrontal area mimicking an olfactory groove meningioma. Histopathologic diagnosis of ancient schwannoma was confirmed by immunohistochemical staining for S100, CD56, vimentin, and other markers. Furthermore, we described the clinical manifestations, MRI characteristics, and histopathologic findings of the case, and presented a review of related literature.

Polarizing beam splitter of deep-etched triangular-groove fused-silica gratings.

Science.gov (United States)

Zheng, Jiangjun; Zhou, Changhe; Feng, Jijun; Wang, Bo

2008-07-15

We investigated the use of a deep-etched fused-silica grating with triangular-shaped grooves as a highly efficient polarizing beam splitter (PBS). A triangular-groove PBS grating is designed at a wavelength of 1550 nm to be used in optical communication. When it is illuminated in Littrow mounting, the transmitted TE- and TM-polarized waves are mainly diffracted in the minus-first and zeroth orders, respectively. The design condition is based on the average differences of the grating mode indices, which is verified by using rigorous coupled-wave analysis. The designed PBS grating is highly efficient over the C+L band range for both TE and TM polarizations (>97.68%). It is shown that such a triangular-groove PBS grating can exhibit a higher diffraction efficiency, a larger extinction ratio, and less reflection loss than the binary-phase fused-silica PBS grating.

Surgical Management of Olfactory Groove Meningiomas | El-Naggar ...

African Journals Online (AJOL)

Objective: To study the bifrontal approach to olfactory groove meningiomas ... in all patients was Grade I meningiomas (World Health Organization grading). ... Bifrontal approach offers excellent exposure, and when combined with modern ...

What musicians do to induce the sensation of groove in simple and complex melodies, and how listeners perceive it

Directory of Open Access Journals (Sweden)

Guy eMadison

2014-08-01

Full Text Available Groove is the experience of wanting to move when hearing music, such as snapping fingers or tapping feet. This is a central aspect of much music, in particular of music intended for dancing. While previous research has found considerable consistency in ratings of groove across individuals, it remains unclear how groove is induced, that is, what are the physical properties of the acoustic signal that differ between more and less groove-inducing versions. Here, we examined this issue with a performance experiment, in which 4 musicians performed 6 simple and 6 complex melodies in two conditions with the intention of minimizing and maximizing groove. Analyses of rhythmical and temporal properties from the performances demonstrated some general effects. For example, more groove was associated with more notes on faster metrical levels and syncopation, and less groove was associated with deadpan timing and destruction of the regular pulse. We did not observe that deviations from the metrical grid (i.e. micro-timing were a predictor of groove. A listener experiment confirmed that the musicians’ manipulations had the intended effects on the experience of groove. A Brunswikian lens model was applied, which estimates the performer-perceiver communication across the two experiments. It showed that the communication achievement for simple melodies was 0.62, and that the matching of performers’ and listeners’ use of 9 rhythmical cues was 0.83. For complex melodies with an already high level of groove, the corresponding values were 0.39 and 0.34, showing that it was much more difficult to take out groove from musical structures designed to induce groove.

Grooved floor system for cattle housing: ammonia emission reduction and good slip resistance

NARCIS (Netherlands)

Swierstra, D.; Braam, C.R.; Smits, M.C.J.

2001-01-01

To improve the slip resistance of solid floors in dairy cow houses and to achieve the ammonia emission reduction prescribed by the Dutch government, precast concrete floors with grooves and a dung scraper were investigated. The grooves parallel to the alley had 160 mm center-to-center spacing and

Structure of a Pheromone Receptor-Associated Mhc Molecule With An Open And Empty Groove

Energy Technology Data Exchange (ETDEWEB)

Olson, R.; Huey-Tubman, K.E.; Dulac, C.; Bjorkman, P.J.; /Caltech /Harvard U.

2006-10-06

Neurons in the murine vomeronasal organ (VNO) express a family of class Ib major histocompatibility complex (MHC) proteins (M10s) that interact with the V2R class of VNO receptors. This interaction may play a direct role in the detection of pheromonal cues that initiate reproductive and territorial behaviors. The crystal structure of M10.5, an M10 family member, is similar to that of classical MHC molecules. However, the M10.5 counterpart of the MHC peptide-binding groove is open and unoccupied, revealing the first structure of an empty class I MHC molecule. Similar to empty MHC molecules, but unlike peptide-filled MHC proteins and non-peptide-binding MHC homologs, M10.5 is thermally unstable, suggesting that its groove is normally occupied. However, M10.5 does not bind endogenous peptides when expressed in mammalian cells or when offered a mixture of class I-binding peptides. The F pocket side of the M10.5 groove is open, suggesting that ligands larger than 8-10-mer class I-binding peptides could fit by extending out of the groove. Moreover, variable residues point up from the groove helices, rather than toward the groove as in classical MHC structures. These data suggest that M10s are unlikely to provide specific recognition of class I MHC-binding peptides, but are consistent with binding to other ligands, including proteins such as the V2Rs.

Structure of a pheromone receptor-associated MHC molecule with an open and empty groove.

Directory of Open Access Journals (Sweden)

2005-08-01

Full Text Available Neurons in the murine vomeronasal organ (VNO express a family of class Ib major histocompatibility complex (MHC proteins (M10s that interact with the V2R class of VNO receptors. This interaction may play a direct role in the detection of pheromonal cues that initiate reproductive and territorial behaviors. The crystal structure of M10.5, an M10 family member, is similar to that of classical MHC molecules. However, the M10.5 counterpart of the MHC peptide-binding groove is open and unoccupied, revealing the first structure of an empty class I MHC molecule. Similar to empty MHC molecules, but unlike peptide-filled MHC proteins and non-peptide-binding MHC homologs, M10.5 is thermally unstable, suggesting that its groove is normally occupied. However, M10.5 does not bind endogenous peptides when expressed in mammalian cells or when offered a mixture of class I-binding peptides. The F pocket side of the M10.5 groove is open, suggesting that ligands larger than 8-10-mer class I-binding peptides could fit by extending out of the groove. Moreover, variable residues point up from the groove helices, rather than toward the groove as in classical MHC structures. These data suggest that M10s are unlikely to provide specific recognition of class I MHC-binding peptides, but are consistent with binding to other ligands, including proteins such as the V2Rs.

Optimization of Grooved Micromixer for Microengineering Technologies

DEFF Research Database (Denmark)

Sabotin, I.; Tristo, G.; Bissacco, Giuliano

2013-01-01

Due to the absence of turbulent flow and the slow diffusion process, mixing of solutions at micro-scale is a difficult task. This paper describes the optimization route towards the efficient design of a bottom grooved micromixer. Based on thoroughly discussed mixing mechanisms, the optimization w...

Solving the N-Queens Problem with GROOVE - Towards a Compendium of Best Practices

NARCIS (Netherlands)

Zambon, Eduardo; Rensink, Arend; Hermann, F.; Sauer, S.

We present a detailed solution to the N-queens puzzle using GROOVE, a graph transformation tool especially designed for state space exploration and analysis. While GROOVE has been freely available for more than a decade and has attracted a reasonable number of users, it is safe to say that only a

Thermal performance comparison of oscillating heat pipes with and without helical micro-grooves

Science.gov (United States)

Qu, Jian; Li, Xiaojun; Xu, Qian; Wang, Qian

2017-11-01

This paper presents an experimental investigation to compare the thermal performance of three closed loop oscillating heat pipes (OHPs) with and without internal helical microgrooves at vertical and horizontal orientations. All of these OHPs were made from copper tubes and have three turns with lengths of 70, 230 and 110 mm at the evaporator, adiabatic and condenser sections, respectively. Deionized water was used as the working fluid at a volumetric filling ratio of 50%. The internal diameters (IDs) of two smooth-tube OHPs are 4.0 and 4.8 mm, respectively, and the internal diameter of micro-grooved OHP without groove structures is about 4.5 mm. Experimental results demonstrated that the addition of groove structures make the OHP remarkably outperform smooth-tube OHPs in both effective thermal conductivity and thermal resistance. The thermal resistance of vertically-oriented micro-grooved OHP could be lowered to 0.057 °C/W associated with an effective thermal conductivity of 6.1 × 104 W/ (m·K) at the input heat flux of 3.8 × 104 W/m2. Compared to smooth-tube OHPs, preliminary mechanism analysis reveals that local heat transfer coefficients both at the heating and cooling sections of micro-grooved OHP could be significantly improved. Moreover, enhanced liquid backflow to the evaporator due to microgroove-induced capillarity is also responsible for the OHP performance enhancement.

Real-time terminal area trajectory planning for runway independent aircraft

Science.gov (United States)

Xue, Min

The increasing demand for commercial air transportation results in delays due to traffic queues that form bottlenecks along final approach and departure corridors. In urban areas, it is often infeasible to build new runways, and regardless of automation upgrades traffic must remain separated to avoid the wakes of previous aircraft. Vertical or short takeoff and landing aircraft as Runway Independent Aircraft (RIA) can increase passenger throughput at major urban airports via the use of vertiports or stub runways. The concept of simultaneous non-interfering (SNI) operations has been proposed to reduce traffic delays by creating approach and departure corridors that do not intersect existing fixed-wing routes. However, SNI trajectories open new routes that may overfly noise-sensitive areas, and RIA may generate more noise than traditional jet aircraft, particularly on approach. In this dissertation, we develop efficient SNI noise abatement procedures applicable to RIA. First, we introduce a methodology based on modified approximated cell-decomposition and Dijkstra's search algorithm to optimize longitudinal plane (2-D) RIA trajectories over a cost function that minimizes noise, time, and fuel use. Then, we extend the trajectory optimization model to 3-D with a k-ary tree as the discrete search space. We incorporate geography information system (GIS) data, specifically population, into our objective function, and focus on a practical case study: the design of SNI RIA approach procedures to Baltimore-Washington International airport. Because solutions were represented as trim state sequences, we incorporated smooth transition between segments to enable more realistic cost estimates. Due to the significant computational complexity, we investigated alternative more efficient optimization techniques applicable to our nonlinear, non-convex, heavily constrained, and discontinuous objective function. Comparing genetic algorithm (GA) and adaptive simulated annealing (ASA

Room to Groove?

DEFF Research Database (Denmark)

Seabrooke, Leonard

. As long as they stay within the parameters of legitimate financial practice to signal institutional isomorphism, the `groove', creditors may well allow borrowers room for change in self-determined ways. This paper maps out the historical and conceptual terrain concerning civilizing ideas about...... the legitimacy of financial practices within global capital markets, and investigates relationships between Western `civilizers' and Emerging Market Economies during the last two periods of financial globalization, the late-nineteenth/ early-twentieth centuries and the late-twentieth century.......The use of a `standard of civilization', a preferred form of socio-political organization, in global capital markets presents both constraints and opportunities for creditors and borrowers. When imposed, civilizing standards may change how a borrower would prefer to conduct their affairs. Creditors...

Behavior of aircraft antiskid braking systems on dry and wet runway surfaces - A velocity-rate-controlled, pressure-bias-modulated system

Science.gov (United States)

Stubbs, S. M.; Tanner, J. A.

1976-01-01

During maximum braking the average ratio of drag-force friction coefficient developed by the antiskid system to maximum drag-force friction coefficient available at the tire/runway interface was higher on dry surfaces than on wet surfaces. The gross stopping power generated by the brake system on the dry surface was more than twice that obtained on the wet surfaces. With maximum braking applied, the average ratio of side-force friction coefficient developed by the tire under antiskid control to maximum side-force friction available at the tire/runway interface of a free-rolling yawed tire was shown to decrease with increasing yaw angle. Braking reduced the side-force friction coefficient on a dry surface by 75 percent as the wheel slip ratio was increased to 0.3; on a flooded surface the coefficient dropped to near zero for the same slip ratio. Locked wheel skids were observed when the tire encountered a runway surface transition from dry to flooded, due in part to the response time required for the system to sense abrupt changes in the runway friction; however, the antiskid system quickly responded by reducing brake pressure and cycling normally during the remainder of the run on the flooded surface.

Measurement of sheath thickness by lining out grooves in the Hall-type stationary plasma thrusters

International Nuclear Information System (INIS)

Yu Daren; Wu Zhiwen; Ning Zhongxi; Wang Xiaogang

2007-01-01

Using grooves created along the axial direction of the discharge channel, a method for measuring sheath thickness in Hall-type stationary plasma thrusters has been developed. By distorting the wall surface using these grooves, it is possible to numerically study the effect of the wall surface on the sheath and near wall conductivity. Monte Carlo method is applied to calculate the electron temperature variation with different groove depths. The electron dynamic process in the plasma is described by a test particle method with the electron randomly entering the sheath from the discharge channel and being reflected back. Numerical results show that the reflected electron temperature is hardly affected by the wall surface if the groove depth is much less than the sheath thickness. On the other hand, the reflected electron temperature increases if the groove depth is much greater than the sheath thickness. The reflected electron temperature has a sharp jump when the depth of groove is on the order of the sheath thickness. The simulation is repeated with different sheath thicknesses and the results are the same. Therefore, a diagnosis mean of the sheath thickness can be developed based on the method. Also the simulation results are in accord with the experimental data. Besides, the measurement method may be applicable to other plasma device with similar orthogonal steady state electrical and magnetic fields

A test for the minimum scale of grooving on the Amatrice and Norcia earthquakes

Science.gov (United States)

Okamoto, K.; Brodsky, E. E.; Billi, A.

2017-12-01

As stress builds up along a fault, elastic strain energy builds until it cannot be accommodated by small-scale ductile deformation and then the fault brittlely fails. This brittle failure is associated with the grooving process that causes slickensides along fault planes. Therefore the scale at which slickensides disappear could be geological evidence of earthquake nucleation. Past studies found the minimum scale of grooving, however the studied fault surfaces were not exposed by recent earthquakes. These measurements could have been a product of chemical or mechanical weathering. On August 24th and October 30th of 2016, MW 6.0 and 6.5 earthquakes shook central Italy. The earthquakes caused decimeter to meter scale fault scarps along the Mt. Vettoretto Fault. Here, we analyze samples of a scarp using white light interferometry in order to determine if the minimum scale of grooving is present. Results suggest that grooving begins around 100 μm for these samples, which is consistent with previous findings of faults without any direct evidence of earthquakes. The measurement is also consistent with typical values of the frictional weakening distance Dc, which also is associated with a transition between ductile and brittle behavior. The measurements show that the minimum scale of grooving is a useful measure of the behavior of faults.

[Microsurgical removal of olfactory groove meningiomas].

Science.gov (United States)

Liang, Ri-Sheng; Zhou, Liang-Fu; Mao, Ying; Zhang, Rong; Yang, Wei-Zhong

2011-01-01

To explore an effective method for further improving the surgical results of treatment of olfactory groove meningiomas. Sixty seven cases of olfactory groove meningiomas were treated by microneurosurgery, among which fifty seven were de novo cases, eight were recurrent tumors and the other two re-recurrent cases. Modified Derome approach was used in 12 cases, bilateral subfrontal approach in 28 cases, modified pterional approach in 21 cases and unilateral subfrontal approach in six cases. Tumors were resected microsurgically with radical removal of invaded dura, bone, and paranasal sinus mucosa. Reconstruction was performed in patients with skull base defect. Simpson grade I removal was accomplished in 59 cases, grade II in seven cases and grade IV in one case. Among 57 patients with de novo tumor, Simpson I resection was accomplished in 54 cases. Postoperative rhinorrhea and intracranial infection occurred in one case and was cured after temporal lumbar CSF drainage and antibiotic therapy. Two patients (2.9%) died within one month after operation, i.e.one aged patient of heart failure and the other of severe hypothalamus complication. Forty seven patients (72.3%) were followed up from one to ten years with an average of five years and four months. With the exception of two cases died, among the alive 45 patients, there were only three patients with tumor recurrence, which had undergone Simpson II or IV tumor resection. No recurrence was found in cases with Simpson I tumor removal. Previous blurred vision was not improved in three patients, hemiparalysis in two patients, and the other patients recovered well, resuming previous jobs or being able to take care themselves. Total tumor removal (Simpson I) should be the surgical goal for treatment of olfactory groove meningiomas, especially for de novo cases. An appropriate approach is fundamental in the effort to remove an OGM totally. Appropriate anterior skull base reconstruction with vascularized material is

Cycle time improvement for plastic injection moulding process by sub groove modification in conformal cooling channel

Science.gov (United States)

Kamarudin, K.; Wahab, M. S.; Batcha, M. F. M.; Shayfull, Z.; Raus, A. A.; Ahmed, Aqeel

2017-09-01

Mould designers have been struggling for the improvement of the cooling system performance, despite the fact that the cooling system complexity is physically limited by the fabrication capability of the conventional tooling methods. However, the growth of Solid Free Form Technology (SFF) allow the mould designer to develop more than just a regular conformal cooling channel. Numerous researchers demonstrate that conformal cooling channel was tremendously given significant result in the improvement of productivity and quality in the plastic injection moulding process. This paper presents the research work that applies the passive enhancement method in square shape cooling channel to enhance the efficiency of cooling performance by adding the sub groove to the cooling channel itself. Previous design that uses square shape cooling channel was improved by adding various numbers of sub groove to meet the best sub groove design that able reduced the cooling time. The effect of sub groove design on cooling time was investigated by Autodesk Modlflow Insight software. The simulation results showed that the various sub groove designs give different values to ejection time. The Design 7 showed the lowest value of ejection time with 24.3% increment. The addition of sub groove significantly increased a coolant velocity and a rate of heat transfer from molten plastic to coolant.

Characterization of thermoset and thermoplastic polyurethane pads, and molded and non-optimized machined grooving methods for oxide chemical mechanical planarization applications

International Nuclear Information System (INIS)

Sampurno, Yasa; Borucki, Leonard; Zhuang, Yun; Misra, Sudhanshu; Holland, Karey; Boning, Duane; Philipossian, Ara

2009-01-01

This paper systematically studies the effect of pad material, grooving method and grooving pattern on interlayer dielectric chemical mechanical planarization. The tested polishing pads consist of thermoplastic and thermoset polyurethanes synthesized using two different processes. Grooves created using a molding technique are compared with grooves formed by mechanical cutting. The concentric groove design is also compared with the logarithmic positive spiral positive grooving design. Experimental data collected include removal rate, coefficient of friction, shear force variance, pad temperature and dynamic mechanical analyzer measurements. Scanning electron microscope images are used to correlate grooving methods with coefficient of friction and shear force variance measurements. Results show that all of the pads polish wafers in boundary lubrication mode with unique friction coefficient, shear force variance and pad temperature characteristics. Simulations using a two-step removal rate mechanism are performed to estimate the chemical and mechanical rate constants. The analysis indicates that the thermoplastic pad is more mechanically controlled than the thermoset pad and that molded grooving induces a more mechanically controlled process than non-optimized machined grooving

The impact of postoperative supraclavicular radiotherapy on tracheoesophageal groove lymph node metastasis in esophageal carcinoma

International Nuclear Information System (INIS)

Qian Pudong; Lu Jinchen; Mei Zeru; Zhu Jun

2005-01-01

Objective: To evaluate the prognostic factors of tracheoesophageal groove lymph node (TEGLN) metastasis in postoperative esophageal carcinoma. Methods: From January 1996 to December 1997, 101 postoperative cervical and thoracic esophageal carcinoma patients proved absence from tracheoesophageal groove lymph node (TEGIAN) metastasis before and after operation by physical examination and computer tomography examination were entered into this study. The patients were divided into three groups according to the treatment of supraclavicular region: no prophylactic radiotherapy (group A-, 30 patients); prophylactic radiotherapy with local dose < 45 Gy (Group B-, 71 patients); and prophylactic radiotherapy with local dose ≥45 Gy (Group C-, 19 patients). Radiotherapy was delivered by cobalt- 60 or 6 MV X-ray with the prescribed dose normalized to the point of tracheoesophageal groove, i. e, 5 cm in depth. The tracheoesophageal groove lymph node metastasis after treatment was observed. Results: The incidence of tracheoesophageal groove lymph node metastasis was 20% (6/30), 9.6% (5/71) and 0% (0/19) in groups A, B and C. Univariate analysis showed that there was significant difference of TEGLN metastasis between groups A and C only (P=0.039), but higher dose to supraclavicular region tended to lower the incidence of TEGLN metastasis. Multivariate analysis showed that only prophylactic radiotherapy to the supraclavicular region was independent prognostic factor for TEGLN metastasis (P=0.037). Gender, primary tumor site and pathological stage had no significant impact on TEGLN metastasis. Conclusions: Postoperative prophylactic supraclavicular region irradiation can lower the incidence of tracheoesophageal groove lymph node metastasis in esophageal carcinoma. Radiotherapy dose should not be less than 45 Gy and should be routinely normalized to a point 5 cm deep in the tracheoesophageal groove. (authors)

Research on fatigue behavior and residual stress of large-scale cruciform welding joint with groove

International Nuclear Information System (INIS)

Zhao, Xiaohui; Liu, Yu; Liu, Yong; Gao, Yuan

2014-01-01

Highlights: • The fatigue behavior of the large-scale cruciform welding joint with groove was studied. • The longitudinal residual stress of the large-scale cruciform welding joint was tested by contour method. • The fatigue fracture mechanism of the large-scale cruciform welding joint with groove was analyzed. - Abstract: Fatigue fracture behavior of the 30 mm thick Q460C-Z steel cruciform welded joint with groove was investigated. The fatigue test results indicated that fatigue strength of 30 mm thick Q460C-Z steel cruciform welded joint with groove can reach fatigue level of 80 MPa (FAT80). Fatigue crack source of the failure specimen initiated from weld toe. Meanwhile, the microcrack was also found in the fusion zones of the fatigue failure specimen, which was caused by weld quality and weld metal integrity resulting from the multi-pass welds. Two-dimensional map of the longitudinal residual stress of 30 mm thick Q460C-Z steel cruciform welded joint with groove was obtained by using the contour method. The stress nephogram of Two-dimensional map indicated that longitudinal residual stress in the welding center is the largest

Binding to the DNA Minor Groove by Heterocyclic Dications: From AT Specific Monomers to GC Recognition with Dimers

Science.gov (United States)

Nanjunda, Rupesh; Wilson, W. David

2012-01-01

Compounds that bind in the DNA minor groove have provided critical information on DNA molecular recognition, they have found extensive uses in biotechnology and they are providing clinically useful drugs against diseases as diverse as cancer and sleeping sickness. This review focuses on the development of clinically useful heterocyclic diamidine minor groove binders. These compounds have shown us that the classical model for minor groove binding in AT DNA sequences must be expanded in several ways: compounds with nonstandard shapes can bind strongly to the groove, water can be directly incorporated into the minor groove complex in an interfacial interaction, and the compounds can form cooperative stacked dimers to recognize GC and mixed AT/GC base pair sequences. PMID:23255206

Phantom's construction for dose measurement in brachytherapy

International Nuclear Information System (INIS)

Tri Harjanto; Hidayat Joko Puspito; Joko Triyanto

2009-01-01

In nuclear medicine, dose rate validation is the key for a successful process in therapy and diagnose of any deases. Therefore, the brachytherapy equipment being designed and constructed is to be validated its dose rate received by the radiated object. A phantom for such validation purpose is designed and constructed as a correct as if on site geometrical position of sources. The design of phantom consists of seven layers of flexi glass plates: 10 mm thick, 105 mm wide, and 280 mm length. All the plates are to be holed according to the size of the applicator to be used. Every surface of the flexi glass layers is grooved 1 mm wide, 1 mm depth, and 10 mm distance between the groove. The applicator inside the phantom is positioned at a certain reference for measurement. Every TLD installed has a fix position toward the reference coordinate and has an index number. By this system of phantom, the isodose system can be plotted. (author)

DNA minor groove electrostatic potential: influence of sequence-specific transitions of the torsion angle gamma and deoxyribose conformations.

Science.gov (United States)

Zhitnikova, M Y; Shestopalova, A V

2017-11-01

The structural adjustments of the sugar-phosphate DNA backbone (switching of the γ angle (O5'-C5'-C4'-C3') from canonical to alternative conformations and/or C2'-endo → C3'-endo transition of deoxyribose) lead to the sequence-specific changes in accessible surface area of both polar and non-polar atoms of the grooves and the polar/hydrophobic profile of the latter ones. The distribution of the minor groove electrostatic potential is likely to be changing as a result of such conformational rearrangements in sugar-phosphate DNA backbone. Our analysis of the crystal structures of the short free DNA fragments and calculation of their electrostatic potentials allowed us to determine: (1) the number of classical and alternative γ angle conformations in the free B-DNA; (2) changes in the minor groove electrostatic potential, depending on the conformation of the sugar-phosphate DNA backbone; (3) the effect of the DNA sequence on the minor groove electrostatic potential. We have demonstrated that the structural adjustments of the DNA double helix (the conformations of the sugar-phosphate backbone and the minor groove dimensions) induce changes in the distribution of the minor groove electrostatic potential and are sequence-specific. Therefore, these features of the minor groove sizes and distribution of minor groove electrostatic potential can be used as a signal for recognition of the target DNA sequence by protein in the implementation of the indirect readout mechanism.

Unified design of sinusoidal-groove fused-silica grating.

Science.gov (United States)

Feng, Jijun; Zhou, Changhe; Cao, Hongchao; Lu, Peng

2010-10-20

A general design rule of deep-etched subwavelength sinusoidal-groove fused-silica grating as a highly efficient polarization-independent or polarization-selective device is studied based on the simplified modal method, which shows that the device structure depends little on the incident wavelength, but mainly on the ratio of groove depth to incident wavelength and the ratio of wavelength to grating period. These two ratios could be used as the design guidelines for wavelength-independent structure from deep ultraviolet to far infrared. The optimized grating profile with a different function as a polarizing beam splitter, a polarization-independent two-port beam splitter, or a polarization-independent grating with high efficiency of -1st order is obtained at a wavelength of 1064 nm, and verified by using the rigorous coupled-wave analysis. The performance of the sinusoidal grating is better than a conventional rectangular one, which could be useful for practical applications.

Dance, Music, Meter and Groove: A Forgotten Partnership

Directory of Open Access Journals (Sweden)

W Tecumseh eFitch

2016-03-01

Full Text Available I argue that core aspects of musical rhythm, especially groove and syncopation, can only be fully understood in the context of their origins in the participatory social experience of dance. Musical meter is first considered in the context of bodily movement. I then offer an interpretation of the pervasive but somewhat puzzling phenomenon of syncopation in terms of acoustic emphasis on certain offbeat components of the accompanying dance style. The reasons for the historical tendency of many musical styles to divorce themselves from their dance-based roots are also briefly considered. To the extent that musical rhythms only make sense in the context of bodily movement, researchers interested in ecologically valid approaches to music cognition should make a more concerted effort to extend their analyses to dance, particularly if we hope to understand the cognitive constraints underlying rhythmic aspects of music like meter and groove.

Dance, Music, Meter and Groove: A Forgotten Partnership.

Science.gov (United States)

Fitch, W Tecumseh

2016-01-01

I argue that core aspects of musical rhythm, especially "groove" and syncopation, can only be fully understood in the context of their origins in the participatory social experience of dance. Musical meter is first considered in the context of bodily movement. I then offer an interpretation of the pervasive but somewhat puzzling phenomenon of syncopation in terms of acoustic emphasis on certain offbeat components of the accompanying dance style. The reasons for the historical tendency of many musical styles to divorce themselves from their dance-based roots are also briefly considered. To the extent that musical rhythms only make sense in the context of bodily movement, researchers interested in ecologically valid approaches to music cognition should make a more concerted effort to extend their analyses to dance, particularly if we hope to understand the cognitive constraints underlying rhythmic aspects of music like meter and groove.

Transverse grooved artefacts from southwestern Asia and northern Eurasia: Common traits and the reconstruction of function

Directory of Open Access Journals (Sweden)

Irina Usacheva

2016-10-01

Full Text Available Transverse grooved artefacts (TGA appeared as a new cultural element in Mesolithic-Proto-Neolithic sites in southwestern Asia. We know of similar artefacts from northern Africa. Hundreds of TGA have also been found in northern Eurasia. Some common traits were found in specimens from far apart territories, such as the non-abrasive heat-resistant nature of the raw materials, specificity of fragmentation without any signs of physical impact, the standard size of the grooves, association with a specific type of landscape, the similar economic level of the societies with which the items are associated, and use-wear marks in the grooves. Based on these regularities we can speak of a single main function for these artefacts which support the earlier reconstruction of R.L. and R.S. Solecki, suggesting that grooved stones were used for straightening cane and reed shafts under heating. Other evidence and traces that have been identified on the surface of TGA outside the groove could be associated with a variety of additional functions.

Tailoring channeled plasmon polaritons in metallic V-grooves

DEFF Research Database (Denmark)

Smith, Cameron; Thilsted, Anil Haraksingh; Marie, Rodolphe

2013-01-01

of propagating plasmons to optimize the trade-off between lateral confinement and loss [2]. Accordingly, the traits of CPPs in metallic V-grooves suggest their widespread implementation, with applications ranging from ultracompact photonic circuitry [3] to lab-on-a-chip sensing. Current CPP research focuses...

Regenerated collagen fibers with grooved surface texture: Physicochemical characterization and cytocompatibility

International Nuclear Information System (INIS)

Wang, Xiang; Wu, Tong; Wang, Wei; Huang, Chen; Jin, Xiangyu

2016-01-01

A novel type of protein fibers, regenerated collagen fibers (RC) from cattle skin, was prepared through wet-spinning. Due to the combined effect of solvent exchange and subsequent drawing process, the fibers were found to have a grooved surface texture. The grooves provided not only ordered topographical cues, but also increased surface area. Protein content of the RC fibers was confirmed by Fourier Transform infrared spectroscopy (FTIR) and ninhydrin color reaction. The fibers could be readily fabricated into nonwovens or other textiles, owning to their comparable physical properties to other commercialized fibers. Cell growth behavior on RC nonwovens suggested both early adhesion and prompt proliferation. The high moisture regain, good processability, along with the excellent cytocompatibility indicated that the RC fibers and nonwovens developed in this study might offer a good candidate for biomedical and healthcare applications. - Highlights: • Wet-spun regenerated collagen fibers having aligned surface grooves • Comparable physiochemical properties to commercialized fibers • Readily processed into nonwovens • Excellent cytocompatibility with prompt cell adhesion and proliferation

Regenerated collagen fibers with grooved surface texture: Physicochemical characterization and cytocompatibility

Energy Technology Data Exchange (ETDEWEB)

Wang, Xiang [Engineering Research Center of Technical Textiles, Ministry of Education, College of Textiles, Donghua University, Shanghai 201620 (China); Wu, Tong [College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620 (China); Wang, Wei [Engineering Research Center of Technical Textiles, Ministry of Education, College of Textiles, Donghua University, Shanghai 201620 (China); Huang, Chen, E-mail: hc@dhu.edu.cn [Engineering Research Center of Technical Textiles, Ministry of Education, College of Textiles, Donghua University, Shanghai 201620 (China); Jin, Xiangyu [Engineering Research Center of Technical Textiles, Ministry of Education, College of Textiles, Donghua University, Shanghai 201620 (China)

2016-01-01

A novel type of protein fibers, regenerated collagen fibers (RC) from cattle skin, was prepared through wet-spinning. Due to the combined effect of solvent exchange and subsequent drawing process, the fibers were found to have a grooved surface texture. The grooves provided not only ordered topographical cues, but also increased surface area. Protein content of the RC fibers was confirmed by Fourier Transform infrared spectroscopy (FTIR) and ninhydrin color reaction. The fibers could be readily fabricated into nonwovens or other textiles, owning to their comparable physical properties to other commercialized fibers. Cell growth behavior on RC nonwovens suggested both early adhesion and prompt proliferation. The high moisture regain, good processability, along with the excellent cytocompatibility indicated that the RC fibers and nonwovens developed in this study might offer a good candidate for biomedical and healthcare applications. - Highlights: • Wet-spun regenerated collagen fibers having aligned surface grooves • Comparable physiochemical properties to commercialized fibers • Readily processed into nonwovens • Excellent cytocompatibility with prompt cell adhesion and proliferation.

Mg2+ in the major groove modulates B-DNA structure and dynamics.

Directory of Open Access Journals (Sweden)

Marc Guéroult

Full Text Available This study investigates the effect of Mg(2+ bound to the DNA major groove on DNA structure and dynamics. The analysis of a comprehensive dataset of B-DNA crystallographic structures shows that divalent cations are preferentially located in the DNA major groove where they interact with successive bases of (A/GpG and the phosphate group of 5'-CpA or TpG. Based on this knowledge, molecular dynamics simulations were carried out on a DNA oligomer without or with Mg(2+ close to an ApG step. These simulations showed that the hydrated Mg(2+ forms a stable intra-strand cross-link between the two purines in solution. ApG generates an electrostatic potential in the major groove that is particularly attractive for cations; its intrinsic conformation is well-adapted to the formation of water-mediated hydrogen bonds with Mg(2+. The binding of Mg(2+ modulates the behavior of the 5'-neighboring step by increasing the BII (ε-ζ>0° population of its phosphate group. Additional electrostatic interactions between the 5'-phosphate group and Mg(2+ strengthen both the DNA-cation binding and the BII character of the 5'-step. Cation binding in the major groove may therefore locally influence the DNA conformational landscape, suggesting a possible avenue for better understanding how strong DNA distortions can be stabilized in protein-DNA complexes.

Numerical analysis of lateral illumination lightpipes using elliptical grooves

Science.gov (United States)

Sánchez-Guerrero, Guillermo E.; Viera-González, Perla M.; Martínez-Guerra, Edgar; Ceballos-Herrera, Daniel E.

2017-09-01

Lightpipes are used for illumination in applications such as back-lighting or solar cell concentrators due to the high irradiance uniformity, but its optimal design requires several parameters. This work presents a procedure to design a square lightpipe to control the light-extraction on its lateral face using commercial LEDs placed symmetrically in the lightpipe frontal face. We propose the use of grooves using total internal reflection placed successively in the same face of extraction to control the area of emission. The LED area of emission is small compared with the illuminated area, and, as expected, the lateral face total power is attenuated. These grooves reduce the optical elements in the system and can control areas of illumination. A mathematical and numerical analysis are presented to determine the dependencies on the light-extraction.

Design analysis of a self-acting spiral-groove ring seal for counter-rotating shafts

Science.gov (United States)

Dirusso, E.

1983-01-01

A self-acting spiral groove inter-shaft ring seal of nominal 16.33 cm (6.43 in.) diameter for sealing fan bleed air between counter-rotating hafts in advanced turbofan engines was analyzed. The analysis focused on the lift force characteristics of the spiral grooves. A NASA Lewis developed computer program for predicting the performance of gas lubricated face seals was used to optimize the spiral groove geometry to produce maximum lift force. Load capacity curves (lift force as function of film thickness) were generated for four advanced turbofan engine operating conditions at relative seal speeds ranging from 17,850 to 29,800 rpm, sealed air pressures from 6 to 42 N/sq cm (9 to 60 psi) absolute and temperatures from 95 deg to 327 C (203 deg to 620 F). The relative seal sliding speed range was 152 to 255 m/sec (500 to 836 ft/sec). The analysis showed that the spiral grooves are capable of producing sufficient lift force such that the ring seal will operate in a noncontacting mode over the operating range of typical advanced turbofan engines.

A novel machine learning model to predict abnormal Runway Occupancy Times and observe related precursors

NARCIS (Netherlands)

Herrema, Herrema Floris; Treve, V; Desart, B; Curran, R.; Visser, H.G.

2017-01-01

Accidents on the runway triggered the development and implementation of mitigation strategies. Therefore, the airline industry is moving toward proactive risk management, which aims to identify and predict risk percursors and to mitigate risks before accidents occur. For certain predictions Machine

Hydrodynamic simulations of microjetting from shock-loaded grooves

Science.gov (United States)

Roland, C.; de Rességuier, T.; Sollier, A.; Lescoute, E.; Soulard, L.; Loison, D.

2017-01-01

The interaction of a shock wave with a free surface which has geometrical defects, such as cavities or grooves, may lead to the ejection of micrometric debris at velocities of km/s. This process can be involved in many applications, like pyrotechnics or industrial safety. Recent laser shock experiments reported elsewhere in this conference have provided some insight into jet formation as well as jet tip velocities for various groove angles and shock pressures. Here, we present hydrodynamic simulations of these experiments, in both 2D and 3D geometries, using both finite element method and smoothed particle hydrodynamics. Numerical results are compared to several theoretical predictions including the Richtmyer-Meshkov instabilities. The role of the elastic-plastic behavior on jet formation is illustrated. Finally, the possibility to simulate the late stage of jet expansion and fragmentation is explored, to evaluate the mass distribution of the ejecta and their ballistic properties, still essentially unknown in the experiments.

Treatment of combined endodontic: periodontic lesion by sealing of palato-radicular groove using biodentine

OpenAIRE

Naik, Mayuri; de Ataide, Ida de Noronha; Fernandes, Marina; Lambor, Rajan

2014-01-01

Introduction: Palatoradicular groove is a developmental anomaly which is predominantly found in maxillary lateral incisors. It provides a susceptible alcove for the progression of localised periodontal inflammation which can further cause pulpal involvement. This case report describes the successful treatment of a large periodontic - endodontic lesion usingnon surgical endodontic therapy and biodentine for the sealing of the palatoradicular groove.

Treatment of combined endodontic: periodontic lesion by sealing of palato-radicular groove using biodentine.

Science.gov (United States)

Naik, Mayuri; de Ataide, Ida de Noronha; Fernandes, Marina; Lambor, Rajan

2014-11-01

Palatoradicular groove is a developmental anomaly which is predominantly found in maxillary lateral incisors. It provides a susceptible alcove for the progression of localised periodontal inflammation which can further cause pulpal involvement. This case report describes the successful treatment of a large periodontic - endodontic lesion usingnon surgical endodontic therapy and biodentine for the sealing of the palatoradicular groove.

TR-PIV measurement of the wake behind a grooved cylinder at low Reynolds number

Science.gov (United States)

Liu, Ying Zheng; Shi, Liu Liu; Yu, Jun

2011-04-01

A comparative study of the wakes behind cylinders with grooved and smooth surfaces was performed with a view to understand the wake characteristics associated with the adult Saguaro cacti. A low-speed recirculation water channel was established for the experiment; the Reynolds number, based on the free-stream velocity and cylinder diameter (D), was kept at ReD=1500. State-of-the-art time-resolved particle image velocimetry (TR-PIV) was employed to measure a total of 20 480 realizations of the wake field at a frame rate of 250 Hz, enabling a comprehensive view of the time- and phase-averaged wake pattern. In comparison to the wake behind the smooth cylinder, the length of the recirculation zone behind the grooved cylinder was extended by nearly 18.2%, yet the longitudinal velocity fluctuation intensity was considerably weakened. A global view of the peaked spectrum of the longitudinal velocity component revealed that the intermediate region for the grooved cylinder, which approximately corresponds to the transition region where the shear layer vortices interact, merge and shed before the formation of the Karman-like vortex street, was much wider than that for the smooth one. The unsteady events near St=0.3-0.4 were detected in the intermediate region behind the grooved cylinder, but no such events were found in the smooth cylinder system. Although the formation of the Karman-like vortex street was delayed by about 0.6D downstream for the grooved cylinder, no prominent difference in the vortex street region was found in the far wake for both cylinders. The Proper Orthogonal Decomposition (POD) method was used extensively to decompose the vector and swirling strength fields, which gave a close-up view of the vortices in the near wake. The first two POD modes of the swirling strength clarified the spatio-temporal characteristics of the shear layer vortices behind the grooved cylinder. The small-scale vortices superimposed on the shear layers behind the grooved cylinder

Groove Pancreatitis – A Mimic of Pancreatic and Periampullary Tumors

Directory of Open Access Journals (Sweden)

Sivakami R Pradheepkumar

2017-10-01

Full Text Available Groove Pancreatitis (GP is a rare form of focal chronic pancreatitis involving the pancreatico-duodenal groove (PDG. GP was first described by Becker in 1973. Though, GP has been described so many years ago, it is still unfamiliar among most physicians because of lack of sufficient case studies and clinical similarity of GP to conventional pancreatitis. Imaging based differentiation of GP from other lesions, like pancreatic and periampullary adenocarcinoma is also not possible in all the cases, unless there are typical findings favoring GP. Since, the line of treatment and outcome is totally different in these two conditions, appreciation of the fine differences between these two entities is very significant. Groove pancreatitis is symptomatically treated with medicines and only for patients with continuous and severe symptoms which are not amenable to medical treatment surgical management is considered. Radiological differentiation of GP from pancreatic and periampullary malignancies will help to avoid unnecessary surgery in the initial stages. We report two cases of GP, one of pure and other of segmental form where we found typical imaging features which pointed to the diagnosis of GP with a small discussion about the Computed tomography (CT and Magnetic Resonance Imaging (MRI appearance of this entity as well as its differential diagnosis.

Efficient Excitation of Channel Plasmons in Tailored, UV-Lithography-Defined V-Grooves

DEFF Research Database (Denmark)

Smith, Cameron L. C.; Thilsted, Anil Haraksingh; Garcia-Ortiz, Cesar E.

2014-01-01

We demonstrate the highly efficient (>50%) conversion of freely propagating light to channel plasmon-polaritons (CPPs) in gold V-groove waveguides using compact 1.6 μm long waveguide-termination coupling mirrors. Our straightforward fabrication process, involving UV-lithography and crystallographic...... silicon etching, forms the coupling mirrors innately and ensures exceptional-quality, wafer-scale device production. We tailor the V-shaped profiles by thermal silicon oxidation in order to shift initially wedge-located modes downward into the V-grooves, resulting in well-confined CPPs suitable...

Evaluation of the effect of anode groove pitch to ion beam focusibility on spherical plasma focus diode

Energy Technology Data Exchange (ETDEWEB)

Imanari, K [Oyama National College of Technology (Japan). Department of Electrical Engineering; Jiang, W; Masugata, K; Yatsui, K [Nagaoka Univ. of Technology (Japan). Laboratory of Beam Technology

1997-12-31

A new PIC simulation code was developed to evaluate the effect of anode plasma nonuniformity on LIB focusibility. The plasma nonuniformity was modelled by inducing anode grooves in the code. In the experimental conditions, groove pitch about 2.2 mm and groove width of 1.0 mm, the simulation results are in a good agreement with the observed data. At a groove pitch of 2.4 mm, the local divergence was very small, although the focal length was very long. It was inferred that the focusibility of SPFD will be determined by the z-deflection angle rather than the local divergence angle. Modification of the anode curvature may be advantageous to get a higher power density on the focal point. (author). 6 figs., 3 refs.

Management of endodontic-periodontic lesion of a maxillary lateral incisor with palatoradicular groove

OpenAIRE

Jayshree Ramakrishna Vishwas; Shoeb Yakub Shaikh; Varsha H. Tambe; Fareedi Mukram Ali; Mohammed Mustafa

2014-01-01

Presence of palatal radicular grooves are considered to be an important contributing factor to the development of localized periodontitis, as it favored the accumulation and proliferation of bacterial plaque deep into the periodontium. Pulp involvement could result due to the introduction of bacterial toxins through channels that existed between the root canal system and the groove. Early diagnosis, elimination of inflammation and correction of anatomic complications are the key to a favorabl...

The order of condensation in capillary grooves.

Science.gov (United States)

Rascón, Carlos; Parry, Andrew O; Nürnberg, Robert; Pozzato, Alessandro; Tormen, Massimo; Bruschi, Lorenzo; Mistura, Giampaolo

2013-05-15

We consider capillary condensation in a deep groove of width L. The transition occurs at a pressure p(co)(L) described, for large widths, by the Kelvin equation p(sat) - p(co)(L) = 2σ cosθ/L, where θ is the contact angle at the side walls and σ is the surface tension. The order of the transition is determined by the contact angle of the capped end θcap; it is continuous if the liquid completely wets the cap, and first-order otherwise. When the transition is first-order, corner menisci at the bottom of the capillary lead to a pronounced metastability, determined by a complementary Kelvin equation Δp(L) = 2σ sinθcap/L. On approaching the wetting temperature of the capillary cap, the corner menisci merge and a single meniscus unbinds from the bottom of the groove. Finite-size scaling shifts, crossover behaviour and critical singularities are determined at mean-field level and beyond. Numerical and experimental results showing the continuous nature of condensation for θcap = 0 and the influence of corner menisci on adsorption isotherms are presented.

The order of condensation in capillary grooves

International Nuclear Information System (INIS)

Rascón, Carlos; Parry, Andrew O; Nürnberg, Robert; Pozzato, Alessandro; Tormen, Massimo; Bruschi, Lorenzo; Mistura, Giampaolo

2013-01-01

We consider capillary condensation in a deep groove of width L. The transition occurs at a pressure p co (L) described, for large widths, by the Kelvin equation p sat − p co (L) = 2σcosθ/L, where θ is the contact angle at the side walls and σ is the surface tension. The order of the transition is determined by the contact angle of the capped end θ cap ; it is continuous if the liquid completely wets the cap, and first-order otherwise. When the transition is first-order, corner menisci at the bottom of the capillary lead to a pronounced metastability, determined by a complementary Kelvin equation Δp(L) = 2σsinθ cap /L. On approaching the wetting temperature of the capillary cap, the corner menisci merge and a single meniscus unbinds from the bottom of the groove. Finite-size scaling shifts, crossover behaviour and critical singularities are determined at mean-field level and beyond. Numerical and experimental results showing the continuous nature of condensation for θ cap = 0 and the influence of corner menisci on adsorption isotherms are presented. (fast track communication)

Unusual stress fracture in an adolescent baseball pitcher affecting the trochlear groove of the olecranon

International Nuclear Information System (INIS)

Blake, Joseph J.; Block, John J.; Kan, J.H.; Hannah, Gene A.

2008-01-01

Stress fractures of the proximal ulna are known to occur in throwing athletes. Most cases extend to involve the olecranon, and cases limited to the trochlear groove are rare. In this report we present a 17-year-old elite baseball pitcher with a stress fracture of the trochlear groove of the proximal ulna. Diagnosis was made by demonstration of characteristic signal changes on MRI of the elbow. The fracture occurred at the cortical notch, also known as the pseudodefect of the trochlear groove. This case suggests that the cortical notch serves as an area of weakness predisposing pitchers to development of a stress fracture. (orig.)

78 FR 57213 - Notice of Passenger Facility Charge (PFC) Approvals and Disapprovals

Science.gov (United States)

2013-09-17

... extension north--construction/tunnel construction. Electrical vault. Taxiway H construction. Storm water update. Gulfstream Road/tunnel design. Airfield electrical vault design. Taxiway A design. Taxiway H.... Runway 15R/33L flight kitchen demolition. Runway 15L/33R runway safety area improvements. Future taxiway...

Performance Study of Photovoltaic-Thermal (Pv/T) Solar Collector with ·-Grooved Absorber Plate

International Nuclear Information System (INIS)

Mohd Yusof Othman; Hafidz Ruslan; Kamaruzzaman Sopian; Jin, G.L.

2009-01-01

A hybrid photovoltaic-thermal solar collector has been designed, built and its performance has been studied. The advantage of the collector is that it can generate electricity and heat simultaneously. Photovoltaic module SHARP NE-80E2EA with maximum output power of 80 W was used to generate electricity. The module also acts as heat absorber of the collector. Single pass ·-groove collector made of aluminium sheet with 0.7 mm thickness has been used to collect heat generated. Study was conducted under a designed halogen lamps solar simulator with intensities set at 386 ± 8 Wm -2 and 817 ± 8 Wm -2 . The speed of air passing through the collector was set between (69.6 ± 2.2) x 10 -4 kg/s to (695.8 ± 2.2) x 10 -4 kg/s. The objective of the study is to compare the performance of PV/T collector with and without ·-groove absorber. The study found that the PV/T collector with ·-groove absorber plate has higher efficiency than the PV/T without ·-groove absorber. The electrical and thermal efficiencies are also increased when radiation intensity and speed of air increase. (author)

76 FR 21938 - Potential Environmental Impacts of the Proposed Runway 13 Extension and Associated Actions for...

Science.gov (United States)

2011-04-19

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Potential Environmental Impacts of the Proposed Runway 13 Extension and Associated Actions for the Devils Lake Regional Airport in Devils Lake, ND AGENCY: Federal Aviation Administration (FAA), Department of Transportation (DOT). ACTION...

Study on morphology of high-aspect-ratio grooves fabricated by using femtosecond laser irradiation and wet etching

International Nuclear Information System (INIS)

Chen, Tao; Pan, An; Li, Cunxia; Si, Jinhai; Hou, Xun

2015-01-01

Highlights: • We studied morphologies of silicon grooves fabricated by laser irradiation and wet etching. • We found nano-ripple structures formed on the groove sidewall. • Formations of nano-ripples were due to the formation of standing wave and nanoplanes. • Remaining debris on the groove bottom was removed by KOH etching. - Abstract: Morphologies of high-aspect-ratio silicon grooves fabricated by using femtosecond laser irradiation and selective chemical etching of hydrofluoric acid (HF) were studied. Oxygen was deeply doped into silicon under femtosecond laser irradiation in air, and then the oxygen-doped regions were removed by HF etching to form high-aspect-ratio grooves. After HF etching, periodic nano-ripples which were induced in silicon by femtosecond laser were observed on the groove sidewalls. The ripple orientation was perpendicular or parallel to the laser propagation direction (z direction), which depended on the relative direction between the laser polarization direction and the scanning direction. The formation of nano-ripples with orientations perpendicular to z direction could be attributed to the standing wave generated by the interference of the incident light and the reflected light in z direction. The formation of nano-ripples with orientations parallel to z direction could be attributed to the formation of self-organized periodic nanoplanes (bulk nanogratings) induced by femtosecond laser inside silicon. Materials in the tail portion of laser-induced oxygen doping (LIOD) regions were difficult to be etched by HF solution due to low oxygen concentration. The specimen was etched further in KOH solution to remove remaining materials in LIOD regions and all-silicon grooves were fabricated

Construction method for plant facility

International Nuclear Information System (INIS)

Ito, Arata; Hirono, Hideharu; Kyoda, Shigeru; Hanawa, Minoru; Sato, Hitoshi

1998-01-01

A caisson structure is disposed on a construction site for facilities of nuclear power plants. A digging work is performed below the caisson structure and, simultaneous with the digging work, a construction of a base, construction of plant facilities including a building and installation of plant facility are performed on the caisson structure. Then, the caisson structure is sank together with the structures on a base rock in association with the progress of the digging work and secured on the base rock. When securing them on the base rock, a groove is formed to the base rock along tuyere of the caisson structure so that the tuyere and a ceiling portion of the caisson structure are in direct contact with the base rock. Since the construction for the containing building conducted on the caisson structure is performed simultaneous with the digging work conducted below the caisson structure, the term required for the construction of the plant facilities can greatly reduced. (N.H.)

The origin of Phobos grooves from ejecta launched from impact craters on Mars: Tests of the hypothesis

Science.gov (United States)

Ramsley, Kenneth R.; Head, James W.

2013-01-01

The surface of the martian moon Phobos is characterized by parallel and intersecting grooves that bear resemblance to secondary crater chains observed on planetary surfaces. Murray (2011) has hypothesized that the main groove-forming process on Phobos is the intersection of Phobos with ejecta from primary impact events on Mars to produce chains of secondary craters. The hypothesis infers a pattern of parallel jets of ejecta, either fluidized or solidified, that break into equally-spaced fragments and disperse uniformly along-trajectory during the flight from Mars to Phobos. At the moment of impact with Phobos the dispersed fragments emplace secondary craters that are aligned along strike corresponding to the flight pattern of ejecta along trajectory. The aspects of the characteristics of grooves on Phobos cited by this hypothesis that might be explained by secondary ejecta include: their observed linearity, parallelism, planar alignment, pitted nature, change in character along strike, and a "zone of avoidance" where ejecta from Mars is predicted not to impact (Murray, 2011). To test the hypothesis we plot precise Keplerian orbits for ejecta from Mars (elliptical and hyperbolic with periapsis located below the surface of Mars). From these trajectories we: (1) set the fragment dispersion limits of ejecta patterns required to emplace the more typically well-organized parallel grooves observed in returned images from Phobos; (2) plot ranges of the ejecta flight durations from Mars to Phobos and map regions of exposure; (3) utilize the same exposure map to observe trajectory-defined ejecta exposure shadows; (4) observe hemispheric exposure in response to shorter and longer durations of ejecta flight; (5) assess the viability of ejecta emplacing the large family of grooves covering most of the northern hemisphere of Phobos; and (6) plot the arrival of parallel lines of ejecta emplacing chains of craters at oblique incident angles. We also assess the bulk volume of

Role of minor groove width and hydration pattern on amsacrine interaction with DNA.

Directory of Open Access Journals (Sweden)

Deepak K Jangir

Full Text Available Amsacrine is an anilinoacridine derivative anticancer drug, used to treat a wide variety of malignancies. In cells, amsacrine poisons topoisomerase 2 by stabilizing DNA-drug-enzyme ternary complex. Presence of amsacrine increases the steady-state concentration of these ternary complexes which in turn hampers DNA replication and results in subsequent cell death. Due to reversible binding and rapid slip-out of amsacrine from DNA duplex, structural data is not available on amsacrine-DNA complexes. In the present work, we designed five oligonucleotide duplexes, differing in their minor groove widths and hydration pattern, and examined their binding with amsacrine using attenuated total reflection Fourier transform infrared (ATR-FTIR spectroscopy. Complexes of amsacrine with calf thymus DNA were also evaluated for a comparison. Our results demonstrate for the first time that amsacrine is not a simple intercalator; rather mixed type of DNA binding (intercalation and minor groove takes place between amsacrine and DNA. Further, this binding is highly sensitive towards the geometries and hydration patterns of different minor grooves present in the DNA. This study shows that ligand binding to DNA could be very sensitive to DNA base composition and DNA groove structures. Results demonstrated here could have implication for understanding cytotoxic mechanism of aminoacridine based anticancer drugs and provide directions to modify these drugs for better efficacy and few side-effects.

Experimental study of thermal performance of heat pipe with axial trapezoidal grooves

International Nuclear Information System (INIS)

Suh, Jeong Se; Lee, Woon

2003-01-01

Analysis and experiment are performed to investigate the thermal performance of a heat pipe with axial grooves. The heat pipe was designed in a 6.5 mm I.D., 17 axial trapezoidal grooves, 1000 mm long tube of aluminium, and ammonia as working fluid. A mathematical equations for heat pipe with axial grooves is formulated to obtain the capillary limitation on heat transport rate in a steady state. As a result, heat transport factor of heat pipe has the maximum at the operating temperature of 293K in 0m elevation. As the elevation of heat pipe increases, the heat transport factor of the heat pipe is reduced markedly, comparing with that of horizontal elevation of the heat pipe. It may be considered that such behavior of heat pipe is caused by the working fluid swarmed back to the condenser port due to gravity force and supercooled by a coolant of heat exchanger. Analytical results of heat transport factor are in a good agreement with those of experiment

Factors that Determine Depth Perception of Trapezoids, Windsurfers, Runways

Directory of Open Access Journals (Sweden)

Chia-Huei eTseng

2015-04-01

Full Text Available We report here a windsurfer1 illusion, a naturally occurring trapezoidal illusion in which the small endof the sail viewed at a distance appears to be pointed away from the observer even when it is closer.This naturally occurring illusion is so compelling that observers are unaware of their gross perceptualmisinterpretation of the scene. Four laboratory experiment of this kind of trapezoidal illusion investigatedthe joint effects of retinal orientation, head position, relative motion, and the relative direction ofgravity on automatic depth perception. Observers viewed two adjacent white trapezoids outlined on ablack background rotating back and forth +/- 20 deg on a vertical axis much like the sails of two adjacentwindsurfers. Observers reported which side of the trapezoids (long or short appeared to becloser to them (i.e., in front. The longer edge of the trapezoid was reported in front 76+/-2% of trials(windsurfer effect whether it was on the left or on the right. When the display was rotated 90 deg toproduce a runway configuration, there was a striking asymmetry: the long edge was perceived to bein front 97% when it was on the bottom but only 43% when it was on top (runway effect. The runwayeffect persisted when the head was tilted 90 deg or when displays on the ceiling were viewedfrom the floor. 95% of the variance of the variance in the strikingly different 3D perceptions producedby the same 2D trapezoid image was quantitatively explained by a model that assumes there are justthree additive bias factors that account for perceiving an edge as closer: Implicit linear perspective,lower position on the retina (based on an automatic assumption of viewing from above, and beinglower in world coordinates.

Effect of groove design on mechanical and metallurgical properties of quenched and tempered low alloy abrasion resistant steel welded joints

International Nuclear Information System (INIS)

Sharma, Varun; Shahi, A.S.

2014-01-01

Highlights: • Effect of weld groove design on Q and T steel welded joints is investigated. • Groove design influences heat dissipation characteristics of welded joints. • Double-V groove joint possesses maximum yield strength and UTS. • C-groove joint possesses highest impact energy, both at room temperature and 0 °C. • A wide variation in microhardness exists across different zone of the weldments. - Abstract: Experimental investigations were carried out to study the influence of three different groove designs on mechanical and metallurgical properties of 15 mm thick Q and T (quenched and tempered) steel welded joints. Welding heat input variation corresponding to each joint configuration was kept to a minimal such that the objective of investigating, exclusively, the effect of varied weld volume on the mechanical and metallurgical performance of these joints could be accomplished. Mechanical performance of these joints was evaluated by subjecting them to transverse tensile testing, and Charpy V-notch impact testing of the weld zones at room temperature and 0 °C. The results of this study reveal that among all types of groove formations used for welding, double-V groove joint possessed maximum YS (yield strength) and UTS (ultimate tensile strength), besides maximum strength ratio (YS/UTS) that was followed by U-groove joint and C-groove joint, respectively. However, weld zone tested individually, for the cover as well as the root pass of the C-groove joint possessed highest CVN (Charpy V-notch) values, both at room temperature and 0 °C. Extensive microhardness studies of these weldments showed a wide variation in the microhardness values of the weld zone and the HAZ (heat affected zone). It was concluded that each groove formation/design exerted a significant influence on the heat dissipation characteristics of these joints, which is evident from different morphological features as revealed through optical microscopy. Scanning electron microscopic

Successful surgical management of palatogingival groove using platelet-rich fibrin and guided tissue regeneration: A novel approach

Directory of Open Access Journals (Sweden)

J V Karunakaran

2017-01-01

Full Text Available Palatogingival groove also known as radicularlingual groove is a developmental anomaly involving the lingual surface of the maxillary incisors. They are inconspicuous, funnel-shaped, extend for varying distances on root surface and occur due to infolding of the hertwigs epithelial root sheath. This encourages adherence of microorganisms and plaque to levels significant for pathological changes resulting in endodontic and periodontal lesions. The variations in anatomy of the tooth as a cause of pulp necrosis in teeth of anterior maxillary segment should be considered by the clinician when other etiological factors are ruled out. Recognition of palatogingival groove is critical, especially because of its diagnostic complexity and the problems that may arise if it is not properly interpreted and treated. Regeneration is a new emerging approach in endodontics. Choukroun et al. were among the pioneers for using platelet-rich fibrin (PRF to improve bone healing. PRF is rich in platelet cytokines and growth factors. Numerous techniques have been used to eliminate or seal the groove and regenerate endodontic and periodontal tissues. In this case report of two cases, a novel combination therapy involving ultrasonics, blend of PRF with bone graft, guided tissue regeneration membrane was used in the treatment of a palatogingival groove with an endoperio lesion to ensure arrest of disease progression and promote regeneration. The groove was cleaned and prepared ultrasonically and sealed with a bioactive dentin substitute.

Palato-gingival groove: An innocuous culprit for endo-perio lesion

Directory of Open Access Journals (Sweden)

Rafeza Sultana

2016-09-01

Full Text Available This case report represents the clinical management of tooth with palato-gingival groove in a right maxillary lateral incisor with endo-perio lesion leading to dento-alveolar abscess and sinus tract. The right maxillary lateral incisor was examined clinico-radiographically. On clinical examination, the offending tooth revealed localized swelling and an intraoral draining sinus pointing on the labial gingiva without any evidence of caries, discoloration and trauma. The palatal surface of lateral incisor showed a groove with mild calculus embedded in it. The radiographic examination revealed periapical radiolucency. This case provides an evidence of morphological defect of tooth. Complete clinical and radiological examination and adequate knowledge of such morphological/ developmental defects of teeth are necessary for recognition and identification especially because of their diagnostic complexity and further consequences. 

High quality broadband spatial reflections of slow Rayleigh surface acoustic waves modulated by a graded grooved surface

KAUST Repository

Xu, Yanlong; Peng, Pai

2015-01-01

. The graded grooved surface is structured by drilling one dimensional array of graded grooves with increased depths on a flat surface. We investigate SAW dispersion relations, wave field distribution at several typical SAW wavelengths, and time evolution of a

Prioritizing risks via several expert perspectives with application to runway safety

International Nuclear Information System (INIS)

Rogerson, Ellen C.; Lambert, James H.

2012-01-01

Factor hierarchies have been widely used in the literature to represent the view of an expert of what factors most contribute to reliability or safety. The methods for rating and aggregating the influences across a set of expert-elicited factors to risk or reliability are well known as multiple criteria decision analysis. This paper describes a method for distinguishing levels of risk across a set of locations via the use of multiple factor hierarchies. The method avoids averaging across experts and is thus useful for situations where experts disagree and where an absence of expert consensus on the causative or contributing factors is important information for risk management. A case study demonstrates using seven expert perspectives on the airport-specific factors that can contribute to runway incursions. The results are described for eighty towered airports in the US. The expert perspectives include differing relative emphases across the following set of factors: airport geometry, operations, weather, geography, and days since last safety review. Future work is suggested to include human factors issues as pilot-and-controller communications styles at airports. - Highlights: ► We examine influential factors in seven expert perspectives on the problem domain. ► We assess eighty US airports with qualitative measurement scales for each risk factor. ► Results show robustness and sensitivity of the risk index to expert perspective. ► We examine factors of several types including runway geometry, operations, weather, and geography.

Research on Grooved Concrete Pavement Based on the Durability of Its Anti-Skid Performance

Directory of Open Access Journals (Sweden)

Mulian Zheng

2018-05-01

Full Text Available The objectives of the present study are to investigate the anti-skid performance of concrete pavement and to attempt to enhance its durability by two different methods: using a longitudinally-transversely grooved (LT form, and using a self-developed composite curing agent containing paraffin and Na2SiO3 as the main ingredients. The friction coefficient (μ was measured by self-developed equipment to evaluate the anti-skid performance of samples with three different groove forms (LT, longitudinally grooved (L, and transversely grooved (T. Abrasion tests were then carried out to evaluate the durability of the anti-skid performance. The results indicated that anti-skid performance of LT samples was approximately 46.2% greater than that of T samples, but its durability was not as significant as that of T samples. However, the resistance to abrasion could be improved by using the aforementioned curing agent. Comparisons were carried out between samples sprayed the curing agent and control samples without any curing agent under standard conditions. It was found that the application of the curing agent increased the anti-skid durability of concrete by 35.4%~47.8%, proving it to be a useful and promising technique.

Laser Surface Hardening of Groove Edges

Science.gov (United States)

Hussain, A.; Hamdani, A. H.; Akhter, R.; Aslam, M.

2013-06-01

Surface hardening of groove-edges made of 3Cr13 Stainless Steel has been carried out using 500 W CO2 laser with a rectangular beam of 2.5×3 mm2. The processing speed was varied from 150-500 mm/min. It was seen that the hardened depth increases with increase in laser interaction time. A maximum hardened depth of around 1mm was achieved. The microhardness of the transformed zone was 2.5 times the hardness of base metal. The XRD's and microstructural analysis were also reported.

High quality broadband spatial reflections of slow Rayleigh surface acoustic waves modulated by a graded grooved surface

KAUST Repository

Xu, Yanlong

2015-01-21

We report high quality broadband spatial reflections of Rayleigh surface acoustic waves (SAWs) through a graded grooved surface. High quality means that no wave is allowed to transmit and the incident wave is nearly all reflected to the input side. The graded grooved surface is structured by drilling one dimensional array of graded grooves with increased depths on a flat surface. We investigate SAW dispersion relations, wave field distribution at several typical SAW wavelengths, and time evolution of a Gaussian pulse through the graded grooved surface. Results show that the input broadband Rayleigh SAWs can be slowed, spatially enhanced and stopped, and finally reflected to the input side. The study suggests that engraving the flat surface can be used as an efficient and economical way to manipulate Rayleigh SAWs, which has potential application in novel SAW devices such as filters, reflectors, sensors, energy harvesters, and diodes.

Selenide isotope generator for the Galileo Mission: copper/water axially-grooved heat pipe topical report

International Nuclear Information System (INIS)

Strazza, N.P.

1979-01-01

This report presents a summary of the major accomplishments for the development, fabrication, and testing of axially-grooved copper/water heat pipes for Selenide Isotopic Generator (SIG) applications. The early development consisted of chemical, physical, and analytical studies to define an axially-grooved tube geometry that could be successfully fabricated and provide the desired long term (up to seven years) performance is presented. Heat pipe fabrication procedures, measured performance and accelerated life testing of heat pipes S/Ns AL-5 and LT-57 conducted at B and K Engineering are discussed. S/N AL-5 was the first axially-grooved copper/water heat pipe that was fabricated with the new internal coating process for cupric oxide (CuO) and the cleaning and water preparation methods developed by Battelle Columbus Laboratories. Heat pipe S/N LT-57 was fabricated along with sixty other axially-grooved heat pipes allocated for life testing at Teledyne Energy Systems. As of June 25, 1979, heat pipes S/Ns AL-5 and LT-57 have been accelerated life tested for 13,310 and 6,292 respectively, at a nominal operating temperature of 225 0 C without any signs of thermal performance degradation

Torque scaling in small-gap Taylor-Couette flow with smooth or grooved wall

Science.gov (United States)

Zhu, Bihai; Ji, Zengqi; Lou, Zhengkun; Qian, Pengcheng

2018-03-01

The torque in the Taylor-Couette flow for radius ratios η ≥0.97 , with smooth or grooved wall static outer cylinders, is studied experimentally, with the Reynolds number of the inner cylinder reaching up to Rei=2 ×105 , corresponding to the Taylor number up to Ta =5 ×1010 . The grooves are perpendicular to the mean flow, and similar to the structure of a submersible motor stator. It is found that the dimensionless torque G , at a given Rei and η , is significantly greater for grooved cases than smooth cases. We compare our experimental torques for the smooth cases to the fit proposed by Wendt [F. Wendt, Ing.-Arch. 4, 577 (1993), 10.1007/BF02084936] and the fit proposed by Bilgen and Boulos [E. Bilgen and R. Boulos, J Fluids Eng. 95, 122 (1973), 10.1115/1.3446944], which shows both fits are outside their range for small gaps. Furthermore, an additional dimensionless torque (angular velocity flux) N uω in the smooth cases exhibits an effective scaling of N uω˜T a0.39 in the ultimate regime, which occurs at a lower Taylor number, Ta ≈3.5 ×107 , than the well-explored η =0.714 case (at Ta ≈3 ×108 ). The same effective scaling exponent, 0.39, is also evident in the grooved cases, but for η =0.97 and 0.985, there is a peak before this exponent appears.

75 FR 44047 - Notice of Passenger Facility Charge (PFC) Approvals and Disapprovals

Science.gov (United States)

2010-07-27

... Collection and Use: Relocate runway 3 localizer. Pavement management program--rehabilitate taxiway F. Runway... share. Runway 21 extension--phase 2, pave construct runway only. Pavement management program--mill...

CFD Validation of Gas Injection in Flowing Mercury over Vertical Smooth and Grooved Wall

International Nuclear Information System (INIS)

Abdou, Ashraf A.; Wendel, Mark W.; Felde, David K.; Riemer, Bernie

2009-01-01

The Spallation Neutron Source (SNS) is an accelerator-based neutron source at Oak Ridge National Laboratory (ORNL). The nuclear spallation reaction occurs when a proton beam hits liquid mercury. This interaction causes thermal expansion of the liquid mercury which produces high pressure waves. When these pressure waves hit the target vessel wall, cavitation can occur and erode the wall. Research and development efforts at SNS include creation of a vertical protective gas layer between the flowing liquid mercury and target vessel wall to mitigate the cavitation damage erosion and extend the life time of the target. Since mercury is opaque, computational fluid dynamics (CFD) can be used as a diagnostic tool to see inside the liquid mercury and guide the experimental efforts. In this study, CFD simulations of three dimensional, unsteady, turbulent, two-phase flow of helium gas injection in flowing liquid mercury over smooth, vertically grooved and horizontally grooved walls are carried out with the commercially available CFD code Fluent-12 from ANSYS. The Volume of Fluid (VOF) model is used to track the helium-mercury interface. V-shaped vertical and horizontal grooves with 0.5 mm pitch and about 0.7 mm depth were machined in the transparent wall of acrylic test sections. Flow visualization data of helium gas coverage through transparent test sections is obtained with a high-speed camera at the ORNL target test facility (TTF). The helium gas mass flow rate is 8 mg/min and introduced through a 0.5 mm diameter port. The local mercury velocity is 0.9 m/s. In this paper, the helium gas flow rate and the local mercury velocity are kept constant for the three cases. Time integration of predicted helium gas volume fraction over time is done to evaluate the gas coverage and calculate the average thickness of the helium gas layer. The predicted time-integrated gas coverage over vertically grooved and horizontally grooved test sections is better than over a smooth wall. The

In Vitro Retentive Effect of Groove, Sandblasting, and Cement Type on Stainless Steel Crowns in Primary Molars.

Science.gov (United States)

Pathak, Sidhant; Shashibhushan, K K; Bharath, K P; Poornima, P; Reddy, V V Subba

2015-01-01

The purpose of this study was to evaluate and compare the effect of placing vertical grooves, sandblasting, and luting cements on the retention of stainless steel crowns (SSCs). Eighty extracted primary molars were mounted in acrylic blocks. Specimens were divided into Group 1 (RelyX U200) and Group 2 (Smart Cem2). Teeth in each group were further subdivided into Subgroup A (no vertical grooves and no sandblasting), Subgroup B (vertical grooves), Subgroup C (sandblasting of crowns), and Subgroup D (vertical grooves and sandblasting of crowns). After cementation, SSCs were pulled off using a universal testing machine. One-way analysis of variance was used for statistical analyses. In Groups 1 and 2, the highest retentive strengths were found in Subgroup D (1,124 and 783 kPa, respectively), followed by Subgroup C (1,066 and 748 kPa, respectively), Subgroup A (762 and 356 kPa, respectively), and Subgroup B (743 and 314 kPa, respectively). Retentive strength in Group one was significantly higher than in Group two; Subgroups A and B were significantly lower than C and D. RelyX U200 showed higher retentive strength than Smart Cem2. Sandblasting increased the retention strength, whereas a vertical groove had no significant effect on retention.

Changes in the Albedo of the Pegasus and Phoenix Runways, 2000-2017

Science.gov (United States)

2017-07-18

by the net heat transfer into the runway surface during the brief but intense peak of austral summer. The flux of downwelling shortwave solar energy...snow; and as ERDC/CRREL TR-17-10 2 mentioned above, the presence of melt water in the snow further reduces albedo and increases heating of the snow...interpolating over all possible angles, end member albedo cases (“white sky” and “black sky”) can be modeled . The actual albedo or “blue sky” albedo falls

The Effect of Shoe Sole Tread Groove Depth on the Gait Parameters during Walking on Dry and Slippery Surface

Directory of Open Access Journals (Sweden)

M Ziaei

2012-12-01

Full Text Available Background: Prevention of slipping accidents requires provision of adequate friction through the use of suitable combinations of footwear and underfoot surfaces. Shoe sole tread groove is one of the important factors on friction coefficient during walking. Objective: To measure the effect of different shoe sole tread groove depths and different surfaces on the required quotient of friction (Q, heel strike velocity and occurrence time of ground reaction forces (GRF in stance phase during walking on slippery and dry surfaces. Methods: In this semi-experimental study, 22 healthy men were studied under different conditions. The studied independent variables were shoe groove depths (included 1, 2.5 and 5 mm and type of walking surface (dry and slippery. Biomechanical gait analysis was carried out with 396 single steps. Data were collected by motion analysis system and two force platform. Results: The occurrence time of GRF was significantly faster on dry surface than slippery surface (p<0.01. Q was significantly lower on slippery surface and with groove depths of 1 and 2.5 mm. The highest value of Q was observed with the deepest groove depth of 5 mm. Heel strike velocity did not differ significantly in the 6 conditions tested. Conclusion: Tread groove depth is a significant factor affecting the Q at the shoes-surface interface on dry and slippery floors. It seems that deeper groove is more appropriate for maintaining the stability during walking. The walking surface affects the occurrence time of GRF; the force components occur sooner on the dry than slippery surface.

Liquid phase solvent bonding of plastic microfluidic devices assisted by retention grooves.

Science.gov (United States)

Wan, Alwin M D; Sadri, Amir; Young, Edmond W K

2015-01-01

We report a novel method for achieving consistent liquid phase solvent bonding of plastic microfluidic devices via the use of retention grooves at the bonding interface. The grooves are patterned during the regular microfabrication process, and can be placed at the periphery of a device, or surrounding microfluidic features with open ports, where they effectively mitigate solvent evaporation, and thus substantially reduce poor bond coverage. This method is broadly applicable to a variety of plastics and solvents, and produces devices with high bond quality (i.e., coverage, strength, and microfeature fidelity) that are suitable for studies in physics, chemistry, and cell biology at the microscale.

Getting into the GROOVE: How Building Effective Education Partnerships and Promoting Authentic Student Research through the Girls' Remotely Operated Ocean Vehicle Exploration (GROOVE) Workshop.

Science.gov (United States)

Pelz, M.; Heesemann, M.; Hoeberechts, M.

2017-12-01

This presentation outlines the pilot year of Girls' Remotely Operated Ocean Vehicle Exploration or GROOVE, a hands-on learning program created collaboratively with education partners Ocean Networks Canada and St. Margaret's School (Victoria, BC, Canada). The program features student-led activities, authentic student experiences, clearly outlined learning outcomes, teacher and student self-assessment tools, and curriculum-aligned content. Presented through the lens of STEM, students build a modified Seaperch ROV and explore and research thematic scientific concepts such as buoyancy, electronic circuitry, and deep-sea exploration. Further, students learn engineering skills such as isotropic scaling, soldering, and assembly as they build their ROV. Ocean Networks Canada (ONC), an initiative of the University of Victoria, develops, operates, and maintains cabled ocean observatory systems. These include technologies developed on the world-leading NEPTUNE and VENUS observatories and the ever-expanding network of community observatories in the Arctic and coastal British Columbia. These observatories, large and small, enable communities, users, scientists, teachers, and students to monitor real-time and historical data from the local marine environment from anywhere on the globe. GROOVE, Girls' Remotely Operated Ocean Vehicle Exploration, is ONC's newest educational program and is related to their foundational program K-12 Ocean Sense educational program. This presentation will share our experiences developing, refining, and assessing our efforts to implement GROOVE using a train-the-trainer model aimed at formal and informal K-12 educators. We will highlight lessons learned from multiple perspectives (students, participants, developers, and mentors) with the intent of informing future education and outreach initiatives.

In and out of the minor groove: interaction of an AT-rich DNA with the drug CD27

Energy Technology Data Exchange (ETDEWEB)

Acosta-Reyes, Francisco J. [Universitat Politécnica de Catalunya, Diagonal 647, 08028 Barcelona (Spain); Dardonville, Christophe [Instituto de Química Médica, IQM–CSIC, Juan de la Cierva 3, 28006 Madrid (Spain); Koning, Harry P. de; Natto, Manal [University of Glasgow, 120 University Place, Glasgow G12 8TA, Scotland (United Kingdom); Subirana, Juan A.; Campos, J. Lourdes, E-mail: lourdes.campos@upc.edu [Universitat Politécnica de Catalunya, Diagonal 647, 08028 Barcelona (Spain)

2014-06-01

New features of an antiprotozoal DNA minor-groove binding drug, which acts as a cross-linking agent, are presented. It also fills the minor groove of DNA completely and prevents the access of proteins. These features are also expected for other minor-groove binding drugs when associated with suitable DNA targets. The DNA of several pathogens is very rich in AT base pairs. Typical examples include the malaria parasite Plasmodium falciparum and the causative agents of trichomoniasis and trypanosomiases. This fact has prompted studies of drugs which interact with the minor groove of DNA, some of which are used in medical practice. Previous studies have been performed almost exclusively with the AATT sequence. New features should be uncovered through the study of different DNA sequences. In this paper, the crystal structure of the complex of the DNA duplex d(AAAATTTT){sub 2} with the dicationic drug 4, 4′-bis(imidazolinylamino)diphenylamine (CD27) is presented. The drug binds to the minor groove of DNA as expected, but it shows two new features that have not previously been described: (i) the drugs protrude from the DNA and interact with neighbouring molecules, so that they may act as cross-linking agents, and (ii) the drugs completely cover the whole minor groove of DNA and displace bound water. Thus, they may prevent the access to DNA of proteins such as AT-hook proteins. These features are also expected for other minor-groove binding drugs when associated with all-AT DNA. These findings allow a better understanding of this family of compounds and will help in the development of new, more effective drugs. New data on the biological interaction of CD27 with the causative agent of trichomoniasis, Trichomonas vaginalis, are also reported.

In and out of the minor groove: interaction of an AT-rich DNA with the drug CD27

International Nuclear Information System (INIS)

Acosta-Reyes, Francisco J.; Dardonville, Christophe; Koning, Harry P. de; Natto, Manal; Subirana, Juan A.; Campos, J. Lourdes

2014-01-01

New features of an antiprotozoal DNA minor-groove binding drug, which acts as a cross-linking agent, are presented. It also fills the minor groove of DNA completely and prevents the access of proteins. These features are also expected for other minor-groove binding drugs when associated with suitable DNA targets. The DNA of several pathogens is very rich in AT base pairs. Typical examples include the malaria parasite Plasmodium falciparum and the causative agents of trichomoniasis and trypanosomiases. This fact has prompted studies of drugs which interact with the minor groove of DNA, some of which are used in medical practice. Previous studies have been performed almost exclusively with the AATT sequence. New features should be uncovered through the study of different DNA sequences. In this paper, the crystal structure of the complex of the DNA duplex d(AAAATTTT) 2 with the dicationic drug 4, 4′-bis(imidazolinylamino)diphenylamine (CD27) is presented. The drug binds to the minor groove of DNA as expected, but it shows two new features that have not previously been described: (i) the drugs protrude from the DNA and interact with neighbouring molecules, so that they may act as cross-linking agents, and (ii) the drugs completely cover the whole minor groove of DNA and displace bound water. Thus, they may prevent the access to DNA of proteins such as AT-hook proteins. These features are also expected for other minor-groove binding drugs when associated with all-AT DNA. These findings allow a better understanding of this family of compounds and will help in the development of new, more effective drugs. New data on the biological interaction of CD27 with the causative agent of trichomoniasis, Trichomonas vaginalis, are also reported

Syncopation affects free body-movement in musical groove

DEFF Research Database (Denmark)

Witek, Maria A. G.; Popescu, Tudor; Clarke, Eric F

2016-01-01

One of the most immediate and overt ways in which people respond to music is by moving their bodies to the beat. However, the extent to which the rhythmic complexity of groove-specifically its syncopation-contributes to how people spontaneously move to music is largely unexplored. Here, we measur...... on the body-part. We demonstrate that while people do not move or synchronise much to rhythms with high syncopation when dancing spontaneously to music, the relationship between rhythmic complexity and synchronisation is less linear than in simple finger-tapping studies.......One of the most immediate and overt ways in which people respond to music is by moving their bodies to the beat. However, the extent to which the rhythmic complexity of groove-specifically its syncopation-contributes to how people spontaneously move to music is largely unexplored. Here, we measured...... free movements in hand and torso while participants listened to drum-breaks with various degrees of syncopation. We found that drum-breaks with medium degrees of syncopation were associated with the same amount of acceleration and synchronisation as low degrees of syncopation. Participants who enjoyed...

Selection of pavement foundation geomaterials for the construction of a new runway

CSIR Research Space (South Africa)

Anochie-Boateng, Joseph

2011-07-01

Full Text Available specifications. A comprehensive laboratory testing study was recently conducted at the University of Illinois at Urbana-Champaign to support an expansion project of an international airport in North Carolina. The project involved the construction of a hub... foundation materials. The granular base layers serve a variety of purposes including reducing the stress applied to the subgrade layer and providing drainage for the pavement. This paper presents the engineering properties of three granular materials for a...

Development of an equine groove model to induce metacarpophalangeal osteoarthritis: a pilot study on 6 horses.

Science.gov (United States)

Maninchedda, Ugo; Lepage, Olivier M; Gangl, Monika; Hilairet, Sandrine; Remandet, Bernard; Meot, Francoise; Penarier, Geraldine; Segard, Emilie; Cortez, Pierre; Jorgensen, Christian; Steinberg, Régis

2015-01-01

The aim of this work was to develop an equine metacarpophalangeal joint model that induces osteoarthritis that is not primarily mediated by instability or inflammation. The study involved six Standardbred horses. Standardized cartilage surface damage or "grooves" were created arthroscopically on the distal dorsal aspect of the lateral and medial metacarpal condyles of a randomly chosen limb. The contralateral limb was sham operated. After 2 weeks of stall rest, horses were trotted 30 minutes every other day for 8 weeks, then evaluated for lameness and radiographed. Synovial fluid was analyzed for cytology and biomarkers. At 10 weeks post-surgery, horses were euthanized for macroscopic and histologic joint evaluation. Arthroscopic grooving allowed precise and identical damage to the cartilage of all animals. Under the controlled exercise regime, this osteoarthritis groove model displayed significant radiographic, macroscopic, and microscopic degenerative and reactive changes. Histology demonstrated consistent surgically induced grooves limited to non-calcified cartilage and accompanied by secondary adjacent cartilage lesions, chondrocyte necrosis, chondrocyte clusters, cartilage matrix softening, fissuring, mild subchondral bone inflammation, edema, and osteoblastic margination. Synovial fluid biochemistry and cytology demonstrated significantly elevated total protein without an increase in prostaglandin E2, neutrophils, or chondrocytes. This equine metacarpophalangeal groove model demonstrated that standardized non-calcified cartilage damage accompanied by exercise triggered altered osteochondral morphology and cartilage degeneration with minimal or inefficient repair and little inflammatory response. This model, if validated, would allow for assessment of disease processes and the effects of therapy.

Development of an equine groove model to induce metacarpophalangeal osteoarthritis: a pilot study on 6 horses.

Directory of Open Access Journals (Sweden)

Ugo Maninchedda

Full Text Available The aim of this work was to develop an equine metacarpophalangeal joint model that induces osteoarthritis that is not primarily mediated by instability or inflammation. The study involved six Standardbred horses. Standardized cartilage surface damage or "grooves" were created arthroscopically on the distal dorsal aspect of the lateral and medial metacarpal condyles of a randomly chosen limb. The contralateral limb was sham operated. After 2 weeks of stall rest, horses were trotted 30 minutes every other day for 8 weeks, then evaluated for lameness and radiographed. Synovial fluid was analyzed for cytology and biomarkers. At 10 weeks post-surgery, horses were euthanized for macroscopic and histologic joint evaluation. Arthroscopic grooving allowed precise and identical damage to the cartilage of all animals. Under the controlled exercise regime, this osteoarthritis groove model displayed significant radiographic, macroscopic, and microscopic degenerative and reactive changes. Histology demonstrated consistent surgically induced grooves limited to non-calcified cartilage and accompanied by secondary adjacent cartilage lesions, chondrocyte necrosis, chondrocyte clusters, cartilage matrix softening, fissuring, mild subchondral bone inflammation, edema, and osteoblastic margination. Synovial fluid biochemistry and cytology demonstrated significantly elevated total protein without an increase in prostaglandin E2, neutrophils, or chondrocytes. This equine metacarpophalangeal groove model demonstrated that standardized non-calcified cartilage damage accompanied by exercise triggered altered osteochondral morphology and cartilage degeneration with minimal or inefficient repair and little inflammatory response. This model, if validated, would allow for assessment of disease processes and the effects of therapy.

High Excitation Efficiency of Channel Plasmon Polaritons in Tailored, UV-Lithography-Defined V-Grooves

DEFF Research Database (Denmark)

Smith, Cameron; Thilsted, Anil Haraksingh; Garcia-Ortiz, Cesar E.

2014-01-01

We demonstrate >50% conversion of light to V-groove channel plasmon-polaritons (CPPs) via compact waveguide-termination mirrors. Devices are fabricated using UV-lithography and crystallographic silicon etching. The V-shape is tailored by thermal oxidation to support confined CPPs.......We demonstrate >50% conversion of light to V-groove channel plasmon-polaritons (CPPs) via compact waveguide-termination mirrors. Devices are fabricated using UV-lithography and crystallographic silicon etching. The V-shape is tailored by thermal oxidation to support confined CPPs....

The relationship of transverse sinus stenosis to bony groove dimensions provides an insight into the aetiology of idiopathic intracranial hypertension

Energy Technology Data Exchange (ETDEWEB)

Connor, S.E.J.; Stewart, V.R.; O' Flynn, E.A.M. [King' s College Hospital, Neuroradiology Department, Ruskin Wing, London (United Kingdom); Siddiqui, M.A. [Southern General Hospital, Institute of Neurological Sciences, Glasgow (United Kingdom)

2008-12-15

Transverse sinus tapered narrowings are frequently identified in patients with idiopathic intracranial hypertension (IIH); however, it remains unclear whether they are primary stenoses or whether they occur secondary to raised cerebrospinal fluid pressure. Computed tomographic venography demonstrates both the morphology of the venous system and the adjacent bony grooves so it may provide an insight into the aetiology of these transverse sinus stenoses. Tapered transverse sinus narrowings (>50%) were studied in 19 patients without IIH and 14 patients with IIH. Computed tomography vascular studies were reviewed and the dimensions of the venous sinuses and bony grooves at the sites of maximum and minimum transverse sinus area dimensions were recorded. There was demonstrated to be a strong correlation of bony groove height with venous sinus height at the largest portions of the transverse sinus in both IIH patients and non-IIH subjects as well as at the transverse sinus narrowing in non-IIH subjects. There was a discordant relationship between bony groove height and venous sinus height at the site of transverse sinus stenoses in IIH patients. In 5/23 IIH transverse sinus stenoses, the bony groove height was proportionate to that seen in non-IIH subjects. There were a further 8/23 cases where the small or absent sinus was associated with an absent bony groove. Transverse sinus tapered narrowings in subjects without IIH and in the majority of patients with IIH were associated with proportionately small or absent grooves, and these are postulated to be primary or fixed. Some patients with IIH demonstrate tapered transverse sinus stenoses with disproportionately large bony grooves, suggesting a secondary or acquired narrowing. This implies a varied aetiology for the transverse sinus stenoses of IIH. (orig.)

The relationship of transverse sinus stenosis to bony groove dimensions provides an insight into the aetiology of idiopathic intracranial hypertension

International Nuclear Information System (INIS)

Connor, S.E.J.; Stewart, V.R.; O'Flynn, E.A.M.; Siddiqui, M.A.

2008-01-01

Transverse sinus tapered narrowings are frequently identified in patients with idiopathic intracranial hypertension (IIH); however, it remains unclear whether they are primary stenoses or whether they occur secondary to raised cerebrospinal fluid pressure. Computed tomographic venography demonstrates both the morphology of the venous system and the adjacent bony grooves so it may provide an insight into the aetiology of these transverse sinus stenoses. Tapered transverse sinus narrowings (>50%) were studied in 19 patients without IIH and 14 patients with IIH. Computed tomography vascular studies were reviewed and the dimensions of the venous sinuses and bony grooves at the sites of maximum and minimum transverse sinus area dimensions were recorded. There was demonstrated to be a strong correlation of bony groove height with venous sinus height at the largest portions of the transverse sinus in both IIH patients and non-IIH subjects as well as at the transverse sinus narrowing in non-IIH subjects. There was a discordant relationship between bony groove height and venous sinus height at the site of transverse sinus stenoses in IIH patients. In 5/23 IIH transverse sinus stenoses, the bony groove height was proportionate to that seen in non-IIH subjects. There were a further 8/23 cases where the small or absent sinus was associated with an absent bony groove. Transverse sinus tapered narrowings in subjects without IIH and in the majority of patients with IIH were associated with proportionately small or absent grooves, and these are postulated to be primary or fixed. Some patients with IIH demonstrate tapered transverse sinus stenoses with disproportionately large bony grooves, suggesting a secondary or acquired narrowing. This implies a varied aetiology for the transverse sinus stenoses of IIH. (orig.)

Behavior of aircraft antiskid braking systems on dry and wet runway surfaces. A slip-velocity-controlled, pressure-bias-modulated system

Science.gov (United States)

Stubbs, S. M.; Tanner, J. A.; Smith, E. G.

1979-01-01

The braking and cornering response of a slip velocity controlled, pressure bias modulated aircraft antiskid braking system is investigated. The investigation, conducted on dry and wet runway surfaces, utilized one main gear wheel, brake, and tire assembly of a McDonnell Douglas DC 9 series 10 airplane. The landing gear strut was replaced by a dynamometer. The parameters, which were varied, included the carriage speed, tire loading, yaw angle, tire tread condition, brake system operating pressure, and runway wetness conditions. The effects of each of these parameters on the behavior of the skid control system is presented. Comparisons between data obtained with the skid control system and data obtained from single cycle braking tests without antiskid protection are examined.

Effect of nitrogen-doped graphene nanofluid on the thermal performance of the grooved copper heat pipe

DEFF Research Database (Denmark)

Mehrali, Mohammad; Sadeghinezhad, Emad; Azizian, Reza

2016-01-01

Thermal performance of a grooved heat pipe using aqueous nitrogen-doped graphene (NDG) nanofluids was analysed. This study in particular focused on the effect of varying NDG nanosheets concentrations, heat pipe inclination angles and input heating powers. The results indicated that the inclination...... observed for NDG nanofluid with concentration of 0.06wt%, inclination angle of θ=90° and a heating power of 120W in comparison to DI-water under the exact same condition. Additionally, the surface temperature distribution was decreased by employing NDG nanosheets, which can in return increase the thermal...... performance of a grooved heat pipe. The present investigation indicated that the thermal performance of the grooved heat pipe can be improved significantly by using NDG nanofluids....

Influence of structural parameters of deep groove ball bearings on vibration

Science.gov (United States)

Yu, Guangwei; Wu, Rui; Xia, Wei

2018-04-01

Taking 6201 bearing as the research object, a dynamic model of 4 degrees of freedom is established to solve the vibration characteristics such as the displacement, velocity and acceleration of deep groove ball bearings by MATLAB and Runge-Kutta method. By calculating the theoretical value of the frequency of the rolling element passing through the outer ring and the simulation value of the model, it can be known that the theoretical calculation value and the simulation value have good consistency. By the experiments, the measured values and simulation values are consistent. Using the mathematical model, the effect of structural parameters on vibration is obtained. The method in the paper is testified to be feasible and the results can be used as references for the design, manufacturing and testing of deep groove ball bearings.

Observations on the effects of grooved surfaces on the interfacial torque in highly loaded rolling and sliding tests

DEFF Research Database (Denmark)

Janakiraman, Shravan; Klit, Peder; Jensen, Niels Steenfeldt

2014-01-01

Some efforts have been undertaken to study the effects of grooved surfaces on the interfacial film thickness and torque between two contacting non-conformal surfaces under heavy loads. Transverse grooves of micrometer scale depth were engraved on polished, flat ring surfaces using established ind...

Grooved stone tools from Calabria region (Italy: Archaeological evidence and research perspectives

Directory of Open Access Journals (Sweden)

Felice Larocca

2016-10-01

Full Text Available Since the end of the 19th century the Calabria region in southern Italy has been known for an abundance of grooved stone axes and hammers used during late prehistory. These artefacts are characterized by a wide and often pronounced groove in the middle of the implement, thought to have aided securing the head to a wooden haft. Their widespread presence is known both in prehistoric archaeological literature and in the archaeological collections of various regional and extra-regional museums. At first, scholars did not relate these tools to the rich Calabrian ore deposits and to possible ancient mining activities; they were regarded simply as a variant of ground lithic industry of Neolithic tradition. However, between 1997 and 2012, about 50 tools were discovered in the prehistoric mine of Grotta della Monaca in northern Calabria where there are outcrops of copper and iron ore. This allowed us to recognize their specific mining value and to consider them as a sort of “guide fossil” for the identification of ancient mining districts. This paper presents the results of a study involving over 150 tools from the entire region, effectively demonstrating an almost perfect co-occurrence of grooved axes and hammers with areas rich in mineral resources, especially metalliferous ores.

Quantum spill-out in few-nanometer metal gaps: Effect on gap plasmons and reflectance from ultrasharp groove arrays

DEFF Research Database (Denmark)

Skjølstrup, Enok Johannes Haahr; Søndergaard, Thomas; Pedersen, Thomas Garm

2018-01-01

Plasmons in ultranarrow metal gaps are highly sensitive to the electron density profile at the metal surfaces. Using a quantum mechanical approach and assuming local response, we study the effects of electron spill-out on gap plasmons and reflectance from ultrasharp metal grooves.We demonstrate...... the reflectance from arrays of ultrasharp metal grooves. These findings are explained in terms of enhanced gap plasmon absorption taking place inside the gap 1–2 °A from the walls and delocalization near the groove bottom. Reflectance calculations taking spill-out into account are shown to be in much better...

The location of the peroneus longus tendon in the cuboid groove: sonographic study in various positions of the ankle-foot in asymptomatic volunteers.

Science.gov (United States)

Choo, Hye Jung; Lee, Sun Joo; Huang, Brady K; Resnick, Donald L

2018-04-10

To evaluate the normal location of the peroneus longus tendon (PL) in the cuboid groove in various ankle-foot positions by ultrasonography in asymptomatic volunteers. Ultrasonographic assessment of the PL in the cuboid groove was performed in 20 feet of ten healthy volunteers. Each PL was examined in five ankle-foot positions (i.e., neutral, dorsiflexion, plantar-flexion, supination, and pronation). The PL location was qualitatively categorized as "inside" when the PL was entirely within the cuboid groove, as "overlying" when some part of the PL was perched on the cuboid tuberosity, and as "outside" when the PL was entirely on the cuboid tuberosity. For quantitative evaluation of the PL location, the distance between the PL and the cuboid groove was measured. The width of the cuboid groove was measured in the neutral position. The PL location did not significantly change with changes in the ankle-foot position. Qualitatively, an "overlying" PL was the most common type, regardless of the ankle-foot position. "Inside" PLs were found in only 35, 20, 30, 25, and 35% of feet in neutral, dorsiflexion, plantar-flexion, supination, and pronation positions, respectively. The quantitative PL location was also not significantly different among all ankle-foot positions and it was significantly negatively correlated with the cuboid groove width. In healthy volunteers, 65% or more of the PLs were partially or completely located outside of the cuboid groove, regardless of the ankle-foot position. The PL location relative to the cuboid groove was related to the cuboid groove width.

Exact and Heuristic Algorithms for Runway Scheduling

Science.gov (United States)

Malik, Waqar A.; Jung, Yoon C.

2016-01-01

This paper explores the Single Runway Scheduling (SRS) problem with arrivals, departures, and crossing aircraft on the airport surface. Constraints for wake vortex separations, departure area navigation separations and departure time window restrictions are explicitly considered. The main objective of this research is to develop exact and heuristic based algorithms that can be used in real-time decision support tools for Air Traffic Control Tower (ATCT) controllers. The paper provides a multi-objective dynamic programming (DP) based algorithm that finds the exact solution to the SRS problem, but may prove unusable for application in real-time environment due to large computation times for moderate sized problems. We next propose a second algorithm that uses heuristics to restrict the search space for the DP based algorithm. A third algorithm based on a combination of insertion and local search (ILS) heuristics is then presented. Simulation conducted for the east side of Dallas/Fort Worth International Airport allows comparison of the three proposed algorithms and indicates that the ILS algorithm performs favorably in its ability to find efficient solutions and its computation times.

Binding to the minor groove of the double-strand, tau protein prevents DNA from damage by peroxidation.

Science.gov (United States)

Wei, Yan; Qu, Mei-Hua; Wang, Xing-Sheng; Chen, Lan; Wang, Dong-Liang; Liu, Ying; Hua, Qian; He, Rong-Qiao

2008-07-02

Tau, an important microtubule associated protein, has been found to bind to DNA, and to be localized in the nuclei of both neurons and some non-neuronal cells. Here, using electrophoretic mobility shifting assay (EMSA) in the presence of DNA with different chain-lengths, we observed that tau protein favored binding to a 13 bp or a longer polynucleotide. The results from atomic force microscopy also showed that tau protein preferred a 13 bp polynucleotide to a 12 bp or shorter polynucleotide. In a competitive assay, a minor groove binder distamycin A was able to replace the bound tau from the DNA double helix, indicating that tau protein binds to the minor groove. Tau protein was able to protect the double-strand from digestion in the presence of DNase I that was bound to the minor groove. On the other hand, a major groove binder methyl green as a negative competitor exhibited little effect on the retardation of tau-DNA complex in EMSA. This further indicates the DNA minor groove as the binding site for tau protein. EMSA with truncated tau proteins showed that both the proline-rich domain (PRD) and the microtubule-binding domain (MTBD) contributed to the interaction with DNA; that is to say, both PRD and MTBD bound to the minor groove of DNA and bent the double-strand, as observed by electron microscopy. To investigate whether tau protein is able to prevent DNA from the impairment by hydroxyl free radical, the chemiluminescence emitted by the phen-Cu/H(2)O(2)/ascorbate was measured. The emission intensity of the luminescence was markedly decreased when tau protein was present, suggesting a significant protection of DNA from the damage in the presence of hydroxyl free radical.

Design analysis of a self-acting spiral-groove ring seal for counter-rotating shafts. [o ring seals

Science.gov (United States)

Dirusso, E.

1983-01-01

A self-acting spiral groove inter-shaft ring seal of nominal 16.33 cm (6.43 in.) diameter for sealing fan bleed air between counter rotating shafts in advanced turbofan engines was analyzed. The analysis focused on the lift force characteristics of the spiral grooves. A NASA Lewis developed computer program for predicting the performance of gas lubricated face seals was used to optimize the spiral groove geometry to produce maximum lift force. Load capacity curves (lift force as function of film thickness) were generated for four advanced turbofan engine operating conditions at relative seal speeds ranging from 17,850 to 29,800 rpm, sealed air pressures from 6 to 42 N/sq cm (9 to 60 psi) absolute and temperatures from 95 to 327 C (203 to 620 F). The relative seal sliding speed range was 152 to 255 m/sec (500 to 836 ft/sec). The analysis showed that the spiral grooves are capable of producing sufficient lift force such that the ring seal will operate in a noncontacting mode over the operating range of typical advanced turbofan engines.

Modeling and simulation of stamp deflections in nanoimprint lithography: Exploiting backside grooves to enhance residual layer thickness uniformity

DEFF Research Database (Denmark)

Taylor, Hayden; Smistrup, Kristian; Boning, Duane

2011-01-01

We describe a model for the compliance of a nanoimprint stamp etched with a grid of backside grooves. We integrate the model with a fast simulation technique that we have previously demonstrated, to show how etched grooves help reduce the systematic residual layer thickness (RLT) variations...

Effects of scaffold surface morphology on cell adhesion and survival rate in vitreous cryopreservation of tenocyte-scaffold constructs

Energy Technology Data Exchange (ETDEWEB)

Wang, Zhi [State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, Chengdu 610041 (China); Department of Bone and Joint Surgery, The affiliated hospital of Luzhou Medical College, Luzhou 646000 (China); Qing, Quan [Sichuan College of Traditional Chinese Medicine, Mianyang 621000 (China); Regenerative Medicine Research Center, West China Hospital of Sichuan University, Chengdu 610041 (China); Chen, Xi; Liu, Cheng-Jun; Luo, Jing-Cong [State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, Chengdu 610041 (China); Hu, Jin-Lian [Institute of Textiles and Clothing, The Hong Kong Polytechnic University, Hong Kong (China); Qin, Ting-Wu, E-mail: tingwuqin@hotmail.com [State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, Chengdu 610041 (China)

2016-12-01

Highlights: • The shapes of tenocytes varied when seeded on different surface of scaffolds. • Tenocytes were flat on smooth surface and spindle on micro-grooved surface. • Tenocytes were ellipse or spindle on porous surface. • Tenocytes got varying adhesion shape and elongation index on varying surfaces. • The tenocyte survival on porous surface was superior to the other two groups. - Abstract: The purpose of this study was to investigate the effects of scaffold surface morphology on cell adhesion and survival rate in vitreous cryopreservation of tenocyte-scaffold constructs. Tenocytes were obtained from tail tendons of rats. Polydimethylsiloxane (PDMS) was used to fabricate three types of scaffolds with varying surface morphological characteristics, i.e., smooth, micro-grooved, and porous surfaces, respectively. The tenocytes were seeded on the surfaces of the scaffolds to form tenocyte-scaffold constructs. The constructs were cryopreserved in a vitreous cryoprotectant (CPA) with a multi-step protocol. The cell adhesion to scaffolds was observed with electronic scanning microscopy (SEM). The elongation index of the living tenocytes and ratio of live/dead cell number were examined based on a live/dead dual fluorescent staining technique, and the survival rate of tenocytes was studied with flow cytometry (FC). The results showed the shapes of tenocytes varied between the different groups: flat or polygonal (on smooth surface), spindle (on micro-grooved surface), and spindle or ellipse (on porous surface). After thawing, the porous surface got the most living tenocytes and a higher survival rate, suggesting its potential application for vitreous cryopreservation of engineered tendon constructs.

Space qualification of high capacity grooved heat pipes

Energy Technology Data Exchange (ETDEWEB)

Dubois, M; Mullender, B; Druart, J [SABCA, Societe Anomyme Belgel de Construction Aeronautique (Belgium); Supper, W; Beddows, A [ESTEC-The (Netherlands)

1997-12-31

Based on the thermal requirements of the future telecommunication satellites, the development of a High Capacity Grooved Heat Pipe (HPG), was contracted by ESA to SABCA leading to an aluminium extruded heat pipe (outer diameter of 25 mm) based on a multi re-entrant grooves design. After an intensive acceptance test campaign whose results showed a good confidence in the design and the fulfillment of the required specifications of heat transport and on tilt capability (experimental maximum heat transport capability of 1500 Watt metres for a vapour temperature of 20 deg C), similar heat pipes have been developed with various outer diameters (11 mm, 15 mm and 20 mm) and with various shapes (circular outer shapes, integrated saddles). Several of these heat pipes were tested during two parabolic flight campaigns, by varying the heat loads during the micro-gravity periods. This HGP heat pipe family is now being submitted to a space qualification program according to ESA standards (ESA PSS-49), both in straight and bent configuration. Within this qualification, the heat pipes are submitted to an extended test campaign including environmental (random/sinus vibration, constant acceleration) and thermal tests (thermal performance, thermal cycle, thermal soak, ageing). (authors) 9 refs.

Space qualification of high capacity grooved heat pipes

Energy Technology Data Exchange (ETDEWEB)

Dubois, M.; Mullender, B.; Druart, J. [SABCA, Societe Anomyme Belgel de Construction Aeronautique (Belgium); Supper, W.; Beddows, A. [ESTEC-The (Netherlands)

1996-12-31

Based on the thermal requirements of the future telecommunication satellites, the development of a High Capacity Grooved Heat Pipe (HPG), was contracted by ESA to SABCA leading to an aluminium extruded heat pipe (outer diameter of 25 mm) based on a multi re-entrant grooves design. After an intensive acceptance test campaign whose results showed a good confidence in the design and the fulfillment of the required specifications of heat transport and on tilt capability (experimental maximum heat transport capability of 1500 Watt metres for a vapour temperature of 20 deg C), similar heat pipes have been developed with various outer diameters (11 mm, 15 mm and 20 mm) and with various shapes (circular outer shapes, integrated saddles). Several of these heat pipes were tested during two parabolic flight campaigns, by varying the heat loads during the micro-gravity periods. This HGP heat pipe family is now being submitted to a space qualification program according to ESA standards (ESA PSS-49), both in straight and bent configuration. Within this qualification, the heat pipes are submitted to an extended test campaign including environmental (random/sinus vibration, constant acceleration) and thermal tests (thermal performance, thermal cycle, thermal soak, ageing). (authors) 9 refs.

Capillary contact angle in a completely wet groove.

Science.gov (United States)

Parry, A O; Malijevský, A; Rascón, C

2014-10-03

We consider the phase equilibria of a fluid confined in a deep capillary groove of width L with identical side walls and a bottom made of a different material. All walls are completely wet by the liquid. Using density functional theory and interfacial models, we show that the meniscus separating liquid and gas phases at two phase capillary coexistence meets the bottom capped end of the groove at a capillary contact angle θ(cap)(L) which depends on the difference between the Hamaker constants. If the bottom wall has a weaker wall-fluid attraction than the side walls, then θ(cap) > 0 even though all the isolated walls are themselves completely wet. This alters the capillary condensation transition which is now first order; this would be continuous in a capped capillary made wholly of either type of material. We show that the capillary contact angle θ(cap)(L) vanishes in two limits, corresponding to different capillary wetting transitions. These occur as the width (i) becomes macroscopically large, and (ii) is reduced to a microscopic value determined by the difference in Hamaker constants. This second wetting transition is characterized by large scale fluctuations and essential critical singularities arising from marginal interfacial interactions.

Minor-Groove Binding Drugs: Where Is the Second Hoechst 33258 Molecule?

KAUST Repository

Fornander, Louise H.; Wu, Lisha; Billeter, Martin; Lincoln, Per; Nordé n, Bengt

2013-01-01

Hoechst 33258 binds with high affinity into the minor groove of AT-rich sequences of double-helical DNA. Despite extensive studies of this and analogous DNA binding molecules, there still remains uncertainty concerning the interactions when multiple ligand molecules are accommodated within close distance. Albeit not of direct concern for most biomedical applications, which are at low drug concentrations, interaction studies for higher drug binding are important as they can give fundamental insight into binding mechanisms and specificity, including drug self-stacking interactions that can provide base-sequence specificity. Using circular dichroism (CD), isothermal titration calorimetry (ITC), and proton nuclear magnetic resonance (1H NMR), we examine the binding of Hoechst 33258 to three oligonucleotide duplexes containing AT regions of different lengths: [d(CGCGAATTCGCG)]2 (A2T2), [d(CGCAAATTTGCG)]2 (A3T 3), and [d(CGAAAATTTTCG)]2 (A4T4). We find similar binding geometries in the minor groove for all oligonucleotides when the ligand-to-duplex ratio is less than 1:1. At higher ratios, a second ligand can be accommodated in the minor groove of A4T4 but not A2T2 or A3T3. We conclude that the binding of the second Hoechst to A4T4 is not cooperative and that the molecules are sitting with a small separation apart, one after the other, and not in a sandwich structure as previously proposed. © 2013 American Chemical Society.

Minor-Groove Binding Drugs: Where Is the Second Hoechst 33258 Molecule?

KAUST Repository

Fornander, Louise H.

2013-05-16

Hoechst 33258 binds with high affinity into the minor groove of AT-rich sequences of double-helical DNA. Despite extensive studies of this and analogous DNA binding molecules, there still remains uncertainty concerning the interactions when multiple ligand molecules are accommodated within close distance. Albeit not of direct concern for most biomedical applications, which are at low drug concentrations, interaction studies for higher drug binding are important as they can give fundamental insight into binding mechanisms and specificity, including drug self-stacking interactions that can provide base-sequence specificity. Using circular dichroism (CD), isothermal titration calorimetry (ITC), and proton nuclear magnetic resonance (1H NMR), we examine the binding of Hoechst 33258 to three oligonucleotide duplexes containing AT regions of different lengths: [d(CGCGAATTCGCG)]2 (A2T2), [d(CGCAAATTTGCG)]2 (A3T 3), and [d(CGAAAATTTTCG)]2 (A4T4). We find similar binding geometries in the minor groove for all oligonucleotides when the ligand-to-duplex ratio is less than 1:1. At higher ratios, a second ligand can be accommodated in the minor groove of A4T4 but not A2T2 or A3T3. We conclude that the binding of the second Hoechst to A4T4 is not cooperative and that the molecules are sitting with a small separation apart, one after the other, and not in a sandwich structure as previously proposed. © 2013 American Chemical Society.

Disk in a groove with friction: An analysis of static equilibrium and indeterminacy

Science.gov (United States)

Donolato, Cesare

2018-05-01

This note studies the statics of a rigid disk placed in a V-shaped groove with frictional walls and subjected to gravity and a torque. The two-dimensional equilibrium problem is formulated in terms of the angles that contact forces form with the normal to the walls. This approach leads to a single trigonometric equation in two variables whose domain is determined by Coulomb's law of friction. The properties of solutions (existence, uniqueness, or indeterminacy) as functions of groove angle, friction coefficient and applied torque are derived by a simple geometric representation. The results modify some of the conclusions by other authors on the same problem.

Performance of an inclined solar still with rectangular grooves and ridges

International Nuclear Information System (INIS)

Anburaj, P.; Kalidasa, Murugavel K.; Samuel Hansen, R.

2013-01-01

This work investigates the experimental performance of a new type inclined solar still with rectangular grooves and ridges in absorber plate. The still was fabricated and tested for various inclination angles of 25, 30 and 35 facing south with absorber plate. Performances of the still were compared with different wick materials (Black cotton cloth, Jute cloth, and Waste cotton pieces) on the absorber plate. The effect of placing porous material (Clay pot) and energy storing material (Mild steel pieces) in the grooves were studied. The results demonstrate that 30 inclination is optimum which yielded 3.77 L/day production. Compared to different wick materials, black cotton cloth helps to achieve maximum productivity of 4.21 L/day. The addition of permeable materials and energy absorbing materials also enhances the distillate output to 4.27 L/day. (authors)

Aptamer sensor for cocaine using minor groove binder based energy transfer.

Science.gov (United States)

Zhou, Jinwen; Ellis, Amanda V; Kobus, Hilton; Voelcker, Nicolas H

2012-03-16

We report on an optical aptamer sensor for cocaine detection. The cocaine sensitive fluorescein isothiocyanate (FITC)-labeled aptamer underwent a conformational change from a partial single-stranded DNA with a short hairpin to a double-stranded T-junction in the presence of the target. The DNA minor groove binder Hoechst 33342 selectively bound to the double-stranded T-junction, bringing the dye within the Förster radius of FITC, and therefore initiating minor groove binder based energy transfer (MBET), and reporting on the presence of cocaine. The sensor showed a detection limit of 0.2 μM. The sensor was also implemented on a carboxy-functionalized polydimethylsiloxane (PDMS) surface by covalently immobilizing DNA aptamers. The ability of surface-bound cocaine detection is crucial for the development of microfluidic sensors. Copyright © 2012 Elsevier B.V. All rights reserved.

Productive urbanisms : From Runways to Greenways

Energy Technology Data Exchange (ETDEWEB)

White, M [Toronto Univ., ON (Canada). Faculty of Architecture Landscape and Design; Sheppard, L [Waterloo Univ., Cambridge, ON (Canada). School of Architecture

2009-07-01

This paper reported on an international competition for urban development in Reykjavik, Iceland in 2007. Known as the Runways to Greenways proposal, the prototype depends on a strategy that considers energy use, ecology and land use when integrating public amenities. While Iceland is advanced in terms of its vast geothermal reserves, it is a country that uses the most energy per capita. There are 5 major geothermal power plants in Iceland which produce about 26 per cent of the country's electricity. Geothermal heating also meets the heating and hot water needs for nearly 87 per cent of the nation's buildings. However, Reykjavik continues to rely heavily on imported fossil fuel primarily for fishing, transport and heavy industries. A recent masterplan for the expansion of Reykjavik calls for the densification of the city. The objective was to propose a city that is self-sufficient in terms of energy, agriculture and water while addressing the development potentials of biotechnology and ecotechnology enterprises in Reykjavik. The integrated infrastructure calls for a symbiotic relationship between urbanism and nature, and between energy consumption and production in an effort to pair infrastructure, landscape, public infrastructure and architecture in a culturally, economically and environmentally productive urban realm. 9 refs., 12 figs.

Productive urbanisms : From Runways to Greenways

Energy Technology Data Exchange (ETDEWEB)

White, M. [Toronto Univ., ON (Canada). Faculty of Architecture Landscape and Design; Sheppard, L. [Waterloo Univ., Cambridge, ON (Canada). School of Architecture

2009-07-01

This paper reported on an international competition for urban development in Reykjavik, Iceland in 2007. Known as the Runways to Greenways proposal, the prototype depends on a strategy that considers energy use, ecology and land use when integrating public amenities. While Iceland is advanced in terms of its vast geothermal reserves, it is a country that uses the most energy per capita. There are 5 major geothermal power plants in Iceland which produce about 26 per cent of the country's electricity. Geothermal heating also meets the heating and hot water needs for nearly 87 per cent of the nation's buildings. However, Reykjavik continues to rely heavily on imported fossil fuel primarily for fishing, transport and heavy industries. A recent masterplan for the expansion of Reykjavik calls for the densification of the city. The objective was to propose a city that is self-sufficient in terms of energy, agriculture and water while addressing the development potentials of biotechnology and ecotechnology enterprises in Reykjavik. The integrated infrastructure calls for a symbiotic relationship between urbanism and nature, and between energy consumption and production in an effort to pair infrastructure, landscape, public infrastructure and architecture in a culturally, economically and environmentally productive urban realm. 9 refs., 12 figs.

Synthesis and characterization of DNA minor groove binding alkylating agents.

Science.gov (United States)

Iyer, Prema; Srinivasan, Ajay; Singh, Sreelekha K; Mascara, Gerard P; Zayitova, Sevara; Sidone, Brian; Fouquerel, Elise; Svilar, David; Sobol, Robert W; Bobola, Michael S; Silber, John R; Gold, Barry

2013-01-18

Derivatives of methyl 3-(1-methyl-5-(1-methyl-5-(propylcarbamoyl)-1H-pyrrol-3-ylcarbamoyl)-1H-pyrrol-3-ylamino)-3-oxopropane-1-sulfonate (1), a peptide-based DNA minor groove binding methylating agent, were synthesized and characterized. In all cases, the N-terminus was appended with an O-methyl sulfonate ester, while the C-terminus group was varied with nonpolar and polar side chains. In addition, the number of pyrrole rings was varied from 2 (dipeptide) to 3 (tripeptide). The ability of the different analogues to efficiently generate N3-methyladenine was demonstrated as was their selectivity for minor groove (N3-methyladenine) versus major groove (N7-methylguanine) methylation. Induced circular dichroism studies were used to measure the DNA equilibrium binding properties of the stable sulfone analogues; the tripeptide binds with affinity that is >10-fold higher than that of the dipeptide. The toxicities of the compounds were evaluated in alkA/tag glycosylase mutant E. coli and in human WT glioma cells and in cells overexpressing and under-expressing N-methylpurine-DNA glycosylase, which excises N3-methyladenine from DNA. The results show that equilibrium binding correlates with the levels of N3-methyladenine produced and cellular toxicity. The toxicity of 1 was inversely related to the expression of MPG in both the bacterial and mammalian cell lines. The enhanced toxicity parallels the reduced activation of PARP and the diminished rate of formation of aldehyde reactive sites observed in the MPG knockdown cells. It is proposed that unrepaired N3-methyladenine is toxic due to its ability to directly block DNA polymerization.

The magnetic domain structures of Fe thin films on rectangular land-and-groove substrates studied by spin-polarized secondary electron microscopy

Energy Technology Data Exchange (ETDEWEB)

Ueda, S. [Photodynamics Research Center, RIKEN, Aoba-ku, Sendai 980-0845 (Japan)]. E-mail: uedas@postman.riken.go.jp; Iwasaki, Y. [Photodynamics Research Center, RIKEN, Aoba-ku, Sendai 980-0845 (Japan); Micro Systems Network Company, Sony Corporation, Tagajo, Miyagi 985-0842 (Japan); Ushioda, S. [Photodynamics Research Center, RIKEN, Aoba-ku, Sendai 980-0845 (Japan); Research Institute of Electrical Communication, Tohoku University, Aoba-ku, Sendai 980-8577 (Japan)

2004-10-01

The magnetic domain structures of Fe thin films on rectangular land-and-groove structures have been studied by spin-polarized secondary electron microscopy (SP-SEM) under an applied dc field. The coercive force on the land area was found to be higher than that on the groove area in the magnetization reversal due to the difference in surface roughness between land and groove areas. The magnetic domain structure and domain wall pinning behavior during the reversal process depended on the direction of the magnetic field relative to the rectangles. These results show that the anisotropy induced by film geometry also contributes to the magnetization reversal process of thin magnetic films on land{sub a}nd{sub g}roove substrates.

Design and experimental study of a micro-groove grinding wheel with spray cooling effect

Directory of Open Access Journals (Sweden)

Shi Chaofeng

2014-04-01

Full Text Available The effectiveness of grinding fluid supply has a crucial impact on grinding quality and efficiency in high speed grinding. In order to improve the cooling and lubrication, through in-depth research of self-inhaling internal cooling method and intermittent grinding mechanism, a new spray cooling method used in high speed grinding is proposed. By referring to the structure of bowl-shaped dispersion disk, the grinding wheel matrix with atomization ability is designed; through studying heat transfer of droplet collision and the influence of micro-groove on the boiling heat transfer, grinding segment with micro-groove is designed to enhance the heat flux of coolant and achieve maximum heat transfer between droplets and grinding contact zone. High-speed grinding experiments on GH4169 with the developed grinding wheel are carried out. The results show that with the micro-groove grinding wheel just 5.4% of pump outlet flow rate and 0.5% of spindle energy is needed to reduce the grinding temperature to 200 °C, which means the developed grinding wheel makes cooling high efficient and low energy consuming.

Effective slip for Stokes flow between two grooved walls with an arbitrary phase shift

Energy Technology Data Exchange (ETDEWEB)

Ng, Chiu-On, E-mail: cong@hku.hk [Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road (Hong Kong)

2017-04-15

This work aims to determine how the effective slip length for a wall-bounded flow may depend on, among other geometrical parameters, the phase shift between patterns on the two walls. An analytical model is developed for Stokes flow through a channel bounded by walls patterned with a regular array of rectangular ribs and grooves, where the patterns on the two walls can be misaligned by any phase shift. This study incorporates several previous studies as limiting or special cases. It is shown that the phase shift can have qualitatively different effects on the flow rate and effective slip length, depending on the flow direction. In a narrow channel, increasing the phase shift may mildly decrease the flow rate and effective slip length for flow parallel to the grooves, but can dramatically increase the flow rate and effective slip length for flow transverse to the grooves. It is found that unless the channel height is much larger than the period of the wall pattern, the effect due to wall confinement has to be taken into account on evaluating the effective slip lengths. (paper)

Analysis of focusing error signals by differential astigmatic method under off-center tracking in the land-groove-type optical disk

Science.gov (United States)

Shinoda, Masahisa; Nakatani, Hidehiko

2015-04-01

We theoretically calculate the behavior of the focusing error signal in the land-groove-type optical disk when the objective lens traverses on out of the radius of the optical disk. The differential astigmatic method is employed instead of the conventional astigmatic method for generating the focusing error signals. The signal behaviors are compared and analyzed in terms of the gain difference of the slope sensitivity of the focusing error signals from the land and the groove. In our calculation, the format of digital versatile disc-random access memory (DVD-RAM) is adopted as the land-groove-type optical disk model, and advantageous conditions for suppressing the gain difference are investigated. The calculation method and results described in this paper will be reflected in the next generation land-groove-type optical disks.

The effects of linear accelerations on the maximum heat transfer capacity of micro pipes with triangular grooves

International Nuclear Information System (INIS)

Shokouhmand, H.; Kahrobaian, A.; Tabandeh, N.; Jalilvand, A.

2002-01-01

Micro heat pipes are widely used for the thermal control of spacecraft and their electronic components. In this paper the influence of linear accelerations in micro grooves has been studied. A mathematical model for predicating the minimum meniscus radius and the maximum heat transport in triangular groove under the influence of linear acceleration is presented and method for determining the theoretical minimum meniscus radius is developed. It is shown that both, the direction and the magnitude of the acceleration have a great effect upon heat transfer capability of micro heat pipes. The analysis presented here provides a mechanism where by the groove geometry can be optimized with respect to the length of the heat pipe and direction and magnitude of linear acceleration

Influence of side-groove root radius on the ductile fracture toughness of miniature C(T) specimens

Energy Technology Data Exchange (ETDEWEB)

Lucon, E.; Scibetta, M.

2009-05-15

The use of miniature C(T) specimens, MC(T), for fracture toughness measurements in the upper shelf regime has been investigated at SCK-CEN since 2004, in the framework of the Electrabel/Tractebel SCK-CEN Convention (now General Framework Agreement SUEZ-SCK-CEN). This geometry has been used and validated on both unirradiated (2004-05) and irradiated (2006) materials, mainly reactor pressure vessel (RPV) steels. While side-grooved MC(T) specimens have shown in all conditions a systematically lower tearing resistance and ductile crack initiation toughness as compared to standard-size 1TC(T) samples, the only plain-sided MC(T) specimen tested in 2005 exhibited very high ductile fracture toughness, thus pointing at a strong influence of side-grooving on the upper shelf properties of MC(T) specimens. This study investigates the influence of side-grooving on the initiation toughness and tearing resistance of MC(T) specimens, as a function of the root radius of the side-groove (ranging from 0.1 to 1 mm) and in comparison with plain-sided MC(T) and reference 1TC(T) samples. The material used is the well characterized DIN 22NiMoCr37 RPV steel, which had been used in the European project which generated the famous EURO fracture toughness data set.

Apical groove type and molecular phylogeny suggests reclassification of Cochlodinium geminatum as Polykrikos geminatum.

Science.gov (United States)

Qiu, Dajun; Huang, Liangmin; Liu, Sheng; Zhang, Huan; Lin, Senjie

2013-01-01

Traditionally Cocholodinium and Gymnodinium sensu lato clade are distinguished based on the cingulum turn number, which has been increasingly recognized to be inadequate for Gymnodiniales genus classification. This has been improved by the combination of the apical groove characteristics and molecular phylogeny, which has led to the erection of several new genera (Takayama, Akashiwo, Karenia, and Karlodinium). Taking the apical groove characteristics and molecular phylogeny combined approach, we reexamined the historically taxonomically uncertain species Cochlodinium geminatum that formed massive blooms in Pearl River Estuary, China, in recent years. Samples were collected from a bloom in 2011 for morphological, characteristic pigment, and molecular analyses. We found that the cingulum in this species wraps around the cell body about 1.2 turns on average but can appear under the light microscopy to be >1.5 turns after the cells have been preserved. The shape of its apical groove, however, was stably an open-ended anticlockwise loop of kidney bean shape, similar to that of Polykrikos. Furthermore, the molecular phylogenetic analysis using 18S rRNA-ITS-28S rRNA gene cistron we obtained in this study also consistently placed this species closest to Polykrikos within the Gymnodinium sensu stricto clade and set it far separated from the clade of Cochlodinium. These results suggest that this species should be transferred to Polykrikos as Polykrikos geminatum. Our results reiterate the need to use the combination of apical groove morphology and molecular phylogeny for the classification of species within the genus of Cochlodinium and other Gymnodiniales lineages.

Apical groove type and molecular phylogeny suggests reclassification of Cochlodinium geminatum as Polykrikos geminatum.

Directory of Open Access Journals (Sweden)

Dajun Qiu

Full Text Available Traditionally Cocholodinium and Gymnodinium sensu lato clade are distinguished based on the cingulum turn number, which has been increasingly recognized to be inadequate for Gymnodiniales genus classification. This has been improved by the combination of the apical groove characteristics and molecular phylogeny, which has led to the erection of several new genera (Takayama, Akashiwo, Karenia, and Karlodinium. Taking the apical groove characteristics and molecular phylogeny combined approach, we reexamined the historically taxonomically uncertain species Cochlodinium geminatum that formed massive blooms in Pearl River Estuary, China, in recent years. Samples were collected from a bloom in 2011 for morphological, characteristic pigment, and molecular analyses. We found that the cingulum in this species wraps around the cell body about 1.2 turns on average but can appear under the light microscopy to be >1.5 turns after the cells have been preserved. The shape of its apical groove, however, was stably an open-ended anticlockwise loop of kidney bean shape, similar to that of Polykrikos. Furthermore, the molecular phylogenetic analysis using 18S rRNA-ITS-28S rRNA gene cistron we obtained in this study also consistently placed this species closest to Polykrikos within the Gymnodinium sensu stricto clade and set it far separated from the clade of Cochlodinium. These results suggest that this species should be transferred to Polykrikos as Polykrikos geminatum. Our results reiterate the need to use the combination of apical groove morphology and molecular phylogeny for the classification of species within the genus of Cochlodinium and other Gymnodiniales lineages.

Study of Mastoid Canals and Grooves in North Karnataka Human Skulls

OpenAIRE

Hadimani, Gavishiddappa Andanappa; Bagoji, Ishwar Basavantappa

2013-01-01

Introduction: This study was undertaken to observe the frequency of mastoid canals and grooves in north Karnataka dry human skulls. 100 dry human skulls of unknown age and sex from the department of Anatomy were selected and observed for the present study.

Condensation and Evaporation Transitions in Deep Capillary Grooves

OpenAIRE

Malijevský, A. (Alexandr); Parry, A.O.

2014-01-01

We study the order of capillary condensation and evaporation transitions of a simple fluid adsorbed in a deep capillary groove using a fundamental measure density functional theory (DFT). The walls of the capillary interact with the fluid particles via long-ranged, dispersion, forces while the fluid-fluid interaction is modelled as a truncated Lennard-Jones-like potential. We find that below the wetting temperature $T_w$ condensation is first-order and evaporation is continuous with the metas...

In-vivo study of adhesion and bone growth around implanted laser groove/RGD-functionalized Ti-6Al-4V pins in rabbit femurs

Energy Technology Data Exchange (ETDEWEB)

Chen, J., E-mail: jianboc@gmail.com [Princeton Institute of Science and Technology of Materials and Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544 (United States); Bly, R.A. [Princeton Institute of Science and Technology of Materials and Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544 (United States); Saad, M.M.; AlKhodary, M.A.; El-Backly, R.M. [Tissue Engineering laboratories, Faculty of Dentistry, Alexandria University, Alexandria (Egypt); Cohen, D.J.; Kattamis, N. [Princeton Institute of Science and Technology of Materials and Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544 (United States); Fatta, M.M.; Moore, W.A. [Tissue Engineering laboratories, Faculty of Dentistry, Alexandria University, Alexandria (Egypt); Arnold, C.B. [Princeton Institute of Science and Technology of Materials and Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544 (United States); Marei, M.K. [Tissue Engineering laboratories, Faculty of Dentistry, Alexandria University, Alexandria (Egypt); Soboyejo, W.O. [Princeton Institute of Science and Technology of Materials and Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544 (United States)

2011-07-20

Titanium surfaces were designed, produced, and evaluated for levels of osseointegration into the femurs of rabbits. A total of 36 Ti-6Al-4V pins (15 mm length, 1.64 mm diameter) were prepared into three experimental groups. These were designed to test the effects of osseointegration on laser grooved, RGD coated, and polished control surfaces, as well as combined effects. Circumferential laser grooves were introduced onto pin surfaces (40 {mu}m spacing) using a UV laser ({lambda} = 355 nm). The tripeptide sequence, Arginine-Glycine-Aspartic acid (RGD), was functionalized onto laser grooved surfaces. Of the prepared samples, surface morphology and chemistry were analyzed using scanning electron microscopy (SEM) and Immunoflourescence (IF) spectroscopy, respectively. The experimental pin surfaces were surgically implanted into rabbit femurs. The samples were then harvested and evaluated histologically. Sections of the sample were preserved in a methylmethacralate mold, sliced via a hard microtome, and polished systematically. In the case of the RGD coated and laser grooved surfaces, histological results showed accelerated bone growth into the implant, pull-out tests were also used to compare the adhesion between bone and the titanium pins with/without laser textures and/or RGD coatings. - Research highlights: {yields} Circumferential laser grooves were introduced onto pin surfaces using a UV laser. {yields} The tripeptide sequence, RGD, was functionalized onto laser grooved surfaces. {yields} The experimental pin surfaces were surgically implanted into rabbit femurs. {yields} RGD coated laser groove surfaces accelerated bone growth into the implant. {yields} RGD coated laser grooved surfaces enhanced the adhesion between the bone and implant.

In-vivo study of adhesion and bone growth around implanted laser groove/RGD-functionalized Ti-6Al-4V pins in rabbit femurs

International Nuclear Information System (INIS)

Chen, J.; Bly, R.A.; Saad, M.M.; AlKhodary, M.A.; El-Backly, R.M.; Cohen, D.J.; Kattamis, N.; Fatta, M.M.; Moore, W.A.; Arnold, C.B.; Marei, M.K.; Soboyejo, W.O.

2011-01-01

Titanium surfaces were designed, produced, and evaluated for levels of osseointegration into the femurs of rabbits. A total of 36 Ti-6Al-4V pins (15 mm length, 1.64 mm diameter) were prepared into three experimental groups. These were designed to test the effects of osseointegration on laser grooved, RGD coated, and polished control surfaces, as well as combined effects. Circumferential laser grooves were introduced onto pin surfaces (40 μm spacing) using a UV laser (λ = 355 nm). The tripeptide sequence, Arginine-Glycine-Aspartic acid (RGD), was functionalized onto laser grooved surfaces. Of the prepared samples, surface morphology and chemistry were analyzed using scanning electron microscopy (SEM) and Immunoflourescence (IF) spectroscopy, respectively. The experimental pin surfaces were surgically implanted into rabbit femurs. The samples were then harvested and evaluated histologically. Sections of the sample were preserved in a methylmethacralate mold, sliced via a hard microtome, and polished systematically. In the case of the RGD coated and laser grooved surfaces, histological results showed accelerated bone growth into the implant, pull-out tests were also used to compare the adhesion between bone and the titanium pins with/without laser textures and/or RGD coatings. - Research highlights: → Circumferential laser grooves were introduced onto pin surfaces using a UV laser. → The tripeptide sequence, RGD, was functionalized onto laser grooved surfaces. → The experimental pin surfaces were surgically implanted into rabbit femurs. → RGD coated laser groove surfaces accelerated bone growth into the implant. → RGD coated laser grooved surfaces enhanced the adhesion between the bone and implant.

Steady State Thermo-Hydrodynamic Analysis of Two-Axial groove and Multilobe Hydrodynamic Bearings

Directory of Open Access Journals (Sweden)

C. Bhagat

2014-12-01

Full Text Available Steady state thermo-hydrodynamic analysis of two axial groove and multi lobe oil journal bearings is performed in this paper. To study the steady state thermo-hydrodynamic characteristics Reynolds equation is solved simultaneously along with the energy equation and heat conduction equation in bush and shaft. The effect of groove geometry, cavitation in the fluid film, the recirculation of lubricant, shaft speed has also been taken into account. Film temperature in case of three-lobe bearing is found to be high as compared to other studied bearing configurations. The data obtained from this analysis can be used conveniently in the design of such bearings, which are presented in dimensionless form.

Propagation of Channel Plasmons at the Visible Regime in Aluminum V-Groove Waveguides

DEFF Research Database (Denmark)

Lotan, Oren; Smith, Cameron; Bar-David, Jonathan

2016-01-01

Aluminum plasmonics is emerging as a promising platform in particular for the ultraviolet-blue spectral band. We present the experimental results of propagating channel plasmon-polaritons (CPP) waves in aluminum coated V-shaped waveguides at the short visible wavelength regime. The V-grooves are ......Aluminum plasmonics is emerging as a promising platform in particular for the ultraviolet-blue spectral band. We present the experimental results of propagating channel plasmon-polaritons (CPP) waves in aluminum coated V-shaped waveguides at the short visible wavelength regime. The V......-grooves are fabricated by a process involving UV-photolithography, crystallographic silicon etching, and metal deposition. Polarization measurements of coupling demonstrate a preference to the TM-aligned mode, as predicted in simulations....

Bifurcation analysis of an aerodynamic journal bearing system considering the effect of stationary herringbone grooves

International Nuclear Information System (INIS)

Wang, C.-C.

2007-01-01

This paper investigates the bifurcation and nonlinear behavior of an aerodynamic journal bearing system taking into account the effect of stationary herringbone grooves. A finite difference method based on the successive over relation approach is employed to solve the Reynolds' equation. The analysis reveals a complex dynamical behavior comprising periodic and quasi-periodic responses of the rotor center. The dynamic behavior of the bearing system varies with changes in the bearing number and rotor mass. The results of this study provide a better understanding of the nonlinear dynamics of aerodynamic grooved journal bearing systems

State of the art: Asphalt for airport pavement surfacing

Directory of Open Access Journals (Sweden)

Greg White

2018-01-01

Full Text Available Airport runways and taxiways are commonly comprised of a flexible pavement with an asphalt surface. Marshall-designed asphalt with sawn grooves is the most frequent airport asphalt surface material. However, some airports have adopted alternate asphalt mixtures for improved resistance to shear stress and for increased surface texture, allowing grooving to be avoided. Of the alternate asphalt mixtures, stone mastic asphalt is the most commonly reported. Resistance to shear stress is a critical performance requirement for airport surface asphalt. Shear stress resistance minimises the risk of rutting, shoving and groove closure. However, fracture resistance must not be ignored when developing even more shear resistance asphalt mixtures. Significant distress in airport asphalt surfaces, compliant with the traditional prescriptive specification, has increased interest in a performance-based airport asphalt specification. Commonly reported distresses include groove closure in slow moving aircraft areas and shearing in heavy aircraft braking zones. Development of reliable performance-indicative test methods is expected in the future and will enable warranted performance-based asphalt mixture design for airport surfaces. Keywords: Airport, Pavement, Asphalt, Surface

The suppression effect of a periodic surface with semicircular grooves on the high power microwave long pill-box window multipactor phenomenon

International Nuclear Information System (INIS)

Zhang, Xue; Wang, Yong; Fan, Junjie; Zhong, Yong; Zhang, Rui

2014-01-01

To improve the transmitting power in an S-band klystron, a long pill-box window that has a disk with grooves with a semicircular cross section is theoretically investigated and simulated. A Monte-Carlo algorithm is used to track the secondary electron trajectories and analyze the multipactor scenario in the long pill-box window and on the grooved surface. Extending the height of the long-box window can decrease the normal electric field on the surface of the window disk, but the single surface multipactor still exists. It is confirmed that the window disk with periodic semicircular grooves can explicitly suppress the multipactor and predominantly depresses the local field enhancement and the bottom continuous multipactor. The difference between semicircular and sharp boundary grooves is clarified numerically and analytically

The suppression effect of a periodic surface with semicircular grooves on the high power microwave long pill-box window multipactor phenomenon

Science.gov (United States)

Zhang, Xue; Wang, Yong; Fan, Junjie; Zhong, Yong; Zhang, Rui

2014-09-01

To improve the transmitting power in an S-band klystron, a long pill-box window that has a disk with grooves with a semicircular cross section is theoretically investigated and simulated. A Monte-Carlo algorithm is used to track the secondary electron trajectories and analyze the multipactor scenario in the long pill-box window and on the grooved surface. Extending the height of the long-box window can decrease the normal electric field on the surface of the window disk, but the single surface multipactor still exists. It is confirmed that the window disk with periodic semicircular grooves can explicitly suppress the multipactor and predominantly depresses the local field enhancement and the bottom continuous multipactor. The difference between semicircular and sharp boundary grooves is clarified numerically and analytically.

The suppression effect of a periodic surface with semicircular grooves on the high power microwave long pill-box window multipactor phenomenon

Energy Technology Data Exchange (ETDEWEB)

Zhang, Xue, E-mail: zhangxue.iecas@yahoo.com; Wang, Yong; Fan, Junjie; Zhong, Yong; Zhang, Rui [Institute of Electronics, Chinese Academy of Sciences, Peking, 100190 China (China)

2014-09-15

To improve the transmitting power in an S-band klystron, a long pill-box window that has a disk with grooves with a semicircular cross section is theoretically investigated and simulated. A Monte-Carlo algorithm is used to track the secondary electron trajectories and analyze the multipactor scenario in the long pill-box window and on the grooved surface. Extending the height of the long-box window can decrease the normal electric field on the surface of the window disk, but the single surface multipactor still exists. It is confirmed that the window disk with periodic semicircular grooves can explicitly suppress the multipactor and predominantly depresses the local field enhancement and the bottom continuous multipactor. The difference between semicircular and sharp boundary grooves is clarified numerically and analytically.

Ultrastructure of the harmful unarmored dinoflagellate Cochlodinium polykrikoides (Dinophyceae) with reference to the apical groove and flagellar apparatus

DEFF Research Database (Denmark)

Iwataki, Mitsunori; Hansen, Gert; Moestrup, Øjvind

2010-01-01

The external and internal ultrastructure of the harmful unarmored dinoflagellate Cochlodinium polykrikoides Margalef has been examined with special reference to the apical groove and three-dimensional structure of the flagellar apparatus. The apical groove is U-shaped and connected to the anterior...

[Lymphogranuloma venereum: new serovariant L2b and old "groove sign"].

Science.gov (United States)

de Lavaissière, M; Nougué, J

2013-08-01

An ongoing lymphogranuloma venereum (LGV) outbreak has been reported in several European countries since 2003, related to a new variant L2b. This serovar appears to affect men who have sex with men (MSM), most of them being co-infected with the Human Immunodeficiency Virus (HIV). The secondary stage of LGV may involve lymph nodes and the inguinal form has sometimes been described on each side of the inguinal ligament thus named the "groove sign". We report the case of LGV serovariant L2b acquired by an heterosexual intercourse in an HIV seronegative patient who presented with an inguinal lymph node and a "groove sign". This is an uncommon but suggestive sign of LGV and we suggest that the clinical presentation of L2b LGV might not be so different than other variants and than the 20th century authors' description. Such a new Chlamydia trachomatis variant may circulate in other populations than MSM in Europe and clinical awareness must prevail.

Influence of groove size and reinforcements addition on mechanical properties and microstructure of friction stir welded joints

Science.gov (United States)

Reddy Baridula, Ravinder; Ibrahim, Abdullah Bin; Yahya, Che Ku Mohammad Faizal Bin Che Ku; Kulkarni, Ratnakar; Varma Ramaraju, Ramgopal

2018-03-01

The butt joints fabricated by friction stir welding were found to have more strength than the joints obtained by conventional joining process. The important outcome of this process is the successful fabrication of surface composites with improved properties. Thus in order to further enhance the strength of the dissimilar alloy joints the reinforcements can be deposited in to the aluminium matrix during the process of friction stir welding. In the present study the multi-walled carbon nanotubes were embedded in to the groove by varying the width during joining of dissimilar alloys AA2024 and AA7075. Four widths were selected with constant depth and optimum process parameters were selected to fabricate the sound welded joints. The results show that the mechanical properties of the fabricated butt joints were influenced by the size of the groove, due to variation in the deposition of reinforcement in the stir zone. The microstructural study and identification of the elements of the welded joints show that the reinforcements deposition is influenced by the size of the groove. It has also been observed that the groove with minimum width is more effective than higher width. The mechanical properties are found to be improved due to the pinning of grain boundaries.

Endodontic and periodontal management of a severely affected maxillary lateral incisor having combined mucosal fenestration and palatogingival groove

Directory of Open Access Journals (Sweden)

Sarang Sharma

2015-01-01

Full Text Available Mucosal fenestrations, wherein the tooth root apices are clinically discernible in the oral cavity subsequent to loss of overlying alveolar bone and mucosa, are rare pathologic entities. Palato gingival grooves- anatomic aberrations are also infrequent occurrences that notoriously predispose to periodontal pathologies of varying extent. Both conditions independently are known to popularly affect maxillary lateral incisors. Coexistent fenestration defect and palato gingival groove in the same tooth is extremely rare and undoubtedly is a perfect combination to precipitate severe endodontic-periodontal consequences. In this report, a 34-year-old patient presented to the dental department with complaint of esthetics in relation to exposed root of right maxillary lateral incisor. On closer inspection, a palato gingival groove in addition to fenestration defect was evident on the root surface along with a periodontal pocket of >5 mm. An interdisciplinary treatment was instituted which included endodontic treatment followed by root end resection, osseous bone graft placement and guided tissue regeneration procedures for repair of mucosal fenestration defect. Debridement of the palatal pocket, with saucerization of the groove and restoration with glass ionomer cement were simultaneously employed to correct the palatal defect.

Predicting capacities of runways serving new large aircraft

Directory of Open Access Journals (Sweden)

K. Gopalakrishnan

2008-03-01

Full Text Available This paper presents a simplified approach for predicting the allowable load repetitions of New Large Aircraft (NLA loading for airfield runways based on Non-Destructive Test (NDT data. Full-scale traffic test results from the Federal Aviation Administration’s National Airport Pavement Test Facility (NAPTF were used to develop the NDT-based evaluation methodology. Four flexible test pavement sections with variable (unbound layer thicknesses were trafficked using six-wheel and four-wheel NLA test gears until the test pavements were deemed failed. Non-destructive tests using a Heavy Weight Deflectometer (HWD were conducted prior to the initiation of traffic testing to measure the pavement surface deflections. In the past, pavement surface deflections have been successfully used as an indicator of airport pavement life. In this study, the HWD surface deflections and the derived Deflection Basin Parameters (DBPs were related to functional performance of NAPTF flexible pavements through simple regression analysis. The results demonstrated the usefulness of NDT data for predicting the performance of airport flexible pavements serving the next generation of aircrafts.

Groove Pancreatitis with Biliary and Duodenal Stricture: An Unusual Cause of Obstructive Jaundice

Directory of Open Access Journals (Sweden)

Marta Gravito-Soares

2016-05-01

Discussion: Groove pancreatitis is a benign cause of obstructive jaundice, whose main differential diagnosis is duodenal or pancreatic neoplasia. When this condition causes duodenal or biliary stricture, surgical treatment can be necessary.

Numerical Calculation for Whirling Motion of a Centrifugal Blood Pump with Conical Spiral Groove Bearings

Science.gov (United States)

Shigemaru, Daichi; Tsukamoto, Hiroshi

2010-06-01

Whirling motion of a pump impeller was calculated for the centrifugal blood pump with Conical Spiral Groove Bearings to get a criterion for the instability of impeller whirling motion. The motion of the centrifugal blood pump impeller was calculated based on a spring damping model, and unsteady flow in the pump was computed using the commercial CFD package ANSYS CFX. Also the whirling motion of rotating impeller was measured using two displacement sensors fixed to the blood pump casing. The numerical calculations were done for the blood pump impeller with conical spiral groove bearings, and impeller whirling motion was evaluated.

Genetic Algorithm-Based Optimization for Surface Roughness in Cylindrically Grinding Process Using Helically Grooved Wheels

Science.gov (United States)

Çaydaş, Ulaş; Çelik, Mahmut

The present work is focused on the optimization of process parameters in cylindrical surface grinding of AISI 1050 steel with grooved wheels. Response surface methodology (RSM) and genetic algorithm (GA) techniques were merged to optimize the input variable parameters of grinding. The revolution speed of workpiece, depth of cut and number of grooves on the wheel were changed to explore their experimental effects on the surface roughness of machined bars. The mathematical models were established between the input parameters and response by using RSM. Then, the developed RSM model was used as objective functions on GA to optimize the process parameters.

Olfactory groove meningiomas: approaches and complications.

Science.gov (United States)

Aguiar, Paulo Henrique Pires de; Tahara, Adriana; Almeida, Antonio Nogueira; Simm, Renata; Silva, Arnaldo Neves da; Maldaun, Marcos Vinicius Calfatt; Panagopoulos, Alexandros Theodoros; Zicarelli, Carlos Alexandre; Silva, Pedro Gabriel

2009-09-01

Olfactory groove meningiomas (OGM) account for 4.5% of all intracranial meningiomas. We report 21 patients with OGMs. Tumors were operated on using three surgical approaches: bifrontal (7 patients), fronto-pterional (11 patients) and fronto-orbital (3 patients). Total tumor removal (Simpson Grade 1) was achieved in 13 patients and Simpson II in 8 patients. Perioperative mortality was 4.76%. The average size of the OGM was 4.3+/-1.1cm. The overall recurrence rate was 19%. We preferred to use the pterional approach, which provides quick access to the tumor with less brain exposure. It also allows complete drainage of cisternal cerebrospinal fluid, providing a good level of brain relaxation during surgery. However, for long, thin tumors, hemostasis can be difficult using this approach.

A monofunctional platinum complex coordinated to a rhodium metalloinsertor selectively binds mismatched DNA in the minor groove.

Science.gov (United States)

Weidmann, Alyson G; Barton, Jacqueline K

2015-10-05

We report the synthesis and characterization of a bimetallic complex derived from a new family of potent and selective metalloinsertors containing an unusual Rh-O axial coordination. This complex incorporates a monofunctional platinum center containing only one labile site for coordination to DNA, rather than two, and coordinates DNA nonclassically through adduct formation in the minor groove. This conjugate displays bifunctional, interdependent binding of mismatched DNA via metalloinsertion at a mismatch as well as covalent platinum binding. DNA sequencing experiments revealed that the preferred site of platinum coordination is not the traditional N7-guanine site in the major groove, but rather N3-adenine in the minor groove. The complex also displays enhanced cytotoxicity in mismatch repair-deficient and mismatch repair-proficient human colorectal carcinoma cell lines compared to the chemotherapeutic cisplatin, and it triggers cell death via an apoptotic pathway, rather than the necrotic pathway induced by rhodium metalloinsertors.

Determinig the Shape Coefficient A of Groove on the Pen for the Shaft

Science.gov (United States)

Křístek, Ivo; Havlík, Jiří; Mosler, Václav; Daniš, Igor

2017-12-01

This article focuses on creating a diagram for determining the shape coefficient α for a tongue groove on the shaft. Experimental determination of curve diagrams by comparing diagrams and monograms used using FEM calculations.

Nail findings in patients with psoriatic arthritis: A cross-sectional study with special reference to transverse grooves.

Science.gov (United States)

Zenke, Yukari; Ohara, Yuri; Kobayashi, Daiki; Arai, Satoru; Kishimoto, Mitsumasa; Okada, Masato; Eto, Hikaru

2017-11-01

Patients with psoriatic arthritis (PsA) commonly present with nail manifestations; however, little is known about these manifestations. This study investigated whether nail findings can be used to discriminate between PsA and psoriasis without arthritis. We performed a retrospective analysis of 118 patients with PsA and 974 patients with psoriasis without arthritis who visited St. Luke's International Hospital (Tokyo, Japan) between July 2003 and February 2015. Patients with PsA were classified according to the Classification of Psoriatic Arthritis criteria. Skin lesion severity was assessed by using the Psoriasis Area and Severity Index, and 9 types of nail findings were investigated. The incidence of nail involvement in patients with PsA was 67.6%. Female sex, presence of transverse grooves, onycholysis, and splinter hemorrhages were significantly related to PsA, with transverse grooves demonstrating the strongest association (odds ratio, 5.01; 95% confidence interval, 2.31-10.8; P transverse grooves was strongly related to both distal interphalangeal arthritis and enthesitis. The PsA population was relatively small. Nail findings enabled us to distinguish patients with PsA from those without arthritis. The presence of transverse grooves is significantly associated with PsA and may be associated with distal interphalangeal arthritis and enthesitis. Copyright © 2017 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

Simultaneous minimization of leaf travel distance and tongue-and-groove effect for segmental intensity-modulated radiation therapy

International Nuclear Information System (INIS)

Dai Jianrong; Que, William

2004-01-01

This paper introduces a method to simultaneously minimize the leaf travel distance and the tongue-and-groove effect for IMRT leaf sequences to be delivered in segmental mode. The basic idea is to add a large enough number of openings through cutting or splitting existing openings for those leaf pairs with openings fewer than the number of segments so that all leaf pairs have the same number of openings. The cutting positions are optimally determined with a simulated annealing technique called adaptive simulated annealing. The optimization goal is set to minimize the weighted summation of the leaf travel distance and tongue-and-groove effect. Its performance was evaluated with 19 beams from three clinical cases; one brain, one head-and-neck and one prostate case. The results show that it can reduce the leaf travel distance and (or) tongue-and-groove effect; the reduction of the leaf travel distance reaches its maximum of about 50% when minimized alone; the reduction of the tongue-and-groove reaches its maximum of about 70% when minimized alone. The maximum reduction in the leaf travel distance translates to a 1 to 2 min reduction in treatment delivery time per fraction, depending on leaf speed. If the method is implemented clinically, it could result in significant savings in treatment delivery time, and also result in significant reduction in the wear-and-tear of MLC mechanics

Olfactory groove meningiomas.

Science.gov (United States)

Hentschel, Stephen J; DeMonte, Franco

2003-06-15

Olfactory groove meningiomas (OGMs) arise over the cribriform plate and may reach very large sizes prior to presentation. They can be differentiated from tuberculum sellae meningiomas because OGMs arise more anterior in the skull base and displace the optic nerve and chiasm inferiorly rather than superiorly. The authors searched the neurosurgery database at the M. D. Anderson Cancer Center for cases of OGM treated between 1993 and 2003. The records of these patients were then reviewed retrospectively for details regarding clinical presentation, imaging findings, surgical results and complications, and follow-up status. Thirteen patients, (12 women and one man, mean age 56 years) harbored OGMs (mean size 5.7 cm). All patients underwent bifrontal craniotomies and biorbital osteotomies. There were 11 complete resections (including the hyperostotic bone and dura of the cribriform plate and any extension into the ethmoid sinuses) and two subtotal resections with minimal residual tumor left in patients with recurrent lesions. No complication directly due to the surgery occurred in any patient. There were no recurrences in a mean follow-up period of 2 years (range 0-5 years). With current microsurgical techniques, the results of OGM resection are excellent, with a high rate of total resection and a low incidence of complications. All hyperostotic bone should be removed with the dura of the anterior skull base to minimize the risk of recurrence.

Treatment of an intrabony osseous lesion associated with a palatoradicular groove

Directory of Open Access Journals (Sweden)

A Suchetha

2012-01-01

Full Text Available Various root developmental anomalies like palatoradicular groove (PRG have been associated with worsening of periodontal condition. The aim of the present case report is to describe the regenerative surgical treatment of periodontal and osseous lesion associated with the subgingival extension of PRG. A 23-year-old female patient reported with pain in upper incisor teeth region. On clinical and radiological examination, a deep endosseous defect was found distal to maxillary right lateral incisor that was etiologically associated with the presence of a PRG. Treatment procedures consisted of: Regenerative periodontal therapy using Guided tissue regeneration (GTR and hydroxyapatite (HA bone graft and 2 flattening of the radicular portion of the palatal groove. The clinical examination at 1 year revealed shallow residual probing depth (3 mm and no increase in gingival recession. The radiographic examination showed reduction in the radiolucency suggesting bone fill. A PRG may serve as a pathway for the development of a periodontal osseous defect. The combination of GTR and HA may be clinically and radiographically efficacious in the treatment of such a defect.

The "sign of groove", a new cutaneous sign of internal malignancy

Directory of Open Access Journals (Sweden)

Nair Pradeep

2007-01-01

Full Text Available A 36-year-old young male with multiple heterosexual contacts presented with bilateral inguinal bubo and the classical "sign of groove". A diagnosis of lymphogranuloma venereum (LGV was made and a three-week course of doxycycline was given. Lack of response prompted us to investigate further. A biopsy of the bubo was consistent with non-Hodgkin′s lymphoma (NHL. Immunohistochemistry of the lymph node done at the Regional Cancer Center (RCC, Trivandrum, confirmed the diagnosis as NHL of diffuse large B-cell type. The second patient, a 32-year-old male with two unprotected heterosexual contacts presented with a left-sided inguinal bubo of six weeks duration. An empirical course of doxycycline was given even though investigations did not reveal any STI. Lack of response prompted us to do a lymph node biopsy, which was consistent with NHL, which later with immunohistochemistry was confirmed as NHL, diffuse large cell type. We are reporting here that the "sign of groove" is not specific for LGV as thought earlier, but can occur in NHL also.

Aircraft Accident Report. Runway Overrun During Landing American Airlines Flight 1420 McDonnell Douglas MD-82, N215AA Little Rock, Arkansas

National Research Council Canada - National Science Library

1999-01-01

This report explains the accident involving American Airlines flight 1420, a McDonnell Douglas MD-82, which crashed after it overran the end of runway 4R during landing at Little Rock National Airport...

Microjetting from grooved surfaces in metallic samples subjected to laser driven shocks

Science.gov (United States)

de Rességuier, T.; Lescoute, E.; Sollier, A.; Prudhomme, G.; Mercier, P.

2014-01-01

When a shock wave propagating in a solid sample reflects from a free surface, geometrical effects predominantly governed by the roughness and defects of that surface may lead to the ejection of tiny jets that may breakup into high velocity, approximately micrometer-size fragments. This process referred to as microjetting is a major safety issue for engineering applications such as pyrotechnics or armour design. Thus, it has been widely studied both experimentally, under explosive and impact loading, and theoretically. In this paper, microjetting is investigated in the specific loading conditions associated to laser shocks: very short duration of pressure application, very high strain rates, small spatial scales. Material ejection from triangular grooves in the free surface of various metallic samples is studied by combining transverse optical shadowgraphy and time-resolved velocity measurements. The influences of the main parameters (groove angle, shock pressure, nature of the metal) on jet formation and ejection velocity are quantified, and the results are compared to theoretical estimates.

Microjetting from grooved surfaces in metallic samples subjected to laser driven shocks

International Nuclear Information System (INIS)

Rességuier, T. de; Lescoute, E.; Sollier, A.; Prudhomme, G.; Mercier, P.

2014-01-01

When a shock wave propagating in a solid sample reflects from a free surface, geometrical effects predominantly governed by the roughness and defects of that surface may lead to the ejection of tiny jets that may breakup into high velocity, approximately micrometer-size fragments. This process referred to as microjetting is a major safety issue for engineering applications such as pyrotechnics or armour design. Thus, it has been widely studied both experimentally, under explosive and impact loading, and theoretically. In this paper, microjetting is investigated in the specific loading conditions associated to laser shocks: very short duration of pressure application, very high strain rates, small spatial scales. Material ejection from triangular grooves in the free surface of various metallic samples is studied by combining transverse optical shadowgraphy and time-resolved velocity measurements. The influences of the main parameters (groove angle, shock pressure, nature of the metal) on jet formation and ejection velocity are quantified, and the results are compared to theoretical estimates

Microjetting from grooved surfaces in metallic samples subjected to laser driven shocks

Energy Technology Data Exchange (ETDEWEB)

Rességuier, T. de, E-mail: resseguier@ensma.fr [Institut PPRIME, UPR 3346, CNRS, ENSMA, Université de Poitiers, 1 ave. Clément Ader, 86961 Futuroscope Cedex (France); Lescoute, E.; Sollier, A.; Prudhomme, G.; Mercier, P. [CEA, DAM, DIF, 91297 Arpajon (France)

2014-01-28

When a shock wave propagating in a solid sample reflects from a free surface, geometrical effects predominantly governed by the roughness and defects of that surface may lead to the ejection of tiny jets that may breakup into high velocity, approximately micrometer-size fragments. This process referred to as microjetting is a major safety issue for engineering applications such as pyrotechnics or armour design. Thus, it has been widely studied both experimentally, under explosive and impact loading, and theoretically. In this paper, microjetting is investigated in the specific loading conditions associated to laser shocks: very short duration of pressure application, very high strain rates, small spatial scales. Material ejection from triangular grooves in the free surface of various metallic samples is studied by combining transverse optical shadowgraphy and time-resolved velocity measurements. The influences of the main parameters (groove angle, shock pressure, nature of the metal) on jet formation and ejection velocity are quantified, and the results are compared to theoretical estimates.

Utilization of the bicipital groove axis for confirming alignment of the humerus with transepicondylar and ulnar shaft axes during intramedullary nailing.

Science.gov (United States)

Meriç, Gökhan; Zeybek, Gülşah; Kıray, Amaç; Atik, Aziz; Budeyri, Aydın; Koşay, Can

2015-01-01

Intramedullary nailing is the preferred surgical treatment of humerus shaft fractures. The purpose of this study was to investigate the relationship between the bicipital groove and specific anatomical landmarks in achieving correct alignment of the humerus during intramedullary nailing, and to describe these anatomical landmarks. Thirty (15 right; 15 left) total upper cadaver extremities were used in this study. After the anatomical landmarks were identified and marked, humeral head axis, transepicondylar axis, ulnar shaft axis, bicipital groove axis, and angular measurements of these were obtained. The mean angle between the bicipital groove axis and transepicondylar axis was 48.17°±12.35º (range: 20.10º to 74.6º). The mean angle between the bicipital groove axis and ulna diaphysis axis was 41.82º±11.56 º (range: 17.91º to 68.27º). The mean angle between the humeral head axis and bicipital groove axis was 20.53°±3.90º (range: 11.85º to 31.81º). The mean retroversion angle between the humeral head axis and transepicondylar axis was 27.52±11.37º (range: 4.26º to 49.36º). The mean angle between the humeral head axis and ulna diaphysis axis was 61.73º±12.08º (range: 33.97º to 86.37º). The mean torsion angle was 62.58º±11.28 º (range: 40.74º to 85.74º). Measurement and utilization of the relationship between the bicipital groove, ulna diaphysis and transepicondylar axes may be used for restoring humeral rotation.

Comparison study on flexible pavement design using FAA (Federal Aviation Administration) and LCN (Load Classification Number) code in Ahmad Yani international airport’s runway

Science.gov (United States)

Santoso, S. E.; Sulistiono, D.; Mawardi, A. F.

2017-11-01

FAA code for airport design has been broadly used by Indonesian Ministry of Aviation since decades ago. However, there is not much comprehensive study about its relevance and efficiency towards current situation in Indonesia. Therefore, a further comparison study on flexible pavement design for airport runway using comparable method has become essential. The main focus of this study is to compare which method between FAA and LCN that offer the most efficient and effective way in runway pavement planning. The comparative methods in this study mainly use the variety of variable approach. FAA code for instance, will use the approach on the aircraft’s maximum take-off weight and annual departure. Whilst LCN code use the variable of equivalent single wheel load and tire pressure. Based on the variables mentioned above, a further classification and rated method will be used to determine which code is best implemented. According to the analysis, it is clear that FAA method is the most effective way to plan runway design in Indonesia with consecutively total pavement thickness of 127cm and LCN method total pavement thickness of 70cm. Although, FAA total pavement is thicker that LCN its relevance towards sustainable and pristine condition in the future has become an essential aspect to consider in design and planning.

USAGE OF FILTERS FROM FIBROUS MATERIALS IN AMELIORATIVE AND HYDRO-TECHNICAL CONSTRUCTION

Directory of Open Access Journals (Sweden)

V. T. Klimkov

2016-01-01

Full Text Available Construction of first drainage tubular systems has been facing such problem as their protection against silting-up by soil particles penetrating through input openings. Searches and investigations have led to usage of various fibrous materials which are playing the role of filters. At the beginning glass-fibre mats have been widely applied for this purpose. However, the mats possessing good filtration properties have had a number of fundamental disadvantages. Works executed at the Institute of Mechanics of Metal Polymeric Systems (Gomel, Republic of Belarus have played a big role in usage of plastic materials. A new technology has been developed with the purpose to obtain thermally-bonded fibres from thermoplastic material. The fibres have been called as polyethylene mats. Investigation of their properties has been carried out under load and it has revealed that their lateral and longitudinal permeability becomes equal at specified pressures, in other words the material takes an isotropic state. The considered interactions of filtrating material and skeleton frame have shown that the main water filtration occurs directly above perforation holes while the material above blind frame sections does not participate in the process. Due to this a new design of the filtrating element has been developed and it can be used in water intake systems for surface and underground water. The filtrating element consists of the skeleton frame with openings and a filtration covering which is installed on the frame. Water-feeding groove cavities are located on the skeleton frame and they are dispersing from perforation holes in the form of beams. These grooves can have side branches of the second, third and other orders. As beam-like arrangement of grooves creates the shortest flow paths for filtrated water from periphery to frame holes and area of groove cross section exceeds the area of poral holes in water in-take covering by a factor of hundreds, it is possible

Saying Hello World with GROOVE - A Solution to the TTC 2011 Instructive Case

NARCIS (Netherlands)

Ghamarian, A.H.; de Mol, M.J.; Rensink, Arend; Zambon, Eduardo; van Gorp, Pieter; Mazanek, Steffen; Rose, Louis

2011-01-01

This report presents a solution to the Hello World case study using GROOVE. We provide and explain the grammar that we used to solve the case study. Every requested question of the case study was solved by a single rule application.

Narrow groove gas metal-arc welding of aluminum

International Nuclear Information System (INIS)

Armstrong, R.E.

1975-01-01

The Gas Metal-Arc (GMA) welding process is explained and the equipment used described with an analysis of power supply function and the action of the arc, followed by discussion of general applications and problems. GMA braze welding of beryllium is then described, as is the development of a special high purity filler wire and a narrow deep groove joint design for improved weld strength in beryllium. This joint design and the special wire are applied in making high strength welds in high strength aluminum for special applications. High speed motion pictures of the welding operation are shown to illustrate the talk. (auth)

A study on the performance of condensation heat transfer for various working fluid of two-phase closed thermosyphons with various helical grooves

International Nuclear Information System (INIS)

Han, Kyu Il; Cho, Dong Hyun

2005-01-01

This study concerns the performance of condensing heat transfer in two-phase closed thermosyphons with various helical grooves. Distilled water, methanol, ethanol have been used as the working fluid. In the present work, a copper tube of the length of 1200mm and 14.28mm of inside diameter is used as the container of the thermosyphon. Each of the evaporator and the condenser section has a length of 550mm, while the remaining part of the thermosyphon tube is adiabatic section. A experimental study was carried out for analyzing the performances of having 50, 60, 70, 80, 90 helical grooves. A plain thermosyphon having the same inner and outer diameter as the grooved thermosyphons is also tested for the comparison. The type of working fluid and the numbers of grooves of the thermosyphons with various helical grooves have been used as the experimental parameters. The experimental results have been assessed and compared with existing theories. The results show that the type of working fluids are very important factors for the operation of thermosyphons. And the maximum enhancement (i.e. the ratio of the heat transfer coefficients the helical thermosyphons to plain thermosyphons) is 1.5∼2 for condensation

Standardized performance tests of collectors of solar thermal energy: Prototype moderately concentrating grooved collectors

Science.gov (United States)

1976-01-01

Prototypes of moderately concentrating grooved collectors were tested with a solar simulator for varying inlet temperature, flux level, and incident angle. Collector performance is correlated in terms of inlet temperature and flux level.

Ledges and grooves at γ/γ′ interfaces of single crystal superalloys

Czech Academy of Sciences Publication Activity Database

Parsa, A. B.; Wollgramm, P.; Buck, H.; Kostka, A.; Somsen, C.; Dlouhý, Antonín; Eggeler, G.

2015-01-01

Roč. 90, MAY (2015), s. 105-117 ISSN 1359-6454 R&D Projects: GA ČR(CZ) GA14-22834S Institutional support: RVO:68081723 Keywords : Ni-base single crystal superalloys * γ/γ′ interfaces * Interface dislocations * Rafting * Grooves Subject RIV: JG - Metallurgy Impact factor: 5.058, year: 2015

Biomimetic "Cactus Spine" with Hierarchical Groove Structure for Efficient Fog Collection.

Science.gov (United States)

Bai, Fan; Wu, Juntao; Gong, Guangming; Guo, Lin

2015-07-01

A biomimetic "cactus spine" with hierarchical groove structure is designed and fabricated using simple electrospinning. This novel artificial cactus spine possesses excellent fog collection and water transportation ability. A model cactus equipped with artificial spines also shows a great water storage capacity. The results can be helpful in the development of water collectors and may make a contribution to the world water crisis.

The Origin of Nanoscopic Grooving on Vesicle Walls in Submarine Basaltic Glass: Implications for Nanotechnology

Directory of Open Access Journals (Sweden)

Jason E. French

2009-01-01

Full Text Available Dendritic networks of nanoscopic grooves measuring 50–75 nm wide by <50 nm deep occur on the walls of vesicles in the glassy margins of mid-ocean ridge pillow basalts worldwide. Until now, their exact origin and significance have remained unclear. Here we document examples of such grooved patterns on vesicle walls in rocks from beneath the North Atlantic Ocean, and give a fluid mechanical explanation for how they formed. According to this model, individual nanogrooves represent frozen viscous fingers of magmatic fluid that were injected into a thin spheroidal shell of hot glass surrounding each vesicle. The driving mechanism for this process is provided by previous numerical predictions of tangential tensile stress around some vesicles in glassy rocks upon cooling through the glass transition. The self-assembling nature of the dendritic nanogrooves, their small size, and overall complexity in form, are interesting from the standpoint of exploring new applications in the field of nanotechnology. Replicating such structures in the laboratory would compete with state-of-the-art nanolithography techniques, both in terms of pattern complexity and size, which would be useful in the fabrication of a variety of grooved nanodevices. Dendritic nanogrooving in SiO2 glass might be employed in the manufacturing of integrated circuits.

Nanoscale Plasmonic V-Groove Waveguides for the Interrogation of Single Fluorescent Bacterial Cells

DEFF Research Database (Denmark)

Lotan, Oren; Bar-David, Jonathan; Smith, Cameron

2017-01-01

We experimentally demonstrate the interrogation of an individual Escherichia coli cell using a nanoscale plasmonic V-groove waveguide. Several different configurations were studied. The first involved the excitation of the cell in a liquid environment because it flows on top of the waveguide...

An investigation of the initial attachment and orientation of osteoblast-like cells on laser grooved Ti-6Al-4V surfaces

Energy Technology Data Exchange (ETDEWEB)

Chen, J., E-mail: jianboc@Princeton.EDU [Princeton Institute of Science and Technology of Materials, Princeton University, Princeton, NJ 08544 (United States); Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544 (United States); Ulerich, J.P. [Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544 (United States); Abelev, E. [Department of Chemistry, Princeton University, Princeton, NJ 08544 (United States); Fasasi, A. [Princeton Institute of Science and Technology of Materials, Princeton University, Princeton, NJ 08544 (United States); Center for Energy Research, Obafemi Awolowo University, Ile-Ife (Nigeria); Arnold, C.B.; Soboyejo, W.O. [Princeton Institute of Science and Technology of Materials, Princeton University, Princeton, NJ 08544 (United States); Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544 (United States)

2009-05-05

This paper presents the results of an experimental study of the initial cell spreading and adhesion on longitudinally- and transversally-oriented micro-grooves produced by the laser irradiation of laser grooved Ti-6Al-4V surfaces. The initial spreading and orientations of human osteosarcoma (HOS) cells were observed and quantified after 15-min, 1-hour, 4-hour and 24-hour cell culture periods. Immuno-fluorescence staining of adhesion proteins (actin and vinculin) was then used to study the spreading and adhesion of HOS cells in 1 hour and 4 hour culture experiments. The initial cell adhesion was also quantified using enzymatic detachment tests. The results showed that cell spreading and adhesion were enhanced by longitudinally- and transversally-oriented micro-grooves. The effects, which increase with time, were not remarkable after 1 hour, but obvious after 4 hours. Contact guidance was found to promote cell adhesion due to the increase in interactions between the focal adhesions and the patterned extra-cellular matrix (ECM) proteins on the laser micro-grooved surfaces.

An investigation of the initial attachment and orientation of osteoblast-like cells on laser grooved Ti-6Al-4V surfaces

International Nuclear Information System (INIS)

Chen, J.; Ulerich, J.P.; Abelev, E.; Fasasi, A.; Arnold, C.B.; Soboyejo, W.O.

2009-01-01

This paper presents the results of an experimental study of the initial cell spreading and adhesion on longitudinally- and transversally-oriented micro-grooves produced by the laser irradiation of laser grooved Ti-6Al-4V surfaces. The initial spreading and orientations of human osteosarcoma (HOS) cells were observed and quantified after 15-min, 1-hour, 4-hour and 24-hour cell culture periods. Immuno-fluorescence staining of adhesion proteins (actin and vinculin) was then used to study the spreading and adhesion of HOS cells in 1 hour and 4 hour culture experiments. The initial cell adhesion was also quantified using enzymatic detachment tests. The results showed that cell spreading and adhesion were enhanced by longitudinally- and transversally-oriented micro-grooves. The effects, which increase with time, were not remarkable after 1 hour, but obvious after 4 hours. Contact guidance was found to promote cell adhesion due to the increase in interactions between the focal adhesions and the patterned extra-cellular matrix (ECM) proteins on the laser micro-grooved surfaces.

Effectiveness of noise barriers installed adjacent to transverse grooved concrete pavement : executive summary report.

Science.gov (United States)

2009-10-16

In recent years the Ohio Department of Transportation (ODOT) has reconstructed a number of roadways where asphalt pavements were replaced with concrete pavements which were finished with a random transverse grooved surface texture (ODOT specification...

Photolithography of thick photoresist coating in anisotropically etched V-grooves for electrically controlled liquid crystal photonic bandgap fiber devices

DEFF Research Database (Denmark)

Wei, Lei; Khomtchenko, Elena; Alkeskjold, Thomas Tanggaard

2009-01-01

Thick photoresist coating for electrode patterning in anisotropically etched v-grooves is investigated. The photoresist coverage is compared with and without soft baking. Two-step exposure is applied for a complete exposure and minimizing the resolution loss.......Thick photoresist coating for electrode patterning in anisotropically etched v-grooves is investigated. The photoresist coverage is compared with and without soft baking. Two-step exposure is applied for a complete exposure and minimizing the resolution loss....

W-CDMA Uplink Capacity and Interference Statistics of a LongGroove-Shaped Road Microcells Using A Hybrid Propagation Model

Directory of Open Access Journals (Sweden)

L. de Haro-Ariet

2003-09-01

Full Text Available The uplink capacity and the interference statistics of the sectorsof a long groove-shaped road W-CDMA microcell are studied. A model of 9microcells in a groove-shaped road is used to analyze the uplink. Ahybrid model for the propagation is used in the analysis. The capacityand the interference statistics of the cell are studied for differentsector ranges, different specific attenuation factors, differentantenna side lobe levels and different bend losses.

Flight trajectory of a rotating golf ball with grooves

Science.gov (United States)

Baek, Moonheum; Kim, Jooha; Choi, Haecheon

2014-11-01

Dimples are known to reduce drag on a sphere by the amount of 50% as compared to a smooth surface. Despite the advantage of reducing drag, dimples deteriorate the putting accuracy owing to their sharp edges. To minimize this putting error but maintain the same flight distance, we have devised a grooved golf ball (called G ball hereafter) for several years. In this study, we modify the shape and pattern of grooves, and investigate the flow characteristics of the G ball by performing wind-tunnel experiments at the Reynolds numbers of 0 . 5 ×105 - 2 . 5 ×105 and the spin ratios (ratio of surface velocity to the free-stream velocity) of 0 - 0.6 that include the real golf-ball velocity and rotational speed. We measure the drag and lift forces on the rotating G ball and compare them with those of a smooth ball and two well-known dimpled balls. The lift-to-drag ratio of the G ball is much higher than that of a smooth ball and is in between those of the two dimpled balls. The trajectories of flying golf balls are computed. The flight distance of G ball is almost the same as that of one dimpled ball but slightly shorter than that of the other dimpled ball. The fluid-dynamic aspects of these differences will be discussed at the talk. Supported by 2011-0028032, 2014M3C1B1033980.

Nutrient groove of the ilium, a subtle but important forensic radiographic marker in the identification of victims of severe trauma

International Nuclear Information System (INIS)

Moser, R.P. Jr.; Uniformed Services Univ. of the Health Sciences, Bethesda, MD; Wagner, G.N.

1990-01-01

A variety of skeletal characteristics pertaining to the bony pelvis have, over the years, been of assistance as forensic markers, but the importance of the nutrient groove of the ilium has not been appreciated. During aircraft accident investigations we compared premortem anteroposterior abdominal radiographs with postmortem specimen radiographs of the ilium, with particular attention directed to the nutrient groove of the ilium. This marker can assume several configurations (i.e., parallel, V-shaped and Y-shaped) and is situated a few centimeters lateral to the sacroiliac joint. Left/right asymmetry, or absence of the nutrient grove on one side of the pelvis are possible variants within an individual. The purpose of this report is to emphasize the previously unrecognized importance of the nutrient groove of the ilium as a useful forensic radiographic marker. (orig.)

Analysis of behavior of focusing error signals generated by astigmatic method when a focused spot moves beyond the radius of a land-groove-type optical disk

Science.gov (United States)

Shinoda, Masahisa; Nakatani, Hidehiko; Nakai, Kenya; Ohmaki, Masayuki

2015-09-01

We theoretically calculate behaviors of focusing error signals generated by an astigmatic method in a land-groove-type optical disk. The focusing error signal from the land does not coincide with that from the groove. This behavior is enhanced when a focused spot of an optical pickup moves beyond the radius of the optical disk. A gain difference between the slope sensitivities of focusing error signals from the land and the groove is an important factor with respect to stable focusing servo control. In our calculation, the format of digital versatile disc-random access memory (DVD-RAM) is adopted as the land-groove-type optical disk model, and the dependences of the gain difference on various factors are investigated. The gain difference strongly depends on the optical intensity distribution of the laser beam in the optical pickup. The calculation method and results in this paper will be reflected in newly developed land-groove-type optical disks.

Configurational entropy change of netropsin and distamycin upon DNA minor-groove binding.

Science.gov (United States)

Dolenc, Jozica; Baron, Riccardo; Oostenbrink, Chris; Koller, Joze; van Gunsteren, Wilfred F

2006-08-15

Binding of a small molecule to a macromolecular target reduces its conformational freedom, resulting in a negative entropy change that opposes the binding. The goal of this study is to estimate the configurational entropy change of two minor-groove-binding ligands, netropsin and distamycin, upon binding to the DNA duplex d(CGCGAAAAACGCG).d(CGCGTTTTTCGCG). Configurational entropy upper bounds based on 10-ns molecular dynamics simulations of netropsin and distamycin in solution and in complex with DNA in solution were estimated using the covariance matrix of atom-positional fluctuations. The results suggest that netropsin and distamycin lose a significant amount of configurational entropy upon binding to the DNA minor groove. The estimated changes in configurational entropy for netropsin and distamycin are -127 J K(-1) mol(-1) and -104 J K(-1) mol(-1), respectively. Estimates of the configurational entropy contributions of parts of the ligands are presented, showing that the loss of configurational entropy is comparatively more pronounced for the flexible tails than for the relatively rigid central body.

Saying Hello World with GROOVE - A Solution to the TTC 2011 Instructive Case

Directory of Open Access Journals (Sweden)

Amir Hossein Ghamarian

2011-11-01

Full Text Available This report presents a solution to the Hello World case study of TTC 2011 using GROOVE. We provide and explain the grammar that we used to solve the case study. Every requested question of the case study was solved by a single rule application.

Numerical Analysis of Rotating Pumping Flows in Inter-Coil Rotor Cavities and Short Cooling Grooves of a Generator

Directory of Open Access Journals (Sweden)

Wei Tong

2001-01-01

Full Text Available An important characteristic of wall rotating-driven flows is the tendency of fluid with high angular momentum to be flung radially outward. For a generator, the rotor rotating-driven flow, usually referred to as the rotating pumping flow, plays an important role in rotor winding cooling. In this study, three-dimensional numerical analyzes are presented for turbulent pumping flow in the inter-coil rotor cavity and short cooling grooves of a generator. Calculations of the flow field and the mass flux distribution through the grooves were carried out in a sequence of four related cases Under an isothermal condition: (a pumping flow, which is the self-generated flow resulted from the rotor pumping action; (b mixing flow, which is the combination of the ventilating flow and pumping flow, under a constant density condition; (c mixing flow, with density modeled by the ideal gas law; and (d mixing flow, with different pressure differentials applied on the system. The comparisons of the results from these cases can provide useful information regarding the impacts of the ventilating flow, gas density, and system pressure differential on the mass flux distribution in the short cooling grooves. Results show that the pumping effect is strong enough to generate the cooling flow for rotor winding cooling. Therefore, for small- or mid-size generators ventilation fans may be eliminated. It also suggests that increasing the chimney dimension can improve the distribution uniformity of mass flux through the cooling grooves.

Structural and mechanical behaviour of severe plastically deformed high purity aluminium sheets processed by constrained groove pressing technique

International Nuclear Information System (INIS)

Satheesh Kumar, S.S.; Raghu, T.

2014-01-01

Highlights: • High purity aluminium sheets constrained groove pressed up to plastic strain of 5.8. • Microstructural evolution studied by TEM and X-ray diffraction profile analysis. • Ultrafine grained structure with grain size ∼900 nm achieved in sheets. • Yield strength increased by 5.3 times and tensile strength doubled after first pass. • Enhanced deformation homogeneity seen with increased accumulated plastic strain. - Abstract: High purity aluminium sheets (∼99.9%) are subjected to intense plastic straining by constrained groove pressing method successfully up to 5 passes thereby imparting an effective plastic strain of 5.8. Transmission electron microscopy studies of constrained groove pressed sheets divulged significant grain refinement and the average grain sizes obtained after five pass is estimated to be ∼0.9 μm. In addition to that, microstructural evolution of constrained groove pressed sheets is characterized by X-ray diffraction peak profile analysis employing Williamson–Hall method and the results obtained fairly concur with electron microscopy findings. The tensile behaviour evolution with increased straining indicates substantial improvement of yield strength by ∼5.3 times from 17 MPa to 90 MPa during first pass corroborated to grain refinement observed. Marginal increase in strengths is noticed during second pass followed by minor drop in strengths attributed to predominance of dislocation recovery is noticed in subsequent passes. Quantitative assessment of degree of deformation homogeneity using microhardness profiles reveal relatively better strain homogeneity at higher number of passes

Enhancement of fluorescence quenching and exciplex formation in DNA major groove by double incorporation of modified fluorescent deoxyuridines.

Science.gov (United States)

Tanaka, Makiko; Oguma, Kazuhiro; Saito, Yoshio; Saito, Isao

2012-06-15

5-(1-Naphthalenylethynyl)-2'-deoxyuridine ((N)U) and 5-[(4-cyano-1-naphthalenyl)ethynyl]-2'-deoxyuridine ((CN)U) were synthesized and incorporated into oligodeoxynucleotides. Fluorescence emissions of modified duplexes containing double (N)U were efficiently quenched depending upon the sequence pattern of the naphthalenes in DNA major groove, as compared to the duplex possessing single (N)U. When one of the naphthalene moieties has a cyano substituent, the exciplex emission from the chromophores in DNA major groove was observed at longer wavelength. Copyright © 2012 Elsevier Ltd. All rights reserved.

Generalized Stability Analysis of Capillary Flow in Slender V-Grooves

Science.gov (United States)

White, Nicholas; Troian, Sandra

2017-11-01

Spontaneous capillary flow, an especially rapid process in slender open microchannels resembling V-grooves, is of significant importance to many applications requiring passive robust flow control. Many types of biomedical devices for point-of-care use in developing countries are being designed around this principle. Important fundamental work by Romero and Yost (1996) and Weislogel (1996) elucidated the behavior of Newtonian films in slender V-grooves driven to flow by the streamwise change in capillary pressure due to the change in radius of curvature of the circular arc describing the interface of wetting or non-wetting fluids. Self-similar solutions describing Washburn type dynamics were found but other solutions are possible. Here we extend the Romero and Yost model to include a variety of inlet and outlet boundary conditions and examine the transient growth and generalized stability of perturbations to steady state and self-similar flows. Although most cases examined for wetting fluids exhibit robust stability against small perturbations, some exceptions reveal unstable flow. In total, these results support decades of experimental work which has found this method of flow control to be especially reliable, robust and self-healing. The authors gratefully acknowledge financial support from the 2016 NASA/Jet Propulsion Laboratory President's and Director's Fund as well as a 2017 NASA Space Technology Research Fellowship.

Two 1 : 1 binding modes for distamycin in the minor groove of d(GGCCAATTGG)

Czech Academy of Sciences Publication Activity Database

Uytterhoeven, K.; Šponer, Jiří; Van Meervelt, L.

2002-01-01

Roč. 269, č. 12 (2002), s. 2868-2877 ISSN 0014-2956 R&D Projects: GA MŠk LN00A016 Keywords : distamycin * drug-DNA complex * minor groove binder Subject RIV: BO - Biophysics Impact factor: 2.999, year: 2002

Numerical Simulation and Experimental Study on the Gas-Solid Coupling of the Aerostatic Thrust Bearing with Elastic Equalizing Pressure Groove

Directory of Open Access Journals (Sweden)

Zhao Xiao-long

2017-01-01

Full Text Available Aiming at the problem of low stiffness of aerostatic bearing, according to the principle of gas-solid coupling, this paper designs a kind of aerostatic thrust bearing with elastic equalizing pressure groove (EEPG and investigates the effect of elastic equalizing pressure groove (EEPG on the stiffness of aerostatic bearing. According to the physical model of the bearing, one deduces the deformation control equation of the elastic equalizing pressure groove and the control equation of gas lubrication, using finite difference method to derive the control equations and coupling calculation. The bearing capacity and stiffness of aerostatic bearing with EEPG in different gas film clearance are obtained. The calculation results show that the stiffness increased by 59%. The results of numerical calculation and experimental results have good consistency, proving the gas-solid coupling method can improve the bearing stiffness.

Electrophoresis in ice surface grooves for probing protein affinity to a specific plane of ice crystal.

Science.gov (United States)

Inagawa, Arinori; Okada, Yusuke; Okada, Tetsuo

2018-06-01

Channel-like grooves are formed on the surface of frozen aqueous sucrose. They are filled with a freeze concentrated solution (FCS) and act as an efficient size-tunable separation field for micro and nanoparticles. The width of the channel can be easily varied by changing the temperature. Because the channel width decreases with decreasing temperature, particles become immobilized due to physical interference from the ice wall when the temperature reaches a threshold point specific to the particle size. Surface modification of particles can add a factor of chemical interaction between the particles and ice walls. In this study, anti-freeze proteins (AFPs) are anchored on 1µm-polystyrene (PS) particles, and their behavior in the surface grooves on the ice is studied. The threshold temperature is an effective criterion for evaluating chemical interactions between particles and ice walls. The AFP binding on 1µm PS particles lowers the threshold temperature by 2.5°C, indicating interactions between AFPs on the PS particles and the ice wall. Because the AFPs studied here show selectivity towards the prism plane, it is critical that the prism plane of the ice crystal is in contact with the FCS in the surface grooves. Copyright © 2017 Elsevier B.V. All rights reserved.

Condensation of refrigerants in horizontal, spirally grooved microfin tubes: Numerical analysis of heat transfer in the annular flow regime

Energy Technology Data Exchange (ETDEWEB)

Nozu, S; Honda, H

2000-02-01

A method is presented for estimating the condensation heat transfer coefficient in a horizontal, spirally grooved microfin tube. Based on the flow observation study performed by the authors, a laminar film condensation model in the annular flow regime is proposed. The model assumes that all the condensate flow occurs through the grooves. The condensate film is segmented into thin and thick film regions. In the thin film region formed on the fin surface, the condensate is assumed to be drained by the combined surface tension and vapor shear forces. In the thick film region formed in the groove, on the other hand, the condensate is assumed to be driven by the vapor shear force. The present and previous local heat transfer data including four fluids (CFC11, HCFC22, HCFC123, and HFCl34a) and three microfin tubes are found to agree with the present predictions to a mean absolute deviation of 15.1%.

Heat transfer characteristics for evaporation of R417A flowing inside horizontal smooth and internally grooved tubes

Energy Technology Data Exchange (ETDEWEB)

Xiaoyan, Zhang [School of Energy and Power Engineering, Xi' an Jiaotong University, 28 Xianning Road, Xi' an, Shaanxi 710049 (China); School of Energy Engineering, Xi' an University of Science and Technology, 58 Yanta Street, Xi' an, Shaanxi 710054 (China)], E-mail: gqzxy@sohu.com; Xingqun, Zhang; Yunguang, Chen; Xiuling, Yuan [School of Energy and Power Engineering, Xi' an Jiaotong University, 28 Xianning Road, Xi' an, Shaanxi 710049 (China)

2008-06-15

The experimental study on evaporation heat transfer of R417A (R125/R134a/R600) flowing inside horizontal smooth and two internally grooved tubes with different geometrical parameters was conducted with the mass flow rate range from 176 to 344 kg m{sup -2} s{sup -1}, heat flux from 11 to 32 kW m{sup -2}, evaporation temperature from 0 to 5.5 deg. C and vapor quality from 0.2 to 1. Based on the experimental results, the mechanism and role of the mass flow rate, heat flux, vapor quality and enhanced surface influencing the evaporation heat transfer coefficients were analyzed and discussed. In comparison to R22, the evaporation heat transfer coefficients for R417A were lower and much lower in the internally grooved tubes than in the smooth tube. The present experimental results are also compared with the existing correlations, and the modified Kattan model is found to be in much better agreement with the experimental results than the Kattan model. The Koyama and Wellsandt microfin models all tend to over predict the evaporation heat transfer coefficients rather strongly for R417A inside internally grooved tubes.

Heat transfer characteristics for evaporation of R417A flowing inside horizontal smooth and internally grooved tubes

Energy Technology Data Exchange (ETDEWEB)

Zhang, Xiaoyan [School of Energy and Power Engineering, Xi' an Jiaotong University, 28 Xianning Road, Xi' an, Shaanxi 710049 (China); School of Energy Engineering, Xi' an University of Science and Technology, 58 Yanta Street, Xi' an, Shaanxi 710054 (China); Zhang, Xingqun; Chen, Yunguang; Yuan, Xiuling [School of Energy and Power Engineering, Xi' an Jiaotong University, 28 Xianning Road, Xi' an, Shaanxi 710049 (China)

2008-06-15

The experimental study on evaporation heat transfer of R417A (R125/R134a/R600) flowing inside horizontal smooth and two internally grooved tubes with different geometrical parameters was conducted with the mass flow rate range from 176 to 344 kg m{sup -2} s{sup -1}, heat flux from 11 to 32 kW m{sup -2}, evaporation temperature from 0 to 5.5{sup o}C and vapor quality from 0.2 to 1. Based on the experimental results, the mechanism and role of the mass flow rate, heat flux, vapor quality and enhanced surface influencing the evaporation heat transfer coefficients were analyzed and discussed. In comparison to R22, the evaporation heat transfer coefficients for R417A were lower and much lower in the internally grooved tubes than in the smooth tube. The present experimental results are also compared with the existing correlations, and the modified Kattan model is found to be in much better agreement with the experimental results than the Kattan model. The Koyama and Wellsandt microfin models all tend to over predict the evaporation heat transfer coefficients rather strongly for R417A inside internally grooved tubes. (author)

Heat transfer characteristics for evaporation of R417A flowing inside horizontal smooth and internally grooved tubes

International Nuclear Information System (INIS)

Zhang Xiaoyan; Zhang Xingqun; Chen Yunguang; Yuan Xiuling

2008-01-01

The experimental study on evaporation heat transfer of R417A (R125/R134a/R600) flowing inside horizontal smooth and two internally grooved tubes with different geometrical parameters was conducted with the mass flow rate range from 176 to 344 kg m -2 s -1 , heat flux from 11 to 32 kW m -2 , evaporation temperature from 0 to 5.5 deg. C and vapor quality from 0.2 to 1. Based on the experimental results, the mechanism and role of the mass flow rate, heat flux, vapor quality and enhanced surface influencing the evaporation heat transfer coefficients were analyzed and discussed. In comparison to R22, the evaporation heat transfer coefficients for R417A were lower and much lower in the internally grooved tubes than in the smooth tube. The present experimental results are also compared with the existing correlations, and the modified Kattan model is found to be in much better agreement with the experimental results than the Kattan model. The Koyama and Wellsandt microfin models all tend to over predict the evaporation heat transfer coefficients rather strongly for R417A inside internally grooved tubes

Excitation of fluorescent nanoparticles by channel plasmon polaritons propagating in V-grooves

DEFF Research Database (Denmark)

Cuesta, Irene Fernandez; Nielsen, Rasmus Bundgaard; Boltasseva, Alexandra

2009-01-01

Recently, it has been proven that light can be squeezed into metallic channels with subwavelength lateral dimensions. Here, we present the study of the propagation of channel plasmon polaritons confined in gold V-grooves, filled with fluorescent particles. In this way, channel plasmon polaritons......-diameter beads, we show the possibility of individual excitation, what may have applications to develop very sensitive biosensors....

Evaluation of a Spiral Groove Geometry for Improvement of Hemolysis Level in a Hydrodynamically Levitated Centrifugal Blood Pump.

Science.gov (United States)

Murashige, Tomotaka; Kosaka, Ryo; Sakota, Daisuke; Nishida, Masahiro; Kawaguchi, Yasuo; Yamane, Takashi; Maruyama, Osamu

2015-08-01

The purpose of this study is to evaluate a spiral groove geometry for a thrust bearing to improve the hemolysis level in a hydrodynamically levitated centrifugal blood pump. We compared three geometric models: (i) the groove width is the same as the ridge width at any given polar coordinate (conventional model); (ii) the groove width contracts inward from 9.7 to 0.5 mm (contraction model); and (iii) the groove width expands inward from 0.5 to 4.2 mm (expansion model). To evaluate the hemolysis level, an impeller levitation performance test and in vitro hemolysis test were conducted using a mock circulation loop. In these tests, the driving conditions were set at a pressure head of 200 mm Hg and a flow rate of 4.0 L/min. As a result of the impeller levitation performance test, the bottom bearing gaps of the contraction and conventional models were 88 and 25 μm, respectively. The impeller of the expansion model touched the bottom housing. In the hemolysis test, the relative normalized index of hemolysis (NIH) ratios of the contraction model in comparison with BPX-80 and HPM-15 were 0.6 and 0.9, respectively. In contrast, the relative NIH ratios of the conventional model in comparison with BPX-80 and HPM-15 were 9.6 and 13.7, respectively. We confirmed that the contraction model achieved a large bearing gap and improved the hemolysis level in a hydrodynamically levitated centrifugal blood pump. Copyright © 2015 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

The research of morphological variations and sexual dimorphism of primary grooves on the medial side of brain hemispheres in humans

Directory of Open Access Journals (Sweden)

Spasojević Goran

2012-01-01

Full Text Available Morphological studies of the various parts of the brain show certain morphological and morphometric differences in correlation with sex, so-called sexual dimorphism of the brain. Our research has been done on the cerebral hemispheres, taken from cadavers of both sexes and different age without pathological processes in the brain. The sample comprised 26 male brains and 16 female brains. We studied three primary grooves (sulcus cinguli, sulcus parietooccipitalis and sulcus calcarinus of the medial surface of the human cerebral hemispheres. We conducted morphological typology of grooves and morphometric measurements of primary brain grooves length in relation to sex and side of hemisphere. The results showed a statistically significant sex difference in the cingulate sulcus length (p0,05. Determined morphometric sexual dimorphism in cingulate sulcus length is significant because it implies the correlation between morphology and function of the explored areas of the cerebral cortex.

Hydroelastic response of a floating runway to cnoidal waves

International Nuclear Information System (INIS)

Ertekin, R. C.; Xia, Dingwu

2014-01-01

The hydroelastic response of mat-type Very Large Floating Structures (VLFSs) to severe sea conditions, such as tsunamis and hurricanes, must be assessed for safety and survivability. An efficient and robust nonlinear hydroelastic model is required to predict accurately the motion of and the dynamic loads on a VLFS due to such large waves. We develop a nonlinear theory to predict the hydroelastic response of a VLFS in the presence of cnoidal waves and compare the predictions with the linear theory that is also developed here. This hydroelastic problem is formulated by directly coupling the structure with the fluid, by use of the Level I Green-Naghdi theory for the fluid motion and the Kirchhoff thin plate theory for the runway. The coupled fluid structure system, together with the appropriate jump conditions are solved in two-dimensions by the finite-difference method. The numerical model is used to study the nonlinear response of a VLFS to storm waves which are modeled by use of the cnoidal-wave theory. Parametric studies show that the nonlinearity of the waves is very important in accurately predicting the dynamic bending moment and wave run-up on a VLFS in high seas

Hydroelastic response of a floating runway to cnoidal waves

Energy Technology Data Exchange (ETDEWEB)

Ertekin, R. C., E-mail: ertekin@hawaii.edu [Department of Ocean and Resources Engineering, University of Hawaii at Manoa, Honolulu, Hawaii 96822 (United States); Xia, Dingwu [Engineering Services, British Petroleum GoM, Houston, Texas 77079 (United States)

2014-02-15

The hydroelastic response of mat-type Very Large Floating Structures (VLFSs) to severe sea conditions, such as tsunamis and hurricanes, must be assessed for safety and survivability. An efficient and robust nonlinear hydroelastic model is required to predict accurately the motion of and the dynamic loads on a VLFS due to such large waves. We develop a nonlinear theory to predict the hydroelastic response of a VLFS in the presence of cnoidal waves and compare the predictions with the linear theory that is also developed here. This hydroelastic problem is formulated by directly coupling the structure with the fluid, by use of the Level I Green-Naghdi theory for the fluid motion and the Kirchhoff thin plate theory for the runway. The coupled fluid structure system, together with the appropriate jump conditions are solved in two-dimensions by the finite-difference method. The numerical model is used to study the nonlinear response of a VLFS to storm waves which are modeled by use of the cnoidal-wave theory. Parametric studies show that the nonlinearity of the waves is very important in accurately predicting the dynamic bending moment and wave run-up on a VLFS in high seas.

Analysis of mandibular second molars with fused roots and shallow radicular grooves by using micro-computed tomography.

Science.gov (United States)

Amoroso-Silva, Pablo; De Moraes, Ivaldo Gomes; Marceliano-Alves, Marilia; Bramante, Clovis Monteiro; Zapata, Ronald Ordinola; Hungaro Duarte, Marco Antonio

2018-01-01

This study aimed to describe the morphological and morphometric aspects of fused mandibular second molars with radicular shallow grooves using micro-computed tomography (CT). Eighty-eight mandibular second molars with fused roots were scanned in a micro-CT scanner at a voxel size of 19.6 μm. After reconstruction, only molars without C-shaped roots and presenting shallow radicular grooves were selected. 30 molars were chosen for further analysis. Canal cross-sections were classified according to Fan's modified classification (C1, C2, C3, and C4) and morphometric parameters at the apical region, examination of accessory foramina and tridimensional configuration were evaluated. Three-dimensional reconstructions indicated a higher prevalence of merging type ( n = 22). According to Fan's modified classification, the C4 configuration was predominant in the 3 apical mm. Roundness median values revealed a more round-shaped canals at 3 mm (0.72) than at 2 (0.63) and 1 (0.61) mm from the apex. High values of major and minor diameters were observed in the canals of these evaluated sections. In addition, few accessory apical foramina were observed at 1 and 2 mm from the apex. The average distance between last accessory foramina and the anatomic apex was 1.17 mm. A less complex internal anatomy is found when a mandibular second molar presents fused roots with shallow radicular grooves. The merging type canal was frequently observed. Moreover, the C4 configuration was predominant at a point 3 mm from the apex and presented rounded canals, large apical diameters, and few accessory foramina. The cervical and middle thirds presented C3 and C1 canal configurations most frequently. A minor morphological complexity is found when fused mandibular second molars present shallow radicular grooves.

Large-eddy simulation of flow over a grooved cylinder up to transcritical Reynolds numbers

KAUST Repository

Cheng, W.

2017-11-27

We report wall-resolved large-eddy simulation (LES) of flow over a grooved cylinder up to the transcritical regime. The stretched-vortex subgrid-scale model is embedded in a general fourth-order finite-difference code discretization on a curvilinear mesh. In the present study grooves are equally distributed around the circumference of the cylinder, each of sinusoidal shape with height , invariant in the spanwise direction. Based on the two parameters, and the Reynolds number where is the free-stream velocity, the diameter of the cylinder and the kinematic viscosity, two main sets of simulations are described. The first set varies from to while fixing . We study the flow deviation from the smooth-cylinder case, with emphasis on several important statistics such as the length of the mean-flow recirculation bubble , the pressure coefficient , the skin-friction coefficient and the non-dimensional pressure gradient parameter . It is found that, with increasing at fixed , some properties of the mean flow behave somewhat similarly to changes in the smooth-cylinder flow when is increased. This includes shrinking and nearly constant minimum pressure coefficient. In contrast, while the non-dimensional pressure gradient parameter remains nearly constant for the front part of the smooth cylinder flow, shows an oscillatory variation for the grooved-cylinder case. The second main set of LES varies from to with fixed . It is found that this range spans the subcritical and supercritical regimes and reaches the beginning of the transcritical flow regime. Mean-flow properties are diagnosed and compared with available experimental data including and the drag coefficient . The timewise variation of the lift and drag coefficients are also studied to elucidate the transition among three regimes. Instantaneous images of the surface, skin-friction vector field and also of the three-dimensional Q-criterion field are utilized to further understand the dynamics of the near-surface flow

Measurement repeatability of tibial tuberosity-trochlear groove offset distance in red fox (Vulpes vulpes) cadavers

NARCIS (Netherlands)

Miles, J.E.; Jensen, B.R.; Kirpensteijn, J.; Svalastoga, E.L.; Eriksen, T.

2013-01-01

Abstract OBJECTIVE: To describe CT image reconstruction criteria for measurement of the tibial tuberosity-trochlear groove (TT-TG) offset distance, evaluate intra- and inter-reconstruction repeatability, and identify key sources of error in the measurement technique, as determined in vulpine hind

Contrasting safety assessments of a runway incursion scenario: Event sequence analysis versus multi-agent dynamic risk modelling

International Nuclear Information System (INIS)

Stroeve, Sybert H.; Blom, Henk A.P.; Bakker, G.J.

2013-01-01

In the safety literature it has been argued, that in a complex socio-technical system safety cannot be well analysed by event sequence based approaches, but requires to capture the complex interactions and performance variability of the socio-technical system. In order to evaluate the quantitative and practical consequences of these arguments, this study compares two approaches to assess accident risk of an example safety critical sociotechnical system. It contrasts an event sequence based assessment with a multi-agent dynamic risk model (MA-DRM) based assessment, both of which are performed for a particular runway incursion scenario. The event sequence analysis uses the well-known event tree modelling formalism and the MA-DRM based approach combines agent based modelling, hybrid Petri nets and rare event Monte Carlo simulation. The comparison addresses qualitative and quantitative differences in the methods, attained risk levels, and in the prime factors influencing the safety of the operation. The assessments show considerable differences in the accident risk implications of the performance of human operators and technical systems in the runway incursion scenario. In contrast with the event sequence based results, the MA-DRM based results show that the accident risk is not manifest from the performance of and relations between individual human operators and technical systems. Instead, the safety risk emerges from the totality of the performance and interactions in the agent based model of the safety critical operation considered, which coincides very well with the argumentation in the safety literature.

Final Environmental Assessment for the Proposed Runway 17-35 Closure at Albuquerque International Sunport, Albuquerque, New Mexico

Science.gov (United States)

2011-10-01

34’ ------------------- .... ___ -------------·····-------- --·-----------·---- D-28 U.S. SIEVE OPENING IN INCHES I U.S. SIEVE NUMBERS I HYDROMETER 6 4 3 2 1.5 1 3/4 112...Runway 17-35 Closure Location: Albuquerque International Sunport Number: 1-90703 D-29 U.S. SIEVE OPENING IN INCHES I U.S. SIEVE NUMBERS I HYDROMETER 6...Location: Albuquerque International Sunport ~ (!) Number: 1-90703 ~ D-30 U.S. SIEVE OPENING IN INCHES I U.S. SIEVE NUMBERS I HYDROMETER 6 4 3 2 1.5 1

Flow ripple reduction of an axial piston pump by a combination of cross-angle and pressure relief grooves: Analysis and optimization

International Nuclear Information System (INIS)

Xu, Bing; Ye, Shaogan; Zhang, Junhui; Zhang, Chunfeng

2016-01-01

This paper investigates the potential of flow ripple reduction of an axial piston pump by a combination of cross-angle and pressure relief grooves. A dynamic model is developed to analyze the pumping dynamics of the pump and validated by experimental results. The effects of cross-angle on the flow ripples in the outlet and inlet ports, and the piston chamber pressure are investigated. The effects of pressure relief grooves on the optimal solutions obtained by a multi-objective optimization method are identified. A sensitivity analysis is performed to investigate the sensitivity of cross-angle to different working conditions. The results reveal that the flow ripples from the optimal solutions are smaller using the cross-angle and pressure relief grooves than those using the cross-angle and ordinary precompression and decompression angles and the cross-angle can be smaller. In addition, when the optimal design is used, the outlet flow ripples sensitivity can be reduced significantly.

Rescue and Fire Fighting on RWY 06R/24L

Directory of Open Access Journals (Sweden)

Kristýna Vaňková

2016-04-01

Full Text Available Rescue and firefighting service is an important and essential part at the Václav Havel Airport Prague and it has to follow the requirements stated in Commission regulations (EU, regulations and laws of Czech Republic. Construction of parallel runway 06R/24L influences runway and taxiway system significantly. Consequences of these construction changes are changes of access routes and new places of potential interventions originates. Safety risks of inaccessible areas at the airport and inability to follow response time come with operations of the new runway. These risks are assessed and mitigated if necessary.

Effect of the weld groove shape and pass number on residual stresses in butt-welded pipes

International Nuclear Information System (INIS)

Sattari-Far, I.; Farahani, M.R.

2009-01-01

This study used finite element techniques to analyze the thermo-mechanical behaviour and residual stresses in butt-welded pipes. The residual stresses were also measured in some welds by using the Hole-Drilling method. The results of the finite element analysis were compared with experimentally measured data to evaluate the accuracy of the finite element modelling. Based on this study, a finite element modelling procedure with reasonable accuracy was developed. The developed FE modelling was used to study the effects of weld groove shape and weld pass number on welding residual stresses in butt-welded pipes. The hoop and axial residual stresses in pipe joints of 6 and 10 mm thickness of different groove shapes and pass number were studied. It is shown that these two parameters may have significant effects on magnitude and distribution of residual stresses in welded pipes.

Coronary sinus and atrioventricular groove avulsion after motor vehicle crash

Directory of Open Access Journals (Sweden)

Bradley M Dennis

2014-01-01

Full Text Available Simultaneous cardiac and pericardial rupture from blunt chest trauma is a highly lethal combination with rarely reported survival. We report of a case of young patient with a right atrioventricular groove injury, pericardial rupture and a unique description of a coronary sinus avulsion following blunt chest trauma. Rapid recognition of this injury is crucial to patient survival, but traditional diagnostic adjuncts such as ultrasound, echocardiography and computed tomography are often unhelpful. Successful repair of these injuries requires high suspicion of injury, early cardiac surgery involvement of and possible even placement of the patient on cardiopulmonary bypass.

Constitutional Syndrome, Ascites and Duodenal Thickening Presenting as Groove Pancreatitis

Directory of Open Access Journals (Sweden)

Jose Maria Frutos Perez

2017-12-01

Full Text Available Groove pancreatitis (GP is a very infrequent subtype of chronic pancreatitis affecting the pancreatic-duodenal junction. It usually manifests in middle-aged men with a history of chronic alcoholism, though it has also been described in women and in individuals who do not consume alcohol[1]. Even though the underlying etiology is unclear, chronic alcohol consumption is known to increase the viscosity of the pancreatic juice and exacerbate the inflammatory process[2]. We present a case of GP that posed diagnostic difficulties because it manifested as ascites and duodenal thickening, with pancreatic imaging findings initially normal.

Hybrid plasmonic waveguide in a metal V-groove

Directory of Open Access Journals (Sweden)

Zhao-xian Chen

2014-01-01

Full Text Available We propose and investigate a type of hybrid plasmonic waveguide in a metal V-groove. A high-permittivity nanowire was placed in the metal channel covered with a dielectric film of lower permittivity. Deeper sub-wavelength confinement and much longer propagation distance were achieved in comparison with conventional channel plasmonic waveguides. The overall performance was improved as compared with the conventional hybrid plasmonic structure based on a flat metal surface. Finite element analysis showed that both the mode propagation and field profile can be adjusted by changing the nanowire radius and film thickness. Some benefits, such as a reduced scattering loss caused by the surface roughness, are also expected owing to the unique mode profile. The proposed approach has potential for application in high-level photonic integration.

Chaotic Behaviour Investigation of a Front Opposed-Hemispherical Spiral-Grooved Air Bearing System

Directory of Open Access Journals (Sweden)

Cheng-Chi Wang

2017-01-01

Full Text Available In recent years, spiral-grooved air bearing systems have attracted much attention and are especially useful in precision instruments and machines with spindles that rotate at high speed. Load support can be multidirectional and this type of bearing can also be very rigid. Studies show that some of the design problems encountered are dynamic and include critical speed, nonlinearity, gas film pressure, unbalanced rotors, and even poor design, all of which can result in the generation of chaotic aperiodic motion and instability under certain conditions. Such irregular motion on a large scale can cause severe damage to a machine or instrument. Therefore, understanding the conditions under which aperiodic behaviour and vibration arise is crucial for prevention. In this study, numerical analysis, including the Finite Difference and Differential Transformation Methods, is used to study these effects in detail in a front opposed-hemispherical spiral-grooved air bearing system. It was found that different rotor masses and bearing number could cause undesirable behaviour including periodic, subperiodic, quasi-periodic, and chaotic motion. The results obtained in this study can be used as a basis for future bearing system design and the prevention of instability.

Acute radial nerve entrapment at the spiral groove: detection by DTI-based neurography

Energy Technology Data Exchange (ETDEWEB)

Jengojan, Suren; Breitenseher, Julia; Weber, Michael; Prayer, Daniela; Kasprian, Gregor [Medical University of Vienna, Department of Biomedical Imaging and Image-guided Therapy, Division of Neuro- and Musculosceletal Radiology, Vienna (Austria); Kovar, Florian [Medical University of Vienna, Department of Trauma-Surgery, Vienna (Austria)

2015-06-01

This study evaluated the potential of three-tesla diffusion tensor imaging (DTI) and tractography to detect changes of the radial (RN) and median (MN) nerves during transient upper arm compression by a silicon ring tourniquet. Axial T2-weighted and DTI sequences (b = 700 s/mm{sup 2}, 16 gradient encoding directions) of 13 healthy volunteers were obtained. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values of the MN and RN were measured at the spiral groove and further visualized in 3D by deterministic tractography (thresholds: FA =.15, angle change = 27 ). Local/lesional RN FA values increased (p = 0.001) and ADC values decreased (p = 0.02) during a 20-min upper arm compression, whereas no significant FA (p = 0.49) or ADC (p = 0.73) changes of the MN were detected. There were no T2-w nerve signal changes or alterations of nerve trajectories in 3D. Acute nerve compression of the RN leads to changes of its three-tesla DTI metrics. Peripheral nerve DTI provides non-invasive insights into the ''selective'' vulnerability of the RN at the spiral groove. (orig.)

Effect on Bone Architecture of Marginal Grooves in Dental Implants Under Occlusal Loaded Conditions in Beagle Dogs.

Science.gov (United States)

Kato, Hatsumi; Kuroshima, Shinichiro; Inaba, Nao; Uto, Yusuke; Sawase, Takashi

2018-02-01

The aim of this study was to clarify whether marginal grooves on dental implants affect osseointegration, bone structure, and the alignment of collagen fibers to determine bone quality under loaded conditions. Anodized Ti-6Al-4V alloy dental implants, with and without marginal grooves (test and control implants, respectively), were used (3.7 × 8.0 mm). Fourth premolars and first molars of 6 beagle mandibles were extracted. Two control and test implants were placed in randomly selected healed sites at 12 weeks after tooth extraction. Screw-retained single crowns for first molars were fabricated. Euthanasia was performed at 8 weeks after the application of occlusal forces. Implant marginal bone level, bone to implant contact (BIC), bone structure around dental implants, and the alignment of collagen fibers determining bone quality were analyzed. The marginal bone level in test implants was significantly higher than that in control implants. Occlusal forces significantly increased BIC in test implants ( P = .007), whereas BIC did not change in control implants, irrespective of occlusal forces ( P = .303). Moreover, occlusal forces significantly increased BIC in test implants compared with control implants ( P = .032). Additionally, occlusal forces preferentially aligned collagen fibers in test implants, but not control implants. Hence, marginal grooves on dental implants have positive effects on increased osseointegration and adapted bone quality based on the preferential alignment of collagen fibers around dental implants under loaded conditions.

Sequence-specific high mobility group box factors recognize 10-12-base pair minor groove motifs

DEFF Research Database (Denmark)

van Beest, M; Dooijes, D; van De Wetering, M

2000-01-01

Sequence-specific high mobility group (HMG) box factors bind and bend DNA via interactions in the minor groove. Three-dimensional NMR analyses have provided the structural basis for this interaction. The cognate HMG domain DNA motif is generally believed to span 6-8 bases. However, alignment...

A comparison of step-and-shoot leaf sequencing algorithms that eliminate tongue-and-groove effects

Energy Technology Data Exchange (ETDEWEB)

Kamath, Srijit [Department of Computer and Information Science and Engineering, University of Florida, Gainesville, FL (United States); Sahni, Sartaj [Department of Computer and Information Science and Engineering, University of Florida, Gainesville, FL (United States); Ranka, Sanjay [Department of Computer and Information Science and Engineering, University of Florida, Gainesville, FL (United States); Li, Jonathan [Department of Radiation Oncology, University of Florida, Gainesville, FL (United States); Palta, Jatinder [Department of Radiation Oncology, University of Florida, Gainesville, FL (United States)

2004-07-21

The performances of three recently published leaf sequencing algorithms for step-and-shoot intensity-modulated radiation therapy delivery that eliminates tongue-and-groove underdosage are evaluated. Proofs are given to show that the algorithm of Que et al (2004 Phys. Med. Biol. 49 399-405) generates leaf sequences free of tongue-and-groove underdosage and interdigitation. However, the total beam-on times could be up to n times those of the sequences generated by the algorithms of Kamath et al (2004 Phys. Med. Biol. 49 N7-N19), which are optimal in beam-on time for unidirectional leaf movement under the same constraints, where n is the total number of involved leaf pairs. Using 19 clinical fluence matrices and 100 000 randomly generated 15 x 15 matrices, the average monitor units and number of segments of the leaf sequences generated using the algorithm of Que et al are about two to four times those generated by the algorithm of Kamath et al.

A comparison of step-and-shoot leaf sequencing algorithms that eliminate tongue-and-groove effects

International Nuclear Information System (INIS)

Kamath, Srijit; Sahni, Sartaj; Ranka, Sanjay; Li, Jonathan; Palta, Jatinder

2004-01-01

The performances of three recently published leaf sequencing algorithms for step-and-shoot intensity-modulated radiation therapy delivery that eliminates tongue-and-groove underdosage are evaluated. Proofs are given to show that the algorithm of Que et al (2004 Phys. Med. Biol. 49 399-405) generates leaf sequences free of tongue-and-groove underdosage and interdigitation. However, the total beam-on times could be up to n times those of the sequences generated by the algorithms of Kamath et al (2004 Phys. Med. Biol. 49 N7-N19), which are optimal in beam-on time for unidirectional leaf movement under the same constraints, where n is the total number of involved leaf pairs. Using 19 clinical fluence matrices and 100 000 randomly generated 15 x 15 matrices, the average monitor units and number of segments of the leaf sequences generated using the algorithm of Que et al are about two to four times those generated by the algorithm of Kamath et al

Large critical current density improvement in Bi-2212 wires through the groove-rolling process

International Nuclear Information System (INIS)

Malagoli, A; Bernini, C; Braccini, V; Romano, G; Putti, M; Chaud, X; Debray, F

2013-01-01

Recently there has been a growing interest in Bi-2212 superconductor round wire for high magnetic field use despite the fact that an increase of the critical current is still needed to boost its successful use in such applications. Recent studies have demonstrated that the main obstacle to current flow, especially in long wires, is the residual porosity inside these powder-in-tube processed conductors that develops from bubble agglomeration when the Bi-2212 melts. In this work we tried to overcome this issue affecting the wire densification by changing the deformation process. Here we show the effects of groove rolling versus the drawing process on the critical current density J C and on the microstructure. In particular, groove-rolled multifilamentary wires show a J C increased by a factor of about 3 with respect to drawn wires prepared with the same Bi-2212 powder and architecture. We think that this approach in the deformation process is able to produce the required improvements both because the superconducting properties are enhanced and because it makes the fabrication process faster and cheaper. (paper)

Quantitative structure of a complex between a minor-groove-specific drug and a bent DNA decamer duplex: Use of 2D NMR data and NOESY constrained energy minimization

International Nuclear Information System (INIS)

Sarma, M.H.; Gupta, G.; Garcia, A.E.; Umemoto, K.; Sarma, R.H.

1990-01-01

Two-dimensional nuclear magnetic resonance (2D NMR) studies on d(GA4T4C)2 and d(GT4A4C)2 showed that A.T pairs are propeller twisted. As a result, A/T tracts form a straight rigid structural block with an array of bifurcated inter base pair H bonds in the major groove. It was demonstrated (previous paper) that replacement of methyl group by hydrogen (changing from T to U) in the major groove does not disrupt the array of bifurcated H bonds in the major groove. In this article, we summarize results of 2D NMR and molecular mechanic studies on the effect of a minor-groove-binding A.T-specific drug on the structure d(GA4T4C)2. A distamycin analogue (Dst2) was used for this study. It is shown that Dst2 binds to the minor groove of d(GA4T4C)2 mainly driven by van der Waals interaction between A.T pairs and the drug; as a consequence, an array of bifurcated H bonds can be formed in the minor groove between amide/amino protons of Dst2 and A.T pairs of DNA. NOESY data suggest that Dst2 predominantly binds at the central 5 A.T pairs. NOESY data also reveal that, upon drug binding, d(GA4T4C)2 does not undergo any significant change in conformation from the free state; i.e., propeller-twisted A.T pairs are still present in DNA and hence the array of bifurcated H bonds must be preserved in the major groove. NOESY data for the A5-T6 sequence also indicate that there is little change in junction stereochemistry upon drug binding

Tool wear of a single-crystal diamond tool in nano-groove machining of a quartz glass plate

International Nuclear Information System (INIS)

Yoshino, Masahiko; Nakajima, Satoshi; Terano, Motoki

2015-01-01

Tool wear characteristics of a diamond tool in ductile mode machining are presented in this paper. Nano-groove machining of a quartz glass plate was conducted to examine the tool wear rate of a single-crystal diamond tool. Effects of lubrication on the tool wear rate were also evaluated. A numerical simulation technique was developed to evaluate the tool temperature and normal stress acting on the wear surface. From the simulation results it was found that the tool temperature does not increase during the machining experiment. It is also demonstrated that tool wear is attributed to the abrasive wear mechanism, but the effect of the adhesion wear mechanism is minor in nano-groove machining. It is found that the tool wear rate is reduced by using water or kerosene as a lubricant. (paper)

Environmental Assessment for Repair of Airfield Pavement and Lighting, Runway 03R/21L Travis Air Force Base, Fairfield, California. Revision

Science.gov (United States)

2009-12-01

substandard: 211450 SM PROJECT: Repair Runway 03R-21L pavements, airfield lighting, fiber optic communication lines , markers, and drainage systems...bottomed swales, or basalt flow depression pools in unplowed grasslands. The fairy shrimp has been collected from early December to early May. It can...pool types where the species has been found include Northern Hardpan, Northern Claypan, Northern Volcanic Mud Flow, and Northern Basalt Flow vernal

Micro-CT evaluation of root and canal morphology of mandibular first premolars with radicular grooves

Energy Technology Data Exchange (ETDEWEB)

Boschetti, Emanuele; Mazzi-Chaves, Jardel Francisco; Versiani, Marco Aurélio; Pécora, Jesus Djalma; Saquy, Paulo Cesar; Sousa Neto, Manoel Damião de, E-mail: sousanet@forp.usp.br [Universidade de São Paulo (USP), Ribeirao Preto, SP (Brazil). Departamento de Odontologia Restauradora; Silva-Sousa, Yara Terezinha Correa; Leoni, Graziela Bianchi [Universidade de Ribeirão Preto (UNAERP), Ribeirão Preto, SP (Brazil). Departmento de Endodontia

2017-09-15

The aim of this study was to evaluate morphological features of 70 single-rooted mandibular first premolars with radicular grooves (RG) using micro-CT technology. Teeth were scanned and evaluated regarding the morphology of the roots and root canals as well as length, depth and percentage frequency location of the RG. Volume, surface area and Structure Model Index (SMI) of the canals were measured for the full root length. Two-dimensional parameters and frequency of canal orifices were evaluated at 1, 2, and 3 mm levels from the apical foramen. The number of accessory canals, the dentin thickness, and cross-sectional appearance of the canal at different root levels were also recorded. Expression of deep grooves was observed in 21.42% of the sample. Mean lengths of root and RG were 13.43 mm and 8.5 mm, respectively, while depth of the RG ranged from 0.75 to 1.13 mm. Mean canal volume, surface area and SMI were 10.78 mm{sup 3}, 58.51 mm{sup 2}, and 2.84, respectively. Apical delta was present in 4.35% of the sample and accessory canals were observed mostly at the middle and apical thirds. Two-dimensional parameters indicated an oval-shaped cross-sectional appearance of the root canal with a high percentage frequency of canal divisions (87.15%). Canal configuration type V (58.57%) was the most prevalent. C-shaped configuration was observed in 13 premolars (18.57%), whereas dentin thickness ranged from 1.0 to 1.31 mm. Radicular grooves in mandibular first premolars was associated with the occurrence of several anatomical complexities, including C-shaped canals and divisions of the main root canal. (author)

Micro-CT evaluation of root and canal morphology of mandibular first premolars with radicular grooves

International Nuclear Information System (INIS)

Boschetti, Emanuele; Mazzi-Chaves, Jardel Francisco; Versiani, Marco Aurélio; Pécora, Jesus Djalma; Saquy, Paulo Cesar; Sousa Neto, Manoel Damião de; Silva-Sousa, Yara Terezinha Correa; Leoni, Graziela Bianchi

2017-01-01

The aim of this study was to evaluate morphological features of 70 single-rooted mandibular first premolars with radicular grooves (RG) using micro-CT technology. Teeth were scanned and evaluated regarding the morphology of the roots and root canals as well as length, depth and percentage frequency location of the RG. Volume, surface area and Structure Model Index (SMI) of the canals were measured for the full root length. Two-dimensional parameters and frequency of canal orifices were evaluated at 1, 2, and 3 mm levels from the apical foramen. The number of accessory canals, the dentin thickness, and cross-sectional appearance of the canal at different root levels were also recorded. Expression of deep grooves was observed in 21.42% of the sample. Mean lengths of root and RG were 13.43 mm and 8.5 mm, respectively, while depth of the RG ranged from 0.75 to 1.13 mm. Mean canal volume, surface area and SMI were 10.78 mm 3 , 58.51 mm 2 , and 2.84, respectively. Apical delta was present in 4.35% of the sample and accessory canals were observed mostly at the middle and apical thirds. Two-dimensional parameters indicated an oval-shaped cross-sectional appearance of the root canal with a high percentage frequency of canal divisions (87.15%). Canal configuration type V (58.57%) was the most prevalent. C-shaped configuration was observed in 13 premolars (18.57%), whereas dentin thickness ranged from 1.0 to 1.31 mm. Radicular grooves in mandibular first premolars was associated with the occurrence of several anatomical complexities, including C-shaped canals and divisions of the main root canal. (author)

Determination of Tongue and Groove parameters for multileaf collimators; Determinaco de parametros de Tongue and Groove de colimadores de multilaminas

Energy Technology Data Exchange (ETDEWEB)

Castro, Aluisio; Almeida, Carlos E. de, E-mail: alu_neto@hotmail.com [Universidade Estadual do Rio de Janeiro (UERJ), RJ (Brazil). Laboratorio de Ciencias Radiologicas; Nguyen, Bihn [Prowess Inc., Concord, CA (United States)

2012-08-15

The Tongue and Groove effect (TandG) is characterized by an additional attenuation between adjacent and opposing leaves on multileaf collimators (MLCs) in adjacent or complementary fields. This is a typical situation in of intensity-modulated radiotherapy treatments. The aim of this study was to measure the width and transmission of TandG effect for two commercial MLCs: Varian Millennium 120 (6 MV and 16 MV beams) and BrainLab m3 (only for 6 MV). The methodology used was based on the creation of MLC shapes that emphasizes TandG effect, the irradiation of these fields on radiochromic film and the sensitometric evaluation of the films in order to determine the TandG width and transmission. The results for TandG width for studied MLCs were 2.5, 1.8 and 2 mm, respectively, whit transmission TandG values of 87, 90 and 85%. (author)

Tube with helical grooving for a heat exchanger and its manufacturing process

International Nuclear Information System (INIS)

Yampolsky, J.S.

1980-01-01

This claim broadly concerns heat transfer tubes for heat exchangers of the kind described in the main patent specification and, in particular, a heat transfer tube and a process for manufacturing it. This tube includes a strip of metal, the opposite sides of which extend to form a certain number of longitudinal grooves of specific profile and height. This strip is helically wound and the lateral edges are joined butt to butt so as to be leak tight to fluids [fr

Accomplishments under the Airport Improvement Program: Fiscal Year 1988

Science.gov (United States)

1988-01-01

WIND (PRIMARY) INDICATOR; SECURITY FENCING HOLBROOK 02 $22,766 CONDUCT MASTER PLAN UPDATE HOLBROOK MUNICIPAL (GENERAL AVIATION) KAYENTA 03 $1,238,484...CONSTRUCT RUNWAY, TAXIWAY, APRON AND KAYENTA ACCESS ROAD; INSTALL RUNWAY AND TAXIWAY (GENERAL AVIATION) LIGHTING SYSTEM, VISUAL APPROACH INDICATOR

Research on Degeneration Model of Neural Network for Deep Groove Ball Bearing Based on Feature Fusion

Directory of Open Access Journals (Sweden)

Lijun Zhang

2018-02-01

Full Text Available Aiming at the pitting fault of deep groove ball bearing during service, this paper uses the vibration signal of five different states of deep groove ball bearing and extracts the relevant features, then uses a neural network to model the degradation for identifying and classifying the fault type. By comparing the effects of training samples with different capacities through performance indexes such as the accuracy and convergence speed, it is proven that an increase in the sample size can improve the performance of the model. Based on the polynomial fitting principle and Pearson correlation coefficient, fusion features based on the skewness index are proposed, and the performance improvement of the model after incorporating the fusion features is also validated. A comparison of the performance of the support vector machine (SVM model and the neural network model on this dataset is given. The research shows that neural networks have more potential for complex and high-volume datasets.

Secondary Electron Yield Measurements and Groove Chambers Tests in the PEP-II Beam Line Straights Sections

International Nuclear Information System (INIS)

Pivi, M

2008-01-01

Beam instability caused by the electron cloud has been observed in positron and proton storage rings and it is expected to be a limiting factor in the performance of the positron Damping Ring (DR) of future Linear Colliders such as ILC and CLIC [1, 2]. In the Positron Low Energy Ring (LER) of the PEP-II accelerator, we have installed vacuum chambers with rectangular grooves in a straight magnetic-free section to test this promising possible electron cloud mitigation technique. We have also installed a special chamber to monitor the secondary electron yield of TiN and TiZrV (NEG) coating, Copper, Stainless Steel and Aluminum under the effect of electron and photon conditioning in situ in the beam line. In this paper, we describe the ongoing R and D effort to mitigate the electron cloud effect for the ILC damping ring, the latest results on in situ secondary electron yield conditioning and recent update on the groove tests in PEP-II

Modern Microsurgical Resection of Olfactory Groove Meningiomas by Classical Bicoronal Subfrontal Approach without Orbital Osteotomies.

Science.gov (United States)

Farooq, Ghulam; Rehman, Lal; Bokhari, Irum; Rizvi, Syed Raza Hussain

2018-01-01

The olfactory groove meningioma has always been surgically challenging. The common microscopic surgical procedures exercised involve modification of pterional or sub-frontal approaches with or without orbital osteotomies. However, we believe that orbital osteotomies are not mandatory to achieve gross total resection. Hence, this study was performed to evaluate the surgical outcomes of olfactory groove meningioma with bicoronal sub frontal approach but without orbital osteotomies. The study was performed by reviewing the medical charts, neuroimaging data, and follow-up data of 19 patients who were treated micro surgically for olfactory groove meningioma without orbital osteotomies in our department. Mean overall follow up period of our study was 5 years. Statistical analysis was done by means of IBM SPSS Software version 19. Nineteen patients (1 male and 18 female patients, with an age range of 35-67 years; average age of patients' 51±7.5 years) of OGM were managed in our department. All patients were evaluated by MRI Brain with and without Gadolinium, CTA, CT Scan both axial and Coronal sequences. Most common symptom reported was head ache (80%), others include; urinary incontinence (26%), seizures (78%), decreased visual acuity (79%), papilledema (74%), personality changes (68%) and olfactory loss was reported in 57% of the patients. Post-operative complications include; CSF accumulation (5%), hematoma at tumor bed (10%), skin infection (5%) and mild post-operative brain edema (26%). Mortality rate was 5%. During 5 years of follow-up, we recorded one recurrence which was after 26 months and successfully removed in reoperation. Bi-coronal sub frontal approach appears to be an excellent technique for Olfactory Meningioma removal as practiced by most neurosurgeons. Nevertheless, it is not mandatory to carry out orbital osteotomy to acquire optimal surgical outcome as is advocated by some Authors.

Does Loading Influence the Severity of Cartilage Degeneration in the Canine Groove-Model of OA?

NARCIS (Netherlands)

Vos, Petra; Intema, Femke; van El, Benno; DeGroot, Jeroen; Bijlsma, J. W. J.; Lafeber, Floris; Mastbergen, Simon

2009-01-01

Many animal models are used to study osteoarthritis (OA). In these models the role of joint loading in the development of CA is not fully understood. We studied the effect of loading on the development of CIA in the canine Groove-model. In ten female beagle dogs OA was induced in one knee according

Grooves to tubes: evolution of the venom delivery system in a Late Triassic "reptile"

Science.gov (United States)

Mitchell, Jonathan S.; Heckert, Andrew B.; Sues, Hans-Dieter

2010-12-01

Venom delivery systems occur in a wide range of extant and fossil vertebrates and are primarily based on oral adaptations. Teeth range from unmodified (Komodo dragons) to highly specialized fangs similar to hypodermic needles (protero- and solenoglyphous snakes). Developmental biologists have documented evidence for an infolding pathway of fang evolution, where the groove folds over to create the more derived condition. However, the oldest known members of venomous clades retain the same condition as their extant relatives, resulting in no fossil evidence for the transition. Based on a comparison of previously known specimens with newly discovered teeth from North Carolina, we describe a new species of the Late Triassic archosauriform Uatchitodon and provide detailed analyses that provide evidence for both venom conduction and document a complete structural series from shallow grooves to fully enclosed tubular canals. While known only from teeth, Uatchitodon is highly diagnostic in possessing compound serrations and for having two venom canals on each tooth in the dentition. Further, although not a snake, Uatchitodon sheds light on the evolutionary trajectory of venom delivery systems in amniotes and provide solid evidence for venom conduction in archosaur-line diapsids.

Accomplishments Under the Airport Improvement Program. Fiscal year 1987.

Science.gov (United States)

1987-01-01

PREPARATION); GRAND CANYON NATIONAL PARK ACQUIRE LAND FOR APPROACHES; INSTALL (PRIMARY) FENCING KAYENTA 02 $561,695 CONSTRUCT NEW RUNWAY, TAXIWAY AND...APRON KAYENTA (SITE PREPARATION) (GENERAL AVIATION) KINGMAN 04 $138,411 INSTALL RUNWAY LIGHTING, TAXIWAY MOHAVE COUNTY GUIDANCE SIGNS AND VISUAL APPROACH

Experimental investigation of turbulent flow past four grooved and smooth cylinders in an in-line square arrangement

Directory of Open Access Journals (Sweden)

Ladjedel O.

2015-01-01

Full Text Available An experimental study of turbulent flow past four cylinders in square arrangement with a space ratio of (T/D = P/D = 2.88 is performed. The investigation focuses on effects of Reynolds number and the shape of cylinders on the force and pressure coefficients of the cylinders. Two cases are investigated: four smooth cylinders (case1 and four grooved cylinders (case2. The cylinders are equipped with two grooves placed on the external surface at 90° and 270° degrees. The pressure distributions along the tubes (22 circumferential pressure taping were determined for a variation of the azimuthal angle from 0 to 360deg. The drag and lift forces are measured using the TE 44 balance. The results show a bistable flow often exists behind the downstream cylinders is observed. By rising the Reynolds number the pressure coefficient increases in the absolute value.

From old alkylating agents to new minor groove binders.

Science.gov (United States)

Puyo, Stéphane; Montaudon, Danièle; Pourquier, Philippe

2014-01-01

Alkylating agents represent the oldest class of anticancer agents with the approval of mechloretamine by the FDA in 1949. Even though their clinical use is far beyond the use of new targeted therapies, they still occupy a major place in the treatment of specific malignancies, sometimes representing the unique option for the treatment of refractory tumors. Here, we are reviewing the major classes of alkylating agents, with a particular focus on the latest generations of compounds that specifically target the minor groove of the DNA. These naturally occurring derivatives have a unique mechanism of action that explains the recent regain of interest in developing new classes of alkylating agents that could be used in combination with other anticancer drugs to enhance tumor response in the clinic. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Influence of Divalent Counterions on the Dynamics in DNA as Probed by Using a Minor-Groove Binder.

Science.gov (United States)

Paul, Sneha; Ahmed, Tasnim; Samanta, Anunay

2017-08-05

DNA dynamics, to which water, counterions, and DNA motions contribute, is a topic of considerable interest because it is closely related to the efficiency of biological functions performed by it. Simulation studies and experiments suggest that the counterion dynamics in DNA probed by a minor-groove binder are similar for various monovalent counterions. To date, the influence on DNA dynamics of higher-valence counterions, which are also present around DNA and are known to bind more strongly to it than monovalent ions, has not been studied. Herein we investigated DNA dynamics in the presence of Mg 2+ and Ca 2+ , chosen for their relative abundance in cells, by using minor-groove binder 4',6-diamidino-2-phenylindole (DAPI) as a fluorescence probe. The dynamics, as measured from the time-resolved fluorescence Stokes shifts of DAPI bound to calf thymus DNA on a subpicosecond-to-nanosecond timescale, were found to be very similar in the presence of both the divalent ions and Na + ions. The observation is explained by considering the screening of the electric field of the divalent ion by its hydration shell, preferential binding of the ions to the phosphate groups, and displacement of ions from the minor groove by DAPI due to the stronger binding interaction of the latter. Furthermore, the similarity of our results in the presence of Na + to those reported for smaller oligonucleotides suggests that the chain length of DNA does not influence the DNA dynamics. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effects of Gas Rarefaction on Dynamic Characteristics of Micro Spiral-Grooved Thrust Bearing

OpenAIRE

Liu, Ren; Wang, Xiao-Li; Zhang, Xiao-Qing

2012-01-01

The effects of gas-rarefaction on dynamic characteristics of micro spiral-grooved-thrust-bearing are studied. The Reynolds equation is modified by the first order slip model, and the corresponding perturbation equations are then obtained on the basis of the linear small perturbation method. In the converted spiral-curve-coordinates system, the finite-volume-method (FVM) is employed to discrete the surface domain of micro bearing. The results show, compared with the continuum-flow model, that ...

Technology and function of grooved abraders in the early Neolithic of northwestern Europe

Directory of Open Access Journals (Sweden)

Caroline Hamon

2016-10-01

Full Text Available Found sporadically in late Palaeolithic and Mesolithic contexts, grooved abraders are among the most common tools found in Linear Pottery and Villeneuve-Saint-Germain settlements in north-western Europe (5,100-4,700 BCE. This paper presents an overview of the technical and functional characteristics of these tools in early Neolithic domestic contexts. Despite different blank morphologies and sizes, these tools tend to be relatively small in size and are generally not shaped. They are characterized by the use of a very specific raw material: low cohesive and generally ferruginous sandstones, chosen because their abrasiveness is enhanced through use. A classification of the different types of grooves is proposed, based on their shape, depth, section and localization. These characteristics are combined with use-wear analysis in order to propose a number of functional interpretations. Far from the widespread hypothesis that these tools functioned as shaft straighteners, we argue on the basis of the use-wear analysis and archaeological associations of items that these tools were primarily involved in the manufacture of bone and lithic tools, as well as of schist and limestone personal ornaments. They are evidence of the generalization and diversification of polishing and abrading techniques in the technical system of the first Neolithic populations. As such, they contribute to defining a whole new technical paradigm and are an essential element in any definition of the Neolithic.

Condensation and evaporation transitions in deep capillary grooves

International Nuclear Information System (INIS)

Malijevský, Alexandr; Parry, Andrew O

2014-01-01

We study the order of capillary condensation and evaporation transitions of a simple fluid adsorbed in a deep capillary groove using a fundamental measure density functional theory (DFT). The walls of the capillary interact with the fluid particles via long-ranged, dispersion, forces while the fluid-fluid interaction is modelled as a truncated Lennard–Jones-like potential. We find that below the wetting temperature T w condensation is first-order and evaporation is continuous with the metastability of the condensation being well described by the complementary Kelvin equation. In contrast above T w both phase transitions are continuous and their critical singularities are determined. In addition we show that for the evaporation transition above T w there is an elegant mapping, or covariance, with the complete wetting transition occurring at a planar wall. Our numerical DFT studies are complemented by analytical slab model calculations which explain how the asymmetry between condensation and evaporation arises out of the combination of long-ranged forces and substrate geometry. (paper)

Condensation and evaporation transitions in deep capillary grooves.

Science.gov (United States)

Malijevský, Alexandr; Parry, Andrew O

2014-09-03

We study the order of capillary condensation and evaporation transitions of a simple fluid adsorbed in a deep capillary groove using a fundamental measure density functional theory (DFT). The walls of the capillary interact with the fluid particles via long-ranged, dispersion, forces while the fluid-fluid interaction is modelled as a truncated Lennard-Jones-like potential. We find that below the wetting temperature Tw condensation is first-order and evaporation is continuous with the metastability of the condensation being well described by the complementary Kelvin equation. In contrast above Tw both phase transitions are continuous and their critical singularities are determined. In addition we show that for the evaporation transition above Tw there is an elegant mapping, or covariance, with the complete wetting transition occurring at a planar wall. Our numerical DFT studies are complemented by analytical slab model calculations which explain how the asymmetry between condensation and evaporation arises out of the combination of long-ranged forces and substrate geometry.

Olfactory groove meningioma: discussion of clinical presentation and surgical outcomes following excision via the subcranial approach.

Science.gov (United States)

Pepper, Jon-Paul; Hecht, Sarah L; Gebarski, Stephen S; Lin, Erin M; Sullivan, Stephen E; Marentette, Lawrence J

2011-11-01

To describe surgical outcomes and radiographic features of olfactory groove meningiomas treated by excision through the subcranial approach. Special emphasis is placed on paranasal sinus and orbit involvement. Retrospective review of a series of patients. Nineteen patients underwent excision of olfactory groove meningioma (OGM) via the transglabellar/subcranial approach between December 1995 and November 2009. Nine patients had previously undergone prior resection at outside institutions, and four had prior radiotherapy in addition to a prior excision. Transglabellar/subcranial surgical approach to the anterior skull base was performed. Tumor histology included three World Health Organization (WHO) grade III lesions, one WHO grade II lesion, and 15 WHO grade I lesions. Fourteen patients had evidence of extension into the paranasal sinuses, with the ethmoid sinus being most commonly involved. Kaplan-Meier estimates of mean overall and disease-free survival were 121.45 months and 93.03 months, respectively. The mean follow-up interval was 41.0 months, and at the time of data analysis three patients had recurrent tumors. Seven (36.8%) patients experienced a major complication in the perioperative period; there were no perioperative mortalities. Orbit invasion was observed in four patients, with optic nerve impingement in 11 patients. Of these, three patients had long-term diplopia. No patients experienced worsening of preoperative visual acuity. Olfactory groove meningiomas demonstrate a propensity to spread into the paranasal sinuses, particularly in recurrent cases. Given a tendency for infiltrative recurrence along the skull base, this disease represents an important area of collaboration between neurosurgery and otolaryngology. The subcranial approach offers excellent surgical access for excision, particularly for recurrences that involve the paranasal sinuses and optic apparatus. Copyright © 2011 The American Laryngological, Rhinological, and Otological Society

Reduction of absorption loss in multicrystalline silicon via combination of mechanical grooving and porous silicon

Energy Technology Data Exchange (ETDEWEB)

Ben Rabha, Mohamed; Mohamed, Seifeddine Belhadj; Dimassi, Wissem; Gaidi, Mounir; Ezzaouia, Hatem; Bessais, Brahim [Laboratoire de Photovoltaique, Centre de Recherches et des Technologies de l' Energie, Technopole de Borj-Cedria, BP 95, 2050 Hammam-Lif (Tunisia)

2011-03-15

Surface texturing of silicon wafer is a key step to enhance light absorption and to improve the solar cell performances. While alkaline-texturing of single crystalline silicon wafers was well established, no efficient chemical solution has been successfully developed for multicrystalline silicon wafers. Thus, the use of alternative new methods for effective texturization of multicrystalline silicon is worth to be investigated. One of the promising texturing techniques of multicrystalline silicon wafers is the use of mechanical grooves. However, most often, physical damages occur during mechanical grooves of the wafer surface, which in turn require an additional step of wet processing-removal damage. Electrochemical surface treatment seems to be an adequate solution for removing mechanical damage throughout porous silicon formation. The topography of untreated and porous silicon-treated mechanically textured surface was investigated using scanning electron microscopy (SEM). As a result of the electrochemical surface treatment, the total reflectivity drops to about 5% in the 400-1000 nm wavelength range and the effective minority carrier diffusion length enhances from 190 {mu}m to about 230 {mu}m (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

High strain rate mechanical response of buttress-grooved tensile specimens which have undergone environmental exposure

International Nuclear Information System (INIS)

Weirick, L.J.

1976-07-01

The purpose of the corrosion compatibility program was to identify the effect of corrosion on the mechanical performance of the buttress-grooved section of the 105-mm penetrator, a section which must sustain a load during launch. It is important that the environment not deteriorate the mechanical integrity of these grooves during long-term storage. Both coated and uncoated test specimens which simulate both geometrical shape and residual stress patterns were exposed to corrosive environments of moist air, distilled water, and salt water. Some of these tests also incorporated the galvanic coupling caused by the aluminum sabot. After exposure to the corrosive environments, the specimens were pulled on a high strain rate tensile machine which simulated launch conditions. Results show that the galvanic coupling due to the aluminum sabot caused no deterioration of mechanical properties. Results do indicate that the coating applied caused a significant reduction in the fracture load. There was a dichotomy in the results as affected by the environment. Uncoated test specimens showed no change in fracture load with increasing severity of corrosion environment, whereas the coated specimens indicated a trend of decreasing load-bearing ability with increasing corrosion

Numerical Analysis of Fully Developed Laminar Flow in Trapezoidal and Sinusoidal Grooves with Shear Stress at the Liquid-Vapor Interface

National Research Council Canada - National Science Library

Thomas, Scott

2000-01-01

.... A computer model was developed using a finite difference solution which finds the mean velocity, Poiseuille number, and volumetric flow rate in terms of the groove geometry, meniscus contact angle...

The construction of a radiometric calibration facility at Lanseria Airport, Republic of South Africa

International Nuclear Information System (INIS)

Corner, B.; Smit, C.J.B.

1982-10-01

The construction of standard sources suitable for the calibration of airborne and truck-mounted gamma-spectrometer systems is described. Four sources were built, three of which were doped with preselected quantities of uranium, thorium or potassium. A fourth source was left barren so as to provide a measure of the background radiation in the area. The sources are 8 m in diameter, 0,35 m thick and are recessed into the disused northern portion of runway 17 at Lanseria Airport, north of Johannesburg. Adopted concentrations of the major radioelements in the sources are: 6,24 % K 2 O in the potassium source, 65,0 ppm U 3 O 8 in the uranium source and 150 ppm ThO 2 in the thorium source

The construction of a radiometric calibration facility at Lanseria Airport, Republic of South Africa

International Nuclear Information System (INIS)

Corner, B.; Smit, C.J.B.

1983-08-01

The construction of standard sources suitable for the calibration of airborne and truck-mounted gamma-spectrometer systems is described. Four sources were built, three of which were doped with preselected quantities of uranium, thorium or potassium. A fourth source was left barren so as to provide a measure of the background radiation in the area. The sources are 8 m in diameter, 0,35 m thick and are recessed into the disused northern portion of runway 17 at Lanseria Airport, north of Johannesburg. Adopted concentrations of the major radioelements in the sources are: 6,10 % k 2 O in the potasssium source, 67,0 ppm U 3 O 8 in the uranium source (radiometric), 158 ppm ThO 2 in the thorium source

DETERMINING AND VERIFYING THE GEOMETRIC CHARACTERISTICS OF HELICAL GROOVES IN THE WORM IN PLANETARY TOROIDAL DRIVES IN A MORE EFFECTIVE WAY

Directory of Open Access Journals (Sweden)

Jarmila VOJTKOVÁ

2017-09-01

Full Text Available In the toroidal drive, a screw-shaped groove is cut into the globoid worm. There is contact with the rolling element in this groove. This helix can be described by parametric equations. When calculating the values of the first and second curvature of the curve, as well as the radius of curvature, we must calculate the individual derivations. A new, more effective way is to determine the values already mentioned by using NX software only. When using Siemens PLM NX software, it is not necessary to determine individual derivations and their values, although the NX software determines the radii of the first and second curvature, based on the defined helix curve.

Protein Recognition in Drug-Induced DNA Alkylation: When the Moonlight Protein GAPDH Meets S23906-1/DNA Minor Groove Adducts.

Science.gov (United States)

Savreux-Lenglet, Gaëlle; Depauw, Sabine; David-Cordonnier, Marie-Hélène

2015-11-05

DNA alkylating drugs have been used in clinics for more than seventy years. The diversity of their mechanism of action (major/minor groove; mono-/bis-alkylation; intra-/inter-strand crosslinks; DNA stabilization/destabilization, etc.) has undoubtedly major consequences on the cellular response to treatment. The aim of this review is to highlight the variety of established protein recognition of DNA adducts to then particularly focus on glyceraldehyde-3-phosphate dehydrogenase (GAPDH) function in DNA adduct interaction with illustration using original experiments performed with S23906-1/DNA adduct. The introduction of this review is a state of the art of protein/DNA adducts recognition, depending on the major or minor groove orientation of the DNA bonding as well as on the molecular consequences in terms of double-stranded DNA maintenance. It reviews the implication of proteins from both DNA repair, transcription, replication and chromatin maintenance in selective DNA adduct recognition. The main section of the manuscript is focusing on the implication of the moonlighting protein GAPDH in DNA adduct recognition with the model of the peculiar DNA minor groove alkylating and destabilizing drug S23906-1. The mechanism of action of S23906-1 alkylating drug and the large variety of GAPDH cellular functions are presented prior to focus on GAPDH direct binding to S23906-1 adducts.

[The possibility of provision of hygienically safe residing for the population in residential construction located closely to air transport enterprises].

Science.gov (United States)

Gildenskiold, R S; Tatyanyuk, T K; Savelyev, S I; Rekis, V K

Operation of the modern heavy aircraft on the surrounding vast territory is associated with the appearance of high levels of sound pressure generated by the powerful engines, especially during takeoff and landing operations. Currently, the elimination or significant reduction of noise pollution on the environment technically does not yet have a radical solution and the possible reduction of the impact ofnoise pollution on the residents ofnearby settlements is achievedfor residents of building by the optimal location of the runway, changing in conditions for the takeoff and landing of aircrafts, the ordering of the regimen of the airport, the introduction of the package sufficiently effective anti-noise diverse - engineering, planning activities, in some cases, the creation ofprotective noise shield on the border of the residential area and the construction ofprotective awnings over the children’s and sports fields with fencing shields converted in the direction of the runway. An example of a positive decision, taking into account the complexity and variety of aspects of the problem, it is possible to consider the development of the project plan of the new microdistrict «Eletsky» in the Soviet district of the city of Lipetsk, falling under the impact of aircraft noise of plying aircrafts of the military airfield.

Outcomes After Conservative, Endoscopic, and Surgical Treatment of Groove Pancreatitis: A Systematic Review.

Science.gov (United States)

Kager, Liesbeth M; Lekkerkerker, Selma J; Arvanitakis, Marianna; Delhaye, Myriam; Fockens, Paul; Boermeester, Marja A; van Hooft, Jeanin E; Besselink, Marc G

2017-09-01

Groove pancreatitis (GP) is a focal form of chronic pancreatitis affecting the paraduodenal groove area, for which consensus on diagnosis and management is lacking. We performed a systematic review of the literature to determine patient characteristics and imaging features of GP and to evaluate clinical outcomes after treatment. Eight studies were included reporting on 335 GP patients with a median age of 47 years (range, 34 to 64 y), with 90% male, 87% smokers, and 87% alcohol consumption, and 47 months (range, 15 to 122 mo) of follow-up. Most patients presented with abdominal pain (91%) and/or weight loss (78%). Imaging frequently showed cystic lesions (91%) and duodenal stenosis (60%).Final treatment was conservative (eg, pain medication) in 29% of patients. Endoscopic treatment (eg, pseudocyst drainage) was applied in 19% of patients-34% of these patients were subsequently referred for surgery. Overall, 59% of patients were treated surgically (eg, pancreatoduodenectomy). Complete symptom relief was observed in 50% of patients who were treated conservatively, 57% who underwent endoscopic treatment, and 79% who underwent surgery. GP is associated with male gender, smoking, and alcohol consumption. The vast majority of patients presents with abdominal pain and with cystic lesions on imaging. Although surgical treatment seems to be the most effective, both conservative and endoscopic treatment are successful in about half of patients. A stepwise treatment algorithm starting with the least invasive treatment options seems advisable.

Highly efficient absorption of visible and near infrared light in convex gold and nickel grooves

DEFF Research Database (Denmark)

Eriksen, René Lynge; Beermann, Jonas; Søndergaard, Thomas

The realization of nonresonant light absorption with nanostructured metal surfaces by making practical use of nanofocusing optical energy in tapered plasmonic waveguides, is of one of the most fascinating and fundamental phenomena in plasmonics [1,2]. We recently realized broadband light absorption...... in gold via adiabatic nanofocusing of gap surface plasmon modes in well-defined geometries of ultra-sharp convex grooves and being excited by scattering off subwavelength-sized wedges [3]....

Origin of DNA-Induced Circular Dichroism in a Minor-Groove Binder.

Science.gov (United States)

Holmgaard List, Nanna; Knoops, Jérémie; Rubio-Magnieto, Jenifer; Idé, Julien; Beljonne, David; Norman, Patrick; Surin, Mathieu; Linares, Mathieu

2017-10-25

Induced circular dichroism (ICD) of DNA-binding ligands is well known to be strongly influenced by the specific mode of binding, but the relative importance of the possible mechanisms has remained undetermined. With a combination of molecular dynamics simulations, CD response calculations, and experiments on an AT-sequence, we show that the ICD of minor-groove-bound 4',6-diamidino-2-phenylindole (DAPI) originates from an intricate interplay between the chiral imprint of DNA, off-resonant excitonic coupling to nucleobases, charge-transfer, and resonant excitonic coupling between DAPIs. The significant contributions from charge-transfer and the chiral imprint to the ICD demonstrate the inadequacy of a standard Frenkel exciton theory of the DAPI-DNA interactions.

Use of Data Comm by Flight Crew to Conduct Interval Management Operations to Parallel Dependent Runways

Science.gov (United States)

Baxley, Brian T.; Hubbs, Clay; Shay, Rick; Karanian, James

2011-01-01

The Interval Management (IM) concept is being developed as a method to maintain or increase high traffic density airport arrival throughput while allowing aircraft to conduct near idle thrust descents. The Interval Management with Spacing to Parallel Dependent Runways (IMSPiDR1) experiment at NASA Langley Research Center used 24 commercial pilots to examine IM procedures to conduct parallel dependent runway arrival operations while maintaining safe but efficient intervals behind the preceding aircraft. The use of IM procedures during these operations requires a lengthy and complex clearance from Air Traffic Control (ATC) to the participating aircraft, thereby making the use of Controller Pilot Data Link Communications (CPDLC) highly desirable as the communication method. The use of CPDLC reduces the need for voice transmissions between controllers and flight crew, and enables automated transfer of IM clearance elements into flight management systems or other aircraft avionics. The result is reduced crew workload and an increase in the efficiency of crew procedures. This paper focuses on the subset of data collected related to the use of CPDLC for IM operations into a busy airport. Overall, the experiment and results were very successful, with the mean time under 43 seconds for the flight crew to load the clearance into the IM spacing tool, review the calculated speed, and respond to ATC. An overall mean rating of Moderately Agree was given when the crews were asked if the use of CPDLC was operationally acceptable as simulated in this experiment. Approximately half of the flight crew reported the use of CPDLC below 10,000 for IM operations was unacceptable, with 83% reporting below 5000 was unacceptable. Also described are proposed modifications to the IM operations that may reduce CPDLC Respond time to less than 30 seconds and should significantly reduce the complexity of crew procedures, as well as follow-on research issues for operational use of CPDLC during IM

An optimum design on rollers containing the groove with changeable inner diameter based on response surface methodology

Directory of Open Access Journals (Sweden)

Xi Zhao

2016-05-01

Full Text Available In order to realize the precision plastic forming of the revolving body component with changeable wall thickness, a kind of roller containing grooves with changeable inner diameter is put forward, as the forming mould of the technology of rolling-extrusion. Specifically, first, the arc length of the groove in the roller is designed according to the prediction on the forward slip value during the process of forming, to make accurate control of the actual length of the forming segments; then, to obtain better parameters of the roller structure, a second-order response surface model combining finite element numerical simulation and response surface methodology was put forward, taking the factor of forming uniformity as evaluation index. The result of the experiment shows that, for the formed component, not only the size can meet the needs but also each mechanical property index can be greatly improved, which verify the rationality of the forward slip model and the structural parameter of the optimum model based on the response surface methodology.

Short-cavity DBR laser using an InP/InGaAsP deep-ridge waveguide with vertical-groove gratings

NARCIS (Netherlands)

Segawa, T.; Docter, B.; Kakitsuka, T.; Matsuo, S.; Ishii, T.; Kawaguchi, Y.; Kondo, Y.; Karouta, F.; Smit, M.K.; Suzuki, H.

2007-01-01

A compact distributed Bragg reflector (DBR) laser was fabricated using an InP/InGaAsP deep-ridge waveguide with vertical-groove gratings. We achieved stable single-mode laser operation with an active length of only 25-µm with low threshold current.

[The supportive outcome of periodontal non-surgical therapy to severe chronic periodontitis accompanied with malformed lingual groove in lateral incisor for 6 years: a case report].

Science.gov (United States)

Li, Zheng; Kang, Jun

2011-06-01

To track the initiating and developing process of one case diagnosed as chronic periodontitis accompanied with malformed lingual groove in maxillary lateral incisor and report the long-term prognosis to the periodontal conservative and supportive therapy. The patient was diagnosed with mild chronic periodontitis 6 years ago and accepted routine periodontal scaling and root planning (SRP) plus supportive periodontal therapy (SPT) one time. Two years later the periodontal condition deteriorated by deep pockets in molars and severe bone destruction around the maxillary lateral incisor with malformed lingual groove. After SRP in sites which pocket depth more than 4mm plus root canal therapy and lingual groove plasty of maxillary right lateral incisor, the SPT regularly proceeded at 3rd, 6th and 12th month. At present the whole periodontal tissue was healthy, the bone lesion around maxillary lateral incisor recovered well, the tooth had no mobile, the cosmetic effect andtooth function was in good state, and the patient was very satisfied.

In-situ inspection of grooves in reactor tube sheet using a remotely operated cast impression taking device

International Nuclear Information System (INIS)

Rajendran, S.; Ramakumar, M.S.

1996-01-01

Utmost importance is given to the in-service inspection of critical components of a reactor to ensure its reliable performance during the reactor operation. This paper describes a cast taking device using cold setting resin to take impression of the grooves being made in the tube sheet for sparger tube installation in pressurised heavy water reactor. (author)

The C-terminal helix of ribosomal P stalk recognizes a hydrophobic groove of elongation factor 2 in a novel fashion.

Science.gov (United States)

Tanzawa, Takehito; Kato, Koji; Girodat, Dylan; Ose, Toyoyuki; Kumakura, Yuki; Wieden, Hans-Joachim; Uchiumi, Toshio; Tanaka, Isao; Yao, Min

2018-04-06

Archaea and eukaryotes have ribosomal P stalks composed of anchor protein P0 and aP1 homodimers (archaea) or P1•P2 heterodimers (eukaryotes). These P stalks recruit translational GTPases to the GTPase-associated center in ribosomes to provide energy during translation. The C-terminus of the P stalk is known to selectively recognize GTPases. Here we investigated the interaction between the P stalk and elongation factor 2 by determining the structures of Pyrococcus horikoshii EF-2 (PhoEF-2) in the Apo-form, GDP-form, GMPPCP-form (GTP-form), and GMPPCP-form bound with 11 C-terminal residues of P1 (P1C11). Helical structured P1C11 binds to a hydrophobic groove between domain G and subdomain G' of PhoEF-2, where is completely different from that of aEF-1α in terms of both position and sequence, implying that such interaction characteristic may be requested by how GTPases perform their functions on the ribosome. Combining PhoEF-2 P1-binding assays with a structural comparison of current PhoEF-2 structures and molecular dynamics model of a P1C11-bound GDP form, the conformational changes of the P1C11-binding groove in each form suggest that in response to the translation process, the groove has three states: closed, open, and release for recruiting and releasing GTPases.

STANDARD METHODS FOR THE DETERMINATION OF THE RUNWAY AND SEAKEEPING CHARACTERISTICS OF A SEAPLANE ON THE WATERS DURING FULL-SCALE TESTS

Directory of Open Access Journals (Sweden)

A. A. Khokhlov

2015-01-01

Full Text Available One of the main stages of the creation of seaplanes and amphibious aircraft are flight certification tests, including tests to determine their landing and sailing characteristics on the water. In accordance with aviation regulations (part 21 certification work is carried out according to the methods of determination of compliance (MOC, which are the main organizational and methodological document for testing. The paper discusses the main provisions of the standard methods for the determination of the runway and sea keeping characteristics of seaplanes and amphibians on water areas with full-scale tests.

Traction suture modification to tongue-in-groove caudal septoplasty.

Science.gov (United States)

Indeyeva, Y A; Lee, T S; Gordin, E; Chan, D; Ducic, Y

2018-02-01

Caudal septal deviation leads to unfavorable esthetic as well as functional effects on the nasal airway. A modification to the tongue-in-groove (TIG) technique to correct these caudal septal deformities is described. With placement of a temporary suspension suture to the caudal septum, manual traction is applied, assuring that the caudal septum remains in the midline position while it is being secured with multiple through-and-through, trans-columellar and trans-septal sutures. From 2003 to 2016, 148 patients underwent endonasal septoplasty using this modified technique, with excellent functional and cosmetic outcomes and a revision rate of 1.4%. This modified TIG technique replaces the periosteal suture that secures the caudal septum to the midline nasal crest in the original TIG technique. This simplifies the procedure and minimizes the risk of securing the caudal septum off-midline when used in endonasal septoplasty. Copyright © 2017 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Construction concepts and validation of the 3D printed UST_2 modular stellarator

Science.gov (United States)

Queral, V.

2015-03-01

High accuracy, geometric complexity and thus high cost of stellarators tend to hinder the advance of stellarator research. Nowadays, new manufacturing methods might be developed for the production of small and middle-size stellarators. The methods should demonstrate advantages with respect common fabrication methods, like casting, cutting, forging and welding, for the construction of advanced highly convoluted modular stellarators. UST2 is a small modular three period quasi-isodynamic stellarator of major radius 0.26 m and plasma volume 10 litres being currently built to validate additive manufacturing (3D printing) for stellarator construction. The modular coils are wound in grooves defined on six 3D printed half period frames designed as light truss structures filled by a strong filler. A geometrically simple assembling configuration has been concocted for UST2 so as to try to lower the cost of the device while keeping the positioning accuracy of the different elements. The paper summarizes the construction and assembling concepts developed, the devised positioning methodology, the design of the coil frames and positioning elements and, an initial validation of the assembling of the components.

Direction of Intercalation of a bis-Ru(II) Complex to DNA Probed by a Minor Groove Binding Molecule 4',6-Diamidino-2-phenylindole

Energy Technology Data Exchange (ETDEWEB)

Jang, Yoon Jung; Kim, Raeyeong; Chitrapriya, Nataraj; Kim, Seog K.; Bae, Inho [Yeungnam Univ., Gyeongsan (Korea, Republic of)

2013-10-15

Direction of intercalation to DNA of the planar dipyrido[3,2-a:2',3'-c]phenazine ligands (dppz) of a bis-Ru(II) complex namely, [Ru(1,10-phenanthroline){sub 2}dipyrido[3,2-a:2',3'-c]phenazine]{sup 2+} linkered by a 1,3-bis(4-pyridyl)propane, was investigated by probing the behavior of 4',6-diamidino-2-phenylindole (DAPI) that bound deep in the minor groove. Bis-intercalation of DPPZ resulted in a little blue shift and hyperchromism in DAPI absorption band, and a large decrease in DAPI fluorescence intensity which accompanied by an increase in the dppz emission intensity. Diminishing the intensity of the positive induced circular dichroism (CD) and linear dichroism (LD) were also observed. These spectral changes indicated that insertion of dppz ligand caused the change of the binding mode of DAPI, which probably moved to the exterior of DNA from the minor groove and interacted with the phospghate groups of DNA by electrostatic interaction. At the surface of DNA, DAPI binds at the phosphate groups of DNA by electrostatic attraction. Consequently, this observation indicated that the dppz ligand intercalated from the minor groove.

Design, fabrication, and dynamic testing of a V-groove radiator mechanical development unit

Science.gov (United States)

Petrick, S. Walter; Bard, Steven

1988-01-01

This paper describes the design, fabrication, and dynamic testing of a V-groove radiator development unit. The intended goal was to survive the dynamic environment of the Mars Observer mission. The development unit was designed to achieve a temperature of 80 K with a heat load of about 80 milliwatts. An analysis was performed to predict the thermal performance of the development unit. The radiator with a mass mockup of a Gamma Ray Spectrometer detector, the most massive of the candidate Mars Observer instrument detectors (1.7 Kg), passed vibration and acoustic testing to the Mars Observer requirements in effect at that time.

Modelling, design and analysis of liquid crystal waveguides in preferentially etched silicon grooves

International Nuclear Information System (INIS)

Bellini, Bob; Beccherelli, Romeo

2009-01-01

This paper presents a fully consistent theoretical framework for liquid crystal (LC) channel waveguides that have been experimentally demonstrated in previous publications. We revise the optical design of the LC waveguides in silicon grooves and implement here a vectorial, fully consistent model of the LC waveguide electro-optical behaviour, based on the finite element method. The numerical investigation shows that LC waveguides demonstrate properties of propagation control and switching. They switch on and off with a low applied voltage. We discuss the major design parameters of the device and the effect of loss-inducing control electrodes.

Behavior of solvent-exposed hydrophobic groove in the anti-apoptotic Bcl-XL protein: clues for its ability to bind diverse BH3 ligands from MD simulations.

Directory of Open Access Journals (Sweden)

Dilraj Lama

Full Text Available Bcl-XL is a member of Bcl-2 family of proteins involved in the regulation of intrinsic pathway of apoptosis. Its overexpression in many human cancers makes it an important target for anti-cancer drugs. Bcl-XL interacts with the BH3 domain of several pro-apoptotic Bcl-2 partners. This helical bundle protein has a pronounced hydrophobic groove which acts as a binding region for the BH3 domains. Eight independent molecular dynamics simulations of the apo/holo forms of Bcl-XL were carried out to investigate the behavior of solvent-exposed hydrophobic groove. The simulations used either a twin-range cut-off or particle mesh Ewald (PME scheme to treat long-range interactions. Destabilization of the BH3 domain-containing helix H2 was observed in all four twin-range cut-off simulations. Most of the other major helices remained stable. The unwinding of H2 can be related to the ability of Bcl-XL to bind diverse BH3 ligands. The loss of helical character can also be linked to the formation of homo- or hetero-dimers in Bcl-2 proteins. Several experimental studies have suggested that exposure of BH3 domain is a crucial event before they form dimers. Thus unwinding of H2 seems to be functionally very important. The four PME simulations, however, revealed a stable helix H2. It is possible that the H2 unfolding might occur in PME simulations at longer time scales. Hydrophobic residues in the hydrophobic groove are involved in stable interactions among themselves. The solvent accessible surface areas of bulky hydrophobic residues in the groove are significantly buried by the loop LB connecting the helix H2 and subsequent helix. These observations help to understand how the hydrophobic patch in Bcl-XL remains stable in the solvent-exposed state. We suggest that both the destabilization of helix H2 and the conformational heterogeneity of loop LB are important factors for binding of diverse ligands in the hydrophobic groove of Bcl-XL.

Groove Pancreatitis, a Masquerading Yet Distinct Clinicopathological Entity: Analysis of Risk Factors and Differentiation.

Science.gov (United States)

Oza, Veeral M; Skeans, Jacob M; Muscarella, Peter; Walker, Jon P; Sklaw, Brett C; Cronley, Kevin M; El-Dika, Samer; Swanson, Benjamin; Hinton, Alice; Conwell, Darwin L; Krishna, Somashekar G

2015-08-01

Our objective was to delineate predictive factors differentiating groove pancreatitis (GP) from other lesions involving the head of the pancreas (HOP). A case-control study of patients older than 10 years was performed comparing patients with GP to those with other surgically resected HOP lesions. Thirteen patients with GP (mean ± SD age, 51.9 ± 10.5 years; 11 males [84.6%]), all with a history of smoking (mean, 37.54 ± 17.8 pack-years), were identified. Twelve patients (92.3%) had a history of heavy alcohol drinking (heavy alcohol [EtOH]). The mean lesion size was 2.6 ± 1.1 cm, and the CA 19-9 was elevated (>37 IU/mL) in 5 patients (45.5%). The most common histopathologic condition was duodenal wall cyst with myofibroblastic proliferation and changes of chronic pancreatitis in the HOP.Univariate analysis revealed decreasing age, male sex, weight loss, nausea/vomiting, heavy EtOH, smoking, and a history of chronic pancreatitis were predictive of GP. A multivariate analysis among smokers demonstrated that weight loss (P = 0.006; odds ratio, 11.96; 95% confidence interval, 2.1-70.2), and heavy EtOH (P pancreatic adenocarcinoma (n = 183), weight loss and heavy EtOH remained predictive of GP. Groove pancreatitis in the HOP is associated with a history of heavy EtOH and weight loss. In the absence of these symptoms, it is essential to rule out a malignant lesion.

Development of Preemptive Repair Technology for Alloy 600 J-Groove Welds of Reactor Vessel Upper Head CEDM Nozzles

Energy Technology Data Exchange (ETDEWEB)

Jung, Kwang Woon; Lee, Jang Wook; Cho, Ki Hyun; Choi, Kwang Min; Choi, Dong Chul; Cho, Sang Beum; Cho, Hong Seok [KEPCO, Daejeon (Korea, Republic of)

2016-05-15

After 2000, PWSCC in numerous NPPs around the world has been generated, and recently, PWSCC in several CEDM nozzles of domestic NPP Hanbit Unit 3 and 4 was founded and repaired with embedded flaw repair(EFR) welding method by Westinghouse. In this study, development status of EFR equipment and basic experimental results for preventive PWSCC of RVUH CEDM nozzles will be introduced. The development of EFR seal welding equipment and welding process for the preemptive repair with original Alloy 600 J-Groove welds of RVUHP was conducted. The EFR welding equipment was tested to be possible seal welding to track J-Groove welds with three dimensional curved surfaces and OD penetration with vertical welding position. Through several BOP and overlay welding experiments, it was verified that good weld beads with no defects, such as cracks, spatter, undercut at the stable welding conditions with heat input of 27.4-32.5 KJ/in were well produced. Consequently, it is expected that the EFR seal welding technique will be applicable on the site.

O-band electrically injected quantum dot micro-ring lasers on on-axis (001) GaP/Si and V-groove Si.

Science.gov (United States)

Wan, Yating; Jung, Daehwan; Norman, Justin; Shang, Chen; MacFarlane, Ian; Li, Qiang; Kennedy, M J; Gossard, Arthur C; Lau, Kei May; Bowers, John E

2017-10-30

We report statistical comparisons of lasing characteristics in InAs quantum dot (QD) micro-rings directly grown on on-axis (001) GaP/Si and V-groove (001) Si substrates. CW thresholds as low as 3 mA and high temperature operation exceeding 80 °C were simultaneously achieved on the GaP/Si template template with an outer-ring radius of 50 µm and a ring width of 4 μm, while a sub-milliamp threshold of 0.6 mA was demonstrated on the V-groove Si template with a smaller cavity size of 5-μm outer-ring radius and 3-μm ring width. Evaluations were also made with devices fabricated simultaneously on native GaAs substrates over a significant sampling analysis. The overall assessment spotlights compelling insights in exploring the optimum epitaxial scheme for low-threshold lasing on industry standard Si substrates.

Are the osseous and tendinous-cartilaginous tibial tuberosity-trochlear groove distances the same on CT and MRI?

International Nuclear Information System (INIS)

Bremer Hinckel, Betina; Gomes Gobbi, Riccardo; Pecora, Jose Ricardo; Camanho, Gilberto Luis; Demange, Marco Kawamura; Noda Kihara Filho, Eduardo; Bordalo Rodrigues, Marcelo

2015-01-01

To verify whether the tibial tuberosity-trochlear groove distance (TT-TG) and the tendinous-cartilaginous TT-TG (the distance between the patellar tendon and trochlear groove: PT-TG) are identical using computed tomography (CT) and magnetic resonance imaging (MRI) techniques. The TT-TG and PT-TG distances were measured on the same knee samples by three observers (two measurements per observer) using CT and MRI scans collected retrospectively. The reproducibility of the measurements was assessed using the interclass correlation coefficient (ICC). The means and standard deviations of four measurements were calculated for each patient. A paired t-test was used to assess differences between measurements. Fifty knee samples (32 with patellar instability and 18 with other conditions) were evaluated. The inter- and intraobserver reliability was excellent for all four measurements (>0.8). On average, the TT-TG distance on MRI was 3.1-3.6 mm smaller than that on CT, and the PT-TG distance on MRI was 1.0-3.4 mm larger than the TT-TG distance on MRI. The osseous TT-TG and tendinous-cartilaginous PT-TG distances determined by CT and MRI were not identical. (orig.)

Are the osseous and tendinous-cartilaginous tibial tuberosity-trochlear groove distances the same on CT and MRI?

Energy Technology Data Exchange (ETDEWEB)

Bremer Hinckel, Betina; Gomes Gobbi, Riccardo; Pecora, Jose Ricardo; Camanho, Gilberto Luis; Demange, Marco Kawamura [Institute of Orthopaedics and Traumatology of the Clinical Hospital of the Medical School of the University of Sao Paulo, Department of Orthopaedics, Sao Paulo (Brazil); Noda Kihara Filho, Eduardo; Bordalo Rodrigues, Marcelo [Institute of Orthopaedics and Traumatology of the Clinical Hospital of the Medical School of the University of Sao Paulo, Department of Musculoskeletal Radiology, Sao Paulo (Brazil)

2015-08-15

To verify whether the tibial tuberosity-trochlear groove distance (TT-TG) and the tendinous-cartilaginous TT-TG (the distance between the patellar tendon and trochlear groove: PT-TG) are identical using computed tomography (CT) and magnetic resonance imaging (MRI) techniques. The TT-TG and PT-TG distances were measured on the same knee samples by three observers (two measurements per observer) using CT and MRI scans collected retrospectively. The reproducibility of the measurements was assessed using the interclass correlation coefficient (ICC). The means and standard deviations of four measurements were calculated for each patient. A paired t-test was used to assess differences between measurements. Fifty knee samples (32 with patellar instability and 18 with other conditions) were evaluated. The inter- and intraobserver reliability was excellent for all four measurements (>0.8). On average, the TT-TG distance on MRI was 3.1-3.6 mm smaller than that on CT, and the PT-TG distance on MRI was 1.0-3.4 mm larger than the TT-TG distance on MRI. The osseous TT-TG and tendinous-cartilaginous PT-TG distances determined by CT and MRI were not identical. (orig.)

Surgical management with intentional replantation on a tooth with palato-radicular groove

Directory of Open Access Journals (Sweden)

Jorge Forero-López

2015-05-01

Full Text Available A palato-radicular groove (PRG is a developmental anomaly primarily found in the maxillary lateral incisors. It is a potential communication path between the root canal and the periodontium that decreases the survival prognosis of the affected tooth, therefore compromising the stability of the dental structure in the oral cavity. The aim of this case report is to present an original technique where a PRG was treated by means of intracanal disinfection, PRG sealing with glass ionomer, replantation with intentional horizontal 180 degree rotation of the tooth, and an aesthetic veneer placed to provide adequate tooth morphology. The clinical and biological benefits of this novel technique are presented and discussed.

Alleviation of spike stall in axial compressors utilizing grooved casing treatment

Directory of Open Access Journals (Sweden)

Reza Taghavi-Zenouz

2015-06-01

Full Text Available This article deals with application of grooved type casing treatment for suppression of spike stall in an isolated axial compressor rotor blade row. The continuous grooved casing treatment covering the whole compressor circumference is of 1.8 mm in depth and located between 90% and 108% chord of the blade tip as measured from leading edge. The method of investigation is based on time-accurate three-dimensional full annulus numerical simulations for cases with and without casing treatment. Discretization of the Navier–Stokes equations has been carried out based on an upwind second-order scheme and k-ω-SST (Shear Stress Transport turbulence modeling has been used for estimation of eddy viscosity. Time-dependent flow structure results for the smooth casing reveal that there are two criteria for spike stall inception known as leading edge spillage and trailing edge backflow, which occur at specific mass flow rates in near-stall conditions. In this case, two dominant stall cells of different sizes could be observed. The larger one is caused by the spike stall covering roughly two blade passages in the circumferential direction and about 25% span in the radial direction. Spike stall disturbances are accompanied by lower frequencies and higher amplitudes of the pressure signals. Casing treatment causes flow blockages to reduce due to alleviation of backflow regions, which in turn reduces the total pressure loss and increases the axial velocity in the blade tip gap region, as well as tip leakage flow fluctuation at higher frequencies and lower amplitudes. Eventually, it can be concluded that the casing treatment of the stepped tip gap type could increase the stall margin of the compressor. This fact is basically due to retarding the movement of the interface region between incoming and tip leakage flows towards the rotor leading edge plane and suppressing the reversed flow around the blade trailing edge.

The role of the sliding direction against a grooved channel texture on tool steel: An experimental study on tactile friction

NARCIS (Netherlands)

Zhang, S.; Rodriguez Urribarri, A.; Morales Hurtado, M.; Zeng, X.; Heide, E. van der

2015-01-01

To control tactile friction, that is the friction between fingertip and counter-body, the role of surface texture is required to be unveiled and defined. In this research, an experimental approach is used based on measuring tactile friction for directional texture (grooved channel) with varying

Imidazopyridine/Pyrrole and hydroxybenzimidazole/pyrrole pairs for DNA minor groove recognition.

Science.gov (United States)

Renneberg, Dorte; Dervan, Peter B

2003-05-14

The DNA binding properties of fused heterocycles imidazo[4,5-b]pyridine (Ip) and hydroxybenzimidazole (Hz) paired with pyrrole (Py) in eight-ring hairpin polyamides are reported. The recognition profile of Ip/Py and Hz/Py pairs were compared to the five-membered ring pairs Im/Py and Hp/Py on a DNA restriction fragment at four 6-base pair recognition sites which vary at a single position 5'-TGTNTA-3', where N = G, C, T, A. The Ip/Py pair distinguishes G.C from C.G, T.A, and A.T, and the Hz/Py pair distinguishes T.A from A.T, G.C, and C.G, affording a new set of heterocycle pairs to target the four Watson-Crick base pairs in the minor groove of DNA.

Methylene blue binding to DNA with alternating AT base sequence: minor groove binding is favored over intercalation.

Science.gov (United States)

Rohs, Remo; Sklenar, Heinz

2004-04-01

The results presented in this paper on methylene blue (MB) binding to DNA with AT alternating base sequence complement the data obtained in two former modeling studies of MB binding to GC alternating DNA. In the light of the large amount of experimental data for both systems, this theoretical study is focused on a detailed energetic analysis and comparison in order to understand their different behavior. Since experimental high-resolution structures of the complexes are not available, the analysis is based on energy minimized structural models of the complexes in different binding modes. For both sequences, four different intercalation structures and two models for MB binding in the minor and major groove have been proposed. Solvent electrostatic effects were included in the energetic analysis by using electrostatic continuum theory, and the dependence of MB binding on salt concentration was investigated by solving the non-linear Poisson-Boltzmann equation. We find that the relative stability of the different complexes is similar for the two sequences, in agreement with the interpretation of spectroscopic data. Subtle differences, however, are seen in energy decompositions and can be attributed to the change from symmetric 5'-YpR-3' intercalation to minor groove binding with increasing salt concentration, which is experimentally observed for the AT sequence at lower salt concentration than for the GC sequence. According to our results, this difference is due to the significantly lower non-electrostatic energy for the minor groove complex with AT alternating DNA, whereas the slightly lower binding energy to this sequence is caused by a higher deformation energy of DNA. The energetic data are in agreement with the conclusions derived from different spectroscopic studies and can also be structurally interpreted on the basis of the modeled complexes. The simple static modeling technique and the neglect of entropy terms and of non-electrostatic solute

The effect of retentive groove, sandblasting and cement type on the retentive strength of stainless steel crowns in primary second molars--an in vitro comparative study.

Science.gov (United States)

Veerabadhran, M M; Reddy, V; Nayak, U A; Rao, A P; Sundaram, M A

2012-01-01

This in vitro study was conducted to find out the effect of retentive groove, sand blasting and cement type on the retentive strength of stainless steel crowns in primary second molars. Thirty-two extracted intact human maxillary and mandibular primary second molars were embedded in aluminum blocks utilizing autopolymerising acrylic resin. After tooth preparation, the 3M stainless steel crown was adjusted to the prepared tooth. Then weldable buccal tubes were welded on the buccal and lingual surfaces of each crown as an attachment for the testing machine. A full factorial design matrix for four factors (retentive groove placement on the tooth, cement type, sandblasting and primary second molar) at two levels each was developed and the study was conducted as dictated by the matrix. The lower and upper limits for each factor were without and with retentive groove placement on the tooth, GIC and RMGIC, without and with sandblasting of crown, maxillary and mandibular second primary molar. For those teeth for which the design matrix dictated groove placement, the retentive groove was placed on the middle third of the buccal surface of the tooth horizontally and for those crowns for which sandblasting of the crowns are to be done, sandblasting was done with aluminium oxide with a particle size of 250 mm. The crowns were luted with either GIC or RMGIC, as dictated by the design matrix. Then the retentive strength of each sample was evaluated by means of an universal testing machine. The obtained data was analyzed using ANOVA for statistical analysis of the data and 't'- tests for pairwise comparison. The mean retentive strength in kg/cm 2 stainless steel crowns luted with RMGIC was 19.361 and the mean retentive strength of stainless steel crowns luted with GIC was 15.964 kg/cm 2 with a mean difference of 3.397 kg/cm 2 and was statistically significant. The mean retentive strength in kg/cm 2 of stainless steel crowns, which was not sandblasted, was 18.880 and which was

GaAs Solar Cells on V-Grooved Silicon via Selective Area Growth: Preprint

Energy Technology Data Exchange (ETDEWEB)

Warren, Emily L [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Jain, Nikhil [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Tamboli, Adele C [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Vaisman, Michelle [Yale University; Li, Qiang [Hong Kong University of Science and Technology; Lau, Kei May [Hong Kong University of Science and Technology

2017-08-31

Interest in integrating III-Vs onto Si has recently resurged as a promising pathway towards high-efficiency, low-cost tandem photovoltaics. Here, we present a single junction GaAs solar cell grown monolithically on polished Si (001) substrates using V-grooves, selective area growth, and aspect ratio trapping to mitigate defect formation without the use of expensive, thick graded buffers. The GaAs is free of antiphase domains and maintains a relatively low TDD of 4x107 cm-2, despite the lack of a graded buffer. This 6.25 percent-efficient demonstration solar cell shows promise for further improvements to III-V/Si tandems to enable cost-competitive photovoltaics.

Plasmonic black metals via radiation absorption by two-dimensional arrays of ultra-sharp convex grooves

DEFF Research Database (Denmark)

Beermann, Jonas; Eriksen, René L.; Stær, Tobias Holmgaard

2014-01-01

Plasmonic black surfaces formed by two-dimensional arrays of ultra-sharp convex metal grooves, in which the incident radiation is converted into gap surface plasmon polaritons (GSPPs) and subsequently absorbed (via adiabatic nanofocusing), are fabricated and investigated experimentally for gold......%, averaged over the investigated wavelength range of 400-985 nm. The highest averaged absorption level (similar to 97%) is achieved with 250-nm-period arrays in palladium that also has the highest melting temperature(similar to 15526 degrees C), promising thereby potential applications for broadband...

The morphology of synovial grooves (Fossae synoviales) in joints of cattle of different age groups

DEFF Research Database (Denmark)

Wegener, K. M.; Heje, N. I.; Aarestrup, Frank Møller

1993-01-01

The joint cartilage of the head of the radius, the metacarpal bone, the tibial cochlea, the proximal trochlea of the talus and the metatarsal bone of 26 cattle in the age groups fetuses, 0 days, 2-5 weeks, 2-5 months, 7-13 months, 2-3.5 years, and 5-7 years were examined macroscopically...... animals aged from 3 weeks to 13 months dyschondroplastic (osteochondrotic) lesions were observed in the joint cartilage both inside and outside the groove areas on one or more joint surfaces....

The Aerodynamic Performance of an Over-the-Rotor Liner With Circumferential Grooves on a High Bypass Ratio Turbofan Rotor

Science.gov (United States)

Bozak, Richard F.; Hughes, Christopher E.; Buckley, James

2013-01-01

While liners have been utilized throughout turbofan ducts to attenuate fan noise, additional attenuation is obtainable by placing an acoustic liner over-the-rotor. Previous experiments have shown significant fan performance losses when acoustic liners are installed over-the-rotor. The fan blades induce an oscillating flow in the acoustic liners which results in a performance loss near the blade tip. An over-the-rotor liner was designed with circumferential grooves between the fan blade tips and the acoustic liner to reduce the oscillating flow in the acoustic liner. An experiment was conducted in the W-8 Single-Stage Axial Compressor Facility at NASA Glenn Research Center on a 1.5 pressure ratio fan to evaluate the impact of this over-the-rotor treatment design on fan aerodynamic performance. The addition of a circumferentially grooved over-the-rotor design between the fan blades and the acoustic liner reduced the performance loss, in terms of fan adiabatic efficiency, to less than 1 percent which is within the repeatability of this experiment.

Study on the tongue and groove effect of the elekta multileaf collimator using Monte Carlo simulation and film dosimetry

Energy Technology Data Exchange (ETDEWEB)

Haryanto, F.; Fippel, M.; Bakai, A.; Nuesslin, F. [Dept. of Medical Physics, Radiooncologic Univ. Clinic, Tuebingen (Germany)

2004-01-01

Background: nowadays, multileaf collimation of the treatment fields from medical linear accelerators is a common option. Due to the design of the leaf sides, the tongue and groove effect occurs for certain multileaf collimator applications such as the abutment of fields where the beam edges are defined by the sides of the leaves. Material and methods: in this study, the tongue and groove effect was measured for two pairs of irregular multileaf collimator fields that were matched along leaf sides in two steps. Measurements were made at 10 cm depth in a polystyrene phantom using Kodak EDR2 films for a photon beam energy of 6 MV on an elekta sli-plus accelerator. To verify the measurements, full Monte Carlo simulations were done. In the simulations, the design of the leaf sides was taken into account and one component module of BEAM code was modified to correctly simulate the elekta multileaf collimator. Results and conclusion: the results of measurements and simulations are in good agreement and within the tolerance of film dosimetry. (orig.)

Nordic numerical round robin for a side-grooved ct-specimen

International Nuclear Information System (INIS)

Talja, H.

1989-11-01

The reliability of fracture mechanics assessments based on finite element method calculations has to be confirmed before making safety assessments for critical components like nuclear pressure vessels. Calculations for simulation of fracture mechanics tests and numerical round robin programmes are useful methods in such verification. In this report the results of Nordic finite element round robin calculations for a side-grooved CT-specimen are presented and compared with experimental results. The round robin consisted of two parts. In the first part two-dimensional calculations assuming plane strain and plane stress behaviour were made. In the second part extensive three-dimensional calculations were performed for best-estimate analysis of the specimen behaviour. The differences between the solutions were comparatively small. Only one two-dimensional solution, where lower order finite elements were used, deviated clearly from the other ones. A good agreement was seen between two-dimensional plane strain results and experimental results. Three-dimensional calculations corresponded very accurately with each others and the experiment

Evaporation thermal anslysis of Swallow-tailed Axial-grooved Heat Pipe

Science.gov (United States)

Zhang, Renping

2018-03-01

A detailed mathematical model that describes evaporating characteristics through thin liquid film at the evaporator section of swallow-tailed axial-grooved heat pipe was developed. The numerical simulation results about thin film profile, liquid-vapour interface temperature, evaporating rate and heat flux at the evaporating thin film region were given by the current investigation and the effect of superheat on the liquid-vapour interface temperature, evaporating mass rate and heat flux was discussed. Meanwhile, thermal model of the meniscus region at the evaporating section was developed to calculate the rate of heat transfer. The ratio of the heat conduction in the evaporating thin liquid film region and total heat rate were also discussed. It is indicated that the thickness of thin liquid film rises in a nearly linear fashion. The disjoining pressure can be neglected with increasing the liquid film thickness, tends to be negligibly small. The heat transfer rate at the intrinsic meniscus cannot be compared with that of the evaporating liquid film region.

Construction concepts and validation of the 3D printed UST-2 modular stellarator

International Nuclear Information System (INIS)

Queral, V

2015-01-01

High accuracy, geometric complexity and thus high cost of stellarators tend to hinder the advance of stellarator research. Nowadays, new manufacturing methods might be developed for the production of small and middle-size stellarators. The methods should demonstrate advantages with respect common fabrication methods, like casting, cutting, forging and welding, for the construction of advanced highly convoluted modular stellarators. UST-2 is a small modular three period quasi-isodynamic stellarator of major radius 0.26 m and plasma volume 10 litres being currently built to validate additive manufacturing (3D printing) for stellarator construction. The modular coils are wound in grooves defined on six 3D printed half period frames designed as light truss structures filled by a strong filler. A geometrically simple assembling configuration has been concocted for UST-2 so as to try to lower the cost of the device while keeping the positioning accuracy of the different elements. The paper summarizes the construction and assembling concepts developed, the devised positioning methodology, the design of the coil frames and positioning elements and, an initial validation of the assembling of the components. (paper)

HCV IRES domain IIb affects the configuration of coding RNA in the 40S subunit's decoding groove.

Science.gov (United States)

Filbin, Megan E; Kieft, Jeffrey S

2011-07-01

Hepatitis C virus (HCV) uses a structured internal ribosome entry site (IRES) RNA to recruit the translation machinery to the viral RNA and begin protein synthesis without the ribosomal scanning process required for canonical translation initiation. Different IRES structural domains are used in this process, which begins with direct binding of the 40S ribosomal subunit to the IRES RNA and involves specific manipulation of the translational machinery. We have found that upon initial 40S subunit binding, the stem-loop domain of the IRES that contains the start codon unwinds and adopts a stable configuration within the subunit's decoding groove. This configuration depends on the sequence and structure of a different stem-loop domain (domain IIb) located far from the start codon in sequence, but spatially proximal in the IRES•40S complex. Mutation of domain IIb results in misconfiguration of the HCV RNA in the decoding groove that includes changes in the placement of the AUG start codon, and a substantial decrease in the ability of the IRES to initiate translation. Our results show that two distal regions of the IRES are structurally communicating at the initial step of 40S subunit binding and suggest that this is an important step in driving protein synthesis.

Swift heavy ion irradiation of CaF2 - from grooves to hillocks in a single ion track

Science.gov (United States)

Gruber, Elisabeth; Salou, Pierre; Bergen, Lorenz; El Kharrazi, Mourad; Lattouf, Elie; Grygiel, Clara; Wang, Yuyu; Benyagoub, Abdenacer; Levavasseur, Delphine; Rangama, Jimmy; Lebius, Henning; Ban-d'Etat, Brigitte; Schleberger, Marika; Aumayr, Friedrich

2016-10-01

A novel form of ion-tracks, namely nanogrooves and hillocks, are observed on CaF2 after irradiation with xenon and lead ions of about 100 MeV kinetic energy. The irradiation is performed under grazing incidence (0.3°-3°) which forces the track to a region in close vicinity to the surface. Atomic force microscopy imaging of the impact sites with high spatial resolution reveals that the surface track consists in fact of three distinct parts: each swift heavy ion impacting on the CaF2 surface first opens a several 100 nm long groove bordered by a series of nanohillocks on both sides. The end of the groove is marked by a huge single hillock and the further penetration of the swift projectile into deeper layers of the target is accompanied by a single protrusion of several 100 nm in length slowly fading until the track vanishes. By comparing experimental data for various impact angles with results of a simulation, based on a three-dimensional version of the two-temperature-model (TTM), we are able to link the crater and hillock formation to sublimation and melting processes of CaF2 due to the local energy deposition by swift heavy ions.

The Use of Fiberglass and Ceramic Cylinders to Support the Root Pass in C-Steel Welds with a Double-V Groove

Directory of Open Access Journals (Sweden)

Ricardo Fernandes Gurgel

2015-09-01

Full Text Available Abstract The aim of this work is to evaluate the effectiveness of fiberglass and ceramic fiber cylinders as root-pass weld backing for a double-V groove in 16 mm-thick carbon steel. Three different cylinder diameters were tested: 4.8, 9.5 mm (fiberglass and 6.4 mm (ceramic fiber. The welding process used was GMAW. The welding technique and the following process variables were investigated: root opening, current and travel speed. The results show that cylindrical fiberglass and ceramic fiber backings not only have excellent refractory properties, but also seal the root opening and contain the weld pool sufficiently to produce a root bead free of discontinuities and with a satisfactory shape and geometry. Working points were defined, together with a possible operating range for the welding parameters. It was concluded that cylindrical fiberglass and ceramic fiber weld backings hold great promise for use in root-pass welds in double-V grooves in applications in the naval and metallurgical industry.

Detailed study of grooved heat pipes for a system functioning study; Etude fine des caloducs rainures en vue d`une etude systeme

Energy Technology Data Exchange (ETDEWEB)

Alexandre, A [Ecole Nationale Superieure de Mecanique et d` Aerotechnique (ENSMA), 86 - Poitiers (France)

1997-12-31

The functioning of a heat pipe is complex. In this paper, a methodology for a detailed analysis of the functioning of a grooved heat pipe is developed in order to obtain the information required for a general analysis of such systems. (J.S.) 3 refs.

Detailed study of grooved heat pipes for a system functioning study; Etude fine des caloducs rainures en vue d`une etude systeme

Energy Technology Data Exchange (ETDEWEB)

Alexandre, A. [Ecole Nationale Superieure de Mecanique et d`Aerotechnique (ENSMA), 86 - Poitiers (France)

1996-12-31

The functioning of a heat pipe is complex. In this paper, a methodology for a detailed analysis of the functioning of a grooved heat pipe is developed in order to obtain the information required for a general analysis of such systems. (J.S.) 3 refs.

Elucidation of the sequence selective binding mode of the DNA minor groove binder adozelesin, by high-field 1H NMR and restrained molecular dynamics

International Nuclear Information System (INIS)

Cameron, L.

1999-01-01

Adozelesin (formerly U73-975, The Upjohn Co.) is a covalent, minor-groove binding analogue of the antitumour antibiotic (+)CC-1065. Adozelesin consists of a cyclopropapyrroloindole alkylating sub-unit identical to (+)CC-1065, plus indole and benzofuran sub-units which replace the more complex pyrroloindole B and C sub-units, respectively, of (+)CC-1065. Adozelesin is a clinically important drug candidate, since it does not contain the ethylene bridge moieties on the B and C sub-units which are thought to be responsible for the unusual delayed hepatotoxicity exhibited by (+)CC-1065. Sequencing techniques identified two consensus sequences for adozelesin binding as p(dA) and 5'(T/A)(T/A)T-A*(C/G)G. This suggests that adozelesin spans a total of five base-pairs and shows a preference for A=T base-pair rich sequences, thus avoiding steric crowding around the exocyclic NH 2 of guanine and a wide minor groove. In this project, the covalent modification of two DNA sequences, i.e. 5'd(CGTAAGCGCTTA*CG) 2 and 5'-d(CGAAAAA*CGG)· 5'-d(CCGTTTTTCG), by adozelesin was examined by high-field NMR and restrained molecular mechanics and dynamics. Previous studies of minor groove binding drugs, using techniques as diverse as NMR, X-ray crystallography and molecular modelling, indicate that the incorporation of a guanine into the consensus sequence sterically hinders binding and, more importantly, produces a wider minor groove which is a 'slack' fit for the ligand. The aim of this investigation was to provide an insight into the sequence selective binding of adozelesin to 5'-AAAAA*CG and 5'-GCTTA*CG. The 1 H NMR data revealed that, in both cases, β-helical structure and Watson-Crick base-pairing was maintained on adduct formation. The 5'-GCTTA*CG adduct displayed significant distortion of the guanine base on the non-covalently modified strand. This distortion resulted from an amalgamation of two factors. Firstly, the presence of a strong hydrogen-bond between the amide linker of the

From Runway to Orbit: Reflections of a NASA Engineer

Science.gov (United States)

Iliff, Kenneth W.; Peebles, Curtis L.

2004-01-01

In his remarkable memoir Runway to Orbit, Dr. Kenneth W. Iliff - the recently retired Chief Scientist of the NASA Dryden Flight Research Center- tells a highly personal, yet a highly persuasive account of the last forty years of American aeronautical research. His interpretation of events commands respect, because over these years he has played pivotal roles in many of the most important American aeronautics and spaceflight endeavors. Moreover, his narrative covers much of the second half of the first 100 years of flight, a centennial anniversary being celebrated this year. aerospace knowledge. He arrived at the then NASA Flight Research Center in 1962 as a young aeronautical engineer and quickly became involved in two of the seminal projects of modern flight, the X-15 and the lifting bodies. In the process, he pioneered (with Lawrence Taylor) the application of digital computing to the reduction of flight data, arriving at a method known as parameter estimation, now applied the world over. Parameter estimation not only enabled researchers to acquire stability and control derivatives from limited flight data, but in time allowed them to obtain a wide range of aerodynamic effects. Although subsequently involved in dozens of important projects, Dr. Iliff devoted much of his time and energy to hypersonic flight, embodied in the Shuttle orbiter (or as he refers to it, the world s fastest airplane). To him, each Shuttle flight, instrumented to obtain a variety of data, represents a research treasure trove, one that he has mined for years. This book, then, represents the story of Dr. Ken Iliff s passion for flight, his work, and his long and astoundingly productive career. It can be read with profit not just by scientists and engineers, but equally by policy makers, historians, and journalists wishing to better comprehend advancements in flight during the second half of the twentieth century. Dr. Iliff's story is one of immense contributions to the nation s repository of

Suppression of inducer stall based on inlet recirculation in a centrifugal impeller. 1st Report. Improvement in stall limit by ring groove arrangement; Enshin haneguruma iriguchi junkanryu ni yoru inducer shissoku no yokusei. 1. kanjoko ni yoru shissoku genkai no kaizen

Energy Technology Data Exchange (ETDEWEB)

Ueki, H.; Ishida, M.; Sakaguchi, D.; Sun, Z. [Nagasaki University, Nagasaki (Japan). Faculty of Engineering

2000-07-25

A ring groove arrangement is proposed to suppress unstable flow or surge in a centrifugal blower. The ring groove arrangement connects the upstream position of impeller inlet and the inducer throat tip through a bypass. The recirculation flow 'vas formed by the pressure difference between the two positions, and the recirculation flow rate was changed by increasing the ring groove widths. The inlet recirculation results in a decrease in the flow rate of unstable flow inception, and an up to 800 improvement in stall limit was obtained by the ring groove arrangement at a small expense of the delivery pressure drop. The improvement of stall limit in the present experiment seems to be mainly due to decrease in flow incidence based on the inlet recirculation flow. Tre flow incidence decreases more as the recirculation flow rate increases, thus resulting in a larger improvement in stall limit. (author)

The use of tibial tuberosity-trochlear groove indices based on joint size in lower limb evaluation.

Science.gov (United States)

Ferlic, Peter Wilhelm; Runer, Armin; Dirisamer, Florian; Balcarek, Peter; Giesinger, Johannes; Biedermann, Rainer; Liebensteiner, Michael Christian

2018-05-01

The correlation between tibial tuberosity-trochlear groove distance (TT-TG) and joint size, taking into account several different parameters of knee joint size as well as lower limb dimensions, is evaluated in order to assess whether TT-TG indices should be used in instead of absolute TT-TG values. This study comprised a retrospective analysis of knee CT scans, including 36 cases with patellofemoral instability (PFI) and 30 controls. Besides TT-TG, five measures of knee joint size were evaluated in axial CT slices: medio-lateral femur width, antero-posterior lateral condylar height, medio-lateral width of the tibia, width of the patella and the proximal-distal joint size (TT-TE). Furthermore, the length of the femur, the tibia and the total leg length were measured in the CT scanogram. Correlation analysis of TT-TG and the other parameters was done by calculating the Spearman correlation coefficient. In the PFI group lateral condylar height (r = 0.370), tibia width (r = 0.406) and patella width (r = 0.366) showed significant moderate correlations (p joint size or between TT-TG and measures of lower limb length. Tibial tuberosity-trochlear groove distance correlates with several parameters of knee joint size and leg length in patients with patellofemoral instability. Application of indices determining TT-TG as a ratio of joint size could be helpful in establishing the indication for medial transfer of the tibial tuberosity in patients with PFI. Level III.

Ultrastructure of the harmful unarmored dinoflagellate Cochlodinium polykrikoides (Dinophyceae) with reference to the apical groove and Flagellar apparatus.

Science.gov (United States)

Iwataki, Mitsunori; Hansen, Gert; Moestrup, Øjvind; Matsuoka, Kazumi

2010-01-01

The external and internal ultrastructure of the harmful unarmored dinoflagellate Cochlodinium polykrikoides Margalef has been examined with special reference to the apical groove and three-dimensional structure of the flagellar apparatus. The apical groove is U-shaped and connected to the anterior sulcal extension on the dorsal side of the epicone. The eyespot is located dorsally and composed of two layers of globules situated within the chloroplast. A narrow invagination of the plasma membrane is associated with the eyespot. The nuclear envelope has normal nuclear pores similar to other eukaryotes but different from the Gymnodinium group with diagnostic nuclear chambers. The longitudinal and transverse basal bodies are separated by approximately 0.5-1.0 microm and interconnected directly by a striated basal body connective and indirectly by microtubular and fibrous structures. Characteristic features of the flagellar apparatus are as follows: (1) a nuclear extension projects to the R1 (longitudinal microtubular root) and is connected to the root by thin fibrous material; (2) fibrillar structures are associated with the longitudinal and transverse flagellar canal; and (3) a striated ventral connective extends toward the posterior end of the cell along the longitudinal flagellar canal. We conclude, based on both morphological and molecular evidence, that Cochlodinium is only distantly related to Gymnodinium.

Effects of Gas Rarefaction on Dynamic Characteristics of Micro Spiral-Grooved Thrust Bearing.

Science.gov (United States)

Liu, Ren; Wang, Xiao-Li; Zhang, Xiao-Qing

2012-04-01

The effects of gas-rarefaction on dynamic characteristics of micro spiral-grooved-thrust-bearing are studied. The Reynolds equation is modified by the first order slip model, and the corresponding perturbation equations are then obtained on the basis of the linear small perturbation method. In the converted spiral-curve-coordinates system, the finite-volume-method (FVM) is employed to discrete the surface domain of micro bearing. The results show, compared with the continuum-flow model, that under the slip-flow regime, the decrease in the pressure and stiffness become obvious with the increasing of the compressibility number. Moreover, with the decrease of the relative gas-film-thickness, the deviations of dynamic coefficients between slip-flow-model and continuum-flow-model are increasing.

Place of the brachytherapy in the therapeutic strategy of rhabdomyosarcomas of the nasogenian groove of children

International Nuclear Information System (INIS)

Breton-Callu, C.; Haie-Meder, C.; Oberlin, O.; Delapierre, M.; Gerbaulet, A.

2000-01-01

The brachytherapy in the treatment of rhabdomyosarcomas of the nasogenian groove has to be discussed when it exists a residual tumor after an initial chemotherapy and leads to good results, in term of local control. An advantage of the brachytherapy in comparison with external irradiation, in the treatment of children tumors, is the small size of the treated volume, that allows to decrease the aftereffects incidence. The brachytherapy comes in the frame of a therapeutic needing a multidisciplinary approach and a cooperation between surgeons, brachy-therapists and onco-pediatricians. (N.C.)

Settlement duration and materiality: formal chronological models for the development of Barnhouse, a Grooved Ware settlement in Orkney

OpenAIRE

Richards, Colin; Jones, Andrew Meirion; MacSween, Ann; Sheridan, Alison; Dunbar, Elaine; Reimer, Paula; Bayliss, Alex; Griffiths, Seren; Whittle, Alasdair

2016-01-01

Radiocarbon dating and Bayesian chronological modelling, undertaken as part of the investigation by the Times of Their Lives project into the development of Late Neolithic settlement and pottery in Orkney, has provided precise new dating for the Grooved Ware settlement of Barnhouse, excavated in 1985–91. Previous understandings of the site and its pottery are presented. A Bayesian model based on 70 measurements on 62 samples (of which 50 samples are thought to date accurately the deposits fro...

Engineering Manual for McMurdo Station. Revision

Science.gov (United States)

1979-01-01

runway vided greater security from ice breakout but .’ >, surface and unseen cracks in the surrounding was not suitable for construction of runways...an approximately 600-foot-long and 170-foot-wtde area of sea ice was thickened to a maximum of 29 feet. This wharf was secured to the shore by cables...water distribution netowrk . 8. Waste energy from the power plant should be used as a heat source for utilidor heating. 9. Alternate techniques of

Selenide isotope generator for the Galileo Mission. Axially-grooved heat pipe: accelerated life test results

International Nuclear Information System (INIS)

1979-08-01

The results through SIG/Galileo contract close-out of accelerated life testing performed from June 1978 to June 1979 on axially-grooved, copper/water heat pipes are presented. The primary objective of the test was to determine the expected lifetime of axially-grooved copper/water heat pipes. The heat pipe failure rate, due to either a leak or a build-up of non-condensible gas, was determined. The secondary objective of the test was to determine the effects of time and temperature on the thermal performance parameters relevant to long-term (> 50,000 h) operation on a space power generator. The results showed that the gas generation rate appears to be constant with time after an initial sharp rise although there are indications that it drops to approximately zero beyond approx. 2000 h. During the life test, the following pipe-hours were accumulated: 159,000 at 125 0 C, 54,000 at 165 0 C, 48,000 at 185 0 C, and 8500 at 225 0 C. Heated hours per pipe ranged from 1000 to 7500 with an average of 4720. Applying calculated acceleration factors yields the equivalent of 930,000 pipe-h at 125 0 C. Including the accelerated hours on vendor tested pipes raises this number to 1,430,000 pipe-hours at 125 0 C. It was concluded that, for a heat pipe temperature of 125 0 C and a mission time of 50,000 h, the demonstrated heat pipe reliability is between 80% (based on 159,000 actual pipe-h at 125 0 C) and 98% (based on 1,430,000 accelerated pipe-h at 125 0 C). Measurements indicate some degradation of heat transfer with time, but no detectable degradation of heat transport

A rotordynamic analysis of circumferentially-grooved pump seals based on a three-control-volume theory

International Nuclear Information System (INIS)

Ha, Tae Woong; Lee, An Sung

2000-01-01

In this paper the leakage prediction and rotordynamic analysis of an annular seal with a smooth rotor and circumferentially grooved stator are performed based on a three-control-volume theory. The present analysis is validated by comparing with the experimental data of Iwatsubo and Sheng and theoretical results suggested by Marquette and Childs. For the leakage prediction the present analysis shows a good agreement with Marquette and Childs' result and a qualitation agreement with Iwatsubo and Shengs' experimental data. Direct and cross-coupled stiffness coefficients show closer agreement with the experimental values than those of Marquette and Childs. However, direct damping coefficient shows greater discrepancy from the experimental value than Marquette and Childs'

Usability Evaluation of Spot and Runway Departure Advisor (SARDA) Concept in Dallas/Fort Worth Airport Tower Simulation

Science.gov (United States)

Hayashi, Miwa; Hoang, Ty; Jung, Yoon C.; Gupta, Gautam; Malik, Waqar; Dulchinos, Victoria

2013-01-01

Spot and Runway Departure Advisor (SARDA) is a proposed decision-support tool for air traffic control tower controllers for reducing taxi delay and optimizing the departure sequence. In the present study, the tool's usability was evaluated to ensure that its claimed performance benefits are not being realized at the cost of increasing the work burden on controllers. For the evaluation, workload ratings and questionnaire responses collected during a human-in-the-loop simulation experiment were analyzed to assess the SARDA advisories' effects on the controllers' ratings on cognitive resources (e.g., workload, spare attention) and satisfaction. The results showed that SARDA reduced the controllers' workload and increased their spare attention. It also made workload and attention levels less susceptible to the effects of increases in the traffic load. The questionnaire responses suggested that the controllers generally were satisfied with the ease of use of the tool and the objectives of the SARDA concept, but with some caution. To gain more trust from controllers, the the reasoning behind advisories may need to be made more transparent to them.

Effects of hydrogen irradiation on the optical and electronic properties of site-controlled InGaAsN V-groove quantum wires

International Nuclear Information System (INIS)

Felici, M.; Pettinari, G.; Polimeni, A.; Lavenuta, G.; Tartaglini, E.; De Luca, M.; Capizzi, M.; Carron, R.; Gallo, P.; Dwir, B.; Rudra, A.; Kapon, E.; Notargiacomo, A.; Fekete, D.; Christianen, P. C. M.; Maan, J. C.

2013-01-01

The properties of InGaAsN V-groove quantum wires (QWRs) –both untreated and irradiated with atomic hydrogen– are probed via micro-magneto-photoluminescence (PL) and polarization-dependent PL. As generally observed in dilute-nitride materials, H irradiation is found to fully passivate nitrogen, thus allowing us to accurately assess –and to precisely control– the effects of N incorporation in the QWRs

Using mutagenesis to explore conserved residues in the RNA-binding groove of influenza A virus nucleoprotein for antiviral drug development

Science.gov (United States)

Liu, Chia-Lin; Hung, Hui-Chen; Lo, Shou-Chen; Chiang, Ching-Hui; Chen, I.-Jung; Hsu, John T.-A.; Hou, Ming-Hon

2016-02-01

Nucleoprotein (NP) is the most abundant type of RNA-binding viral protein in influenza A virus-infected cells and is necessary for viral RNA transcription and replication. Recent studies demonstrated that influenza NP is a valid target for antiviral drug development. The surface of the groove, covered with numerous conserved residues between the head and body domains of influenza A NP, plays a crucial role in RNA binding. To explore the mechanism by which NP binds RNA, we performed a series of site-directed mutagenesis in the RNA-binding groove, followed by surface plasmon resonance (SPR), to characterize the interactions between RNA and NP. Furthermore, a role of Y148 in NP stability and NP-RNA binding was evaluated. The aromatic residue of Y148 was found to stack with a nucleotide base. By interrupting the stacking interaction between Y148 and an RNA base, we identified an influenza virus NP inhibitor, (E, E)-1,7-bis(4-hydroxy-3-methoxyphenyl) -1,6-heptadiene-3,5-dione; this inhibitor reduced the NP’s RNA-binding affinity and hindered viral replication. Our findings will be useful for the development of new drugs that disrupt the interaction between RNA and viral NP in the influenza virus.

Comparison of positions of the trochlear groove line and the vertical midline of the pericondylar rectangle on axial computed tomography: a retrospective pilot study

International Nuclear Information System (INIS)

Nizic, Dinko

2012-01-01

To compare the positions of the trochlear groove (TG) line and the vertical midline of the pericondylar rectangle on axial computed tomography (CT). A retrospective pilot study was conducted in February and March 2011 comprising 14 knees in 9 consecutive patients with patellofemoral pain, a normal trochlear angle (124 -145 ), and no medical record of prior knee surgery. After the axial CT image displaying the center of the trochlear groove (''reference cut'') with a normal trochlear angle was identified, the pericondylar rectangle was drawn and located in the first quadrant of the Cartesian rectangular coordinate system. The x-coordinates of the vertical lines passing through the most posterior point of the trochlear groove (TG line) and the midpoints of the horizontal sides of the pericondylar rectangle (vertical midline) were obtained at 2-week intervals and statistically analyzed as matched pairs for differences (Wilcoxon signed rank test), agreements (Bland-Altman plot, intraclass correlation coefficient [ICC]) and relative variations (coefficient of variation [CV]). There were no statistically significant differences between matched pairs (2-tailed p from 0.583 to 0.641) whereas the agreements were substantial (bias = -0.37 and -0.45 respectively, ICC = 0.688 and 0.670 respectively) to almost perfect for duplicate measurements (bias = 0.11 and 0.04 respectively, ICC = 0.975 and 0.998 respectively), with much less relative variation with regard to the vertical midline (CV = 1.22% to CV = 0.34% respectively). The positions of the TG line and the vertical midline of the pericondylar rectangle on axial CT were identical. The latter was identified regardless of trochlear morphology. (orig.)

Comparison of positions of the trochlear groove line and the vertical midline of the pericondylar rectangle on axial computed tomography: a retrospective pilot study

Energy Technology Data Exchange (ETDEWEB)

Nizic, Dinko [Zagreb University Hospital Center, Clinical Institute of Diagnostic and Interventional Radiology, Zagreb (Croatia)

2012-09-15

To compare the positions of the trochlear groove (TG) line and the vertical midline of the pericondylar rectangle on axial computed tomography (CT). A retrospective pilot study was conducted in February and March 2011 comprising 14 knees in 9 consecutive patients with patellofemoral pain, a normal trochlear angle (124 -145 ), and no medical record of prior knee surgery. After the axial CT image displaying the center of the trochlear groove (''reference cut'') with a normal trochlear angle was identified, the pericondylar rectangle was drawn and located in the first quadrant of the Cartesian rectangular coordinate system. The x-coordinates of the vertical lines passing through the most posterior point of the trochlear groove (TG line) and the midpoints of the horizontal sides of the pericondylar rectangle (vertical midline) were obtained at 2-week intervals and statistically analyzed as matched pairs for differences (Wilcoxon signed rank test), agreements (Bland-Altman plot, intraclass correlation coefficient [ICC]) and relative variations (coefficient of variation [CV]). There were no statistically significant differences between matched pairs (2-tailed p from 0.583 to 0.641) whereas the agreements were substantial (bias = -0.37 and -0.45 respectively, ICC = 0.688 and 0.670 respectively) to almost perfect for duplicate measurements (bias = 0.11 and 0.04 respectively, ICC = 0.975 and 0.998 respectively), with much less relative variation with regard to the vertical midline (CV = 1.22% to CV = 0.34% respectively). The positions of the TG line and the vertical midline of the pericondylar rectangle on axial CT were identical. The latter was identified regardless of trochlear morphology. (orig.)

Tissue-engineered cartilaginous constructs for the treatment of caprine cartilage defects, including distribution of laminin and type IV collagen.

Science.gov (United States)

Jeng, Lily; Hsu, Hu-Ping; Spector, Myron

2013-10-01

The purpose of this study was the immunohistochemical evaluation of (1) cartilage tissue-engineered constructs; and (2) the tissue filling cartilage defects in a goat model into which the constructs were implanted, particularly for the presence of the basement membrane molecules, laminin and type IV collagen. Basement membrane molecules are localized to the pericellular matrix in normal adult articular cartilage, but have not been examined in tissue-engineered constructs cultured in vitro or in tissue filling cartilage defects into which the constructs were implanted. Cartilaginous constructs were engineered in vitro using caprine chondrocyte-seeded type II collagen scaffolds. Autologous constructs were implanted into 4-mm-diameter defects created to the tidemark in the trochlear groove in the knee joints of skeletally mature goats. Eight weeks after implantation, the animals were sacrificed. Constructs underwent immunohistochemical and histomorphometric evaluation. Widespread staining for the two basement membrane molecules was observed throughout the extracellular matrix of in vitro and in vivo samples in a distribution unlike that previously reported for cartilage. At sacrifice, 70% of the defect site was filled with reparative tissue, which consisted largely of fibrous tissue and some fibrocartilage, with over 70% of the reparative tissue bonded to the adjacent host tissue. A novel finding of this study was the observation of laminin and type IV collagen in in vitro engineered cartilaginous constructs and in vivo cartilage repair samples from defects into which the constructs were implanted, as well as in normal caprine articular cartilage. Future work is needed to elucidate the role of basement membrane molecules during cartilage repair and regeneration.

InAs/GaAs quantum dots on GaAs-on-V-grooved-Si substrate with high optical quality in the 1.3 μm band

International Nuclear Information System (INIS)

Wan, Yating; Li, Qiang; Geng, Yu; Shi, Bei; Lau, Kei May

2015-01-01

We report self-assembled InAs/GaAs quantum dots (QDs) grown on a specially engineered GaAs-on-V-grooved-Si substrate by metal-organic vapor phase epitaxy. Recessed pockets formed on V-groove patterned Si (001) substrates were used to prevent most of the hetero-interfacial stacking faults from extending into the upper QD active region. 1.3 μm room temperature emission from high-density (5.6 × 10 10  cm −2 ) QDs has been obtained, with a narrow full-width-at-half-maximum of 29 meV. Optical quality of the QDs was found to be better than those grown on conventional planar offcut Si templates, as indicated by temperature-dependent photoluminescence analysis. Results suggest great potential to integrate QD lasers on a Si complementary-metal-oxide-semiconductor compatible platform using such GaAs on Si templates

assessment of assessment of bagasse ash bagasse ash bagasse

African Journals Online (AJOL)

eobe

medium plasticity CL according to Unified Soil Classification System (USCS). The specific .... construction of roads, highways, aircraft runways ... experiencing an unending problem of environmental ..... “Title 25 Health: Environmental Control.

Use of jet grouting to create a low permeability horizontal barrier below an incinerator ash landfill

International Nuclear Information System (INIS)

Furth, A.J.; Burke, G.K.; Deutsch, W.L. Jr.

1997-01-01

The City of Philadelphia's Division of Aviation (DOA) has begun construction of a new commuter runway, designated as Runway 8-26, at the Philadelphia International Airport. A portion of this runway will be constructed over a former Superfund site known as the Enterprise Avenue Landfill, which for many years was used to dispose of solid waste incinerator ash and other hazardous materials. The site was clay capped in the 1980's, but in order for the DOA to use the site, additional remediation was needed to meet US EPA final closure requirements. One component of the closure plan included installation of a low permeability horizontal barrier above a very thin (approximately 0.61 to 0.91 meters) natural clay stratum which underlies an approximately 1020 m 2 area of the landfill footprint so as to insure that a minimum 1.52 meter thick low permeability barrier exists beneath the entire 150,000 m 2 landfill. The new barrier was constructed using jet grouting techniques to achieve remote excavation and replacement of the bottom 0.91 meters of the waste mass with a low permeability grout. The grout was formulated to meet the low permeability, low elastic modulus and compressive strength requirements of the project design. This paper will discuss the advantages of using jet grouting for the work and details the development of the grout mixture, modeling of the grout zone under load, field construction techniques, performance monitoring and verification testing

The effect of different screw-rod design on the anti-rotational torque: a biomechanical comparison of three conventional screw-rod constructs.

Science.gov (United States)

Huang, Zifang; Wang, Chongwen; Fan, Hengwei; Sui, Wenyuan; Li, Xueshi; Wang, Qifei; Yang, Junlin

2017-07-28

Screw-rod constructs have been widely used to correct spinal deformities, but the effects of different screw-rod systems on anti-rotational torque have not been determined. This study aimed to analyze the biomechanical effect of different rod-screw constructs on anti-rotational torque. Three conventional spinal screw-rod systems (Legacy, RF-F-10 and USSII) were used to test the anti-rotational torque in the material test machine. ANOVA was performed to evaluate the anti-rotational capacity of different pedicle screws-rod constructs. The anti-rotational torque of Legacy group, RF-F-10 group and USSII group were 12.3 ± 1.9 Nm, 6.8 ± 0.4 Nm, and 3.9 ± 0.8 Nm, with a P value lower than 0.05. This results indicated that the Legacy screws-rod construct could provide a highest anti-rotation capacity, which is 68% and 210% greater than RF-F-10 screw-rod construct and USSII screw-rod respectively. The anti-rotational torque may be mainly affected by screw cap and groove design. Our result showed the anti-rotational torque are: Legacy system > RF-F-10 system > USSII system, suggesting that appropriate rod-screw constructs selection in surgery may be vital for anti-rotational torque improvement and preventing derotation correction loss.

Performance of gas-lubricated cruciform-mounted tilting-pad journal bearings and a damped flexibly mounted spiral-groove thrust bearing

Science.gov (United States)

Ream, L. W.

1974-01-01

A test program was conducted to determine the performance characteristics of gas-lubricated cruciform-mounted tilting-pad journal bearings and a damped spiral-groove thrust bearing designed for the Brayton cycle rotating unit (BRU). Hydrostatic, hybrid (simultaneously hydrostatic and hydrodynamic), and hydrodynamic tests were conducted in argon gas at ambient pressure and temperature ranges representative of operation to the 10.5 kWe BRU power-generating level. Performance of the gas lubricated bearings is presented including hydrostatic gas flow rates, bearing clearances, bearing temperatures, and transient performance.

A worker attaches covers for the nose pitot boom before removing the unpiloted X-40 from the runway

Science.gov (United States)

2001-01-01

A worker attaches covers for the nose pitot boom before removing the unpiloted X-40 from the runway at Edwards Air Force Base, California, following its successful free-flight on March 14, 2001. The unpiloted X-40 is a risk-reduction vehicle for the X-37, which is intended to be a reusable space vehicle. NASA's Marshall Space Flight Center in Huntsville, Ala, manages the X-37 project. At Dryden, the X-40A underwent a series of ground and air tests to reduce possible risks to the larger X-37, including drop tests from a helicopter to check guidance and navigation systems planned for use in the X-37. The X-37 is designed to demonstrate technologies in the orbital and reentry environments for next-generation reusable launch vehicles that will increase both safety and reliability, while reducing launch costs from $10,000 per pound to $1,000 per pound. The X-37, carried into orbit by the Space Shuttle, is planned to fly two orbital missions to test reusable launch vehicle technologies.

Evaluation of occlusal groove patterns of mandibular first and second molars in an Indian population: A forensic anthropological study

Directory of Open Access Journals (Sweden)

Rashmi GS Phulari

2017-01-01

Full Text Available Background: The study of dental morphological characteristics is important in anthropological research as it can provide information on the phylogenetic relationship between species, as well as variations and diversities within a population. Aims and Objectives: To determine the prevalence of six types of mandibular second molars in Gujarat state and the results can be used in both forensic anthropological researches and clinical aspects of dental sciences. Materials and Methods: This descriptive investigation was undertaken among 1000 students (13–25 years old in high schools and dental institutes of Gujarat state. The students were selected by cluster sampling method and screened for the number of cusps and groove patterns of mandibular first and second molars. Gender and religion of the students were recorded on prepared forms. Statistical Analysis: It was done with the help of STATAIC-13 software. Descriptive statistics were used to summarize the data and Pearson's Chi-square test was used to check association between variables. Throughout the discussion, level of significance was set at 5%. Results and Conclusion: The high percentage of “+-”shaped groove pattern and low percentage of primitive “y-”shaped pattern in our study shows a tremendous evolutionary trend persisting in this population. The analysis of dental morphological traits is crucial in anthropological research as it can provide data on the phylogenetic relationship between species, as well as variations and diversities within a population.

Adaptable piezoelectric hemispherical composite strips using a scalable groove technique for a self-powered muscle monitoring system.

Science.gov (United States)

Alluri, Nagamalleswara Rao; Vivekananthan, Venkateswaran; Chandrasekhar, Arunkumar; Kim, Sang-Jae

2018-01-18

Contrary to traditional planar flexible piezoelectric nanogenerators (PNGs), highly adaptable hemispherical shape-flexible piezoelectric composite strip (HS-FPCS) based PNGs are required to harness/measure non-linear surface motions. Therefore, a feasible, cost-effective and less-time consuming groove technique was developed to fabricate adaptable HS-FPCSs with multiple lengths. A single HS-CSPNG generates 130 V/0.8 μA and can also work as a self-powered muscle monitoring system (SP-MMS) to measure maximum human body part movements, i.e., spinal cord, throat, jaw, elbow, knee, foot stress, palm hand/finger force and inhale/exhale breath conditions at a time or at variable time intervals.

Design and optimization of a high-efficiency array generator in the mid-IR with binary subwavelength grooves.

Science.gov (United States)

Bloom, Guillaume; Larat, Christian; Lallier, Eric; Lee-Bouhours, Mane-Si Laure; Loiseaux, Brigitte; Huignard, Jean-Pierre

2011-02-10

We have designed a high-efficiency array generator composed of subwavelength grooves etched in a GaAs substrate for operation at 4.5 μm. The method used combines rigorous coupled wave analysis with an optimization algorithm. The optimized beam splitter has both a high efficiency (∼96%) and a good intensity uniformity (∼0.2%). The fabrication error tolerances are numerically calculated, and it is shown that this subwavelength array generator could be fabricated with current electron beam writers and inductively coupled plasma etching. Finally, we studied the effect of a simple and realistic antireflection coating on the performance of the beam splitter.

Optoelectronic enhancement of monocrystalline silicon solar cells by porous silicon-assisted mechanical grooving

Energy Technology Data Exchange (ETDEWEB)

Ben Rabha, Mohamed; Mohamed, Seifeddine Belhadj; Dimassi, Wissem; Gaidi, Mounir; Ezzaouia, Hatem; Bessais, Brahim [Laboratoire de Photovoltaique, Centre de Recherches et des Technologies de l' Energie, Technopole de Borj-Cedria, BP 95, 2050 Hammam-Lif (Tunisia)

2011-03-15

One of the most important factors influencing silicon solar cells performances is the front side reflectivity. Consequently, new methods for efficient reduction of this reflectivity are searched. This has always been done by creating a rough surface that enables incident light of being absorbed within the solar cell. Combination of texturization-porous silicon surface treatment was found to be an attractive technical solution for lowering the reflectivity of monocrystalline silicon (c-Si). The texturization of the monocrystalline silicon wafer was carried out by means of mechanical grooving. A specific etching procedure was then applied to form a thin porous silicon layer enabling to remove mechanical damages. This simple and low cost method reduces the total reflectivity from 29% to 7% in the 300 - 950 nm wavelength range and enhances the diffusion length of the minority carriers from 100 {mu}m to 790 {mu}m (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Enhancing the Performance of Distributed Feedback Dye Lasers and Plasmonic V-grooves for Lab-on-a-chip Systems

DEFF Research Database (Denmark)

Smith, Cameron

The ability to perform laboratory operations in compact systems is not only advantageous for the development of diagnostics tools and their production, but also provides unique opportunities to explore the natural world on the micro- and nanoscale. To this end, we focus on two optical schemes: 1...... to the advantages they bring to lab-on-a-chip systems.......) polymer-based distributed feedback (DFB) dye lasers, and 2) plasmonic V-grooves. Regarding the first, DFB dye lasers are well suited to serve as compact, minimal analyte volume and highly sensitive refractive index sensors, where changes occurring in an analyte result in readily measurable shifts...

Design and construction of high-frequency magnetic probe system on the HL-2A tokamak

Science.gov (United States)

Liang, S. Y.; Ji, X. Q.; Sun, T. F.; Xu, Yuan; Lu, J.; Yuan, B. S.; Ren, L. L.; Yang, Q. W.

2017-12-01

A high-frequency magnetic probe system is designed, calibrated and constructed on the HL-2A tokamak. To investigate the factors which affect the probe frequency response, the inductance and capacitance in the probe system are analyzed using an equivalent circuit. Suitable sizes and turn number of the coil, and the length of transmission cable are optimized based on the theory and detailed test in the calibration. To deal with the frequency response limitation and bake-out, the ceramic grooved technique is used and the probe is wound with a bare copper wire. A cascade filter is manufactured with a suitable bandwidth as well as a good phase consistency between channels. The system has been used in the experiment to measure high frequency (≤300 kHz) magnetohydrodynamic fluctuations, which can meet the requirement of physical analysis on HL-2A.

STATUS AND DEVELOPMENT OF RUNWAY OVERRUN PREVENTION SYSTEMS

OpenAIRE

A. V. Mozolyako; A. N. Akimov; V. V. Vorobyev

2014-01-01

This article describes the current condition of the onboard braking systems while rolling and the approach to the construction of the aircraft automatic braking system. The article analysis the main reasons for RW overrun and measures of reducing the risk.

The rem mutations in the ATP-binding groove of the Rad3/XPD helicase lead to Xeroderma pigmentosum-Cockayne syndrome-like phenotypes.

Science.gov (United States)

Herrera-Moyano, Emilia; Moriel-Carretero, María; Montelone, Beth A; Aguilera, Andrés

2014-12-01

The eukaryotic TFIIH complex is involved in Nucleotide Excision Repair and transcription initiation. We analyzed three yeast mutations of the Rad3/XPD helicase of TFIIH known as rem (recombination and mutation phenotypes). We found that, in these mutants, incomplete NER reactions lead to replication fork breaking and the subsequent engagement of the homologous recombination machinery to restore them. Nevertheless, the penetrance varies among mutants, giving rise to a phenotype gradient. Interestingly, the mutations analyzed reside at the ATP-binding groove of Rad3 and in vivo experiments reveal a gain of DNA affinity upon damage of the mutant Rad3 proteins. Since mutations at the ATP-binding groove of XPD in humans are present in the Xeroderma pigmentosum-Cockayne Syndrome (XP-CS), we recreated rem mutations in human cells, and found that these are XP-CS-like. We propose that the balance between the loss of helicase activity and the gain of DNA affinity controls the capacity of TFIIH to open DNA during NER, and its persistence at both DNA lesions and promoters. This conditions NER efficiency and transcription resumption after damage, which in human cells would explain the XP-CS phenotype, opening new perspectives to understand the molecular basis of the role of XPD in human disease.

Limitations of the endonasal endoscopic approach in treating olfactory groove meningiomas. A systematic review.

Science.gov (United States)

Shetty, Sathwik Raviraj; Ruiz-Treviño, Armando S; Omay, Sacit Bulent; Almeida, Joao Paulo; Liang, Buqing; Chen, Yu-Ning; Singh, Harminder; Schwartz, Theodore H

2017-10-01

To review current management strategies for olfactory groove meningioma (OGM)s and the recent literature comparing endoscopic endonasal (EEA) with traditional transcranial (TCA) approaches. A PubMed search of the recent literature (2011-2016) was performed to examine outcomes following EEA and TCA for OGM. The extent of resection, visual outcome, postoperative complications and recurrence rates were analyzed using percentages and proportions, the Fischer exact test and the Student's t-test using Graphpad PRISM 7.0Aa (San Diego, CA) software. There were 444 patients in the TCA group with a mean diameter of 4.61 (±1.17) cm and 101 patients in the EEA group with a mean diameter of 3.55 (± 0.58) cm (p = 0.0589). GTR was achieved in 90.9% (404/444) in the TCA group and 70.2% (71/101) in the EEA group (p OGMs.

STATUS AND DEVELOPMENT OF RUNWAY OVERRUN PREVENTION SYSTEMS

Directory of Open Access Journals (Sweden)

A. V. Mozolyako

2014-01-01

Full Text Available This article describes the current condition of the onboard braking systems while rolling and the approach to the construction of the aircraft automatic braking system. The article analysis the main reasons for RW overrun and measures of reducing the risk.

Mapping surficial geology and assessment of permafrost conditions under the Iqaluit airport, Nunavut, Canada

Science.gov (United States)

Mathon-Dufour, V.; Allard, M.; Leblanc, A.; L'Hérault, E.; Oldenborger, G. A.; Sladen, W. E.

2012-12-01

Formerly, characterization of permafrost conditions was minimal before the construction of infrastructures. It was assumed that the permafrost would forever remain a solid substrate. Before global warming, transportation infrastructures were not designed, especially in terms of materials and dimensions, to withstand without damage an increased input of heat in the soil. Iqaluit airport, the hub of the eastern Canadian Arctic, is currently affected by thawing permafrost. In fact, the runway, taxiways and apron are affected by differential settlements resulting from the presence of localized ice-rich soils. This study uses a GIS approach that makes up for the absence of appropriate characterization before the construction of the airport during WWII and in the 1950s. Mapping of surficial geology, hydrography and landforms indicative of the presence of ground ice (e.g. tundra polygons) was produced by interpreting aerial photographs dating back from the initial phases of construction (1948) and photographs taken at intervals since then, to the most recent high-resolution satellite images. Subsequent map analysis shows that the original terrain conditions prevailing before the construction of the airport have a significant impact on the current stability of the infrastructure. Data integration allowed us to summarize the main problems affecting the Iqaluit airport which are: 1) Differential settlements associated with pre-construction drainage network 2) Cracking due to thermal contraction, 3) Linear depressions associated with ice wedge degradation and 4) Sink holes. Most of the sectors affected by differential settlements and instabilities are perfectly coincident with the original streams and lakes network that has been filled to increase the size of the runway, taxiways and the apron. In addition, the runway is affected by intense frost cracking. Similarities with nearby natural terrain suggest that the network pattern of the cracks follows pre-existing ice wedges

Bypassing the rumen in dairy ewes: the reticular groove reflex vs. calcium soap of olive fatty acids.

Science.gov (United States)

García, C Dobarganes; Hernández, M Pérez; Cantalapiedra, G; Salas, J M; Merino, J A

2005-02-01

A 3 x 3 Latin Square experiment was designed to compare 2 ways of bypassing the effects of the rumen with olive oil fatty acids in 'Manchega' dairy ewes. Treatments were a control diet, CaOFA (control diet plus 45 g of olive fatty acids as calcium soap), and OO (control plus 45 g/d of olive fatty acids as olive oil emulsified in skim milk) and bottle-fed to animals trained to maintain the reticular groove reflex). No differences were found in milk, protein, and lactose yields, but fat yield and milk fat content were greater in treatments with added fat (CaOFA and OO). Content of short- and medium-chain fatty acids in milk fat was greater for control treatment than for the other 2 groups, the yield of these fatty acids being similar for all 3 diets, except that of C12:0, which was greater for the control treatment. Content and yield of C18:0 and isomers of C18:1 others than oleic acid were greater in milk from the CaOFA diet than from the other 2 diets. Oleic acid content and yield were greater in milk after OO treatment (23.9% and 16.8 g/d, respectively), intermediate after CaOFA treatment (19.2% and 13.8 g/d, respectively), and lower after control diet (10.7% and 6.52 g/d, respectively). Linoleic acid yield and content were greater in ewes fed the OO diet than in those on the other 2 diets, both of which showed similar data. All these changes indicated that the "protected" olive fatty acids (as calcium soap) were severely affected by the rumen environment and that the use of the reticular groove reflex seems to be a more effective way of bypassing the rumen in adult lactating dairy ewes.

Impact of pyrrolidine-bispyrrole DNA minor groove binding agents and chirality on global proteomic profile in Escherichia Coli.

Science.gov (United States)

Yang, Ya-Ting; Lin, Chun-Yu; Jeng, Jingyueh; Ong, Chi-Wi

2013-05-23

There is great interest in the design of small molecules that selectively target minor grooves of duplex DNA for controlling specific gene expression implicated in a disease. The design of chiral small molecules for rational drug design has attracted increasing attention due to the chirality of DNA. Yet, there is limited research on the chirality effect of minor groove binders on DNA interaction, especially at the protein expression level. This paper is an attempt to illustrate that DNA binding affinity might not provide a full picture on the biological activities. Drug interacting at the genomic level can be translated to the proteomic level. Here we have illustrated that although the chiral bispyrrole-pyrrolidine-oligoamides, PySSPy and PyRSPy, showed low binding affinity to DNA, their influence at the proteomic level is significant. More importantly, the chirality also plays a role. Two-dimensional proteomic profile to identify the differentially expressed protein in Escherichia coli DH5α (E coli DH5α) were investigated. E coli DH5α incubated with the chiral PySSPy and PyRSPy, diastereomeric at the pyrrolidine ring, showed differential expression of eighteen proteins as observed through two dimensional proteomic profiling. These eighteen proteins identified by MALDI_TOF/TOF MS include antioxidant defense, DNA protection, protein synthesis, chaperone, and stress response proteins. No statistically significant toxicity was observed at the tested drug concentrations as measured via MTT assay. The current results showed that the chiral PySSPy and PyRSPy impact on the proteomic profiling of E coli DH5α, implicating the importance of drug chirality on biological activities at the molecular level.

Experimental visualization of temperature fields and study of heat transfer enhancement in oscillatory flow in a grooved channel

Energy Technology Data Exchange (ETDEWEB)

Herman, C.; Kang, E. [Dept. of Mechanical Engineering, Johns Hopkins Univ., Baltimore, MD (United States)

2001-01-01

An experimental study was conducted of incompressible, moderate Reynolds number flow of air over heated rectangular blocks in a two-dimensional, horizontal channel. Holographic interferometry combined with high-speed cinematography was used to visualize the unsteady temperature fields in self- sustained oscillatory flow. Experiments were conducted in the laminar, transitional and turbulent flow regimes for Reynolds numbers in the range from Re = 520 to Re = 6600. Interferometric measurements were obtained in the thermally and fluiddynamically periodically fully developed flow region on the ninth heated block. Flow oscillations were first observed between Re = 1054 and Re = 1318. The period of oscillations, wavelength and propagation speed of the Tollmien-Schlichting waves in the main channel were measured at two characteristic flow velocities, Re = 1580 and Re = 2370. For these Reynolds numbers it was observed that two to three waves span one geometric periodicity length. At Re = 1580 the dominant oscillation frequency was found to be around 26 Hz and at Re = 2370 the frequency distribution formed a band around 125 Hz. Results regarding heat transfer and pressure drop are presented as a function of the Reynolds number, in terms of the block-average Nusselt number and the local Nusselt number as well as the friction factor. Measurements of the local Nusselt number together with visual observations indicate that the lateral mixing caused by flow instabilities is most pronounced along the upstream vertical wall of the heated block in the groove region, and it is accompanied by high heat transfer coefficients. At Reynolds numbers beyond the onset of oscillations the heat transfer in the grooved channel exceeds the performance of the reference geometry, the asymmetrically heated parallel plate channel. (orig.)

Effects of the Tongue-in-Groove Maneuver on Nasal Tip Rotation.

Science.gov (United States)

Antunes, Marcelo B; Quatela, Vito C

2018-03-27

Changes in nasal tip rotation is a very common maneuver performed during rhinoplasty. Among the many techniques used to achieve this goal is the tongue-in-groove (TIG). This study addresses the long-term effect of the TIG on the nasal tip rotation 1 year after rhinoplasty. The authors prospectively identified patients who were submitted to a rhinoplasty with a TIG maneuver over a period of 1 year. The angle of rotation was measured along the nostril axis angle. The data was analyzed using the t-test and a linear regression model. Seventeen patients were included. The average preoperative tip rotation was 93.95° (SD, 3.12°). Immediate postoperative tip rotation averaged 114.47° (SD, 3.79°). At the 1-year follow-up appointment, the tip rotation averaged 106.55° (SD, 3.54°). There was a significant loss of rotation at the 1-year postoperative visit (pTIG is a more dependable technique than the ones that rely on healing and contraction to obtain rotation. Our data demonstrated a significant loss of rotation during the first year. This suggests that the surgeon needs to slightly overcorrect the tip rotation to account for this loss.

Reduction of front-metallization grid shading in concentrator cells through laser micro-grooved cover glass

International Nuclear Information System (INIS)

García-Linares, Pablo; Voarino, Philippe; Besson, Pierre; Baudrit, Mathieu; Dominguez, César; Dellea, Olivier; Fugier, Pascal

2015-01-01

Concentrator solar cell front-grid metallizations are designed so that the trade-off between series resistance and shading factor (SF) is optimized for a particular irradiance. High concentrator photovoltaics (CPV) typically requires a metallic electrode pattern that covers up to 10% of the cell surface. The shading effect produced by this front electrode results in a significant reduction in short-circuit current (I SC ) and hence, in a significant efficiency loss. In this work we present a cover glass (originally meant to protect the cell surface) that is laser-grooved with a micrometric pattern that redirects the incident solar light towards interfinger regions and away from the metallic electrodes, where they would be wasted in terms of photovoltaic generation. Quantum efficiency (QE) and current (I)-voltage (V) characterization under concentration validate the proof-of-concept, showing great potential for CPV applications

Combined endodontic therapy and periapical surgery with MTA and bone graft in treating palatogingival groove.

Science.gov (United States)

Mittal, Mudit; Vashisth, Pallavi; Arora, Rachita; Dwivedi, Swati

2013-04-18

A 37-year-old male patient reported to our department with chief complaint of pain and pus discharge from the labial marginal gingiva in the maxillary right lateral incisor region since last 4 months. Clinically, the tooth was hypersensitive to percussion and palpation but failed to respond to pulp sensitivity testing. After periodontal probing, a palatal groove was observed which started at the cingulum and travelled apically and laterally, associated with a pocket depth of 8 mm. Occlusal radiograph showed circumscribed radiolucency measuring 5 mm×7 mm in diameter at the apex of the tooth. A clinical diagnosis of chronic apical abscess was established. The case was treated with a combination of mineral trioxide aggregate and bone graft. At the 6-month follow-up visit, the tooth showed progressive healing without sinus track and sulcular bleeding.

Reduction of front-metallization grid shading in concentrator cells through laser micro-grooved cover glass

Energy Technology Data Exchange (ETDEWEB)

García-Linares, Pablo, E-mail: pablo.garcia-linares@cea.fr; Voarino, Philippe; Besson, Pierre; Baudrit, Mathieu [CEA-LITEN, Laboratoire de Photovoltaïque à Concentration, INES, Le Bourget du Lac (France); Dominguez, César [CEA-LITEN, Laboratoire de Photovoltaïque à Concentration, INES, Le Bourget du Lac (France); Instituto de Energía Solar - Universidad Politécnica de Madrid, Madrid (Spain); Dellea, Olivier; Fugier, Pascal [CEA-LITEN, Laboratoire de Surfaces Nanostructurées, Grenoble (France)

2015-09-28

Concentrator solar cell front-grid metallizations are designed so that the trade-off between series resistance and shading factor (SF) is optimized for a particular irradiance. High concentrator photovoltaics (CPV) typically requires a metallic electrode pattern that covers up to 10% of the cell surface. The shading effect produced by this front electrode results in a significant reduction in short-circuit current (I{sub SC}) and hence, in a significant efficiency loss. In this work we present a cover glass (originally meant to protect the cell surface) that is laser-grooved with a micrometric pattern that redirects the incident solar light towards interfinger regions and away from the metallic electrodes, where they would be wasted in terms of photovoltaic generation. Quantum efficiency (QE) and current (I)-voltage (V) characterization under concentration validate the proof-of-concept, showing great potential for CPV applications.

Atrioventricular and Interventricular Groove and Septal Extension of Right Sinus of Valsalva Aneurysm: A Rare Cause of Complete Heart Block

International Nuclear Information System (INIS)

Khan, J.A.; Hussain, M.; Rizvi, N.H.; Fehmi, N.; Hussain, A.; Sial, J.A.

2013-01-01

A 26 years old male presented with vertigo and history of fall. The electrocardiogram revealed 2:1 second-degree heart block and later progression to complete heart block. Transthoracic echocardiography revealed aneurysm at the site of ascending aorta and computed tomographic scan showed an aneurysm of right sinsus of Valsalva extending into right atrioventricular and interventricular groove and causing complete heart block by compression on the conduction system. He also suffered from lymph node tuberculosis. This case report is unique because of rare presentation as complete heart block. (author)

Field Observations of Wave-Driven Circulation over Spur and Groove Formations near the Palmyra Atoll in the North Pacific Ocean from 2012-09-16 to 2013-09-16 (NCEI Accession 0123612)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Spur and groove (SAG) formations are found on the forereefs of many coral reefs worldwide. Modeling results have shown that SAG formations together with shoaling...

Patellar instability in Indian population: relevance of tibial tuberosity and trochlear groove distance

Directory of Open Access Journals (Sweden)

Kulkarni Sourabh

2016-01-01

Full Text Available Introduction: The tibial tuberosity to trochlear groove (TTTG distance in the western population is extensively studied through various modalities such as X-rays, computerised tomography and magnetic resonance imaging. However, to our knowledge there is very little or no literature support to indicate that TTTG distance has been studied in the Indian population. Methods: We therefore undertook a study to measure the TTTG distance in 100 MRI scans of normal Indian knees. Patients with the following co-morbidities were excluded from the study; ligamentous laxity, patellofemoral instability, mal-alignment and osteoarthritis. We measured TTTG distance on the axial MRI slices using OsiriX software. Results: The mean value for females was found to be 14.07 mm and that for male was found to be 13.34 mm. Our study indicates that the TTTG distance, using MRI scans as measurement modality, in the Indian population is significantly different when compared to the published western data. Discussion: We believe that this study can form the basis for future studies on the relationship between TTTG distance and patellar instability in Indian population.